xref: /openbmc/linux/drivers/usb/serial/mos7720.c (revision 97da55fc)
1 /*
2  * mos7720.c
3  *   Controls the Moschip 7720 usb to dual port serial convertor
4  *
5  * Copyright 2006 Moschip Semiconductor Tech. Ltd.
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation, version 2 of the License.
10  *
11  * Developed by:
12  * 	Vijaya Kumar <vijaykumar.gn@gmail.com>
13  *	Ajay Kumar <naanuajay@yahoo.com>
14  *	Gurudeva <ngurudeva@yahoo.com>
15  *
16  * Cleaned up from the original by:
17  *	Greg Kroah-Hartman <gregkh@suse.de>
18  *
19  * Originally based on drivers/usb/serial/io_edgeport.c which is:
20  *	Copyright (C) 2000 Inside Out Networks, All rights reserved.
21  *	Copyright (C) 2001-2002 Greg Kroah-Hartman <greg@kroah.com>
22  */
23 #include <linux/kernel.h>
24 #include <linux/errno.h>
25 #include <linux/init.h>
26 #include <linux/slab.h>
27 #include <linux/tty.h>
28 #include <linux/tty_driver.h>
29 #include <linux/tty_flip.h>
30 #include <linux/module.h>
31 #include <linux/spinlock.h>
32 #include <linux/serial.h>
33 #include <linux/serial_reg.h>
34 #include <linux/usb.h>
35 #include <linux/usb/serial.h>
36 #include <linux/uaccess.h>
37 #include <linux/parport.h>
38 
39 #define DRIVER_AUTHOR "Aspire Communications pvt Ltd."
40 #define DRIVER_DESC "Moschip USB Serial Driver"
41 
42 /* default urb timeout */
43 #define MOS_WDR_TIMEOUT	(HZ * 5)
44 
45 #define MOS_MAX_PORT	0x02
46 #define MOS_WRITE	0x0E
47 #define MOS_READ	0x0D
48 
49 /* Interrupt Rotinue Defines	*/
50 #define SERIAL_IIR_RLS	0x06
51 #define SERIAL_IIR_RDA	0x04
52 #define SERIAL_IIR_CTI	0x0c
53 #define SERIAL_IIR_THR	0x02
54 #define SERIAL_IIR_MS	0x00
55 
56 #define NUM_URBS			16	/* URB Count */
57 #define URB_TRANSFER_BUFFER_SIZE	32	/* URB Size */
58 
59 /* This structure holds all of the local serial port information */
60 struct moschip_port {
61 	__u8	shadowLCR;		/* last LCR value received */
62 	__u8	shadowMCR;		/* last MCR value received */
63 	__u8	shadowMSR;		/* last MSR value received */
64 	char			open;
65 	struct async_icount	icount;
66 	struct usb_serial_port	*port;	/* loop back to the owner */
67 	struct urb		*write_urb_pool[NUM_URBS];
68 };
69 
70 static struct usb_serial_driver moschip7720_2port_driver;
71 
72 #define USB_VENDOR_ID_MOSCHIP		0x9710
73 #define MOSCHIP_DEVICE_ID_7720		0x7720
74 #define MOSCHIP_DEVICE_ID_7715		0x7715
75 
76 static const struct usb_device_id id_table[] = {
77 	{ USB_DEVICE(USB_VENDOR_ID_MOSCHIP, MOSCHIP_DEVICE_ID_7720) },
78 	{ USB_DEVICE(USB_VENDOR_ID_MOSCHIP, MOSCHIP_DEVICE_ID_7715) },
79 	{ } /* terminating entry */
80 };
81 MODULE_DEVICE_TABLE(usb, id_table);
82 
83 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
84 
85 /* initial values for parport regs */
86 #define DCR_INIT_VAL       0x0c	/* SLCTIN, nINIT */
87 #define ECR_INIT_VAL       0x00	/* SPP mode */
88 
89 struct urbtracker {
90 	struct mos7715_parport  *mos_parport;
91 	struct list_head        urblist_entry;
92 	struct kref             ref_count;
93 	struct urb              *urb;
94 };
95 
96 enum mos7715_pp_modes {
97 	SPP = 0<<5,
98 	PS2 = 1<<5,      /* moschip calls this 'NIBBLE' mode */
99 	PPF = 2<<5,	 /* moschip calls this 'CB-FIFO mode */
100 };
101 
102 struct mos7715_parport {
103 	struct parport          *pp;	       /* back to containing struct */
104 	struct kref             ref_count;     /* to instance of this struct */
105 	struct list_head        deferred_urbs; /* list deferred async urbs */
106 	struct list_head        active_urbs;   /* list async urbs in flight */
107 	spinlock_t              listlock;      /* protects list access */
108 	bool                    msg_pending;   /* usb sync call pending */
109 	struct completion       syncmsg_compl; /* usb sync call completed */
110 	struct tasklet_struct   urb_tasklet;   /* for sending deferred urbs */
111 	struct usb_serial       *serial;       /* back to containing struct */
112 	__u8	                shadowECR;     /* parallel port regs... */
113 	__u8	                shadowDCR;
114 	atomic_t                shadowDSR;     /* updated in int-in callback */
115 };
116 
117 /* lock guards against dereferencing NULL ptr in parport ops callbacks */
118 static DEFINE_SPINLOCK(release_lock);
119 
120 #endif	/* CONFIG_USB_SERIAL_MOS7715_PARPORT */
121 
122 static const unsigned int dummy; /* for clarity in register access fns */
123 
124 enum mos_regs {
125 	THR,	          /* serial port regs */
126 	RHR,
127 	IER,
128 	FCR,
129 	ISR,
130 	LCR,
131 	MCR,
132 	LSR,
133 	MSR,
134 	SPR,
135 	DLL,
136 	DLM,
137 	DPR,              /* parallel port regs */
138 	DSR,
139 	DCR,
140 	ECR,
141 	SP1_REG,          /* device control regs */
142 	SP2_REG,          /* serial port 2 (7720 only) */
143 	PP_REG,
144 	SP_CONTROL_REG,
145 };
146 
147 /*
148  * Return the correct value for the Windex field of the setup packet
149  * for a control endpoint message.  See the 7715 datasheet.
150  */
151 static inline __u16 get_reg_index(enum mos_regs reg)
152 {
153 	static const __u16 mos7715_index_lookup_table[] = {
154 		0x00,		/* THR */
155 		0x00,		/* RHR */
156 		0x01,		/* IER */
157 		0x02,		/* FCR */
158 		0x02,		/* ISR */
159 		0x03,		/* LCR */
160 		0x04,		/* MCR */
161 		0x05,		/* LSR */
162 		0x06,		/* MSR */
163 		0x07,		/* SPR */
164 		0x00,		/* DLL */
165 		0x01,		/* DLM */
166 		0x00,		/* DPR */
167 		0x01,		/* DSR */
168 		0x02,		/* DCR */
169 		0x0a,		/* ECR */
170 		0x01,		/* SP1_REG */
171 		0x02,		/* SP2_REG (7720 only) */
172 		0x04,		/* PP_REG (7715 only) */
173 		0x08,		/* SP_CONTROL_REG */
174 	};
175 	return mos7715_index_lookup_table[reg];
176 }
177 
178 /*
179  * Return the correct value for the upper byte of the Wvalue field of
180  * the setup packet for a control endpoint message.
181  */
182 static inline __u16 get_reg_value(enum mos_regs reg,
183 				  unsigned int serial_portnum)
184 {
185 	if (reg >= SP1_REG)	      /* control reg */
186 		return 0x0000;
187 
188 	else if (reg >= DPR)	      /* parallel port reg (7715 only) */
189 		return 0x0100;
190 
191 	else			      /* serial port reg */
192 		return (serial_portnum + 2) << 8;
193 }
194 
195 /*
196  * Write data byte to the specified device register.  The data is embedded in
197  * the value field of the setup packet. serial_portnum is ignored for registers
198  * not specific to a particular serial port.
199  */
200 static int write_mos_reg(struct usb_serial *serial, unsigned int serial_portnum,
201 			 enum mos_regs reg, __u8 data)
202 {
203 	struct usb_device *usbdev = serial->dev;
204 	unsigned int pipe = usb_sndctrlpipe(usbdev, 0);
205 	__u8 request = (__u8)0x0e;
206 	__u8 requesttype = (__u8)0x40;
207 	__u16 index = get_reg_index(reg);
208 	__u16 value = get_reg_value(reg, serial_portnum) + data;
209 	int status = usb_control_msg(usbdev, pipe, request, requesttype, value,
210 				     index, NULL, 0, MOS_WDR_TIMEOUT);
211 	if (status < 0)
212 		dev_err(&usbdev->dev,
213 			"mos7720: usb_control_msg() failed: %d", status);
214 	return status;
215 }
216 
217 /*
218  * Read data byte from the specified device register.  The data returned by the
219  * device is embedded in the value field of the setup packet.  serial_portnum is
220  * ignored for registers that are not specific to a particular serial port.
221  */
222 static int read_mos_reg(struct usb_serial *serial, unsigned int serial_portnum,
223 			enum mos_regs reg, __u8 *data)
224 {
225 	struct usb_device *usbdev = serial->dev;
226 	unsigned int pipe = usb_rcvctrlpipe(usbdev, 0);
227 	__u8 request = (__u8)0x0d;
228 	__u8 requesttype = (__u8)0xc0;
229 	__u16 index = get_reg_index(reg);
230 	__u16 value = get_reg_value(reg, serial_portnum);
231 	int status = usb_control_msg(usbdev, pipe, request, requesttype, value,
232 				     index, data, 1, MOS_WDR_TIMEOUT);
233 	if (status < 0)
234 		dev_err(&usbdev->dev,
235 			"mos7720: usb_control_msg() failed: %d", status);
236 	return status;
237 }
238 
239 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
240 
241 static inline int mos7715_change_mode(struct mos7715_parport *mos_parport,
242 				      enum mos7715_pp_modes mode)
243 {
244 	mos_parport->shadowECR = mode;
245 	write_mos_reg(mos_parport->serial, dummy, ECR, mos_parport->shadowECR);
246 	return 0;
247 }
248 
249 static void destroy_mos_parport(struct kref *kref)
250 {
251 	struct mos7715_parport *mos_parport =
252 		container_of(kref, struct mos7715_parport, ref_count);
253 
254 	kfree(mos_parport);
255 }
256 
257 static void destroy_urbtracker(struct kref *kref)
258 {
259 	struct urbtracker *urbtrack =
260 		container_of(kref, struct urbtracker, ref_count);
261 	struct mos7715_parport *mos_parport = urbtrack->mos_parport;
262 
263 	usb_free_urb(urbtrack->urb);
264 	kfree(urbtrack);
265 	kref_put(&mos_parport->ref_count, destroy_mos_parport);
266 }
267 
268 /*
269  * This runs as a tasklet when sending an urb in a non-blocking parallel
270  * port callback had to be deferred because the disconnect mutex could not be
271  * obtained at the time.
272  */
273 static void send_deferred_urbs(unsigned long _mos_parport)
274 {
275 	int ret_val;
276 	unsigned long flags;
277 	struct mos7715_parport *mos_parport = (void *)_mos_parport;
278 	struct urbtracker *urbtrack, *tmp;
279 	struct list_head *cursor, *next;
280 	struct device *dev;
281 
282 	/* if release function ran, game over */
283 	if (unlikely(mos_parport->serial == NULL))
284 		return;
285 
286 	dev = &mos_parport->serial->dev->dev;
287 
288 	/* try again to get the mutex */
289 	if (!mutex_trylock(&mos_parport->serial->disc_mutex)) {
290 		dev_dbg(dev, "%s: rescheduling tasklet\n", __func__);
291 		tasklet_schedule(&mos_parport->urb_tasklet);
292 		return;
293 	}
294 
295 	/* if device disconnected, game over */
296 	if (unlikely(mos_parport->serial->disconnected)) {
297 		mutex_unlock(&mos_parport->serial->disc_mutex);
298 		return;
299 	}
300 
301 	spin_lock_irqsave(&mos_parport->listlock, flags);
302 	if (list_empty(&mos_parport->deferred_urbs)) {
303 		spin_unlock_irqrestore(&mos_parport->listlock, flags);
304 		mutex_unlock(&mos_parport->serial->disc_mutex);
305 		dev_dbg(dev, "%s: deferred_urbs list empty\n", __func__);
306 		return;
307 	}
308 
309 	/* move contents of deferred_urbs list to active_urbs list and submit */
310 	list_for_each_safe(cursor, next, &mos_parport->deferred_urbs)
311 		list_move_tail(cursor, &mos_parport->active_urbs);
312 	list_for_each_entry_safe(urbtrack, tmp, &mos_parport->active_urbs,
313 			    urblist_entry) {
314 		ret_val = usb_submit_urb(urbtrack->urb, GFP_ATOMIC);
315 		dev_dbg(dev, "%s: urb submitted\n", __func__);
316 		if (ret_val) {
317 			dev_err(dev, "usb_submit_urb() failed: %d\n", ret_val);
318 			list_del(&urbtrack->urblist_entry);
319 			kref_put(&urbtrack->ref_count, destroy_urbtracker);
320 		}
321 	}
322 	spin_unlock_irqrestore(&mos_parport->listlock, flags);
323 	mutex_unlock(&mos_parport->serial->disc_mutex);
324 }
325 
326 /* callback for parallel port control urbs submitted asynchronously */
327 static void async_complete(struct urb *urb)
328 {
329 	struct urbtracker *urbtrack = urb->context;
330 	int status = urb->status;
331 
332 	if (unlikely(status))
333 		dev_dbg(&urb->dev->dev, "%s - nonzero urb status received: %d\n", __func__, status);
334 
335 	/* remove the urbtracker from the active_urbs list */
336 	spin_lock(&urbtrack->mos_parport->listlock);
337 	list_del(&urbtrack->urblist_entry);
338 	spin_unlock(&urbtrack->mos_parport->listlock);
339 	kref_put(&urbtrack->ref_count, destroy_urbtracker);
340 }
341 
342 static int write_parport_reg_nonblock(struct mos7715_parport *mos_parport,
343 				      enum mos_regs reg, __u8 data)
344 {
345 	struct urbtracker *urbtrack;
346 	int ret_val;
347 	unsigned long flags;
348 	struct usb_ctrlrequest setup;
349 	struct usb_serial *serial = mos_parport->serial;
350 	struct usb_device *usbdev = serial->dev;
351 
352 	/* create and initialize the control urb and containing urbtracker */
353 	urbtrack = kmalloc(sizeof(struct urbtracker), GFP_ATOMIC);
354 	if (urbtrack == NULL) {
355 		dev_err(&usbdev->dev, "out of memory");
356 		return -ENOMEM;
357 	}
358 	kref_get(&mos_parport->ref_count);
359 	urbtrack->mos_parport = mos_parport;
360 	urbtrack->urb = usb_alloc_urb(0, GFP_ATOMIC);
361 	if (urbtrack->urb == NULL) {
362 		dev_err(&usbdev->dev, "out of urbs");
363 		kfree(urbtrack);
364 		return -ENOMEM;
365 	}
366 	setup.bRequestType = (__u8)0x40;
367 	setup.bRequest = (__u8)0x0e;
368 	setup.wValue = get_reg_value(reg, dummy);
369 	setup.wIndex = get_reg_index(reg);
370 	setup.wLength = 0;
371 	usb_fill_control_urb(urbtrack->urb, usbdev,
372 			     usb_sndctrlpipe(usbdev, 0),
373 			     (unsigned char *)&setup,
374 			     NULL, 0, async_complete, urbtrack);
375 	kref_init(&urbtrack->ref_count);
376 	INIT_LIST_HEAD(&urbtrack->urblist_entry);
377 
378 	/*
379 	 * get the disconnect mutex, or add tracker to the deferred_urbs list
380 	 * and schedule a tasklet to try again later
381 	 */
382 	if (!mutex_trylock(&serial->disc_mutex)) {
383 		spin_lock_irqsave(&mos_parport->listlock, flags);
384 		list_add_tail(&urbtrack->urblist_entry,
385 			      &mos_parport->deferred_urbs);
386 		spin_unlock_irqrestore(&mos_parport->listlock, flags);
387 		tasklet_schedule(&mos_parport->urb_tasklet);
388 		dev_dbg(&usbdev->dev, "tasklet scheduled");
389 		return 0;
390 	}
391 
392 	/* bail if device disconnected */
393 	if (serial->disconnected) {
394 		kref_put(&urbtrack->ref_count, destroy_urbtracker);
395 		mutex_unlock(&serial->disc_mutex);
396 		return -ENODEV;
397 	}
398 
399 	/* add the tracker to the active_urbs list and submit */
400 	spin_lock_irqsave(&mos_parport->listlock, flags);
401 	list_add_tail(&urbtrack->urblist_entry, &mos_parport->active_urbs);
402 	spin_unlock_irqrestore(&mos_parport->listlock, flags);
403 	ret_val = usb_submit_urb(urbtrack->urb, GFP_ATOMIC);
404 	mutex_unlock(&serial->disc_mutex);
405 	if (ret_val) {
406 		dev_err(&usbdev->dev,
407 			"%s: submit_urb() failed: %d", __func__, ret_val);
408 		spin_lock_irqsave(&mos_parport->listlock, flags);
409 		list_del(&urbtrack->urblist_entry);
410 		spin_unlock_irqrestore(&mos_parport->listlock, flags);
411 		kref_put(&urbtrack->ref_count, destroy_urbtracker);
412 		return ret_val;
413 	}
414 	return 0;
415 }
416 
417 /*
418  * This is the the common top part of all parallel port callback operations that
419  * send synchronous messages to the device.  This implements convoluted locking
420  * that avoids two scenarios: (1) a port operation is called after usbserial
421  * has called our release function, at which point struct mos7715_parport has
422  * been destroyed, and (2) the device has been disconnected, but usbserial has
423  * not called the release function yet because someone has a serial port open.
424  * The shared release_lock prevents the first, and the mutex and disconnected
425  * flag maintained by usbserial covers the second.  We also use the msg_pending
426  * flag to ensure that all synchronous usb messgage calls have completed before
427  * our release function can return.
428  */
429 static int parport_prologue(struct parport *pp)
430 {
431 	struct mos7715_parport *mos_parport;
432 
433 	spin_lock(&release_lock);
434 	mos_parport = pp->private_data;
435 	if (unlikely(mos_parport == NULL)) {
436 		/* release fn called, port struct destroyed */
437 		spin_unlock(&release_lock);
438 		return -1;
439 	}
440 	mos_parport->msg_pending = true;   /* synch usb call pending */
441 	INIT_COMPLETION(mos_parport->syncmsg_compl);
442 	spin_unlock(&release_lock);
443 
444 	mutex_lock(&mos_parport->serial->disc_mutex);
445 	if (mos_parport->serial->disconnected) {
446 		/* device disconnected */
447 		mutex_unlock(&mos_parport->serial->disc_mutex);
448 		mos_parport->msg_pending = false;
449 		complete(&mos_parport->syncmsg_compl);
450 		return -1;
451 	}
452 
453 	return 0;
454 }
455 
456 /*
457  * This is the the common bottom part of all parallel port functions that send
458  * synchronous messages to the device.
459  */
460 static inline void parport_epilogue(struct parport *pp)
461 {
462 	struct mos7715_parport *mos_parport = pp->private_data;
463 	mutex_unlock(&mos_parport->serial->disc_mutex);
464 	mos_parport->msg_pending = false;
465 	complete(&mos_parport->syncmsg_compl);
466 }
467 
468 static void parport_mos7715_write_data(struct parport *pp, unsigned char d)
469 {
470 	struct mos7715_parport *mos_parport = pp->private_data;
471 
472 	if (parport_prologue(pp) < 0)
473 		return;
474 	mos7715_change_mode(mos_parport, SPP);
475 	write_mos_reg(mos_parport->serial, dummy, DPR, (__u8)d);
476 	parport_epilogue(pp);
477 }
478 
479 static unsigned char parport_mos7715_read_data(struct parport *pp)
480 {
481 	struct mos7715_parport *mos_parport = pp->private_data;
482 	unsigned char d;
483 
484 	if (parport_prologue(pp) < 0)
485 		return 0;
486 	read_mos_reg(mos_parport->serial, dummy, DPR, &d);
487 	parport_epilogue(pp);
488 	return d;
489 }
490 
491 static void parport_mos7715_write_control(struct parport *pp, unsigned char d)
492 {
493 	struct mos7715_parport *mos_parport = pp->private_data;
494 	__u8 data;
495 
496 	if (parport_prologue(pp) < 0)
497 		return;
498 	data = ((__u8)d & 0x0f) | (mos_parport->shadowDCR & 0xf0);
499 	write_mos_reg(mos_parport->serial, dummy, DCR, data);
500 	mos_parport->shadowDCR = data;
501 	parport_epilogue(pp);
502 }
503 
504 static unsigned char parport_mos7715_read_control(struct parport *pp)
505 {
506 	struct mos7715_parport *mos_parport = pp->private_data;
507 	__u8 dcr;
508 
509 	spin_lock(&release_lock);
510 	mos_parport = pp->private_data;
511 	if (unlikely(mos_parport == NULL)) {
512 		spin_unlock(&release_lock);
513 		return 0;
514 	}
515 	dcr = mos_parport->shadowDCR & 0x0f;
516 	spin_unlock(&release_lock);
517 	return dcr;
518 }
519 
520 static unsigned char parport_mos7715_frob_control(struct parport *pp,
521 						  unsigned char mask,
522 						  unsigned char val)
523 {
524 	struct mos7715_parport *mos_parport = pp->private_data;
525 	__u8 dcr;
526 
527 	mask &= 0x0f;
528 	val &= 0x0f;
529 	if (parport_prologue(pp) < 0)
530 		return 0;
531 	mos_parport->shadowDCR = (mos_parport->shadowDCR & (~mask)) ^ val;
532 	write_mos_reg(mos_parport->serial, dummy, DCR, mos_parport->shadowDCR);
533 	dcr = mos_parport->shadowDCR & 0x0f;
534 	parport_epilogue(pp);
535 	return dcr;
536 }
537 
538 static unsigned char parport_mos7715_read_status(struct parport *pp)
539 {
540 	unsigned char status;
541 	struct mos7715_parport *mos_parport = pp->private_data;
542 
543 	spin_lock(&release_lock);
544 	mos_parport = pp->private_data;
545 	if (unlikely(mos_parport == NULL)) {	/* release called */
546 		spin_unlock(&release_lock);
547 		return 0;
548 	}
549 	status = atomic_read(&mos_parport->shadowDSR) & 0xf8;
550 	spin_unlock(&release_lock);
551 	return status;
552 }
553 
554 static void parport_mos7715_enable_irq(struct parport *pp)
555 {
556 }
557 
558 static void parport_mos7715_disable_irq(struct parport *pp)
559 {
560 }
561 
562 static void parport_mos7715_data_forward(struct parport *pp)
563 {
564 	struct mos7715_parport *mos_parport = pp->private_data;
565 
566 	if (parport_prologue(pp) < 0)
567 		return;
568 	mos7715_change_mode(mos_parport, PS2);
569 	mos_parport->shadowDCR &=  ~0x20;
570 	write_mos_reg(mos_parport->serial, dummy, DCR, mos_parport->shadowDCR);
571 	parport_epilogue(pp);
572 }
573 
574 static void parport_mos7715_data_reverse(struct parport *pp)
575 {
576 	struct mos7715_parport *mos_parport = pp->private_data;
577 
578 	if (parport_prologue(pp) < 0)
579 		return;
580 	mos7715_change_mode(mos_parport, PS2);
581 	mos_parport->shadowDCR |= 0x20;
582 	write_mos_reg(mos_parport->serial, dummy, DCR, mos_parport->shadowDCR);
583 	parport_epilogue(pp);
584 }
585 
586 static void parport_mos7715_init_state(struct pardevice *dev,
587 				       struct parport_state *s)
588 {
589 	s->u.pc.ctr = DCR_INIT_VAL;
590 	s->u.pc.ecr = ECR_INIT_VAL;
591 }
592 
593 /* N.B. Parport core code requires that this function not block */
594 static void parport_mos7715_save_state(struct parport *pp,
595 				       struct parport_state *s)
596 {
597 	struct mos7715_parport *mos_parport;
598 
599 	spin_lock(&release_lock);
600 	mos_parport = pp->private_data;
601 	if (unlikely(mos_parport == NULL)) {	/* release called */
602 		spin_unlock(&release_lock);
603 		return;
604 	}
605 	s->u.pc.ctr = mos_parport->shadowDCR;
606 	s->u.pc.ecr = mos_parport->shadowECR;
607 	spin_unlock(&release_lock);
608 }
609 
610 /* N.B. Parport core code requires that this function not block */
611 static void parport_mos7715_restore_state(struct parport *pp,
612 					  struct parport_state *s)
613 {
614 	struct mos7715_parport *mos_parport;
615 
616 	spin_lock(&release_lock);
617 	mos_parport = pp->private_data;
618 	if (unlikely(mos_parport == NULL)) {	/* release called */
619 		spin_unlock(&release_lock);
620 		return;
621 	}
622 	write_parport_reg_nonblock(mos_parport, DCR, mos_parport->shadowDCR);
623 	write_parport_reg_nonblock(mos_parport, ECR, mos_parport->shadowECR);
624 	spin_unlock(&release_lock);
625 }
626 
627 static size_t parport_mos7715_write_compat(struct parport *pp,
628 					   const void *buffer,
629 					   size_t len, int flags)
630 {
631 	int retval;
632 	struct mos7715_parport *mos_parport = pp->private_data;
633 	int actual_len;
634 
635 	if (parport_prologue(pp) < 0)
636 		return 0;
637 	mos7715_change_mode(mos_parport, PPF);
638 	retval = usb_bulk_msg(mos_parport->serial->dev,
639 			      usb_sndbulkpipe(mos_parport->serial->dev, 2),
640 			      (void *)buffer, len, &actual_len,
641 			      MOS_WDR_TIMEOUT);
642 	parport_epilogue(pp);
643 	if (retval) {
644 		dev_err(&mos_parport->serial->dev->dev,
645 			"mos7720: usb_bulk_msg() failed: %d", retval);
646 		return 0;
647 	}
648 	return actual_len;
649 }
650 
651 static struct parport_operations parport_mos7715_ops = {
652 	.owner =		THIS_MODULE,
653 	.write_data =		parport_mos7715_write_data,
654 	.read_data =		parport_mos7715_read_data,
655 
656 	.write_control =	parport_mos7715_write_control,
657 	.read_control =		parport_mos7715_read_control,
658 	.frob_control =		parport_mos7715_frob_control,
659 
660 	.read_status =		parport_mos7715_read_status,
661 
662 	.enable_irq =		parport_mos7715_enable_irq,
663 	.disable_irq =		parport_mos7715_disable_irq,
664 
665 	.data_forward =		parport_mos7715_data_forward,
666 	.data_reverse =		parport_mos7715_data_reverse,
667 
668 	.init_state =		parport_mos7715_init_state,
669 	.save_state =		parport_mos7715_save_state,
670 	.restore_state =	parport_mos7715_restore_state,
671 
672 	.compat_write_data =	parport_mos7715_write_compat,
673 
674 	.nibble_read_data =	parport_ieee1284_read_nibble,
675 	.byte_read_data =	parport_ieee1284_read_byte,
676 };
677 
678 /*
679  * Allocate and initialize parallel port control struct, initialize
680  * the parallel port hardware device, and register with the parport subsystem.
681  */
682 static int mos7715_parport_init(struct usb_serial *serial)
683 {
684 	struct mos7715_parport *mos_parport;
685 
686 	/* allocate and initialize parallel port control struct */
687 	mos_parport = kzalloc(sizeof(struct mos7715_parport), GFP_KERNEL);
688 	if (mos_parport == NULL) {
689 		dev_dbg(&serial->dev->dev, "%s: kzalloc failed\n", __func__);
690 		return -ENOMEM;
691 	}
692 	mos_parport->msg_pending = false;
693 	kref_init(&mos_parport->ref_count);
694 	spin_lock_init(&mos_parport->listlock);
695 	INIT_LIST_HEAD(&mos_parport->active_urbs);
696 	INIT_LIST_HEAD(&mos_parport->deferred_urbs);
697 	usb_set_serial_data(serial, mos_parport); /* hijack private pointer */
698 	mos_parport->serial = serial;
699 	tasklet_init(&mos_parport->urb_tasklet, send_deferred_urbs,
700 		     (unsigned long) mos_parport);
701 	init_completion(&mos_parport->syncmsg_compl);
702 
703 	/* cycle parallel port reset bit */
704 	write_mos_reg(mos_parport->serial, dummy, PP_REG, (__u8)0x80);
705 	write_mos_reg(mos_parport->serial, dummy, PP_REG, (__u8)0x00);
706 
707 	/* initialize device registers */
708 	mos_parport->shadowDCR = DCR_INIT_VAL;
709 	write_mos_reg(mos_parport->serial, dummy, DCR, mos_parport->shadowDCR);
710 	mos_parport->shadowECR = ECR_INIT_VAL;
711 	write_mos_reg(mos_parport->serial, dummy, ECR, mos_parport->shadowECR);
712 
713 	/* register with parport core */
714 	mos_parport->pp = parport_register_port(0, PARPORT_IRQ_NONE,
715 						PARPORT_DMA_NONE,
716 						&parport_mos7715_ops);
717 	if (mos_parport->pp == NULL) {
718 		dev_err(&serial->interface->dev,
719 			"Could not register parport\n");
720 		kref_put(&mos_parport->ref_count, destroy_mos_parport);
721 		return -EIO;
722 	}
723 	mos_parport->pp->private_data = mos_parport;
724 	mos_parport->pp->modes = PARPORT_MODE_COMPAT | PARPORT_MODE_PCSPP;
725 	mos_parport->pp->dev = &serial->interface->dev;
726 	parport_announce_port(mos_parport->pp);
727 
728 	return 0;
729 }
730 #endif	/* CONFIG_USB_SERIAL_MOS7715_PARPORT */
731 
732 /*
733  * mos7720_interrupt_callback
734  *	this is the callback function for when we have received data on the
735  *	interrupt endpoint.
736  */
737 static void mos7720_interrupt_callback(struct urb *urb)
738 {
739 	int result;
740 	int length;
741 	int status = urb->status;
742 	struct device *dev = &urb->dev->dev;
743 	__u8 *data;
744 	__u8 sp1;
745 	__u8 sp2;
746 
747 	switch (status) {
748 	case 0:
749 		/* success */
750 		break;
751 	case -ECONNRESET:
752 	case -ENOENT:
753 	case -ESHUTDOWN:
754 		/* this urb is terminated, clean up */
755 		dev_dbg(dev, "%s - urb shutting down with status: %d\n", __func__, status);
756 		return;
757 	default:
758 		dev_dbg(dev, "%s - nonzero urb status received: %d\n", __func__, status);
759 		goto exit;
760 	}
761 
762 	length = urb->actual_length;
763 	data = urb->transfer_buffer;
764 
765 	/* Moschip get 4 bytes
766 	 * Byte 1 IIR Port 1 (port.number is 0)
767 	 * Byte 2 IIR Port 2 (port.number is 1)
768 	 * Byte 3 --------------
769 	 * Byte 4 FIFO status for both */
770 
771 	/* the above description is inverted
772 	 * 	oneukum 2007-03-14 */
773 
774 	if (unlikely(length != 4)) {
775 		dev_dbg(dev, "Wrong data !!!\n");
776 		return;
777 	}
778 
779 	sp1 = data[3];
780 	sp2 = data[2];
781 
782 	if ((sp1 | sp2) & 0x01) {
783 		/* No Interrupt Pending in both the ports */
784 		dev_dbg(dev, "No Interrupt !!!\n");
785 	} else {
786 		switch (sp1 & 0x0f) {
787 		case SERIAL_IIR_RLS:
788 			dev_dbg(dev, "Serial Port 1: Receiver status error or address bit detected in 9-bit mode\n");
789 			break;
790 		case SERIAL_IIR_CTI:
791 			dev_dbg(dev, "Serial Port 1: Receiver time out\n");
792 			break;
793 		case SERIAL_IIR_MS:
794 			/* dev_dbg(dev, "Serial Port 1: Modem status change\n"); */
795 			break;
796 		}
797 
798 		switch (sp2 & 0x0f) {
799 		case SERIAL_IIR_RLS:
800 			dev_dbg(dev, "Serial Port 2: Receiver status error or address bit detected in 9-bit mode\n");
801 			break;
802 		case SERIAL_IIR_CTI:
803 			dev_dbg(dev, "Serial Port 2: Receiver time out\n");
804 			break;
805 		case SERIAL_IIR_MS:
806 			/* dev_dbg(dev, "Serial Port 2: Modem status change\n"); */
807 			break;
808 		}
809 	}
810 
811 exit:
812 	result = usb_submit_urb(urb, GFP_ATOMIC);
813 	if (result)
814 		dev_err(dev, "%s - Error %d submitting control urb\n", __func__, result);
815 }
816 
817 /*
818  * mos7715_interrupt_callback
819  *	this is the 7715's callback function for when we have received data on
820  *	the interrupt endpoint.
821  */
822 static void mos7715_interrupt_callback(struct urb *urb)
823 {
824 	int result;
825 	int length;
826 	int status = urb->status;
827 	struct device *dev = &urb->dev->dev;
828 	__u8 *data;
829 	__u8 iir;
830 
831 	switch (status) {
832 	case 0:
833 		/* success */
834 		break;
835 	case -ECONNRESET:
836 	case -ENOENT:
837 	case -ESHUTDOWN:
838 	case -ENODEV:
839 		/* this urb is terminated, clean up */
840 		dev_dbg(dev, "%s - urb shutting down with status: %d\n", __func__, status);
841 		return;
842 	default:
843 		dev_dbg(dev, "%s - nonzero urb status received: %d\n", __func__, status);
844 		goto exit;
845 	}
846 
847 	length = urb->actual_length;
848 	data = urb->transfer_buffer;
849 
850 	/* Structure of data from 7715 device:
851 	 * Byte 1: IIR serial Port
852 	 * Byte 2: unused
853 	 * Byte 2: DSR parallel port
854 	 * Byte 4: FIFO status for both */
855 
856 	if (unlikely(length != 4)) {
857 		dev_dbg(dev, "Wrong data !!!\n");
858 		return;
859 	}
860 
861 	iir = data[0];
862 	if (!(iir & 0x01)) {	/* serial port interrupt pending */
863 		switch (iir & 0x0f) {
864 		case SERIAL_IIR_RLS:
865 			dev_dbg(dev, "Serial Port: Receiver status error or address bit detected in 9-bit mode\n\n");
866 			break;
867 		case SERIAL_IIR_CTI:
868 			dev_dbg(dev, "Serial Port: Receiver time out\n");
869 			break;
870 		case SERIAL_IIR_MS:
871 			/* dev_dbg(dev, "Serial Port: Modem status change\n"); */
872 			break;
873 		}
874 	}
875 
876 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
877 	{       /* update local copy of DSR reg */
878 		struct usb_serial_port *port = urb->context;
879 		struct mos7715_parport *mos_parport = port->serial->private;
880 		if (unlikely(mos_parport == NULL))
881 			return;
882 		atomic_set(&mos_parport->shadowDSR, data[2]);
883 	}
884 #endif
885 
886 exit:
887 	result = usb_submit_urb(urb, GFP_ATOMIC);
888 	if (result)
889 		dev_err(dev, "%s - Error %d submitting control urb\n", __func__, result);
890 }
891 
892 /*
893  * mos7720_bulk_in_callback
894  *	this is the callback function for when we have received data on the
895  *	bulk in endpoint.
896  */
897 static void mos7720_bulk_in_callback(struct urb *urb)
898 {
899 	int retval;
900 	unsigned char *data ;
901 	struct usb_serial_port *port;
902 	int status = urb->status;
903 
904 	if (status) {
905 		dev_dbg(&urb->dev->dev, "nonzero read bulk status received: %d\n", status);
906 		return;
907 	}
908 
909 	port = urb->context;
910 
911 	dev_dbg(&port->dev, "Entering...%s\n", __func__);
912 
913 	data = urb->transfer_buffer;
914 
915 	if (urb->actual_length) {
916 		tty_insert_flip_string(&port->port, data, urb->actual_length);
917 		tty_flip_buffer_push(&port->port);
918 	}
919 
920 	if (port->read_urb->status != -EINPROGRESS) {
921 		retval = usb_submit_urb(port->read_urb, GFP_ATOMIC);
922 		if (retval)
923 			dev_dbg(&port->dev, "usb_submit_urb(read bulk) failed, retval = %d\n", retval);
924 	}
925 }
926 
927 /*
928  * mos7720_bulk_out_data_callback
929  *	this is the callback function for when we have finished sending serial
930  *	data on the bulk out endpoint.
931  */
932 static void mos7720_bulk_out_data_callback(struct urb *urb)
933 {
934 	struct moschip_port *mos7720_port;
935 	struct tty_struct *tty;
936 	int status = urb->status;
937 
938 	if (status) {
939 		dev_dbg(&urb->dev->dev, "nonzero write bulk status received:%d\n", status);
940 		return;
941 	}
942 
943 	mos7720_port = urb->context;
944 	if (!mos7720_port) {
945 		dev_dbg(&urb->dev->dev, "NULL mos7720_port pointer\n");
946 		return ;
947 	}
948 
949 	tty = tty_port_tty_get(&mos7720_port->port->port);
950 
951 	if (tty && mos7720_port->open)
952 		tty_wakeup(tty);
953 	tty_kref_put(tty);
954 }
955 
956 /*
957  * mos77xx_probe
958  *	this function installs the appropriate read interrupt endpoint callback
959  *	depending on whether the device is a 7720 or 7715, thus avoiding costly
960  *	run-time checks in the high-frequency callback routine itself.
961  */
962 static int mos77xx_probe(struct usb_serial *serial,
963 			 const struct usb_device_id *id)
964 {
965 	if (id->idProduct == MOSCHIP_DEVICE_ID_7715)
966 		moschip7720_2port_driver.read_int_callback =
967 			mos7715_interrupt_callback;
968 	else
969 		moschip7720_2port_driver.read_int_callback =
970 			mos7720_interrupt_callback;
971 
972 	return 0;
973 }
974 
975 static int mos77xx_calc_num_ports(struct usb_serial *serial)
976 {
977 	u16 product = le16_to_cpu(serial->dev->descriptor.idProduct);
978 	if (product == MOSCHIP_DEVICE_ID_7715)
979 		return 1;
980 
981 	return 2;
982 }
983 
984 static int mos7720_open(struct tty_struct *tty, struct usb_serial_port *port)
985 {
986 	struct usb_serial *serial;
987 	struct urb *urb;
988 	struct moschip_port *mos7720_port;
989 	int response;
990 	int port_number;
991 	__u8 data;
992 	int allocated_urbs = 0;
993 	int j;
994 
995 	serial = port->serial;
996 
997 	mos7720_port = usb_get_serial_port_data(port);
998 	if (mos7720_port == NULL)
999 		return -ENODEV;
1000 
1001 	usb_clear_halt(serial->dev, port->write_urb->pipe);
1002 	usb_clear_halt(serial->dev, port->read_urb->pipe);
1003 
1004 	/* Initialising the write urb pool */
1005 	for (j = 0; j < NUM_URBS; ++j) {
1006 		urb = usb_alloc_urb(0, GFP_KERNEL);
1007 		mos7720_port->write_urb_pool[j] = urb;
1008 
1009 		if (urb == NULL) {
1010 			dev_err(&port->dev, "No more urbs???\n");
1011 			continue;
1012 		}
1013 
1014 		urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE,
1015 					       GFP_KERNEL);
1016 		if (!urb->transfer_buffer) {
1017 			dev_err(&port->dev,
1018 				"%s-out of memory for urb buffers.\n",
1019 				__func__);
1020 			usb_free_urb(mos7720_port->write_urb_pool[j]);
1021 			mos7720_port->write_urb_pool[j] = NULL;
1022 			continue;
1023 		}
1024 		allocated_urbs++;
1025 	}
1026 
1027 	if (!allocated_urbs)
1028 		return -ENOMEM;
1029 
1030 	 /* Initialize MCS7720 -- Write Init values to corresponding Registers
1031 	  *
1032 	  * Register Index
1033 	  * 0 : THR/RHR
1034 	  * 1 : IER
1035 	  * 2 : FCR
1036 	  * 3 : LCR
1037 	  * 4 : MCR
1038 	  * 5 : LSR
1039 	  * 6 : MSR
1040 	  * 7 : SPR
1041 	  *
1042 	  * 0x08 : SP1/2 Control Reg
1043 	  */
1044 	port_number = port->number - port->serial->minor;
1045 	read_mos_reg(serial, port_number, LSR, &data);
1046 
1047 	dev_dbg(&port->dev, "SS::%p LSR:%x\n", mos7720_port, data);
1048 
1049 	write_mos_reg(serial, dummy, SP1_REG, 0x02);
1050 	write_mos_reg(serial, dummy, SP2_REG, 0x02);
1051 
1052 	write_mos_reg(serial, port_number, IER, 0x00);
1053 	write_mos_reg(serial, port_number, FCR, 0x00);
1054 
1055 	write_mos_reg(serial, port_number, FCR, 0xcf);
1056 	mos7720_port->shadowLCR = 0x03;
1057 	write_mos_reg(serial, port_number, LCR, mos7720_port->shadowLCR);
1058 	mos7720_port->shadowMCR = 0x0b;
1059 	write_mos_reg(serial, port_number, MCR, mos7720_port->shadowMCR);
1060 
1061 	write_mos_reg(serial, port_number, SP_CONTROL_REG, 0x00);
1062 	read_mos_reg(serial, dummy, SP_CONTROL_REG, &data);
1063 	data = data | (port->number - port->serial->minor + 1);
1064 	write_mos_reg(serial, dummy, SP_CONTROL_REG, data);
1065 	mos7720_port->shadowLCR = 0x83;
1066 	write_mos_reg(serial, port_number, LCR, mos7720_port->shadowLCR);
1067 	write_mos_reg(serial, port_number, THR, 0x0c);
1068 	write_mos_reg(serial, port_number, IER, 0x00);
1069 	mos7720_port->shadowLCR = 0x03;
1070 	write_mos_reg(serial, port_number, LCR, mos7720_port->shadowLCR);
1071 	write_mos_reg(serial, port_number, IER, 0x0c);
1072 
1073 	response = usb_submit_urb(port->read_urb, GFP_KERNEL);
1074 	if (response)
1075 		dev_err(&port->dev, "%s - Error %d submitting read urb\n",
1076 							__func__, response);
1077 
1078 	/* initialize our icount structure */
1079 	memset(&(mos7720_port->icount), 0x00, sizeof(mos7720_port->icount));
1080 
1081 	/* initialize our port settings */
1082 	mos7720_port->shadowMCR = UART_MCR_OUT2; /* Must set to enable ints! */
1083 
1084 	/* send a open port command */
1085 	mos7720_port->open = 1;
1086 
1087 	return 0;
1088 }
1089 
1090 /*
1091  * mos7720_chars_in_buffer
1092  *	this function is called by the tty driver when it wants to know how many
1093  *	bytes of data we currently have outstanding in the port (data that has
1094  *	been written, but hasn't made it out the port yet)
1095  *	If successful, we return the number of bytes left to be written in the
1096  *	system,
1097  *	Otherwise we return a negative error number.
1098  */
1099 static int mos7720_chars_in_buffer(struct tty_struct *tty)
1100 {
1101 	struct usb_serial_port *port = tty->driver_data;
1102 	int i;
1103 	int chars = 0;
1104 	struct moschip_port *mos7720_port;
1105 
1106 	mos7720_port = usb_get_serial_port_data(port);
1107 	if (mos7720_port == NULL)
1108 		return 0;
1109 
1110 	for (i = 0; i < NUM_URBS; ++i) {
1111 		if (mos7720_port->write_urb_pool[i] &&
1112 		    mos7720_port->write_urb_pool[i]->status == -EINPROGRESS)
1113 			chars += URB_TRANSFER_BUFFER_SIZE;
1114 	}
1115 	dev_dbg(&port->dev, "%s - returns %d\n", __func__, chars);
1116 	return chars;
1117 }
1118 
1119 static void mos7720_close(struct usb_serial_port *port)
1120 {
1121 	struct usb_serial *serial;
1122 	struct moschip_port *mos7720_port;
1123 	int j;
1124 
1125 	serial = port->serial;
1126 
1127 	mos7720_port = usb_get_serial_port_data(port);
1128 	if (mos7720_port == NULL)
1129 		return;
1130 
1131 	for (j = 0; j < NUM_URBS; ++j)
1132 		usb_kill_urb(mos7720_port->write_urb_pool[j]);
1133 
1134 	/* Freeing Write URBs */
1135 	for (j = 0; j < NUM_URBS; ++j) {
1136 		if (mos7720_port->write_urb_pool[j]) {
1137 			kfree(mos7720_port->write_urb_pool[j]->transfer_buffer);
1138 			usb_free_urb(mos7720_port->write_urb_pool[j]);
1139 		}
1140 	}
1141 
1142 	/* While closing port, shutdown all bulk read, write  *
1143 	 * and interrupt read if they exists, otherwise nop   */
1144 	usb_kill_urb(port->write_urb);
1145 	usb_kill_urb(port->read_urb);
1146 
1147 	mutex_lock(&serial->disc_mutex);
1148 	/* these commands must not be issued if the device has
1149 	 * been disconnected */
1150 	if (!serial->disconnected) {
1151 		write_mos_reg(serial, port->number - port->serial->minor,
1152 			      MCR, 0x00);
1153 		write_mos_reg(serial, port->number - port->serial->minor,
1154 			      IER, 0x00);
1155 	}
1156 	mutex_unlock(&serial->disc_mutex);
1157 	mos7720_port->open = 0;
1158 }
1159 
1160 static void mos7720_break(struct tty_struct *tty, int break_state)
1161 {
1162 	struct usb_serial_port *port = tty->driver_data;
1163 	unsigned char data;
1164 	struct usb_serial *serial;
1165 	struct moschip_port *mos7720_port;
1166 
1167 	serial = port->serial;
1168 
1169 	mos7720_port = usb_get_serial_port_data(port);
1170 	if (mos7720_port == NULL)
1171 		return;
1172 
1173 	if (break_state == -1)
1174 		data = mos7720_port->shadowLCR | UART_LCR_SBC;
1175 	else
1176 		data = mos7720_port->shadowLCR & ~UART_LCR_SBC;
1177 
1178 	mos7720_port->shadowLCR  = data;
1179 	write_mos_reg(serial, port->number - port->serial->minor,
1180 		      LCR, mos7720_port->shadowLCR);
1181 }
1182 
1183 /*
1184  * mos7720_write_room
1185  *	this function is called by the tty driver when it wants to know how many
1186  *	bytes of data we can accept for a specific port.
1187  *	If successful, we return the amount of room that we have for this port
1188  *	Otherwise we return a negative error number.
1189  */
1190 static int mos7720_write_room(struct tty_struct *tty)
1191 {
1192 	struct usb_serial_port *port = tty->driver_data;
1193 	struct moschip_port *mos7720_port;
1194 	int room = 0;
1195 	int i;
1196 
1197 	mos7720_port = usb_get_serial_port_data(port);
1198 	if (mos7720_port == NULL)
1199 		return -ENODEV;
1200 
1201 	/* FIXME: Locking */
1202 	for (i = 0; i < NUM_URBS; ++i) {
1203 		if (mos7720_port->write_urb_pool[i] &&
1204 		    mos7720_port->write_urb_pool[i]->status != -EINPROGRESS)
1205 			room += URB_TRANSFER_BUFFER_SIZE;
1206 	}
1207 
1208 	dev_dbg(&port->dev, "%s - returns %d\n", __func__, room);
1209 	return room;
1210 }
1211 
1212 static int mos7720_write(struct tty_struct *tty, struct usb_serial_port *port,
1213 				 const unsigned char *data, int count)
1214 {
1215 	int status;
1216 	int i;
1217 	int bytes_sent = 0;
1218 	int transfer_size;
1219 
1220 	struct moschip_port *mos7720_port;
1221 	struct usb_serial *serial;
1222 	struct urb    *urb;
1223 	const unsigned char *current_position = data;
1224 
1225 	serial = port->serial;
1226 
1227 	mos7720_port = usb_get_serial_port_data(port);
1228 	if (mos7720_port == NULL)
1229 		return -ENODEV;
1230 
1231 	/* try to find a free urb in the list */
1232 	urb = NULL;
1233 
1234 	for (i = 0; i < NUM_URBS; ++i) {
1235 		if (mos7720_port->write_urb_pool[i] &&
1236 		    mos7720_port->write_urb_pool[i]->status != -EINPROGRESS) {
1237 			urb = mos7720_port->write_urb_pool[i];
1238 			dev_dbg(&port->dev, "URB:%d\n", i);
1239 			break;
1240 		}
1241 	}
1242 
1243 	if (urb == NULL) {
1244 		dev_dbg(&port->dev, "%s - no more free urbs\n", __func__);
1245 		goto exit;
1246 	}
1247 
1248 	if (urb->transfer_buffer == NULL) {
1249 		urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE,
1250 					       GFP_KERNEL);
1251 		if (urb->transfer_buffer == NULL) {
1252 			dev_err_console(port, "%s no more kernel memory...\n",
1253 				__func__);
1254 			goto exit;
1255 		}
1256 	}
1257 	transfer_size = min(count, URB_TRANSFER_BUFFER_SIZE);
1258 
1259 	memcpy(urb->transfer_buffer, current_position, transfer_size);
1260 	usb_serial_debug_data(&port->dev, __func__, transfer_size,
1261 			      urb->transfer_buffer);
1262 
1263 	/* fill urb with data and submit  */
1264 	usb_fill_bulk_urb(urb, serial->dev,
1265 			  usb_sndbulkpipe(serial->dev,
1266 					port->bulk_out_endpointAddress),
1267 			  urb->transfer_buffer, transfer_size,
1268 			  mos7720_bulk_out_data_callback, mos7720_port);
1269 
1270 	/* send it down the pipe */
1271 	status = usb_submit_urb(urb, GFP_ATOMIC);
1272 	if (status) {
1273 		dev_err_console(port, "%s - usb_submit_urb(write bulk) failed "
1274 			"with status = %d\n", __func__, status);
1275 		bytes_sent = status;
1276 		goto exit;
1277 	}
1278 	bytes_sent = transfer_size;
1279 
1280 exit:
1281 	return bytes_sent;
1282 }
1283 
1284 static void mos7720_throttle(struct tty_struct *tty)
1285 {
1286 	struct usb_serial_port *port = tty->driver_data;
1287 	struct moschip_port *mos7720_port;
1288 	int status;
1289 
1290 	mos7720_port = usb_get_serial_port_data(port);
1291 
1292 	if (mos7720_port == NULL)
1293 		return;
1294 
1295 	if (!mos7720_port->open) {
1296 		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
1297 		return;
1298 	}
1299 
1300 	/* if we are implementing XON/XOFF, send the stop character */
1301 	if (I_IXOFF(tty)) {
1302 		unsigned char stop_char = STOP_CHAR(tty);
1303 		status = mos7720_write(tty, port, &stop_char, 1);
1304 		if (status <= 0)
1305 			return;
1306 	}
1307 
1308 	/* if we are implementing RTS/CTS, toggle that line */
1309 	if (tty->termios.c_cflag & CRTSCTS) {
1310 		mos7720_port->shadowMCR &= ~UART_MCR_RTS;
1311 		write_mos_reg(port->serial, port->number - port->serial->minor,
1312 			      MCR, mos7720_port->shadowMCR);
1313 		if (status != 0)
1314 			return;
1315 	}
1316 }
1317 
1318 static void mos7720_unthrottle(struct tty_struct *tty)
1319 {
1320 	struct usb_serial_port *port = tty->driver_data;
1321 	struct moschip_port *mos7720_port = usb_get_serial_port_data(port);
1322 	int status;
1323 
1324 	if (mos7720_port == NULL)
1325 		return;
1326 
1327 	if (!mos7720_port->open) {
1328 		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
1329 		return;
1330 	}
1331 
1332 	/* if we are implementing XON/XOFF, send the start character */
1333 	if (I_IXOFF(tty)) {
1334 		unsigned char start_char = START_CHAR(tty);
1335 		status = mos7720_write(tty, port, &start_char, 1);
1336 		if (status <= 0)
1337 			return;
1338 	}
1339 
1340 	/* if we are implementing RTS/CTS, toggle that line */
1341 	if (tty->termios.c_cflag & CRTSCTS) {
1342 		mos7720_port->shadowMCR |= UART_MCR_RTS;
1343 		write_mos_reg(port->serial, port->number - port->serial->minor,
1344 			      MCR, mos7720_port->shadowMCR);
1345 		if (status != 0)
1346 			return;
1347 	}
1348 }
1349 
1350 /* FIXME: this function does not work */
1351 static int set_higher_rates(struct moschip_port *mos7720_port,
1352 			    unsigned int baud)
1353 {
1354 	struct usb_serial_port *port;
1355 	struct usb_serial *serial;
1356 	int port_number;
1357 	enum mos_regs sp_reg;
1358 	if (mos7720_port == NULL)
1359 		return -EINVAL;
1360 
1361 	port = mos7720_port->port;
1362 	serial = port->serial;
1363 
1364 	 /***********************************************
1365 	 *      Init Sequence for higher rates
1366 	 ***********************************************/
1367 	dev_dbg(&port->dev, "Sending Setting Commands ..........\n");
1368 	port_number = port->number - port->serial->minor;
1369 
1370 	write_mos_reg(serial, port_number, IER, 0x00);
1371 	write_mos_reg(serial, port_number, FCR, 0x00);
1372 	write_mos_reg(serial, port_number, FCR, 0xcf);
1373 	mos7720_port->shadowMCR = 0x0b;
1374 	write_mos_reg(serial, port_number, MCR, mos7720_port->shadowMCR);
1375 	write_mos_reg(serial, dummy, SP_CONTROL_REG, 0x00);
1376 
1377 	/***********************************************
1378 	 *              Set for higher rates           *
1379 	 ***********************************************/
1380 	/* writing baud rate verbatum into uart clock field clearly not right */
1381 	if (port_number == 0)
1382 		sp_reg = SP1_REG;
1383 	else
1384 		sp_reg = SP2_REG;
1385 	write_mos_reg(serial, dummy, sp_reg, baud * 0x10);
1386 	write_mos_reg(serial, dummy, SP_CONTROL_REG, 0x03);
1387 	mos7720_port->shadowMCR = 0x2b;
1388 	write_mos_reg(serial, port_number, MCR, mos7720_port->shadowMCR);
1389 
1390 	/***********************************************
1391 	 *              Set DLL/DLM
1392 	 ***********************************************/
1393 	mos7720_port->shadowLCR = mos7720_port->shadowLCR | UART_LCR_DLAB;
1394 	write_mos_reg(serial, port_number, LCR, mos7720_port->shadowLCR);
1395 	write_mos_reg(serial, port_number, DLL, 0x01);
1396 	write_mos_reg(serial, port_number, DLM, 0x00);
1397 	mos7720_port->shadowLCR = mos7720_port->shadowLCR & ~UART_LCR_DLAB;
1398 	write_mos_reg(serial, port_number, LCR, mos7720_port->shadowLCR);
1399 
1400 	return 0;
1401 }
1402 
1403 /* baud rate information */
1404 struct divisor_table_entry {
1405 	__u32  baudrate;
1406 	__u16  divisor;
1407 };
1408 
1409 /* Define table of divisors for moschip 7720 hardware	   *
1410  * These assume a 3.6864MHz crystal, the standard /16, and *
1411  * MCR.7 = 0.						   */
1412 static struct divisor_table_entry divisor_table[] = {
1413 	{   50,		2304},
1414 	{   110,	1047},	/* 2094.545455 => 230450   => .0217 % over */
1415 	{   134,	857},	/* 1713.011152 => 230398.5 => .00065% under */
1416 	{   150,	768},
1417 	{   300,	384},
1418 	{   600,	192},
1419 	{   1200,	96},
1420 	{   1800,	64},
1421 	{   2400,	48},
1422 	{   4800,	24},
1423 	{   7200,	16},
1424 	{   9600,	12},
1425 	{   19200,	6},
1426 	{   38400,	3},
1427 	{   57600,	2},
1428 	{   115200,	1},
1429 };
1430 
1431 /*****************************************************************************
1432  * calc_baud_rate_divisor
1433  *	this function calculates the proper baud rate divisor for the specified
1434  *	baud rate.
1435  *****************************************************************************/
1436 static int calc_baud_rate_divisor(struct usb_serial_port *port, int baudrate, int *divisor)
1437 {
1438 	int i;
1439 	__u16 custom;
1440 	__u16 round1;
1441 	__u16 round;
1442 
1443 
1444 	dev_dbg(&port->dev, "%s - %d\n", __func__, baudrate);
1445 
1446 	for (i = 0; i < ARRAY_SIZE(divisor_table); i++) {
1447 		if (divisor_table[i].baudrate == baudrate) {
1448 			*divisor = divisor_table[i].divisor;
1449 			return 0;
1450 		}
1451 	}
1452 
1453 	/* After trying for all the standard baud rates    *
1454 	 * Try calculating the divisor for this baud rate  */
1455 	if (baudrate > 75 &&  baudrate < 230400) {
1456 		/* get the divisor */
1457 		custom = (__u16)(230400L  / baudrate);
1458 
1459 		/* Check for round off */
1460 		round1 = (__u16)(2304000L / baudrate);
1461 		round = (__u16)(round1 - (custom * 10));
1462 		if (round > 4)
1463 			custom++;
1464 		*divisor = custom;
1465 
1466 		dev_dbg(&port->dev, "Baud %d = %d\n", baudrate, custom);
1467 		return 0;
1468 	}
1469 
1470 	dev_dbg(&port->dev, "Baud calculation Failed...\n");
1471 	return -EINVAL;
1472 }
1473 
1474 /*
1475  * send_cmd_write_baud_rate
1476  *	this function sends the proper command to change the baud rate of the
1477  *	specified port.
1478  */
1479 static int send_cmd_write_baud_rate(struct moschip_port *mos7720_port,
1480 				    int baudrate)
1481 {
1482 	struct usb_serial_port *port;
1483 	struct usb_serial *serial;
1484 	int divisor;
1485 	int status;
1486 	unsigned char number;
1487 
1488 	if (mos7720_port == NULL)
1489 		return -1;
1490 
1491 	port = mos7720_port->port;
1492 	serial = port->serial;
1493 
1494 	number = port->number - port->serial->minor;
1495 	dev_dbg(&port->dev, "%s - baud = %d\n", __func__, baudrate);
1496 
1497 	/* Calculate the Divisor */
1498 	status = calc_baud_rate_divisor(port, baudrate, &divisor);
1499 	if (status) {
1500 		dev_err(&port->dev, "%s - bad baud rate\n", __func__);
1501 		return status;
1502 	}
1503 
1504 	/* Enable access to divisor latch */
1505 	mos7720_port->shadowLCR = mos7720_port->shadowLCR | UART_LCR_DLAB;
1506 	write_mos_reg(serial, number, LCR, mos7720_port->shadowLCR);
1507 
1508 	/* Write the divisor */
1509 	write_mos_reg(serial, number, DLL, (__u8)(divisor & 0xff));
1510 	write_mos_reg(serial, number, DLM, (__u8)((divisor & 0xff00) >> 8));
1511 
1512 	/* Disable access to divisor latch */
1513 	mos7720_port->shadowLCR = mos7720_port->shadowLCR & ~UART_LCR_DLAB;
1514 	write_mos_reg(serial, number, LCR, mos7720_port->shadowLCR);
1515 
1516 	return status;
1517 }
1518 
1519 /*
1520  * change_port_settings
1521  *	This routine is called to set the UART on the device to match
1522  *      the specified new settings.
1523  */
1524 static void change_port_settings(struct tty_struct *tty,
1525 				 struct moschip_port *mos7720_port,
1526 				 struct ktermios *old_termios)
1527 {
1528 	struct usb_serial_port *port;
1529 	struct usb_serial *serial;
1530 	int baud;
1531 	unsigned cflag;
1532 	unsigned iflag;
1533 	__u8 mask = 0xff;
1534 	__u8 lData;
1535 	__u8 lParity;
1536 	__u8 lStop;
1537 	int status;
1538 	int port_number;
1539 
1540 	if (mos7720_port == NULL)
1541 		return ;
1542 
1543 	port = mos7720_port->port;
1544 	serial = port->serial;
1545 	port_number = port->number - port->serial->minor;
1546 
1547 	if (!mos7720_port->open) {
1548 		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
1549 		return;
1550 	}
1551 
1552 	lData = UART_LCR_WLEN8;
1553 	lStop = 0x00;	/* 1 stop bit */
1554 	lParity = 0x00;	/* No parity */
1555 
1556 	cflag = tty->termios.c_cflag;
1557 	iflag = tty->termios.c_iflag;
1558 
1559 	/* Change the number of bits */
1560 	switch (cflag & CSIZE) {
1561 	case CS5:
1562 		lData = UART_LCR_WLEN5;
1563 		mask = 0x1f;
1564 		break;
1565 
1566 	case CS6:
1567 		lData = UART_LCR_WLEN6;
1568 		mask = 0x3f;
1569 		break;
1570 
1571 	case CS7:
1572 		lData = UART_LCR_WLEN7;
1573 		mask = 0x7f;
1574 		break;
1575 	default:
1576 	case CS8:
1577 		lData = UART_LCR_WLEN8;
1578 		break;
1579 	}
1580 
1581 	/* Change the Parity bit */
1582 	if (cflag & PARENB) {
1583 		if (cflag & PARODD) {
1584 			lParity = UART_LCR_PARITY;
1585 			dev_dbg(&port->dev, "%s - parity = odd\n", __func__);
1586 		} else {
1587 			lParity = (UART_LCR_EPAR | UART_LCR_PARITY);
1588 			dev_dbg(&port->dev, "%s - parity = even\n", __func__);
1589 		}
1590 
1591 	} else {
1592 		dev_dbg(&port->dev, "%s - parity = none\n", __func__);
1593 	}
1594 
1595 	if (cflag & CMSPAR)
1596 		lParity = lParity | 0x20;
1597 
1598 	/* Change the Stop bit */
1599 	if (cflag & CSTOPB) {
1600 		lStop = UART_LCR_STOP;
1601 		dev_dbg(&port->dev, "%s - stop bits = 2\n", __func__);
1602 	} else {
1603 		lStop = 0x00;
1604 		dev_dbg(&port->dev, "%s - stop bits = 1\n", __func__);
1605 	}
1606 
1607 #define LCR_BITS_MASK		0x03	/* Mask for bits/char field */
1608 #define LCR_STOP_MASK		0x04	/* Mask for stop bits field */
1609 #define LCR_PAR_MASK		0x38	/* Mask for parity field */
1610 
1611 	/* Update the LCR with the correct value */
1612 	mos7720_port->shadowLCR &=
1613 		~(LCR_BITS_MASK | LCR_STOP_MASK | LCR_PAR_MASK);
1614 	mos7720_port->shadowLCR |= (lData | lParity | lStop);
1615 
1616 
1617 	/* Disable Interrupts */
1618 	write_mos_reg(serial, port_number, IER, 0x00);
1619 	write_mos_reg(serial, port_number, FCR, 0x00);
1620 	write_mos_reg(serial, port_number, FCR, 0xcf);
1621 
1622 	/* Send the updated LCR value to the mos7720 */
1623 	write_mos_reg(serial, port_number, LCR, mos7720_port->shadowLCR);
1624 	mos7720_port->shadowMCR = 0x0b;
1625 	write_mos_reg(serial, port_number, MCR, mos7720_port->shadowMCR);
1626 
1627 	/* set up the MCR register and send it to the mos7720 */
1628 	mos7720_port->shadowMCR = UART_MCR_OUT2;
1629 	if (cflag & CBAUD)
1630 		mos7720_port->shadowMCR |= (UART_MCR_DTR | UART_MCR_RTS);
1631 
1632 	if (cflag & CRTSCTS) {
1633 		mos7720_port->shadowMCR |= (UART_MCR_XONANY);
1634 		/* To set hardware flow control to the specified *
1635 		 * serial port, in SP1/2_CONTROL_REG             */
1636 		if (port->number)
1637 			write_mos_reg(serial, dummy, SP_CONTROL_REG, 0x01);
1638 		else
1639 			write_mos_reg(serial, dummy, SP_CONTROL_REG, 0x02);
1640 
1641 	} else
1642 		mos7720_port->shadowMCR &= ~(UART_MCR_XONANY);
1643 
1644 	write_mos_reg(serial, port_number, MCR, mos7720_port->shadowMCR);
1645 
1646 	/* Determine divisor based on baud rate */
1647 	baud = tty_get_baud_rate(tty);
1648 	if (!baud) {
1649 		/* pick a default, any default... */
1650 		dev_dbg(&port->dev, "Picked default baud...\n");
1651 		baud = 9600;
1652 	}
1653 
1654 	if (baud >= 230400) {
1655 		set_higher_rates(mos7720_port, baud);
1656 		/* Enable Interrupts */
1657 		write_mos_reg(serial, port_number, IER, 0x0c);
1658 		return;
1659 	}
1660 
1661 	dev_dbg(&port->dev, "%s - baud rate = %d\n", __func__, baud);
1662 	status = send_cmd_write_baud_rate(mos7720_port, baud);
1663 	/* FIXME: needs to write actual resulting baud back not just
1664 	   blindly do so */
1665 	if (cflag & CBAUD)
1666 		tty_encode_baud_rate(tty, baud, baud);
1667 	/* Enable Interrupts */
1668 	write_mos_reg(serial, port_number, IER, 0x0c);
1669 
1670 	if (port->read_urb->status != -EINPROGRESS) {
1671 		status = usb_submit_urb(port->read_urb, GFP_ATOMIC);
1672 		if (status)
1673 			dev_dbg(&port->dev, "usb_submit_urb(read bulk) failed, status = %d\n", status);
1674 	}
1675 }
1676 
1677 /*
1678  * mos7720_set_termios
1679  *	this function is called by the tty driver when it wants to change the
1680  *	termios structure.
1681  */
1682 static void mos7720_set_termios(struct tty_struct *tty,
1683 		struct usb_serial_port *port, struct ktermios *old_termios)
1684 {
1685 	int status;
1686 	unsigned int cflag;
1687 	struct usb_serial *serial;
1688 	struct moschip_port *mos7720_port;
1689 
1690 	serial = port->serial;
1691 
1692 	mos7720_port = usb_get_serial_port_data(port);
1693 
1694 	if (mos7720_port == NULL)
1695 		return;
1696 
1697 	if (!mos7720_port->open) {
1698 		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
1699 		return;
1700 	}
1701 
1702 	dev_dbg(&port->dev, "setting termios - ASPIRE\n");
1703 
1704 	cflag = tty->termios.c_cflag;
1705 
1706 	dev_dbg(&port->dev, "%s - cflag %08x iflag %08x\n", __func__,
1707 		tty->termios.c_cflag, RELEVANT_IFLAG(tty->termios.c_iflag));
1708 
1709 	dev_dbg(&port->dev, "%s - old cflag %08x old iflag %08x\n", __func__,
1710 		old_termios->c_cflag, RELEVANT_IFLAG(old_termios->c_iflag));
1711 
1712 	/* change the port settings to the new ones specified */
1713 	change_port_settings(tty, mos7720_port, old_termios);
1714 
1715 	if (port->read_urb->status != -EINPROGRESS) {
1716 		status = usb_submit_urb(port->read_urb, GFP_ATOMIC);
1717 		if (status)
1718 			dev_dbg(&port->dev, "usb_submit_urb(read bulk) failed, status = %d\n", status);
1719 	}
1720 }
1721 
1722 /*
1723  * get_lsr_info - get line status register info
1724  *
1725  * Purpose: Let user call ioctl() to get info when the UART physically
1726  * 	    is emptied.  On bus types like RS485, the transmitter must
1727  * 	    release the bus after transmitting. This must be done when
1728  * 	    the transmit shift register is empty, not be done when the
1729  * 	    transmit holding register is empty.  This functionality
1730  * 	    allows an RS485 driver to be written in user space.
1731  */
1732 static int get_lsr_info(struct tty_struct *tty,
1733 		struct moschip_port *mos7720_port, unsigned int __user *value)
1734 {
1735 	struct usb_serial_port *port = tty->driver_data;
1736 	unsigned int result = 0;
1737 	unsigned char data = 0;
1738 	int port_number = port->number - port->serial->minor;
1739 	int count;
1740 
1741 	count = mos7720_chars_in_buffer(tty);
1742 	if (count == 0) {
1743 		read_mos_reg(port->serial, port_number, LSR, &data);
1744 		if ((data & (UART_LSR_TEMT | UART_LSR_THRE))
1745 					== (UART_LSR_TEMT | UART_LSR_THRE)) {
1746 			dev_dbg(&port->dev, "%s -- Empty\n", __func__);
1747 			result = TIOCSER_TEMT;
1748 		}
1749 	}
1750 	if (copy_to_user(value, &result, sizeof(int)))
1751 		return -EFAULT;
1752 	return 0;
1753 }
1754 
1755 static int mos7720_tiocmget(struct tty_struct *tty)
1756 {
1757 	struct usb_serial_port *port = tty->driver_data;
1758 	struct moschip_port *mos7720_port = usb_get_serial_port_data(port);
1759 	unsigned int result = 0;
1760 	unsigned int mcr ;
1761 	unsigned int msr ;
1762 
1763 	mcr = mos7720_port->shadowMCR;
1764 	msr = mos7720_port->shadowMSR;
1765 
1766 	result = ((mcr & UART_MCR_DTR)  ? TIOCM_DTR : 0)   /* 0x002 */
1767 	  | ((mcr & UART_MCR_RTS)   ? TIOCM_RTS : 0)   /* 0x004 */
1768 	  | ((msr & UART_MSR_CTS)   ? TIOCM_CTS : 0)   /* 0x020 */
1769 	  | ((msr & UART_MSR_DCD)   ? TIOCM_CAR : 0)   /* 0x040 */
1770 	  | ((msr & UART_MSR_RI)    ? TIOCM_RI :  0)   /* 0x080 */
1771 	  | ((msr & UART_MSR_DSR)   ? TIOCM_DSR : 0);  /* 0x100 */
1772 
1773 	return result;
1774 }
1775 
1776 static int mos7720_tiocmset(struct tty_struct *tty,
1777 			    unsigned int set, unsigned int clear)
1778 {
1779 	struct usb_serial_port *port = tty->driver_data;
1780 	struct moschip_port *mos7720_port = usb_get_serial_port_data(port);
1781 	unsigned int mcr ;
1782 
1783 	mcr = mos7720_port->shadowMCR;
1784 
1785 	if (set & TIOCM_RTS)
1786 		mcr |= UART_MCR_RTS;
1787 	if (set & TIOCM_DTR)
1788 		mcr |= UART_MCR_DTR;
1789 	if (set & TIOCM_LOOP)
1790 		mcr |= UART_MCR_LOOP;
1791 
1792 	if (clear & TIOCM_RTS)
1793 		mcr &= ~UART_MCR_RTS;
1794 	if (clear & TIOCM_DTR)
1795 		mcr &= ~UART_MCR_DTR;
1796 	if (clear & TIOCM_LOOP)
1797 		mcr &= ~UART_MCR_LOOP;
1798 
1799 	mos7720_port->shadowMCR = mcr;
1800 	write_mos_reg(port->serial, port->number - port->serial->minor,
1801 		      MCR, mos7720_port->shadowMCR);
1802 
1803 	return 0;
1804 }
1805 
1806 static int mos7720_get_icount(struct tty_struct *tty,
1807 				struct serial_icounter_struct *icount)
1808 {
1809 	struct usb_serial_port *port = tty->driver_data;
1810 	struct moschip_port *mos7720_port;
1811 	struct async_icount cnow;
1812 
1813 	mos7720_port = usb_get_serial_port_data(port);
1814 	cnow = mos7720_port->icount;
1815 
1816 	icount->cts = cnow.cts;
1817 	icount->dsr = cnow.dsr;
1818 	icount->rng = cnow.rng;
1819 	icount->dcd = cnow.dcd;
1820 	icount->rx = cnow.rx;
1821 	icount->tx = cnow.tx;
1822 	icount->frame = cnow.frame;
1823 	icount->overrun = cnow.overrun;
1824 	icount->parity = cnow.parity;
1825 	icount->brk = cnow.brk;
1826 	icount->buf_overrun = cnow.buf_overrun;
1827 
1828 	dev_dbg(&port->dev, "%s TIOCGICOUNT RX=%d, TX=%d\n", __func__,
1829 		icount->rx, icount->tx);
1830 	return 0;
1831 }
1832 
1833 static int set_modem_info(struct moschip_port *mos7720_port, unsigned int cmd,
1834 			  unsigned int __user *value)
1835 {
1836 	unsigned int mcr;
1837 	unsigned int arg;
1838 
1839 	struct usb_serial_port *port;
1840 
1841 	if (mos7720_port == NULL)
1842 		return -1;
1843 
1844 	port = (struct usb_serial_port *)mos7720_port->port;
1845 	mcr = mos7720_port->shadowMCR;
1846 
1847 	if (copy_from_user(&arg, value, sizeof(int)))
1848 		return -EFAULT;
1849 
1850 	switch (cmd) {
1851 	case TIOCMBIS:
1852 		if (arg & TIOCM_RTS)
1853 			mcr |= UART_MCR_RTS;
1854 		if (arg & TIOCM_DTR)
1855 			mcr |= UART_MCR_RTS;
1856 		if (arg & TIOCM_LOOP)
1857 			mcr |= UART_MCR_LOOP;
1858 		break;
1859 
1860 	case TIOCMBIC:
1861 		if (arg & TIOCM_RTS)
1862 			mcr &= ~UART_MCR_RTS;
1863 		if (arg & TIOCM_DTR)
1864 			mcr &= ~UART_MCR_RTS;
1865 		if (arg & TIOCM_LOOP)
1866 			mcr &= ~UART_MCR_LOOP;
1867 		break;
1868 
1869 	}
1870 
1871 	mos7720_port->shadowMCR = mcr;
1872 	write_mos_reg(port->serial, port->number - port->serial->minor,
1873 		      MCR, mos7720_port->shadowMCR);
1874 
1875 	return 0;
1876 }
1877 
1878 static int get_serial_info(struct moschip_port *mos7720_port,
1879 			   struct serial_struct __user *retinfo)
1880 {
1881 	struct serial_struct tmp;
1882 
1883 	if (!retinfo)
1884 		return -EFAULT;
1885 
1886 	memset(&tmp, 0, sizeof(tmp));
1887 
1888 	tmp.type		= PORT_16550A;
1889 	tmp.line		= mos7720_port->port->serial->minor;
1890 	tmp.port		= mos7720_port->port->number;
1891 	tmp.irq			= 0;
1892 	tmp.flags		= ASYNC_SKIP_TEST | ASYNC_AUTO_IRQ;
1893 	tmp.xmit_fifo_size	= NUM_URBS * URB_TRANSFER_BUFFER_SIZE;
1894 	tmp.baud_base		= 9600;
1895 	tmp.close_delay		= 5*HZ;
1896 	tmp.closing_wait	= 30*HZ;
1897 
1898 	if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
1899 		return -EFAULT;
1900 	return 0;
1901 }
1902 
1903 static int mos7720_ioctl(struct tty_struct *tty,
1904 			 unsigned int cmd, unsigned long arg)
1905 {
1906 	struct usb_serial_port *port = tty->driver_data;
1907 	struct moschip_port *mos7720_port;
1908 	struct async_icount cnow;
1909 	struct async_icount cprev;
1910 
1911 	mos7720_port = usb_get_serial_port_data(port);
1912 	if (mos7720_port == NULL)
1913 		return -ENODEV;
1914 
1915 	dev_dbg(&port->dev, "%s - cmd = 0x%x", __func__, cmd);
1916 
1917 	switch (cmd) {
1918 	case TIOCSERGETLSR:
1919 		dev_dbg(&port->dev, "%s TIOCSERGETLSR\n", __func__);
1920 		return get_lsr_info(tty, mos7720_port,
1921 					(unsigned int __user *)arg);
1922 
1923 	/* FIXME: These should be using the mode methods */
1924 	case TIOCMBIS:
1925 	case TIOCMBIC:
1926 		dev_dbg(&port->dev, "%s TIOCMSET/TIOCMBIC/TIOCMSET\n", __func__);
1927 		return set_modem_info(mos7720_port, cmd,
1928 				      (unsigned int __user *)arg);
1929 
1930 	case TIOCGSERIAL:
1931 		dev_dbg(&port->dev, "%s TIOCGSERIAL\n", __func__);
1932 		return get_serial_info(mos7720_port,
1933 				       (struct serial_struct __user *)arg);
1934 
1935 	case TIOCMIWAIT:
1936 		dev_dbg(&port->dev, "%s TIOCMIWAIT\n", __func__);
1937 		cprev = mos7720_port->icount;
1938 		while (1) {
1939 			if (signal_pending(current))
1940 				return -ERESTARTSYS;
1941 			cnow = mos7720_port->icount;
1942 			if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
1943 			    cnow.dcd == cprev.dcd && cnow.cts == cprev.cts)
1944 				return -EIO; /* no change => error */
1945 			if (((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) ||
1946 			    ((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) ||
1947 			    ((arg & TIOCM_CD)  && (cnow.dcd != cprev.dcd)) ||
1948 			    ((arg & TIOCM_CTS) && (cnow.cts != cprev.cts))) {
1949 				return 0;
1950 			}
1951 			cprev = cnow;
1952 		}
1953 		/* NOTREACHED */
1954 		break;
1955 	}
1956 
1957 	return -ENOIOCTLCMD;
1958 }
1959 
1960 static int mos7720_startup(struct usb_serial *serial)
1961 {
1962 	struct usb_device *dev;
1963 	char data;
1964 	u16 product;
1965 	int ret_val;
1966 
1967 	product = le16_to_cpu(serial->dev->descriptor.idProduct);
1968 	dev = serial->dev;
1969 
1970 	/*
1971 	 * The 7715 uses the first bulk in/out endpoint pair for the parallel
1972 	 * port, and the second for the serial port.  Because the usbserial core
1973 	 * assumes both pairs are serial ports, we must engage in a bit of
1974 	 * subterfuge and swap the pointers for ports 0 and 1 in order to make
1975 	 * port 0 point to the serial port.  However, both moschip devices use a
1976 	 * single interrupt-in endpoint for both ports (as mentioned a little
1977 	 * further down), and this endpoint was assigned to port 0.  So after
1978 	 * the swap, we must copy the interrupt endpoint elements from port 1
1979 	 * (as newly assigned) to port 0, and null out port 1 pointers.
1980 	 */
1981 	if (product == MOSCHIP_DEVICE_ID_7715) {
1982 		struct usb_serial_port *tmp = serial->port[0];
1983 		serial->port[0] = serial->port[1];
1984 		serial->port[1] = tmp;
1985 		serial->port[0]->interrupt_in_urb = tmp->interrupt_in_urb;
1986 		serial->port[0]->interrupt_in_buffer = tmp->interrupt_in_buffer;
1987 		serial->port[0]->interrupt_in_endpointAddress =
1988 			tmp->interrupt_in_endpointAddress;
1989 		serial->port[1]->interrupt_in_urb = NULL;
1990 		serial->port[1]->interrupt_in_buffer = NULL;
1991 	}
1992 
1993 	/* setting configuration feature to one */
1994 	usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
1995 			(__u8)0x03, 0x00, 0x01, 0x00, NULL, 0x00, 5*HZ);
1996 
1997 	/* start the interrupt urb */
1998 	ret_val = usb_submit_urb(serial->port[0]->interrupt_in_urb, GFP_KERNEL);
1999 	if (ret_val)
2000 		dev_err(&dev->dev,
2001 			"%s - Error %d submitting control urb\n",
2002 			__func__, ret_val);
2003 
2004 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
2005 	if (product == MOSCHIP_DEVICE_ID_7715) {
2006 		ret_val = mos7715_parport_init(serial);
2007 		if (ret_val < 0)
2008 			return ret_val;
2009 	}
2010 #endif
2011 	/* LSR For Port 1 */
2012 	read_mos_reg(serial, 0, LSR, &data);
2013 	dev_dbg(&dev->dev, "LSR:%x\n", data);
2014 
2015 	return 0;
2016 }
2017 
2018 static void mos7720_release(struct usb_serial *serial)
2019 {
2020 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
2021 	/* close the parallel port */
2022 
2023 	if (le16_to_cpu(serial->dev->descriptor.idProduct)
2024 	    == MOSCHIP_DEVICE_ID_7715) {
2025 		struct urbtracker *urbtrack;
2026 		unsigned long flags;
2027 		struct mos7715_parport *mos_parport =
2028 			usb_get_serial_data(serial);
2029 
2030 		/* prevent NULL ptr dereference in port callbacks */
2031 		spin_lock(&release_lock);
2032 		mos_parport->pp->private_data = NULL;
2033 		spin_unlock(&release_lock);
2034 
2035 		/* wait for synchronous usb calls to return */
2036 		if (mos_parport->msg_pending)
2037 			wait_for_completion_timeout(&mos_parport->syncmsg_compl,
2038 						    MOS_WDR_TIMEOUT);
2039 
2040 		parport_remove_port(mos_parport->pp);
2041 		usb_set_serial_data(serial, NULL);
2042 		mos_parport->serial = NULL;
2043 
2044 		/* if tasklet currently scheduled, wait for it to complete */
2045 		tasklet_kill(&mos_parport->urb_tasklet);
2046 
2047 		/* unlink any urbs sent by the tasklet  */
2048 		spin_lock_irqsave(&mos_parport->listlock, flags);
2049 		list_for_each_entry(urbtrack,
2050 				    &mos_parport->active_urbs,
2051 				    urblist_entry)
2052 			usb_unlink_urb(urbtrack->urb);
2053 		spin_unlock_irqrestore(&mos_parport->listlock, flags);
2054 
2055 		kref_put(&mos_parport->ref_count, destroy_mos_parport);
2056 	}
2057 #endif
2058 }
2059 
2060 static int mos7720_port_probe(struct usb_serial_port *port)
2061 {
2062 	struct moschip_port *mos7720_port;
2063 
2064 	mos7720_port = kzalloc(sizeof(*mos7720_port), GFP_KERNEL);
2065 	if (!mos7720_port)
2066 		return -ENOMEM;
2067 
2068 	/* Initialize all port interrupt end point to port 0 int endpoint.
2069 	 * Our device has only one interrupt endpoint common to all ports.
2070 	 */
2071 	port->interrupt_in_endpointAddress =
2072 		port->serial->port[0]->interrupt_in_endpointAddress;
2073 	mos7720_port->port = port;
2074 
2075 	usb_set_serial_port_data(port, mos7720_port);
2076 
2077 	return 0;
2078 }
2079 
2080 static int mos7720_port_remove(struct usb_serial_port *port)
2081 {
2082 	struct moschip_port *mos7720_port;
2083 
2084 	mos7720_port = usb_get_serial_port_data(port);
2085 	kfree(mos7720_port);
2086 
2087 	return 0;
2088 }
2089 
2090 static struct usb_serial_driver moschip7720_2port_driver = {
2091 	.driver = {
2092 		.owner =	THIS_MODULE,
2093 		.name =		"moschip7720",
2094 	},
2095 	.description		= "Moschip 2 port adapter",
2096 	.id_table		= id_table,
2097 	.calc_num_ports		= mos77xx_calc_num_ports,
2098 	.open			= mos7720_open,
2099 	.close			= mos7720_close,
2100 	.throttle		= mos7720_throttle,
2101 	.unthrottle		= mos7720_unthrottle,
2102 	.probe			= mos77xx_probe,
2103 	.attach			= mos7720_startup,
2104 	.release		= mos7720_release,
2105 	.port_probe		= mos7720_port_probe,
2106 	.port_remove		= mos7720_port_remove,
2107 	.ioctl			= mos7720_ioctl,
2108 	.tiocmget		= mos7720_tiocmget,
2109 	.tiocmset		= mos7720_tiocmset,
2110 	.get_icount		= mos7720_get_icount,
2111 	.set_termios		= mos7720_set_termios,
2112 	.write			= mos7720_write,
2113 	.write_room		= mos7720_write_room,
2114 	.chars_in_buffer	= mos7720_chars_in_buffer,
2115 	.break_ctl		= mos7720_break,
2116 	.read_bulk_callback	= mos7720_bulk_in_callback,
2117 	.read_int_callback	= NULL  /* dynamically assigned in probe() */
2118 };
2119 
2120 static struct usb_serial_driver * const serial_drivers[] = {
2121 	&moschip7720_2port_driver, NULL
2122 };
2123 
2124 module_usb_serial_driver(serial_drivers, id_table);
2125 
2126 MODULE_AUTHOR(DRIVER_AUTHOR);
2127 MODULE_DESCRIPTION(DRIVER_DESC);
2128 MODULE_LICENSE("GPL");
2129