xref: /linux/drivers/usb/serial/mos7720.c (revision 3ce095c16263630dde46d6051854073edaacf3d7)
1 /*
2  * mos7720.c
3  *   Controls the Moschip 7720 usb to dual port serial converter
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/slab.h>
26 #include <linux/tty.h>
27 #include <linux/tty_driver.h>
28 #include <linux/tty_flip.h>
29 #include <linux/module.h>
30 #include <linux/spinlock.h>
31 #include <linux/serial.h>
32 #include <linux/serial_reg.h>
33 #include <linux/usb.h>
34 #include <linux/usb/serial.h>
35 #include <linux/uaccess.h>
36 #include <linux/parport.h>
37 
38 #define DRIVER_AUTHOR "Aspire Communications pvt Ltd."
39 #define DRIVER_DESC "Moschip USB Serial Driver"
40 
41 /* default urb timeout */
42 #define MOS_WDR_TIMEOUT	5000
43 
44 #define MOS_MAX_PORT	0x02
45 #define MOS_WRITE	0x0E
46 #define MOS_READ	0x0D
47 
48 /* Interrupt Routines Defines	*/
49 #define SERIAL_IIR_RLS	0x06
50 #define SERIAL_IIR_RDA	0x04
51 #define SERIAL_IIR_CTI	0x0c
52 #define SERIAL_IIR_THR	0x02
53 #define SERIAL_IIR_MS	0x00
54 
55 #define NUM_URBS			16	/* URB Count */
56 #define URB_TRANSFER_BUFFER_SIZE	32	/* URB Size */
57 
58 /* This structure holds all of the local serial port information */
59 struct moschip_port {
60 	__u8	shadowLCR;		/* last LCR value received */
61 	__u8	shadowMCR;		/* last MCR value received */
62 	__u8	shadowMSR;		/* last MSR value received */
63 	char			open;
64 	struct usb_serial_port	*port;	/* loop back to the owner */
65 	struct urb		*write_urb_pool[NUM_URBS];
66 };
67 
68 static struct usb_serial_driver moschip7720_2port_driver;
69 
70 #define USB_VENDOR_ID_MOSCHIP		0x9710
71 #define MOSCHIP_DEVICE_ID_7720		0x7720
72 #define MOSCHIP_DEVICE_ID_7715		0x7715
73 
74 static const struct usb_device_id id_table[] = {
75 	{ USB_DEVICE(USB_VENDOR_ID_MOSCHIP, MOSCHIP_DEVICE_ID_7720) },
76 	{ USB_DEVICE(USB_VENDOR_ID_MOSCHIP, MOSCHIP_DEVICE_ID_7715) },
77 	{ } /* terminating entry */
78 };
79 MODULE_DEVICE_TABLE(usb, id_table);
80 
81 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
82 
83 /* initial values for parport regs */
84 #define DCR_INIT_VAL       0x0c	/* SLCTIN, nINIT */
85 #define ECR_INIT_VAL       0x00	/* SPP mode */
86 
87 struct urbtracker {
88 	struct mos7715_parport  *mos_parport;
89 	struct list_head        urblist_entry;
90 	struct kref             ref_count;
91 	struct urb              *urb;
92 	struct usb_ctrlrequest	*setup;
93 };
94 
95 enum mos7715_pp_modes {
96 	SPP = 0<<5,
97 	PS2 = 1<<5,      /* moschip calls this 'NIBBLE' mode */
98 	PPF = 2<<5,	 /* moschip calls this 'CB-FIFO mode */
99 };
100 
101 struct mos7715_parport {
102 	struct parport          *pp;	       /* back to containing struct */
103 	struct kref             ref_count;     /* to instance of this struct */
104 	struct list_head        deferred_urbs; /* list deferred async urbs */
105 	struct list_head        active_urbs;   /* list async urbs in flight */
106 	spinlock_t              listlock;      /* protects list access */
107 	bool                    msg_pending;   /* usb sync call pending */
108 	struct completion       syncmsg_compl; /* usb sync call completed */
109 	struct tasklet_struct   urb_tasklet;   /* for sending deferred urbs */
110 	struct usb_serial       *serial;       /* back to containing struct */
111 	__u8	                shadowECR;     /* parallel port regs... */
112 	__u8	                shadowDCR;
113 	atomic_t                shadowDSR;     /* updated in int-in callback */
114 };
115 
116 /* lock guards against dereferencing NULL ptr in parport ops callbacks */
117 static DEFINE_SPINLOCK(release_lock);
118 
119 #endif	/* CONFIG_USB_SERIAL_MOS7715_PARPORT */
120 
121 static const unsigned int dummy; /* for clarity in register access fns */
122 
123 enum mos_regs {
124 	THR,	          /* serial port regs */
125 	RHR,
126 	IER,
127 	FCR,
128 	ISR,
129 	LCR,
130 	MCR,
131 	LSR,
132 	MSR,
133 	SPR,
134 	DLL,
135 	DLM,
136 	DPR,              /* parallel port regs */
137 	DSR,
138 	DCR,
139 	ECR,
140 	SP1_REG,          /* device control regs */
141 	SP2_REG,          /* serial port 2 (7720 only) */
142 	PP_REG,
143 	SP_CONTROL_REG,
144 };
145 
146 /*
147  * Return the correct value for the Windex field of the setup packet
148  * for a control endpoint message.  See the 7715 datasheet.
149  */
150 static inline __u16 get_reg_index(enum mos_regs reg)
151 {
152 	static const __u16 mos7715_index_lookup_table[] = {
153 		0x00,		/* THR */
154 		0x00,		/* RHR */
155 		0x01,		/* IER */
156 		0x02,		/* FCR */
157 		0x02,		/* ISR */
158 		0x03,		/* LCR */
159 		0x04,		/* MCR */
160 		0x05,		/* LSR */
161 		0x06,		/* MSR */
162 		0x07,		/* SPR */
163 		0x00,		/* DLL */
164 		0x01,		/* DLM */
165 		0x00,		/* DPR */
166 		0x01,		/* DSR */
167 		0x02,		/* DCR */
168 		0x0a,		/* ECR */
169 		0x01,		/* SP1_REG */
170 		0x02,		/* SP2_REG (7720 only) */
171 		0x04,		/* PP_REG (7715 only) */
172 		0x08,		/* SP_CONTROL_REG */
173 	};
174 	return mos7715_index_lookup_table[reg];
175 }
176 
177 /*
178  * Return the correct value for the upper byte of the Wvalue field of
179  * the setup packet for a control endpoint message.
180  */
181 static inline __u16 get_reg_value(enum mos_regs reg,
182 				  unsigned int serial_portnum)
183 {
184 	if (reg >= SP1_REG)	      /* control reg */
185 		return 0x0000;
186 
187 	else if (reg >= DPR)	      /* parallel port reg (7715 only) */
188 		return 0x0100;
189 
190 	else			      /* serial port reg */
191 		return (serial_portnum + 2) << 8;
192 }
193 
194 /*
195  * Write data byte to the specified device register.  The data is embedded in
196  * the value field of the setup packet. serial_portnum is ignored for registers
197  * not specific to a particular serial port.
198  */
199 static int write_mos_reg(struct usb_serial *serial, unsigned int serial_portnum,
200 			 enum mos_regs reg, __u8 data)
201 {
202 	struct usb_device *usbdev = serial->dev;
203 	unsigned int pipe = usb_sndctrlpipe(usbdev, 0);
204 	__u8 request = (__u8)0x0e;
205 	__u8 requesttype = (__u8)0x40;
206 	__u16 index = get_reg_index(reg);
207 	__u16 value = get_reg_value(reg, serial_portnum) + data;
208 	int status = usb_control_msg(usbdev, pipe, request, requesttype, value,
209 				     index, NULL, 0, MOS_WDR_TIMEOUT);
210 	if (status < 0)
211 		dev_err(&usbdev->dev,
212 			"mos7720: usb_control_msg() failed: %d\n", status);
213 	return status;
214 }
215 
216 /*
217  * Read data byte from the specified device register.  The data returned by the
218  * device is embedded in the value field of the setup packet.  serial_portnum is
219  * ignored for registers that are not specific to a particular serial port.
220  */
221 static int read_mos_reg(struct usb_serial *serial, unsigned int serial_portnum,
222 			enum mos_regs reg, __u8 *data)
223 {
224 	struct usb_device *usbdev = serial->dev;
225 	unsigned int pipe = usb_rcvctrlpipe(usbdev, 0);
226 	__u8 request = (__u8)0x0d;
227 	__u8 requesttype = (__u8)0xc0;
228 	__u16 index = get_reg_index(reg);
229 	__u16 value = get_reg_value(reg, serial_portnum);
230 	u8 *buf;
231 	int status;
232 
233 	buf = kmalloc(1, GFP_KERNEL);
234 	if (!buf)
235 		return -ENOMEM;
236 
237 	status = usb_control_msg(usbdev, pipe, request, requesttype, value,
238 				     index, buf, 1, MOS_WDR_TIMEOUT);
239 	if (status == 1)
240 		*data = *buf;
241 	else if (status < 0)
242 		dev_err(&usbdev->dev,
243 			"mos7720: usb_control_msg() failed: %d\n", status);
244 	kfree(buf);
245 
246 	return status;
247 }
248 
249 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
250 
251 static inline int mos7715_change_mode(struct mos7715_parport *mos_parport,
252 				      enum mos7715_pp_modes mode)
253 {
254 	mos_parport->shadowECR = mode;
255 	write_mos_reg(mos_parport->serial, dummy, ECR, mos_parport->shadowECR);
256 	return 0;
257 }
258 
259 static void destroy_mos_parport(struct kref *kref)
260 {
261 	struct mos7715_parport *mos_parport =
262 		container_of(kref, struct mos7715_parport, ref_count);
263 
264 	kfree(mos_parport);
265 }
266 
267 static void destroy_urbtracker(struct kref *kref)
268 {
269 	struct urbtracker *urbtrack =
270 		container_of(kref, struct urbtracker, ref_count);
271 	struct mos7715_parport *mos_parport = urbtrack->mos_parport;
272 
273 	usb_free_urb(urbtrack->urb);
274 	kfree(urbtrack->setup);
275 	kfree(urbtrack);
276 	kref_put(&mos_parport->ref_count, destroy_mos_parport);
277 }
278 
279 /*
280  * This runs as a tasklet when sending an urb in a non-blocking parallel
281  * port callback had to be deferred because the disconnect mutex could not be
282  * obtained at the time.
283  */
284 static void send_deferred_urbs(unsigned long _mos_parport)
285 {
286 	int ret_val;
287 	unsigned long flags;
288 	struct mos7715_parport *mos_parport = (void *)_mos_parport;
289 	struct urbtracker *urbtrack, *tmp;
290 	struct list_head *cursor, *next;
291 	struct device *dev;
292 
293 	/* if release function ran, game over */
294 	if (unlikely(mos_parport->serial == NULL))
295 		return;
296 
297 	dev = &mos_parport->serial->dev->dev;
298 
299 	/* try again to get the mutex */
300 	if (!mutex_trylock(&mos_parport->serial->disc_mutex)) {
301 		dev_dbg(dev, "%s: rescheduling tasklet\n", __func__);
302 		tasklet_schedule(&mos_parport->urb_tasklet);
303 		return;
304 	}
305 
306 	/* if device disconnected, game over */
307 	if (unlikely(mos_parport->serial->disconnected)) {
308 		mutex_unlock(&mos_parport->serial->disc_mutex);
309 		return;
310 	}
311 
312 	spin_lock_irqsave(&mos_parport->listlock, flags);
313 	if (list_empty(&mos_parport->deferred_urbs)) {
314 		spin_unlock_irqrestore(&mos_parport->listlock, flags);
315 		mutex_unlock(&mos_parport->serial->disc_mutex);
316 		dev_dbg(dev, "%s: deferred_urbs list empty\n", __func__);
317 		return;
318 	}
319 
320 	/* move contents of deferred_urbs list to active_urbs list and submit */
321 	list_for_each_safe(cursor, next, &mos_parport->deferred_urbs)
322 		list_move_tail(cursor, &mos_parport->active_urbs);
323 	list_for_each_entry_safe(urbtrack, tmp, &mos_parport->active_urbs,
324 			    urblist_entry) {
325 		ret_val = usb_submit_urb(urbtrack->urb, GFP_ATOMIC);
326 		dev_dbg(dev, "%s: urb submitted\n", __func__);
327 		if (ret_val) {
328 			dev_err(dev, "usb_submit_urb() failed: %d\n", ret_val);
329 			list_del(&urbtrack->urblist_entry);
330 			kref_put(&urbtrack->ref_count, destroy_urbtracker);
331 		}
332 	}
333 	spin_unlock_irqrestore(&mos_parport->listlock, flags);
334 	mutex_unlock(&mos_parport->serial->disc_mutex);
335 }
336 
337 /* callback for parallel port control urbs submitted asynchronously */
338 static void async_complete(struct urb *urb)
339 {
340 	struct urbtracker *urbtrack = urb->context;
341 	int status = urb->status;
342 
343 	if (unlikely(status))
344 		dev_dbg(&urb->dev->dev, "%s - nonzero urb status received: %d\n", __func__, status);
345 
346 	/* remove the urbtracker from the active_urbs list */
347 	spin_lock(&urbtrack->mos_parport->listlock);
348 	list_del(&urbtrack->urblist_entry);
349 	spin_unlock(&urbtrack->mos_parport->listlock);
350 	kref_put(&urbtrack->ref_count, destroy_urbtracker);
351 }
352 
353 static int write_parport_reg_nonblock(struct mos7715_parport *mos_parport,
354 				      enum mos_regs reg, __u8 data)
355 {
356 	struct urbtracker *urbtrack;
357 	int ret_val;
358 	unsigned long flags;
359 	struct usb_serial *serial = mos_parport->serial;
360 	struct usb_device *usbdev = serial->dev;
361 
362 	/* create and initialize the control urb and containing urbtracker */
363 	urbtrack = kmalloc(sizeof(struct urbtracker), GFP_ATOMIC);
364 	if (!urbtrack)
365 		return -ENOMEM;
366 
367 	kref_get(&mos_parport->ref_count);
368 	urbtrack->mos_parport = mos_parport;
369 	urbtrack->urb = usb_alloc_urb(0, GFP_ATOMIC);
370 	if (!urbtrack->urb) {
371 		kfree(urbtrack);
372 		return -ENOMEM;
373 	}
374 	urbtrack->setup = kmalloc(sizeof(*urbtrack->setup), GFP_ATOMIC);
375 	if (!urbtrack->setup) {
376 		usb_free_urb(urbtrack->urb);
377 		kfree(urbtrack);
378 		return -ENOMEM;
379 	}
380 	urbtrack->setup->bRequestType = (__u8)0x40;
381 	urbtrack->setup->bRequest = (__u8)0x0e;
382 	urbtrack->setup->wValue = cpu_to_le16(get_reg_value(reg, dummy));
383 	urbtrack->setup->wIndex = cpu_to_le16(get_reg_index(reg));
384 	urbtrack->setup->wLength = 0;
385 	usb_fill_control_urb(urbtrack->urb, usbdev,
386 			     usb_sndctrlpipe(usbdev, 0),
387 			     (unsigned char *)urbtrack->setup,
388 			     NULL, 0, async_complete, urbtrack);
389 	kref_init(&urbtrack->ref_count);
390 	INIT_LIST_HEAD(&urbtrack->urblist_entry);
391 
392 	/*
393 	 * get the disconnect mutex, or add tracker to the deferred_urbs list
394 	 * and schedule a tasklet to try again later
395 	 */
396 	if (!mutex_trylock(&serial->disc_mutex)) {
397 		spin_lock_irqsave(&mos_parport->listlock, flags);
398 		list_add_tail(&urbtrack->urblist_entry,
399 			      &mos_parport->deferred_urbs);
400 		spin_unlock_irqrestore(&mos_parport->listlock, flags);
401 		tasklet_schedule(&mos_parport->urb_tasklet);
402 		dev_dbg(&usbdev->dev, "tasklet scheduled\n");
403 		return 0;
404 	}
405 
406 	/* bail if device disconnected */
407 	if (serial->disconnected) {
408 		kref_put(&urbtrack->ref_count, destroy_urbtracker);
409 		mutex_unlock(&serial->disc_mutex);
410 		return -ENODEV;
411 	}
412 
413 	/* add the tracker to the active_urbs list and submit */
414 	spin_lock_irqsave(&mos_parport->listlock, flags);
415 	list_add_tail(&urbtrack->urblist_entry, &mos_parport->active_urbs);
416 	spin_unlock_irqrestore(&mos_parport->listlock, flags);
417 	ret_val = usb_submit_urb(urbtrack->urb, GFP_ATOMIC);
418 	mutex_unlock(&serial->disc_mutex);
419 	if (ret_val) {
420 		dev_err(&usbdev->dev,
421 			"%s: submit_urb() failed: %d\n", __func__, ret_val);
422 		spin_lock_irqsave(&mos_parport->listlock, flags);
423 		list_del(&urbtrack->urblist_entry);
424 		spin_unlock_irqrestore(&mos_parport->listlock, flags);
425 		kref_put(&urbtrack->ref_count, destroy_urbtracker);
426 		return ret_val;
427 	}
428 	return 0;
429 }
430 
431 /*
432  * This is the the common top part of all parallel port callback operations that
433  * send synchronous messages to the device.  This implements convoluted locking
434  * that avoids two scenarios: (1) a port operation is called after usbserial
435  * has called our release function, at which point struct mos7715_parport has
436  * been destroyed, and (2) the device has been disconnected, but usbserial has
437  * not called the release function yet because someone has a serial port open.
438  * The shared release_lock prevents the first, and the mutex and disconnected
439  * flag maintained by usbserial covers the second.  We also use the msg_pending
440  * flag to ensure that all synchronous usb message calls have completed before
441  * our release function can return.
442  */
443 static int parport_prologue(struct parport *pp)
444 {
445 	struct mos7715_parport *mos_parport;
446 
447 	spin_lock(&release_lock);
448 	mos_parport = pp->private_data;
449 	if (unlikely(mos_parport == NULL)) {
450 		/* release fn called, port struct destroyed */
451 		spin_unlock(&release_lock);
452 		return -1;
453 	}
454 	mos_parport->msg_pending = true;   /* synch usb call pending */
455 	reinit_completion(&mos_parport->syncmsg_compl);
456 	spin_unlock(&release_lock);
457 
458 	mutex_lock(&mos_parport->serial->disc_mutex);
459 	if (mos_parport->serial->disconnected) {
460 		/* device disconnected */
461 		mutex_unlock(&mos_parport->serial->disc_mutex);
462 		mos_parport->msg_pending = false;
463 		complete(&mos_parport->syncmsg_compl);
464 		return -1;
465 	}
466 
467 	return 0;
468 }
469 
470 /*
471  * This is the common bottom part of all parallel port functions that send
472  * synchronous messages to the device.
473  */
474 static inline void parport_epilogue(struct parport *pp)
475 {
476 	struct mos7715_parport *mos_parport = pp->private_data;
477 	mutex_unlock(&mos_parport->serial->disc_mutex);
478 	mos_parport->msg_pending = false;
479 	complete(&mos_parport->syncmsg_compl);
480 }
481 
482 static void parport_mos7715_write_data(struct parport *pp, unsigned char d)
483 {
484 	struct mos7715_parport *mos_parport = pp->private_data;
485 
486 	if (parport_prologue(pp) < 0)
487 		return;
488 	mos7715_change_mode(mos_parport, SPP);
489 	write_mos_reg(mos_parport->serial, dummy, DPR, (__u8)d);
490 	parport_epilogue(pp);
491 }
492 
493 static unsigned char parport_mos7715_read_data(struct parport *pp)
494 {
495 	struct mos7715_parport *mos_parport = pp->private_data;
496 	unsigned char d;
497 
498 	if (parport_prologue(pp) < 0)
499 		return 0;
500 	read_mos_reg(mos_parport->serial, dummy, DPR, &d);
501 	parport_epilogue(pp);
502 	return d;
503 }
504 
505 static void parport_mos7715_write_control(struct parport *pp, unsigned char d)
506 {
507 	struct mos7715_parport *mos_parport = pp->private_data;
508 	__u8 data;
509 
510 	if (parport_prologue(pp) < 0)
511 		return;
512 	data = ((__u8)d & 0x0f) | (mos_parport->shadowDCR & 0xf0);
513 	write_mos_reg(mos_parport->serial, dummy, DCR, data);
514 	mos_parport->shadowDCR = data;
515 	parport_epilogue(pp);
516 }
517 
518 static unsigned char parport_mos7715_read_control(struct parport *pp)
519 {
520 	struct mos7715_parport *mos_parport = pp->private_data;
521 	__u8 dcr;
522 
523 	spin_lock(&release_lock);
524 	mos_parport = pp->private_data;
525 	if (unlikely(mos_parport == NULL)) {
526 		spin_unlock(&release_lock);
527 		return 0;
528 	}
529 	dcr = mos_parport->shadowDCR & 0x0f;
530 	spin_unlock(&release_lock);
531 	return dcr;
532 }
533 
534 static unsigned char parport_mos7715_frob_control(struct parport *pp,
535 						  unsigned char mask,
536 						  unsigned char val)
537 {
538 	struct mos7715_parport *mos_parport = pp->private_data;
539 	__u8 dcr;
540 
541 	mask &= 0x0f;
542 	val &= 0x0f;
543 	if (parport_prologue(pp) < 0)
544 		return 0;
545 	mos_parport->shadowDCR = (mos_parport->shadowDCR & (~mask)) ^ val;
546 	write_mos_reg(mos_parport->serial, dummy, DCR, mos_parport->shadowDCR);
547 	dcr = mos_parport->shadowDCR & 0x0f;
548 	parport_epilogue(pp);
549 	return dcr;
550 }
551 
552 static unsigned char parport_mos7715_read_status(struct parport *pp)
553 {
554 	unsigned char status;
555 	struct mos7715_parport *mos_parport = pp->private_data;
556 
557 	spin_lock(&release_lock);
558 	mos_parport = pp->private_data;
559 	if (unlikely(mos_parport == NULL)) {	/* release called */
560 		spin_unlock(&release_lock);
561 		return 0;
562 	}
563 	status = atomic_read(&mos_parport->shadowDSR) & 0xf8;
564 	spin_unlock(&release_lock);
565 	return status;
566 }
567 
568 static void parport_mos7715_enable_irq(struct parport *pp)
569 {
570 }
571 
572 static void parport_mos7715_disable_irq(struct parport *pp)
573 {
574 }
575 
576 static void parport_mos7715_data_forward(struct parport *pp)
577 {
578 	struct mos7715_parport *mos_parport = pp->private_data;
579 
580 	if (parport_prologue(pp) < 0)
581 		return;
582 	mos7715_change_mode(mos_parport, PS2);
583 	mos_parport->shadowDCR &=  ~0x20;
584 	write_mos_reg(mos_parport->serial, dummy, DCR, mos_parport->shadowDCR);
585 	parport_epilogue(pp);
586 }
587 
588 static void parport_mos7715_data_reverse(struct parport *pp)
589 {
590 	struct mos7715_parport *mos_parport = pp->private_data;
591 
592 	if (parport_prologue(pp) < 0)
593 		return;
594 	mos7715_change_mode(mos_parport, PS2);
595 	mos_parport->shadowDCR |= 0x20;
596 	write_mos_reg(mos_parport->serial, dummy, DCR, mos_parport->shadowDCR);
597 	parport_epilogue(pp);
598 }
599 
600 static void parport_mos7715_init_state(struct pardevice *dev,
601 				       struct parport_state *s)
602 {
603 	s->u.pc.ctr = DCR_INIT_VAL;
604 	s->u.pc.ecr = ECR_INIT_VAL;
605 }
606 
607 /* N.B. Parport core code requires that this function not block */
608 static void parport_mos7715_save_state(struct parport *pp,
609 				       struct parport_state *s)
610 {
611 	struct mos7715_parport *mos_parport;
612 
613 	spin_lock(&release_lock);
614 	mos_parport = pp->private_data;
615 	if (unlikely(mos_parport == NULL)) {	/* release called */
616 		spin_unlock(&release_lock);
617 		return;
618 	}
619 	s->u.pc.ctr = mos_parport->shadowDCR;
620 	s->u.pc.ecr = mos_parport->shadowECR;
621 	spin_unlock(&release_lock);
622 }
623 
624 /* N.B. Parport core code requires that this function not block */
625 static void parport_mos7715_restore_state(struct parport *pp,
626 					  struct parport_state *s)
627 {
628 	struct mos7715_parport *mos_parport;
629 
630 	spin_lock(&release_lock);
631 	mos_parport = pp->private_data;
632 	if (unlikely(mos_parport == NULL)) {	/* release called */
633 		spin_unlock(&release_lock);
634 		return;
635 	}
636 	write_parport_reg_nonblock(mos_parport, DCR, mos_parport->shadowDCR);
637 	write_parport_reg_nonblock(mos_parport, ECR, mos_parport->shadowECR);
638 	spin_unlock(&release_lock);
639 }
640 
641 static size_t parport_mos7715_write_compat(struct parport *pp,
642 					   const void *buffer,
643 					   size_t len, int flags)
644 {
645 	int retval;
646 	struct mos7715_parport *mos_parport = pp->private_data;
647 	int actual_len;
648 
649 	if (parport_prologue(pp) < 0)
650 		return 0;
651 	mos7715_change_mode(mos_parport, PPF);
652 	retval = usb_bulk_msg(mos_parport->serial->dev,
653 			      usb_sndbulkpipe(mos_parport->serial->dev, 2),
654 			      (void *)buffer, len, &actual_len,
655 			      MOS_WDR_TIMEOUT);
656 	parport_epilogue(pp);
657 	if (retval) {
658 		dev_err(&mos_parport->serial->dev->dev,
659 			"mos7720: usb_bulk_msg() failed: %d\n", retval);
660 		return 0;
661 	}
662 	return actual_len;
663 }
664 
665 static struct parport_operations parport_mos7715_ops = {
666 	.owner =		THIS_MODULE,
667 	.write_data =		parport_mos7715_write_data,
668 	.read_data =		parport_mos7715_read_data,
669 
670 	.write_control =	parport_mos7715_write_control,
671 	.read_control =		parport_mos7715_read_control,
672 	.frob_control =		parport_mos7715_frob_control,
673 
674 	.read_status =		parport_mos7715_read_status,
675 
676 	.enable_irq =		parport_mos7715_enable_irq,
677 	.disable_irq =		parport_mos7715_disable_irq,
678 
679 	.data_forward =		parport_mos7715_data_forward,
680 	.data_reverse =		parport_mos7715_data_reverse,
681 
682 	.init_state =		parport_mos7715_init_state,
683 	.save_state =		parport_mos7715_save_state,
684 	.restore_state =	parport_mos7715_restore_state,
685 
686 	.compat_write_data =	parport_mos7715_write_compat,
687 
688 	.nibble_read_data =	parport_ieee1284_read_nibble,
689 	.byte_read_data =	parport_ieee1284_read_byte,
690 };
691 
692 /*
693  * Allocate and initialize parallel port control struct, initialize
694  * the parallel port hardware device, and register with the parport subsystem.
695  */
696 static int mos7715_parport_init(struct usb_serial *serial)
697 {
698 	struct mos7715_parport *mos_parport;
699 
700 	/* allocate and initialize parallel port control struct */
701 	mos_parport = kzalloc(sizeof(struct mos7715_parport), GFP_KERNEL);
702 	if (!mos_parport)
703 		return -ENOMEM;
704 
705 	mos_parport->msg_pending = false;
706 	kref_init(&mos_parport->ref_count);
707 	spin_lock_init(&mos_parport->listlock);
708 	INIT_LIST_HEAD(&mos_parport->active_urbs);
709 	INIT_LIST_HEAD(&mos_parport->deferred_urbs);
710 	usb_set_serial_data(serial, mos_parport); /* hijack private pointer */
711 	mos_parport->serial = serial;
712 	tasklet_init(&mos_parport->urb_tasklet, send_deferred_urbs,
713 		     (unsigned long) mos_parport);
714 	init_completion(&mos_parport->syncmsg_compl);
715 
716 	/* cycle parallel port reset bit */
717 	write_mos_reg(mos_parport->serial, dummy, PP_REG, (__u8)0x80);
718 	write_mos_reg(mos_parport->serial, dummy, PP_REG, (__u8)0x00);
719 
720 	/* initialize device registers */
721 	mos_parport->shadowDCR = DCR_INIT_VAL;
722 	write_mos_reg(mos_parport->serial, dummy, DCR, mos_parport->shadowDCR);
723 	mos_parport->shadowECR = ECR_INIT_VAL;
724 	write_mos_reg(mos_parport->serial, dummy, ECR, mos_parport->shadowECR);
725 
726 	/* register with parport core */
727 	mos_parport->pp = parport_register_port(0, PARPORT_IRQ_NONE,
728 						PARPORT_DMA_NONE,
729 						&parport_mos7715_ops);
730 	if (mos_parport->pp == NULL) {
731 		dev_err(&serial->interface->dev,
732 			"Could not register parport\n");
733 		kref_put(&mos_parport->ref_count, destroy_mos_parport);
734 		return -EIO;
735 	}
736 	mos_parport->pp->private_data = mos_parport;
737 	mos_parport->pp->modes = PARPORT_MODE_COMPAT | PARPORT_MODE_PCSPP;
738 	mos_parport->pp->dev = &serial->interface->dev;
739 	parport_announce_port(mos_parport->pp);
740 
741 	return 0;
742 }
743 #endif	/* CONFIG_USB_SERIAL_MOS7715_PARPORT */
744 
745 /*
746  * mos7720_interrupt_callback
747  *	this is the callback function for when we have received data on the
748  *	interrupt endpoint.
749  */
750 static void mos7720_interrupt_callback(struct urb *urb)
751 {
752 	int result;
753 	int length;
754 	int status = urb->status;
755 	struct device *dev = &urb->dev->dev;
756 	__u8 *data;
757 	__u8 sp1;
758 	__u8 sp2;
759 
760 	switch (status) {
761 	case 0:
762 		/* success */
763 		break;
764 	case -ECONNRESET:
765 	case -ENOENT:
766 	case -ESHUTDOWN:
767 		/* this urb is terminated, clean up */
768 		dev_dbg(dev, "%s - urb shutting down with status: %d\n", __func__, status);
769 		return;
770 	default:
771 		dev_dbg(dev, "%s - nonzero urb status received: %d\n", __func__, status);
772 		goto exit;
773 	}
774 
775 	length = urb->actual_length;
776 	data = urb->transfer_buffer;
777 
778 	/* Moschip get 4 bytes
779 	 * Byte 1 IIR Port 1 (port.number is 0)
780 	 * Byte 2 IIR Port 2 (port.number is 1)
781 	 * Byte 3 --------------
782 	 * Byte 4 FIFO status for both */
783 
784 	/* the above description is inverted
785 	 * 	oneukum 2007-03-14 */
786 
787 	if (unlikely(length != 4)) {
788 		dev_dbg(dev, "Wrong data !!!\n");
789 		return;
790 	}
791 
792 	sp1 = data[3];
793 	sp2 = data[2];
794 
795 	if ((sp1 | sp2) & 0x01) {
796 		/* No Interrupt Pending in both the ports */
797 		dev_dbg(dev, "No Interrupt !!!\n");
798 	} else {
799 		switch (sp1 & 0x0f) {
800 		case SERIAL_IIR_RLS:
801 			dev_dbg(dev, "Serial Port 1: Receiver status error or address bit detected in 9-bit mode\n");
802 			break;
803 		case SERIAL_IIR_CTI:
804 			dev_dbg(dev, "Serial Port 1: Receiver time out\n");
805 			break;
806 		case SERIAL_IIR_MS:
807 			/* dev_dbg(dev, "Serial Port 1: Modem status change\n"); */
808 			break;
809 		}
810 
811 		switch (sp2 & 0x0f) {
812 		case SERIAL_IIR_RLS:
813 			dev_dbg(dev, "Serial Port 2: Receiver status error or address bit detected in 9-bit mode\n");
814 			break;
815 		case SERIAL_IIR_CTI:
816 			dev_dbg(dev, "Serial Port 2: Receiver time out\n");
817 			break;
818 		case SERIAL_IIR_MS:
819 			/* dev_dbg(dev, "Serial Port 2: Modem status change\n"); */
820 			break;
821 		}
822 	}
823 
824 exit:
825 	result = usb_submit_urb(urb, GFP_ATOMIC);
826 	if (result)
827 		dev_err(dev, "%s - Error %d submitting control urb\n", __func__, result);
828 }
829 
830 /*
831  * mos7715_interrupt_callback
832  *	this is the 7715's callback function for when we have received data on
833  *	the interrupt endpoint.
834  */
835 static void mos7715_interrupt_callback(struct urb *urb)
836 {
837 	int result;
838 	int length;
839 	int status = urb->status;
840 	struct device *dev = &urb->dev->dev;
841 	__u8 *data;
842 	__u8 iir;
843 
844 	switch (status) {
845 	case 0:
846 		/* success */
847 		break;
848 	case -ECONNRESET:
849 	case -ENOENT:
850 	case -ESHUTDOWN:
851 	case -ENODEV:
852 		/* this urb is terminated, clean up */
853 		dev_dbg(dev, "%s - urb shutting down with status: %d\n", __func__, status);
854 		return;
855 	default:
856 		dev_dbg(dev, "%s - nonzero urb status received: %d\n", __func__, status);
857 		goto exit;
858 	}
859 
860 	length = urb->actual_length;
861 	data = urb->transfer_buffer;
862 
863 	/* Structure of data from 7715 device:
864 	 * Byte 1: IIR serial Port
865 	 * Byte 2: unused
866 	 * Byte 2: DSR parallel port
867 	 * Byte 4: FIFO status for both */
868 
869 	if (unlikely(length != 4)) {
870 		dev_dbg(dev, "Wrong data !!!\n");
871 		return;
872 	}
873 
874 	iir = data[0];
875 	if (!(iir & 0x01)) {	/* serial port interrupt pending */
876 		switch (iir & 0x0f) {
877 		case SERIAL_IIR_RLS:
878 			dev_dbg(dev, "Serial Port: Receiver status error or address bit detected in 9-bit mode\n");
879 			break;
880 		case SERIAL_IIR_CTI:
881 			dev_dbg(dev, "Serial Port: Receiver time out\n");
882 			break;
883 		case SERIAL_IIR_MS:
884 			/* dev_dbg(dev, "Serial Port: Modem status change\n"); */
885 			break;
886 		}
887 	}
888 
889 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
890 	{       /* update local copy of DSR reg */
891 		struct usb_serial_port *port = urb->context;
892 		struct mos7715_parport *mos_parport = port->serial->private;
893 		if (unlikely(mos_parport == NULL))
894 			return;
895 		atomic_set(&mos_parport->shadowDSR, data[2]);
896 	}
897 #endif
898 
899 exit:
900 	result = usb_submit_urb(urb, GFP_ATOMIC);
901 	if (result)
902 		dev_err(dev, "%s - Error %d submitting control urb\n", __func__, result);
903 }
904 
905 /*
906  * mos7720_bulk_in_callback
907  *	this is the callback function for when we have received data on the
908  *	bulk in endpoint.
909  */
910 static void mos7720_bulk_in_callback(struct urb *urb)
911 {
912 	int retval;
913 	unsigned char *data ;
914 	struct usb_serial_port *port;
915 	int status = urb->status;
916 
917 	if (status) {
918 		dev_dbg(&urb->dev->dev, "nonzero read bulk status received: %d\n", status);
919 		return;
920 	}
921 
922 	port = urb->context;
923 
924 	dev_dbg(&port->dev, "Entering...%s\n", __func__);
925 
926 	data = urb->transfer_buffer;
927 
928 	if (urb->actual_length) {
929 		tty_insert_flip_string(&port->port, data, urb->actual_length);
930 		tty_flip_buffer_push(&port->port);
931 	}
932 
933 	if (port->read_urb->status != -EINPROGRESS) {
934 		retval = usb_submit_urb(port->read_urb, GFP_ATOMIC);
935 		if (retval)
936 			dev_dbg(&port->dev, "usb_submit_urb(read bulk) failed, retval = %d\n", retval);
937 	}
938 }
939 
940 /*
941  * mos7720_bulk_out_data_callback
942  *	this is the callback function for when we have finished sending serial
943  *	data on the bulk out endpoint.
944  */
945 static void mos7720_bulk_out_data_callback(struct urb *urb)
946 {
947 	struct moschip_port *mos7720_port;
948 	int status = urb->status;
949 
950 	if (status) {
951 		dev_dbg(&urb->dev->dev, "nonzero write bulk status received:%d\n", status);
952 		return;
953 	}
954 
955 	mos7720_port = urb->context;
956 	if (!mos7720_port) {
957 		dev_dbg(&urb->dev->dev, "NULL mos7720_port pointer\n");
958 		return ;
959 	}
960 
961 	if (mos7720_port->open)
962 		tty_port_tty_wakeup(&mos7720_port->port->port);
963 }
964 
965 /*
966  * mos77xx_probe
967  *	this function installs the appropriate read interrupt endpoint callback
968  *	depending on whether the device is a 7720 or 7715, thus avoiding costly
969  *	run-time checks in the high-frequency callback routine itself.
970  */
971 static int mos77xx_probe(struct usb_serial *serial,
972 			 const struct usb_device_id *id)
973 {
974 	if (id->idProduct == MOSCHIP_DEVICE_ID_7715)
975 		moschip7720_2port_driver.read_int_callback =
976 			mos7715_interrupt_callback;
977 	else
978 		moschip7720_2port_driver.read_int_callback =
979 			mos7720_interrupt_callback;
980 
981 	return 0;
982 }
983 
984 static int mos77xx_calc_num_ports(struct usb_serial *serial)
985 {
986 	u16 product = le16_to_cpu(serial->dev->descriptor.idProduct);
987 	if (product == MOSCHIP_DEVICE_ID_7715)
988 		return 1;
989 
990 	return 2;
991 }
992 
993 static int mos7720_open(struct tty_struct *tty, struct usb_serial_port *port)
994 {
995 	struct usb_serial *serial;
996 	struct urb *urb;
997 	struct moschip_port *mos7720_port;
998 	int response;
999 	int port_number;
1000 	__u8 data;
1001 	int allocated_urbs = 0;
1002 	int j;
1003 
1004 	serial = port->serial;
1005 
1006 	mos7720_port = usb_get_serial_port_data(port);
1007 	if (mos7720_port == NULL)
1008 		return -ENODEV;
1009 
1010 	usb_clear_halt(serial->dev, port->write_urb->pipe);
1011 	usb_clear_halt(serial->dev, port->read_urb->pipe);
1012 
1013 	/* Initialising the write urb pool */
1014 	for (j = 0; j < NUM_URBS; ++j) {
1015 		urb = usb_alloc_urb(0, GFP_KERNEL);
1016 		mos7720_port->write_urb_pool[j] = urb;
1017 		if (!urb)
1018 			continue;
1019 
1020 		urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE,
1021 					       GFP_KERNEL);
1022 		if (!urb->transfer_buffer) {
1023 			usb_free_urb(mos7720_port->write_urb_pool[j]);
1024 			mos7720_port->write_urb_pool[j] = NULL;
1025 			continue;
1026 		}
1027 		allocated_urbs++;
1028 	}
1029 
1030 	if (!allocated_urbs)
1031 		return -ENOMEM;
1032 
1033 	 /* Initialize MCS7720 -- Write Init values to corresponding Registers
1034 	  *
1035 	  * Register Index
1036 	  * 0 : THR/RHR
1037 	  * 1 : IER
1038 	  * 2 : FCR
1039 	  * 3 : LCR
1040 	  * 4 : MCR
1041 	  * 5 : LSR
1042 	  * 6 : MSR
1043 	  * 7 : SPR
1044 	  *
1045 	  * 0x08 : SP1/2 Control Reg
1046 	  */
1047 	port_number = port->port_number;
1048 	read_mos_reg(serial, port_number, LSR, &data);
1049 
1050 	dev_dbg(&port->dev, "SS::%p LSR:%x\n", mos7720_port, data);
1051 
1052 	write_mos_reg(serial, dummy, SP1_REG, 0x02);
1053 	write_mos_reg(serial, dummy, SP2_REG, 0x02);
1054 
1055 	write_mos_reg(serial, port_number, IER, 0x00);
1056 	write_mos_reg(serial, port_number, FCR, 0x00);
1057 
1058 	write_mos_reg(serial, port_number, FCR, 0xcf);
1059 	mos7720_port->shadowLCR = 0x03;
1060 	write_mos_reg(serial, port_number, LCR, mos7720_port->shadowLCR);
1061 	mos7720_port->shadowMCR = 0x0b;
1062 	write_mos_reg(serial, port_number, MCR, mos7720_port->shadowMCR);
1063 
1064 	write_mos_reg(serial, port_number, SP_CONTROL_REG, 0x00);
1065 	read_mos_reg(serial, dummy, SP_CONTROL_REG, &data);
1066 	data = data | (port->port_number + 1);
1067 	write_mos_reg(serial, dummy, SP_CONTROL_REG, data);
1068 	mos7720_port->shadowLCR = 0x83;
1069 	write_mos_reg(serial, port_number, LCR, mos7720_port->shadowLCR);
1070 	write_mos_reg(serial, port_number, THR, 0x0c);
1071 	write_mos_reg(serial, port_number, IER, 0x00);
1072 	mos7720_port->shadowLCR = 0x03;
1073 	write_mos_reg(serial, port_number, LCR, mos7720_port->shadowLCR);
1074 	write_mos_reg(serial, port_number, IER, 0x0c);
1075 
1076 	response = usb_submit_urb(port->read_urb, GFP_KERNEL);
1077 	if (response)
1078 		dev_err(&port->dev, "%s - Error %d submitting read urb\n",
1079 							__func__, response);
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 	write_mos_reg(serial, port->port_number, MCR, 0x00);
1148 	write_mos_reg(serial, port->port_number, IER, 0x00);
1149 
1150 	mos7720_port->open = 0;
1151 }
1152 
1153 static void mos7720_break(struct tty_struct *tty, int break_state)
1154 {
1155 	struct usb_serial_port *port = tty->driver_data;
1156 	unsigned char data;
1157 	struct usb_serial *serial;
1158 	struct moschip_port *mos7720_port;
1159 
1160 	serial = port->serial;
1161 
1162 	mos7720_port = usb_get_serial_port_data(port);
1163 	if (mos7720_port == NULL)
1164 		return;
1165 
1166 	if (break_state == -1)
1167 		data = mos7720_port->shadowLCR | UART_LCR_SBC;
1168 	else
1169 		data = mos7720_port->shadowLCR & ~UART_LCR_SBC;
1170 
1171 	mos7720_port->shadowLCR  = data;
1172 	write_mos_reg(serial, port->port_number, LCR, mos7720_port->shadowLCR);
1173 }
1174 
1175 /*
1176  * mos7720_write_room
1177  *	this function is called by the tty driver when it wants to know how many
1178  *	bytes of data we can accept for a specific port.
1179  *	If successful, we return the amount of room that we have for this port
1180  *	Otherwise we return a negative error number.
1181  */
1182 static int mos7720_write_room(struct tty_struct *tty)
1183 {
1184 	struct usb_serial_port *port = tty->driver_data;
1185 	struct moschip_port *mos7720_port;
1186 	int room = 0;
1187 	int i;
1188 
1189 	mos7720_port = usb_get_serial_port_data(port);
1190 	if (mos7720_port == NULL)
1191 		return -ENODEV;
1192 
1193 	/* FIXME: Locking */
1194 	for (i = 0; i < NUM_URBS; ++i) {
1195 		if (mos7720_port->write_urb_pool[i] &&
1196 		    mos7720_port->write_urb_pool[i]->status != -EINPROGRESS)
1197 			room += URB_TRANSFER_BUFFER_SIZE;
1198 	}
1199 
1200 	dev_dbg(&port->dev, "%s - returns %d\n", __func__, room);
1201 	return room;
1202 }
1203 
1204 static int mos7720_write(struct tty_struct *tty, struct usb_serial_port *port,
1205 				 const unsigned char *data, int count)
1206 {
1207 	int status;
1208 	int i;
1209 	int bytes_sent = 0;
1210 	int transfer_size;
1211 
1212 	struct moschip_port *mos7720_port;
1213 	struct usb_serial *serial;
1214 	struct urb    *urb;
1215 	const unsigned char *current_position = data;
1216 
1217 	serial = port->serial;
1218 
1219 	mos7720_port = usb_get_serial_port_data(port);
1220 	if (mos7720_port == NULL)
1221 		return -ENODEV;
1222 
1223 	/* try to find a free urb in the list */
1224 	urb = NULL;
1225 
1226 	for (i = 0; i < NUM_URBS; ++i) {
1227 		if (mos7720_port->write_urb_pool[i] &&
1228 		    mos7720_port->write_urb_pool[i]->status != -EINPROGRESS) {
1229 			urb = mos7720_port->write_urb_pool[i];
1230 			dev_dbg(&port->dev, "URB:%d\n", i);
1231 			break;
1232 		}
1233 	}
1234 
1235 	if (urb == NULL) {
1236 		dev_dbg(&port->dev, "%s - no more free urbs\n", __func__);
1237 		goto exit;
1238 	}
1239 
1240 	if (urb->transfer_buffer == NULL) {
1241 		urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE,
1242 					       GFP_KERNEL);
1243 		if (!urb->transfer_buffer)
1244 			goto exit;
1245 	}
1246 	transfer_size = min(count, URB_TRANSFER_BUFFER_SIZE);
1247 
1248 	memcpy(urb->transfer_buffer, current_position, transfer_size);
1249 	usb_serial_debug_data(&port->dev, __func__, transfer_size,
1250 			      urb->transfer_buffer);
1251 
1252 	/* fill urb with data and submit  */
1253 	usb_fill_bulk_urb(urb, serial->dev,
1254 			  usb_sndbulkpipe(serial->dev,
1255 					port->bulk_out_endpointAddress),
1256 			  urb->transfer_buffer, transfer_size,
1257 			  mos7720_bulk_out_data_callback, mos7720_port);
1258 
1259 	/* send it down the pipe */
1260 	status = usb_submit_urb(urb, GFP_ATOMIC);
1261 	if (status) {
1262 		dev_err_console(port, "%s - usb_submit_urb(write bulk) failed "
1263 			"with status = %d\n", __func__, status);
1264 		bytes_sent = status;
1265 		goto exit;
1266 	}
1267 	bytes_sent = transfer_size;
1268 
1269 exit:
1270 	return bytes_sent;
1271 }
1272 
1273 static void mos7720_throttle(struct tty_struct *tty)
1274 {
1275 	struct usb_serial_port *port = tty->driver_data;
1276 	struct moschip_port *mos7720_port;
1277 	int status;
1278 
1279 	mos7720_port = usb_get_serial_port_data(port);
1280 
1281 	if (mos7720_port == NULL)
1282 		return;
1283 
1284 	if (!mos7720_port->open) {
1285 		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
1286 		return;
1287 	}
1288 
1289 	/* if we are implementing XON/XOFF, send the stop character */
1290 	if (I_IXOFF(tty)) {
1291 		unsigned char stop_char = STOP_CHAR(tty);
1292 		status = mos7720_write(tty, port, &stop_char, 1);
1293 		if (status <= 0)
1294 			return;
1295 	}
1296 
1297 	/* if we are implementing RTS/CTS, toggle that line */
1298 	if (tty->termios.c_cflag & CRTSCTS) {
1299 		mos7720_port->shadowMCR &= ~UART_MCR_RTS;
1300 		write_mos_reg(port->serial, port->port_number, MCR,
1301 			      mos7720_port->shadowMCR);
1302 	}
1303 }
1304 
1305 static void mos7720_unthrottle(struct tty_struct *tty)
1306 {
1307 	struct usb_serial_port *port = tty->driver_data;
1308 	struct moschip_port *mos7720_port = usb_get_serial_port_data(port);
1309 	int status;
1310 
1311 	if (mos7720_port == NULL)
1312 		return;
1313 
1314 	if (!mos7720_port->open) {
1315 		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
1316 		return;
1317 	}
1318 
1319 	/* if we are implementing XON/XOFF, send the start character */
1320 	if (I_IXOFF(tty)) {
1321 		unsigned char start_char = START_CHAR(tty);
1322 		status = mos7720_write(tty, port, &start_char, 1);
1323 		if (status <= 0)
1324 			return;
1325 	}
1326 
1327 	/* if we are implementing RTS/CTS, toggle that line */
1328 	if (tty->termios.c_cflag & CRTSCTS) {
1329 		mos7720_port->shadowMCR |= UART_MCR_RTS;
1330 		write_mos_reg(port->serial, port->port_number, MCR,
1331 			      mos7720_port->shadowMCR);
1332 	}
1333 }
1334 
1335 /* FIXME: this function does not work */
1336 static int set_higher_rates(struct moschip_port *mos7720_port,
1337 			    unsigned int baud)
1338 {
1339 	struct usb_serial_port *port;
1340 	struct usb_serial *serial;
1341 	int port_number;
1342 	enum mos_regs sp_reg;
1343 	if (mos7720_port == NULL)
1344 		return -EINVAL;
1345 
1346 	port = mos7720_port->port;
1347 	serial = port->serial;
1348 
1349 	 /***********************************************
1350 	 *      Init Sequence for higher rates
1351 	 ***********************************************/
1352 	dev_dbg(&port->dev, "Sending Setting Commands ..........\n");
1353 	port_number = port->port_number;
1354 
1355 	write_mos_reg(serial, port_number, IER, 0x00);
1356 	write_mos_reg(serial, port_number, FCR, 0x00);
1357 	write_mos_reg(serial, port_number, FCR, 0xcf);
1358 	mos7720_port->shadowMCR = 0x0b;
1359 	write_mos_reg(serial, port_number, MCR, mos7720_port->shadowMCR);
1360 	write_mos_reg(serial, dummy, SP_CONTROL_REG, 0x00);
1361 
1362 	/***********************************************
1363 	 *              Set for higher rates           *
1364 	 ***********************************************/
1365 	/* writing baud rate verbatum into uart clock field clearly not right */
1366 	if (port_number == 0)
1367 		sp_reg = SP1_REG;
1368 	else
1369 		sp_reg = SP2_REG;
1370 	write_mos_reg(serial, dummy, sp_reg, baud * 0x10);
1371 	write_mos_reg(serial, dummy, SP_CONTROL_REG, 0x03);
1372 	mos7720_port->shadowMCR = 0x2b;
1373 	write_mos_reg(serial, port_number, MCR, mos7720_port->shadowMCR);
1374 
1375 	/***********************************************
1376 	 *              Set DLL/DLM
1377 	 ***********************************************/
1378 	mos7720_port->shadowLCR = mos7720_port->shadowLCR | UART_LCR_DLAB;
1379 	write_mos_reg(serial, port_number, LCR, mos7720_port->shadowLCR);
1380 	write_mos_reg(serial, port_number, DLL, 0x01);
1381 	write_mos_reg(serial, port_number, DLM, 0x00);
1382 	mos7720_port->shadowLCR = mos7720_port->shadowLCR & ~UART_LCR_DLAB;
1383 	write_mos_reg(serial, port_number, LCR, mos7720_port->shadowLCR);
1384 
1385 	return 0;
1386 }
1387 
1388 /* baud rate information */
1389 struct divisor_table_entry {
1390 	__u32  baudrate;
1391 	__u16  divisor;
1392 };
1393 
1394 /* Define table of divisors for moschip 7720 hardware	   *
1395  * These assume a 3.6864MHz crystal, the standard /16, and *
1396  * MCR.7 = 0.						   */
1397 static struct divisor_table_entry divisor_table[] = {
1398 	{   50,		2304},
1399 	{   110,	1047},	/* 2094.545455 => 230450   => .0217 % over */
1400 	{   134,	857},	/* 1713.011152 => 230398.5 => .00065% under */
1401 	{   150,	768},
1402 	{   300,	384},
1403 	{   600,	192},
1404 	{   1200,	96},
1405 	{   1800,	64},
1406 	{   2400,	48},
1407 	{   4800,	24},
1408 	{   7200,	16},
1409 	{   9600,	12},
1410 	{   19200,	6},
1411 	{   38400,	3},
1412 	{   57600,	2},
1413 	{   115200,	1},
1414 };
1415 
1416 /*****************************************************************************
1417  * calc_baud_rate_divisor
1418  *	this function calculates the proper baud rate divisor for the specified
1419  *	baud rate.
1420  *****************************************************************************/
1421 static int calc_baud_rate_divisor(struct usb_serial_port *port, int baudrate, int *divisor)
1422 {
1423 	int i;
1424 	__u16 custom;
1425 	__u16 round1;
1426 	__u16 round;
1427 
1428 
1429 	dev_dbg(&port->dev, "%s - %d\n", __func__, baudrate);
1430 
1431 	for (i = 0; i < ARRAY_SIZE(divisor_table); i++) {
1432 		if (divisor_table[i].baudrate == baudrate) {
1433 			*divisor = divisor_table[i].divisor;
1434 			return 0;
1435 		}
1436 	}
1437 
1438 	/* After trying for all the standard baud rates    *
1439 	 * Try calculating the divisor for this baud rate  */
1440 	if (baudrate > 75 &&  baudrate < 230400) {
1441 		/* get the divisor */
1442 		custom = (__u16)(230400L  / baudrate);
1443 
1444 		/* Check for round off */
1445 		round1 = (__u16)(2304000L / baudrate);
1446 		round = (__u16)(round1 - (custom * 10));
1447 		if (round > 4)
1448 			custom++;
1449 		*divisor = custom;
1450 
1451 		dev_dbg(&port->dev, "Baud %d = %d\n", baudrate, custom);
1452 		return 0;
1453 	}
1454 
1455 	dev_dbg(&port->dev, "Baud calculation Failed...\n");
1456 	return -EINVAL;
1457 }
1458 
1459 /*
1460  * send_cmd_write_baud_rate
1461  *	this function sends the proper command to change the baud rate of the
1462  *	specified port.
1463  */
1464 static int send_cmd_write_baud_rate(struct moschip_port *mos7720_port,
1465 				    int baudrate)
1466 {
1467 	struct usb_serial_port *port;
1468 	struct usb_serial *serial;
1469 	int divisor;
1470 	int status;
1471 	unsigned char number;
1472 
1473 	if (mos7720_port == NULL)
1474 		return -1;
1475 
1476 	port = mos7720_port->port;
1477 	serial = port->serial;
1478 
1479 	number = port->port_number;
1480 	dev_dbg(&port->dev, "%s - baud = %d\n", __func__, baudrate);
1481 
1482 	/* Calculate the Divisor */
1483 	status = calc_baud_rate_divisor(port, baudrate, &divisor);
1484 	if (status) {
1485 		dev_err(&port->dev, "%s - bad baud rate\n", __func__);
1486 		return status;
1487 	}
1488 
1489 	/* Enable access to divisor latch */
1490 	mos7720_port->shadowLCR = mos7720_port->shadowLCR | UART_LCR_DLAB;
1491 	write_mos_reg(serial, number, LCR, mos7720_port->shadowLCR);
1492 
1493 	/* Write the divisor */
1494 	write_mos_reg(serial, number, DLL, (__u8)(divisor & 0xff));
1495 	write_mos_reg(serial, number, DLM, (__u8)((divisor & 0xff00) >> 8));
1496 
1497 	/* Disable access to divisor latch */
1498 	mos7720_port->shadowLCR = mos7720_port->shadowLCR & ~UART_LCR_DLAB;
1499 	write_mos_reg(serial, number, LCR, mos7720_port->shadowLCR);
1500 
1501 	return status;
1502 }
1503 
1504 /*
1505  * change_port_settings
1506  *	This routine is called to set the UART on the device to match
1507  *      the specified new settings.
1508  */
1509 static void change_port_settings(struct tty_struct *tty,
1510 				 struct moschip_port *mos7720_port,
1511 				 struct ktermios *old_termios)
1512 {
1513 	struct usb_serial_port *port;
1514 	struct usb_serial *serial;
1515 	int baud;
1516 	unsigned cflag;
1517 	unsigned iflag;
1518 	__u8 mask = 0xff;
1519 	__u8 lData;
1520 	__u8 lParity;
1521 	__u8 lStop;
1522 	int status;
1523 	int port_number;
1524 
1525 	if (mos7720_port == NULL)
1526 		return ;
1527 
1528 	port = mos7720_port->port;
1529 	serial = port->serial;
1530 	port_number = port->port_number;
1531 
1532 	if (!mos7720_port->open) {
1533 		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
1534 		return;
1535 	}
1536 
1537 	lData = UART_LCR_WLEN8;
1538 	lStop = 0x00;	/* 1 stop bit */
1539 	lParity = 0x00;	/* No parity */
1540 
1541 	cflag = tty->termios.c_cflag;
1542 	iflag = tty->termios.c_iflag;
1543 
1544 	/* Change the number of bits */
1545 	switch (cflag & CSIZE) {
1546 	case CS5:
1547 		lData = UART_LCR_WLEN5;
1548 		mask = 0x1f;
1549 		break;
1550 
1551 	case CS6:
1552 		lData = UART_LCR_WLEN6;
1553 		mask = 0x3f;
1554 		break;
1555 
1556 	case CS7:
1557 		lData = UART_LCR_WLEN7;
1558 		mask = 0x7f;
1559 		break;
1560 	default:
1561 	case CS8:
1562 		lData = UART_LCR_WLEN8;
1563 		break;
1564 	}
1565 
1566 	/* Change the Parity bit */
1567 	if (cflag & PARENB) {
1568 		if (cflag & PARODD) {
1569 			lParity = UART_LCR_PARITY;
1570 			dev_dbg(&port->dev, "%s - parity = odd\n", __func__);
1571 		} else {
1572 			lParity = (UART_LCR_EPAR | UART_LCR_PARITY);
1573 			dev_dbg(&port->dev, "%s - parity = even\n", __func__);
1574 		}
1575 
1576 	} else {
1577 		dev_dbg(&port->dev, "%s - parity = none\n", __func__);
1578 	}
1579 
1580 	if (cflag & CMSPAR)
1581 		lParity = lParity | 0x20;
1582 
1583 	/* Change the Stop bit */
1584 	if (cflag & CSTOPB) {
1585 		lStop = UART_LCR_STOP;
1586 		dev_dbg(&port->dev, "%s - stop bits = 2\n", __func__);
1587 	} else {
1588 		lStop = 0x00;
1589 		dev_dbg(&port->dev, "%s - stop bits = 1\n", __func__);
1590 	}
1591 
1592 #define LCR_BITS_MASK		0x03	/* Mask for bits/char field */
1593 #define LCR_STOP_MASK		0x04	/* Mask for stop bits field */
1594 #define LCR_PAR_MASK		0x38	/* Mask for parity field */
1595 
1596 	/* Update the LCR with the correct value */
1597 	mos7720_port->shadowLCR &=
1598 		~(LCR_BITS_MASK | LCR_STOP_MASK | LCR_PAR_MASK);
1599 	mos7720_port->shadowLCR |= (lData | lParity | lStop);
1600 
1601 
1602 	/* Disable Interrupts */
1603 	write_mos_reg(serial, port_number, IER, 0x00);
1604 	write_mos_reg(serial, port_number, FCR, 0x00);
1605 	write_mos_reg(serial, port_number, FCR, 0xcf);
1606 
1607 	/* Send the updated LCR value to the mos7720 */
1608 	write_mos_reg(serial, port_number, LCR, mos7720_port->shadowLCR);
1609 	mos7720_port->shadowMCR = 0x0b;
1610 	write_mos_reg(serial, port_number, MCR, mos7720_port->shadowMCR);
1611 
1612 	/* set up the MCR register and send it to the mos7720 */
1613 	mos7720_port->shadowMCR = UART_MCR_OUT2;
1614 	if (cflag & CBAUD)
1615 		mos7720_port->shadowMCR |= (UART_MCR_DTR | UART_MCR_RTS);
1616 
1617 	if (cflag & CRTSCTS) {
1618 		mos7720_port->shadowMCR |= (UART_MCR_XONANY);
1619 		/* To set hardware flow control to the specified *
1620 		 * serial port, in SP1/2_CONTROL_REG             */
1621 		if (port_number)
1622 			write_mos_reg(serial, dummy, SP_CONTROL_REG, 0x01);
1623 		else
1624 			write_mos_reg(serial, dummy, SP_CONTROL_REG, 0x02);
1625 
1626 	} else
1627 		mos7720_port->shadowMCR &= ~(UART_MCR_XONANY);
1628 
1629 	write_mos_reg(serial, port_number, MCR, mos7720_port->shadowMCR);
1630 
1631 	/* Determine divisor based on baud rate */
1632 	baud = tty_get_baud_rate(tty);
1633 	if (!baud) {
1634 		/* pick a default, any default... */
1635 		dev_dbg(&port->dev, "Picked default baud...\n");
1636 		baud = 9600;
1637 	}
1638 
1639 	if (baud >= 230400) {
1640 		set_higher_rates(mos7720_port, baud);
1641 		/* Enable Interrupts */
1642 		write_mos_reg(serial, port_number, IER, 0x0c);
1643 		return;
1644 	}
1645 
1646 	dev_dbg(&port->dev, "%s - baud rate = %d\n", __func__, baud);
1647 	status = send_cmd_write_baud_rate(mos7720_port, baud);
1648 	/* FIXME: needs to write actual resulting baud back not just
1649 	   blindly do so */
1650 	if (cflag & CBAUD)
1651 		tty_encode_baud_rate(tty, baud, baud);
1652 	/* Enable Interrupts */
1653 	write_mos_reg(serial, port_number, IER, 0x0c);
1654 
1655 	if (port->read_urb->status != -EINPROGRESS) {
1656 		status = usb_submit_urb(port->read_urb, GFP_KERNEL);
1657 		if (status)
1658 			dev_dbg(&port->dev, "usb_submit_urb(read bulk) failed, status = %d\n", status);
1659 	}
1660 }
1661 
1662 /*
1663  * mos7720_set_termios
1664  *	this function is called by the tty driver when it wants to change the
1665  *	termios structure.
1666  */
1667 static void mos7720_set_termios(struct tty_struct *tty,
1668 		struct usb_serial_port *port, struct ktermios *old_termios)
1669 {
1670 	int status;
1671 	unsigned int cflag;
1672 	struct usb_serial *serial;
1673 	struct moschip_port *mos7720_port;
1674 
1675 	serial = port->serial;
1676 
1677 	mos7720_port = usb_get_serial_port_data(port);
1678 
1679 	if (mos7720_port == NULL)
1680 		return;
1681 
1682 	if (!mos7720_port->open) {
1683 		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
1684 		return;
1685 	}
1686 
1687 	dev_dbg(&port->dev, "setting termios - ASPIRE\n");
1688 
1689 	cflag = tty->termios.c_cflag;
1690 
1691 	dev_dbg(&port->dev, "%s - cflag %08x iflag %08x\n", __func__,
1692 		tty->termios.c_cflag, RELEVANT_IFLAG(tty->termios.c_iflag));
1693 
1694 	dev_dbg(&port->dev, "%s - old cflag %08x old iflag %08x\n", __func__,
1695 		old_termios->c_cflag, RELEVANT_IFLAG(old_termios->c_iflag));
1696 
1697 	/* change the port settings to the new ones specified */
1698 	change_port_settings(tty, mos7720_port, old_termios);
1699 
1700 	if (port->read_urb->status != -EINPROGRESS) {
1701 		status = usb_submit_urb(port->read_urb, GFP_KERNEL);
1702 		if (status)
1703 			dev_dbg(&port->dev, "usb_submit_urb(read bulk) failed, status = %d\n", status);
1704 	}
1705 }
1706 
1707 /*
1708  * get_lsr_info - get line status register info
1709  *
1710  * Purpose: Let user call ioctl() to get info when the UART physically
1711  * 	    is emptied.  On bus types like RS485, the transmitter must
1712  * 	    release the bus after transmitting. This must be done when
1713  * 	    the transmit shift register is empty, not be done when the
1714  * 	    transmit holding register is empty.  This functionality
1715  * 	    allows an RS485 driver to be written in user space.
1716  */
1717 static int get_lsr_info(struct tty_struct *tty,
1718 		struct moschip_port *mos7720_port, unsigned int __user *value)
1719 {
1720 	struct usb_serial_port *port = tty->driver_data;
1721 	unsigned int result = 0;
1722 	unsigned char data = 0;
1723 	int port_number = port->port_number;
1724 	int count;
1725 
1726 	count = mos7720_chars_in_buffer(tty);
1727 	if (count == 0) {
1728 		read_mos_reg(port->serial, port_number, LSR, &data);
1729 		if ((data & (UART_LSR_TEMT | UART_LSR_THRE))
1730 					== (UART_LSR_TEMT | UART_LSR_THRE)) {
1731 			dev_dbg(&port->dev, "%s -- Empty\n", __func__);
1732 			result = TIOCSER_TEMT;
1733 		}
1734 	}
1735 	if (copy_to_user(value, &result, sizeof(int)))
1736 		return -EFAULT;
1737 	return 0;
1738 }
1739 
1740 static int mos7720_tiocmget(struct tty_struct *tty)
1741 {
1742 	struct usb_serial_port *port = tty->driver_data;
1743 	struct moschip_port *mos7720_port = usb_get_serial_port_data(port);
1744 	unsigned int result = 0;
1745 	unsigned int mcr ;
1746 	unsigned int msr ;
1747 
1748 	mcr = mos7720_port->shadowMCR;
1749 	msr = mos7720_port->shadowMSR;
1750 
1751 	result = ((mcr & UART_MCR_DTR)  ? TIOCM_DTR : 0)   /* 0x002 */
1752 	  | ((mcr & UART_MCR_RTS)   ? TIOCM_RTS : 0)   /* 0x004 */
1753 	  | ((msr & UART_MSR_CTS)   ? TIOCM_CTS : 0)   /* 0x020 */
1754 	  | ((msr & UART_MSR_DCD)   ? TIOCM_CAR : 0)   /* 0x040 */
1755 	  | ((msr & UART_MSR_RI)    ? TIOCM_RI :  0)   /* 0x080 */
1756 	  | ((msr & UART_MSR_DSR)   ? TIOCM_DSR : 0);  /* 0x100 */
1757 
1758 	return result;
1759 }
1760 
1761 static int mos7720_tiocmset(struct tty_struct *tty,
1762 			    unsigned int set, unsigned int clear)
1763 {
1764 	struct usb_serial_port *port = tty->driver_data;
1765 	struct moschip_port *mos7720_port = usb_get_serial_port_data(port);
1766 	unsigned int mcr ;
1767 
1768 	mcr = mos7720_port->shadowMCR;
1769 
1770 	if (set & TIOCM_RTS)
1771 		mcr |= UART_MCR_RTS;
1772 	if (set & TIOCM_DTR)
1773 		mcr |= UART_MCR_DTR;
1774 	if (set & TIOCM_LOOP)
1775 		mcr |= UART_MCR_LOOP;
1776 
1777 	if (clear & TIOCM_RTS)
1778 		mcr &= ~UART_MCR_RTS;
1779 	if (clear & TIOCM_DTR)
1780 		mcr &= ~UART_MCR_DTR;
1781 	if (clear & TIOCM_LOOP)
1782 		mcr &= ~UART_MCR_LOOP;
1783 
1784 	mos7720_port->shadowMCR = mcr;
1785 	write_mos_reg(port->serial, port->port_number, MCR,
1786 		      mos7720_port->shadowMCR);
1787 
1788 	return 0;
1789 }
1790 
1791 static int set_modem_info(struct moschip_port *mos7720_port, unsigned int cmd,
1792 			  unsigned int __user *value)
1793 {
1794 	unsigned int mcr;
1795 	unsigned int arg;
1796 
1797 	struct usb_serial_port *port;
1798 
1799 	if (mos7720_port == NULL)
1800 		return -1;
1801 
1802 	port = (struct usb_serial_port *)mos7720_port->port;
1803 	mcr = mos7720_port->shadowMCR;
1804 
1805 	if (copy_from_user(&arg, value, sizeof(int)))
1806 		return -EFAULT;
1807 
1808 	switch (cmd) {
1809 	case TIOCMBIS:
1810 		if (arg & TIOCM_RTS)
1811 			mcr |= UART_MCR_RTS;
1812 		if (arg & TIOCM_DTR)
1813 			mcr |= UART_MCR_RTS;
1814 		if (arg & TIOCM_LOOP)
1815 			mcr |= UART_MCR_LOOP;
1816 		break;
1817 
1818 	case TIOCMBIC:
1819 		if (arg & TIOCM_RTS)
1820 			mcr &= ~UART_MCR_RTS;
1821 		if (arg & TIOCM_DTR)
1822 			mcr &= ~UART_MCR_RTS;
1823 		if (arg & TIOCM_LOOP)
1824 			mcr &= ~UART_MCR_LOOP;
1825 		break;
1826 
1827 	}
1828 
1829 	mos7720_port->shadowMCR = mcr;
1830 	write_mos_reg(port->serial, port->port_number, MCR,
1831 		      mos7720_port->shadowMCR);
1832 
1833 	return 0;
1834 }
1835 
1836 static int get_serial_info(struct moschip_port *mos7720_port,
1837 			   struct serial_struct __user *retinfo)
1838 {
1839 	struct serial_struct tmp;
1840 
1841 	if (!retinfo)
1842 		return -EFAULT;
1843 
1844 	memset(&tmp, 0, sizeof(tmp));
1845 
1846 	tmp.type		= PORT_16550A;
1847 	tmp.line		= mos7720_port->port->minor;
1848 	tmp.port		= mos7720_port->port->port_number;
1849 	tmp.irq			= 0;
1850 	tmp.flags		= ASYNC_SKIP_TEST | ASYNC_AUTO_IRQ;
1851 	tmp.xmit_fifo_size	= NUM_URBS * URB_TRANSFER_BUFFER_SIZE;
1852 	tmp.baud_base		= 9600;
1853 	tmp.close_delay		= 5*HZ;
1854 	tmp.closing_wait	= 30*HZ;
1855 
1856 	if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
1857 		return -EFAULT;
1858 	return 0;
1859 }
1860 
1861 static int mos7720_ioctl(struct tty_struct *tty,
1862 			 unsigned int cmd, unsigned long arg)
1863 {
1864 	struct usb_serial_port *port = tty->driver_data;
1865 	struct moschip_port *mos7720_port;
1866 
1867 	mos7720_port = usb_get_serial_port_data(port);
1868 	if (mos7720_port == NULL)
1869 		return -ENODEV;
1870 
1871 	switch (cmd) {
1872 	case TIOCSERGETLSR:
1873 		dev_dbg(&port->dev, "%s TIOCSERGETLSR\n", __func__);
1874 		return get_lsr_info(tty, mos7720_port,
1875 					(unsigned int __user *)arg);
1876 
1877 	/* FIXME: These should be using the mode methods */
1878 	case TIOCMBIS:
1879 	case TIOCMBIC:
1880 		dev_dbg(&port->dev, "%s TIOCMSET/TIOCMBIC/TIOCMSET\n", __func__);
1881 		return set_modem_info(mos7720_port, cmd,
1882 				      (unsigned int __user *)arg);
1883 
1884 	case TIOCGSERIAL:
1885 		dev_dbg(&port->dev, "%s TIOCGSERIAL\n", __func__);
1886 		return get_serial_info(mos7720_port,
1887 				       (struct serial_struct __user *)arg);
1888 	}
1889 
1890 	return -ENOIOCTLCMD;
1891 }
1892 
1893 static int mos7720_startup(struct usb_serial *serial)
1894 {
1895 	struct usb_device *dev;
1896 	char data;
1897 	u16 product;
1898 	int ret_val;
1899 
1900 	product = le16_to_cpu(serial->dev->descriptor.idProduct);
1901 	dev = serial->dev;
1902 
1903 	/*
1904 	 * The 7715 uses the first bulk in/out endpoint pair for the parallel
1905 	 * port, and the second for the serial port.  Because the usbserial core
1906 	 * assumes both pairs are serial ports, we must engage in a bit of
1907 	 * subterfuge and swap the pointers for ports 0 and 1 in order to make
1908 	 * port 0 point to the serial port.  However, both moschip devices use a
1909 	 * single interrupt-in endpoint for both ports (as mentioned a little
1910 	 * further down), and this endpoint was assigned to port 0.  So after
1911 	 * the swap, we must copy the interrupt endpoint elements from port 1
1912 	 * (as newly assigned) to port 0, and null out port 1 pointers.
1913 	 */
1914 	if (product == MOSCHIP_DEVICE_ID_7715) {
1915 		struct usb_serial_port *tmp = serial->port[0];
1916 		serial->port[0] = serial->port[1];
1917 		serial->port[1] = tmp;
1918 		serial->port[0]->interrupt_in_urb = tmp->interrupt_in_urb;
1919 		serial->port[0]->interrupt_in_buffer = tmp->interrupt_in_buffer;
1920 		serial->port[0]->interrupt_in_endpointAddress =
1921 			tmp->interrupt_in_endpointAddress;
1922 		serial->port[1]->interrupt_in_urb = NULL;
1923 		serial->port[1]->interrupt_in_buffer = NULL;
1924 	}
1925 
1926 	/* setting configuration feature to one */
1927 	usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
1928 			(__u8)0x03, 0x00, 0x01, 0x00, NULL, 0x00, 5000);
1929 
1930 	/* start the interrupt urb */
1931 	ret_val = usb_submit_urb(serial->port[0]->interrupt_in_urb, GFP_KERNEL);
1932 	if (ret_val)
1933 		dev_err(&dev->dev,
1934 			"%s - Error %d submitting control urb\n",
1935 			__func__, ret_val);
1936 
1937 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
1938 	if (product == MOSCHIP_DEVICE_ID_7715) {
1939 		ret_val = mos7715_parport_init(serial);
1940 		if (ret_val < 0)
1941 			return ret_val;
1942 	}
1943 #endif
1944 	/* LSR For Port 1 */
1945 	read_mos_reg(serial, 0, LSR, &data);
1946 	dev_dbg(&dev->dev, "LSR:%x\n", data);
1947 
1948 	return 0;
1949 }
1950 
1951 static void mos7720_release(struct usb_serial *serial)
1952 {
1953 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
1954 	/* close the parallel port */
1955 
1956 	if (le16_to_cpu(serial->dev->descriptor.idProduct)
1957 	    == MOSCHIP_DEVICE_ID_7715) {
1958 		struct urbtracker *urbtrack;
1959 		unsigned long flags;
1960 		struct mos7715_parport *mos_parport =
1961 			usb_get_serial_data(serial);
1962 
1963 		/* prevent NULL ptr dereference in port callbacks */
1964 		spin_lock(&release_lock);
1965 		mos_parport->pp->private_data = NULL;
1966 		spin_unlock(&release_lock);
1967 
1968 		/* wait for synchronous usb calls to return */
1969 		if (mos_parport->msg_pending)
1970 			wait_for_completion_timeout(&mos_parport->syncmsg_compl,
1971 					    msecs_to_jiffies(MOS_WDR_TIMEOUT));
1972 
1973 		parport_remove_port(mos_parport->pp);
1974 		usb_set_serial_data(serial, NULL);
1975 		mos_parport->serial = NULL;
1976 
1977 		/* if tasklet currently scheduled, wait for it to complete */
1978 		tasklet_kill(&mos_parport->urb_tasklet);
1979 
1980 		/* unlink any urbs sent by the tasklet  */
1981 		spin_lock_irqsave(&mos_parport->listlock, flags);
1982 		list_for_each_entry(urbtrack,
1983 				    &mos_parport->active_urbs,
1984 				    urblist_entry)
1985 			usb_unlink_urb(urbtrack->urb);
1986 		spin_unlock_irqrestore(&mos_parport->listlock, flags);
1987 
1988 		kref_put(&mos_parport->ref_count, destroy_mos_parport);
1989 	}
1990 #endif
1991 }
1992 
1993 static int mos7720_port_probe(struct usb_serial_port *port)
1994 {
1995 	struct moschip_port *mos7720_port;
1996 
1997 	mos7720_port = kzalloc(sizeof(*mos7720_port), GFP_KERNEL);
1998 	if (!mos7720_port)
1999 		return -ENOMEM;
2000 
2001 	/* Initialize all port interrupt end point to port 0 int endpoint.
2002 	 * Our device has only one interrupt endpoint common to all ports.
2003 	 */
2004 	port->interrupt_in_endpointAddress =
2005 		port->serial->port[0]->interrupt_in_endpointAddress;
2006 	mos7720_port->port = port;
2007 
2008 	usb_set_serial_port_data(port, mos7720_port);
2009 
2010 	return 0;
2011 }
2012 
2013 static int mos7720_port_remove(struct usb_serial_port *port)
2014 {
2015 	struct moschip_port *mos7720_port;
2016 
2017 	mos7720_port = usb_get_serial_port_data(port);
2018 	kfree(mos7720_port);
2019 
2020 	return 0;
2021 }
2022 
2023 static struct usb_serial_driver moschip7720_2port_driver = {
2024 	.driver = {
2025 		.owner =	THIS_MODULE,
2026 		.name =		"moschip7720",
2027 	},
2028 	.description		= "Moschip 2 port adapter",
2029 	.id_table		= id_table,
2030 	.calc_num_ports		= mos77xx_calc_num_ports,
2031 	.open			= mos7720_open,
2032 	.close			= mos7720_close,
2033 	.throttle		= mos7720_throttle,
2034 	.unthrottle		= mos7720_unthrottle,
2035 	.probe			= mos77xx_probe,
2036 	.attach			= mos7720_startup,
2037 	.release		= mos7720_release,
2038 	.port_probe		= mos7720_port_probe,
2039 	.port_remove		= mos7720_port_remove,
2040 	.ioctl			= mos7720_ioctl,
2041 	.tiocmget		= mos7720_tiocmget,
2042 	.tiocmset		= mos7720_tiocmset,
2043 	.set_termios		= mos7720_set_termios,
2044 	.write			= mos7720_write,
2045 	.write_room		= mos7720_write_room,
2046 	.chars_in_buffer	= mos7720_chars_in_buffer,
2047 	.break_ctl		= mos7720_break,
2048 	.read_bulk_callback	= mos7720_bulk_in_callback,
2049 	.read_int_callback	= NULL  /* dynamically assigned in probe() */
2050 };
2051 
2052 static struct usb_serial_driver * const serial_drivers[] = {
2053 	&moschip7720_2port_driver, NULL
2054 };
2055 
2056 module_usb_serial_driver(serial_drivers, id_table);
2057 
2058 MODULE_AUTHOR(DRIVER_AUTHOR);
2059 MODULE_DESCRIPTION(DRIVER_DESC);
2060 MODULE_LICENSE("GPL");
2061