xref: /openbmc/linux/drivers/tty/mxser.c (revision c0c45238)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  *          mxser.c  -- MOXA Smartio/Industio family multiport serial driver.
4  *
5  *      Copyright (C) 1999-2006  Moxa Technologies (support@moxa.com).
6  *	Copyright (C) 2006-2008  Jiri Slaby <jirislaby@gmail.com>
7  *
8  *      This code is loosely based on the 1.8 moxa driver which is based on
9  *	Linux serial driver, written by Linus Torvalds, Theodore T'so and
10  *	others.
11  *
12  *	Fed through a cleanup, indent and remove of non 2.6 code by Alan Cox
13  *	<alan@lxorguk.ukuu.org.uk>. The original 1.8 code is available on
14  *	www.moxa.com.
15  *	- Fixed x86_64 cleanness
16  */
17 
18 #include <linux/module.h>
19 #include <linux/errno.h>
20 #include <linux/signal.h>
21 #include <linux/sched.h>
22 #include <linux/timer.h>
23 #include <linux/interrupt.h>
24 #include <linux/tty.h>
25 #include <linux/tty_flip.h>
26 #include <linux/serial.h>
27 #include <linux/serial_reg.h>
28 #include <linux/major.h>
29 #include <linux/string.h>
30 #include <linux/fcntl.h>
31 #include <linux/ptrace.h>
32 #include <linux/ioport.h>
33 #include <linux/mm.h>
34 #include <linux/delay.h>
35 #include <linux/pci.h>
36 #include <linux/bitops.h>
37 #include <linux/slab.h>
38 #include <linux/ratelimit.h>
39 
40 #include <asm/io.h>
41 #include <asm/irq.h>
42 #include <linux/uaccess.h>
43 
44 /*
45  *	Semi-public control interfaces
46  */
47 
48 /*
49  *	MOXA ioctls
50  */
51 
52 #define MOXA			0x400
53 #define MOXA_SET_OP_MODE	(MOXA + 66)
54 #define MOXA_GET_OP_MODE	(MOXA + 67)
55 
56 #define RS232_MODE		0
57 #define RS485_2WIRE_MODE	1
58 #define RS422_MODE		2
59 #define RS485_4WIRE_MODE	3
60 #define OP_MODE_MASK		3
61 
62 /* --------------------------------------------------- */
63 
64 /*
65  * Follow just what Moxa Must chip defines.
66  *
67  * When LCR register (offset 0x03) is written the following value, the Must chip
68  * will enter enhanced mode. And a write to EFR (offset 0x02) bit 6,7 will
69  * change bank.
70  */
71 #define MOXA_MUST_ENTER_ENHANCED	0xBF
72 
73 /* when enhanced mode is enabled, access to general bank register */
74 #define MOXA_MUST_GDL_REGISTER		0x07
75 #define MOXA_MUST_GDL_MASK		0x7F
76 #define MOXA_MUST_GDL_HAS_BAD_DATA	0x80
77 
78 #define MOXA_MUST_LSR_RERR		0x80	/* error in receive FIFO */
79 /* enhanced register bank select and enhanced mode setting register */
80 /* This works only when LCR register equals to 0xBF */
81 #define MOXA_MUST_EFR_REGISTER		0x02
82 #define MOXA_MUST_EFR_EFRB_ENABLE	0x10 /* enhanced mode enable */
83 /* enhanced register bank set 0, 1, 2 */
84 #define MOXA_MUST_EFR_BANK0		0x00
85 #define MOXA_MUST_EFR_BANK1		0x40
86 #define MOXA_MUST_EFR_BANK2		0x80
87 #define MOXA_MUST_EFR_BANK3		0xC0
88 #define MOXA_MUST_EFR_BANK_MASK		0xC0
89 
90 /* set XON1 value register, when LCR=0xBF and change to bank0 */
91 #define MOXA_MUST_XON1_REGISTER		0x04
92 
93 /* set XON2 value register, when LCR=0xBF and change to bank0 */
94 #define MOXA_MUST_XON2_REGISTER		0x05
95 
96 /* set XOFF1 value register, when LCR=0xBF and change to bank0 */
97 #define MOXA_MUST_XOFF1_REGISTER	0x06
98 
99 /* set XOFF2 value register, when LCR=0xBF and change to bank0 */
100 #define MOXA_MUST_XOFF2_REGISTER	0x07
101 
102 #define MOXA_MUST_RBRTL_REGISTER	0x04
103 #define MOXA_MUST_RBRTH_REGISTER	0x05
104 #define MOXA_MUST_RBRTI_REGISTER	0x06
105 #define MOXA_MUST_THRTL_REGISTER	0x07
106 #define MOXA_MUST_ENUM_REGISTER		0x04
107 #define MOXA_MUST_HWID_REGISTER		0x05
108 #define MOXA_MUST_ECR_REGISTER		0x06
109 #define MOXA_MUST_CSR_REGISTER		0x07
110 
111 #define MOXA_MUST_FCR_GDA_MODE_ENABLE	0x20 /* good data mode enable */
112 #define MOXA_MUST_FCR_GDA_ONLY_ENABLE	0x10 /* only good data put into RxFIFO */
113 
114 #define MOXA_MUST_IER_ECTSI		0x80 /* enable CTS interrupt */
115 #define MOXA_MUST_IER_ERTSI		0x40 /* enable RTS interrupt */
116 #define MOXA_MUST_IER_XINT		0x20 /* enable Xon/Xoff interrupt */
117 #define MOXA_MUST_IER_EGDAI		0x10 /* enable GDA interrupt */
118 
119 #define MOXA_MUST_RECV_ISR		(UART_IER_RDI | MOXA_MUST_IER_EGDAI)
120 
121 /* GDA interrupt pending */
122 #define MOXA_MUST_IIR_GDA		0x1C
123 #define MOXA_MUST_IIR_RDA		0x04
124 #define MOXA_MUST_IIR_RTO		0x0C
125 #define MOXA_MUST_IIR_LSR		0x06
126 
127 /* received Xon/Xoff or specical interrupt pending */
128 #define MOXA_MUST_IIR_XSC		0x10
129 
130 /* RTS/CTS change state interrupt pending */
131 #define MOXA_MUST_IIR_RTSCTS		0x20
132 #define MOXA_MUST_IIR_MASK		0x3E
133 
134 #define MOXA_MUST_MCR_XON_FLAG		0x40
135 #define MOXA_MUST_MCR_XON_ANY		0x80
136 #define MOXA_MUST_MCR_TX_XON		0x08
137 
138 #define MOXA_MUST_EFR_SF_MASK		0x0F /* software flow control on chip mask value */
139 #define MOXA_MUST_EFR_SF_TX1		0x08 /* send Xon1/Xoff1 */
140 #define MOXA_MUST_EFR_SF_TX2		0x04 /* send Xon2/Xoff2 */
141 #define MOXA_MUST_EFR_SF_TX12		0x0C /* send Xon1,Xon2/Xoff1,Xoff2 */
142 #define MOXA_MUST_EFR_SF_TX_NO		0x00 /* don't send Xon/Xoff */
143 #define MOXA_MUST_EFR_SF_TX_MASK	0x0C /* Tx software flow control mask */
144 #define MOXA_MUST_EFR_SF_RX_NO		0x00 /* don't receive Xon/Xoff */
145 #define MOXA_MUST_EFR_SF_RX1		0x02 /* receive Xon1/Xoff1 */
146 #define MOXA_MUST_EFR_SF_RX2		0x01 /* receive Xon2/Xoff2 */
147 #define MOXA_MUST_EFR_SF_RX12		0x03 /* receive Xon1,Xon2/Xoff1,Xoff2 */
148 #define MOXA_MUST_EFR_SF_RX_MASK	0x03 /* Rx software flow control mask */
149 
150 #define	MXSERMAJOR	 174
151 
152 #define MXSER_BOARDS		4	/* Max. boards */
153 #define MXSER_PORTS_PER_BOARD	8	/* Max. ports per board */
154 #define MXSER_PORTS		(MXSER_BOARDS * MXSER_PORTS_PER_BOARD)
155 #define MXSER_ISR_PASS_LIMIT	100
156 
157 #define WAKEUP_CHARS		256
158 
159 #define MXSER_BAUD_BASE		921600
160 #define MXSER_CUSTOM_DIVISOR	(MXSER_BAUD_BASE * 16)
161 
162 #define PCI_DEVICE_ID_MOXA_RC7000	0x0001
163 #define PCI_DEVICE_ID_MOXA_CP102	0x1020
164 #define PCI_DEVICE_ID_MOXA_CP102UL	0x1021
165 #define PCI_DEVICE_ID_MOXA_CP102U	0x1022
166 #define PCI_DEVICE_ID_MOXA_CP102UF	0x1023
167 #define PCI_DEVICE_ID_MOXA_C104		0x1040
168 #define PCI_DEVICE_ID_MOXA_CP104U	0x1041
169 #define PCI_DEVICE_ID_MOXA_CP104JU	0x1042
170 #define PCI_DEVICE_ID_MOXA_CP104EL	0x1043
171 #define PCI_DEVICE_ID_MOXA_POS104UL	0x1044
172 #define PCI_DEVICE_ID_MOXA_CB108	0x1080
173 #define PCI_DEVICE_ID_MOXA_CP112UL	0x1120
174 #define PCI_DEVICE_ID_MOXA_CT114	0x1140
175 #define PCI_DEVICE_ID_MOXA_CP114	0x1141
176 #define PCI_DEVICE_ID_MOXA_CB114	0x1142
177 #define PCI_DEVICE_ID_MOXA_CP114UL	0x1143
178 #define PCI_DEVICE_ID_MOXA_CP118U	0x1180
179 #define PCI_DEVICE_ID_MOXA_CP118EL	0x1181
180 #define PCI_DEVICE_ID_MOXA_CP132	0x1320
181 #define PCI_DEVICE_ID_MOXA_CP132U	0x1321
182 #define PCI_DEVICE_ID_MOXA_CP134U	0x1340
183 #define PCI_DEVICE_ID_MOXA_CB134I	0x1341
184 #define PCI_DEVICE_ID_MOXA_CP138U	0x1380
185 #define PCI_DEVICE_ID_MOXA_C168		0x1680
186 #define PCI_DEVICE_ID_MOXA_CP168U	0x1681
187 #define PCI_DEVICE_ID_MOXA_CP168EL	0x1682
188 
189 #define MXSER_NPORTS(ddata)		((ddata) & 0xffU)
190 #define MXSER_HIGHBAUD			0x0100
191 
192 enum mxser_must_hwid {
193 	MOXA_OTHER_UART		= 0x00,
194 	MOXA_MUST_MU150_HWID	= 0x01,
195 	MOXA_MUST_MU860_HWID	= 0x02,
196 };
197 
198 static const struct {
199 	u8 type;
200 	u8 fifo_size;
201 	u8 rx_high_water;
202 	u8 rx_low_water;
203 	speed_t max_baud;
204 } Gpci_uart_info[] = {
205 	{ MOXA_OTHER_UART,	 16, 14,  1, 921600 },
206 	{ MOXA_MUST_MU150_HWID,	 64, 48, 16, 230400 },
207 	{ MOXA_MUST_MU860_HWID, 128, 96, 32, 921600 }
208 };
209 #define UART_INFO_NUM	ARRAY_SIZE(Gpci_uart_info)
210 
211 
212 /* driver_data correspond to the lines in the structure above
213    see also ISA probe function before you change something */
214 static const struct pci_device_id mxser_pcibrds[] = {
215 	{ PCI_DEVICE_DATA(MOXA, C168,		8) },
216 	{ PCI_DEVICE_DATA(MOXA, C104,		4) },
217 	{ PCI_DEVICE_DATA(MOXA, CP132,		2) },
218 	{ PCI_DEVICE_DATA(MOXA, CP114,		4) },
219 	{ PCI_DEVICE_DATA(MOXA, CT114,		4) },
220 	{ PCI_DEVICE_DATA(MOXA, CP102,		2 | MXSER_HIGHBAUD) },
221 	{ PCI_DEVICE_DATA(MOXA, CP104U,		4) },
222 	{ PCI_DEVICE_DATA(MOXA, CP168U,		8) },
223 	{ PCI_DEVICE_DATA(MOXA, CP132U,		2) },
224 	{ PCI_DEVICE_DATA(MOXA, CP134U,		4) },
225 	{ PCI_DEVICE_DATA(MOXA, CP104JU,	4) },
226 	{ PCI_DEVICE_DATA(MOXA, RC7000,		8) }, /* RC7000 */
227 	{ PCI_DEVICE_DATA(MOXA, CP118U,		8) },
228 	{ PCI_DEVICE_DATA(MOXA, CP102UL,	2) },
229 	{ PCI_DEVICE_DATA(MOXA, CP102U,		2) },
230 	{ PCI_DEVICE_DATA(MOXA, CP118EL,	8) },
231 	{ PCI_DEVICE_DATA(MOXA, CP168EL,	8) },
232 	{ PCI_DEVICE_DATA(MOXA, CP104EL,	4) },
233 	{ PCI_DEVICE_DATA(MOXA, CB108,		8) },
234 	{ PCI_DEVICE_DATA(MOXA, CB114,		4) },
235 	{ PCI_DEVICE_DATA(MOXA, CB134I,		4) },
236 	{ PCI_DEVICE_DATA(MOXA, CP138U,		8) },
237 	{ PCI_DEVICE_DATA(MOXA, POS104UL,	4) },
238 	{ PCI_DEVICE_DATA(MOXA, CP114UL,	4) },
239 	{ PCI_DEVICE_DATA(MOXA, CP102UF,	2) },
240 	{ PCI_DEVICE_DATA(MOXA, CP112UL,	2) },
241 	{ }
242 };
243 MODULE_DEVICE_TABLE(pci, mxser_pcibrds);
244 
245 static int ttymajor = MXSERMAJOR;
246 
247 /* Variables for insmod */
248 
249 MODULE_AUTHOR("Casper Yang");
250 MODULE_DESCRIPTION("MOXA Smartio/Industio Family Multiport Board Device Driver");
251 module_param(ttymajor, int, 0);
252 MODULE_LICENSE("GPL");
253 
254 struct mxser_board;
255 
256 struct mxser_port {
257 	struct tty_port port;
258 	struct mxser_board *board;
259 
260 	unsigned long ioaddr;
261 	unsigned long opmode_ioaddr;
262 
263 	u8 rx_high_water;
264 	u8 rx_low_water;
265 	int type;		/* UART type */
266 
267 	unsigned char x_char;	/* xon/xoff character */
268 	u8 IER;			/* Interrupt Enable Register */
269 	u8 MCR;			/* Modem control register */
270 	u8 FCR;			/* FIFO control register */
271 
272 	struct async_icount icount; /* kernel counters for 4 input interrupts */
273 	unsigned int timeout;
274 
275 	u8 read_status_mask;
276 	u8 ignore_status_mask;
277 	u8 xmit_fifo_size;
278 
279 	spinlock_t slock;
280 };
281 
282 struct mxser_board {
283 	unsigned int idx;
284 	unsigned short nports;
285 	int irq;
286 	unsigned long vector;
287 
288 	enum mxser_must_hwid must_hwid;
289 	speed_t max_baud;
290 
291 	struct mxser_port ports[];
292 };
293 
294 static DECLARE_BITMAP(mxser_boards, MXSER_BOARDS);
295 static struct tty_driver *mxvar_sdriver;
296 
297 static u8 __mxser_must_set_EFR(unsigned long baseio, u8 clear, u8 set,
298 		bool restore_LCR)
299 {
300 	u8 oldlcr, efr;
301 
302 	oldlcr = inb(baseio + UART_LCR);
303 	outb(MOXA_MUST_ENTER_ENHANCED, baseio + UART_LCR);
304 
305 	efr = inb(baseio + MOXA_MUST_EFR_REGISTER);
306 	efr &= ~clear;
307 	efr |= set;
308 
309 	outb(efr, baseio + MOXA_MUST_EFR_REGISTER);
310 
311 	if (restore_LCR)
312 		outb(oldlcr, baseio + UART_LCR);
313 
314 	return oldlcr;
315 }
316 
317 static u8 mxser_must_select_bank(unsigned long baseio, u8 bank)
318 {
319 	return __mxser_must_set_EFR(baseio, MOXA_MUST_EFR_BANK_MASK, bank,
320 			false);
321 }
322 
323 static void mxser_set_must_xon1_value(unsigned long baseio, u8 value)
324 {
325 	u8 oldlcr = mxser_must_select_bank(baseio, MOXA_MUST_EFR_BANK0);
326 	outb(value, baseio + MOXA_MUST_XON1_REGISTER);
327 	outb(oldlcr, baseio + UART_LCR);
328 }
329 
330 static void mxser_set_must_xoff1_value(unsigned long baseio, u8 value)
331 {
332 	u8 oldlcr = mxser_must_select_bank(baseio, MOXA_MUST_EFR_BANK0);
333 	outb(value, baseio + MOXA_MUST_XOFF1_REGISTER);
334 	outb(oldlcr, baseio + UART_LCR);
335 }
336 
337 static void mxser_set_must_fifo_value(struct mxser_port *info)
338 {
339 	u8 oldlcr = mxser_must_select_bank(info->ioaddr, MOXA_MUST_EFR_BANK1);
340 	outb(info->rx_high_water, info->ioaddr + MOXA_MUST_RBRTH_REGISTER);
341 	outb(info->rx_high_water, info->ioaddr + MOXA_MUST_RBRTI_REGISTER);
342 	outb(info->rx_low_water, info->ioaddr + MOXA_MUST_RBRTL_REGISTER);
343 	outb(oldlcr, info->ioaddr + UART_LCR);
344 }
345 
346 static void mxser_set_must_enum_value(unsigned long baseio, u8 value)
347 {
348 	u8 oldlcr = mxser_must_select_bank(baseio, MOXA_MUST_EFR_BANK2);
349 	outb(value, baseio + MOXA_MUST_ENUM_REGISTER);
350 	outb(oldlcr, baseio + UART_LCR);
351 }
352 
353 static u8 mxser_get_must_hardware_id(unsigned long baseio)
354 {
355 	u8 oldlcr = mxser_must_select_bank(baseio, MOXA_MUST_EFR_BANK2);
356 	u8 id = inb(baseio + MOXA_MUST_HWID_REGISTER);
357 	outb(oldlcr, baseio + UART_LCR);
358 
359 	return id;
360 }
361 
362 static void mxser_must_set_EFR(unsigned long baseio, u8 clear, u8 set)
363 {
364 	__mxser_must_set_EFR(baseio, clear, set, true);
365 }
366 
367 static void mxser_must_set_enhance_mode(unsigned long baseio, bool enable)
368 {
369 	mxser_must_set_EFR(baseio,
370 			enable ? 0 : MOXA_MUST_EFR_EFRB_ENABLE,
371 			enable ? MOXA_MUST_EFR_EFRB_ENABLE : 0);
372 }
373 
374 static void mxser_must_no_sw_flow_control(unsigned long baseio)
375 {
376 	mxser_must_set_EFR(baseio, MOXA_MUST_EFR_SF_MASK, 0);
377 }
378 
379 static void mxser_must_set_tx_sw_flow_control(unsigned long baseio, bool enable)
380 {
381 	mxser_must_set_EFR(baseio, MOXA_MUST_EFR_SF_TX_MASK,
382 			enable ? MOXA_MUST_EFR_SF_TX1 : 0);
383 }
384 
385 static void mxser_must_set_rx_sw_flow_control(unsigned long baseio, bool enable)
386 {
387 	mxser_must_set_EFR(baseio, MOXA_MUST_EFR_SF_RX_MASK,
388 			enable ? MOXA_MUST_EFR_SF_RX1 : 0);
389 }
390 
391 static enum mxser_must_hwid mxser_must_get_hwid(unsigned long io)
392 {
393 	u8 oldmcr, hwid;
394 	int i;
395 
396 	outb(0, io + UART_LCR);
397 	mxser_must_set_enhance_mode(io, false);
398 	oldmcr = inb(io + UART_MCR);
399 	outb(0, io + UART_MCR);
400 	mxser_set_must_xon1_value(io, 0x11);
401 	if ((hwid = inb(io + UART_MCR)) != 0) {
402 		outb(oldmcr, io + UART_MCR);
403 		return MOXA_OTHER_UART;
404 	}
405 
406 	hwid = mxser_get_must_hardware_id(io);
407 	for (i = 1; i < UART_INFO_NUM; i++) /* 0 = OTHER_UART */
408 		if (hwid == Gpci_uart_info[i].type)
409 			return hwid;
410 
411 	return MOXA_OTHER_UART;
412 }
413 
414 static bool mxser_16550A_or_MUST(struct mxser_port *info)
415 {
416 	return info->type == PORT_16550A || info->board->must_hwid;
417 }
418 
419 static void mxser_process_txrx_fifo(struct mxser_port *info)
420 {
421 	unsigned int i;
422 
423 	if (info->type == PORT_16450 || info->type == PORT_8250) {
424 		info->rx_high_water = 1;
425 		info->rx_low_water = 1;
426 		info->xmit_fifo_size = 1;
427 		return;
428 	}
429 
430 	for (i = 0; i < UART_INFO_NUM; i++)
431 		if (info->board->must_hwid == Gpci_uart_info[i].type) {
432 			info->rx_low_water = Gpci_uart_info[i].rx_low_water;
433 			info->rx_high_water = Gpci_uart_info[i].rx_high_water;
434 			info->xmit_fifo_size = Gpci_uart_info[i].fifo_size;
435 			break;
436 		}
437 }
438 
439 static void __mxser_start_tx(struct mxser_port *info)
440 {
441 	outb(info->IER & ~UART_IER_THRI, info->ioaddr + UART_IER);
442 	info->IER |= UART_IER_THRI;
443 	outb(info->IER, info->ioaddr + UART_IER);
444 }
445 
446 static void mxser_start_tx(struct mxser_port *info)
447 {
448 	unsigned long flags;
449 
450 	spin_lock_irqsave(&info->slock, flags);
451 	__mxser_start_tx(info);
452 	spin_unlock_irqrestore(&info->slock, flags);
453 }
454 
455 static void __mxser_stop_tx(struct mxser_port *info)
456 {
457 	info->IER &= ~UART_IER_THRI;
458 	outb(info->IER, info->ioaddr + UART_IER);
459 }
460 
461 static int mxser_carrier_raised(struct tty_port *port)
462 {
463 	struct mxser_port *mp = container_of(port, struct mxser_port, port);
464 	return (inb(mp->ioaddr + UART_MSR) & UART_MSR_DCD)?1:0;
465 }
466 
467 static void mxser_dtr_rts(struct tty_port *port, int on)
468 {
469 	struct mxser_port *mp = container_of(port, struct mxser_port, port);
470 	unsigned long flags;
471 	u8 mcr;
472 
473 	spin_lock_irqsave(&mp->slock, flags);
474 	mcr = inb(mp->ioaddr + UART_MCR);
475 	if (on)
476 		mcr |= UART_MCR_DTR | UART_MCR_RTS;
477 	else
478 		mcr &= ~(UART_MCR_DTR | UART_MCR_RTS);
479 	outb(mcr, mp->ioaddr + UART_MCR);
480 	spin_unlock_irqrestore(&mp->slock, flags);
481 }
482 
483 static int mxser_set_baud(struct tty_struct *tty, speed_t newspd)
484 {
485 	struct mxser_port *info = tty->driver_data;
486 	unsigned int quot = 0, baud;
487 	unsigned char cval;
488 	u64 timeout;
489 
490 	if (newspd > info->board->max_baud)
491 		return -1;
492 
493 	if (newspd == 134) {
494 		quot = 2 * MXSER_BAUD_BASE / 269;
495 		tty_encode_baud_rate(tty, 134, 134);
496 	} else if (newspd) {
497 		quot = MXSER_BAUD_BASE / newspd;
498 		if (quot == 0)
499 			quot = 1;
500 		baud = MXSER_BAUD_BASE / quot;
501 		tty_encode_baud_rate(tty, baud, baud);
502 	} else {
503 		quot = 0;
504 	}
505 
506 	/*
507 	 * worst case (128 * 1000 * 10 * 18432) needs 35 bits, so divide in the
508 	 * u64 domain
509 	 */
510 	timeout = (u64)info->xmit_fifo_size * HZ * 10 * quot;
511 	do_div(timeout, MXSER_BAUD_BASE);
512 	info->timeout = timeout + HZ / 50; /* Add .02 seconds of slop */
513 
514 	if (quot) {
515 		info->MCR |= UART_MCR_DTR;
516 		outb(info->MCR, info->ioaddr + UART_MCR);
517 	} else {
518 		info->MCR &= ~UART_MCR_DTR;
519 		outb(info->MCR, info->ioaddr + UART_MCR);
520 		return 0;
521 	}
522 
523 	cval = inb(info->ioaddr + UART_LCR);
524 
525 	outb(cval | UART_LCR_DLAB, info->ioaddr + UART_LCR);	/* set DLAB */
526 
527 	outb(quot & 0xff, info->ioaddr + UART_DLL);	/* LS of divisor */
528 	outb(quot >> 8, info->ioaddr + UART_DLM);	/* MS of divisor */
529 	outb(cval, info->ioaddr + UART_LCR);	/* reset DLAB */
530 
531 #ifdef BOTHER
532 	if (C_BAUD(tty) == BOTHER) {
533 		quot = MXSER_BAUD_BASE % newspd;
534 		quot *= 8;
535 		if (quot % newspd > newspd / 2) {
536 			quot /= newspd;
537 			quot++;
538 		} else
539 			quot /= newspd;
540 
541 		mxser_set_must_enum_value(info->ioaddr, quot);
542 	} else
543 #endif
544 		mxser_set_must_enum_value(info->ioaddr, 0);
545 
546 	return 0;
547 }
548 
549 static void mxser_handle_cts(struct tty_struct *tty, struct mxser_port *info,
550 		u8 msr)
551 {
552 	bool cts = msr & UART_MSR_CTS;
553 
554 	if (tty->hw_stopped) {
555 		if (cts) {
556 			tty->hw_stopped = 0;
557 
558 			if (!mxser_16550A_or_MUST(info))
559 				__mxser_start_tx(info);
560 			tty_wakeup(tty);
561 		}
562 		return;
563 	} else if (cts)
564 		return;
565 
566 	tty->hw_stopped = 1;
567 	if (!mxser_16550A_or_MUST(info))
568 		__mxser_stop_tx(info);
569 }
570 
571 /*
572  * This routine is called to set the UART divisor registers to match
573  * the specified baud rate for a serial port.
574  */
575 static void mxser_change_speed(struct tty_struct *tty, struct ktermios *old_termios)
576 {
577 	struct mxser_port *info = tty->driver_data;
578 	unsigned cflag, cval;
579 
580 	cflag = tty->termios.c_cflag;
581 
582 	if (mxser_set_baud(tty, tty_get_baud_rate(tty))) {
583 		/* Use previous rate on a failure */
584 		if (old_termios) {
585 			speed_t baud = tty_termios_baud_rate(old_termios);
586 			tty_encode_baud_rate(tty, baud, baud);
587 		}
588 	}
589 
590 	/* byte size and parity */
591 	cval = UART_LCR_WLEN(tty_get_char_size(tty->termios.c_cflag));
592 
593 	if (cflag & CSTOPB)
594 		cval |= UART_LCR_STOP;
595 	if (cflag & PARENB)
596 		cval |= UART_LCR_PARITY;
597 	if (!(cflag & PARODD))
598 		cval |= UART_LCR_EPAR;
599 	if (cflag & CMSPAR)
600 		cval |= UART_LCR_SPAR;
601 
602 	info->FCR = 0;
603 	if (info->board->must_hwid) {
604 		info->FCR |= UART_FCR_ENABLE_FIFO |
605 			MOXA_MUST_FCR_GDA_MODE_ENABLE;
606 		mxser_set_must_fifo_value(info);
607 	} else if (info->type != PORT_8250 && info->type != PORT_16450) {
608 		info->FCR |= UART_FCR_ENABLE_FIFO;
609 		switch (info->rx_high_water) {
610 		case 1:
611 			info->FCR |= UART_FCR_TRIGGER_1;
612 			break;
613 		case 4:
614 			info->FCR |= UART_FCR_TRIGGER_4;
615 			break;
616 		case 8:
617 			info->FCR |= UART_FCR_TRIGGER_8;
618 			break;
619 		default:
620 			info->FCR |= UART_FCR_TRIGGER_14;
621 			break;
622 		}
623 	}
624 
625 	/* CTS flow control flag and modem status interrupts */
626 	info->IER &= ~UART_IER_MSI;
627 	info->MCR &= ~UART_MCR_AFE;
628 	tty_port_set_cts_flow(&info->port, cflag & CRTSCTS);
629 	if (cflag & CRTSCTS) {
630 		info->IER |= UART_IER_MSI;
631 		if (mxser_16550A_or_MUST(info)) {
632 			info->MCR |= UART_MCR_AFE;
633 		} else {
634 			mxser_handle_cts(tty, info,
635 					inb(info->ioaddr + UART_MSR));
636 		}
637 	}
638 	outb(info->MCR, info->ioaddr + UART_MCR);
639 	tty_port_set_check_carrier(&info->port, ~cflag & CLOCAL);
640 	if (~cflag & CLOCAL)
641 		info->IER |= UART_IER_MSI;
642 	outb(info->IER, info->ioaddr + UART_IER);
643 
644 	/*
645 	 * Set up parity check flag
646 	 */
647 	info->read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
648 	if (I_INPCK(tty))
649 		info->read_status_mask |= UART_LSR_FE | UART_LSR_PE;
650 	if (I_BRKINT(tty) || I_PARMRK(tty))
651 		info->read_status_mask |= UART_LSR_BI;
652 
653 	info->ignore_status_mask = 0;
654 
655 	if (I_IGNBRK(tty)) {
656 		info->ignore_status_mask |= UART_LSR_BI;
657 		info->read_status_mask |= UART_LSR_BI;
658 		/*
659 		 * If we're ignore parity and break indicators, ignore
660 		 * overruns too.  (For real raw support).
661 		 */
662 		if (I_IGNPAR(tty)) {
663 			info->ignore_status_mask |=
664 						UART_LSR_OE |
665 						UART_LSR_PE |
666 						UART_LSR_FE;
667 			info->read_status_mask |=
668 						UART_LSR_OE |
669 						UART_LSR_PE |
670 						UART_LSR_FE;
671 		}
672 	}
673 	if (info->board->must_hwid) {
674 		mxser_set_must_xon1_value(info->ioaddr, START_CHAR(tty));
675 		mxser_set_must_xoff1_value(info->ioaddr, STOP_CHAR(tty));
676 		mxser_must_set_rx_sw_flow_control(info->ioaddr, I_IXON(tty));
677 		mxser_must_set_tx_sw_flow_control(info->ioaddr, I_IXOFF(tty));
678 	}
679 
680 
681 	outb(info->FCR, info->ioaddr + UART_FCR);
682 	outb(cval, info->ioaddr + UART_LCR);
683 }
684 
685 static u8 mxser_check_modem_status(struct tty_struct *tty,
686 				struct mxser_port *port)
687 {
688 	u8 msr = inb(port->ioaddr + UART_MSR);
689 
690 	if (!(msr & UART_MSR_ANY_DELTA))
691 		return msr;
692 
693 	/* update input line counters */
694 	if (msr & UART_MSR_TERI)
695 		port->icount.rng++;
696 	if (msr & UART_MSR_DDSR)
697 		port->icount.dsr++;
698 	if (msr & UART_MSR_DDCD)
699 		port->icount.dcd++;
700 	if (msr & UART_MSR_DCTS)
701 		port->icount.cts++;
702 	wake_up_interruptible(&port->port.delta_msr_wait);
703 
704 	if (tty_port_check_carrier(&port->port) && (msr & UART_MSR_DDCD)) {
705 		if (msr & UART_MSR_DCD)
706 			wake_up_interruptible(&port->port.open_wait);
707 	}
708 
709 	if (tty_port_cts_enabled(&port->port))
710 		mxser_handle_cts(tty, port, msr);
711 
712 	return msr;
713 }
714 
715 static void mxser_disable_and_clear_FIFO(struct mxser_port *info)
716 {
717 	u8 fcr = UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT;
718 
719 	if (info->board->must_hwid)
720 		fcr |= MOXA_MUST_FCR_GDA_MODE_ENABLE;
721 
722 	outb(fcr, info->ioaddr + UART_FCR);
723 }
724 
725 static int mxser_activate(struct tty_port *port, struct tty_struct *tty)
726 {
727 	struct mxser_port *info = container_of(port, struct mxser_port, port);
728 	unsigned long flags;
729 	int ret;
730 
731 	ret = tty_port_alloc_xmit_buf(port);
732 	if (ret < 0)
733 		return ret;
734 
735 	spin_lock_irqsave(&info->slock, flags);
736 
737 	if (!info->type) {
738 		set_bit(TTY_IO_ERROR, &tty->flags);
739 		spin_unlock_irqrestore(&info->slock, flags);
740 		ret = 0;
741 		goto err_free_xmit;
742 	}
743 
744 	/*
745 	 * Clear the FIFO buffers and disable them
746 	 * (they will be reenabled in mxser_change_speed())
747 	 */
748 	mxser_disable_and_clear_FIFO(info);
749 
750 	/*
751 	 * At this point there's no way the LSR could still be 0xFF;
752 	 * if it is, then bail out, because there's likely no UART
753 	 * here.
754 	 */
755 	if (inb(info->ioaddr + UART_LSR) == 0xff) {
756 		spin_unlock_irqrestore(&info->slock, flags);
757 		if (capable(CAP_SYS_ADMIN)) {
758 			set_bit(TTY_IO_ERROR, &tty->flags);
759 			return 0;
760 		}
761 
762 		ret = -ENODEV;
763 		goto err_free_xmit;
764 	}
765 
766 	/*
767 	 * Clear the interrupt registers.
768 	 */
769 	(void) inb(info->ioaddr + UART_LSR);
770 	(void) inb(info->ioaddr + UART_RX);
771 	(void) inb(info->ioaddr + UART_IIR);
772 	(void) inb(info->ioaddr + UART_MSR);
773 
774 	/*
775 	 * Now, initialize the UART
776 	 */
777 	outb(UART_LCR_WLEN8, info->ioaddr + UART_LCR);	/* reset DLAB */
778 	info->MCR = UART_MCR_DTR | UART_MCR_RTS;
779 	outb(info->MCR, info->ioaddr + UART_MCR);
780 
781 	/*
782 	 * Finally, enable interrupts
783 	 */
784 	info->IER = UART_IER_MSI | UART_IER_RLSI | UART_IER_RDI;
785 
786 	if (info->board->must_hwid)
787 		info->IER |= MOXA_MUST_IER_EGDAI;
788 	outb(info->IER, info->ioaddr + UART_IER);	/* enable interrupts */
789 
790 	/*
791 	 * And clear the interrupt registers again for luck.
792 	 */
793 	(void) inb(info->ioaddr + UART_LSR);
794 	(void) inb(info->ioaddr + UART_RX);
795 	(void) inb(info->ioaddr + UART_IIR);
796 	(void) inb(info->ioaddr + UART_MSR);
797 
798 	clear_bit(TTY_IO_ERROR, &tty->flags);
799 	kfifo_reset(&port->xmit_fifo);
800 
801 	/*
802 	 * and set the speed of the serial port
803 	 */
804 	mxser_change_speed(tty, NULL);
805 	spin_unlock_irqrestore(&info->slock, flags);
806 
807 	return 0;
808 err_free_xmit:
809 	tty_port_free_xmit_buf(port);
810 	return ret;
811 }
812 
813 /*
814  * To stop accepting input, we disable the receive line status interrupts, and
815  * tell the interrupt driver to stop checking the data ready bit in the line
816  * status register.
817  */
818 static void mxser_stop_rx(struct mxser_port *info)
819 {
820 	info->IER &= ~UART_IER_RLSI;
821 	if (info->board->must_hwid)
822 		info->IER &= ~MOXA_MUST_RECV_ISR;
823 
824 	outb(info->IER, info->ioaddr + UART_IER);
825 }
826 
827 /*
828  * This routine will shutdown a serial port
829  */
830 static void mxser_shutdown_port(struct tty_port *port)
831 {
832 	struct mxser_port *info = container_of(port, struct mxser_port, port);
833 	unsigned long flags;
834 
835 	spin_lock_irqsave(&info->slock, flags);
836 
837 	mxser_stop_rx(info);
838 
839 	/*
840 	 * clear delta_msr_wait queue to avoid mem leaks: we may free the irq
841 	 * here so the queue might never be waken up
842 	 */
843 	wake_up_interruptible(&info->port.delta_msr_wait);
844 
845 	info->IER = 0;
846 	outb(0x00, info->ioaddr + UART_IER);
847 
848 	/* clear Rx/Tx FIFO's */
849 	mxser_disable_and_clear_FIFO(info);
850 
851 	/* read data port to reset things */
852 	(void) inb(info->ioaddr + UART_RX);
853 
854 
855 	if (info->board->must_hwid)
856 		mxser_must_no_sw_flow_control(info->ioaddr);
857 
858 	spin_unlock_irqrestore(&info->slock, flags);
859 
860 	/* make sure ISR is not running while we free the buffer */
861 	synchronize_irq(info->board->irq);
862 
863 	tty_port_free_xmit_buf(port);
864 }
865 
866 /*
867  * This routine is called whenever a serial port is opened.  It
868  * enables interrupts for a serial port, linking in its async structure into
869  * the IRQ chain.   It also performs the serial-specific
870  * initialization for the tty structure.
871  */
872 static int mxser_open(struct tty_struct *tty, struct file *filp)
873 {
874 	struct tty_port *tport = tty->port;
875 	struct mxser_port *port = container_of(tport, struct mxser_port, port);
876 
877 	tty->driver_data = port;
878 
879 	return tty_port_open(tport, tty, filp);
880 }
881 
882 static void mxser_flush_buffer(struct tty_struct *tty)
883 {
884 	struct mxser_port *info = tty->driver_data;
885 	unsigned long flags;
886 
887 	spin_lock_irqsave(&info->slock, flags);
888 	kfifo_reset(&info->port.xmit_fifo);
889 
890 	outb(info->FCR | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT,
891 		info->ioaddr + UART_FCR);
892 
893 	spin_unlock_irqrestore(&info->slock, flags);
894 
895 	tty_wakeup(tty);
896 }
897 
898 static void mxser_close(struct tty_struct *tty, struct file *filp)
899 {
900 	tty_port_close(tty->port, tty, filp);
901 }
902 
903 static int mxser_write(struct tty_struct *tty, const unsigned char *buf, int count)
904 {
905 	struct mxser_port *info = tty->driver_data;
906 	unsigned long flags;
907 	int written;
908 	bool is_empty;
909 
910 	spin_lock_irqsave(&info->slock, flags);
911 	written = kfifo_in(&info->port.xmit_fifo, buf, count);
912 	is_empty = kfifo_is_empty(&info->port.xmit_fifo);
913 	spin_unlock_irqrestore(&info->slock, flags);
914 
915 	if (!is_empty && !tty->flow.stopped)
916 		if (!tty->hw_stopped || mxser_16550A_or_MUST(info))
917 			mxser_start_tx(info);
918 
919 	return written;
920 }
921 
922 static int mxser_put_char(struct tty_struct *tty, unsigned char ch)
923 {
924 	struct mxser_port *info = tty->driver_data;
925 	unsigned long flags;
926 	int ret;
927 
928 	spin_lock_irqsave(&info->slock, flags);
929 	ret = kfifo_put(&info->port.xmit_fifo, ch);
930 	spin_unlock_irqrestore(&info->slock, flags);
931 
932 	return ret;
933 }
934 
935 
936 static void mxser_flush_chars(struct tty_struct *tty)
937 {
938 	struct mxser_port *info = tty->driver_data;
939 
940 	if (kfifo_is_empty(&info->port.xmit_fifo) || tty->flow.stopped ||
941 			(tty->hw_stopped && !mxser_16550A_or_MUST(info)))
942 		return;
943 
944 	mxser_start_tx(info);
945 }
946 
947 static unsigned int mxser_write_room(struct tty_struct *tty)
948 {
949 	struct mxser_port *info = tty->driver_data;
950 
951 	return kfifo_avail(&info->port.xmit_fifo);
952 }
953 
954 static unsigned int mxser_chars_in_buffer(struct tty_struct *tty)
955 {
956 	struct mxser_port *info = tty->driver_data;
957 
958 	return kfifo_len(&info->port.xmit_fifo);
959 }
960 
961 /*
962  * ------------------------------------------------------------
963  * friends of mxser_ioctl()
964  * ------------------------------------------------------------
965  */
966 static int mxser_get_serial_info(struct tty_struct *tty,
967 		struct serial_struct *ss)
968 {
969 	struct mxser_port *info = tty->driver_data;
970 	struct tty_port *port = &info->port;
971 	unsigned int closing_wait, close_delay;
972 
973 	mutex_lock(&port->mutex);
974 
975 	close_delay = jiffies_to_msecs(info->port.close_delay) / 10;
976 	closing_wait = info->port.closing_wait;
977 	if (closing_wait != ASYNC_CLOSING_WAIT_NONE)
978 		closing_wait = jiffies_to_msecs(closing_wait) / 10;
979 
980 	ss->type = info->type;
981 	ss->line = tty->index;
982 	ss->port = info->ioaddr;
983 	ss->irq = info->board->irq;
984 	ss->flags = info->port.flags;
985 	ss->baud_base = MXSER_BAUD_BASE;
986 	ss->close_delay = close_delay;
987 	ss->closing_wait = closing_wait;
988 	ss->custom_divisor = MXSER_CUSTOM_DIVISOR,
989 	mutex_unlock(&port->mutex);
990 	return 0;
991 }
992 
993 static int mxser_set_serial_info(struct tty_struct *tty,
994 		struct serial_struct *ss)
995 {
996 	struct mxser_port *info = tty->driver_data;
997 	struct tty_port *port = &info->port;
998 	speed_t baud;
999 	unsigned long sl_flags;
1000 	unsigned int old_speed, close_delay, closing_wait;
1001 	int retval = 0;
1002 
1003 	if (tty_io_error(tty))
1004 		return -EIO;
1005 
1006 	mutex_lock(&port->mutex);
1007 
1008 	if (ss->irq != info->board->irq ||
1009 			ss->port != info->ioaddr) {
1010 		mutex_unlock(&port->mutex);
1011 		return -EINVAL;
1012 	}
1013 
1014 	old_speed = port->flags & ASYNC_SPD_MASK;
1015 
1016 	close_delay = msecs_to_jiffies(ss->close_delay * 10);
1017 	closing_wait = ss->closing_wait;
1018 	if (closing_wait != ASYNC_CLOSING_WAIT_NONE)
1019 		closing_wait = msecs_to_jiffies(closing_wait * 10);
1020 
1021 	if (!capable(CAP_SYS_ADMIN)) {
1022 		if ((ss->baud_base != MXSER_BAUD_BASE) ||
1023 				(close_delay != port->close_delay) ||
1024 				(closing_wait != port->closing_wait) ||
1025 				((ss->flags & ~ASYNC_USR_MASK) != (port->flags & ~ASYNC_USR_MASK))) {
1026 			mutex_unlock(&port->mutex);
1027 			return -EPERM;
1028 		}
1029 		port->flags = (port->flags & ~ASYNC_USR_MASK) |
1030 				(ss->flags & ASYNC_USR_MASK);
1031 	} else {
1032 		/*
1033 		 * OK, past this point, all the error checking has been done.
1034 		 * At this point, we start making changes.....
1035 		 */
1036 		port->flags = ((port->flags & ~ASYNC_FLAGS) |
1037 				(ss->flags & ASYNC_FLAGS));
1038 		port->close_delay = close_delay;
1039 		port->closing_wait = closing_wait;
1040 		if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST &&
1041 				(ss->baud_base != MXSER_BAUD_BASE ||
1042 				ss->custom_divisor !=
1043 				MXSER_CUSTOM_DIVISOR)) {
1044 			if (ss->custom_divisor == 0) {
1045 				mutex_unlock(&port->mutex);
1046 				return -EINVAL;
1047 			}
1048 			baud = ss->baud_base / ss->custom_divisor;
1049 			tty_encode_baud_rate(tty, baud, baud);
1050 		}
1051 
1052 		info->type = ss->type;
1053 
1054 		mxser_process_txrx_fifo(info);
1055 	}
1056 
1057 	if (tty_port_initialized(port)) {
1058 		if (old_speed != (port->flags & ASYNC_SPD_MASK)) {
1059 			spin_lock_irqsave(&info->slock, sl_flags);
1060 			mxser_change_speed(tty, NULL);
1061 			spin_unlock_irqrestore(&info->slock, sl_flags);
1062 		}
1063 	} else {
1064 		retval = mxser_activate(port, tty);
1065 		if (retval == 0)
1066 			tty_port_set_initialized(port, 1);
1067 	}
1068 	mutex_unlock(&port->mutex);
1069 	return retval;
1070 }
1071 
1072 /*
1073  * mxser_get_lsr_info - get line status register info
1074  *
1075  * Purpose: Let user call ioctl() to get info when the UART physically
1076  *	    is emptied.  On bus types like RS485, the transmitter must
1077  *	    release the bus after transmitting. This must be done when
1078  *	    the transmit shift register is empty, not be done when the
1079  *	    transmit holding register is empty.  This functionality
1080  *	    allows an RS485 driver to be written in user space.
1081  */
1082 static int mxser_get_lsr_info(struct mxser_port *info,
1083 		unsigned int __user *value)
1084 {
1085 	unsigned char status;
1086 	unsigned int result;
1087 	unsigned long flags;
1088 
1089 	spin_lock_irqsave(&info->slock, flags);
1090 	status = inb(info->ioaddr + UART_LSR);
1091 	spin_unlock_irqrestore(&info->slock, flags);
1092 	result = ((status & UART_LSR_TEMT) ? TIOCSER_TEMT : 0);
1093 	return put_user(result, value);
1094 }
1095 
1096 static int mxser_tiocmget(struct tty_struct *tty)
1097 {
1098 	struct mxser_port *info = tty->driver_data;
1099 	unsigned char control;
1100 	unsigned long flags;
1101 	u8 msr;
1102 
1103 	if (tty_io_error(tty))
1104 		return -EIO;
1105 
1106 	spin_lock_irqsave(&info->slock, flags);
1107 	control = info->MCR;
1108 	msr = mxser_check_modem_status(tty, info);
1109 	spin_unlock_irqrestore(&info->slock, flags);
1110 
1111 	return ((control & UART_MCR_RTS) ? TIOCM_RTS : 0) |
1112 		    ((control & UART_MCR_DTR) ? TIOCM_DTR : 0) |
1113 		    ((msr & UART_MSR_DCD) ? TIOCM_CAR : 0) |
1114 		    ((msr & UART_MSR_RI) ? TIOCM_RNG : 0) |
1115 		    ((msr & UART_MSR_DSR) ? TIOCM_DSR : 0) |
1116 		    ((msr & UART_MSR_CTS) ? TIOCM_CTS : 0);
1117 }
1118 
1119 static int mxser_tiocmset(struct tty_struct *tty,
1120 		unsigned int set, unsigned int clear)
1121 {
1122 	struct mxser_port *info = tty->driver_data;
1123 	unsigned long flags;
1124 
1125 	if (tty_io_error(tty))
1126 		return -EIO;
1127 
1128 	spin_lock_irqsave(&info->slock, flags);
1129 
1130 	if (set & TIOCM_RTS)
1131 		info->MCR |= UART_MCR_RTS;
1132 	if (set & TIOCM_DTR)
1133 		info->MCR |= UART_MCR_DTR;
1134 
1135 	if (clear & TIOCM_RTS)
1136 		info->MCR &= ~UART_MCR_RTS;
1137 	if (clear & TIOCM_DTR)
1138 		info->MCR &= ~UART_MCR_DTR;
1139 
1140 	outb(info->MCR, info->ioaddr + UART_MCR);
1141 	spin_unlock_irqrestore(&info->slock, flags);
1142 	return 0;
1143 }
1144 
1145 static int mxser_cflags_changed(struct mxser_port *info, unsigned long arg,
1146 		struct async_icount *cprev)
1147 {
1148 	struct async_icount cnow;
1149 	unsigned long flags;
1150 	int ret;
1151 
1152 	spin_lock_irqsave(&info->slock, flags);
1153 	cnow = info->icount;	/* atomic copy */
1154 	spin_unlock_irqrestore(&info->slock, flags);
1155 
1156 	ret =	((arg & TIOCM_RNG) && (cnow.rng != cprev->rng)) ||
1157 		((arg & TIOCM_DSR) && (cnow.dsr != cprev->dsr)) ||
1158 		((arg & TIOCM_CD)  && (cnow.dcd != cprev->dcd)) ||
1159 		((arg & TIOCM_CTS) && (cnow.cts != cprev->cts));
1160 
1161 	*cprev = cnow;
1162 
1163 	return ret;
1164 }
1165 
1166 /* We should likely switch to TIOCGRS485/TIOCSRS485. */
1167 static int mxser_ioctl_op_mode(struct mxser_port *port, int index, bool set,
1168 		int __user *u_opmode)
1169 {
1170 	int opmode, p = index % 4;
1171 	int shiftbit = p * 2;
1172 	u8 val;
1173 
1174 	if (port->board->must_hwid != MOXA_MUST_MU860_HWID)
1175 		return -EFAULT;
1176 
1177 	if (set) {
1178 		if (get_user(opmode, u_opmode))
1179 			return -EFAULT;
1180 
1181 		if (opmode & ~OP_MODE_MASK)
1182 			return -EINVAL;
1183 
1184 		spin_lock_irq(&port->slock);
1185 		val = inb(port->opmode_ioaddr);
1186 		val &= ~(OP_MODE_MASK << shiftbit);
1187 		val |= (opmode << shiftbit);
1188 		outb(val, port->opmode_ioaddr);
1189 		spin_unlock_irq(&port->slock);
1190 
1191 		return 0;
1192 	}
1193 
1194 	spin_lock_irq(&port->slock);
1195 	opmode = inb(port->opmode_ioaddr) >> shiftbit;
1196 	spin_unlock_irq(&port->slock);
1197 
1198 	return put_user(opmode & OP_MODE_MASK, u_opmode);
1199 }
1200 
1201 static int mxser_ioctl(struct tty_struct *tty,
1202 		unsigned int cmd, unsigned long arg)
1203 {
1204 	struct mxser_port *info = tty->driver_data;
1205 	struct async_icount cnow;
1206 	unsigned long flags;
1207 	void __user *argp = (void __user *)arg;
1208 
1209 	if (cmd == MOXA_SET_OP_MODE || cmd == MOXA_GET_OP_MODE)
1210 		return mxser_ioctl_op_mode(info, tty->index,
1211 				cmd == MOXA_SET_OP_MODE, argp);
1212 
1213 	if (cmd != TIOCMIWAIT && tty_io_error(tty))
1214 		return -EIO;
1215 
1216 	switch (cmd) {
1217 	case TIOCSERGETLSR:	/* Get line status register */
1218 		return  mxser_get_lsr_info(info, argp);
1219 		/*
1220 		 * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change
1221 		 * - mask passed in arg for lines of interest
1222 		 *   (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
1223 		 * Caller should use TIOCGICOUNT to see which one it was
1224 		 */
1225 	case TIOCMIWAIT:
1226 		spin_lock_irqsave(&info->slock, flags);
1227 		cnow = info->icount;	/* note the counters on entry */
1228 		spin_unlock_irqrestore(&info->slock, flags);
1229 
1230 		return wait_event_interruptible(info->port.delta_msr_wait,
1231 				mxser_cflags_changed(info, arg, &cnow));
1232 	default:
1233 		return -ENOIOCTLCMD;
1234 	}
1235 	return 0;
1236 }
1237 
1238 	/*
1239 	 * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
1240 	 * Return: write counters to the user passed counter struct
1241 	 * NB: both 1->0 and 0->1 transitions are counted except for
1242 	 *     RI where only 0->1 is counted.
1243 	 */
1244 
1245 static int mxser_get_icount(struct tty_struct *tty,
1246 		struct serial_icounter_struct *icount)
1247 
1248 {
1249 	struct mxser_port *info = tty->driver_data;
1250 	struct async_icount cnow;
1251 	unsigned long flags;
1252 
1253 	spin_lock_irqsave(&info->slock, flags);
1254 	cnow = info->icount;
1255 	spin_unlock_irqrestore(&info->slock, flags);
1256 
1257 	icount->frame = cnow.frame;
1258 	icount->brk = cnow.brk;
1259 	icount->overrun = cnow.overrun;
1260 	icount->buf_overrun = cnow.buf_overrun;
1261 	icount->parity = cnow.parity;
1262 	icount->rx = cnow.rx;
1263 	icount->tx = cnow.tx;
1264 	icount->cts = cnow.cts;
1265 	icount->dsr = cnow.dsr;
1266 	icount->rng = cnow.rng;
1267 	icount->dcd = cnow.dcd;
1268 	return 0;
1269 }
1270 
1271 /*
1272  * This routine is called by the upper-layer tty layer to signal that
1273  * incoming characters should be throttled.
1274  */
1275 static void mxser_throttle(struct tty_struct *tty)
1276 {
1277 	struct mxser_port *info = tty->driver_data;
1278 
1279 	if (I_IXOFF(tty)) {
1280 		if (info->board->must_hwid) {
1281 			info->IER &= ~MOXA_MUST_RECV_ISR;
1282 			outb(info->IER, info->ioaddr + UART_IER);
1283 		} else {
1284 			info->x_char = STOP_CHAR(tty);
1285 			outb(0, info->ioaddr + UART_IER);
1286 			info->IER |= UART_IER_THRI;
1287 			outb(info->IER, info->ioaddr + UART_IER);
1288 		}
1289 	}
1290 
1291 	if (C_CRTSCTS(tty)) {
1292 		info->MCR &= ~UART_MCR_RTS;
1293 		outb(info->MCR, info->ioaddr + UART_MCR);
1294 	}
1295 }
1296 
1297 static void mxser_unthrottle(struct tty_struct *tty)
1298 {
1299 	struct mxser_port *info = tty->driver_data;
1300 
1301 	/* startrx */
1302 	if (I_IXOFF(tty)) {
1303 		if (info->x_char)
1304 			info->x_char = 0;
1305 		else {
1306 			if (info->board->must_hwid) {
1307 				info->IER |= MOXA_MUST_RECV_ISR;
1308 				outb(info->IER, info->ioaddr + UART_IER);
1309 			} else {
1310 				info->x_char = START_CHAR(tty);
1311 				outb(0, info->ioaddr + UART_IER);
1312 				info->IER |= UART_IER_THRI;
1313 				outb(info->IER, info->ioaddr + UART_IER);
1314 			}
1315 		}
1316 	}
1317 
1318 	if (C_CRTSCTS(tty)) {
1319 		info->MCR |= UART_MCR_RTS;
1320 		outb(info->MCR, info->ioaddr + UART_MCR);
1321 	}
1322 }
1323 
1324 /*
1325  * mxser_stop() and mxser_start()
1326  *
1327  * This routines are called before setting or resetting tty->flow.stopped.
1328  * They enable or disable transmitter interrupts, as necessary.
1329  */
1330 static void mxser_stop(struct tty_struct *tty)
1331 {
1332 	struct mxser_port *info = tty->driver_data;
1333 	unsigned long flags;
1334 
1335 	spin_lock_irqsave(&info->slock, flags);
1336 	if (info->IER & UART_IER_THRI)
1337 		__mxser_stop_tx(info);
1338 	spin_unlock_irqrestore(&info->slock, flags);
1339 }
1340 
1341 static void mxser_start(struct tty_struct *tty)
1342 {
1343 	struct mxser_port *info = tty->driver_data;
1344 	unsigned long flags;
1345 
1346 	spin_lock_irqsave(&info->slock, flags);
1347 	if (!kfifo_is_empty(&info->port.xmit_fifo))
1348 		__mxser_start_tx(info);
1349 	spin_unlock_irqrestore(&info->slock, flags);
1350 }
1351 
1352 static void mxser_set_termios(struct tty_struct *tty, struct ktermios *old_termios)
1353 {
1354 	struct mxser_port *info = tty->driver_data;
1355 	unsigned long flags;
1356 
1357 	spin_lock_irqsave(&info->slock, flags);
1358 	mxser_change_speed(tty, old_termios);
1359 	spin_unlock_irqrestore(&info->slock, flags);
1360 
1361 	if ((old_termios->c_cflag & CRTSCTS) && !C_CRTSCTS(tty)) {
1362 		tty->hw_stopped = 0;
1363 		mxser_start(tty);
1364 	}
1365 
1366 	/* Handle sw stopped */
1367 	if ((old_termios->c_iflag & IXON) && !I_IXON(tty)) {
1368 		tty->flow.stopped = 0;
1369 
1370 		if (info->board->must_hwid) {
1371 			spin_lock_irqsave(&info->slock, flags);
1372 			mxser_must_set_rx_sw_flow_control(info->ioaddr, false);
1373 			spin_unlock_irqrestore(&info->slock, flags);
1374 		}
1375 
1376 		mxser_start(tty);
1377 	}
1378 }
1379 
1380 static bool mxser_tx_empty(struct mxser_port *info)
1381 {
1382 	unsigned long flags;
1383 	u8 lsr;
1384 
1385 	spin_lock_irqsave(&info->slock, flags);
1386 	lsr = inb(info->ioaddr + UART_LSR);
1387 	spin_unlock_irqrestore(&info->slock, flags);
1388 
1389 	return !(lsr & UART_LSR_TEMT);
1390 }
1391 
1392 /*
1393  * mxser_wait_until_sent() --- wait until the transmitter is empty
1394  */
1395 static void mxser_wait_until_sent(struct tty_struct *tty, int timeout)
1396 {
1397 	struct mxser_port *info = tty->driver_data;
1398 	unsigned long expire, char_time;
1399 
1400 	if (info->type == PORT_UNKNOWN)
1401 		return;
1402 
1403 	if (info->xmit_fifo_size == 0)
1404 		return;		/* Just in case.... */
1405 
1406 	/*
1407 	 * Set the check interval to be 1/5 of the estimated time to
1408 	 * send a single character, and make it at least 1.  The check
1409 	 * interval should also be less than the timeout.
1410 	 *
1411 	 * Note: we have to use pretty tight timings here to satisfy
1412 	 * the NIST-PCTS.
1413 	 */
1414 	char_time = (info->timeout - HZ / 50) / info->xmit_fifo_size;
1415 	char_time = char_time / 5;
1416 	if (char_time == 0)
1417 		char_time = 1;
1418 	if (timeout && timeout < char_time)
1419 		char_time = timeout;
1420 
1421 	char_time = jiffies_to_msecs(char_time);
1422 
1423 	/*
1424 	 * If the transmitter hasn't cleared in twice the approximate
1425 	 * amount of time to send the entire FIFO, it probably won't
1426 	 * ever clear.  This assumes the UART isn't doing flow
1427 	 * control, which is currently the case.  Hence, if it ever
1428 	 * takes longer than info->timeout, this is probably due to a
1429 	 * UART bug of some kind.  So, we clamp the timeout parameter at
1430 	 * 2*info->timeout.
1431 	 */
1432 	if (!timeout || timeout > 2 * info->timeout)
1433 		timeout = 2 * info->timeout;
1434 
1435 	expire = jiffies + timeout;
1436 
1437 	while (mxser_tx_empty(info)) {
1438 		msleep_interruptible(char_time);
1439 		if (signal_pending(current))
1440 			break;
1441 		if (time_after(jiffies, expire))
1442 			break;
1443 	}
1444 }
1445 
1446 /*
1447  * This routine is called by tty_hangup() when a hangup is signaled.
1448  */
1449 static void mxser_hangup(struct tty_struct *tty)
1450 {
1451 	struct mxser_port *info = tty->driver_data;
1452 
1453 	mxser_flush_buffer(tty);
1454 	tty_port_hangup(&info->port);
1455 }
1456 
1457 /*
1458  * mxser_rs_break() --- routine which turns the break handling on or off
1459  */
1460 static int mxser_rs_break(struct tty_struct *tty, int break_state)
1461 {
1462 	struct mxser_port *info = tty->driver_data;
1463 	unsigned long flags;
1464 	u8 lcr;
1465 
1466 	spin_lock_irqsave(&info->slock, flags);
1467 	lcr = inb(info->ioaddr + UART_LCR);
1468 	if (break_state == -1)
1469 		lcr |= UART_LCR_SBC;
1470 	else
1471 		lcr &= ~UART_LCR_SBC;
1472 	outb(lcr, info->ioaddr + UART_LCR);
1473 	spin_unlock_irqrestore(&info->slock, flags);
1474 
1475 	return 0;
1476 }
1477 
1478 static bool mxser_receive_chars_new(struct mxser_port *port, u8 status)
1479 {
1480 	enum mxser_must_hwid hwid = port->board->must_hwid;
1481 	u8 gdl;
1482 
1483 	if (hwid == MOXA_OTHER_UART)
1484 		return false;
1485 	if (status & (UART_LSR_BRK_ERROR_BITS | MOXA_MUST_LSR_RERR))
1486 		return false;
1487 
1488 	gdl = inb(port->ioaddr + MOXA_MUST_GDL_REGISTER);
1489 	if (hwid == MOXA_MUST_MU150_HWID)
1490 		gdl &= MOXA_MUST_GDL_MASK;
1491 
1492 	while (gdl--) {
1493 		u8 ch = inb(port->ioaddr + UART_RX);
1494 		if (!tty_insert_flip_char(&port->port, ch, 0))
1495 			port->icount.buf_overrun++;
1496 	}
1497 
1498 	return true;
1499 }
1500 
1501 static u8 mxser_receive_chars_old(struct tty_struct *tty,
1502 		                struct mxser_port *port, u8 status)
1503 {
1504 	enum mxser_must_hwid hwid = port->board->must_hwid;
1505 	int ignored = 0;
1506 	int max = 256;
1507 	u8 ch;
1508 
1509 	do {
1510 		if (max-- < 0)
1511 			break;
1512 
1513 		ch = inb(port->ioaddr + UART_RX);
1514 		if (hwid && (status & UART_LSR_OE))
1515 			outb(port->FCR | UART_FCR_CLEAR_RCVR,
1516 					port->ioaddr + UART_FCR);
1517 		status &= port->read_status_mask;
1518 		if (status & port->ignore_status_mask) {
1519 			if (++ignored > 100)
1520 				break;
1521 		} else {
1522 			char flag = 0;
1523 			if (status & UART_LSR_BRK_ERROR_BITS) {
1524 				if (status & UART_LSR_BI) {
1525 					flag = TTY_BREAK;
1526 					port->icount.brk++;
1527 
1528 					if (port->port.flags & ASYNC_SAK)
1529 						do_SAK(tty);
1530 				} else if (status & UART_LSR_PE) {
1531 					flag = TTY_PARITY;
1532 					port->icount.parity++;
1533 				} else if (status & UART_LSR_FE) {
1534 					flag = TTY_FRAME;
1535 					port->icount.frame++;
1536 				} else if (status & UART_LSR_OE) {
1537 					flag = TTY_OVERRUN;
1538 					port->icount.overrun++;
1539 				}
1540 			}
1541 			if (!tty_insert_flip_char(&port->port, ch, flag)) {
1542 				port->icount.buf_overrun++;
1543 				break;
1544 			}
1545 		}
1546 
1547 		if (hwid)
1548 			break;
1549 
1550 		status = inb(port->ioaddr + UART_LSR);
1551 	} while (status & UART_LSR_DR);
1552 
1553 	return status;
1554 }
1555 
1556 static u8 mxser_receive_chars(struct tty_struct *tty,
1557 		struct mxser_port *port, u8 status)
1558 {
1559 	if (!mxser_receive_chars_new(port, status))
1560 		status = mxser_receive_chars_old(tty, port, status);
1561 
1562 	tty_flip_buffer_push(&port->port);
1563 
1564 	return status;
1565 }
1566 
1567 static void mxser_transmit_chars(struct tty_struct *tty, struct mxser_port *port)
1568 {
1569 	int count;
1570 
1571 	if (port->x_char) {
1572 		outb(port->x_char, port->ioaddr + UART_TX);
1573 		port->x_char = 0;
1574 		port->icount.tx++;
1575 		return;
1576 	}
1577 
1578 	if (kfifo_is_empty(&port->port.xmit_fifo) || tty->flow.stopped ||
1579 			(tty->hw_stopped && !mxser_16550A_or_MUST(port))) {
1580 		__mxser_stop_tx(port);
1581 		return;
1582 	}
1583 
1584 	count = port->xmit_fifo_size;
1585 	do {
1586 		unsigned char c;
1587 
1588 		if (!kfifo_get(&port->port.xmit_fifo, &c))
1589 			break;
1590 
1591 		outb(c, port->ioaddr + UART_TX);
1592 		port->icount.tx++;
1593 	} while (--count > 0);
1594 
1595 	if (kfifo_len(&port->port.xmit_fifo) < WAKEUP_CHARS)
1596 		tty_wakeup(tty);
1597 
1598 	if (kfifo_is_empty(&port->port.xmit_fifo))
1599 		__mxser_stop_tx(port);
1600 }
1601 
1602 static bool mxser_port_isr(struct mxser_port *port)
1603 {
1604 	struct tty_struct *tty;
1605 	u8 iir, status;
1606 	bool error = false;
1607 
1608 	iir = inb(port->ioaddr + UART_IIR);
1609 	if (iir & UART_IIR_NO_INT)
1610 		return true;
1611 
1612 	iir &= MOXA_MUST_IIR_MASK;
1613 	tty = tty_port_tty_get(&port->port);
1614 	if (!tty) {
1615 		status = inb(port->ioaddr + UART_LSR);
1616 		outb(port->FCR | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT,
1617 				port->ioaddr + UART_FCR);
1618 		inb(port->ioaddr + UART_MSR);
1619 
1620 		error = true;
1621 		goto put_tty;
1622 	}
1623 
1624 	status = inb(port->ioaddr + UART_LSR);
1625 
1626 	if (port->board->must_hwid) {
1627 		if (iir == MOXA_MUST_IIR_GDA ||
1628 		    iir == MOXA_MUST_IIR_RDA ||
1629 		    iir == MOXA_MUST_IIR_RTO ||
1630 		    iir == MOXA_MUST_IIR_LSR)
1631 			status = mxser_receive_chars(tty, port, status);
1632 	} else {
1633 		status &= port->read_status_mask;
1634 		if (status & UART_LSR_DR)
1635 			status = mxser_receive_chars(tty, port, status);
1636 	}
1637 
1638 	mxser_check_modem_status(tty, port);
1639 
1640 	if (port->board->must_hwid) {
1641 		if (iir == 0x02 && (status & UART_LSR_THRE))
1642 			mxser_transmit_chars(tty, port);
1643 	} else {
1644 		if (status & UART_LSR_THRE)
1645 			mxser_transmit_chars(tty, port);
1646 	}
1647 
1648 put_tty:
1649 	tty_kref_put(tty);
1650 
1651 	return error;
1652 }
1653 
1654 /*
1655  * This is the serial driver's generic interrupt routine
1656  */
1657 static irqreturn_t mxser_interrupt(int irq, void *dev_id)
1658 {
1659 	struct mxser_board *brd = dev_id;
1660 	struct mxser_port *port;
1661 	unsigned int int_cnt, pass_counter = 0;
1662 	unsigned int i, max = brd->nports;
1663 	int handled = IRQ_NONE;
1664 	u8 irqbits, bits, mask = BIT(max) - 1;
1665 
1666 	while (pass_counter++ < MXSER_ISR_PASS_LIMIT) {
1667 		irqbits = inb(brd->vector) & mask;
1668 		if (irqbits == mask)
1669 			break;
1670 
1671 		handled = IRQ_HANDLED;
1672 		for (i = 0, bits = 1; i < max; i++, irqbits |= bits, bits <<= 1) {
1673 			if (irqbits == mask)
1674 				break;
1675 			if (bits & irqbits)
1676 				continue;
1677 			port = &brd->ports[i];
1678 
1679 			int_cnt = 0;
1680 			spin_lock(&port->slock);
1681 			do {
1682 				if (mxser_port_isr(port))
1683 					break;
1684 			} while (int_cnt++ < MXSER_ISR_PASS_LIMIT);
1685 			spin_unlock(&port->slock);
1686 		}
1687 	}
1688 
1689 	return handled;
1690 }
1691 
1692 static const struct tty_operations mxser_ops = {
1693 	.open = mxser_open,
1694 	.close = mxser_close,
1695 	.write = mxser_write,
1696 	.put_char = mxser_put_char,
1697 	.flush_chars = mxser_flush_chars,
1698 	.write_room = mxser_write_room,
1699 	.chars_in_buffer = mxser_chars_in_buffer,
1700 	.flush_buffer = mxser_flush_buffer,
1701 	.ioctl = mxser_ioctl,
1702 	.throttle = mxser_throttle,
1703 	.unthrottle = mxser_unthrottle,
1704 	.set_termios = mxser_set_termios,
1705 	.stop = mxser_stop,
1706 	.start = mxser_start,
1707 	.hangup = mxser_hangup,
1708 	.break_ctl = mxser_rs_break,
1709 	.wait_until_sent = mxser_wait_until_sent,
1710 	.tiocmget = mxser_tiocmget,
1711 	.tiocmset = mxser_tiocmset,
1712 	.set_serial = mxser_set_serial_info,
1713 	.get_serial = mxser_get_serial_info,
1714 	.get_icount = mxser_get_icount,
1715 };
1716 
1717 static const struct tty_port_operations mxser_port_ops = {
1718 	.carrier_raised = mxser_carrier_raised,
1719 	.dtr_rts = mxser_dtr_rts,
1720 	.activate = mxser_activate,
1721 	.shutdown = mxser_shutdown_port,
1722 };
1723 
1724 /*
1725  * The MOXA Smartio/Industio serial driver boot-time initialization code!
1726  */
1727 
1728 static void mxser_initbrd(struct mxser_board *brd, bool high_baud)
1729 {
1730 	struct mxser_port *info;
1731 	unsigned int i;
1732 	bool is_mu860;
1733 
1734 	brd->must_hwid = mxser_must_get_hwid(brd->ports[0].ioaddr);
1735 	is_mu860 = brd->must_hwid == MOXA_MUST_MU860_HWID;
1736 
1737 	for (i = 0; i < UART_INFO_NUM; i++) {
1738 		if (Gpci_uart_info[i].type == brd->must_hwid) {
1739 			brd->max_baud = Gpci_uart_info[i].max_baud;
1740 
1741 			/* exception....CP-102 */
1742 			if (high_baud)
1743 				brd->max_baud = 921600;
1744 			break;
1745 		}
1746 	}
1747 
1748 	if (is_mu860) {
1749 		/* set to RS232 mode by default */
1750 		outb(0, brd->vector + 4);
1751 		outb(0, brd->vector + 0x0c);
1752 	}
1753 
1754 	for (i = 0; i < brd->nports; i++) {
1755 		info = &brd->ports[i];
1756 		if (is_mu860) {
1757 			if (i < 4)
1758 				info->opmode_ioaddr = brd->vector + 4;
1759 			else
1760 				info->opmode_ioaddr = brd->vector + 0x0c;
1761 		}
1762 		tty_port_init(&info->port);
1763 		info->port.ops = &mxser_port_ops;
1764 		info->board = brd;
1765 
1766 		/* Enhance mode enabled here */
1767 		if (brd->must_hwid != MOXA_OTHER_UART)
1768 			mxser_must_set_enhance_mode(info->ioaddr, true);
1769 
1770 		info->type = PORT_16550A;
1771 
1772 		mxser_process_txrx_fifo(info);
1773 
1774 		info->port.close_delay = 5 * HZ / 10;
1775 		info->port.closing_wait = 30 * HZ;
1776 		spin_lock_init(&info->slock);
1777 
1778 		/* before set INT ISR, disable all int */
1779 		outb(inb(info->ioaddr + UART_IER) & 0xf0,
1780 			info->ioaddr + UART_IER);
1781 	}
1782 }
1783 
1784 static int mxser_probe(struct pci_dev *pdev,
1785 		const struct pci_device_id *ent)
1786 {
1787 	struct mxser_board *brd;
1788 	unsigned int i, base;
1789 	unsigned long ioaddress;
1790 	unsigned short nports = MXSER_NPORTS(ent->driver_data);
1791 	struct device *tty_dev;
1792 	int retval = -EINVAL;
1793 
1794 	i = find_first_zero_bit(mxser_boards, MXSER_BOARDS);
1795 	if (i >= MXSER_BOARDS) {
1796 		dev_err(&pdev->dev, "too many boards found (maximum %d), board "
1797 				"not configured\n", MXSER_BOARDS);
1798 		goto err;
1799 	}
1800 
1801 	brd = devm_kzalloc(&pdev->dev, struct_size(brd, ports, nports),
1802 			GFP_KERNEL);
1803 	if (!brd)
1804 		goto err;
1805 
1806 	brd->idx = i;
1807 	__set_bit(brd->idx, mxser_boards);
1808 	base = i * MXSER_PORTS_PER_BOARD;
1809 
1810 	retval = pcim_enable_device(pdev);
1811 	if (retval) {
1812 		dev_err(&pdev->dev, "PCI enable failed\n");
1813 		goto err_zero;
1814 	}
1815 
1816 	/* io address */
1817 	ioaddress = pci_resource_start(pdev, 2);
1818 	retval = pci_request_region(pdev, 2, "mxser(IO)");
1819 	if (retval)
1820 		goto err_zero;
1821 
1822 	brd->nports = nports;
1823 	for (i = 0; i < nports; i++)
1824 		brd->ports[i].ioaddr = ioaddress + 8 * i;
1825 
1826 	/* vector */
1827 	ioaddress = pci_resource_start(pdev, 3);
1828 	retval = pci_request_region(pdev, 3, "mxser(vector)");
1829 	if (retval)
1830 		goto err_zero;
1831 	brd->vector = ioaddress;
1832 
1833 	/* irq */
1834 	brd->irq = pdev->irq;
1835 
1836 	mxser_initbrd(brd, ent->driver_data & MXSER_HIGHBAUD);
1837 
1838 	retval = devm_request_irq(&pdev->dev, brd->irq, mxser_interrupt,
1839 			IRQF_SHARED, "mxser", brd);
1840 	if (retval) {
1841 		dev_err(&pdev->dev, "request irq failed");
1842 		goto err_relbrd;
1843 	}
1844 
1845 	for (i = 0; i < nports; i++) {
1846 		tty_dev = tty_port_register_device(&brd->ports[i].port,
1847 				mxvar_sdriver, base + i, &pdev->dev);
1848 		if (IS_ERR(tty_dev)) {
1849 			retval = PTR_ERR(tty_dev);
1850 			for (; i > 0; i--)
1851 				tty_unregister_device(mxvar_sdriver,
1852 					base + i - 1);
1853 			goto err_relbrd;
1854 		}
1855 	}
1856 
1857 	pci_set_drvdata(pdev, brd);
1858 
1859 	return 0;
1860 err_relbrd:
1861 	for (i = 0; i < nports; i++)
1862 		tty_port_destroy(&brd->ports[i].port);
1863 err_zero:
1864 	__clear_bit(brd->idx, mxser_boards);
1865 err:
1866 	return retval;
1867 }
1868 
1869 static void mxser_remove(struct pci_dev *pdev)
1870 {
1871 	struct mxser_board *brd = pci_get_drvdata(pdev);
1872 	unsigned int i, base = brd->idx * MXSER_PORTS_PER_BOARD;
1873 
1874 	for (i = 0; i < brd->nports; i++) {
1875 		tty_unregister_device(mxvar_sdriver, base + i);
1876 		tty_port_destroy(&brd->ports[i].port);
1877 	}
1878 
1879 	__clear_bit(brd->idx, mxser_boards);
1880 }
1881 
1882 static struct pci_driver mxser_driver = {
1883 	.name = "mxser",
1884 	.id_table = mxser_pcibrds,
1885 	.probe = mxser_probe,
1886 	.remove = mxser_remove
1887 };
1888 
1889 static int __init mxser_module_init(void)
1890 {
1891 	int retval;
1892 
1893 	mxvar_sdriver = tty_alloc_driver(MXSER_PORTS, TTY_DRIVER_REAL_RAW |
1894 			TTY_DRIVER_DYNAMIC_DEV);
1895 	if (IS_ERR(mxvar_sdriver))
1896 		return PTR_ERR(mxvar_sdriver);
1897 
1898 	/* Initialize the tty_driver structure */
1899 	mxvar_sdriver->name = "ttyMI";
1900 	mxvar_sdriver->major = ttymajor;
1901 	mxvar_sdriver->minor_start = 0;
1902 	mxvar_sdriver->type = TTY_DRIVER_TYPE_SERIAL;
1903 	mxvar_sdriver->subtype = SERIAL_TYPE_NORMAL;
1904 	mxvar_sdriver->init_termios = tty_std_termios;
1905 	mxvar_sdriver->init_termios.c_cflag = B9600|CS8|CREAD|HUPCL|CLOCAL;
1906 	tty_set_operations(mxvar_sdriver, &mxser_ops);
1907 
1908 	retval = tty_register_driver(mxvar_sdriver);
1909 	if (retval) {
1910 		printk(KERN_ERR "Couldn't install MOXA Smartio/Industio family "
1911 				"tty driver !\n");
1912 		goto err_put;
1913 	}
1914 
1915 	retval = pci_register_driver(&mxser_driver);
1916 	if (retval) {
1917 		printk(KERN_ERR "mxser: can't register pci driver\n");
1918 		goto err_unr;
1919 	}
1920 
1921 	return 0;
1922 err_unr:
1923 	tty_unregister_driver(mxvar_sdriver);
1924 err_put:
1925 	tty_driver_kref_put(mxvar_sdriver);
1926 	return retval;
1927 }
1928 
1929 static void __exit mxser_module_exit(void)
1930 {
1931 	pci_unregister_driver(&mxser_driver);
1932 	tty_unregister_driver(mxvar_sdriver);
1933 	tty_driver_kref_put(mxvar_sdriver);
1934 }
1935 
1936 module_init(mxser_module_init);
1937 module_exit(mxser_module_exit);
1938