xref: /openbmc/linux/drivers/tty/synclink_gt.c (revision ded1ffea)
1 // SPDX-License-Identifier: GPL-1.0+
2 /*
3  * Device driver for Microgate SyncLink GT serial adapters.
4  *
5  * written by Paul Fulghum for Microgate Corporation
6  * paulkf@microgate.com
7  *
8  * Microgate and SyncLink are trademarks of Microgate Corporation
9  *
10  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
11  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
12  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
13  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
14  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
15  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
16  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
17  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
18  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
19  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
20  * OF THE POSSIBILITY OF SUCH DAMAGE.
21  */
22 
23 /*
24  * DEBUG OUTPUT DEFINITIONS
25  *
26  * uncomment lines below to enable specific types of debug output
27  *
28  * DBGINFO   information - most verbose output
29  * DBGERR    serious errors
30  * DBGBH     bottom half service routine debugging
31  * DBGISR    interrupt service routine debugging
32  * DBGDATA   output receive and transmit data
33  * DBGTBUF   output transmit DMA buffers and registers
34  * DBGRBUF   output receive DMA buffers and registers
35  */
36 
37 #define DBGINFO(fmt) if (debug_level >= DEBUG_LEVEL_INFO) printk fmt
38 #define DBGERR(fmt) if (debug_level >= DEBUG_LEVEL_ERROR) printk fmt
39 #define DBGBH(fmt) if (debug_level >= DEBUG_LEVEL_BH) printk fmt
40 #define DBGISR(fmt) if (debug_level >= DEBUG_LEVEL_ISR) printk fmt
41 #define DBGDATA(info, buf, size, label) if (debug_level >= DEBUG_LEVEL_DATA) trace_block((info), (buf), (size), (label))
42 /*#define DBGTBUF(info) dump_tbufs(info)*/
43 /*#define DBGRBUF(info) dump_rbufs(info)*/
44 
45 
46 #include <linux/module.h>
47 #include <linux/errno.h>
48 #include <linux/signal.h>
49 #include <linux/sched.h>
50 #include <linux/timer.h>
51 #include <linux/interrupt.h>
52 #include <linux/pci.h>
53 #include <linux/tty.h>
54 #include <linux/tty_flip.h>
55 #include <linux/serial.h>
56 #include <linux/major.h>
57 #include <linux/string.h>
58 #include <linux/fcntl.h>
59 #include <linux/ptrace.h>
60 #include <linux/ioport.h>
61 #include <linux/mm.h>
62 #include <linux/seq_file.h>
63 #include <linux/slab.h>
64 #include <linux/netdevice.h>
65 #include <linux/vmalloc.h>
66 #include <linux/init.h>
67 #include <linux/delay.h>
68 #include <linux/ioctl.h>
69 #include <linux/termios.h>
70 #include <linux/bitops.h>
71 #include <linux/workqueue.h>
72 #include <linux/hdlc.h>
73 #include <linux/synclink.h>
74 
75 #include <asm/io.h>
76 #include <asm/irq.h>
77 #include <asm/dma.h>
78 #include <asm/types.h>
79 #include <linux/uaccess.h>
80 
81 #if defined(CONFIG_HDLC) || (defined(CONFIG_HDLC_MODULE) && defined(CONFIG_SYNCLINK_GT_MODULE))
82 #define SYNCLINK_GENERIC_HDLC 1
83 #else
84 #define SYNCLINK_GENERIC_HDLC 0
85 #endif
86 
87 /*
88  * module identification
89  */
90 static const char driver_name[] = "SyncLink GT";
91 static const char tty_dev_prefix[] = "ttySLG";
92 MODULE_LICENSE("GPL");
93 #define MAX_DEVICES 32
94 
95 static const struct pci_device_id pci_table[] = {
96 	{ PCI_VDEVICE(MICROGATE, SYNCLINK_GT_DEVICE_ID) },
97 	{ PCI_VDEVICE(MICROGATE, SYNCLINK_GT2_DEVICE_ID) },
98 	{ PCI_VDEVICE(MICROGATE, SYNCLINK_GT4_DEVICE_ID) },
99 	{ PCI_VDEVICE(MICROGATE, SYNCLINK_AC_DEVICE_ID) },
100 	{ 0 }, /* terminate list */
101 };
102 MODULE_DEVICE_TABLE(pci, pci_table);
103 
104 static int  init_one(struct pci_dev *dev,const struct pci_device_id *ent);
105 static void remove_one(struct pci_dev *dev);
106 static struct pci_driver pci_driver = {
107 	.name		= "synclink_gt",
108 	.id_table	= pci_table,
109 	.probe		= init_one,
110 	.remove		= remove_one,
111 };
112 
113 static bool pci_registered;
114 
115 /*
116  * module configuration and status
117  */
118 static struct slgt_info *slgt_device_list;
119 static int slgt_device_count;
120 
121 static int ttymajor;
122 static int debug_level;
123 static int maxframe[MAX_DEVICES];
124 
125 module_param(ttymajor, int, 0);
126 module_param(debug_level, int, 0);
127 module_param_array(maxframe, int, NULL, 0);
128 
129 MODULE_PARM_DESC(ttymajor, "TTY major device number override: 0=auto assigned");
130 MODULE_PARM_DESC(debug_level, "Debug syslog output: 0=disabled, 1 to 5=increasing detail");
131 MODULE_PARM_DESC(maxframe, "Maximum frame size used by device (4096 to 65535)");
132 
133 /*
134  * tty support and callbacks
135  */
136 static struct tty_driver *serial_driver;
137 
138 static void wait_until_sent(struct tty_struct *tty, int timeout);
139 static void flush_buffer(struct tty_struct *tty);
140 static void tx_release(struct tty_struct *tty);
141 
142 /*
143  * generic HDLC support
144  */
145 #define dev_to_port(D) (dev_to_hdlc(D)->priv)
146 
147 
148 /*
149  * device specific structures, macros and functions
150  */
151 
152 #define SLGT_MAX_PORTS 4
153 #define SLGT_REG_SIZE  256
154 
155 /*
156  * conditional wait facility
157  */
158 struct cond_wait {
159 	struct cond_wait *next;
160 	wait_queue_head_t q;
161 	wait_queue_entry_t wait;
162 	unsigned int data;
163 };
164 static void flush_cond_wait(struct cond_wait **head);
165 
166 /*
167  * DMA buffer descriptor and access macros
168  */
169 struct slgt_desc
170 {
171 	__le16 count;
172 	__le16 status;
173 	__le32 pbuf;  /* physical address of data buffer */
174 	__le32 next;  /* physical address of next descriptor */
175 
176 	/* driver book keeping */
177 	char *buf;          /* virtual  address of data buffer */
178     	unsigned int pdesc; /* physical address of this descriptor */
179 	dma_addr_t buf_dma_addr;
180 	unsigned short buf_count;
181 };
182 
183 #define set_desc_buffer(a,b) (a).pbuf = cpu_to_le32((unsigned int)(b))
184 #define set_desc_next(a,b) (a).next   = cpu_to_le32((unsigned int)(b))
185 #define set_desc_count(a,b)(a).count  = cpu_to_le16((unsigned short)(b))
186 #define set_desc_eof(a,b)  (a).status = cpu_to_le16((b) ? (le16_to_cpu((a).status) | BIT0) : (le16_to_cpu((a).status) & ~BIT0))
187 #define set_desc_status(a, b) (a).status = cpu_to_le16((unsigned short)(b))
188 #define desc_count(a)      (le16_to_cpu((a).count))
189 #define desc_status(a)     (le16_to_cpu((a).status))
190 #define desc_complete(a)   (le16_to_cpu((a).status) & BIT15)
191 #define desc_eof(a)        (le16_to_cpu((a).status) & BIT2)
192 #define desc_crc_error(a)  (le16_to_cpu((a).status) & BIT1)
193 #define desc_abort(a)      (le16_to_cpu((a).status) & BIT0)
194 #define desc_residue(a)    ((le16_to_cpu((a).status) & 0x38) >> 3)
195 
196 struct _input_signal_events {
197 	int ri_up;
198 	int ri_down;
199 	int dsr_up;
200 	int dsr_down;
201 	int dcd_up;
202 	int dcd_down;
203 	int cts_up;
204 	int cts_down;
205 };
206 
207 /*
208  * device instance data structure
209  */
210 struct slgt_info {
211 	void *if_ptr;		/* General purpose pointer (used by SPPP) */
212 	struct tty_port port;
213 
214 	struct slgt_info *next_device;	/* device list link */
215 
216 	char device_name[25];
217 	struct pci_dev *pdev;
218 
219 	int port_count;  /* count of ports on adapter */
220 	int adapter_num; /* adapter instance number */
221 	int port_num;    /* port instance number */
222 
223 	/* array of pointers to port contexts on this adapter */
224 	struct slgt_info *port_array[SLGT_MAX_PORTS];
225 
226 	int			line;		/* tty line instance number */
227 
228 	struct mgsl_icount	icount;
229 
230 	int			timeout;
231 	int			x_char;		/* xon/xoff character */
232 	unsigned int		read_status_mask;
233 	unsigned int 		ignore_status_mask;
234 
235 	wait_queue_head_t	status_event_wait_q;
236 	wait_queue_head_t	event_wait_q;
237 	struct timer_list	tx_timer;
238 	struct timer_list	rx_timer;
239 
240 	unsigned int            gpio_present;
241 	struct cond_wait        *gpio_wait_q;
242 
243 	spinlock_t lock;	/* spinlock for synchronizing with ISR */
244 
245 	struct work_struct task;
246 	u32 pending_bh;
247 	bool bh_requested;
248 	bool bh_running;
249 
250 	int isr_overflow;
251 	bool irq_requested;	/* true if IRQ requested */
252 	bool irq_occurred;	/* for diagnostics use */
253 
254 	/* device configuration */
255 
256 	unsigned int bus_type;
257 	unsigned int irq_level;
258 	unsigned long irq_flags;
259 
260 	unsigned char __iomem * reg_addr;  /* memory mapped registers address */
261 	u32 phys_reg_addr;
262 	bool reg_addr_requested;
263 
264 	MGSL_PARAMS params;       /* communications parameters */
265 	u32 idle_mode;
266 	u32 max_frame_size;       /* as set by device config */
267 
268 	unsigned int rbuf_fill_level;
269 	unsigned int rx_pio;
270 	unsigned int if_mode;
271 	unsigned int base_clock;
272 	unsigned int xsync;
273 	unsigned int xctrl;
274 
275 	/* device status */
276 
277 	bool rx_enabled;
278 	bool rx_restart;
279 
280 	bool tx_enabled;
281 	bool tx_active;
282 
283 	unsigned char signals;    /* serial signal states */
284 	int init_error;  /* initialization error */
285 
286 	unsigned char *tx_buf;
287 	int tx_count;
288 
289 	bool drop_rts_on_tx_done;
290 	struct	_input_signal_events	input_signal_events;
291 
292 	int dcd_chkcount;	/* check counts to prevent */
293 	int cts_chkcount;	/* too many IRQs if a signal */
294 	int dsr_chkcount;	/* is floating */
295 	int ri_chkcount;
296 
297 	char *bufs;		/* virtual address of DMA buffer lists */
298 	dma_addr_t bufs_dma_addr; /* physical address of buffer descriptors */
299 
300 	unsigned int rbuf_count;
301 	struct slgt_desc *rbufs;
302 	unsigned int rbuf_current;
303 	unsigned int rbuf_index;
304 	unsigned int rbuf_fill_index;
305 	unsigned short rbuf_fill_count;
306 
307 	unsigned int tbuf_count;
308 	struct slgt_desc *tbufs;
309 	unsigned int tbuf_current;
310 	unsigned int tbuf_start;
311 
312 	unsigned char *tmp_rbuf;
313 	unsigned int tmp_rbuf_count;
314 
315 	/* SPPP/Cisco HDLC device parts */
316 
317 	int netcount;
318 	spinlock_t netlock;
319 #if SYNCLINK_GENERIC_HDLC
320 	struct net_device *netdev;
321 #endif
322 
323 };
324 
325 static const MGSL_PARAMS default_params = {
326 	.mode            = MGSL_MODE_HDLC,
327 	.loopback        = 0,
328 	.flags           = HDLC_FLAG_UNDERRUN_ABORT15,
329 	.encoding        = HDLC_ENCODING_NRZI_SPACE,
330 	.clock_speed     = 0,
331 	.addr_filter     = 0xff,
332 	.crc_type        = HDLC_CRC_16_CCITT,
333 	.preamble_length = HDLC_PREAMBLE_LENGTH_8BITS,
334 	.preamble        = HDLC_PREAMBLE_PATTERN_NONE,
335 	.data_rate       = 9600,
336 	.data_bits       = 8,
337 	.stop_bits       = 1,
338 	.parity          = ASYNC_PARITY_NONE
339 };
340 
341 
342 #define BH_RECEIVE  1
343 #define BH_TRANSMIT 2
344 #define BH_STATUS   4
345 #define IO_PIN_SHUTDOWN_LIMIT 100
346 
347 #define DMABUFSIZE 256
348 #define DESC_LIST_SIZE 4096
349 
350 #define MASK_PARITY  BIT1
351 #define MASK_FRAMING BIT0
352 #define MASK_BREAK   BIT14
353 #define MASK_OVERRUN BIT4
354 
355 #define GSR   0x00 /* global status */
356 #define JCR   0x04 /* JTAG control */
357 #define IODR  0x08 /* GPIO direction */
358 #define IOER  0x0c /* GPIO interrupt enable */
359 #define IOVR  0x10 /* GPIO value */
360 #define IOSR  0x14 /* GPIO interrupt status */
361 #define TDR   0x80 /* tx data */
362 #define RDR   0x80 /* rx data */
363 #define TCR   0x82 /* tx control */
364 #define TIR   0x84 /* tx idle */
365 #define TPR   0x85 /* tx preamble */
366 #define RCR   0x86 /* rx control */
367 #define VCR   0x88 /* V.24 control */
368 #define CCR   0x89 /* clock control */
369 #define BDR   0x8a /* baud divisor */
370 #define SCR   0x8c /* serial control */
371 #define SSR   0x8e /* serial status */
372 #define RDCSR 0x90 /* rx DMA control/status */
373 #define TDCSR 0x94 /* tx DMA control/status */
374 #define RDDAR 0x98 /* rx DMA descriptor address */
375 #define TDDAR 0x9c /* tx DMA descriptor address */
376 #define XSR   0x40 /* extended sync pattern */
377 #define XCR   0x44 /* extended control */
378 
379 #define RXIDLE      BIT14
380 #define RXBREAK     BIT14
381 #define IRQ_TXDATA  BIT13
382 #define IRQ_TXIDLE  BIT12
383 #define IRQ_TXUNDER BIT11 /* HDLC */
384 #define IRQ_RXDATA  BIT10
385 #define IRQ_RXIDLE  BIT9  /* HDLC */
386 #define IRQ_RXBREAK BIT9  /* async */
387 #define IRQ_RXOVER  BIT8
388 #define IRQ_DSR     BIT7
389 #define IRQ_CTS     BIT6
390 #define IRQ_DCD     BIT5
391 #define IRQ_RI      BIT4
392 #define IRQ_ALL     0x3ff0
393 #define IRQ_MASTER  BIT0
394 
395 #define slgt_irq_on(info, mask) \
396 	wr_reg16((info), SCR, (unsigned short)(rd_reg16((info), SCR) | (mask)))
397 #define slgt_irq_off(info, mask) \
398 	wr_reg16((info), SCR, (unsigned short)(rd_reg16((info), SCR) & ~(mask)))
399 
400 static __u8  rd_reg8(struct slgt_info *info, unsigned int addr);
401 static void  wr_reg8(struct slgt_info *info, unsigned int addr, __u8 value);
402 static __u16 rd_reg16(struct slgt_info *info, unsigned int addr);
403 static void  wr_reg16(struct slgt_info *info, unsigned int addr, __u16 value);
404 static __u32 rd_reg32(struct slgt_info *info, unsigned int addr);
405 static void  wr_reg32(struct slgt_info *info, unsigned int addr, __u32 value);
406 
407 static void  msc_set_vcr(struct slgt_info *info);
408 
409 static int  startup(struct slgt_info *info);
410 static int  block_til_ready(struct tty_struct *tty, struct file * filp,struct slgt_info *info);
411 static void shutdown(struct slgt_info *info);
412 static void program_hw(struct slgt_info *info);
413 static void change_params(struct slgt_info *info);
414 
415 static int  adapter_test(struct slgt_info *info);
416 
417 static void reset_port(struct slgt_info *info);
418 static void async_mode(struct slgt_info *info);
419 static void sync_mode(struct slgt_info *info);
420 
421 static void rx_stop(struct slgt_info *info);
422 static void rx_start(struct slgt_info *info);
423 static void reset_rbufs(struct slgt_info *info);
424 static void free_rbufs(struct slgt_info *info, unsigned int first, unsigned int last);
425 static bool rx_get_frame(struct slgt_info *info);
426 static bool rx_get_buf(struct slgt_info *info);
427 
428 static void tx_start(struct slgt_info *info);
429 static void tx_stop(struct slgt_info *info);
430 static void tx_set_idle(struct slgt_info *info);
431 static unsigned int tbuf_bytes(struct slgt_info *info);
432 static void reset_tbufs(struct slgt_info *info);
433 static void tdma_reset(struct slgt_info *info);
434 static bool tx_load(struct slgt_info *info, const u8 *buf, unsigned int count);
435 
436 static void get_gtsignals(struct slgt_info *info);
437 static void set_gtsignals(struct slgt_info *info);
438 static void set_rate(struct slgt_info *info, u32 data_rate);
439 
440 static void bh_transmit(struct slgt_info *info);
441 static void isr_txeom(struct slgt_info *info, unsigned short status);
442 
443 static void tx_timeout(struct timer_list *t);
444 static void rx_timeout(struct timer_list *t);
445 
446 /*
447  * ioctl handlers
448  */
449 static int  get_stats(struct slgt_info *info, struct mgsl_icount __user *user_icount);
450 static int  get_params(struct slgt_info *info, MGSL_PARAMS __user *params);
451 static int  set_params(struct slgt_info *info, MGSL_PARAMS __user *params);
452 static int  get_txidle(struct slgt_info *info, int __user *idle_mode);
453 static int  set_txidle(struct slgt_info *info, int idle_mode);
454 static int  tx_enable(struct slgt_info *info, int enable);
455 static int  tx_abort(struct slgt_info *info);
456 static int  rx_enable(struct slgt_info *info, int enable);
457 static int  modem_input_wait(struct slgt_info *info,int arg);
458 static int  wait_mgsl_event(struct slgt_info *info, int __user *mask_ptr);
459 static int  get_interface(struct slgt_info *info, int __user *if_mode);
460 static int  set_interface(struct slgt_info *info, int if_mode);
461 static int  set_gpio(struct slgt_info *info, struct gpio_desc __user *gpio);
462 static int  get_gpio(struct slgt_info *info, struct gpio_desc __user *gpio);
463 static int  wait_gpio(struct slgt_info *info, struct gpio_desc __user *gpio);
464 static int  get_xsync(struct slgt_info *info, int __user *if_mode);
465 static int  set_xsync(struct slgt_info *info, int if_mode);
466 static int  get_xctrl(struct slgt_info *info, int __user *if_mode);
467 static int  set_xctrl(struct slgt_info *info, int if_mode);
468 
469 /*
470  * driver functions
471  */
472 static void release_resources(struct slgt_info *info);
473 
474 /*
475  * DEBUG OUTPUT CODE
476  */
477 #ifndef DBGINFO
478 #define DBGINFO(fmt)
479 #endif
480 #ifndef DBGERR
481 #define DBGERR(fmt)
482 #endif
483 #ifndef DBGBH
484 #define DBGBH(fmt)
485 #endif
486 #ifndef DBGISR
487 #define DBGISR(fmt)
488 #endif
489 
490 #ifdef DBGDATA
491 static void trace_block(struct slgt_info *info, const char *data, int count, const char *label)
492 {
493 	int i;
494 	int linecount;
495 	printk("%s %s data:\n",info->device_name, label);
496 	while(count) {
497 		linecount = (count > 16) ? 16 : count;
498 		for(i=0; i < linecount; i++)
499 			printk("%02X ",(unsigned char)data[i]);
500 		for(;i<17;i++)
501 			printk("   ");
502 		for(i=0;i<linecount;i++) {
503 			if (data[i]>=040 && data[i]<=0176)
504 				printk("%c",data[i]);
505 			else
506 				printk(".");
507 		}
508 		printk("\n");
509 		data  += linecount;
510 		count -= linecount;
511 	}
512 }
513 #else
514 #define DBGDATA(info, buf, size, label)
515 #endif
516 
517 #ifdef DBGTBUF
518 static void dump_tbufs(struct slgt_info *info)
519 {
520 	int i;
521 	printk("tbuf_current=%d\n", info->tbuf_current);
522 	for (i=0 ; i < info->tbuf_count ; i++) {
523 		printk("%d: count=%04X status=%04X\n",
524 			i, le16_to_cpu(info->tbufs[i].count), le16_to_cpu(info->tbufs[i].status));
525 	}
526 }
527 #else
528 #define DBGTBUF(info)
529 #endif
530 
531 #ifdef DBGRBUF
532 static void dump_rbufs(struct slgt_info *info)
533 {
534 	int i;
535 	printk("rbuf_current=%d\n", info->rbuf_current);
536 	for (i=0 ; i < info->rbuf_count ; i++) {
537 		printk("%d: count=%04X status=%04X\n",
538 			i, le16_to_cpu(info->rbufs[i].count), le16_to_cpu(info->rbufs[i].status));
539 	}
540 }
541 #else
542 #define DBGRBUF(info)
543 #endif
544 
545 static inline int sanity_check(struct slgt_info *info, char *devname, const char *name)
546 {
547 #ifdef SANITY_CHECK
548 	if (!info) {
549 		printk("null struct slgt_info for (%s) in %s\n", devname, name);
550 		return 1;
551 	}
552 #else
553 	if (!info)
554 		return 1;
555 #endif
556 	return 0;
557 }
558 
559 /*
560  * line discipline callback wrappers
561  *
562  * The wrappers maintain line discipline references
563  * while calling into the line discipline.
564  *
565  * ldisc_receive_buf  - pass receive data to line discipline
566  */
567 static void ldisc_receive_buf(struct tty_struct *tty,
568 			      const __u8 *data, char *flags, int count)
569 {
570 	struct tty_ldisc *ld;
571 	if (!tty)
572 		return;
573 	ld = tty_ldisc_ref(tty);
574 	if (ld) {
575 		if (ld->ops->receive_buf)
576 			ld->ops->receive_buf(tty, data, flags, count);
577 		tty_ldisc_deref(ld);
578 	}
579 }
580 
581 /* tty callbacks */
582 
583 static int open(struct tty_struct *tty, struct file *filp)
584 {
585 	struct slgt_info *info;
586 	int retval, line;
587 	unsigned long flags;
588 
589 	line = tty->index;
590 	if (line >= slgt_device_count) {
591 		DBGERR(("%s: open with invalid line #%d.\n", driver_name, line));
592 		return -ENODEV;
593 	}
594 
595 	info = slgt_device_list;
596 	while(info && info->line != line)
597 		info = info->next_device;
598 	if (sanity_check(info, tty->name, "open"))
599 		return -ENODEV;
600 	if (info->init_error) {
601 		DBGERR(("%s init error=%d\n", info->device_name, info->init_error));
602 		return -ENODEV;
603 	}
604 
605 	tty->driver_data = info;
606 	info->port.tty = tty;
607 
608 	DBGINFO(("%s open, old ref count = %d\n", info->device_name, info->port.count));
609 
610 	mutex_lock(&info->port.mutex);
611 
612 	spin_lock_irqsave(&info->netlock, flags);
613 	if (info->netcount) {
614 		retval = -EBUSY;
615 		spin_unlock_irqrestore(&info->netlock, flags);
616 		mutex_unlock(&info->port.mutex);
617 		goto cleanup;
618 	}
619 	info->port.count++;
620 	spin_unlock_irqrestore(&info->netlock, flags);
621 
622 	if (info->port.count == 1) {
623 		/* 1st open on this device, init hardware */
624 		retval = startup(info);
625 		if (retval < 0) {
626 			mutex_unlock(&info->port.mutex);
627 			goto cleanup;
628 		}
629 	}
630 	mutex_unlock(&info->port.mutex);
631 	retval = block_til_ready(tty, filp, info);
632 	if (retval) {
633 		DBGINFO(("%s block_til_ready rc=%d\n", info->device_name, retval));
634 		goto cleanup;
635 	}
636 
637 	retval = 0;
638 
639 cleanup:
640 	if (retval) {
641 		if (tty->count == 1)
642 			info->port.tty = NULL; /* tty layer will release tty struct */
643 		if(info->port.count)
644 			info->port.count--;
645 	}
646 
647 	DBGINFO(("%s open rc=%d\n", info->device_name, retval));
648 	return retval;
649 }
650 
651 static void close(struct tty_struct *tty, struct file *filp)
652 {
653 	struct slgt_info *info = tty->driver_data;
654 
655 	if (sanity_check(info, tty->name, "close"))
656 		return;
657 	DBGINFO(("%s close entry, count=%d\n", info->device_name, info->port.count));
658 
659 	if (tty_port_close_start(&info->port, tty, filp) == 0)
660 		goto cleanup;
661 
662 	mutex_lock(&info->port.mutex);
663 	if (tty_port_initialized(&info->port))
664  		wait_until_sent(tty, info->timeout);
665 	flush_buffer(tty);
666 	tty_ldisc_flush(tty);
667 
668 	shutdown(info);
669 	mutex_unlock(&info->port.mutex);
670 
671 	tty_port_close_end(&info->port, tty);
672 	info->port.tty = NULL;
673 cleanup:
674 	DBGINFO(("%s close exit, count=%d\n", tty->driver->name, info->port.count));
675 }
676 
677 static void hangup(struct tty_struct *tty)
678 {
679 	struct slgt_info *info = tty->driver_data;
680 	unsigned long flags;
681 
682 	if (sanity_check(info, tty->name, "hangup"))
683 		return;
684 	DBGINFO(("%s hangup\n", info->device_name));
685 
686 	flush_buffer(tty);
687 
688 	mutex_lock(&info->port.mutex);
689 	shutdown(info);
690 
691 	spin_lock_irqsave(&info->port.lock, flags);
692 	info->port.count = 0;
693 	info->port.tty = NULL;
694 	spin_unlock_irqrestore(&info->port.lock, flags);
695 	tty_port_set_active(&info->port, false);
696 	mutex_unlock(&info->port.mutex);
697 
698 	wake_up_interruptible(&info->port.open_wait);
699 }
700 
701 static void set_termios(struct tty_struct *tty,
702 			const struct ktermios *old_termios)
703 {
704 	struct slgt_info *info = tty->driver_data;
705 	unsigned long flags;
706 
707 	DBGINFO(("%s set_termios\n", tty->driver->name));
708 
709 	change_params(info);
710 
711 	/* Handle transition to B0 status */
712 	if ((old_termios->c_cflag & CBAUD) && !C_BAUD(tty)) {
713 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
714 		spin_lock_irqsave(&info->lock,flags);
715 		set_gtsignals(info);
716 		spin_unlock_irqrestore(&info->lock,flags);
717 	}
718 
719 	/* Handle transition away from B0 status */
720 	if (!(old_termios->c_cflag & CBAUD) && C_BAUD(tty)) {
721 		info->signals |= SerialSignal_DTR;
722 		if (!C_CRTSCTS(tty) || !tty_throttled(tty))
723 			info->signals |= SerialSignal_RTS;
724 		spin_lock_irqsave(&info->lock,flags);
725 	 	set_gtsignals(info);
726 		spin_unlock_irqrestore(&info->lock,flags);
727 	}
728 
729 	/* Handle turning off CRTSCTS */
730 	if ((old_termios->c_cflag & CRTSCTS) && !C_CRTSCTS(tty)) {
731 		tty->hw_stopped = false;
732 		tx_release(tty);
733 	}
734 }
735 
736 static void update_tx_timer(struct slgt_info *info)
737 {
738 	/*
739 	 * use worst case speed of 1200bps to calculate transmit timeout
740 	 * based on data in buffers (tbuf_bytes) and FIFO (128 bytes)
741 	 */
742 	if (info->params.mode == MGSL_MODE_HDLC) {
743 		int timeout  = (tbuf_bytes(info) * 7) + 1000;
744 		mod_timer(&info->tx_timer, jiffies + msecs_to_jiffies(timeout));
745 	}
746 }
747 
748 static ssize_t write(struct tty_struct *tty, const u8 *buf, size_t count)
749 {
750 	int ret = 0;
751 	struct slgt_info *info = tty->driver_data;
752 	unsigned long flags;
753 
754 	if (sanity_check(info, tty->name, "write"))
755 		return -EIO;
756 
757 	DBGINFO(("%s write count=%zu\n", info->device_name, count));
758 
759 	if (!info->tx_buf || (count > info->max_frame_size))
760 		return -EIO;
761 
762 	if (!count || tty->flow.stopped || tty->hw_stopped)
763 		return 0;
764 
765 	spin_lock_irqsave(&info->lock, flags);
766 
767 	if (info->tx_count) {
768 		/* send accumulated data from send_char() */
769 		if (!tx_load(info, info->tx_buf, info->tx_count))
770 			goto cleanup;
771 		info->tx_count = 0;
772 	}
773 
774 	if (tx_load(info, buf, count))
775 		ret = count;
776 
777 cleanup:
778 	spin_unlock_irqrestore(&info->lock, flags);
779 	DBGINFO(("%s write rc=%d\n", info->device_name, ret));
780 	return ret;
781 }
782 
783 static int put_char(struct tty_struct *tty, u8 ch)
784 {
785 	struct slgt_info *info = tty->driver_data;
786 	unsigned long flags;
787 	int ret = 0;
788 
789 	if (sanity_check(info, tty->name, "put_char"))
790 		return 0;
791 	DBGINFO(("%s put_char(%u)\n", info->device_name, ch));
792 	if (!info->tx_buf)
793 		return 0;
794 	spin_lock_irqsave(&info->lock,flags);
795 	if (info->tx_count < info->max_frame_size) {
796 		info->tx_buf[info->tx_count++] = ch;
797 		ret = 1;
798 	}
799 	spin_unlock_irqrestore(&info->lock,flags);
800 	return ret;
801 }
802 
803 static void send_xchar(struct tty_struct *tty, char ch)
804 {
805 	struct slgt_info *info = tty->driver_data;
806 	unsigned long flags;
807 
808 	if (sanity_check(info, tty->name, "send_xchar"))
809 		return;
810 	DBGINFO(("%s send_xchar(%d)\n", info->device_name, ch));
811 	info->x_char = ch;
812 	if (ch) {
813 		spin_lock_irqsave(&info->lock,flags);
814 		if (!info->tx_enabled)
815 		 	tx_start(info);
816 		spin_unlock_irqrestore(&info->lock,flags);
817 	}
818 }
819 
820 static void wait_until_sent(struct tty_struct *tty, int timeout)
821 {
822 	struct slgt_info *info = tty->driver_data;
823 	unsigned long orig_jiffies, char_time;
824 
825 	if (!info )
826 		return;
827 	if (sanity_check(info, tty->name, "wait_until_sent"))
828 		return;
829 	DBGINFO(("%s wait_until_sent entry\n", info->device_name));
830 	if (!tty_port_initialized(&info->port))
831 		goto exit;
832 
833 	orig_jiffies = jiffies;
834 
835 	/* Set check interval to 1/5 of estimated time to
836 	 * send a character, and make it at least 1. The check
837 	 * interval should also be less than the timeout.
838 	 * Note: use tight timings here to satisfy the NIST-PCTS.
839 	 */
840 
841 	if (info->params.data_rate) {
842 	       	char_time = info->timeout/(32 * 5);
843 		if (!char_time)
844 			char_time++;
845 	} else
846 		char_time = 1;
847 
848 	if (timeout)
849 		char_time = min_t(unsigned long, char_time, timeout);
850 
851 	while (info->tx_active) {
852 		msleep_interruptible(jiffies_to_msecs(char_time));
853 		if (signal_pending(current))
854 			break;
855 		if (timeout && time_after(jiffies, orig_jiffies + timeout))
856 			break;
857 	}
858 exit:
859 	DBGINFO(("%s wait_until_sent exit\n", info->device_name));
860 }
861 
862 static unsigned int write_room(struct tty_struct *tty)
863 {
864 	struct slgt_info *info = tty->driver_data;
865 	unsigned int ret;
866 
867 	if (sanity_check(info, tty->name, "write_room"))
868 		return 0;
869 	ret = (info->tx_active) ? 0 : HDLC_MAX_FRAME_SIZE;
870 	DBGINFO(("%s write_room=%u\n", info->device_name, ret));
871 	return ret;
872 }
873 
874 static void flush_chars(struct tty_struct *tty)
875 {
876 	struct slgt_info *info = tty->driver_data;
877 	unsigned long flags;
878 
879 	if (sanity_check(info, tty->name, "flush_chars"))
880 		return;
881 	DBGINFO(("%s flush_chars entry tx_count=%d\n", info->device_name, info->tx_count));
882 
883 	if (info->tx_count <= 0 || tty->flow.stopped ||
884 	    tty->hw_stopped || !info->tx_buf)
885 		return;
886 
887 	DBGINFO(("%s flush_chars start transmit\n", info->device_name));
888 
889 	spin_lock_irqsave(&info->lock,flags);
890 	if (info->tx_count && tx_load(info, info->tx_buf, info->tx_count))
891 		info->tx_count = 0;
892 	spin_unlock_irqrestore(&info->lock,flags);
893 }
894 
895 static void flush_buffer(struct tty_struct *tty)
896 {
897 	struct slgt_info *info = tty->driver_data;
898 	unsigned long flags;
899 
900 	if (sanity_check(info, tty->name, "flush_buffer"))
901 		return;
902 	DBGINFO(("%s flush_buffer\n", info->device_name));
903 
904 	spin_lock_irqsave(&info->lock, flags);
905 	info->tx_count = 0;
906 	spin_unlock_irqrestore(&info->lock, flags);
907 
908 	tty_wakeup(tty);
909 }
910 
911 /*
912  * throttle (stop) transmitter
913  */
914 static void tx_hold(struct tty_struct *tty)
915 {
916 	struct slgt_info *info = tty->driver_data;
917 	unsigned long flags;
918 
919 	if (sanity_check(info, tty->name, "tx_hold"))
920 		return;
921 	DBGINFO(("%s tx_hold\n", info->device_name));
922 	spin_lock_irqsave(&info->lock,flags);
923 	if (info->tx_enabled && info->params.mode == MGSL_MODE_ASYNC)
924 	 	tx_stop(info);
925 	spin_unlock_irqrestore(&info->lock,flags);
926 }
927 
928 /*
929  * release (start) transmitter
930  */
931 static void tx_release(struct tty_struct *tty)
932 {
933 	struct slgt_info *info = tty->driver_data;
934 	unsigned long flags;
935 
936 	if (sanity_check(info, tty->name, "tx_release"))
937 		return;
938 	DBGINFO(("%s tx_release\n", info->device_name));
939 	spin_lock_irqsave(&info->lock, flags);
940 	if (info->tx_count && tx_load(info, info->tx_buf, info->tx_count))
941 		info->tx_count = 0;
942 	spin_unlock_irqrestore(&info->lock, flags);
943 }
944 
945 /*
946  * Service an IOCTL request
947  *
948  * Arguments
949  *
950  * 	tty	pointer to tty instance data
951  * 	cmd	IOCTL command code
952  * 	arg	command argument/context
953  *
954  * Return 0 if success, otherwise error code
955  */
956 static int ioctl(struct tty_struct *tty,
957 		 unsigned int cmd, unsigned long arg)
958 {
959 	struct slgt_info *info = tty->driver_data;
960 	void __user *argp = (void __user *)arg;
961 	int ret;
962 
963 	if (sanity_check(info, tty->name, "ioctl"))
964 		return -ENODEV;
965 	DBGINFO(("%s ioctl() cmd=%08X\n", info->device_name, cmd));
966 
967 	if (cmd != TIOCMIWAIT) {
968 		if (tty_io_error(tty))
969 		    return -EIO;
970 	}
971 
972 	switch (cmd) {
973 	case MGSL_IOCWAITEVENT:
974 		return wait_mgsl_event(info, argp);
975 	case TIOCMIWAIT:
976 		return modem_input_wait(info,(int)arg);
977 	case MGSL_IOCSGPIO:
978 		return set_gpio(info, argp);
979 	case MGSL_IOCGGPIO:
980 		return get_gpio(info, argp);
981 	case MGSL_IOCWAITGPIO:
982 		return wait_gpio(info, argp);
983 	case MGSL_IOCGXSYNC:
984 		return get_xsync(info, argp);
985 	case MGSL_IOCSXSYNC:
986 		return set_xsync(info, (int)arg);
987 	case MGSL_IOCGXCTRL:
988 		return get_xctrl(info, argp);
989 	case MGSL_IOCSXCTRL:
990 		return set_xctrl(info, (int)arg);
991 	}
992 	mutex_lock(&info->port.mutex);
993 	switch (cmd) {
994 	case MGSL_IOCGPARAMS:
995 		ret = get_params(info, argp);
996 		break;
997 	case MGSL_IOCSPARAMS:
998 		ret = set_params(info, argp);
999 		break;
1000 	case MGSL_IOCGTXIDLE:
1001 		ret = get_txidle(info, argp);
1002 		break;
1003 	case MGSL_IOCSTXIDLE:
1004 		ret = set_txidle(info, (int)arg);
1005 		break;
1006 	case MGSL_IOCTXENABLE:
1007 		ret = tx_enable(info, (int)arg);
1008 		break;
1009 	case MGSL_IOCRXENABLE:
1010 		ret = rx_enable(info, (int)arg);
1011 		break;
1012 	case MGSL_IOCTXABORT:
1013 		ret = tx_abort(info);
1014 		break;
1015 	case MGSL_IOCGSTATS:
1016 		ret = get_stats(info, argp);
1017 		break;
1018 	case MGSL_IOCGIF:
1019 		ret = get_interface(info, argp);
1020 		break;
1021 	case MGSL_IOCSIF:
1022 		ret = set_interface(info,(int)arg);
1023 		break;
1024 	default:
1025 		ret = -ENOIOCTLCMD;
1026 	}
1027 	mutex_unlock(&info->port.mutex);
1028 	return ret;
1029 }
1030 
1031 static int get_icount(struct tty_struct *tty,
1032 				struct serial_icounter_struct *icount)
1033 
1034 {
1035 	struct slgt_info *info = tty->driver_data;
1036 	struct mgsl_icount cnow;	/* kernel counter temps */
1037 	unsigned long flags;
1038 
1039 	spin_lock_irqsave(&info->lock,flags);
1040 	cnow = info->icount;
1041 	spin_unlock_irqrestore(&info->lock,flags);
1042 
1043 	icount->cts = cnow.cts;
1044 	icount->dsr = cnow.dsr;
1045 	icount->rng = cnow.rng;
1046 	icount->dcd = cnow.dcd;
1047 	icount->rx = cnow.rx;
1048 	icount->tx = cnow.tx;
1049 	icount->frame = cnow.frame;
1050 	icount->overrun = cnow.overrun;
1051 	icount->parity = cnow.parity;
1052 	icount->brk = cnow.brk;
1053 	icount->buf_overrun = cnow.buf_overrun;
1054 
1055 	return 0;
1056 }
1057 
1058 /*
1059  * support for 32 bit ioctl calls on 64 bit systems
1060  */
1061 #ifdef CONFIG_COMPAT
1062 static long get_params32(struct slgt_info *info, struct MGSL_PARAMS32 __user *user_params)
1063 {
1064 	struct MGSL_PARAMS32 tmp_params;
1065 
1066 	DBGINFO(("%s get_params32\n", info->device_name));
1067 	memset(&tmp_params, 0, sizeof(tmp_params));
1068 	tmp_params.mode            = (compat_ulong_t)info->params.mode;
1069 	tmp_params.loopback        = info->params.loopback;
1070 	tmp_params.flags           = info->params.flags;
1071 	tmp_params.encoding        = info->params.encoding;
1072 	tmp_params.clock_speed     = (compat_ulong_t)info->params.clock_speed;
1073 	tmp_params.addr_filter     = info->params.addr_filter;
1074 	tmp_params.crc_type        = info->params.crc_type;
1075 	tmp_params.preamble_length = info->params.preamble_length;
1076 	tmp_params.preamble        = info->params.preamble;
1077 	tmp_params.data_rate       = (compat_ulong_t)info->params.data_rate;
1078 	tmp_params.data_bits       = info->params.data_bits;
1079 	tmp_params.stop_bits       = info->params.stop_bits;
1080 	tmp_params.parity          = info->params.parity;
1081 	if (copy_to_user(user_params, &tmp_params, sizeof(struct MGSL_PARAMS32)))
1082 		return -EFAULT;
1083 	return 0;
1084 }
1085 
1086 static long set_params32(struct slgt_info *info, struct MGSL_PARAMS32 __user *new_params)
1087 {
1088 	struct MGSL_PARAMS32 tmp_params;
1089 	unsigned long flags;
1090 
1091 	DBGINFO(("%s set_params32\n", info->device_name));
1092 	if (copy_from_user(&tmp_params, new_params, sizeof(struct MGSL_PARAMS32)))
1093 		return -EFAULT;
1094 
1095 	spin_lock_irqsave(&info->lock, flags);
1096 	if (tmp_params.mode == MGSL_MODE_BASE_CLOCK) {
1097 		info->base_clock = tmp_params.clock_speed;
1098 	} else {
1099 		info->params.mode            = tmp_params.mode;
1100 		info->params.loopback        = tmp_params.loopback;
1101 		info->params.flags           = tmp_params.flags;
1102 		info->params.encoding        = tmp_params.encoding;
1103 		info->params.clock_speed     = tmp_params.clock_speed;
1104 		info->params.addr_filter     = tmp_params.addr_filter;
1105 		info->params.crc_type        = tmp_params.crc_type;
1106 		info->params.preamble_length = tmp_params.preamble_length;
1107 		info->params.preamble        = tmp_params.preamble;
1108 		info->params.data_rate       = tmp_params.data_rate;
1109 		info->params.data_bits       = tmp_params.data_bits;
1110 		info->params.stop_bits       = tmp_params.stop_bits;
1111 		info->params.parity          = tmp_params.parity;
1112 	}
1113 	spin_unlock_irqrestore(&info->lock, flags);
1114 
1115 	program_hw(info);
1116 
1117 	return 0;
1118 }
1119 
1120 static long slgt_compat_ioctl(struct tty_struct *tty,
1121 			 unsigned int cmd, unsigned long arg)
1122 {
1123 	struct slgt_info *info = tty->driver_data;
1124 	int rc;
1125 
1126 	if (sanity_check(info, tty->name, "compat_ioctl"))
1127 		return -ENODEV;
1128 	DBGINFO(("%s compat_ioctl() cmd=%08X\n", info->device_name, cmd));
1129 
1130 	switch (cmd) {
1131 	case MGSL_IOCSPARAMS32:
1132 		rc = set_params32(info, compat_ptr(arg));
1133 		break;
1134 
1135 	case MGSL_IOCGPARAMS32:
1136 		rc = get_params32(info, compat_ptr(arg));
1137 		break;
1138 
1139 	case MGSL_IOCGPARAMS:
1140 	case MGSL_IOCSPARAMS:
1141 	case MGSL_IOCGTXIDLE:
1142 	case MGSL_IOCGSTATS:
1143 	case MGSL_IOCWAITEVENT:
1144 	case MGSL_IOCGIF:
1145 	case MGSL_IOCSGPIO:
1146 	case MGSL_IOCGGPIO:
1147 	case MGSL_IOCWAITGPIO:
1148 	case MGSL_IOCGXSYNC:
1149 	case MGSL_IOCGXCTRL:
1150 		rc = ioctl(tty, cmd, (unsigned long)compat_ptr(arg));
1151 		break;
1152 	default:
1153 		rc = ioctl(tty, cmd, arg);
1154 	}
1155 	DBGINFO(("%s compat_ioctl() cmd=%08X rc=%d\n", info->device_name, cmd, rc));
1156 	return rc;
1157 }
1158 #else
1159 #define slgt_compat_ioctl NULL
1160 #endif /* ifdef CONFIG_COMPAT */
1161 
1162 /*
1163  * proc fs support
1164  */
1165 static inline void line_info(struct seq_file *m, struct slgt_info *info)
1166 {
1167 	char stat_buf[30];
1168 	unsigned long flags;
1169 
1170 	seq_printf(m, "%s: IO=%08X IRQ=%d MaxFrameSize=%u\n",
1171 		      info->device_name, info->phys_reg_addr,
1172 		      info->irq_level, info->max_frame_size);
1173 
1174 	/* output current serial signal states */
1175 	spin_lock_irqsave(&info->lock,flags);
1176 	get_gtsignals(info);
1177 	spin_unlock_irqrestore(&info->lock,flags);
1178 
1179 	stat_buf[0] = 0;
1180 	stat_buf[1] = 0;
1181 	if (info->signals & SerialSignal_RTS)
1182 		strcat(stat_buf, "|RTS");
1183 	if (info->signals & SerialSignal_CTS)
1184 		strcat(stat_buf, "|CTS");
1185 	if (info->signals & SerialSignal_DTR)
1186 		strcat(stat_buf, "|DTR");
1187 	if (info->signals & SerialSignal_DSR)
1188 		strcat(stat_buf, "|DSR");
1189 	if (info->signals & SerialSignal_DCD)
1190 		strcat(stat_buf, "|CD");
1191 	if (info->signals & SerialSignal_RI)
1192 		strcat(stat_buf, "|RI");
1193 
1194 	if (info->params.mode != MGSL_MODE_ASYNC) {
1195 		seq_printf(m, "\tHDLC txok:%d rxok:%d",
1196 			       info->icount.txok, info->icount.rxok);
1197 		if (info->icount.txunder)
1198 			seq_printf(m, " txunder:%d", info->icount.txunder);
1199 		if (info->icount.txabort)
1200 			seq_printf(m, " txabort:%d", info->icount.txabort);
1201 		if (info->icount.rxshort)
1202 			seq_printf(m, " rxshort:%d", info->icount.rxshort);
1203 		if (info->icount.rxlong)
1204 			seq_printf(m, " rxlong:%d", info->icount.rxlong);
1205 		if (info->icount.rxover)
1206 			seq_printf(m, " rxover:%d", info->icount.rxover);
1207 		if (info->icount.rxcrc)
1208 			seq_printf(m, " rxcrc:%d", info->icount.rxcrc);
1209 	} else {
1210 		seq_printf(m, "\tASYNC tx:%d rx:%d",
1211 			       info->icount.tx, info->icount.rx);
1212 		if (info->icount.frame)
1213 			seq_printf(m, " fe:%d", info->icount.frame);
1214 		if (info->icount.parity)
1215 			seq_printf(m, " pe:%d", info->icount.parity);
1216 		if (info->icount.brk)
1217 			seq_printf(m, " brk:%d", info->icount.brk);
1218 		if (info->icount.overrun)
1219 			seq_printf(m, " oe:%d", info->icount.overrun);
1220 	}
1221 
1222 	/* Append serial signal status to end */
1223 	seq_printf(m, " %s\n", stat_buf+1);
1224 
1225 	seq_printf(m, "\ttxactive=%d bh_req=%d bh_run=%d pending_bh=%x\n",
1226 		       info->tx_active,info->bh_requested,info->bh_running,
1227 		       info->pending_bh);
1228 }
1229 
1230 /* Called to print information about devices
1231  */
1232 static int synclink_gt_proc_show(struct seq_file *m, void *v)
1233 {
1234 	struct slgt_info *info;
1235 
1236 	seq_puts(m, "synclink_gt driver\n");
1237 
1238 	info = slgt_device_list;
1239 	while( info ) {
1240 		line_info(m, info);
1241 		info = info->next_device;
1242 	}
1243 	return 0;
1244 }
1245 
1246 /*
1247  * return count of bytes in transmit buffer
1248  */
1249 static unsigned int chars_in_buffer(struct tty_struct *tty)
1250 {
1251 	struct slgt_info *info = tty->driver_data;
1252 	unsigned int count;
1253 	if (sanity_check(info, tty->name, "chars_in_buffer"))
1254 		return 0;
1255 	count = tbuf_bytes(info);
1256 	DBGINFO(("%s chars_in_buffer()=%u\n", info->device_name, count));
1257 	return count;
1258 }
1259 
1260 /*
1261  * signal remote device to throttle send data (our receive data)
1262  */
1263 static void throttle(struct tty_struct * tty)
1264 {
1265 	struct slgt_info *info = tty->driver_data;
1266 	unsigned long flags;
1267 
1268 	if (sanity_check(info, tty->name, "throttle"))
1269 		return;
1270 	DBGINFO(("%s throttle\n", info->device_name));
1271 	if (I_IXOFF(tty))
1272 		send_xchar(tty, STOP_CHAR(tty));
1273 	if (C_CRTSCTS(tty)) {
1274 		spin_lock_irqsave(&info->lock,flags);
1275 		info->signals &= ~SerialSignal_RTS;
1276 		set_gtsignals(info);
1277 		spin_unlock_irqrestore(&info->lock,flags);
1278 	}
1279 }
1280 
1281 /*
1282  * signal remote device to stop throttling send data (our receive data)
1283  */
1284 static void unthrottle(struct tty_struct * tty)
1285 {
1286 	struct slgt_info *info = tty->driver_data;
1287 	unsigned long flags;
1288 
1289 	if (sanity_check(info, tty->name, "unthrottle"))
1290 		return;
1291 	DBGINFO(("%s unthrottle\n", info->device_name));
1292 	if (I_IXOFF(tty)) {
1293 		if (info->x_char)
1294 			info->x_char = 0;
1295 		else
1296 			send_xchar(tty, START_CHAR(tty));
1297 	}
1298 	if (C_CRTSCTS(tty)) {
1299 		spin_lock_irqsave(&info->lock,flags);
1300 		info->signals |= SerialSignal_RTS;
1301 		set_gtsignals(info);
1302 		spin_unlock_irqrestore(&info->lock,flags);
1303 	}
1304 }
1305 
1306 /*
1307  * set or clear transmit break condition
1308  * break_state	-1=set break condition, 0=clear
1309  */
1310 static int set_break(struct tty_struct *tty, int break_state)
1311 {
1312 	struct slgt_info *info = tty->driver_data;
1313 	unsigned short value;
1314 	unsigned long flags;
1315 
1316 	if (sanity_check(info, tty->name, "set_break"))
1317 		return -EINVAL;
1318 	DBGINFO(("%s set_break(%d)\n", info->device_name, break_state));
1319 
1320 	spin_lock_irqsave(&info->lock,flags);
1321 	value = rd_reg16(info, TCR);
1322  	if (break_state == -1)
1323 		value |= BIT6;
1324 	else
1325 		value &= ~BIT6;
1326 	wr_reg16(info, TCR, value);
1327 	spin_unlock_irqrestore(&info->lock,flags);
1328 	return 0;
1329 }
1330 
1331 #if SYNCLINK_GENERIC_HDLC
1332 
1333 /**
1334  * hdlcdev_attach - called by generic HDLC layer when protocol selected (PPP, frame relay, etc.)
1335  * @dev:      pointer to network device structure
1336  * @encoding: serial encoding setting
1337  * @parity:   FCS setting
1338  *
1339  * Set encoding and frame check sequence (FCS) options.
1340  *
1341  * Return: 0 if success, otherwise error code
1342  */
1343 static int hdlcdev_attach(struct net_device *dev, unsigned short encoding,
1344 			  unsigned short parity)
1345 {
1346 	struct slgt_info *info = dev_to_port(dev);
1347 	unsigned char  new_encoding;
1348 	unsigned short new_crctype;
1349 
1350 	/* return error if TTY interface open */
1351 	if (info->port.count)
1352 		return -EBUSY;
1353 
1354 	DBGINFO(("%s hdlcdev_attach\n", info->device_name));
1355 
1356 	switch (encoding)
1357 	{
1358 	case ENCODING_NRZ:        new_encoding = HDLC_ENCODING_NRZ; break;
1359 	case ENCODING_NRZI:       new_encoding = HDLC_ENCODING_NRZI_SPACE; break;
1360 	case ENCODING_FM_MARK:    new_encoding = HDLC_ENCODING_BIPHASE_MARK; break;
1361 	case ENCODING_FM_SPACE:   new_encoding = HDLC_ENCODING_BIPHASE_SPACE; break;
1362 	case ENCODING_MANCHESTER: new_encoding = HDLC_ENCODING_BIPHASE_LEVEL; break;
1363 	default: return -EINVAL;
1364 	}
1365 
1366 	switch (parity)
1367 	{
1368 	case PARITY_NONE:            new_crctype = HDLC_CRC_NONE; break;
1369 	case PARITY_CRC16_PR1_CCITT: new_crctype = HDLC_CRC_16_CCITT; break;
1370 	case PARITY_CRC32_PR1_CCITT: new_crctype = HDLC_CRC_32_CCITT; break;
1371 	default: return -EINVAL;
1372 	}
1373 
1374 	info->params.encoding = new_encoding;
1375 	info->params.crc_type = new_crctype;
1376 
1377 	/* if network interface up, reprogram hardware */
1378 	if (info->netcount)
1379 		program_hw(info);
1380 
1381 	return 0;
1382 }
1383 
1384 /**
1385  * hdlcdev_xmit - called by generic HDLC layer to send a frame
1386  * @skb: socket buffer containing HDLC frame
1387  * @dev: pointer to network device structure
1388  */
1389 static netdev_tx_t hdlcdev_xmit(struct sk_buff *skb,
1390 				      struct net_device *dev)
1391 {
1392 	struct slgt_info *info = dev_to_port(dev);
1393 	unsigned long flags;
1394 
1395 	DBGINFO(("%s hdlc_xmit\n", dev->name));
1396 
1397 	if (!skb->len)
1398 		return NETDEV_TX_OK;
1399 
1400 	/* stop sending until this frame completes */
1401 	netif_stop_queue(dev);
1402 
1403 	/* update network statistics */
1404 	dev->stats.tx_packets++;
1405 	dev->stats.tx_bytes += skb->len;
1406 
1407 	/* save start time for transmit timeout detection */
1408 	netif_trans_update(dev);
1409 
1410 	spin_lock_irqsave(&info->lock, flags);
1411 	tx_load(info, skb->data, skb->len);
1412 	spin_unlock_irqrestore(&info->lock, flags);
1413 
1414 	/* done with socket buffer, so free it */
1415 	dev_kfree_skb(skb);
1416 
1417 	return NETDEV_TX_OK;
1418 }
1419 
1420 /**
1421  * hdlcdev_open - called by network layer when interface enabled
1422  * @dev: pointer to network device structure
1423  *
1424  * Claim resources and initialize hardware.
1425  *
1426  * Return: 0 if success, otherwise error code
1427  */
1428 static int hdlcdev_open(struct net_device *dev)
1429 {
1430 	struct slgt_info *info = dev_to_port(dev);
1431 	int rc;
1432 	unsigned long flags;
1433 
1434 	DBGINFO(("%s hdlcdev_open\n", dev->name));
1435 
1436 	/* arbitrate between network and tty opens */
1437 	spin_lock_irqsave(&info->netlock, flags);
1438 	if (info->port.count != 0 || info->netcount != 0) {
1439 		DBGINFO(("%s hdlc_open busy\n", dev->name));
1440 		spin_unlock_irqrestore(&info->netlock, flags);
1441 		return -EBUSY;
1442 	}
1443 	info->netcount=1;
1444 	spin_unlock_irqrestore(&info->netlock, flags);
1445 
1446 	/* claim resources and init adapter */
1447 	if ((rc = startup(info)) != 0) {
1448 		spin_lock_irqsave(&info->netlock, flags);
1449 		info->netcount=0;
1450 		spin_unlock_irqrestore(&info->netlock, flags);
1451 		return rc;
1452 	}
1453 
1454 	/* generic HDLC layer open processing */
1455 	rc = hdlc_open(dev);
1456 	if (rc) {
1457 		shutdown(info);
1458 		spin_lock_irqsave(&info->netlock, flags);
1459 		info->netcount = 0;
1460 		spin_unlock_irqrestore(&info->netlock, flags);
1461 		return rc;
1462 	}
1463 
1464 	/* assert RTS and DTR, apply hardware settings */
1465 	info->signals |= SerialSignal_RTS | SerialSignal_DTR;
1466 	program_hw(info);
1467 
1468 	/* enable network layer transmit */
1469 	netif_trans_update(dev);
1470 	netif_start_queue(dev);
1471 
1472 	/* inform generic HDLC layer of current DCD status */
1473 	spin_lock_irqsave(&info->lock, flags);
1474 	get_gtsignals(info);
1475 	spin_unlock_irqrestore(&info->lock, flags);
1476 	if (info->signals & SerialSignal_DCD)
1477 		netif_carrier_on(dev);
1478 	else
1479 		netif_carrier_off(dev);
1480 	return 0;
1481 }
1482 
1483 /**
1484  * hdlcdev_close - called by network layer when interface is disabled
1485  * @dev:  pointer to network device structure
1486  *
1487  * Shutdown hardware and release resources.
1488  *
1489  * Return: 0 if success, otherwise error code
1490  */
1491 static int hdlcdev_close(struct net_device *dev)
1492 {
1493 	struct slgt_info *info = dev_to_port(dev);
1494 	unsigned long flags;
1495 
1496 	DBGINFO(("%s hdlcdev_close\n", dev->name));
1497 
1498 	netif_stop_queue(dev);
1499 
1500 	/* shutdown adapter and release resources */
1501 	shutdown(info);
1502 
1503 	hdlc_close(dev);
1504 
1505 	spin_lock_irqsave(&info->netlock, flags);
1506 	info->netcount=0;
1507 	spin_unlock_irqrestore(&info->netlock, flags);
1508 
1509 	return 0;
1510 }
1511 
1512 /**
1513  * hdlcdev_ioctl - called by network layer to process IOCTL call to network device
1514  * @dev: pointer to network device structure
1515  * @ifr: pointer to network interface request structure
1516  * @cmd: IOCTL command code
1517  *
1518  * Return: 0 if success, otherwise error code
1519  */
1520 static int hdlcdev_ioctl(struct net_device *dev, struct if_settings *ifs)
1521 {
1522 	const size_t size = sizeof(sync_serial_settings);
1523 	sync_serial_settings new_line;
1524 	sync_serial_settings __user *line = ifs->ifs_ifsu.sync;
1525 	struct slgt_info *info = dev_to_port(dev);
1526 	unsigned int flags;
1527 
1528 	DBGINFO(("%s hdlcdev_ioctl\n", dev->name));
1529 
1530 	/* return error if TTY interface open */
1531 	if (info->port.count)
1532 		return -EBUSY;
1533 
1534 	memset(&new_line, 0, sizeof(new_line));
1535 
1536 	switch (ifs->type) {
1537 	case IF_GET_IFACE: /* return current sync_serial_settings */
1538 
1539 		ifs->type = IF_IFACE_SYNC_SERIAL;
1540 		if (ifs->size < size) {
1541 			ifs->size = size; /* data size wanted */
1542 			return -ENOBUFS;
1543 		}
1544 
1545 		flags = info->params.flags & (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
1546 					      HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
1547 					      HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
1548 					      HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN);
1549 
1550 		switch (flags){
1551 		case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_TXCPIN): new_line.clock_type = CLOCK_EXT; break;
1552 		case (HDLC_FLAG_RXC_BRG    | HDLC_FLAG_TXC_BRG):    new_line.clock_type = CLOCK_INT; break;
1553 		case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_BRG):    new_line.clock_type = CLOCK_TXINT; break;
1554 		case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_RXCPIN): new_line.clock_type = CLOCK_TXFROMRX; break;
1555 		default: new_line.clock_type = CLOCK_DEFAULT;
1556 		}
1557 
1558 		new_line.clock_rate = info->params.clock_speed;
1559 		new_line.loopback   = info->params.loopback ? 1:0;
1560 
1561 		if (copy_to_user(line, &new_line, size))
1562 			return -EFAULT;
1563 		return 0;
1564 
1565 	case IF_IFACE_SYNC_SERIAL: /* set sync_serial_settings */
1566 
1567 		if(!capable(CAP_NET_ADMIN))
1568 			return -EPERM;
1569 		if (copy_from_user(&new_line, line, size))
1570 			return -EFAULT;
1571 
1572 		switch (new_line.clock_type)
1573 		{
1574 		case CLOCK_EXT:      flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_TXCPIN; break;
1575 		case CLOCK_TXFROMRX: flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_RXCPIN; break;
1576 		case CLOCK_INT:      flags = HDLC_FLAG_RXC_BRG    | HDLC_FLAG_TXC_BRG;    break;
1577 		case CLOCK_TXINT:    flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_BRG;    break;
1578 		case CLOCK_DEFAULT:  flags = info->params.flags &
1579 					     (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
1580 					      HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
1581 					      HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
1582 					      HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN); break;
1583 		default: return -EINVAL;
1584 		}
1585 
1586 		if (new_line.loopback != 0 && new_line.loopback != 1)
1587 			return -EINVAL;
1588 
1589 		info->params.flags &= ~(HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
1590 					HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
1591 					HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
1592 					HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN);
1593 		info->params.flags |= flags;
1594 
1595 		info->params.loopback = new_line.loopback;
1596 
1597 		if (flags & (HDLC_FLAG_RXC_BRG | HDLC_FLAG_TXC_BRG))
1598 			info->params.clock_speed = new_line.clock_rate;
1599 		else
1600 			info->params.clock_speed = 0;
1601 
1602 		/* if network interface up, reprogram hardware */
1603 		if (info->netcount)
1604 			program_hw(info);
1605 		return 0;
1606 
1607 	default:
1608 		return hdlc_ioctl(dev, ifs);
1609 	}
1610 }
1611 
1612 /**
1613  * hdlcdev_tx_timeout - called by network layer when transmit timeout is detected
1614  * @dev: pointer to network device structure
1615  * @txqueue: unused
1616  */
1617 static void hdlcdev_tx_timeout(struct net_device *dev, unsigned int txqueue)
1618 {
1619 	struct slgt_info *info = dev_to_port(dev);
1620 	unsigned long flags;
1621 
1622 	DBGINFO(("%s hdlcdev_tx_timeout\n", dev->name));
1623 
1624 	dev->stats.tx_errors++;
1625 	dev->stats.tx_aborted_errors++;
1626 
1627 	spin_lock_irqsave(&info->lock,flags);
1628 	tx_stop(info);
1629 	spin_unlock_irqrestore(&info->lock,flags);
1630 
1631 	netif_wake_queue(dev);
1632 }
1633 
1634 /**
1635  * hdlcdev_tx_done - called by device driver when transmit completes
1636  * @info: pointer to device instance information
1637  *
1638  * Reenable network layer transmit if stopped.
1639  */
1640 static void hdlcdev_tx_done(struct slgt_info *info)
1641 {
1642 	if (netif_queue_stopped(info->netdev))
1643 		netif_wake_queue(info->netdev);
1644 }
1645 
1646 /**
1647  * hdlcdev_rx - called by device driver when frame received
1648  * @info: pointer to device instance information
1649  * @buf:  pointer to buffer contianing frame data
1650  * @size: count of data bytes in buf
1651  *
1652  * Pass frame to network layer.
1653  */
1654 static void hdlcdev_rx(struct slgt_info *info, char *buf, int size)
1655 {
1656 	struct sk_buff *skb = dev_alloc_skb(size);
1657 	struct net_device *dev = info->netdev;
1658 
1659 	DBGINFO(("%s hdlcdev_rx\n", dev->name));
1660 
1661 	if (skb == NULL) {
1662 		DBGERR(("%s: can't alloc skb, drop packet\n", dev->name));
1663 		dev->stats.rx_dropped++;
1664 		return;
1665 	}
1666 
1667 	skb_put_data(skb, buf, size);
1668 
1669 	skb->protocol = hdlc_type_trans(skb, dev);
1670 
1671 	dev->stats.rx_packets++;
1672 	dev->stats.rx_bytes += size;
1673 
1674 	netif_rx(skb);
1675 }
1676 
1677 static const struct net_device_ops hdlcdev_ops = {
1678 	.ndo_open       = hdlcdev_open,
1679 	.ndo_stop       = hdlcdev_close,
1680 	.ndo_start_xmit = hdlc_start_xmit,
1681 	.ndo_siocwandev = hdlcdev_ioctl,
1682 	.ndo_tx_timeout = hdlcdev_tx_timeout,
1683 };
1684 
1685 /**
1686  * hdlcdev_init - called by device driver when adding device instance
1687  * @info: pointer to device instance information
1688  *
1689  * Do generic HDLC initialization.
1690  *
1691  * Return: 0 if success, otherwise error code
1692  */
1693 static int hdlcdev_init(struct slgt_info *info)
1694 {
1695 	int rc;
1696 	struct net_device *dev;
1697 	hdlc_device *hdlc;
1698 
1699 	/* allocate and initialize network and HDLC layer objects */
1700 
1701 	dev = alloc_hdlcdev(info);
1702 	if (!dev) {
1703 		printk(KERN_ERR "%s hdlc device alloc failure\n", info->device_name);
1704 		return -ENOMEM;
1705 	}
1706 
1707 	/* for network layer reporting purposes only */
1708 	dev->mem_start = info->phys_reg_addr;
1709 	dev->mem_end   = info->phys_reg_addr + SLGT_REG_SIZE - 1;
1710 	dev->irq       = info->irq_level;
1711 
1712 	/* network layer callbacks and settings */
1713 	dev->netdev_ops	    = &hdlcdev_ops;
1714 	dev->watchdog_timeo = 10 * HZ;
1715 	dev->tx_queue_len   = 50;
1716 
1717 	/* generic HDLC layer callbacks and settings */
1718 	hdlc         = dev_to_hdlc(dev);
1719 	hdlc->attach = hdlcdev_attach;
1720 	hdlc->xmit   = hdlcdev_xmit;
1721 
1722 	/* register objects with HDLC layer */
1723 	rc = register_hdlc_device(dev);
1724 	if (rc) {
1725 		printk(KERN_WARNING "%s:unable to register hdlc device\n",__FILE__);
1726 		free_netdev(dev);
1727 		return rc;
1728 	}
1729 
1730 	info->netdev = dev;
1731 	return 0;
1732 }
1733 
1734 /**
1735  * hdlcdev_exit - called by device driver when removing device instance
1736  * @info: pointer to device instance information
1737  *
1738  * Do generic HDLC cleanup.
1739  */
1740 static void hdlcdev_exit(struct slgt_info *info)
1741 {
1742 	if (!info->netdev)
1743 		return;
1744 	unregister_hdlc_device(info->netdev);
1745 	free_netdev(info->netdev);
1746 	info->netdev = NULL;
1747 }
1748 
1749 #endif /* ifdef CONFIG_HDLC */
1750 
1751 /*
1752  * get async data from rx DMA buffers
1753  */
1754 static void rx_async(struct slgt_info *info)
1755 {
1756  	struct mgsl_icount *icount = &info->icount;
1757 	unsigned int start, end;
1758 	unsigned char *p;
1759 	unsigned char status;
1760 	struct slgt_desc *bufs = info->rbufs;
1761 	int i, count;
1762 	int chars = 0;
1763 	int stat;
1764 	unsigned char ch;
1765 
1766 	start = end = info->rbuf_current;
1767 
1768 	while(desc_complete(bufs[end])) {
1769 		count = desc_count(bufs[end]) - info->rbuf_index;
1770 		p     = bufs[end].buf + info->rbuf_index;
1771 
1772 		DBGISR(("%s rx_async count=%d\n", info->device_name, count));
1773 		DBGDATA(info, p, count, "rx");
1774 
1775 		for(i=0 ; i < count; i+=2, p+=2) {
1776 			ch = *p;
1777 			icount->rx++;
1778 
1779 			stat = 0;
1780 
1781 			status = *(p + 1) & (BIT1 + BIT0);
1782 			if (status) {
1783 				if (status & BIT1)
1784 					icount->parity++;
1785 				else if (status & BIT0)
1786 					icount->frame++;
1787 				/* discard char if tty control flags say so */
1788 				if (status & info->ignore_status_mask)
1789 					continue;
1790 				if (status & BIT1)
1791 					stat = TTY_PARITY;
1792 				else if (status & BIT0)
1793 					stat = TTY_FRAME;
1794 			}
1795 			tty_insert_flip_char(&info->port, ch, stat);
1796 			chars++;
1797 		}
1798 
1799 		if (i < count) {
1800 			/* receive buffer not completed */
1801 			info->rbuf_index += i;
1802 			mod_timer(&info->rx_timer, jiffies + 1);
1803 			break;
1804 		}
1805 
1806 		info->rbuf_index = 0;
1807 		free_rbufs(info, end, end);
1808 
1809 		if (++end == info->rbuf_count)
1810 			end = 0;
1811 
1812 		/* if entire list searched then no frame available */
1813 		if (end == start)
1814 			break;
1815 	}
1816 
1817 	if (chars)
1818 		tty_flip_buffer_push(&info->port);
1819 }
1820 
1821 /*
1822  * return next bottom half action to perform
1823  */
1824 static int bh_action(struct slgt_info *info)
1825 {
1826 	unsigned long flags;
1827 	int rc;
1828 
1829 	spin_lock_irqsave(&info->lock,flags);
1830 
1831 	if (info->pending_bh & BH_RECEIVE) {
1832 		info->pending_bh &= ~BH_RECEIVE;
1833 		rc = BH_RECEIVE;
1834 	} else if (info->pending_bh & BH_TRANSMIT) {
1835 		info->pending_bh &= ~BH_TRANSMIT;
1836 		rc = BH_TRANSMIT;
1837 	} else if (info->pending_bh & BH_STATUS) {
1838 		info->pending_bh &= ~BH_STATUS;
1839 		rc = BH_STATUS;
1840 	} else {
1841 		/* Mark BH routine as complete */
1842 		info->bh_running = false;
1843 		info->bh_requested = false;
1844 		rc = 0;
1845 	}
1846 
1847 	spin_unlock_irqrestore(&info->lock,flags);
1848 
1849 	return rc;
1850 }
1851 
1852 /*
1853  * perform bottom half processing
1854  */
1855 static void bh_handler(struct work_struct *work)
1856 {
1857 	struct slgt_info *info = container_of(work, struct slgt_info, task);
1858 	int action;
1859 
1860 	info->bh_running = true;
1861 
1862 	while((action = bh_action(info))) {
1863 		switch (action) {
1864 		case BH_RECEIVE:
1865 			DBGBH(("%s bh receive\n", info->device_name));
1866 			switch(info->params.mode) {
1867 			case MGSL_MODE_ASYNC:
1868 				rx_async(info);
1869 				break;
1870 			case MGSL_MODE_HDLC:
1871 				while(rx_get_frame(info));
1872 				break;
1873 			case MGSL_MODE_RAW:
1874 			case MGSL_MODE_MONOSYNC:
1875 			case MGSL_MODE_BISYNC:
1876 			case MGSL_MODE_XSYNC:
1877 				while(rx_get_buf(info));
1878 				break;
1879 			}
1880 			/* restart receiver if rx DMA buffers exhausted */
1881 			if (info->rx_restart)
1882 				rx_start(info);
1883 			break;
1884 		case BH_TRANSMIT:
1885 			bh_transmit(info);
1886 			break;
1887 		case BH_STATUS:
1888 			DBGBH(("%s bh status\n", info->device_name));
1889 			info->ri_chkcount = 0;
1890 			info->dsr_chkcount = 0;
1891 			info->dcd_chkcount = 0;
1892 			info->cts_chkcount = 0;
1893 			break;
1894 		default:
1895 			DBGBH(("%s unknown action\n", info->device_name));
1896 			break;
1897 		}
1898 	}
1899 	DBGBH(("%s bh_handler exit\n", info->device_name));
1900 }
1901 
1902 static void bh_transmit(struct slgt_info *info)
1903 {
1904 	struct tty_struct *tty = info->port.tty;
1905 
1906 	DBGBH(("%s bh_transmit\n", info->device_name));
1907 	if (tty)
1908 		tty_wakeup(tty);
1909 }
1910 
1911 static void dsr_change(struct slgt_info *info, unsigned short status)
1912 {
1913 	if (status & BIT3) {
1914 		info->signals |= SerialSignal_DSR;
1915 		info->input_signal_events.dsr_up++;
1916 	} else {
1917 		info->signals &= ~SerialSignal_DSR;
1918 		info->input_signal_events.dsr_down++;
1919 	}
1920 	DBGISR(("dsr_change %s signals=%04X\n", info->device_name, info->signals));
1921 	if ((info->dsr_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
1922 		slgt_irq_off(info, IRQ_DSR);
1923 		return;
1924 	}
1925 	info->icount.dsr++;
1926 	wake_up_interruptible(&info->status_event_wait_q);
1927 	wake_up_interruptible(&info->event_wait_q);
1928 	info->pending_bh |= BH_STATUS;
1929 }
1930 
1931 static void cts_change(struct slgt_info *info, unsigned short status)
1932 {
1933 	if (status & BIT2) {
1934 		info->signals |= SerialSignal_CTS;
1935 		info->input_signal_events.cts_up++;
1936 	} else {
1937 		info->signals &= ~SerialSignal_CTS;
1938 		info->input_signal_events.cts_down++;
1939 	}
1940 	DBGISR(("cts_change %s signals=%04X\n", info->device_name, info->signals));
1941 	if ((info->cts_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
1942 		slgt_irq_off(info, IRQ_CTS);
1943 		return;
1944 	}
1945 	info->icount.cts++;
1946 	wake_up_interruptible(&info->status_event_wait_q);
1947 	wake_up_interruptible(&info->event_wait_q);
1948 	info->pending_bh |= BH_STATUS;
1949 
1950 	if (tty_port_cts_enabled(&info->port)) {
1951 		if (info->port.tty) {
1952 			if (info->port.tty->hw_stopped) {
1953 				if (info->signals & SerialSignal_CTS) {
1954 					info->port.tty->hw_stopped = false;
1955 					info->pending_bh |= BH_TRANSMIT;
1956 					return;
1957 				}
1958 			} else {
1959 				if (!(info->signals & SerialSignal_CTS))
1960 					info->port.tty->hw_stopped = true;
1961 			}
1962 		}
1963 	}
1964 }
1965 
1966 static void dcd_change(struct slgt_info *info, unsigned short status)
1967 {
1968 	if (status & BIT1) {
1969 		info->signals |= SerialSignal_DCD;
1970 		info->input_signal_events.dcd_up++;
1971 	} else {
1972 		info->signals &= ~SerialSignal_DCD;
1973 		info->input_signal_events.dcd_down++;
1974 	}
1975 	DBGISR(("dcd_change %s signals=%04X\n", info->device_name, info->signals));
1976 	if ((info->dcd_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
1977 		slgt_irq_off(info, IRQ_DCD);
1978 		return;
1979 	}
1980 	info->icount.dcd++;
1981 #if SYNCLINK_GENERIC_HDLC
1982 	if (info->netcount) {
1983 		if (info->signals & SerialSignal_DCD)
1984 			netif_carrier_on(info->netdev);
1985 		else
1986 			netif_carrier_off(info->netdev);
1987 	}
1988 #endif
1989 	wake_up_interruptible(&info->status_event_wait_q);
1990 	wake_up_interruptible(&info->event_wait_q);
1991 	info->pending_bh |= BH_STATUS;
1992 
1993 	if (tty_port_check_carrier(&info->port)) {
1994 		if (info->signals & SerialSignal_DCD)
1995 			wake_up_interruptible(&info->port.open_wait);
1996 		else {
1997 			if (info->port.tty)
1998 				tty_hangup(info->port.tty);
1999 		}
2000 	}
2001 }
2002 
2003 static void ri_change(struct slgt_info *info, unsigned short status)
2004 {
2005 	if (status & BIT0) {
2006 		info->signals |= SerialSignal_RI;
2007 		info->input_signal_events.ri_up++;
2008 	} else {
2009 		info->signals &= ~SerialSignal_RI;
2010 		info->input_signal_events.ri_down++;
2011 	}
2012 	DBGISR(("ri_change %s signals=%04X\n", info->device_name, info->signals));
2013 	if ((info->ri_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
2014 		slgt_irq_off(info, IRQ_RI);
2015 		return;
2016 	}
2017 	info->icount.rng++;
2018 	wake_up_interruptible(&info->status_event_wait_q);
2019 	wake_up_interruptible(&info->event_wait_q);
2020 	info->pending_bh |= BH_STATUS;
2021 }
2022 
2023 static void isr_rxdata(struct slgt_info *info)
2024 {
2025 	unsigned int count = info->rbuf_fill_count;
2026 	unsigned int i = info->rbuf_fill_index;
2027 	unsigned short reg;
2028 
2029 	while (rd_reg16(info, SSR) & IRQ_RXDATA) {
2030 		reg = rd_reg16(info, RDR);
2031 		DBGISR(("isr_rxdata %s RDR=%04X\n", info->device_name, reg));
2032 		if (desc_complete(info->rbufs[i])) {
2033 			/* all buffers full */
2034 			rx_stop(info);
2035 			info->rx_restart = true;
2036 			continue;
2037 		}
2038 		info->rbufs[i].buf[count++] = (unsigned char)reg;
2039 		/* async mode saves status byte to buffer for each data byte */
2040 		if (info->params.mode == MGSL_MODE_ASYNC)
2041 			info->rbufs[i].buf[count++] = (unsigned char)(reg >> 8);
2042 		if (count == info->rbuf_fill_level || (reg & BIT10)) {
2043 			/* buffer full or end of frame */
2044 			set_desc_count(info->rbufs[i], count);
2045 			set_desc_status(info->rbufs[i], BIT15 | (reg >> 8));
2046 			info->rbuf_fill_count = count = 0;
2047 			if (++i == info->rbuf_count)
2048 				i = 0;
2049 			info->pending_bh |= BH_RECEIVE;
2050 		}
2051 	}
2052 
2053 	info->rbuf_fill_index = i;
2054 	info->rbuf_fill_count = count;
2055 }
2056 
2057 static void isr_serial(struct slgt_info *info)
2058 {
2059 	unsigned short status = rd_reg16(info, SSR);
2060 
2061 	DBGISR(("%s isr_serial status=%04X\n", info->device_name, status));
2062 
2063 	wr_reg16(info, SSR, status); /* clear pending */
2064 
2065 	info->irq_occurred = true;
2066 
2067 	if (info->params.mode == MGSL_MODE_ASYNC) {
2068 		if (status & IRQ_TXIDLE) {
2069 			if (info->tx_active)
2070 				isr_txeom(info, status);
2071 		}
2072 		if (info->rx_pio && (status & IRQ_RXDATA))
2073 			isr_rxdata(info);
2074 		if ((status & IRQ_RXBREAK) && (status & RXBREAK)) {
2075 			info->icount.brk++;
2076 			/* process break detection if tty control allows */
2077 			if (info->port.tty) {
2078 				if (!(status & info->ignore_status_mask)) {
2079 					if (info->read_status_mask & MASK_BREAK) {
2080 						tty_insert_flip_char(&info->port, 0, TTY_BREAK);
2081 						if (info->port.flags & ASYNC_SAK)
2082 							do_SAK(info->port.tty);
2083 					}
2084 				}
2085 			}
2086 		}
2087 	} else {
2088 		if (status & (IRQ_TXIDLE + IRQ_TXUNDER))
2089 			isr_txeom(info, status);
2090 		if (info->rx_pio && (status & IRQ_RXDATA))
2091 			isr_rxdata(info);
2092 		if (status & IRQ_RXIDLE) {
2093 			if (status & RXIDLE)
2094 				info->icount.rxidle++;
2095 			else
2096 				info->icount.exithunt++;
2097 			wake_up_interruptible(&info->event_wait_q);
2098 		}
2099 
2100 		if (status & IRQ_RXOVER)
2101 			rx_start(info);
2102 	}
2103 
2104 	if (status & IRQ_DSR)
2105 		dsr_change(info, status);
2106 	if (status & IRQ_CTS)
2107 		cts_change(info, status);
2108 	if (status & IRQ_DCD)
2109 		dcd_change(info, status);
2110 	if (status & IRQ_RI)
2111 		ri_change(info, status);
2112 }
2113 
2114 static void isr_rdma(struct slgt_info *info)
2115 {
2116 	unsigned int status = rd_reg32(info, RDCSR);
2117 
2118 	DBGISR(("%s isr_rdma status=%08x\n", info->device_name, status));
2119 
2120 	/* RDCSR (rx DMA control/status)
2121 	 *
2122 	 * 31..07  reserved
2123 	 * 06      save status byte to DMA buffer
2124 	 * 05      error
2125 	 * 04      eol (end of list)
2126 	 * 03      eob (end of buffer)
2127 	 * 02      IRQ enable
2128 	 * 01      reset
2129 	 * 00      enable
2130 	 */
2131 	wr_reg32(info, RDCSR, status);	/* clear pending */
2132 
2133 	if (status & (BIT5 + BIT4)) {
2134 		DBGISR(("%s isr_rdma rx_restart=1\n", info->device_name));
2135 		info->rx_restart = true;
2136 	}
2137 	info->pending_bh |= BH_RECEIVE;
2138 }
2139 
2140 static void isr_tdma(struct slgt_info *info)
2141 {
2142 	unsigned int status = rd_reg32(info, TDCSR);
2143 
2144 	DBGISR(("%s isr_tdma status=%08x\n", info->device_name, status));
2145 
2146 	/* TDCSR (tx DMA control/status)
2147 	 *
2148 	 * 31..06  reserved
2149 	 * 05      error
2150 	 * 04      eol (end of list)
2151 	 * 03      eob (end of buffer)
2152 	 * 02      IRQ enable
2153 	 * 01      reset
2154 	 * 00      enable
2155 	 */
2156 	wr_reg32(info, TDCSR, status);	/* clear pending */
2157 
2158 	if (status & (BIT5 + BIT4 + BIT3)) {
2159 		// another transmit buffer has completed
2160 		// run bottom half to get more send data from user
2161 		info->pending_bh |= BH_TRANSMIT;
2162 	}
2163 }
2164 
2165 /*
2166  * return true if there are unsent tx DMA buffers, otherwise false
2167  *
2168  * if there are unsent buffers then info->tbuf_start
2169  * is set to index of first unsent buffer
2170  */
2171 static bool unsent_tbufs(struct slgt_info *info)
2172 {
2173 	unsigned int i = info->tbuf_current;
2174 	bool rc = false;
2175 
2176 	/*
2177 	 * search backwards from last loaded buffer (precedes tbuf_current)
2178 	 * for first unsent buffer (desc_count > 0)
2179 	 */
2180 
2181 	do {
2182 		if (i)
2183 			i--;
2184 		else
2185 			i = info->tbuf_count - 1;
2186 		if (!desc_count(info->tbufs[i]))
2187 			break;
2188 		info->tbuf_start = i;
2189 		rc = true;
2190 	} while (i != info->tbuf_current);
2191 
2192 	return rc;
2193 }
2194 
2195 static void isr_txeom(struct slgt_info *info, unsigned short status)
2196 {
2197 	DBGISR(("%s txeom status=%04x\n", info->device_name, status));
2198 
2199 	slgt_irq_off(info, IRQ_TXDATA + IRQ_TXIDLE + IRQ_TXUNDER);
2200 	tdma_reset(info);
2201 	if (status & IRQ_TXUNDER) {
2202 		unsigned short val = rd_reg16(info, TCR);
2203 		wr_reg16(info, TCR, (unsigned short)(val | BIT2)); /* set reset bit */
2204 		wr_reg16(info, TCR, val); /* clear reset bit */
2205 	}
2206 
2207 	if (info->tx_active) {
2208 		if (info->params.mode != MGSL_MODE_ASYNC) {
2209 			if (status & IRQ_TXUNDER)
2210 				info->icount.txunder++;
2211 			else if (status & IRQ_TXIDLE)
2212 				info->icount.txok++;
2213 		}
2214 
2215 		if (unsent_tbufs(info)) {
2216 			tx_start(info);
2217 			update_tx_timer(info);
2218 			return;
2219 		}
2220 		info->tx_active = false;
2221 
2222 		del_timer(&info->tx_timer);
2223 
2224 		if (info->params.mode != MGSL_MODE_ASYNC && info->drop_rts_on_tx_done) {
2225 			info->signals &= ~SerialSignal_RTS;
2226 			info->drop_rts_on_tx_done = false;
2227 			set_gtsignals(info);
2228 		}
2229 
2230 #if SYNCLINK_GENERIC_HDLC
2231 		if (info->netcount)
2232 			hdlcdev_tx_done(info);
2233 		else
2234 #endif
2235 		{
2236 			if (info->port.tty && (info->port.tty->flow.stopped || info->port.tty->hw_stopped)) {
2237 				tx_stop(info);
2238 				return;
2239 			}
2240 			info->pending_bh |= BH_TRANSMIT;
2241 		}
2242 	}
2243 }
2244 
2245 static void isr_gpio(struct slgt_info *info, unsigned int changed, unsigned int state)
2246 {
2247 	struct cond_wait *w, *prev;
2248 
2249 	/* wake processes waiting for specific transitions */
2250 	for (w = info->gpio_wait_q, prev = NULL ; w != NULL ; w = w->next) {
2251 		if (w->data & changed) {
2252 			w->data = state;
2253 			wake_up_interruptible(&w->q);
2254 			if (prev != NULL)
2255 				prev->next = w->next;
2256 			else
2257 				info->gpio_wait_q = w->next;
2258 		} else
2259 			prev = w;
2260 	}
2261 }
2262 
2263 /* interrupt service routine
2264  *
2265  * 	irq	interrupt number
2266  * 	dev_id	device ID supplied during interrupt registration
2267  */
2268 static irqreturn_t slgt_interrupt(int dummy, void *dev_id)
2269 {
2270 	struct slgt_info *info = dev_id;
2271 	unsigned int gsr;
2272 	unsigned int i;
2273 
2274 	DBGISR(("slgt_interrupt irq=%d entry\n", info->irq_level));
2275 
2276 	while((gsr = rd_reg32(info, GSR) & 0xffffff00)) {
2277 		DBGISR(("%s gsr=%08x\n", info->device_name, gsr));
2278 		info->irq_occurred = true;
2279 		for(i=0; i < info->port_count ; i++) {
2280 			if (info->port_array[i] == NULL)
2281 				continue;
2282 			spin_lock(&info->port_array[i]->lock);
2283 			if (gsr & (BIT8 << i))
2284 				isr_serial(info->port_array[i]);
2285 			if (gsr & (BIT16 << (i*2)))
2286 				isr_rdma(info->port_array[i]);
2287 			if (gsr & (BIT17 << (i*2)))
2288 				isr_tdma(info->port_array[i]);
2289 			spin_unlock(&info->port_array[i]->lock);
2290 		}
2291 	}
2292 
2293 	if (info->gpio_present) {
2294 		unsigned int state;
2295 		unsigned int changed;
2296 		spin_lock(&info->lock);
2297 		while ((changed = rd_reg32(info, IOSR)) != 0) {
2298 			DBGISR(("%s iosr=%08x\n", info->device_name, changed));
2299 			/* read latched state of GPIO signals */
2300 			state = rd_reg32(info, IOVR);
2301 			/* clear pending GPIO interrupt bits */
2302 			wr_reg32(info, IOSR, changed);
2303 			for (i=0 ; i < info->port_count ; i++) {
2304 				if (info->port_array[i] != NULL)
2305 					isr_gpio(info->port_array[i], changed, state);
2306 			}
2307 		}
2308 		spin_unlock(&info->lock);
2309 	}
2310 
2311 	for(i=0; i < info->port_count ; i++) {
2312 		struct slgt_info *port = info->port_array[i];
2313 		if (port == NULL)
2314 			continue;
2315 		spin_lock(&port->lock);
2316 		if ((port->port.count || port->netcount) &&
2317 		    port->pending_bh && !port->bh_running &&
2318 		    !port->bh_requested) {
2319 			DBGISR(("%s bh queued\n", port->device_name));
2320 			schedule_work(&port->task);
2321 			port->bh_requested = true;
2322 		}
2323 		spin_unlock(&port->lock);
2324 	}
2325 
2326 	DBGISR(("slgt_interrupt irq=%d exit\n", info->irq_level));
2327 	return IRQ_HANDLED;
2328 }
2329 
2330 static int startup(struct slgt_info *info)
2331 {
2332 	DBGINFO(("%s startup\n", info->device_name));
2333 
2334 	if (tty_port_initialized(&info->port))
2335 		return 0;
2336 
2337 	if (!info->tx_buf) {
2338 		info->tx_buf = kmalloc(info->max_frame_size, GFP_KERNEL);
2339 		if (!info->tx_buf) {
2340 			DBGERR(("%s can't allocate tx buffer\n", info->device_name));
2341 			return -ENOMEM;
2342 		}
2343 	}
2344 
2345 	info->pending_bh = 0;
2346 
2347 	memset(&info->icount, 0, sizeof(info->icount));
2348 
2349 	/* program hardware for current parameters */
2350 	change_params(info);
2351 
2352 	if (info->port.tty)
2353 		clear_bit(TTY_IO_ERROR, &info->port.tty->flags);
2354 
2355 	tty_port_set_initialized(&info->port, true);
2356 
2357 	return 0;
2358 }
2359 
2360 /*
2361  *  called by close() and hangup() to shutdown hardware
2362  */
2363 static void shutdown(struct slgt_info *info)
2364 {
2365 	unsigned long flags;
2366 
2367 	if (!tty_port_initialized(&info->port))
2368 		return;
2369 
2370 	DBGINFO(("%s shutdown\n", info->device_name));
2371 
2372 	/* clear status wait queue because status changes */
2373 	/* can't happen after shutting down the hardware */
2374 	wake_up_interruptible(&info->status_event_wait_q);
2375 	wake_up_interruptible(&info->event_wait_q);
2376 
2377 	del_timer_sync(&info->tx_timer);
2378 	del_timer_sync(&info->rx_timer);
2379 
2380 	kfree(info->tx_buf);
2381 	info->tx_buf = NULL;
2382 
2383 	spin_lock_irqsave(&info->lock,flags);
2384 
2385 	tx_stop(info);
2386 	rx_stop(info);
2387 
2388 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
2389 
2390  	if (!info->port.tty || info->port.tty->termios.c_cflag & HUPCL) {
2391 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
2392 		set_gtsignals(info);
2393 	}
2394 
2395 	flush_cond_wait(&info->gpio_wait_q);
2396 
2397 	spin_unlock_irqrestore(&info->lock,flags);
2398 
2399 	if (info->port.tty)
2400 		set_bit(TTY_IO_ERROR, &info->port.tty->flags);
2401 
2402 	tty_port_set_initialized(&info->port, false);
2403 }
2404 
2405 static void program_hw(struct slgt_info *info)
2406 {
2407 	unsigned long flags;
2408 
2409 	spin_lock_irqsave(&info->lock,flags);
2410 
2411 	rx_stop(info);
2412 	tx_stop(info);
2413 
2414 	if (info->params.mode != MGSL_MODE_ASYNC ||
2415 	    info->netcount)
2416 		sync_mode(info);
2417 	else
2418 		async_mode(info);
2419 
2420 	set_gtsignals(info);
2421 
2422 	info->dcd_chkcount = 0;
2423 	info->cts_chkcount = 0;
2424 	info->ri_chkcount = 0;
2425 	info->dsr_chkcount = 0;
2426 
2427 	slgt_irq_on(info, IRQ_DCD | IRQ_CTS | IRQ_DSR | IRQ_RI);
2428 	get_gtsignals(info);
2429 
2430 	if (info->netcount ||
2431 	    (info->port.tty && info->port.tty->termios.c_cflag & CREAD))
2432 		rx_start(info);
2433 
2434 	spin_unlock_irqrestore(&info->lock,flags);
2435 }
2436 
2437 /*
2438  * reconfigure adapter based on new parameters
2439  */
2440 static void change_params(struct slgt_info *info)
2441 {
2442 	unsigned cflag;
2443 	int bits_per_char;
2444 
2445 	if (!info->port.tty)
2446 		return;
2447 	DBGINFO(("%s change_params\n", info->device_name));
2448 
2449 	cflag = info->port.tty->termios.c_cflag;
2450 
2451 	/* if B0 rate (hangup) specified then negate RTS and DTR */
2452 	/* otherwise assert RTS and DTR */
2453  	if (cflag & CBAUD)
2454 		info->signals |= SerialSignal_RTS | SerialSignal_DTR;
2455 	else
2456 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
2457 
2458 	/* byte size and parity */
2459 
2460 	info->params.data_bits = tty_get_char_size(cflag);
2461 	info->params.stop_bits = (cflag & CSTOPB) ? 2 : 1;
2462 
2463 	if (cflag & PARENB)
2464 		info->params.parity = (cflag & PARODD) ? ASYNC_PARITY_ODD : ASYNC_PARITY_EVEN;
2465 	else
2466 		info->params.parity = ASYNC_PARITY_NONE;
2467 
2468 	/* calculate number of jiffies to transmit a full
2469 	 * FIFO (32 bytes) at specified data rate
2470 	 */
2471 	bits_per_char = info->params.data_bits +
2472 			info->params.stop_bits + 1;
2473 
2474 	info->params.data_rate = tty_get_baud_rate(info->port.tty);
2475 
2476 	if (info->params.data_rate) {
2477 		info->timeout = (32*HZ*bits_per_char) /
2478 				info->params.data_rate;
2479 	}
2480 	info->timeout += HZ/50;		/* Add .02 seconds of slop */
2481 
2482 	tty_port_set_cts_flow(&info->port, cflag & CRTSCTS);
2483 	tty_port_set_check_carrier(&info->port, ~cflag & CLOCAL);
2484 
2485 	/* process tty input control flags */
2486 
2487 	info->read_status_mask = IRQ_RXOVER;
2488 	if (I_INPCK(info->port.tty))
2489 		info->read_status_mask |= MASK_PARITY | MASK_FRAMING;
2490 	if (I_BRKINT(info->port.tty) || I_PARMRK(info->port.tty))
2491 		info->read_status_mask |= MASK_BREAK;
2492 	if (I_IGNPAR(info->port.tty))
2493 		info->ignore_status_mask |= MASK_PARITY | MASK_FRAMING;
2494 	if (I_IGNBRK(info->port.tty)) {
2495 		info->ignore_status_mask |= MASK_BREAK;
2496 		/* If ignoring parity and break indicators, ignore
2497 		 * overruns too.  (For real raw support).
2498 		 */
2499 		if (I_IGNPAR(info->port.tty))
2500 			info->ignore_status_mask |= MASK_OVERRUN;
2501 	}
2502 
2503 	program_hw(info);
2504 }
2505 
2506 static int get_stats(struct slgt_info *info, struct mgsl_icount __user *user_icount)
2507 {
2508 	DBGINFO(("%s get_stats\n",  info->device_name));
2509 	if (!user_icount) {
2510 		memset(&info->icount, 0, sizeof(info->icount));
2511 	} else {
2512 		if (copy_to_user(user_icount, &info->icount, sizeof(struct mgsl_icount)))
2513 			return -EFAULT;
2514 	}
2515 	return 0;
2516 }
2517 
2518 static int get_params(struct slgt_info *info, MGSL_PARAMS __user *user_params)
2519 {
2520 	DBGINFO(("%s get_params\n", info->device_name));
2521 	if (copy_to_user(user_params, &info->params, sizeof(MGSL_PARAMS)))
2522 		return -EFAULT;
2523 	return 0;
2524 }
2525 
2526 static int set_params(struct slgt_info *info, MGSL_PARAMS __user *new_params)
2527 {
2528  	unsigned long flags;
2529 	MGSL_PARAMS tmp_params;
2530 
2531 	DBGINFO(("%s set_params\n", info->device_name));
2532 	if (copy_from_user(&tmp_params, new_params, sizeof(MGSL_PARAMS)))
2533 		return -EFAULT;
2534 
2535 	spin_lock_irqsave(&info->lock, flags);
2536 	if (tmp_params.mode == MGSL_MODE_BASE_CLOCK)
2537 		info->base_clock = tmp_params.clock_speed;
2538 	else
2539 		memcpy(&info->params, &tmp_params, sizeof(MGSL_PARAMS));
2540 	spin_unlock_irqrestore(&info->lock, flags);
2541 
2542 	program_hw(info);
2543 
2544 	return 0;
2545 }
2546 
2547 static int get_txidle(struct slgt_info *info, int __user *idle_mode)
2548 {
2549 	DBGINFO(("%s get_txidle=%d\n", info->device_name, info->idle_mode));
2550 	if (put_user(info->idle_mode, idle_mode))
2551 		return -EFAULT;
2552 	return 0;
2553 }
2554 
2555 static int set_txidle(struct slgt_info *info, int idle_mode)
2556 {
2557  	unsigned long flags;
2558 	DBGINFO(("%s set_txidle(%d)\n", info->device_name, idle_mode));
2559 	spin_lock_irqsave(&info->lock,flags);
2560 	info->idle_mode = idle_mode;
2561 	if (info->params.mode != MGSL_MODE_ASYNC)
2562 		tx_set_idle(info);
2563 	spin_unlock_irqrestore(&info->lock,flags);
2564 	return 0;
2565 }
2566 
2567 static int tx_enable(struct slgt_info *info, int enable)
2568 {
2569  	unsigned long flags;
2570 	DBGINFO(("%s tx_enable(%d)\n", info->device_name, enable));
2571 	spin_lock_irqsave(&info->lock,flags);
2572 	if (enable) {
2573 		if (!info->tx_enabled)
2574 			tx_start(info);
2575 	} else {
2576 		if (info->tx_enabled)
2577 			tx_stop(info);
2578 	}
2579 	spin_unlock_irqrestore(&info->lock,flags);
2580 	return 0;
2581 }
2582 
2583 /*
2584  * abort transmit HDLC frame
2585  */
2586 static int tx_abort(struct slgt_info *info)
2587 {
2588  	unsigned long flags;
2589 	DBGINFO(("%s tx_abort\n", info->device_name));
2590 	spin_lock_irqsave(&info->lock,flags);
2591 	tdma_reset(info);
2592 	spin_unlock_irqrestore(&info->lock,flags);
2593 	return 0;
2594 }
2595 
2596 static int rx_enable(struct slgt_info *info, int enable)
2597 {
2598  	unsigned long flags;
2599 	unsigned int rbuf_fill_level;
2600 	DBGINFO(("%s rx_enable(%08x)\n", info->device_name, enable));
2601 	spin_lock_irqsave(&info->lock,flags);
2602 	/*
2603 	 * enable[31..16] = receive DMA buffer fill level
2604 	 * 0 = noop (leave fill level unchanged)
2605 	 * fill level must be multiple of 4 and <= buffer size
2606 	 */
2607 	rbuf_fill_level = ((unsigned int)enable) >> 16;
2608 	if (rbuf_fill_level) {
2609 		if ((rbuf_fill_level > DMABUFSIZE) || (rbuf_fill_level % 4)) {
2610 			spin_unlock_irqrestore(&info->lock, flags);
2611 			return -EINVAL;
2612 		}
2613 		info->rbuf_fill_level = rbuf_fill_level;
2614 		if (rbuf_fill_level < 128)
2615 			info->rx_pio = 1; /* PIO mode */
2616 		else
2617 			info->rx_pio = 0; /* DMA mode */
2618 		rx_stop(info); /* restart receiver to use new fill level */
2619 	}
2620 
2621 	/*
2622 	 * enable[1..0] = receiver enable command
2623 	 * 0 = disable
2624 	 * 1 = enable
2625 	 * 2 = enable or force hunt mode if already enabled
2626 	 */
2627 	enable &= 3;
2628 	if (enable) {
2629 		if (!info->rx_enabled)
2630 			rx_start(info);
2631 		else if (enable == 2) {
2632 			/* force hunt mode (write 1 to RCR[3]) */
2633 			wr_reg16(info, RCR, rd_reg16(info, RCR) | BIT3);
2634 		}
2635 	} else {
2636 		if (info->rx_enabled)
2637 			rx_stop(info);
2638 	}
2639 	spin_unlock_irqrestore(&info->lock,flags);
2640 	return 0;
2641 }
2642 
2643 /*
2644  *  wait for specified event to occur
2645  */
2646 static int wait_mgsl_event(struct slgt_info *info, int __user *mask_ptr)
2647 {
2648  	unsigned long flags;
2649 	int s;
2650 	int rc=0;
2651 	struct mgsl_icount cprev, cnow;
2652 	int events;
2653 	int mask;
2654 	struct	_input_signal_events oldsigs, newsigs;
2655 	DECLARE_WAITQUEUE(wait, current);
2656 
2657 	if (get_user(mask, mask_ptr))
2658 		return -EFAULT;
2659 
2660 	DBGINFO(("%s wait_mgsl_event(%d)\n", info->device_name, mask));
2661 
2662 	spin_lock_irqsave(&info->lock,flags);
2663 
2664 	/* return immediately if state matches requested events */
2665 	get_gtsignals(info);
2666 	s = info->signals;
2667 
2668 	events = mask &
2669 		( ((s & SerialSignal_DSR) ? MgslEvent_DsrActive:MgslEvent_DsrInactive) +
2670  		  ((s & SerialSignal_DCD) ? MgslEvent_DcdActive:MgslEvent_DcdInactive) +
2671 		  ((s & SerialSignal_CTS) ? MgslEvent_CtsActive:MgslEvent_CtsInactive) +
2672 		  ((s & SerialSignal_RI)  ? MgslEvent_RiActive :MgslEvent_RiInactive) );
2673 	if (events) {
2674 		spin_unlock_irqrestore(&info->lock,flags);
2675 		goto exit;
2676 	}
2677 
2678 	/* save current irq counts */
2679 	cprev = info->icount;
2680 	oldsigs = info->input_signal_events;
2681 
2682 	/* enable hunt and idle irqs if needed */
2683 	if (mask & (MgslEvent_ExitHuntMode+MgslEvent_IdleReceived)) {
2684 		unsigned short val = rd_reg16(info, SCR);
2685 		if (!(val & IRQ_RXIDLE))
2686 			wr_reg16(info, SCR, (unsigned short)(val | IRQ_RXIDLE));
2687 	}
2688 
2689 	set_current_state(TASK_INTERRUPTIBLE);
2690 	add_wait_queue(&info->event_wait_q, &wait);
2691 
2692 	spin_unlock_irqrestore(&info->lock,flags);
2693 
2694 	for(;;) {
2695 		schedule();
2696 		if (signal_pending(current)) {
2697 			rc = -ERESTARTSYS;
2698 			break;
2699 		}
2700 
2701 		/* get current irq counts */
2702 		spin_lock_irqsave(&info->lock,flags);
2703 		cnow = info->icount;
2704 		newsigs = info->input_signal_events;
2705 		set_current_state(TASK_INTERRUPTIBLE);
2706 		spin_unlock_irqrestore(&info->lock,flags);
2707 
2708 		/* if no change, wait aborted for some reason */
2709 		if (newsigs.dsr_up   == oldsigs.dsr_up   &&
2710 		    newsigs.dsr_down == oldsigs.dsr_down &&
2711 		    newsigs.dcd_up   == oldsigs.dcd_up   &&
2712 		    newsigs.dcd_down == oldsigs.dcd_down &&
2713 		    newsigs.cts_up   == oldsigs.cts_up   &&
2714 		    newsigs.cts_down == oldsigs.cts_down &&
2715 		    newsigs.ri_up    == oldsigs.ri_up    &&
2716 		    newsigs.ri_down  == oldsigs.ri_down  &&
2717 		    cnow.exithunt    == cprev.exithunt   &&
2718 		    cnow.rxidle      == cprev.rxidle) {
2719 			rc = -EIO;
2720 			break;
2721 		}
2722 
2723 		events = mask &
2724 			( (newsigs.dsr_up   != oldsigs.dsr_up   ? MgslEvent_DsrActive:0)   +
2725 			  (newsigs.dsr_down != oldsigs.dsr_down ? MgslEvent_DsrInactive:0) +
2726 			  (newsigs.dcd_up   != oldsigs.dcd_up   ? MgslEvent_DcdActive:0)   +
2727 			  (newsigs.dcd_down != oldsigs.dcd_down ? MgslEvent_DcdInactive:0) +
2728 			  (newsigs.cts_up   != oldsigs.cts_up   ? MgslEvent_CtsActive:0)   +
2729 			  (newsigs.cts_down != oldsigs.cts_down ? MgslEvent_CtsInactive:0) +
2730 			  (newsigs.ri_up    != oldsigs.ri_up    ? MgslEvent_RiActive:0)    +
2731 			  (newsigs.ri_down  != oldsigs.ri_down  ? MgslEvent_RiInactive:0)  +
2732 			  (cnow.exithunt    != cprev.exithunt   ? MgslEvent_ExitHuntMode:0) +
2733 			  (cnow.rxidle      != cprev.rxidle     ? MgslEvent_IdleReceived:0) );
2734 		if (events)
2735 			break;
2736 
2737 		cprev = cnow;
2738 		oldsigs = newsigs;
2739 	}
2740 
2741 	remove_wait_queue(&info->event_wait_q, &wait);
2742 	set_current_state(TASK_RUNNING);
2743 
2744 
2745 	if (mask & (MgslEvent_ExitHuntMode + MgslEvent_IdleReceived)) {
2746 		spin_lock_irqsave(&info->lock,flags);
2747 		if (!waitqueue_active(&info->event_wait_q)) {
2748 			/* disable enable exit hunt mode/idle rcvd IRQs */
2749 			wr_reg16(info, SCR,
2750 				(unsigned short)(rd_reg16(info, SCR) & ~IRQ_RXIDLE));
2751 		}
2752 		spin_unlock_irqrestore(&info->lock,flags);
2753 	}
2754 exit:
2755 	if (rc == 0)
2756 		rc = put_user(events, mask_ptr);
2757 	return rc;
2758 }
2759 
2760 static int get_interface(struct slgt_info *info, int __user *if_mode)
2761 {
2762 	DBGINFO(("%s get_interface=%x\n", info->device_name, info->if_mode));
2763 	if (put_user(info->if_mode, if_mode))
2764 		return -EFAULT;
2765 	return 0;
2766 }
2767 
2768 static int set_interface(struct slgt_info *info, int if_mode)
2769 {
2770  	unsigned long flags;
2771 	unsigned short val;
2772 
2773 	DBGINFO(("%s set_interface=%x)\n", info->device_name, if_mode));
2774 	spin_lock_irqsave(&info->lock,flags);
2775 	info->if_mode = if_mode;
2776 
2777 	msc_set_vcr(info);
2778 
2779 	/* TCR (tx control) 07  1=RTS driver control */
2780 	val = rd_reg16(info, TCR);
2781 	if (info->if_mode & MGSL_INTERFACE_RTS_EN)
2782 		val |= BIT7;
2783 	else
2784 		val &= ~BIT7;
2785 	wr_reg16(info, TCR, val);
2786 
2787 	spin_unlock_irqrestore(&info->lock,flags);
2788 	return 0;
2789 }
2790 
2791 static int get_xsync(struct slgt_info *info, int __user *xsync)
2792 {
2793 	DBGINFO(("%s get_xsync=%x\n", info->device_name, info->xsync));
2794 	if (put_user(info->xsync, xsync))
2795 		return -EFAULT;
2796 	return 0;
2797 }
2798 
2799 /*
2800  * set extended sync pattern (1 to 4 bytes) for extended sync mode
2801  *
2802  * sync pattern is contained in least significant bytes of value
2803  * most significant byte of sync pattern is oldest (1st sent/detected)
2804  */
2805 static int set_xsync(struct slgt_info *info, int xsync)
2806 {
2807 	unsigned long flags;
2808 
2809 	DBGINFO(("%s set_xsync=%x)\n", info->device_name, xsync));
2810 	spin_lock_irqsave(&info->lock, flags);
2811 	info->xsync = xsync;
2812 	wr_reg32(info, XSR, xsync);
2813 	spin_unlock_irqrestore(&info->lock, flags);
2814 	return 0;
2815 }
2816 
2817 static int get_xctrl(struct slgt_info *info, int __user *xctrl)
2818 {
2819 	DBGINFO(("%s get_xctrl=%x\n", info->device_name, info->xctrl));
2820 	if (put_user(info->xctrl, xctrl))
2821 		return -EFAULT;
2822 	return 0;
2823 }
2824 
2825 /*
2826  * set extended control options
2827  *
2828  * xctrl[31:19] reserved, must be zero
2829  * xctrl[18:17] extended sync pattern length in bytes
2830  *              00 = 1 byte  in xsr[7:0]
2831  *              01 = 2 bytes in xsr[15:0]
2832  *              10 = 3 bytes in xsr[23:0]
2833  *              11 = 4 bytes in xsr[31:0]
2834  * xctrl[16]    1 = enable terminal count, 0=disabled
2835  * xctrl[15:0]  receive terminal count for fixed length packets
2836  *              value is count minus one (0 = 1 byte packet)
2837  *              when terminal count is reached, receiver
2838  *              automatically returns to hunt mode and receive
2839  *              FIFO contents are flushed to DMA buffers with
2840  *              end of frame (EOF) status
2841  */
2842 static int set_xctrl(struct slgt_info *info, int xctrl)
2843 {
2844 	unsigned long flags;
2845 
2846 	DBGINFO(("%s set_xctrl=%x)\n", info->device_name, xctrl));
2847 	spin_lock_irqsave(&info->lock, flags);
2848 	info->xctrl = xctrl;
2849 	wr_reg32(info, XCR, xctrl);
2850 	spin_unlock_irqrestore(&info->lock, flags);
2851 	return 0;
2852 }
2853 
2854 /*
2855  * set general purpose IO pin state and direction
2856  *
2857  * user_gpio fields:
2858  * state   each bit indicates a pin state
2859  * smask   set bit indicates pin state to set
2860  * dir     each bit indicates a pin direction (0=input, 1=output)
2861  * dmask   set bit indicates pin direction to set
2862  */
2863 static int set_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
2864 {
2865  	unsigned long flags;
2866 	struct gpio_desc gpio;
2867 	__u32 data;
2868 
2869 	if (!info->gpio_present)
2870 		return -EINVAL;
2871 	if (copy_from_user(&gpio, user_gpio, sizeof(gpio)))
2872 		return -EFAULT;
2873 	DBGINFO(("%s set_gpio state=%08x smask=%08x dir=%08x dmask=%08x\n",
2874 		 info->device_name, gpio.state, gpio.smask,
2875 		 gpio.dir, gpio.dmask));
2876 
2877 	spin_lock_irqsave(&info->port_array[0]->lock, flags);
2878 	if (gpio.dmask) {
2879 		data = rd_reg32(info, IODR);
2880 		data |= gpio.dmask & gpio.dir;
2881 		data &= ~(gpio.dmask & ~gpio.dir);
2882 		wr_reg32(info, IODR, data);
2883 	}
2884 	if (gpio.smask) {
2885 		data = rd_reg32(info, IOVR);
2886 		data |= gpio.smask & gpio.state;
2887 		data &= ~(gpio.smask & ~gpio.state);
2888 		wr_reg32(info, IOVR, data);
2889 	}
2890 	spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
2891 
2892 	return 0;
2893 }
2894 
2895 /*
2896  * get general purpose IO pin state and direction
2897  */
2898 static int get_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
2899 {
2900 	struct gpio_desc gpio;
2901 	if (!info->gpio_present)
2902 		return -EINVAL;
2903 	gpio.state = rd_reg32(info, IOVR);
2904 	gpio.smask = 0xffffffff;
2905 	gpio.dir   = rd_reg32(info, IODR);
2906 	gpio.dmask = 0xffffffff;
2907 	if (copy_to_user(user_gpio, &gpio, sizeof(gpio)))
2908 		return -EFAULT;
2909 	DBGINFO(("%s get_gpio state=%08x dir=%08x\n",
2910 		 info->device_name, gpio.state, gpio.dir));
2911 	return 0;
2912 }
2913 
2914 /*
2915  * conditional wait facility
2916  */
2917 static void init_cond_wait(struct cond_wait *w, unsigned int data)
2918 {
2919 	init_waitqueue_head(&w->q);
2920 	init_waitqueue_entry(&w->wait, current);
2921 	w->data = data;
2922 }
2923 
2924 static void add_cond_wait(struct cond_wait **head, struct cond_wait *w)
2925 {
2926 	set_current_state(TASK_INTERRUPTIBLE);
2927 	add_wait_queue(&w->q, &w->wait);
2928 	w->next = *head;
2929 	*head = w;
2930 }
2931 
2932 static void remove_cond_wait(struct cond_wait **head, struct cond_wait *cw)
2933 {
2934 	struct cond_wait *w, *prev;
2935 	remove_wait_queue(&cw->q, &cw->wait);
2936 	set_current_state(TASK_RUNNING);
2937 	for (w = *head, prev = NULL ; w != NULL ; prev = w, w = w->next) {
2938 		if (w == cw) {
2939 			if (prev != NULL)
2940 				prev->next = w->next;
2941 			else
2942 				*head = w->next;
2943 			break;
2944 		}
2945 	}
2946 }
2947 
2948 static void flush_cond_wait(struct cond_wait **head)
2949 {
2950 	while (*head != NULL) {
2951 		wake_up_interruptible(&(*head)->q);
2952 		*head = (*head)->next;
2953 	}
2954 }
2955 
2956 /*
2957  * wait for general purpose I/O pin(s) to enter specified state
2958  *
2959  * user_gpio fields:
2960  * state - bit indicates target pin state
2961  * smask - set bit indicates watched pin
2962  *
2963  * The wait ends when at least one watched pin enters the specified
2964  * state. When 0 (no error) is returned, user_gpio->state is set to the
2965  * state of all GPIO pins when the wait ends.
2966  *
2967  * Note: Each pin may be a dedicated input, dedicated output, or
2968  * configurable input/output. The number and configuration of pins
2969  * varies with the specific adapter model. Only input pins (dedicated
2970  * or configured) can be monitored with this function.
2971  */
2972 static int wait_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
2973 {
2974  	unsigned long flags;
2975 	int rc = 0;
2976 	struct gpio_desc gpio;
2977 	struct cond_wait wait;
2978 	u32 state;
2979 
2980 	if (!info->gpio_present)
2981 		return -EINVAL;
2982 	if (copy_from_user(&gpio, user_gpio, sizeof(gpio)))
2983 		return -EFAULT;
2984 	DBGINFO(("%s wait_gpio() state=%08x smask=%08x\n",
2985 		 info->device_name, gpio.state, gpio.smask));
2986 	/* ignore output pins identified by set IODR bit */
2987 	if ((gpio.smask &= ~rd_reg32(info, IODR)) == 0)
2988 		return -EINVAL;
2989 	init_cond_wait(&wait, gpio.smask);
2990 
2991 	spin_lock_irqsave(&info->port_array[0]->lock, flags);
2992 	/* enable interrupts for watched pins */
2993 	wr_reg32(info, IOER, rd_reg32(info, IOER) | gpio.smask);
2994 	/* get current pin states */
2995 	state = rd_reg32(info, IOVR);
2996 
2997 	if (gpio.smask & ~(state ^ gpio.state)) {
2998 		/* already in target state */
2999 		gpio.state = state;
3000 	} else {
3001 		/* wait for target state */
3002 		add_cond_wait(&info->gpio_wait_q, &wait);
3003 		spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
3004 		schedule();
3005 		if (signal_pending(current))
3006 			rc = -ERESTARTSYS;
3007 		else
3008 			gpio.state = wait.data;
3009 		spin_lock_irqsave(&info->port_array[0]->lock, flags);
3010 		remove_cond_wait(&info->gpio_wait_q, &wait);
3011 	}
3012 
3013 	/* disable all GPIO interrupts if no waiting processes */
3014 	if (info->gpio_wait_q == NULL)
3015 		wr_reg32(info, IOER, 0);
3016 	spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
3017 
3018 	if ((rc == 0) && copy_to_user(user_gpio, &gpio, sizeof(gpio)))
3019 		rc = -EFAULT;
3020 	return rc;
3021 }
3022 
3023 static int modem_input_wait(struct slgt_info *info,int arg)
3024 {
3025  	unsigned long flags;
3026 	int rc;
3027 	struct mgsl_icount cprev, cnow;
3028 	DECLARE_WAITQUEUE(wait, current);
3029 
3030 	/* save current irq counts */
3031 	spin_lock_irqsave(&info->lock,flags);
3032 	cprev = info->icount;
3033 	add_wait_queue(&info->status_event_wait_q, &wait);
3034 	set_current_state(TASK_INTERRUPTIBLE);
3035 	spin_unlock_irqrestore(&info->lock,flags);
3036 
3037 	for(;;) {
3038 		schedule();
3039 		if (signal_pending(current)) {
3040 			rc = -ERESTARTSYS;
3041 			break;
3042 		}
3043 
3044 		/* get new irq counts */
3045 		spin_lock_irqsave(&info->lock,flags);
3046 		cnow = info->icount;
3047 		set_current_state(TASK_INTERRUPTIBLE);
3048 		spin_unlock_irqrestore(&info->lock,flags);
3049 
3050 		/* if no change, wait aborted for some reason */
3051 		if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
3052 		    cnow.dcd == cprev.dcd && cnow.cts == cprev.cts) {
3053 			rc = -EIO;
3054 			break;
3055 		}
3056 
3057 		/* check for change in caller specified modem input */
3058 		if ((arg & TIOCM_RNG && cnow.rng != cprev.rng) ||
3059 		    (arg & TIOCM_DSR && cnow.dsr != cprev.dsr) ||
3060 		    (arg & TIOCM_CD  && cnow.dcd != cprev.dcd) ||
3061 		    (arg & TIOCM_CTS && cnow.cts != cprev.cts)) {
3062 			rc = 0;
3063 			break;
3064 		}
3065 
3066 		cprev = cnow;
3067 	}
3068 	remove_wait_queue(&info->status_event_wait_q, &wait);
3069 	set_current_state(TASK_RUNNING);
3070 	return rc;
3071 }
3072 
3073 /*
3074  *  return state of serial control and status signals
3075  */
3076 static int tiocmget(struct tty_struct *tty)
3077 {
3078 	struct slgt_info *info = tty->driver_data;
3079 	unsigned int result;
3080  	unsigned long flags;
3081 
3082 	spin_lock_irqsave(&info->lock,flags);
3083  	get_gtsignals(info);
3084 	spin_unlock_irqrestore(&info->lock,flags);
3085 
3086 	result = ((info->signals & SerialSignal_RTS) ? TIOCM_RTS:0) +
3087 		((info->signals & SerialSignal_DTR) ? TIOCM_DTR:0) +
3088 		((info->signals & SerialSignal_DCD) ? TIOCM_CAR:0) +
3089 		((info->signals & SerialSignal_RI)  ? TIOCM_RNG:0) +
3090 		((info->signals & SerialSignal_DSR) ? TIOCM_DSR:0) +
3091 		((info->signals & SerialSignal_CTS) ? TIOCM_CTS:0);
3092 
3093 	DBGINFO(("%s tiocmget value=%08X\n", info->device_name, result));
3094 	return result;
3095 }
3096 
3097 /*
3098  * set modem control signals (DTR/RTS)
3099  *
3100  * 	cmd	signal command: TIOCMBIS = set bit TIOCMBIC = clear bit
3101  *		TIOCMSET = set/clear signal values
3102  * 	value	bit mask for command
3103  */
3104 static int tiocmset(struct tty_struct *tty,
3105 		    unsigned int set, unsigned int clear)
3106 {
3107 	struct slgt_info *info = tty->driver_data;
3108  	unsigned long flags;
3109 
3110 	DBGINFO(("%s tiocmset(%x,%x)\n", info->device_name, set, clear));
3111 
3112 	if (set & TIOCM_RTS)
3113 		info->signals |= SerialSignal_RTS;
3114 	if (set & TIOCM_DTR)
3115 		info->signals |= SerialSignal_DTR;
3116 	if (clear & TIOCM_RTS)
3117 		info->signals &= ~SerialSignal_RTS;
3118 	if (clear & TIOCM_DTR)
3119 		info->signals &= ~SerialSignal_DTR;
3120 
3121 	spin_lock_irqsave(&info->lock,flags);
3122 	set_gtsignals(info);
3123 	spin_unlock_irqrestore(&info->lock,flags);
3124 	return 0;
3125 }
3126 
3127 static bool carrier_raised(struct tty_port *port)
3128 {
3129 	unsigned long flags;
3130 	struct slgt_info *info = container_of(port, struct slgt_info, port);
3131 
3132 	spin_lock_irqsave(&info->lock,flags);
3133 	get_gtsignals(info);
3134 	spin_unlock_irqrestore(&info->lock,flags);
3135 
3136 	return info->signals & SerialSignal_DCD;
3137 }
3138 
3139 static void dtr_rts(struct tty_port *port, bool active)
3140 {
3141 	unsigned long flags;
3142 	struct slgt_info *info = container_of(port, struct slgt_info, port);
3143 
3144 	spin_lock_irqsave(&info->lock,flags);
3145 	if (active)
3146 		info->signals |= SerialSignal_RTS | SerialSignal_DTR;
3147 	else
3148 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
3149 	set_gtsignals(info);
3150 	spin_unlock_irqrestore(&info->lock,flags);
3151 }
3152 
3153 
3154 /*
3155  *  block current process until the device is ready to open
3156  */
3157 static int block_til_ready(struct tty_struct *tty, struct file *filp,
3158 			   struct slgt_info *info)
3159 {
3160 	DECLARE_WAITQUEUE(wait, current);
3161 	int		retval;
3162 	bool		do_clocal = false;
3163 	unsigned long	flags;
3164 	bool		cd;
3165 	struct tty_port *port = &info->port;
3166 
3167 	DBGINFO(("%s block_til_ready\n", tty->driver->name));
3168 
3169 	if (filp->f_flags & O_NONBLOCK || tty_io_error(tty)) {
3170 		/* nonblock mode is set or port is not enabled */
3171 		tty_port_set_active(port, true);
3172 		return 0;
3173 	}
3174 
3175 	if (C_CLOCAL(tty))
3176 		do_clocal = true;
3177 
3178 	/* Wait for carrier detect and the line to become
3179 	 * free (i.e., not in use by the callout).  While we are in
3180 	 * this loop, port->count is dropped by one, so that
3181 	 * close() knows when to free things.  We restore it upon
3182 	 * exit, either normal or abnormal.
3183 	 */
3184 
3185 	retval = 0;
3186 	add_wait_queue(&port->open_wait, &wait);
3187 
3188 	spin_lock_irqsave(&info->lock, flags);
3189 	port->count--;
3190 	spin_unlock_irqrestore(&info->lock, flags);
3191 	port->blocked_open++;
3192 
3193 	while (1) {
3194 		if (C_BAUD(tty) && tty_port_initialized(port))
3195 			tty_port_raise_dtr_rts(port);
3196 
3197 		set_current_state(TASK_INTERRUPTIBLE);
3198 
3199 		if (tty_hung_up_p(filp) || !tty_port_initialized(port)) {
3200 			retval = (port->flags & ASYNC_HUP_NOTIFY) ?
3201 					-EAGAIN : -ERESTARTSYS;
3202 			break;
3203 		}
3204 
3205 		cd = tty_port_carrier_raised(port);
3206 		if (do_clocal || cd)
3207 			break;
3208 
3209 		if (signal_pending(current)) {
3210 			retval = -ERESTARTSYS;
3211 			break;
3212 		}
3213 
3214 		DBGINFO(("%s block_til_ready wait\n", tty->driver->name));
3215 		tty_unlock(tty);
3216 		schedule();
3217 		tty_lock(tty);
3218 	}
3219 
3220 	set_current_state(TASK_RUNNING);
3221 	remove_wait_queue(&port->open_wait, &wait);
3222 
3223 	if (!tty_hung_up_p(filp))
3224 		port->count++;
3225 	port->blocked_open--;
3226 
3227 	if (!retval)
3228 		tty_port_set_active(port, true);
3229 
3230 	DBGINFO(("%s block_til_ready ready, rc=%d\n", tty->driver->name, retval));
3231 	return retval;
3232 }
3233 
3234 /*
3235  * allocate buffers used for calling line discipline receive_buf
3236  * directly in synchronous mode
3237  * note: add 5 bytes to max frame size to allow appending
3238  * 32-bit CRC and status byte when configured to do so
3239  */
3240 static int alloc_tmp_rbuf(struct slgt_info *info)
3241 {
3242 	info->tmp_rbuf = kmalloc(info->max_frame_size + 5, GFP_KERNEL);
3243 	if (info->tmp_rbuf == NULL)
3244 		return -ENOMEM;
3245 
3246 	return 0;
3247 }
3248 
3249 static void free_tmp_rbuf(struct slgt_info *info)
3250 {
3251 	kfree(info->tmp_rbuf);
3252 	info->tmp_rbuf = NULL;
3253 }
3254 
3255 /*
3256  * allocate DMA descriptor lists.
3257  */
3258 static int alloc_desc(struct slgt_info *info)
3259 {
3260 	unsigned int i;
3261 	unsigned int pbufs;
3262 
3263 	/* allocate memory to hold descriptor lists */
3264 	info->bufs = dma_alloc_coherent(&info->pdev->dev, DESC_LIST_SIZE,
3265 					&info->bufs_dma_addr, GFP_KERNEL);
3266 	if (info->bufs == NULL)
3267 		return -ENOMEM;
3268 
3269 	info->rbufs = (struct slgt_desc*)info->bufs;
3270 	info->tbufs = ((struct slgt_desc*)info->bufs) + info->rbuf_count;
3271 
3272 	pbufs = (unsigned int)info->bufs_dma_addr;
3273 
3274 	/*
3275 	 * Build circular lists of descriptors
3276 	 */
3277 
3278 	for (i=0; i < info->rbuf_count; i++) {
3279 		/* physical address of this descriptor */
3280 		info->rbufs[i].pdesc = pbufs + (i * sizeof(struct slgt_desc));
3281 
3282 		/* physical address of next descriptor */
3283 		if (i == info->rbuf_count - 1)
3284 			info->rbufs[i].next = cpu_to_le32(pbufs);
3285 		else
3286 			info->rbufs[i].next = cpu_to_le32(pbufs + ((i+1) * sizeof(struct slgt_desc)));
3287 		set_desc_count(info->rbufs[i], DMABUFSIZE);
3288 	}
3289 
3290 	for (i=0; i < info->tbuf_count; i++) {
3291 		/* physical address of this descriptor */
3292 		info->tbufs[i].pdesc = pbufs + ((info->rbuf_count + i) * sizeof(struct slgt_desc));
3293 
3294 		/* physical address of next descriptor */
3295 		if (i == info->tbuf_count - 1)
3296 			info->tbufs[i].next = cpu_to_le32(pbufs + info->rbuf_count * sizeof(struct slgt_desc));
3297 		else
3298 			info->tbufs[i].next = cpu_to_le32(pbufs + ((info->rbuf_count + i + 1) * sizeof(struct slgt_desc)));
3299 	}
3300 
3301 	return 0;
3302 }
3303 
3304 static void free_desc(struct slgt_info *info)
3305 {
3306 	if (info->bufs != NULL) {
3307 		dma_free_coherent(&info->pdev->dev, DESC_LIST_SIZE,
3308 				  info->bufs, info->bufs_dma_addr);
3309 		info->bufs  = NULL;
3310 		info->rbufs = NULL;
3311 		info->tbufs = NULL;
3312 	}
3313 }
3314 
3315 static int alloc_bufs(struct slgt_info *info, struct slgt_desc *bufs, int count)
3316 {
3317 	int i;
3318 	for (i=0; i < count; i++) {
3319 		bufs[i].buf = dma_alloc_coherent(&info->pdev->dev, DMABUFSIZE,
3320 						 &bufs[i].buf_dma_addr, GFP_KERNEL);
3321 		if (!bufs[i].buf)
3322 			return -ENOMEM;
3323 		bufs[i].pbuf  = cpu_to_le32((unsigned int)bufs[i].buf_dma_addr);
3324 	}
3325 	return 0;
3326 }
3327 
3328 static void free_bufs(struct slgt_info *info, struct slgt_desc *bufs, int count)
3329 {
3330 	int i;
3331 	for (i=0; i < count; i++) {
3332 		if (bufs[i].buf == NULL)
3333 			continue;
3334 		dma_free_coherent(&info->pdev->dev, DMABUFSIZE, bufs[i].buf,
3335 				  bufs[i].buf_dma_addr);
3336 		bufs[i].buf = NULL;
3337 	}
3338 }
3339 
3340 static int alloc_dma_bufs(struct slgt_info *info)
3341 {
3342 	info->rbuf_count = 32;
3343 	info->tbuf_count = 32;
3344 
3345 	if (alloc_desc(info) < 0 ||
3346 	    alloc_bufs(info, info->rbufs, info->rbuf_count) < 0 ||
3347 	    alloc_bufs(info, info->tbufs, info->tbuf_count) < 0 ||
3348 	    alloc_tmp_rbuf(info) < 0) {
3349 		DBGERR(("%s DMA buffer alloc fail\n", info->device_name));
3350 		return -ENOMEM;
3351 	}
3352 	reset_rbufs(info);
3353 	return 0;
3354 }
3355 
3356 static void free_dma_bufs(struct slgt_info *info)
3357 {
3358 	if (info->bufs) {
3359 		free_bufs(info, info->rbufs, info->rbuf_count);
3360 		free_bufs(info, info->tbufs, info->tbuf_count);
3361 		free_desc(info);
3362 	}
3363 	free_tmp_rbuf(info);
3364 }
3365 
3366 static int claim_resources(struct slgt_info *info)
3367 {
3368 	if (request_mem_region(info->phys_reg_addr, SLGT_REG_SIZE, "synclink_gt") == NULL) {
3369 		DBGERR(("%s reg addr conflict, addr=%08X\n",
3370 			info->device_name, info->phys_reg_addr));
3371 		info->init_error = DiagStatus_AddressConflict;
3372 		goto errout;
3373 	}
3374 	else
3375 		info->reg_addr_requested = true;
3376 
3377 	info->reg_addr = ioremap(info->phys_reg_addr, SLGT_REG_SIZE);
3378 	if (!info->reg_addr) {
3379 		DBGERR(("%s can't map device registers, addr=%08X\n",
3380 			info->device_name, info->phys_reg_addr));
3381 		info->init_error = DiagStatus_CantAssignPciResources;
3382 		goto errout;
3383 	}
3384 	return 0;
3385 
3386 errout:
3387 	release_resources(info);
3388 	return -ENODEV;
3389 }
3390 
3391 static void release_resources(struct slgt_info *info)
3392 {
3393 	if (info->irq_requested) {
3394 		free_irq(info->irq_level, info);
3395 		info->irq_requested = false;
3396 	}
3397 
3398 	if (info->reg_addr_requested) {
3399 		release_mem_region(info->phys_reg_addr, SLGT_REG_SIZE);
3400 		info->reg_addr_requested = false;
3401 	}
3402 
3403 	if (info->reg_addr) {
3404 		iounmap(info->reg_addr);
3405 		info->reg_addr = NULL;
3406 	}
3407 }
3408 
3409 /* Add the specified device instance data structure to the
3410  * global linked list of devices and increment the device count.
3411  */
3412 static void add_device(struct slgt_info *info)
3413 {
3414 	char *devstr;
3415 
3416 	info->next_device = NULL;
3417 	info->line = slgt_device_count;
3418 	sprintf(info->device_name, "%s%d", tty_dev_prefix, info->line);
3419 
3420 	if (info->line < MAX_DEVICES) {
3421 		if (maxframe[info->line])
3422 			info->max_frame_size = maxframe[info->line];
3423 	}
3424 
3425 	slgt_device_count++;
3426 
3427 	if (!slgt_device_list)
3428 		slgt_device_list = info;
3429 	else {
3430 		struct slgt_info *current_dev = slgt_device_list;
3431 		while(current_dev->next_device)
3432 			current_dev = current_dev->next_device;
3433 		current_dev->next_device = info;
3434 	}
3435 
3436 	if (info->max_frame_size < 4096)
3437 		info->max_frame_size = 4096;
3438 	else if (info->max_frame_size > 65535)
3439 		info->max_frame_size = 65535;
3440 
3441 	switch(info->pdev->device) {
3442 	case SYNCLINK_GT_DEVICE_ID:
3443 		devstr = "GT";
3444 		break;
3445 	case SYNCLINK_GT2_DEVICE_ID:
3446 		devstr = "GT2";
3447 		break;
3448 	case SYNCLINK_GT4_DEVICE_ID:
3449 		devstr = "GT4";
3450 		break;
3451 	case SYNCLINK_AC_DEVICE_ID:
3452 		devstr = "AC";
3453 		info->params.mode = MGSL_MODE_ASYNC;
3454 		break;
3455 	default:
3456 		devstr = "(unknown model)";
3457 	}
3458 	printk("SyncLink %s %s IO=%08x IRQ=%d MaxFrameSize=%u\n",
3459 		devstr, info->device_name, info->phys_reg_addr,
3460 		info->irq_level, info->max_frame_size);
3461 
3462 #if SYNCLINK_GENERIC_HDLC
3463 	hdlcdev_init(info);
3464 #endif
3465 }
3466 
3467 static const struct tty_port_operations slgt_port_ops = {
3468 	.carrier_raised = carrier_raised,
3469 	.dtr_rts = dtr_rts,
3470 };
3471 
3472 /*
3473  *  allocate device instance structure, return NULL on failure
3474  */
3475 static struct slgt_info *alloc_dev(int adapter_num, int port_num, struct pci_dev *pdev)
3476 {
3477 	struct slgt_info *info;
3478 
3479 	info = kzalloc(sizeof(struct slgt_info), GFP_KERNEL);
3480 
3481 	if (!info) {
3482 		DBGERR(("%s device alloc failed adapter=%d port=%d\n",
3483 			driver_name, adapter_num, port_num));
3484 	} else {
3485 		tty_port_init(&info->port);
3486 		info->port.ops = &slgt_port_ops;
3487 		INIT_WORK(&info->task, bh_handler);
3488 		info->max_frame_size = 4096;
3489 		info->base_clock = 14745600;
3490 		info->rbuf_fill_level = DMABUFSIZE;
3491 		init_waitqueue_head(&info->status_event_wait_q);
3492 		init_waitqueue_head(&info->event_wait_q);
3493 		spin_lock_init(&info->netlock);
3494 		memcpy(&info->params,&default_params,sizeof(MGSL_PARAMS));
3495 		info->idle_mode = HDLC_TXIDLE_FLAGS;
3496 		info->adapter_num = adapter_num;
3497 		info->port_num = port_num;
3498 
3499 		timer_setup(&info->tx_timer, tx_timeout, 0);
3500 		timer_setup(&info->rx_timer, rx_timeout, 0);
3501 
3502 		/* Copy configuration info to device instance data */
3503 		info->pdev = pdev;
3504 		info->irq_level = pdev->irq;
3505 		info->phys_reg_addr = pci_resource_start(pdev,0);
3506 
3507 		info->bus_type = MGSL_BUS_TYPE_PCI;
3508 		info->irq_flags = IRQF_SHARED;
3509 
3510 		info->init_error = -1; /* assume error, set to 0 on successful init */
3511 	}
3512 
3513 	return info;
3514 }
3515 
3516 static void device_init(int adapter_num, struct pci_dev *pdev)
3517 {
3518 	struct slgt_info *port_array[SLGT_MAX_PORTS];
3519 	int i;
3520 	int port_count = 1;
3521 
3522 	if (pdev->device == SYNCLINK_GT2_DEVICE_ID)
3523 		port_count = 2;
3524 	else if (pdev->device == SYNCLINK_GT4_DEVICE_ID)
3525 		port_count = 4;
3526 
3527 	/* allocate device instances for all ports */
3528 	for (i=0; i < port_count; ++i) {
3529 		port_array[i] = alloc_dev(adapter_num, i, pdev);
3530 		if (port_array[i] == NULL) {
3531 			for (--i; i >= 0; --i) {
3532 				tty_port_destroy(&port_array[i]->port);
3533 				kfree(port_array[i]);
3534 			}
3535 			return;
3536 		}
3537 	}
3538 
3539 	/* give copy of port_array to all ports and add to device list  */
3540 	for (i=0; i < port_count; ++i) {
3541 		memcpy(port_array[i]->port_array, port_array, sizeof(port_array));
3542 		add_device(port_array[i]);
3543 		port_array[i]->port_count = port_count;
3544 		spin_lock_init(&port_array[i]->lock);
3545 	}
3546 
3547 	/* Allocate and claim adapter resources */
3548 	if (!claim_resources(port_array[0])) {
3549 
3550 		alloc_dma_bufs(port_array[0]);
3551 
3552 		/* copy resource information from first port to others */
3553 		for (i = 1; i < port_count; ++i) {
3554 			port_array[i]->irq_level = port_array[0]->irq_level;
3555 			port_array[i]->reg_addr  = port_array[0]->reg_addr;
3556 			alloc_dma_bufs(port_array[i]);
3557 		}
3558 
3559 		if (request_irq(port_array[0]->irq_level,
3560 					slgt_interrupt,
3561 					port_array[0]->irq_flags,
3562 					port_array[0]->device_name,
3563 					port_array[0]) < 0) {
3564 			DBGERR(("%s request_irq failed IRQ=%d\n",
3565 				port_array[0]->device_name,
3566 				port_array[0]->irq_level));
3567 		} else {
3568 			port_array[0]->irq_requested = true;
3569 			adapter_test(port_array[0]);
3570 			for (i=1 ; i < port_count ; i++) {
3571 				port_array[i]->init_error = port_array[0]->init_error;
3572 				port_array[i]->gpio_present = port_array[0]->gpio_present;
3573 			}
3574 		}
3575 	}
3576 
3577 	for (i = 0; i < port_count; ++i) {
3578 		struct slgt_info *info = port_array[i];
3579 		tty_port_register_device(&info->port, serial_driver, info->line,
3580 				&info->pdev->dev);
3581 	}
3582 }
3583 
3584 static int init_one(struct pci_dev *dev,
3585 			      const struct pci_device_id *ent)
3586 {
3587 	if (pci_enable_device(dev)) {
3588 		printk("error enabling pci device %p\n", dev);
3589 		return -EIO;
3590 	}
3591 	pci_set_master(dev);
3592 	device_init(slgt_device_count, dev);
3593 	return 0;
3594 }
3595 
3596 static void remove_one(struct pci_dev *dev)
3597 {
3598 }
3599 
3600 static const struct tty_operations ops = {
3601 	.open = open,
3602 	.close = close,
3603 	.write = write,
3604 	.put_char = put_char,
3605 	.flush_chars = flush_chars,
3606 	.write_room = write_room,
3607 	.chars_in_buffer = chars_in_buffer,
3608 	.flush_buffer = flush_buffer,
3609 	.ioctl = ioctl,
3610 	.compat_ioctl = slgt_compat_ioctl,
3611 	.throttle = throttle,
3612 	.unthrottle = unthrottle,
3613 	.send_xchar = send_xchar,
3614 	.break_ctl = set_break,
3615 	.wait_until_sent = wait_until_sent,
3616 	.set_termios = set_termios,
3617 	.stop = tx_hold,
3618 	.start = tx_release,
3619 	.hangup = hangup,
3620 	.tiocmget = tiocmget,
3621 	.tiocmset = tiocmset,
3622 	.get_icount = get_icount,
3623 	.proc_show = synclink_gt_proc_show,
3624 };
3625 
3626 static void slgt_cleanup(void)
3627 {
3628 	struct slgt_info *info;
3629 	struct slgt_info *tmp;
3630 
3631 	if (serial_driver) {
3632 		for (info=slgt_device_list ; info != NULL ; info=info->next_device)
3633 			tty_unregister_device(serial_driver, info->line);
3634 		tty_unregister_driver(serial_driver);
3635 		tty_driver_kref_put(serial_driver);
3636 	}
3637 
3638 	/* reset devices */
3639 	info = slgt_device_list;
3640 	while(info) {
3641 		reset_port(info);
3642 		info = info->next_device;
3643 	}
3644 
3645 	/* release devices */
3646 	info = slgt_device_list;
3647 	while(info) {
3648 #if SYNCLINK_GENERIC_HDLC
3649 		hdlcdev_exit(info);
3650 #endif
3651 		free_dma_bufs(info);
3652 		free_tmp_rbuf(info);
3653 		if (info->port_num == 0)
3654 			release_resources(info);
3655 		tmp = info;
3656 		info = info->next_device;
3657 		tty_port_destroy(&tmp->port);
3658 		kfree(tmp);
3659 	}
3660 
3661 	if (pci_registered)
3662 		pci_unregister_driver(&pci_driver);
3663 }
3664 
3665 /*
3666  *  Driver initialization entry point.
3667  */
3668 static int __init slgt_init(void)
3669 {
3670 	int rc;
3671 
3672 	serial_driver = tty_alloc_driver(MAX_DEVICES, TTY_DRIVER_REAL_RAW |
3673 			TTY_DRIVER_DYNAMIC_DEV);
3674 	if (IS_ERR(serial_driver)) {
3675 		printk("%s can't allocate tty driver\n", driver_name);
3676 		return PTR_ERR(serial_driver);
3677 	}
3678 
3679 	/* Initialize the tty_driver structure */
3680 
3681 	serial_driver->driver_name = "synclink_gt";
3682 	serial_driver->name = tty_dev_prefix;
3683 	serial_driver->major = ttymajor;
3684 	serial_driver->minor_start = 64;
3685 	serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
3686 	serial_driver->subtype = SERIAL_TYPE_NORMAL;
3687 	serial_driver->init_termios = tty_std_termios;
3688 	serial_driver->init_termios.c_cflag =
3689 		B9600 | CS8 | CREAD | HUPCL | CLOCAL;
3690 	serial_driver->init_termios.c_ispeed = 9600;
3691 	serial_driver->init_termios.c_ospeed = 9600;
3692 	tty_set_operations(serial_driver, &ops);
3693 	if ((rc = tty_register_driver(serial_driver)) < 0) {
3694 		DBGERR(("%s can't register serial driver\n", driver_name));
3695 		tty_driver_kref_put(serial_driver);
3696 		serial_driver = NULL;
3697 		goto error;
3698 	}
3699 
3700 	slgt_device_count = 0;
3701 	if ((rc = pci_register_driver(&pci_driver)) < 0) {
3702 		printk("%s pci_register_driver error=%d\n", driver_name, rc);
3703 		goto error;
3704 	}
3705 	pci_registered = true;
3706 
3707 	return 0;
3708 
3709 error:
3710 	slgt_cleanup();
3711 	return rc;
3712 }
3713 
3714 static void __exit slgt_exit(void)
3715 {
3716 	slgt_cleanup();
3717 }
3718 
3719 module_init(slgt_init);
3720 module_exit(slgt_exit);
3721 
3722 /*
3723  * register access routines
3724  */
3725 
3726 static inline void __iomem *calc_regaddr(struct slgt_info *info,
3727 					 unsigned int addr)
3728 {
3729 	void __iomem *reg_addr = info->reg_addr + addr;
3730 
3731 	if (addr >= 0x80)
3732 		reg_addr += info->port_num * 32;
3733 	else if (addr >= 0x40)
3734 		reg_addr += info->port_num * 16;
3735 
3736 	return reg_addr;
3737 }
3738 
3739 static __u8 rd_reg8(struct slgt_info *info, unsigned int addr)
3740 {
3741 	return readb(calc_regaddr(info, addr));
3742 }
3743 
3744 static void wr_reg8(struct slgt_info *info, unsigned int addr, __u8 value)
3745 {
3746 	writeb(value, calc_regaddr(info, addr));
3747 }
3748 
3749 static __u16 rd_reg16(struct slgt_info *info, unsigned int addr)
3750 {
3751 	return readw(calc_regaddr(info, addr));
3752 }
3753 
3754 static void wr_reg16(struct slgt_info *info, unsigned int addr, __u16 value)
3755 {
3756 	writew(value, calc_regaddr(info, addr));
3757 }
3758 
3759 static __u32 rd_reg32(struct slgt_info *info, unsigned int addr)
3760 {
3761 	return readl(calc_regaddr(info, addr));
3762 }
3763 
3764 static void wr_reg32(struct slgt_info *info, unsigned int addr, __u32 value)
3765 {
3766 	writel(value, calc_regaddr(info, addr));
3767 }
3768 
3769 static void rdma_reset(struct slgt_info *info)
3770 {
3771 	unsigned int i;
3772 
3773 	/* set reset bit */
3774 	wr_reg32(info, RDCSR, BIT1);
3775 
3776 	/* wait for enable bit cleared */
3777 	for(i=0 ; i < 1000 ; i++)
3778 		if (!(rd_reg32(info, RDCSR) & BIT0))
3779 			break;
3780 }
3781 
3782 static void tdma_reset(struct slgt_info *info)
3783 {
3784 	unsigned int i;
3785 
3786 	/* set reset bit */
3787 	wr_reg32(info, TDCSR, BIT1);
3788 
3789 	/* wait for enable bit cleared */
3790 	for(i=0 ; i < 1000 ; i++)
3791 		if (!(rd_reg32(info, TDCSR) & BIT0))
3792 			break;
3793 }
3794 
3795 /*
3796  * enable internal loopback
3797  * TxCLK and RxCLK are generated from BRG
3798  * and TxD is looped back to RxD internally.
3799  */
3800 static void enable_loopback(struct slgt_info *info)
3801 {
3802 	/* SCR (serial control) BIT2=loopback enable */
3803 	wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) | BIT2));
3804 
3805 	if (info->params.mode != MGSL_MODE_ASYNC) {
3806 		/* CCR (clock control)
3807 		 * 07..05  tx clock source (010 = BRG)
3808 		 * 04..02  rx clock source (010 = BRG)
3809 		 * 01      auxclk enable   (0 = disable)
3810 		 * 00      BRG enable      (1 = enable)
3811 		 *
3812 		 * 0100 1001
3813 		 */
3814 		wr_reg8(info, CCR, 0x49);
3815 
3816 		/* set speed if available, otherwise use default */
3817 		if (info->params.clock_speed)
3818 			set_rate(info, info->params.clock_speed);
3819 		else
3820 			set_rate(info, 3686400);
3821 	}
3822 }
3823 
3824 /*
3825  *  set baud rate generator to specified rate
3826  */
3827 static void set_rate(struct slgt_info *info, u32 rate)
3828 {
3829 	unsigned int div;
3830 	unsigned int osc = info->base_clock;
3831 
3832 	/* div = osc/rate - 1
3833 	 *
3834 	 * Round div up if osc/rate is not integer to
3835 	 * force to next slowest rate.
3836 	 */
3837 
3838 	if (rate) {
3839 		div = osc/rate;
3840 		if (!(osc % rate) && div)
3841 			div--;
3842 		wr_reg16(info, BDR, (unsigned short)div);
3843 	}
3844 }
3845 
3846 static void rx_stop(struct slgt_info *info)
3847 {
3848 	unsigned short val;
3849 
3850 	/* disable and reset receiver */
3851 	val = rd_reg16(info, RCR) & ~BIT1;          /* clear enable bit */
3852 	wr_reg16(info, RCR, (unsigned short)(val | BIT2)); /* set reset bit */
3853 	wr_reg16(info, RCR, val);                  /* clear reset bit */
3854 
3855 	slgt_irq_off(info, IRQ_RXOVER + IRQ_RXDATA + IRQ_RXIDLE);
3856 
3857 	/* clear pending rx interrupts */
3858 	wr_reg16(info, SSR, IRQ_RXIDLE + IRQ_RXOVER);
3859 
3860 	rdma_reset(info);
3861 
3862 	info->rx_enabled = false;
3863 	info->rx_restart = false;
3864 }
3865 
3866 static void rx_start(struct slgt_info *info)
3867 {
3868 	unsigned short val;
3869 
3870 	slgt_irq_off(info, IRQ_RXOVER + IRQ_RXDATA);
3871 
3872 	/* clear pending rx overrun IRQ */
3873 	wr_reg16(info, SSR, IRQ_RXOVER);
3874 
3875 	/* reset and disable receiver */
3876 	val = rd_reg16(info, RCR) & ~BIT1; /* clear enable bit */
3877 	wr_reg16(info, RCR, (unsigned short)(val | BIT2)); /* set reset bit */
3878 	wr_reg16(info, RCR, val);                  /* clear reset bit */
3879 
3880 	rdma_reset(info);
3881 	reset_rbufs(info);
3882 
3883 	if (info->rx_pio) {
3884 		/* rx request when rx FIFO not empty */
3885 		wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) & ~BIT14));
3886 		slgt_irq_on(info, IRQ_RXDATA);
3887 		if (info->params.mode == MGSL_MODE_ASYNC) {
3888 			/* enable saving of rx status */
3889 			wr_reg32(info, RDCSR, BIT6);
3890 		}
3891 	} else {
3892 		/* rx request when rx FIFO half full */
3893 		wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) | BIT14));
3894 		/* set 1st descriptor address */
3895 		wr_reg32(info, RDDAR, info->rbufs[0].pdesc);
3896 
3897 		if (info->params.mode != MGSL_MODE_ASYNC) {
3898 			/* enable rx DMA and DMA interrupt */
3899 			wr_reg32(info, RDCSR, (BIT2 + BIT0));
3900 		} else {
3901 			/* enable saving of rx status, rx DMA and DMA interrupt */
3902 			wr_reg32(info, RDCSR, (BIT6 + BIT2 + BIT0));
3903 		}
3904 	}
3905 
3906 	slgt_irq_on(info, IRQ_RXOVER);
3907 
3908 	/* enable receiver */
3909 	wr_reg16(info, RCR, (unsigned short)(rd_reg16(info, RCR) | BIT1));
3910 
3911 	info->rx_restart = false;
3912 	info->rx_enabled = true;
3913 }
3914 
3915 static void tx_start(struct slgt_info *info)
3916 {
3917 	if (!info->tx_enabled) {
3918 		wr_reg16(info, TCR,
3919 			 (unsigned short)((rd_reg16(info, TCR) | BIT1) & ~BIT2));
3920 		info->tx_enabled = true;
3921 	}
3922 
3923 	if (desc_count(info->tbufs[info->tbuf_start])) {
3924 		info->drop_rts_on_tx_done = false;
3925 
3926 		if (info->params.mode != MGSL_MODE_ASYNC) {
3927 			if (info->params.flags & HDLC_FLAG_AUTO_RTS) {
3928 				get_gtsignals(info);
3929 				if (!(info->signals & SerialSignal_RTS)) {
3930 					info->signals |= SerialSignal_RTS;
3931 					set_gtsignals(info);
3932 					info->drop_rts_on_tx_done = true;
3933 				}
3934 			}
3935 
3936 			slgt_irq_off(info, IRQ_TXDATA);
3937 			slgt_irq_on(info, IRQ_TXUNDER + IRQ_TXIDLE);
3938 			/* clear tx idle and underrun status bits */
3939 			wr_reg16(info, SSR, (unsigned short)(IRQ_TXIDLE + IRQ_TXUNDER));
3940 		} else {
3941 			slgt_irq_off(info, IRQ_TXDATA);
3942 			slgt_irq_on(info, IRQ_TXIDLE);
3943 			/* clear tx idle status bit */
3944 			wr_reg16(info, SSR, IRQ_TXIDLE);
3945 		}
3946 		/* set 1st descriptor address and start DMA */
3947 		wr_reg32(info, TDDAR, info->tbufs[info->tbuf_start].pdesc);
3948 		wr_reg32(info, TDCSR, BIT2 + BIT0);
3949 		info->tx_active = true;
3950 	}
3951 }
3952 
3953 static void tx_stop(struct slgt_info *info)
3954 {
3955 	unsigned short val;
3956 
3957 	del_timer(&info->tx_timer);
3958 
3959 	tdma_reset(info);
3960 
3961 	/* reset and disable transmitter */
3962 	val = rd_reg16(info, TCR) & ~BIT1;          /* clear enable bit */
3963 	wr_reg16(info, TCR, (unsigned short)(val | BIT2)); /* set reset bit */
3964 
3965 	slgt_irq_off(info, IRQ_TXDATA + IRQ_TXIDLE + IRQ_TXUNDER);
3966 
3967 	/* clear tx idle and underrun status bit */
3968 	wr_reg16(info, SSR, (unsigned short)(IRQ_TXIDLE + IRQ_TXUNDER));
3969 
3970 	reset_tbufs(info);
3971 
3972 	info->tx_enabled = false;
3973 	info->tx_active = false;
3974 }
3975 
3976 static void reset_port(struct slgt_info *info)
3977 {
3978 	if (!info->reg_addr)
3979 		return;
3980 
3981 	tx_stop(info);
3982 	rx_stop(info);
3983 
3984 	info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
3985 	set_gtsignals(info);
3986 
3987 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
3988 }
3989 
3990 static void reset_adapter(struct slgt_info *info)
3991 {
3992 	int i;
3993 	for (i=0; i < info->port_count; ++i) {
3994 		if (info->port_array[i])
3995 			reset_port(info->port_array[i]);
3996 	}
3997 }
3998 
3999 static void async_mode(struct slgt_info *info)
4000 {
4001   	unsigned short val;
4002 
4003 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4004 	tx_stop(info);
4005 	rx_stop(info);
4006 
4007 	/* TCR (tx control)
4008 	 *
4009 	 * 15..13  mode, 010=async
4010 	 * 12..10  encoding, 000=NRZ
4011 	 * 09      parity enable
4012 	 * 08      1=odd parity, 0=even parity
4013 	 * 07      1=RTS driver control
4014 	 * 06      1=break enable
4015 	 * 05..04  character length
4016 	 *         00=5 bits
4017 	 *         01=6 bits
4018 	 *         10=7 bits
4019 	 *         11=8 bits
4020 	 * 03      0=1 stop bit, 1=2 stop bits
4021 	 * 02      reset
4022 	 * 01      enable
4023 	 * 00      auto-CTS enable
4024 	 */
4025 	val = 0x4000;
4026 
4027 	if (info->if_mode & MGSL_INTERFACE_RTS_EN)
4028 		val |= BIT7;
4029 
4030 	if (info->params.parity != ASYNC_PARITY_NONE) {
4031 		val |= BIT9;
4032 		if (info->params.parity == ASYNC_PARITY_ODD)
4033 			val |= BIT8;
4034 	}
4035 
4036 	switch (info->params.data_bits)
4037 	{
4038 	case 6: val |= BIT4; break;
4039 	case 7: val |= BIT5; break;
4040 	case 8: val |= BIT5 + BIT4; break;
4041 	}
4042 
4043 	if (info->params.stop_bits != 1)
4044 		val |= BIT3;
4045 
4046 	if (info->params.flags & HDLC_FLAG_AUTO_CTS)
4047 		val |= BIT0;
4048 
4049 	wr_reg16(info, TCR, val);
4050 
4051 	/* RCR (rx control)
4052 	 *
4053 	 * 15..13  mode, 010=async
4054 	 * 12..10  encoding, 000=NRZ
4055 	 * 09      parity enable
4056 	 * 08      1=odd parity, 0=even parity
4057 	 * 07..06  reserved, must be 0
4058 	 * 05..04  character length
4059 	 *         00=5 bits
4060 	 *         01=6 bits
4061 	 *         10=7 bits
4062 	 *         11=8 bits
4063 	 * 03      reserved, must be zero
4064 	 * 02      reset
4065 	 * 01      enable
4066 	 * 00      auto-DCD enable
4067 	 */
4068 	val = 0x4000;
4069 
4070 	if (info->params.parity != ASYNC_PARITY_NONE) {
4071 		val |= BIT9;
4072 		if (info->params.parity == ASYNC_PARITY_ODD)
4073 			val |= BIT8;
4074 	}
4075 
4076 	switch (info->params.data_bits)
4077 	{
4078 	case 6: val |= BIT4; break;
4079 	case 7: val |= BIT5; break;
4080 	case 8: val |= BIT5 + BIT4; break;
4081 	}
4082 
4083 	if (info->params.flags & HDLC_FLAG_AUTO_DCD)
4084 		val |= BIT0;
4085 
4086 	wr_reg16(info, RCR, val);
4087 
4088 	/* CCR (clock control)
4089 	 *
4090 	 * 07..05  011 = tx clock source is BRG/16
4091 	 * 04..02  010 = rx clock source is BRG
4092 	 * 01      0 = auxclk disabled
4093 	 * 00      1 = BRG enabled
4094 	 *
4095 	 * 0110 1001
4096 	 */
4097 	wr_reg8(info, CCR, 0x69);
4098 
4099 	msc_set_vcr(info);
4100 
4101 	/* SCR (serial control)
4102 	 *
4103 	 * 15  1=tx req on FIFO half empty
4104 	 * 14  1=rx req on FIFO half full
4105 	 * 13  tx data  IRQ enable
4106 	 * 12  tx idle  IRQ enable
4107 	 * 11  rx break on IRQ enable
4108 	 * 10  rx data  IRQ enable
4109 	 * 09  rx break off IRQ enable
4110 	 * 08  overrun  IRQ enable
4111 	 * 07  DSR      IRQ enable
4112 	 * 06  CTS      IRQ enable
4113 	 * 05  DCD      IRQ enable
4114 	 * 04  RI       IRQ enable
4115 	 * 03  0=16x sampling, 1=8x sampling
4116 	 * 02  1=txd->rxd internal loopback enable
4117 	 * 01  reserved, must be zero
4118 	 * 00  1=master IRQ enable
4119 	 */
4120 	val = BIT15 + BIT14 + BIT0;
4121 	/* JCR[8] : 1 = x8 async mode feature available */
4122 	if ((rd_reg32(info, JCR) & BIT8) && info->params.data_rate &&
4123 	    ((info->base_clock < (info->params.data_rate * 16)) ||
4124 	     (info->base_clock % (info->params.data_rate * 16)))) {
4125 		/* use 8x sampling */
4126 		val |= BIT3;
4127 		set_rate(info, info->params.data_rate * 8);
4128 	} else {
4129 		/* use 16x sampling */
4130 		set_rate(info, info->params.data_rate * 16);
4131 	}
4132 	wr_reg16(info, SCR, val);
4133 
4134 	slgt_irq_on(info, IRQ_RXBREAK | IRQ_RXOVER);
4135 
4136 	if (info->params.loopback)
4137 		enable_loopback(info);
4138 }
4139 
4140 static void sync_mode(struct slgt_info *info)
4141 {
4142 	unsigned short val;
4143 
4144 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4145 	tx_stop(info);
4146 	rx_stop(info);
4147 
4148 	/* TCR (tx control)
4149 	 *
4150 	 * 15..13  mode
4151 	 *         000=HDLC/SDLC
4152 	 *         001=raw bit synchronous
4153 	 *         010=asynchronous/isochronous
4154 	 *         011=monosync byte synchronous
4155 	 *         100=bisync byte synchronous
4156 	 *         101=xsync byte synchronous
4157 	 * 12..10  encoding
4158 	 * 09      CRC enable
4159 	 * 08      CRC32
4160 	 * 07      1=RTS driver control
4161 	 * 06      preamble enable
4162 	 * 05..04  preamble length
4163 	 * 03      share open/close flag
4164 	 * 02      reset
4165 	 * 01      enable
4166 	 * 00      auto-CTS enable
4167 	 */
4168 	val = BIT2;
4169 
4170 	switch(info->params.mode) {
4171 	case MGSL_MODE_XSYNC:
4172 		val |= BIT15 + BIT13;
4173 		break;
4174 	case MGSL_MODE_MONOSYNC: val |= BIT14 + BIT13; break;
4175 	case MGSL_MODE_BISYNC:   val |= BIT15; break;
4176 	case MGSL_MODE_RAW:      val |= BIT13; break;
4177 	}
4178 	if (info->if_mode & MGSL_INTERFACE_RTS_EN)
4179 		val |= BIT7;
4180 
4181 	switch(info->params.encoding)
4182 	{
4183 	case HDLC_ENCODING_NRZB:          val |= BIT10; break;
4184 	case HDLC_ENCODING_NRZI_MARK:     val |= BIT11; break;
4185 	case HDLC_ENCODING_NRZI:          val |= BIT11 + BIT10; break;
4186 	case HDLC_ENCODING_BIPHASE_MARK:  val |= BIT12; break;
4187 	case HDLC_ENCODING_BIPHASE_SPACE: val |= BIT12 + BIT10; break;
4188 	case HDLC_ENCODING_BIPHASE_LEVEL: val |= BIT12 + BIT11; break;
4189 	case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: val |= BIT12 + BIT11 + BIT10; break;
4190 	}
4191 
4192 	switch (info->params.crc_type & HDLC_CRC_MASK)
4193 	{
4194 	case HDLC_CRC_16_CCITT: val |= BIT9; break;
4195 	case HDLC_CRC_32_CCITT: val |= BIT9 + BIT8; break;
4196 	}
4197 
4198 	if (info->params.preamble != HDLC_PREAMBLE_PATTERN_NONE)
4199 		val |= BIT6;
4200 
4201 	switch (info->params.preamble_length)
4202 	{
4203 	case HDLC_PREAMBLE_LENGTH_16BITS: val |= BIT5; break;
4204 	case HDLC_PREAMBLE_LENGTH_32BITS: val |= BIT4; break;
4205 	case HDLC_PREAMBLE_LENGTH_64BITS: val |= BIT5 + BIT4; break;
4206 	}
4207 
4208 	if (info->params.flags & HDLC_FLAG_AUTO_CTS)
4209 		val |= BIT0;
4210 
4211 	wr_reg16(info, TCR, val);
4212 
4213 	/* TPR (transmit preamble) */
4214 
4215 	switch (info->params.preamble)
4216 	{
4217 	case HDLC_PREAMBLE_PATTERN_FLAGS: val = 0x7e; break;
4218 	case HDLC_PREAMBLE_PATTERN_ONES:  val = 0xff; break;
4219 	case HDLC_PREAMBLE_PATTERN_ZEROS: val = 0x00; break;
4220 	case HDLC_PREAMBLE_PATTERN_10:    val = 0x55; break;
4221 	case HDLC_PREAMBLE_PATTERN_01:    val = 0xaa; break;
4222 	default:                          val = 0x7e; break;
4223 	}
4224 	wr_reg8(info, TPR, (unsigned char)val);
4225 
4226 	/* RCR (rx control)
4227 	 *
4228 	 * 15..13  mode
4229 	 *         000=HDLC/SDLC
4230 	 *         001=raw bit synchronous
4231 	 *         010=asynchronous/isochronous
4232 	 *         011=monosync byte synchronous
4233 	 *         100=bisync byte synchronous
4234 	 *         101=xsync byte synchronous
4235 	 * 12..10  encoding
4236 	 * 09      CRC enable
4237 	 * 08      CRC32
4238 	 * 07..03  reserved, must be 0
4239 	 * 02      reset
4240 	 * 01      enable
4241 	 * 00      auto-DCD enable
4242 	 */
4243 	val = 0;
4244 
4245 	switch(info->params.mode) {
4246 	case MGSL_MODE_XSYNC:
4247 		val |= BIT15 + BIT13;
4248 		break;
4249 	case MGSL_MODE_MONOSYNC: val |= BIT14 + BIT13; break;
4250 	case MGSL_MODE_BISYNC:   val |= BIT15; break;
4251 	case MGSL_MODE_RAW:      val |= BIT13; break;
4252 	}
4253 
4254 	switch(info->params.encoding)
4255 	{
4256 	case HDLC_ENCODING_NRZB:          val |= BIT10; break;
4257 	case HDLC_ENCODING_NRZI_MARK:     val |= BIT11; break;
4258 	case HDLC_ENCODING_NRZI:          val |= BIT11 + BIT10; break;
4259 	case HDLC_ENCODING_BIPHASE_MARK:  val |= BIT12; break;
4260 	case HDLC_ENCODING_BIPHASE_SPACE: val |= BIT12 + BIT10; break;
4261 	case HDLC_ENCODING_BIPHASE_LEVEL: val |= BIT12 + BIT11; break;
4262 	case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: val |= BIT12 + BIT11 + BIT10; break;
4263 	}
4264 
4265 	switch (info->params.crc_type & HDLC_CRC_MASK)
4266 	{
4267 	case HDLC_CRC_16_CCITT: val |= BIT9; break;
4268 	case HDLC_CRC_32_CCITT: val |= BIT9 + BIT8; break;
4269 	}
4270 
4271 	if (info->params.flags & HDLC_FLAG_AUTO_DCD)
4272 		val |= BIT0;
4273 
4274 	wr_reg16(info, RCR, val);
4275 
4276 	/* CCR (clock control)
4277 	 *
4278 	 * 07..05  tx clock source
4279 	 * 04..02  rx clock source
4280 	 * 01      auxclk enable
4281 	 * 00      BRG enable
4282 	 */
4283 	val = 0;
4284 
4285 	if (info->params.flags & HDLC_FLAG_TXC_BRG)
4286 	{
4287 		// when RxC source is DPLL, BRG generates 16X DPLL
4288 		// reference clock, so take TxC from BRG/16 to get
4289 		// transmit clock at actual data rate
4290 		if (info->params.flags & HDLC_FLAG_RXC_DPLL)
4291 			val |= BIT6 + BIT5;	/* 011, txclk = BRG/16 */
4292 		else
4293 			val |= BIT6;	/* 010, txclk = BRG */
4294 	}
4295 	else if (info->params.flags & HDLC_FLAG_TXC_DPLL)
4296 		val |= BIT7;	/* 100, txclk = DPLL Input */
4297 	else if (info->params.flags & HDLC_FLAG_TXC_RXCPIN)
4298 		val |= BIT5;	/* 001, txclk = RXC Input */
4299 
4300 	if (info->params.flags & HDLC_FLAG_RXC_BRG)
4301 		val |= BIT3;	/* 010, rxclk = BRG */
4302 	else if (info->params.flags & HDLC_FLAG_RXC_DPLL)
4303 		val |= BIT4;	/* 100, rxclk = DPLL */
4304 	else if (info->params.flags & HDLC_FLAG_RXC_TXCPIN)
4305 		val |= BIT2;	/* 001, rxclk = TXC Input */
4306 
4307 	if (info->params.clock_speed)
4308 		val |= BIT1 + BIT0;
4309 
4310 	wr_reg8(info, CCR, (unsigned char)val);
4311 
4312 	if (info->params.flags & (HDLC_FLAG_TXC_DPLL + HDLC_FLAG_RXC_DPLL))
4313 	{
4314 		// program DPLL mode
4315 		switch(info->params.encoding)
4316 		{
4317 		case HDLC_ENCODING_BIPHASE_MARK:
4318 		case HDLC_ENCODING_BIPHASE_SPACE:
4319 			val = BIT7; break;
4320 		case HDLC_ENCODING_BIPHASE_LEVEL:
4321 		case HDLC_ENCODING_DIFF_BIPHASE_LEVEL:
4322 			val = BIT7 + BIT6; break;
4323 		default: val = BIT6;	// NRZ encodings
4324 		}
4325 		wr_reg16(info, RCR, (unsigned short)(rd_reg16(info, RCR) | val));
4326 
4327 		// DPLL requires a 16X reference clock from BRG
4328 		set_rate(info, info->params.clock_speed * 16);
4329 	}
4330 	else
4331 		set_rate(info, info->params.clock_speed);
4332 
4333 	tx_set_idle(info);
4334 
4335 	msc_set_vcr(info);
4336 
4337 	/* SCR (serial control)
4338 	 *
4339 	 * 15  1=tx req on FIFO half empty
4340 	 * 14  1=rx req on FIFO half full
4341 	 * 13  tx data  IRQ enable
4342 	 * 12  tx idle  IRQ enable
4343 	 * 11  underrun IRQ enable
4344 	 * 10  rx data  IRQ enable
4345 	 * 09  rx idle  IRQ enable
4346 	 * 08  overrun  IRQ enable
4347 	 * 07  DSR      IRQ enable
4348 	 * 06  CTS      IRQ enable
4349 	 * 05  DCD      IRQ enable
4350 	 * 04  RI       IRQ enable
4351 	 * 03  reserved, must be zero
4352 	 * 02  1=txd->rxd internal loopback enable
4353 	 * 01  reserved, must be zero
4354 	 * 00  1=master IRQ enable
4355 	 */
4356 	wr_reg16(info, SCR, BIT15 + BIT14 + BIT0);
4357 
4358 	if (info->params.loopback)
4359 		enable_loopback(info);
4360 }
4361 
4362 /*
4363  *  set transmit idle mode
4364  */
4365 static void tx_set_idle(struct slgt_info *info)
4366 {
4367 	unsigned char val;
4368 	unsigned short tcr;
4369 
4370 	/* if preamble enabled (tcr[6] == 1) then tx idle size = 8 bits
4371 	 * else tcr[5:4] = tx idle size: 00 = 8 bits, 01 = 16 bits
4372 	 */
4373 	tcr = rd_reg16(info, TCR);
4374 	if (info->idle_mode & HDLC_TXIDLE_CUSTOM_16) {
4375 		/* disable preamble, set idle size to 16 bits */
4376 		tcr = (tcr & ~(BIT6 + BIT5)) | BIT4;
4377 		/* MSB of 16 bit idle specified in tx preamble register (TPR) */
4378 		wr_reg8(info, TPR, (unsigned char)((info->idle_mode >> 8) & 0xff));
4379 	} else if (!(tcr & BIT6)) {
4380 		/* preamble is disabled, set idle size to 8 bits */
4381 		tcr &= ~(BIT5 + BIT4);
4382 	}
4383 	wr_reg16(info, TCR, tcr);
4384 
4385 	if (info->idle_mode & (HDLC_TXIDLE_CUSTOM_8 | HDLC_TXIDLE_CUSTOM_16)) {
4386 		/* LSB of custom tx idle specified in tx idle register */
4387 		val = (unsigned char)(info->idle_mode & 0xff);
4388 	} else {
4389 		/* standard 8 bit idle patterns */
4390 		switch(info->idle_mode)
4391 		{
4392 		case HDLC_TXIDLE_FLAGS:          val = 0x7e; break;
4393 		case HDLC_TXIDLE_ALT_ZEROS_ONES:
4394 		case HDLC_TXIDLE_ALT_MARK_SPACE: val = 0xaa; break;
4395 		case HDLC_TXIDLE_ZEROS:
4396 		case HDLC_TXIDLE_SPACE:          val = 0x00; break;
4397 		default:                         val = 0xff;
4398 		}
4399 	}
4400 
4401 	wr_reg8(info, TIR, val);
4402 }
4403 
4404 /*
4405  * get state of V24 status (input) signals
4406  */
4407 static void get_gtsignals(struct slgt_info *info)
4408 {
4409 	unsigned short status = rd_reg16(info, SSR);
4410 
4411 	/* clear all serial signals except RTS and DTR */
4412 	info->signals &= SerialSignal_RTS | SerialSignal_DTR;
4413 
4414 	if (status & BIT3)
4415 		info->signals |= SerialSignal_DSR;
4416 	if (status & BIT2)
4417 		info->signals |= SerialSignal_CTS;
4418 	if (status & BIT1)
4419 		info->signals |= SerialSignal_DCD;
4420 	if (status & BIT0)
4421 		info->signals |= SerialSignal_RI;
4422 }
4423 
4424 /*
4425  * set V.24 Control Register based on current configuration
4426  */
4427 static void msc_set_vcr(struct slgt_info *info)
4428 {
4429 	unsigned char val = 0;
4430 
4431 	/* VCR (V.24 control)
4432 	 *
4433 	 * 07..04  serial IF select
4434 	 * 03      DTR
4435 	 * 02      RTS
4436 	 * 01      LL
4437 	 * 00      RL
4438 	 */
4439 
4440 	switch(info->if_mode & MGSL_INTERFACE_MASK)
4441 	{
4442 	case MGSL_INTERFACE_RS232:
4443 		val |= BIT5; /* 0010 */
4444 		break;
4445 	case MGSL_INTERFACE_V35:
4446 		val |= BIT7 + BIT6 + BIT5; /* 1110 */
4447 		break;
4448 	case MGSL_INTERFACE_RS422:
4449 		val |= BIT6; /* 0100 */
4450 		break;
4451 	}
4452 
4453 	if (info->if_mode & MGSL_INTERFACE_MSB_FIRST)
4454 		val |= BIT4;
4455 	if (info->signals & SerialSignal_DTR)
4456 		val |= BIT3;
4457 	if (info->signals & SerialSignal_RTS)
4458 		val |= BIT2;
4459 	if (info->if_mode & MGSL_INTERFACE_LL)
4460 		val |= BIT1;
4461 	if (info->if_mode & MGSL_INTERFACE_RL)
4462 		val |= BIT0;
4463 	wr_reg8(info, VCR, val);
4464 }
4465 
4466 /*
4467  * set state of V24 control (output) signals
4468  */
4469 static void set_gtsignals(struct slgt_info *info)
4470 {
4471 	unsigned char val = rd_reg8(info, VCR);
4472 	if (info->signals & SerialSignal_DTR)
4473 		val |= BIT3;
4474 	else
4475 		val &= ~BIT3;
4476 	if (info->signals & SerialSignal_RTS)
4477 		val |= BIT2;
4478 	else
4479 		val &= ~BIT2;
4480 	wr_reg8(info, VCR, val);
4481 }
4482 
4483 /*
4484  * free range of receive DMA buffers (i to last)
4485  */
4486 static void free_rbufs(struct slgt_info *info, unsigned int i, unsigned int last)
4487 {
4488 	int done = 0;
4489 
4490 	while(!done) {
4491 		/* reset current buffer for reuse */
4492 		info->rbufs[i].status = 0;
4493 		set_desc_count(info->rbufs[i], info->rbuf_fill_level);
4494 		if (i == last)
4495 			done = 1;
4496 		if (++i == info->rbuf_count)
4497 			i = 0;
4498 	}
4499 	info->rbuf_current = i;
4500 }
4501 
4502 /*
4503  * mark all receive DMA buffers as free
4504  */
4505 static void reset_rbufs(struct slgt_info *info)
4506 {
4507 	free_rbufs(info, 0, info->rbuf_count - 1);
4508 	info->rbuf_fill_index = 0;
4509 	info->rbuf_fill_count = 0;
4510 }
4511 
4512 /*
4513  * pass receive HDLC frame to upper layer
4514  *
4515  * return true if frame available, otherwise false
4516  */
4517 static bool rx_get_frame(struct slgt_info *info)
4518 {
4519 	unsigned int start, end;
4520 	unsigned short status;
4521 	unsigned int framesize = 0;
4522 	unsigned long flags;
4523 	struct tty_struct *tty = info->port.tty;
4524 	unsigned char addr_field = 0xff;
4525 	unsigned int crc_size = 0;
4526 
4527 	switch (info->params.crc_type & HDLC_CRC_MASK) {
4528 	case HDLC_CRC_16_CCITT: crc_size = 2; break;
4529 	case HDLC_CRC_32_CCITT: crc_size = 4; break;
4530 	}
4531 
4532 check_again:
4533 
4534 	framesize = 0;
4535 	addr_field = 0xff;
4536 	start = end = info->rbuf_current;
4537 
4538 	for (;;) {
4539 		if (!desc_complete(info->rbufs[end]))
4540 			goto cleanup;
4541 
4542 		if (framesize == 0 && info->params.addr_filter != 0xff)
4543 			addr_field = info->rbufs[end].buf[0];
4544 
4545 		framesize += desc_count(info->rbufs[end]);
4546 
4547 		if (desc_eof(info->rbufs[end]))
4548 			break;
4549 
4550 		if (++end == info->rbuf_count)
4551 			end = 0;
4552 
4553 		if (end == info->rbuf_current) {
4554 			if (info->rx_enabled){
4555 				spin_lock_irqsave(&info->lock,flags);
4556 				rx_start(info);
4557 				spin_unlock_irqrestore(&info->lock,flags);
4558 			}
4559 			goto cleanup;
4560 		}
4561 	}
4562 
4563 	/* status
4564 	 *
4565 	 * 15      buffer complete
4566 	 * 14..06  reserved
4567 	 * 05..04  residue
4568 	 * 02      eof (end of frame)
4569 	 * 01      CRC error
4570 	 * 00      abort
4571 	 */
4572 	status = desc_status(info->rbufs[end]);
4573 
4574 	/* ignore CRC bit if not using CRC (bit is undefined) */
4575 	if ((info->params.crc_type & HDLC_CRC_MASK) == HDLC_CRC_NONE)
4576 		status &= ~BIT1;
4577 
4578 	if (framesize == 0 ||
4579 		 (addr_field != 0xff && addr_field != info->params.addr_filter)) {
4580 		free_rbufs(info, start, end);
4581 		goto check_again;
4582 	}
4583 
4584 	if (framesize < (2 + crc_size) || status & BIT0) {
4585 		info->icount.rxshort++;
4586 		framesize = 0;
4587 	} else if (status & BIT1) {
4588 		info->icount.rxcrc++;
4589 		if (!(info->params.crc_type & HDLC_CRC_RETURN_EX))
4590 			framesize = 0;
4591 	}
4592 
4593 #if SYNCLINK_GENERIC_HDLC
4594 	if (framesize == 0) {
4595 		info->netdev->stats.rx_errors++;
4596 		info->netdev->stats.rx_frame_errors++;
4597 	}
4598 #endif
4599 
4600 	DBGBH(("%s rx frame status=%04X size=%d\n",
4601 		info->device_name, status, framesize));
4602 	DBGDATA(info, info->rbufs[start].buf, min_t(int, framesize, info->rbuf_fill_level), "rx");
4603 
4604 	if (framesize) {
4605 		if (!(info->params.crc_type & HDLC_CRC_RETURN_EX)) {
4606 			framesize -= crc_size;
4607 			crc_size = 0;
4608 		}
4609 
4610 		if (framesize > info->max_frame_size + crc_size)
4611 			info->icount.rxlong++;
4612 		else {
4613 			/* copy dma buffer(s) to contiguous temp buffer */
4614 			int copy_count = framesize;
4615 			int i = start;
4616 			unsigned char *p = info->tmp_rbuf;
4617 			info->tmp_rbuf_count = framesize;
4618 
4619 			info->icount.rxok++;
4620 
4621 			while(copy_count) {
4622 				int partial_count = min_t(int, copy_count, info->rbuf_fill_level);
4623 				memcpy(p, info->rbufs[i].buf, partial_count);
4624 				p += partial_count;
4625 				copy_count -= partial_count;
4626 				if (++i == info->rbuf_count)
4627 					i = 0;
4628 			}
4629 
4630 			if (info->params.crc_type & HDLC_CRC_RETURN_EX) {
4631 				*p = (status & BIT1) ? RX_CRC_ERROR : RX_OK;
4632 				framesize++;
4633 			}
4634 
4635 #if SYNCLINK_GENERIC_HDLC
4636 			if (info->netcount)
4637 				hdlcdev_rx(info,info->tmp_rbuf, framesize);
4638 			else
4639 #endif
4640 				ldisc_receive_buf(tty, info->tmp_rbuf, NULL,
4641 						  framesize);
4642 		}
4643 	}
4644 	free_rbufs(info, start, end);
4645 	return true;
4646 
4647 cleanup:
4648 	return false;
4649 }
4650 
4651 /*
4652  * pass receive buffer (RAW synchronous mode) to tty layer
4653  * return true if buffer available, otherwise false
4654  */
4655 static bool rx_get_buf(struct slgt_info *info)
4656 {
4657 	unsigned int i = info->rbuf_current;
4658 	unsigned int count;
4659 
4660 	if (!desc_complete(info->rbufs[i]))
4661 		return false;
4662 	count = desc_count(info->rbufs[i]);
4663 	switch(info->params.mode) {
4664 	case MGSL_MODE_MONOSYNC:
4665 	case MGSL_MODE_BISYNC:
4666 	case MGSL_MODE_XSYNC:
4667 		/* ignore residue in byte synchronous modes */
4668 		if (desc_residue(info->rbufs[i]))
4669 			count--;
4670 		break;
4671 	}
4672 	DBGDATA(info, info->rbufs[i].buf, count, "rx");
4673 	DBGINFO(("rx_get_buf size=%d\n", count));
4674 	if (count)
4675 		ldisc_receive_buf(info->port.tty, info->rbufs[i].buf, NULL,
4676 				  count);
4677 	free_rbufs(info, i, i);
4678 	return true;
4679 }
4680 
4681 static void reset_tbufs(struct slgt_info *info)
4682 {
4683 	unsigned int i;
4684 	info->tbuf_current = 0;
4685 	for (i=0 ; i < info->tbuf_count ; i++) {
4686 		info->tbufs[i].status = 0;
4687 		info->tbufs[i].count  = 0;
4688 	}
4689 }
4690 
4691 /*
4692  * return number of free transmit DMA buffers
4693  */
4694 static unsigned int free_tbuf_count(struct slgt_info *info)
4695 {
4696 	unsigned int count = 0;
4697 	unsigned int i = info->tbuf_current;
4698 
4699 	do
4700 	{
4701 		if (desc_count(info->tbufs[i]))
4702 			break; /* buffer in use */
4703 		++count;
4704 		if (++i == info->tbuf_count)
4705 			i=0;
4706 	} while (i != info->tbuf_current);
4707 
4708 	/* if tx DMA active, last zero count buffer is in use */
4709 	if (count && (rd_reg32(info, TDCSR) & BIT0))
4710 		--count;
4711 
4712 	return count;
4713 }
4714 
4715 /*
4716  * return number of bytes in unsent transmit DMA buffers
4717  * and the serial controller tx FIFO
4718  */
4719 static unsigned int tbuf_bytes(struct slgt_info *info)
4720 {
4721 	unsigned int total_count = 0;
4722 	unsigned int i = info->tbuf_current;
4723 	unsigned int reg_value;
4724 	unsigned int count;
4725 	unsigned int active_buf_count = 0;
4726 
4727 	/*
4728 	 * Add descriptor counts for all tx DMA buffers.
4729 	 * If count is zero (cleared by DMA controller after read),
4730 	 * the buffer is complete or is actively being read from.
4731 	 *
4732 	 * Record buf_count of last buffer with zero count starting
4733 	 * from current ring position. buf_count is mirror
4734 	 * copy of count and is not cleared by serial controller.
4735 	 * If DMA controller is active, that buffer is actively
4736 	 * being read so add to total.
4737 	 */
4738 	do {
4739 		count = desc_count(info->tbufs[i]);
4740 		if (count)
4741 			total_count += count;
4742 		else if (!total_count)
4743 			active_buf_count = info->tbufs[i].buf_count;
4744 		if (++i == info->tbuf_count)
4745 			i = 0;
4746 	} while (i != info->tbuf_current);
4747 
4748 	/* read tx DMA status register */
4749 	reg_value = rd_reg32(info, TDCSR);
4750 
4751 	/* if tx DMA active, last zero count buffer is in use */
4752 	if (reg_value & BIT0)
4753 		total_count += active_buf_count;
4754 
4755 	/* add tx FIFO count = reg_value[15..8] */
4756 	total_count += (reg_value >> 8) & 0xff;
4757 
4758 	/* if transmitter active add one byte for shift register */
4759 	if (info->tx_active)
4760 		total_count++;
4761 
4762 	return total_count;
4763 }
4764 
4765 /*
4766  * load data into transmit DMA buffer ring and start transmitter if needed
4767  * return true if data accepted, otherwise false (buffers full)
4768  */
4769 static bool tx_load(struct slgt_info *info, const u8 *buf, unsigned int size)
4770 {
4771 	unsigned short count;
4772 	unsigned int i;
4773 	struct slgt_desc *d;
4774 
4775 	/* check required buffer space */
4776 	if (DIV_ROUND_UP(size, DMABUFSIZE) > free_tbuf_count(info))
4777 		return false;
4778 
4779 	DBGDATA(info, buf, size, "tx");
4780 
4781 	/*
4782 	 * copy data to one or more DMA buffers in circular ring
4783 	 * tbuf_start   = first buffer for this data
4784 	 * tbuf_current = next free buffer
4785 	 *
4786 	 * Copy all data before making data visible to DMA controller by
4787 	 * setting descriptor count of the first buffer.
4788 	 * This prevents an active DMA controller from reading the first DMA
4789 	 * buffers of a frame and stopping before the final buffers are filled.
4790 	 */
4791 
4792 	info->tbuf_start = i = info->tbuf_current;
4793 
4794 	while (size) {
4795 		d = &info->tbufs[i];
4796 
4797 		count = (unsigned short)((size > DMABUFSIZE) ? DMABUFSIZE : size);
4798 		memcpy(d->buf, buf, count);
4799 
4800 		size -= count;
4801 		buf  += count;
4802 
4803 		/*
4804 		 * set EOF bit for last buffer of HDLC frame or
4805 		 * for every buffer in raw mode
4806 		 */
4807 		if ((!size && info->params.mode == MGSL_MODE_HDLC) ||
4808 		    info->params.mode == MGSL_MODE_RAW)
4809 			set_desc_eof(*d, 1);
4810 		else
4811 			set_desc_eof(*d, 0);
4812 
4813 		/* set descriptor count for all but first buffer */
4814 		if (i != info->tbuf_start)
4815 			set_desc_count(*d, count);
4816 		d->buf_count = count;
4817 
4818 		if (++i == info->tbuf_count)
4819 			i = 0;
4820 	}
4821 
4822 	info->tbuf_current = i;
4823 
4824 	/* set first buffer count to make new data visible to DMA controller */
4825 	d = &info->tbufs[info->tbuf_start];
4826 	set_desc_count(*d, d->buf_count);
4827 
4828 	/* start transmitter if needed and update transmit timeout */
4829 	if (!info->tx_active)
4830 		tx_start(info);
4831 	update_tx_timer(info);
4832 
4833 	return true;
4834 }
4835 
4836 static int register_test(struct slgt_info *info)
4837 {
4838 	static unsigned short patterns[] =
4839 		{0x0000, 0xffff, 0xaaaa, 0x5555, 0x6969, 0x9696};
4840 	static unsigned int count = ARRAY_SIZE(patterns);
4841 	unsigned int i;
4842 	int rc = 0;
4843 
4844 	for (i=0 ; i < count ; i++) {
4845 		wr_reg16(info, TIR, patterns[i]);
4846 		wr_reg16(info, BDR, patterns[(i+1)%count]);
4847 		if ((rd_reg16(info, TIR) != patterns[i]) ||
4848 		    (rd_reg16(info, BDR) != patterns[(i+1)%count])) {
4849 			rc = -ENODEV;
4850 			break;
4851 		}
4852 	}
4853 	info->gpio_present = (rd_reg32(info, JCR) & BIT5) ? 1 : 0;
4854 	info->init_error = rc ? 0 : DiagStatus_AddressFailure;
4855 	return rc;
4856 }
4857 
4858 static int irq_test(struct slgt_info *info)
4859 {
4860 	unsigned long timeout;
4861 	unsigned long flags;
4862 	struct tty_struct *oldtty = info->port.tty;
4863 	u32 speed = info->params.data_rate;
4864 
4865 	info->params.data_rate = 921600;
4866 	info->port.tty = NULL;
4867 
4868 	spin_lock_irqsave(&info->lock, flags);
4869 	async_mode(info);
4870 	slgt_irq_on(info, IRQ_TXIDLE);
4871 
4872 	/* enable transmitter */
4873 	wr_reg16(info, TCR,
4874 		(unsigned short)(rd_reg16(info, TCR) | BIT1));
4875 
4876 	/* write one byte and wait for tx idle */
4877 	wr_reg16(info, TDR, 0);
4878 
4879 	/* assume failure */
4880 	info->init_error = DiagStatus_IrqFailure;
4881 	info->irq_occurred = false;
4882 
4883 	spin_unlock_irqrestore(&info->lock, flags);
4884 
4885 	timeout=100;
4886 	while(timeout-- && !info->irq_occurred)
4887 		msleep_interruptible(10);
4888 
4889 	spin_lock_irqsave(&info->lock,flags);
4890 	reset_port(info);
4891 	spin_unlock_irqrestore(&info->lock,flags);
4892 
4893 	info->params.data_rate = speed;
4894 	info->port.tty = oldtty;
4895 
4896 	info->init_error = info->irq_occurred ? 0 : DiagStatus_IrqFailure;
4897 	return info->irq_occurred ? 0 : -ENODEV;
4898 }
4899 
4900 static int loopback_test_rx(struct slgt_info *info)
4901 {
4902 	unsigned char *src, *dest;
4903 	int count;
4904 
4905 	if (desc_complete(info->rbufs[0])) {
4906 		count = desc_count(info->rbufs[0]);
4907 		src   = info->rbufs[0].buf;
4908 		dest  = info->tmp_rbuf;
4909 
4910 		for( ; count ; count-=2, src+=2) {
4911 			/* src=data byte (src+1)=status byte */
4912 			if (!(*(src+1) & (BIT9 + BIT8))) {
4913 				*dest = *src;
4914 				dest++;
4915 				info->tmp_rbuf_count++;
4916 			}
4917 		}
4918 		DBGDATA(info, info->tmp_rbuf, info->tmp_rbuf_count, "rx");
4919 		return 1;
4920 	}
4921 	return 0;
4922 }
4923 
4924 static int loopback_test(struct slgt_info *info)
4925 {
4926 #define TESTFRAMESIZE 20
4927 
4928 	unsigned long timeout;
4929 	u16 count;
4930 	unsigned char buf[TESTFRAMESIZE];
4931 	int rc = -ENODEV;
4932 	unsigned long flags;
4933 
4934 	struct tty_struct *oldtty = info->port.tty;
4935 	MGSL_PARAMS params;
4936 
4937 	memcpy(&params, &info->params, sizeof(params));
4938 
4939 	info->params.mode = MGSL_MODE_ASYNC;
4940 	info->params.data_rate = 921600;
4941 	info->params.loopback = 1;
4942 	info->port.tty = NULL;
4943 
4944 	/* build and send transmit frame */
4945 	for (count = 0; count < TESTFRAMESIZE; ++count)
4946 		buf[count] = (unsigned char)count;
4947 
4948 	info->tmp_rbuf_count = 0;
4949 	memset(info->tmp_rbuf, 0, TESTFRAMESIZE);
4950 
4951 	/* program hardware for HDLC and enabled receiver */
4952 	spin_lock_irqsave(&info->lock,flags);
4953 	async_mode(info);
4954 	rx_start(info);
4955 	tx_load(info, buf, count);
4956 	spin_unlock_irqrestore(&info->lock, flags);
4957 
4958 	/* wait for receive complete */
4959 	for (timeout = 100; timeout; --timeout) {
4960 		msleep_interruptible(10);
4961 		if (loopback_test_rx(info)) {
4962 			rc = 0;
4963 			break;
4964 		}
4965 	}
4966 
4967 	/* verify received frame length and contents */
4968 	if (!rc && (info->tmp_rbuf_count != count ||
4969 		  memcmp(buf, info->tmp_rbuf, count))) {
4970 		rc = -ENODEV;
4971 	}
4972 
4973 	spin_lock_irqsave(&info->lock,flags);
4974 	reset_adapter(info);
4975 	spin_unlock_irqrestore(&info->lock,flags);
4976 
4977 	memcpy(&info->params, &params, sizeof(info->params));
4978 	info->port.tty = oldtty;
4979 
4980 	info->init_error = rc ? DiagStatus_DmaFailure : 0;
4981 	return rc;
4982 }
4983 
4984 static int adapter_test(struct slgt_info *info)
4985 {
4986 	DBGINFO(("testing %s\n", info->device_name));
4987 	if (register_test(info) < 0) {
4988 		printk("register test failure %s addr=%08X\n",
4989 			info->device_name, info->phys_reg_addr);
4990 	} else if (irq_test(info) < 0) {
4991 		printk("IRQ test failure %s IRQ=%d\n",
4992 			info->device_name, info->irq_level);
4993 	} else if (loopback_test(info) < 0) {
4994 		printk("loopback test failure %s\n", info->device_name);
4995 	}
4996 	return info->init_error;
4997 }
4998 
4999 /*
5000  * transmit timeout handler
5001  */
5002 static void tx_timeout(struct timer_list *t)
5003 {
5004 	struct slgt_info *info = from_timer(info, t, tx_timer);
5005 	unsigned long flags;
5006 
5007 	DBGINFO(("%s tx_timeout\n", info->device_name));
5008 	if(info->tx_active && info->params.mode == MGSL_MODE_HDLC) {
5009 		info->icount.txtimeout++;
5010 	}
5011 	spin_lock_irqsave(&info->lock,flags);
5012 	tx_stop(info);
5013 	spin_unlock_irqrestore(&info->lock,flags);
5014 
5015 #if SYNCLINK_GENERIC_HDLC
5016 	if (info->netcount)
5017 		hdlcdev_tx_done(info);
5018 	else
5019 #endif
5020 		bh_transmit(info);
5021 }
5022 
5023 /*
5024  * receive buffer polling timer
5025  */
5026 static void rx_timeout(struct timer_list *t)
5027 {
5028 	struct slgt_info *info = from_timer(info, t, rx_timer);
5029 	unsigned long flags;
5030 
5031 	DBGINFO(("%s rx_timeout\n", info->device_name));
5032 	spin_lock_irqsave(&info->lock, flags);
5033 	info->pending_bh |= BH_RECEIVE;
5034 	spin_unlock_irqrestore(&info->lock, flags);
5035 	bh_handler(&info->task);
5036 }
5037 
5038