xref: /openbmc/linux/drivers/usb/serial/mos7720.c (revision 05bcf503)
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 /*
40  * Version Information
41  */
42 #define DRIVER_VERSION "2.1"
43 #define DRIVER_AUTHOR "Aspire Communications pvt Ltd."
44 #define DRIVER_DESC "Moschip USB Serial Driver"
45 
46 /* default urb timeout */
47 #define MOS_WDR_TIMEOUT	(HZ * 5)
48 
49 #define MOS_MAX_PORT	0x02
50 #define MOS_WRITE	0x0E
51 #define MOS_READ	0x0D
52 
53 /* Interrupt Rotinue Defines	*/
54 #define SERIAL_IIR_RLS	0x06
55 #define SERIAL_IIR_RDA	0x04
56 #define SERIAL_IIR_CTI	0x0c
57 #define SERIAL_IIR_THR	0x02
58 #define SERIAL_IIR_MS	0x00
59 
60 #define NUM_URBS			16	/* URB Count */
61 #define URB_TRANSFER_BUFFER_SIZE	32	/* URB Size */
62 
63 /* This structure holds all of the local serial port information */
64 struct moschip_port {
65 	__u8	shadowLCR;		/* last LCR value received */
66 	__u8	shadowMCR;		/* last MCR value received */
67 	__u8	shadowMSR;		/* last MSR value received */
68 	char			open;
69 	struct async_icount	icount;
70 	struct usb_serial_port	*port;	/* loop back to the owner */
71 	struct urb		*write_urb_pool[NUM_URBS];
72 };
73 
74 static struct usb_serial_driver moschip7720_2port_driver;
75 
76 #define USB_VENDOR_ID_MOSCHIP		0x9710
77 #define MOSCHIP_DEVICE_ID_7720		0x7720
78 #define MOSCHIP_DEVICE_ID_7715		0x7715
79 
80 static const struct usb_device_id id_table[] = {
81 	{ USB_DEVICE(USB_VENDOR_ID_MOSCHIP, MOSCHIP_DEVICE_ID_7720) },
82 	{ USB_DEVICE(USB_VENDOR_ID_MOSCHIP, MOSCHIP_DEVICE_ID_7715) },
83 	{ } /* terminating entry */
84 };
85 MODULE_DEVICE_TABLE(usb, id_table);
86 
87 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
88 
89 /* initial values for parport regs */
90 #define DCR_INIT_VAL       0x0c	/* SLCTIN, nINIT */
91 #define ECR_INIT_VAL       0x00	/* SPP mode */
92 
93 struct urbtracker {
94 	struct mos7715_parport  *mos_parport;
95 	struct list_head        urblist_entry;
96 	struct kref             ref_count;
97 	struct urb              *urb;
98 };
99 
100 enum mos7715_pp_modes {
101 	SPP = 0<<5,
102 	PS2 = 1<<5,      /* moschip calls this 'NIBBLE' mode */
103 	PPF = 2<<5,	 /* moschip calls this 'CB-FIFO mode */
104 };
105 
106 struct mos7715_parport {
107 	struct parport          *pp;	       /* back to containing struct */
108 	struct kref             ref_count;     /* to instance of this struct */
109 	struct list_head        deferred_urbs; /* list deferred async urbs */
110 	struct list_head        active_urbs;   /* list async urbs in flight */
111 	spinlock_t              listlock;      /* protects list access */
112 	bool                    msg_pending;   /* usb sync call pending */
113 	struct completion       syncmsg_compl; /* usb sync call completed */
114 	struct tasklet_struct   urb_tasklet;   /* for sending deferred urbs */
115 	struct usb_serial       *serial;       /* back to containing struct */
116 	__u8	                shadowECR;     /* parallel port regs... */
117 	__u8	                shadowDCR;
118 	atomic_t                shadowDSR;     /* updated in int-in callback */
119 };
120 
121 /* lock guards against dereferencing NULL ptr in parport ops callbacks */
122 static DEFINE_SPINLOCK(release_lock);
123 
124 #endif	/* CONFIG_USB_SERIAL_MOS7715_PARPORT */
125 
126 static const unsigned int dummy; /* for clarity in register access fns */
127 
128 enum mos_regs {
129 	THR,	          /* serial port regs */
130 	RHR,
131 	IER,
132 	FCR,
133 	ISR,
134 	LCR,
135 	MCR,
136 	LSR,
137 	MSR,
138 	SPR,
139 	DLL,
140 	DLM,
141 	DPR,              /* parallel port regs */
142 	DSR,
143 	DCR,
144 	ECR,
145 	SP1_REG,          /* device control regs */
146 	SP2_REG,          /* serial port 2 (7720 only) */
147 	PP_REG,
148 	SP_CONTROL_REG,
149 };
150 
151 /*
152  * Return the correct value for the Windex field of the setup packet
153  * for a control endpoint message.  See the 7715 datasheet.
154  */
155 static inline __u16 get_reg_index(enum mos_regs reg)
156 {
157 	static const __u16 mos7715_index_lookup_table[] = {
158 		0x00,		/* THR */
159 		0x00,		/* RHR */
160 		0x01,		/* IER */
161 		0x02,		/* FCR */
162 		0x02,		/* ISR */
163 		0x03,		/* LCR */
164 		0x04,		/* MCR */
165 		0x05,		/* LSR */
166 		0x06,		/* MSR */
167 		0x07,		/* SPR */
168 		0x00,		/* DLL */
169 		0x01,		/* DLM */
170 		0x00,		/* DPR */
171 		0x01,		/* DSR */
172 		0x02,		/* DCR */
173 		0x0a,		/* ECR */
174 		0x01,		/* SP1_REG */
175 		0x02,		/* SP2_REG (7720 only) */
176 		0x04,		/* PP_REG (7715 only) */
177 		0x08,		/* SP_CONTROL_REG */
178 	};
179 	return mos7715_index_lookup_table[reg];
180 }
181 
182 /*
183  * Return the correct value for the upper byte of the Wvalue field of
184  * the setup packet for a control endpoint message.
185  */
186 static inline __u16 get_reg_value(enum mos_regs reg,
187 				  unsigned int serial_portnum)
188 {
189 	if (reg >= SP1_REG)	      /* control reg */
190 		return 0x0000;
191 
192 	else if (reg >= DPR)	      /* parallel port reg (7715 only) */
193 		return 0x0100;
194 
195 	else			      /* serial port reg */
196 		return (serial_portnum + 2) << 8;
197 }
198 
199 /*
200  * Write data byte to the specified device register.  The data is embedded in
201  * the value field of the setup packet. serial_portnum is ignored for registers
202  * not specific to a particular serial port.
203  */
204 static int write_mos_reg(struct usb_serial *serial, unsigned int serial_portnum,
205 			 enum mos_regs reg, __u8 data)
206 {
207 	struct usb_device *usbdev = serial->dev;
208 	unsigned int pipe = usb_sndctrlpipe(usbdev, 0);
209 	__u8 request = (__u8)0x0e;
210 	__u8 requesttype = (__u8)0x40;
211 	__u16 index = get_reg_index(reg);
212 	__u16 value = get_reg_value(reg, serial_portnum) + data;
213 	int status = usb_control_msg(usbdev, pipe, request, requesttype, value,
214 				     index, NULL, 0, MOS_WDR_TIMEOUT);
215 	if (status < 0)
216 		dev_err(&usbdev->dev,
217 			"mos7720: usb_control_msg() failed: %d", status);
218 	return status;
219 }
220 
221 /*
222  * Read data byte from the specified device register.  The data returned by the
223  * device is embedded in the value field of the setup packet.  serial_portnum is
224  * ignored for registers that are not specific to a particular serial port.
225  */
226 static int read_mos_reg(struct usb_serial *serial, unsigned int serial_portnum,
227 			enum mos_regs reg, __u8 *data)
228 {
229 	struct usb_device *usbdev = serial->dev;
230 	unsigned int pipe = usb_rcvctrlpipe(usbdev, 0);
231 	__u8 request = (__u8)0x0d;
232 	__u8 requesttype = (__u8)0xc0;
233 	__u16 index = get_reg_index(reg);
234 	__u16 value = get_reg_value(reg, serial_portnum);
235 	int status = usb_control_msg(usbdev, pipe, request, requesttype, value,
236 				     index, data, 1, MOS_WDR_TIMEOUT);
237 	if (status < 0)
238 		dev_err(&usbdev->dev,
239 			"mos7720: usb_control_msg() failed: %d", status);
240 	return status;
241 }
242 
243 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
244 
245 static inline int mos7715_change_mode(struct mos7715_parport *mos_parport,
246 				      enum mos7715_pp_modes mode)
247 {
248 	mos_parport->shadowECR = mode;
249 	write_mos_reg(mos_parport->serial, dummy, ECR, mos_parport->shadowECR);
250 	return 0;
251 }
252 
253 static void destroy_mos_parport(struct kref *kref)
254 {
255 	struct mos7715_parport *mos_parport =
256 		container_of(kref, struct mos7715_parport, ref_count);
257 
258 	kfree(mos_parport);
259 }
260 
261 static void destroy_urbtracker(struct kref *kref)
262 {
263 	struct urbtracker *urbtrack =
264 		container_of(kref, struct urbtracker, ref_count);
265 	struct mos7715_parport *mos_parport = urbtrack->mos_parport;
266 
267 	usb_free_urb(urbtrack->urb);
268 	kfree(urbtrack);
269 	kref_put(&mos_parport->ref_count, destroy_mos_parport);
270 }
271 
272 /*
273  * This runs as a tasklet when sending an urb in a non-blocking parallel
274  * port callback had to be deferred because the disconnect mutex could not be
275  * obtained at the time.
276  */
277 static void send_deferred_urbs(unsigned long _mos_parport)
278 {
279 	int ret_val;
280 	unsigned long flags;
281 	struct mos7715_parport *mos_parport = (void *)_mos_parport;
282 	struct urbtracker *urbtrack, *tmp;
283 	struct list_head *cursor, *next;
284 	struct device *dev;
285 
286 	/* if release function ran, game over */
287 	if (unlikely(mos_parport->serial == NULL))
288 		return;
289 
290 	dev = &mos_parport->serial->dev->dev;
291 
292 	/* try again to get the mutex */
293 	if (!mutex_trylock(&mos_parport->serial->disc_mutex)) {
294 		dev_dbg(dev, "%s: rescheduling tasklet\n", __func__);
295 		tasklet_schedule(&mos_parport->urb_tasklet);
296 		return;
297 	}
298 
299 	/* if device disconnected, game over */
300 	if (unlikely(mos_parport->serial->disconnected)) {
301 		mutex_unlock(&mos_parport->serial->disc_mutex);
302 		return;
303 	}
304 
305 	spin_lock_irqsave(&mos_parport->listlock, flags);
306 	if (list_empty(&mos_parport->deferred_urbs)) {
307 		spin_unlock_irqrestore(&mos_parport->listlock, flags);
308 		mutex_unlock(&mos_parport->serial->disc_mutex);
309 		dev_dbg(dev, "%s: deferred_urbs list empty\n", __func__);
310 		return;
311 	}
312 
313 	/* move contents of deferred_urbs list to active_urbs list and submit */
314 	list_for_each_safe(cursor, next, &mos_parport->deferred_urbs)
315 		list_move_tail(cursor, &mos_parport->active_urbs);
316 	list_for_each_entry_safe(urbtrack, tmp, &mos_parport->active_urbs,
317 			    urblist_entry) {
318 		ret_val = usb_submit_urb(urbtrack->urb, GFP_ATOMIC);
319 		dev_dbg(dev, "%s: urb submitted\n", __func__);
320 		if (ret_val) {
321 			dev_err(dev, "usb_submit_urb() failed: %d\n", ret_val);
322 			list_del(&urbtrack->urblist_entry);
323 			kref_put(&urbtrack->ref_count, destroy_urbtracker);
324 		}
325 	}
326 	spin_unlock_irqrestore(&mos_parport->listlock, flags);
327 	mutex_unlock(&mos_parport->serial->disc_mutex);
328 }
329 
330 /* callback for parallel port control urbs submitted asynchronously */
331 static void async_complete(struct urb *urb)
332 {
333 	struct urbtracker *urbtrack = urb->context;
334 	int status = urb->status;
335 
336 	if (unlikely(status))
337 		dev_dbg(&urb->dev->dev, "%s - nonzero urb status received: %d\n", __func__, status);
338 
339 	/* remove the urbtracker from the active_urbs list */
340 	spin_lock(&urbtrack->mos_parport->listlock);
341 	list_del(&urbtrack->urblist_entry);
342 	spin_unlock(&urbtrack->mos_parport->listlock);
343 	kref_put(&urbtrack->ref_count, destroy_urbtracker);
344 }
345 
346 static int write_parport_reg_nonblock(struct mos7715_parport *mos_parport,
347 				      enum mos_regs reg, __u8 data)
348 {
349 	struct urbtracker *urbtrack;
350 	int ret_val;
351 	unsigned long flags;
352 	struct usb_ctrlrequest setup;
353 	struct usb_serial *serial = mos_parport->serial;
354 	struct usb_device *usbdev = serial->dev;
355 
356 	/* create and initialize the control urb and containing urbtracker */
357 	urbtrack = kmalloc(sizeof(struct urbtracker), GFP_ATOMIC);
358 	if (urbtrack == NULL) {
359 		dev_err(&usbdev->dev, "out of memory");
360 		return -ENOMEM;
361 	}
362 	kref_get(&mos_parport->ref_count);
363 	urbtrack->mos_parport = mos_parport;
364 	urbtrack->urb = usb_alloc_urb(0, GFP_ATOMIC);
365 	if (urbtrack->urb == NULL) {
366 		dev_err(&usbdev->dev, "out of urbs");
367 		kfree(urbtrack);
368 		return -ENOMEM;
369 	}
370 	setup.bRequestType = (__u8)0x40;
371 	setup.bRequest = (__u8)0x0e;
372 	setup.wValue = get_reg_value(reg, dummy);
373 	setup.wIndex = get_reg_index(reg);
374 	setup.wLength = 0;
375 	usb_fill_control_urb(urbtrack->urb, usbdev,
376 			     usb_sndctrlpipe(usbdev, 0),
377 			     (unsigned char *)&setup,
378 			     NULL, 0, async_complete, urbtrack);
379 	kref_init(&urbtrack->ref_count);
380 	INIT_LIST_HEAD(&urbtrack->urblist_entry);
381 
382 	/*
383 	 * get the disconnect mutex, or add tracker to the deferred_urbs list
384 	 * and schedule a tasklet to try again later
385 	 */
386 	if (!mutex_trylock(&serial->disc_mutex)) {
387 		spin_lock_irqsave(&mos_parport->listlock, flags);
388 		list_add_tail(&urbtrack->urblist_entry,
389 			      &mos_parport->deferred_urbs);
390 		spin_unlock_irqrestore(&mos_parport->listlock, flags);
391 		tasklet_schedule(&mos_parport->urb_tasklet);
392 		dev_dbg(&usbdev->dev, "tasklet scheduled");
393 		return 0;
394 	}
395 
396 	/* bail if device disconnected */
397 	if (serial->disconnected) {
398 		kref_put(&urbtrack->ref_count, destroy_urbtracker);
399 		mutex_unlock(&serial->disc_mutex);
400 		return -ENODEV;
401 	}
402 
403 	/* add the tracker to the active_urbs list and submit */
404 	spin_lock_irqsave(&mos_parport->listlock, flags);
405 	list_add_tail(&urbtrack->urblist_entry, &mos_parport->active_urbs);
406 	spin_unlock_irqrestore(&mos_parport->listlock, flags);
407 	ret_val = usb_submit_urb(urbtrack->urb, GFP_ATOMIC);
408 	mutex_unlock(&serial->disc_mutex);
409 	if (ret_val) {
410 		dev_err(&usbdev->dev,
411 			"%s: submit_urb() failed: %d", __func__, ret_val);
412 		spin_lock_irqsave(&mos_parport->listlock, flags);
413 		list_del(&urbtrack->urblist_entry);
414 		spin_unlock_irqrestore(&mos_parport->listlock, flags);
415 		kref_put(&urbtrack->ref_count, destroy_urbtracker);
416 		return ret_val;
417 	}
418 	return 0;
419 }
420 
421 /*
422  * This is the the common top part of all parallel port callback operations that
423  * send synchronous messages to the device.  This implements convoluted locking
424  * that avoids two scenarios: (1) a port operation is called after usbserial
425  * has called our release function, at which point struct mos7715_parport has
426  * been destroyed, and (2) the device has been disconnected, but usbserial has
427  * not called the release function yet because someone has a serial port open.
428  * The shared release_lock prevents the first, and the mutex and disconnected
429  * flag maintained by usbserial covers the second.  We also use the msg_pending
430  * flag to ensure that all synchronous usb messgage calls have completed before
431  * our release function can return.
432  */
433 static int parport_prologue(struct parport *pp)
434 {
435 	struct mos7715_parport *mos_parport;
436 
437 	spin_lock(&release_lock);
438 	mos_parport = pp->private_data;
439 	if (unlikely(mos_parport == NULL)) {
440 		/* release fn called, port struct destroyed */
441 		spin_unlock(&release_lock);
442 		return -1;
443 	}
444 	mos_parport->msg_pending = true;   /* synch usb call pending */
445 	INIT_COMPLETION(mos_parport->syncmsg_compl);
446 	spin_unlock(&release_lock);
447 
448 	mutex_lock(&mos_parport->serial->disc_mutex);
449 	if (mos_parport->serial->disconnected) {
450 		/* device disconnected */
451 		mutex_unlock(&mos_parport->serial->disc_mutex);
452 		mos_parport->msg_pending = false;
453 		complete(&mos_parport->syncmsg_compl);
454 		return -1;
455 	}
456 
457 	return 0;
458 }
459 
460 /*
461  * This is the the common bottom part of all parallel port functions that send
462  * synchronous messages to the device.
463  */
464 static inline void parport_epilogue(struct parport *pp)
465 {
466 	struct mos7715_parport *mos_parport = pp->private_data;
467 	mutex_unlock(&mos_parport->serial->disc_mutex);
468 	mos_parport->msg_pending = false;
469 	complete(&mos_parport->syncmsg_compl);
470 }
471 
472 static void parport_mos7715_write_data(struct parport *pp, unsigned char d)
473 {
474 	struct mos7715_parport *mos_parport = pp->private_data;
475 
476 	if (parport_prologue(pp) < 0)
477 		return;
478 	mos7715_change_mode(mos_parport, SPP);
479 	write_mos_reg(mos_parport->serial, dummy, DPR, (__u8)d);
480 	parport_epilogue(pp);
481 }
482 
483 static unsigned char parport_mos7715_read_data(struct parport *pp)
484 {
485 	struct mos7715_parport *mos_parport = pp->private_data;
486 	unsigned char d;
487 
488 	if (parport_prologue(pp) < 0)
489 		return 0;
490 	read_mos_reg(mos_parport->serial, dummy, DPR, &d);
491 	parport_epilogue(pp);
492 	return d;
493 }
494 
495 static void parport_mos7715_write_control(struct parport *pp, unsigned char d)
496 {
497 	struct mos7715_parport *mos_parport = pp->private_data;
498 	__u8 data;
499 
500 	if (parport_prologue(pp) < 0)
501 		return;
502 	data = ((__u8)d & 0x0f) | (mos_parport->shadowDCR & 0xf0);
503 	write_mos_reg(mos_parport->serial, dummy, DCR, data);
504 	mos_parport->shadowDCR = data;
505 	parport_epilogue(pp);
506 }
507 
508 static unsigned char parport_mos7715_read_control(struct parport *pp)
509 {
510 	struct mos7715_parport *mos_parport = pp->private_data;
511 	__u8 dcr;
512 
513 	spin_lock(&release_lock);
514 	mos_parport = pp->private_data;
515 	if (unlikely(mos_parport == NULL)) {
516 		spin_unlock(&release_lock);
517 		return 0;
518 	}
519 	dcr = mos_parport->shadowDCR & 0x0f;
520 	spin_unlock(&release_lock);
521 	return dcr;
522 }
523 
524 static unsigned char parport_mos7715_frob_control(struct parport *pp,
525 						  unsigned char mask,
526 						  unsigned char val)
527 {
528 	struct mos7715_parport *mos_parport = pp->private_data;
529 	__u8 dcr;
530 
531 	mask &= 0x0f;
532 	val &= 0x0f;
533 	if (parport_prologue(pp) < 0)
534 		return 0;
535 	mos_parport->shadowDCR = (mos_parport->shadowDCR & (~mask)) ^ val;
536 	write_mos_reg(mos_parport->serial, dummy, DCR, mos_parport->shadowDCR);
537 	dcr = mos_parport->shadowDCR & 0x0f;
538 	parport_epilogue(pp);
539 	return dcr;
540 }
541 
542 static unsigned char parport_mos7715_read_status(struct parport *pp)
543 {
544 	unsigned char status;
545 	struct mos7715_parport *mos_parport = pp->private_data;
546 
547 	spin_lock(&release_lock);
548 	mos_parport = pp->private_data;
549 	if (unlikely(mos_parport == NULL)) {	/* release called */
550 		spin_unlock(&release_lock);
551 		return 0;
552 	}
553 	status = atomic_read(&mos_parport->shadowDSR) & 0xf8;
554 	spin_unlock(&release_lock);
555 	return status;
556 }
557 
558 static void parport_mos7715_enable_irq(struct parport *pp)
559 {
560 }
561 
562 static void parport_mos7715_disable_irq(struct parport *pp)
563 {
564 }
565 
566 static void parport_mos7715_data_forward(struct parport *pp)
567 {
568 	struct mos7715_parport *mos_parport = pp->private_data;
569 
570 	if (parport_prologue(pp) < 0)
571 		return;
572 	mos7715_change_mode(mos_parport, PS2);
573 	mos_parport->shadowDCR &=  ~0x20;
574 	write_mos_reg(mos_parport->serial, dummy, DCR, mos_parport->shadowDCR);
575 	parport_epilogue(pp);
576 }
577 
578 static void parport_mos7715_data_reverse(struct parport *pp)
579 {
580 	struct mos7715_parport *mos_parport = pp->private_data;
581 
582 	if (parport_prologue(pp) < 0)
583 		return;
584 	mos7715_change_mode(mos_parport, PS2);
585 	mos_parport->shadowDCR |= 0x20;
586 	write_mos_reg(mos_parport->serial, dummy, DCR, mos_parport->shadowDCR);
587 	parport_epilogue(pp);
588 }
589 
590 static void parport_mos7715_init_state(struct pardevice *dev,
591 				       struct parport_state *s)
592 {
593 	s->u.pc.ctr = DCR_INIT_VAL;
594 	s->u.pc.ecr = ECR_INIT_VAL;
595 }
596 
597 /* N.B. Parport core code requires that this function not block */
598 static void parport_mos7715_save_state(struct parport *pp,
599 				       struct parport_state *s)
600 {
601 	struct mos7715_parport *mos_parport;
602 
603 	spin_lock(&release_lock);
604 	mos_parport = pp->private_data;
605 	if (unlikely(mos_parport == NULL)) {	/* release called */
606 		spin_unlock(&release_lock);
607 		return;
608 	}
609 	s->u.pc.ctr = mos_parport->shadowDCR;
610 	s->u.pc.ecr = mos_parport->shadowECR;
611 	spin_unlock(&release_lock);
612 }
613 
614 /* N.B. Parport core code requires that this function not block */
615 static void parport_mos7715_restore_state(struct parport *pp,
616 					  struct parport_state *s)
617 {
618 	struct mos7715_parport *mos_parport;
619 
620 	spin_lock(&release_lock);
621 	mos_parport = pp->private_data;
622 	if (unlikely(mos_parport == NULL)) {	/* release called */
623 		spin_unlock(&release_lock);
624 		return;
625 	}
626 	write_parport_reg_nonblock(mos_parport, DCR, mos_parport->shadowDCR);
627 	write_parport_reg_nonblock(mos_parport, ECR, mos_parport->shadowECR);
628 	spin_unlock(&release_lock);
629 }
630 
631 static size_t parport_mos7715_write_compat(struct parport *pp,
632 					   const void *buffer,
633 					   size_t len, int flags)
634 {
635 	int retval;
636 	struct mos7715_parport *mos_parport = pp->private_data;
637 	int actual_len;
638 
639 	if (parport_prologue(pp) < 0)
640 		return 0;
641 	mos7715_change_mode(mos_parport, PPF);
642 	retval = usb_bulk_msg(mos_parport->serial->dev,
643 			      usb_sndbulkpipe(mos_parport->serial->dev, 2),
644 			      (void *)buffer, len, &actual_len,
645 			      MOS_WDR_TIMEOUT);
646 	parport_epilogue(pp);
647 	if (retval) {
648 		dev_err(&mos_parport->serial->dev->dev,
649 			"mos7720: usb_bulk_msg() failed: %d", retval);
650 		return 0;
651 	}
652 	return actual_len;
653 }
654 
655 static struct parport_operations parport_mos7715_ops = {
656 	.owner =		THIS_MODULE,
657 	.write_data =		parport_mos7715_write_data,
658 	.read_data =		parport_mos7715_read_data,
659 
660 	.write_control =	parport_mos7715_write_control,
661 	.read_control =		parport_mos7715_read_control,
662 	.frob_control =		parport_mos7715_frob_control,
663 
664 	.read_status =		parport_mos7715_read_status,
665 
666 	.enable_irq =		parport_mos7715_enable_irq,
667 	.disable_irq =		parport_mos7715_disable_irq,
668 
669 	.data_forward =		parport_mos7715_data_forward,
670 	.data_reverse =		parport_mos7715_data_reverse,
671 
672 	.init_state =		parport_mos7715_init_state,
673 	.save_state =		parport_mos7715_save_state,
674 	.restore_state =	parport_mos7715_restore_state,
675 
676 	.compat_write_data =	parport_mos7715_write_compat,
677 
678 	.nibble_read_data =	parport_ieee1284_read_nibble,
679 	.byte_read_data =	parport_ieee1284_read_byte,
680 };
681 
682 /*
683  * Allocate and initialize parallel port control struct, initialize
684  * the parallel port hardware device, and register with the parport subsystem.
685  */
686 static int mos7715_parport_init(struct usb_serial *serial)
687 {
688 	struct mos7715_parport *mos_parport;
689 
690 	/* allocate and initialize parallel port control struct */
691 	mos_parport = kzalloc(sizeof(struct mos7715_parport), GFP_KERNEL);
692 	if (mos_parport == NULL) {
693 		dev_dbg(&serial->dev->dev, "%s: kzalloc failed\n", __func__);
694 		return -ENOMEM;
695 	}
696 	mos_parport->msg_pending = false;
697 	kref_init(&mos_parport->ref_count);
698 	spin_lock_init(&mos_parport->listlock);
699 	INIT_LIST_HEAD(&mos_parport->active_urbs);
700 	INIT_LIST_HEAD(&mos_parport->deferred_urbs);
701 	usb_set_serial_data(serial, mos_parport); /* hijack private pointer */
702 	mos_parport->serial = serial;
703 	tasklet_init(&mos_parport->urb_tasklet, send_deferred_urbs,
704 		     (unsigned long) mos_parport);
705 	init_completion(&mos_parport->syncmsg_compl);
706 
707 	/* cycle parallel port reset bit */
708 	write_mos_reg(mos_parport->serial, dummy, PP_REG, (__u8)0x80);
709 	write_mos_reg(mos_parport->serial, dummy, PP_REG, (__u8)0x00);
710 
711 	/* initialize device registers */
712 	mos_parport->shadowDCR = DCR_INIT_VAL;
713 	write_mos_reg(mos_parport->serial, dummy, DCR, mos_parport->shadowDCR);
714 	mos_parport->shadowECR = ECR_INIT_VAL;
715 	write_mos_reg(mos_parport->serial, dummy, ECR, mos_parport->shadowECR);
716 
717 	/* register with parport core */
718 	mos_parport->pp = parport_register_port(0, PARPORT_IRQ_NONE,
719 						PARPORT_DMA_NONE,
720 						&parport_mos7715_ops);
721 	if (mos_parport->pp == NULL) {
722 		dev_err(&serial->interface->dev,
723 			"Could not register parport\n");
724 		kref_put(&mos_parport->ref_count, destroy_mos_parport);
725 		return -EIO;
726 	}
727 	mos_parport->pp->private_data = mos_parport;
728 	mos_parport->pp->modes = PARPORT_MODE_COMPAT | PARPORT_MODE_PCSPP;
729 	mos_parport->pp->dev = &serial->interface->dev;
730 	parport_announce_port(mos_parport->pp);
731 
732 	return 0;
733 }
734 #endif	/* CONFIG_USB_SERIAL_MOS7715_PARPORT */
735 
736 /*
737  * mos7720_interrupt_callback
738  *	this is the callback function for when we have received data on the
739  *	interrupt endpoint.
740  */
741 static void mos7720_interrupt_callback(struct urb *urb)
742 {
743 	int result;
744 	int length;
745 	int status = urb->status;
746 	struct device *dev = &urb->dev->dev;
747 	__u8 *data;
748 	__u8 sp1;
749 	__u8 sp2;
750 
751 	switch (status) {
752 	case 0:
753 		/* success */
754 		break;
755 	case -ECONNRESET:
756 	case -ENOENT:
757 	case -ESHUTDOWN:
758 		/* this urb is terminated, clean up */
759 		dev_dbg(dev, "%s - urb shutting down with status: %d\n", __func__, status);
760 		return;
761 	default:
762 		dev_dbg(dev, "%s - nonzero urb status received: %d\n", __func__, status);
763 		goto exit;
764 	}
765 
766 	length = urb->actual_length;
767 	data = urb->transfer_buffer;
768 
769 	/* Moschip get 4 bytes
770 	 * Byte 1 IIR Port 1 (port.number is 0)
771 	 * Byte 2 IIR Port 2 (port.number is 1)
772 	 * Byte 3 --------------
773 	 * Byte 4 FIFO status for both */
774 
775 	/* the above description is inverted
776 	 * 	oneukum 2007-03-14 */
777 
778 	if (unlikely(length != 4)) {
779 		dev_dbg(dev, "Wrong data !!!\n");
780 		return;
781 	}
782 
783 	sp1 = data[3];
784 	sp2 = data[2];
785 
786 	if ((sp1 | sp2) & 0x01) {
787 		/* No Interrupt Pending in both the ports */
788 		dev_dbg(dev, "No Interrupt !!!\n");
789 	} else {
790 		switch (sp1 & 0x0f) {
791 		case SERIAL_IIR_RLS:
792 			dev_dbg(dev, "Serial Port 1: Receiver status error or address bit detected in 9-bit mode\n");
793 			break;
794 		case SERIAL_IIR_CTI:
795 			dev_dbg(dev, "Serial Port 1: Receiver time out\n");
796 			break;
797 		case SERIAL_IIR_MS:
798 			/* dev_dbg(dev, "Serial Port 1: Modem status change\n"); */
799 			break;
800 		}
801 
802 		switch (sp2 & 0x0f) {
803 		case SERIAL_IIR_RLS:
804 			dev_dbg(dev, "Serial Port 2: Receiver status error or address bit detected in 9-bit mode\n");
805 			break;
806 		case SERIAL_IIR_CTI:
807 			dev_dbg(dev, "Serial Port 2: Receiver time out\n");
808 			break;
809 		case SERIAL_IIR_MS:
810 			/* dev_dbg(dev, "Serial Port 2: Modem status change\n"); */
811 			break;
812 		}
813 	}
814 
815 exit:
816 	result = usb_submit_urb(urb, GFP_ATOMIC);
817 	if (result)
818 		dev_err(dev, "%s - Error %d submitting control urb\n", __func__, result);
819 }
820 
821 /*
822  * mos7715_interrupt_callback
823  *	this is the 7715's callback function for when we have received data on
824  *	the interrupt endpoint.
825  */
826 static void mos7715_interrupt_callback(struct urb *urb)
827 {
828 	int result;
829 	int length;
830 	int status = urb->status;
831 	struct device *dev = &urb->dev->dev;
832 	__u8 *data;
833 	__u8 iir;
834 
835 	switch (status) {
836 	case 0:
837 		/* success */
838 		break;
839 	case -ECONNRESET:
840 	case -ENOENT:
841 	case -ESHUTDOWN:
842 	case -ENODEV:
843 		/* this urb is terminated, clean up */
844 		dev_dbg(dev, "%s - urb shutting down with status: %d\n", __func__, status);
845 		return;
846 	default:
847 		dev_dbg(dev, "%s - nonzero urb status received: %d\n", __func__, status);
848 		goto exit;
849 	}
850 
851 	length = urb->actual_length;
852 	data = urb->transfer_buffer;
853 
854 	/* Structure of data from 7715 device:
855 	 * Byte 1: IIR serial Port
856 	 * Byte 2: unused
857 	 * Byte 2: DSR parallel port
858 	 * Byte 4: FIFO status for both */
859 
860 	if (unlikely(length != 4)) {
861 		dev_dbg(dev, "Wrong data !!!\n");
862 		return;
863 	}
864 
865 	iir = data[0];
866 	if (!(iir & 0x01)) {	/* serial port interrupt pending */
867 		switch (iir & 0x0f) {
868 		case SERIAL_IIR_RLS:
869 			dev_dbg(dev, "Serial Port: Receiver status error or address bit detected in 9-bit mode\n\n");
870 			break;
871 		case SERIAL_IIR_CTI:
872 			dev_dbg(dev, "Serial Port: Receiver time out\n");
873 			break;
874 		case SERIAL_IIR_MS:
875 			/* dev_dbg(dev, "Serial Port: Modem status change\n"); */
876 			break;
877 		}
878 	}
879 
880 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
881 	{       /* update local copy of DSR reg */
882 		struct usb_serial_port *port = urb->context;
883 		struct mos7715_parport *mos_parport = port->serial->private;
884 		if (unlikely(mos_parport == NULL))
885 			return;
886 		atomic_set(&mos_parport->shadowDSR, data[2]);
887 	}
888 #endif
889 
890 exit:
891 	result = usb_submit_urb(urb, GFP_ATOMIC);
892 	if (result)
893 		dev_err(dev, "%s - Error %d submitting control urb\n", __func__, result);
894 }
895 
896 /*
897  * mos7720_bulk_in_callback
898  *	this is the callback function for when we have received data on the
899  *	bulk in endpoint.
900  */
901 static void mos7720_bulk_in_callback(struct urb *urb)
902 {
903 	int retval;
904 	unsigned char *data ;
905 	struct usb_serial_port *port;
906 	struct tty_struct *tty;
907 	int status = urb->status;
908 
909 	if (status) {
910 		dev_dbg(&urb->dev->dev, "nonzero read bulk status received: %d\n", status);
911 		return;
912 	}
913 
914 	port = urb->context;
915 
916 	dev_dbg(&port->dev, "Entering...%s\n", __func__);
917 
918 	data = urb->transfer_buffer;
919 
920 	tty = tty_port_tty_get(&port->port);
921 	if (tty && urb->actual_length) {
922 		tty_insert_flip_string(tty, data, urb->actual_length);
923 		tty_flip_buffer_push(tty);
924 	}
925 	tty_kref_put(tty);
926 
927 	if (port->read_urb->status != -EINPROGRESS) {
928 		retval = usb_submit_urb(port->read_urb, GFP_ATOMIC);
929 		if (retval)
930 			dev_dbg(&port->dev, "usb_submit_urb(read bulk) failed, retval = %d\n", retval);
931 	}
932 }
933 
934 /*
935  * mos7720_bulk_out_data_callback
936  *	this is the callback function for when we have finished sending serial
937  *	data on the bulk out endpoint.
938  */
939 static void mos7720_bulk_out_data_callback(struct urb *urb)
940 {
941 	struct moschip_port *mos7720_port;
942 	struct tty_struct *tty;
943 	int status = urb->status;
944 
945 	if (status) {
946 		dev_dbg(&urb->dev->dev, "nonzero write bulk status received:%d\n", status);
947 		return;
948 	}
949 
950 	mos7720_port = urb->context;
951 	if (!mos7720_port) {
952 		dev_dbg(&urb->dev->dev, "NULL mos7720_port pointer\n");
953 		return ;
954 	}
955 
956 	tty = tty_port_tty_get(&mos7720_port->port->port);
957 
958 	if (tty && mos7720_port->open)
959 		tty_wakeup(tty);
960 	tty_kref_put(tty);
961 }
962 
963 /*
964  * mos77xx_probe
965  *	this function installs the appropriate read interrupt endpoint callback
966  *	depending on whether the device is a 7720 or 7715, thus avoiding costly
967  *	run-time checks in the high-frequency callback routine itself.
968  */
969 static int mos77xx_probe(struct usb_serial *serial,
970 			 const struct usb_device_id *id)
971 {
972 	if (id->idProduct == MOSCHIP_DEVICE_ID_7715)
973 		moschip7720_2port_driver.read_int_callback =
974 			mos7715_interrupt_callback;
975 	else
976 		moschip7720_2port_driver.read_int_callback =
977 			mos7720_interrupt_callback;
978 
979 	return 0;
980 }
981 
982 static int mos77xx_calc_num_ports(struct usb_serial *serial)
983 {
984 	u16 product = le16_to_cpu(serial->dev->descriptor.idProduct);
985 	if (product == MOSCHIP_DEVICE_ID_7715)
986 		return 1;
987 
988 	return 2;
989 }
990 
991 static int mos7720_open(struct tty_struct *tty, struct usb_serial_port *port)
992 {
993 	struct usb_serial *serial;
994 	struct urb *urb;
995 	struct moschip_port *mos7720_port;
996 	int response;
997 	int port_number;
998 	__u8 data;
999 	int allocated_urbs = 0;
1000 	int j;
1001 
1002 	serial = port->serial;
1003 
1004 	mos7720_port = usb_get_serial_port_data(port);
1005 	if (mos7720_port == NULL)
1006 		return -ENODEV;
1007 
1008 	usb_clear_halt(serial->dev, port->write_urb->pipe);
1009 	usb_clear_halt(serial->dev, port->read_urb->pipe);
1010 
1011 	/* Initialising the write urb pool */
1012 	for (j = 0; j < NUM_URBS; ++j) {
1013 		urb = usb_alloc_urb(0, GFP_KERNEL);
1014 		mos7720_port->write_urb_pool[j] = urb;
1015 
1016 		if (urb == NULL) {
1017 			dev_err(&port->dev, "No more urbs???\n");
1018 			continue;
1019 		}
1020 
1021 		urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE,
1022 					       GFP_KERNEL);
1023 		if (!urb->transfer_buffer) {
1024 			dev_err(&port->dev,
1025 				"%s-out of memory for urb buffers.\n",
1026 				__func__);
1027 			usb_free_urb(mos7720_port->write_urb_pool[j]);
1028 			mos7720_port->write_urb_pool[j] = NULL;
1029 			continue;
1030 		}
1031 		allocated_urbs++;
1032 	}
1033 
1034 	if (!allocated_urbs)
1035 		return -ENOMEM;
1036 
1037 	 /* Initialize MCS7720 -- Write Init values to corresponding Registers
1038 	  *
1039 	  * Register Index
1040 	  * 0 : THR/RHR
1041 	  * 1 : IER
1042 	  * 2 : FCR
1043 	  * 3 : LCR
1044 	  * 4 : MCR
1045 	  * 5 : LSR
1046 	  * 6 : MSR
1047 	  * 7 : SPR
1048 	  *
1049 	  * 0x08 : SP1/2 Control Reg
1050 	  */
1051 	port_number = port->number - port->serial->minor;
1052 	read_mos_reg(serial, port_number, LSR, &data);
1053 
1054 	dev_dbg(&port->dev, "SS::%p LSR:%x\n", mos7720_port, data);
1055 
1056 	write_mos_reg(serial, dummy, SP1_REG, 0x02);
1057 	write_mos_reg(serial, dummy, SP2_REG, 0x02);
1058 
1059 	write_mos_reg(serial, port_number, IER, 0x00);
1060 	write_mos_reg(serial, port_number, FCR, 0x00);
1061 
1062 	write_mos_reg(serial, port_number, FCR, 0xcf);
1063 	mos7720_port->shadowLCR = 0x03;
1064 	write_mos_reg(serial, port_number, LCR, mos7720_port->shadowLCR);
1065 	mos7720_port->shadowMCR = 0x0b;
1066 	write_mos_reg(serial, port_number, MCR, mos7720_port->shadowMCR);
1067 
1068 	write_mos_reg(serial, port_number, SP_CONTROL_REG, 0x00);
1069 	read_mos_reg(serial, dummy, SP_CONTROL_REG, &data);
1070 	data = data | (port->number - port->serial->minor + 1);
1071 	write_mos_reg(serial, dummy, SP_CONTROL_REG, data);
1072 	mos7720_port->shadowLCR = 0x83;
1073 	write_mos_reg(serial, port_number, LCR, mos7720_port->shadowLCR);
1074 	write_mos_reg(serial, port_number, THR, 0x0c);
1075 	write_mos_reg(serial, port_number, IER, 0x00);
1076 	mos7720_port->shadowLCR = 0x03;
1077 	write_mos_reg(serial, port_number, LCR, mos7720_port->shadowLCR);
1078 	write_mos_reg(serial, port_number, IER, 0x0c);
1079 
1080 	response = usb_submit_urb(port->read_urb, GFP_KERNEL);
1081 	if (response)
1082 		dev_err(&port->dev, "%s - Error %d submitting read urb\n",
1083 							__func__, response);
1084 
1085 	/* initialize our icount structure */
1086 	memset(&(mos7720_port->icount), 0x00, sizeof(mos7720_port->icount));
1087 
1088 	/* initialize our port settings */
1089 	mos7720_port->shadowMCR = UART_MCR_OUT2; /* Must set to enable ints! */
1090 
1091 	/* send a open port command */
1092 	mos7720_port->open = 1;
1093 
1094 	return 0;
1095 }
1096 
1097 /*
1098  * mos7720_chars_in_buffer
1099  *	this function is called by the tty driver when it wants to know how many
1100  *	bytes of data we currently have outstanding in the port (data that has
1101  *	been written, but hasn't made it out the port yet)
1102  *	If successful, we return the number of bytes left to be written in the
1103  *	system,
1104  *	Otherwise we return a negative error number.
1105  */
1106 static int mos7720_chars_in_buffer(struct tty_struct *tty)
1107 {
1108 	struct usb_serial_port *port = tty->driver_data;
1109 	int i;
1110 	int chars = 0;
1111 	struct moschip_port *mos7720_port;
1112 
1113 	mos7720_port = usb_get_serial_port_data(port);
1114 	if (mos7720_port == NULL)
1115 		return 0;
1116 
1117 	for (i = 0; i < NUM_URBS; ++i) {
1118 		if (mos7720_port->write_urb_pool[i] &&
1119 		    mos7720_port->write_urb_pool[i]->status == -EINPROGRESS)
1120 			chars += URB_TRANSFER_BUFFER_SIZE;
1121 	}
1122 	dev_dbg(&port->dev, "%s - returns %d\n", __func__, chars);
1123 	return chars;
1124 }
1125 
1126 static void mos7720_close(struct usb_serial_port *port)
1127 {
1128 	struct usb_serial *serial;
1129 	struct moschip_port *mos7720_port;
1130 	int j;
1131 
1132 	serial = port->serial;
1133 
1134 	mos7720_port = usb_get_serial_port_data(port);
1135 	if (mos7720_port == NULL)
1136 		return;
1137 
1138 	for (j = 0; j < NUM_URBS; ++j)
1139 		usb_kill_urb(mos7720_port->write_urb_pool[j]);
1140 
1141 	/* Freeing Write URBs */
1142 	for (j = 0; j < NUM_URBS; ++j) {
1143 		if (mos7720_port->write_urb_pool[j]) {
1144 			kfree(mos7720_port->write_urb_pool[j]->transfer_buffer);
1145 			usb_free_urb(mos7720_port->write_urb_pool[j]);
1146 		}
1147 	}
1148 
1149 	/* While closing port, shutdown all bulk read, write  *
1150 	 * and interrupt read if they exists, otherwise nop   */
1151 	usb_kill_urb(port->write_urb);
1152 	usb_kill_urb(port->read_urb);
1153 
1154 	mutex_lock(&serial->disc_mutex);
1155 	/* these commands must not be issued if the device has
1156 	 * been disconnected */
1157 	if (!serial->disconnected) {
1158 		write_mos_reg(serial, port->number - port->serial->minor,
1159 			      MCR, 0x00);
1160 		write_mos_reg(serial, port->number - port->serial->minor,
1161 			      IER, 0x00);
1162 	}
1163 	mutex_unlock(&serial->disc_mutex);
1164 	mos7720_port->open = 0;
1165 }
1166 
1167 static void mos7720_break(struct tty_struct *tty, int break_state)
1168 {
1169 	struct usb_serial_port *port = tty->driver_data;
1170 	unsigned char data;
1171 	struct usb_serial *serial;
1172 	struct moschip_port *mos7720_port;
1173 
1174 	serial = port->serial;
1175 
1176 	mos7720_port = usb_get_serial_port_data(port);
1177 	if (mos7720_port == NULL)
1178 		return;
1179 
1180 	if (break_state == -1)
1181 		data = mos7720_port->shadowLCR | UART_LCR_SBC;
1182 	else
1183 		data = mos7720_port->shadowLCR & ~UART_LCR_SBC;
1184 
1185 	mos7720_port->shadowLCR  = data;
1186 	write_mos_reg(serial, port->number - port->serial->minor,
1187 		      LCR, mos7720_port->shadowLCR);
1188 }
1189 
1190 /*
1191  * mos7720_write_room
1192  *	this function is called by the tty driver when it wants to know how many
1193  *	bytes of data we can accept for a specific port.
1194  *	If successful, we return the amount of room that we have for this port
1195  *	Otherwise we return a negative error number.
1196  */
1197 static int mos7720_write_room(struct tty_struct *tty)
1198 {
1199 	struct usb_serial_port *port = tty->driver_data;
1200 	struct moschip_port *mos7720_port;
1201 	int room = 0;
1202 	int i;
1203 
1204 	mos7720_port = usb_get_serial_port_data(port);
1205 	if (mos7720_port == NULL)
1206 		return -ENODEV;
1207 
1208 	/* FIXME: Locking */
1209 	for (i = 0; i < NUM_URBS; ++i) {
1210 		if (mos7720_port->write_urb_pool[i] &&
1211 		    mos7720_port->write_urb_pool[i]->status != -EINPROGRESS)
1212 			room += URB_TRANSFER_BUFFER_SIZE;
1213 	}
1214 
1215 	dev_dbg(&port->dev, "%s - returns %d\n", __func__, room);
1216 	return room;
1217 }
1218 
1219 static int mos7720_write(struct tty_struct *tty, struct usb_serial_port *port,
1220 				 const unsigned char *data, int count)
1221 {
1222 	int status;
1223 	int i;
1224 	int bytes_sent = 0;
1225 	int transfer_size;
1226 
1227 	struct moschip_port *mos7720_port;
1228 	struct usb_serial *serial;
1229 	struct urb    *urb;
1230 	const unsigned char *current_position = data;
1231 
1232 	serial = port->serial;
1233 
1234 	mos7720_port = usb_get_serial_port_data(port);
1235 	if (mos7720_port == NULL)
1236 		return -ENODEV;
1237 
1238 	/* try to find a free urb in the list */
1239 	urb = NULL;
1240 
1241 	for (i = 0; i < NUM_URBS; ++i) {
1242 		if (mos7720_port->write_urb_pool[i] &&
1243 		    mos7720_port->write_urb_pool[i]->status != -EINPROGRESS) {
1244 			urb = mos7720_port->write_urb_pool[i];
1245 			dev_dbg(&port->dev, "URB:%d\n", i);
1246 			break;
1247 		}
1248 	}
1249 
1250 	if (urb == NULL) {
1251 		dev_dbg(&port->dev, "%s - no more free urbs\n", __func__);
1252 		goto exit;
1253 	}
1254 
1255 	if (urb->transfer_buffer == NULL) {
1256 		urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE,
1257 					       GFP_KERNEL);
1258 		if (urb->transfer_buffer == NULL) {
1259 			dev_err_console(port, "%s no more kernel memory...\n",
1260 				__func__);
1261 			goto exit;
1262 		}
1263 	}
1264 	transfer_size = min(count, URB_TRANSFER_BUFFER_SIZE);
1265 
1266 	memcpy(urb->transfer_buffer, current_position, transfer_size);
1267 	usb_serial_debug_data(&port->dev, __func__, transfer_size,
1268 			      urb->transfer_buffer);
1269 
1270 	/* fill urb with data and submit  */
1271 	usb_fill_bulk_urb(urb, serial->dev,
1272 			  usb_sndbulkpipe(serial->dev,
1273 					port->bulk_out_endpointAddress),
1274 			  urb->transfer_buffer, transfer_size,
1275 			  mos7720_bulk_out_data_callback, mos7720_port);
1276 
1277 	/* send it down the pipe */
1278 	status = usb_submit_urb(urb, GFP_ATOMIC);
1279 	if (status) {
1280 		dev_err_console(port, "%s - usb_submit_urb(write bulk) failed "
1281 			"with status = %d\n", __func__, status);
1282 		bytes_sent = status;
1283 		goto exit;
1284 	}
1285 	bytes_sent = transfer_size;
1286 
1287 exit:
1288 	return bytes_sent;
1289 }
1290 
1291 static void mos7720_throttle(struct tty_struct *tty)
1292 {
1293 	struct usb_serial_port *port = tty->driver_data;
1294 	struct moschip_port *mos7720_port;
1295 	int status;
1296 
1297 	mos7720_port = usb_get_serial_port_data(port);
1298 
1299 	if (mos7720_port == NULL)
1300 		return;
1301 
1302 	if (!mos7720_port->open) {
1303 		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
1304 		return;
1305 	}
1306 
1307 	/* if we are implementing XON/XOFF, send the stop character */
1308 	if (I_IXOFF(tty)) {
1309 		unsigned char stop_char = STOP_CHAR(tty);
1310 		status = mos7720_write(tty, port, &stop_char, 1);
1311 		if (status <= 0)
1312 			return;
1313 	}
1314 
1315 	/* if we are implementing RTS/CTS, toggle that line */
1316 	if (tty->termios.c_cflag & CRTSCTS) {
1317 		mos7720_port->shadowMCR &= ~UART_MCR_RTS;
1318 		write_mos_reg(port->serial, port->number - port->serial->minor,
1319 			      MCR, mos7720_port->shadowMCR);
1320 		if (status != 0)
1321 			return;
1322 	}
1323 }
1324 
1325 static void mos7720_unthrottle(struct tty_struct *tty)
1326 {
1327 	struct usb_serial_port *port = tty->driver_data;
1328 	struct moschip_port *mos7720_port = usb_get_serial_port_data(port);
1329 	int status;
1330 
1331 	if (mos7720_port == NULL)
1332 		return;
1333 
1334 	if (!mos7720_port->open) {
1335 		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
1336 		return;
1337 	}
1338 
1339 	/* if we are implementing XON/XOFF, send the start character */
1340 	if (I_IXOFF(tty)) {
1341 		unsigned char start_char = START_CHAR(tty);
1342 		status = mos7720_write(tty, port, &start_char, 1);
1343 		if (status <= 0)
1344 			return;
1345 	}
1346 
1347 	/* if we are implementing RTS/CTS, toggle that line */
1348 	if (tty->termios.c_cflag & CRTSCTS) {
1349 		mos7720_port->shadowMCR |= UART_MCR_RTS;
1350 		write_mos_reg(port->serial, port->number - port->serial->minor,
1351 			      MCR, mos7720_port->shadowMCR);
1352 		if (status != 0)
1353 			return;
1354 	}
1355 }
1356 
1357 /* FIXME: this function does not work */
1358 static int set_higher_rates(struct moschip_port *mos7720_port,
1359 			    unsigned int baud)
1360 {
1361 	struct usb_serial_port *port;
1362 	struct usb_serial *serial;
1363 	int port_number;
1364 	enum mos_regs sp_reg;
1365 	if (mos7720_port == NULL)
1366 		return -EINVAL;
1367 
1368 	port = mos7720_port->port;
1369 	serial = port->serial;
1370 
1371 	 /***********************************************
1372 	 *      Init Sequence for higher rates
1373 	 ***********************************************/
1374 	dev_dbg(&port->dev, "Sending Setting Commands ..........\n");
1375 	port_number = port->number - port->serial->minor;
1376 
1377 	write_mos_reg(serial, port_number, IER, 0x00);
1378 	write_mos_reg(serial, port_number, FCR, 0x00);
1379 	write_mos_reg(serial, port_number, FCR, 0xcf);
1380 	mos7720_port->shadowMCR = 0x0b;
1381 	write_mos_reg(serial, port_number, MCR, mos7720_port->shadowMCR);
1382 	write_mos_reg(serial, dummy, SP_CONTROL_REG, 0x00);
1383 
1384 	/***********************************************
1385 	 *              Set for higher rates           *
1386 	 ***********************************************/
1387 	/* writing baud rate verbatum into uart clock field clearly not right */
1388 	if (port_number == 0)
1389 		sp_reg = SP1_REG;
1390 	else
1391 		sp_reg = SP2_REG;
1392 	write_mos_reg(serial, dummy, sp_reg, baud * 0x10);
1393 	write_mos_reg(serial, dummy, SP_CONTROL_REG, 0x03);
1394 	mos7720_port->shadowMCR = 0x2b;
1395 	write_mos_reg(serial, port_number, MCR, mos7720_port->shadowMCR);
1396 
1397 	/***********************************************
1398 	 *              Set DLL/DLM
1399 	 ***********************************************/
1400 	mos7720_port->shadowLCR = mos7720_port->shadowLCR | UART_LCR_DLAB;
1401 	write_mos_reg(serial, port_number, LCR, mos7720_port->shadowLCR);
1402 	write_mos_reg(serial, port_number, DLL, 0x01);
1403 	write_mos_reg(serial, port_number, DLM, 0x00);
1404 	mos7720_port->shadowLCR = mos7720_port->shadowLCR & ~UART_LCR_DLAB;
1405 	write_mos_reg(serial, port_number, LCR, mos7720_port->shadowLCR);
1406 
1407 	return 0;
1408 }
1409 
1410 /* baud rate information */
1411 struct divisor_table_entry {
1412 	__u32  baudrate;
1413 	__u16  divisor;
1414 };
1415 
1416 /* Define table of divisors for moschip 7720 hardware	   *
1417  * These assume a 3.6864MHz crystal, the standard /16, and *
1418  * MCR.7 = 0.						   */
1419 static struct divisor_table_entry divisor_table[] = {
1420 	{   50,		2304},
1421 	{   110,	1047},	/* 2094.545455 => 230450   => .0217 % over */
1422 	{   134,	857},	/* 1713.011152 => 230398.5 => .00065% under */
1423 	{   150,	768},
1424 	{   300,	384},
1425 	{   600,	192},
1426 	{   1200,	96},
1427 	{   1800,	64},
1428 	{   2400,	48},
1429 	{   4800,	24},
1430 	{   7200,	16},
1431 	{   9600,	12},
1432 	{   19200,	6},
1433 	{   38400,	3},
1434 	{   57600,	2},
1435 	{   115200,	1},
1436 };
1437 
1438 /*****************************************************************************
1439  * calc_baud_rate_divisor
1440  *	this function calculates the proper baud rate divisor for the specified
1441  *	baud rate.
1442  *****************************************************************************/
1443 static int calc_baud_rate_divisor(struct usb_serial_port *port, int baudrate, int *divisor)
1444 {
1445 	int i;
1446 	__u16 custom;
1447 	__u16 round1;
1448 	__u16 round;
1449 
1450 
1451 	dev_dbg(&port->dev, "%s - %d\n", __func__, baudrate);
1452 
1453 	for (i = 0; i < ARRAY_SIZE(divisor_table); i++) {
1454 		if (divisor_table[i].baudrate == baudrate) {
1455 			*divisor = divisor_table[i].divisor;
1456 			return 0;
1457 		}
1458 	}
1459 
1460 	/* After trying for all the standard baud rates    *
1461 	 * Try calculating the divisor for this baud rate  */
1462 	if (baudrate > 75 &&  baudrate < 230400) {
1463 		/* get the divisor */
1464 		custom = (__u16)(230400L  / baudrate);
1465 
1466 		/* Check for round off */
1467 		round1 = (__u16)(2304000L / baudrate);
1468 		round = (__u16)(round1 - (custom * 10));
1469 		if (round > 4)
1470 			custom++;
1471 		*divisor = custom;
1472 
1473 		dev_dbg(&port->dev, "Baud %d = %d\n", baudrate, custom);
1474 		return 0;
1475 	}
1476 
1477 	dev_dbg(&port->dev, "Baud calculation Failed...\n");
1478 	return -EINVAL;
1479 }
1480 
1481 /*
1482  * send_cmd_write_baud_rate
1483  *	this function sends the proper command to change the baud rate of the
1484  *	specified port.
1485  */
1486 static int send_cmd_write_baud_rate(struct moschip_port *mos7720_port,
1487 				    int baudrate)
1488 {
1489 	struct usb_serial_port *port;
1490 	struct usb_serial *serial;
1491 	int divisor;
1492 	int status;
1493 	unsigned char number;
1494 
1495 	if (mos7720_port == NULL)
1496 		return -1;
1497 
1498 	port = mos7720_port->port;
1499 	serial = port->serial;
1500 
1501 	number = port->number - port->serial->minor;
1502 	dev_dbg(&port->dev, "%s - baud = %d\n", __func__, baudrate);
1503 
1504 	/* Calculate the Divisor */
1505 	status = calc_baud_rate_divisor(port, baudrate, &divisor);
1506 	if (status) {
1507 		dev_err(&port->dev, "%s - bad baud rate\n", __func__);
1508 		return status;
1509 	}
1510 
1511 	/* Enable access to divisor latch */
1512 	mos7720_port->shadowLCR = mos7720_port->shadowLCR | UART_LCR_DLAB;
1513 	write_mos_reg(serial, number, LCR, mos7720_port->shadowLCR);
1514 
1515 	/* Write the divisor */
1516 	write_mos_reg(serial, number, DLL, (__u8)(divisor & 0xff));
1517 	write_mos_reg(serial, number, DLM, (__u8)((divisor & 0xff00) >> 8));
1518 
1519 	/* Disable access to divisor latch */
1520 	mos7720_port->shadowLCR = mos7720_port->shadowLCR & ~UART_LCR_DLAB;
1521 	write_mos_reg(serial, number, LCR, mos7720_port->shadowLCR);
1522 
1523 	return status;
1524 }
1525 
1526 /*
1527  * change_port_settings
1528  *	This routine is called to set the UART on the device to match
1529  *      the specified new settings.
1530  */
1531 static void change_port_settings(struct tty_struct *tty,
1532 				 struct moschip_port *mos7720_port,
1533 				 struct ktermios *old_termios)
1534 {
1535 	struct usb_serial_port *port;
1536 	struct usb_serial *serial;
1537 	int baud;
1538 	unsigned cflag;
1539 	unsigned iflag;
1540 	__u8 mask = 0xff;
1541 	__u8 lData;
1542 	__u8 lParity;
1543 	__u8 lStop;
1544 	int status;
1545 	int port_number;
1546 
1547 	if (mos7720_port == NULL)
1548 		return ;
1549 
1550 	port = mos7720_port->port;
1551 	serial = port->serial;
1552 	port_number = port->number - port->serial->minor;
1553 
1554 	if (!mos7720_port->open) {
1555 		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
1556 		return;
1557 	}
1558 
1559 	lData = UART_LCR_WLEN8;
1560 	lStop = 0x00;	/* 1 stop bit */
1561 	lParity = 0x00;	/* No parity */
1562 
1563 	cflag = tty->termios.c_cflag;
1564 	iflag = tty->termios.c_iflag;
1565 
1566 	/* Change the number of bits */
1567 	switch (cflag & CSIZE) {
1568 	case CS5:
1569 		lData = UART_LCR_WLEN5;
1570 		mask = 0x1f;
1571 		break;
1572 
1573 	case CS6:
1574 		lData = UART_LCR_WLEN6;
1575 		mask = 0x3f;
1576 		break;
1577 
1578 	case CS7:
1579 		lData = UART_LCR_WLEN7;
1580 		mask = 0x7f;
1581 		break;
1582 	default:
1583 	case CS8:
1584 		lData = UART_LCR_WLEN8;
1585 		break;
1586 	}
1587 
1588 	/* Change the Parity bit */
1589 	if (cflag & PARENB) {
1590 		if (cflag & PARODD) {
1591 			lParity = UART_LCR_PARITY;
1592 			dev_dbg(&port->dev, "%s - parity = odd\n", __func__);
1593 		} else {
1594 			lParity = (UART_LCR_EPAR | UART_LCR_PARITY);
1595 			dev_dbg(&port->dev, "%s - parity = even\n", __func__);
1596 		}
1597 
1598 	} else {
1599 		dev_dbg(&port->dev, "%s - parity = none\n", __func__);
1600 	}
1601 
1602 	if (cflag & CMSPAR)
1603 		lParity = lParity | 0x20;
1604 
1605 	/* Change the Stop bit */
1606 	if (cflag & CSTOPB) {
1607 		lStop = UART_LCR_STOP;
1608 		dev_dbg(&port->dev, "%s - stop bits = 2\n", __func__);
1609 	} else {
1610 		lStop = 0x00;
1611 		dev_dbg(&port->dev, "%s - stop bits = 1\n", __func__);
1612 	}
1613 
1614 #define LCR_BITS_MASK		0x03	/* Mask for bits/char field */
1615 #define LCR_STOP_MASK		0x04	/* Mask for stop bits field */
1616 #define LCR_PAR_MASK		0x38	/* Mask for parity field */
1617 
1618 	/* Update the LCR with the correct value */
1619 	mos7720_port->shadowLCR &=
1620 		~(LCR_BITS_MASK | LCR_STOP_MASK | LCR_PAR_MASK);
1621 	mos7720_port->shadowLCR |= (lData | lParity | lStop);
1622 
1623 
1624 	/* Disable Interrupts */
1625 	write_mos_reg(serial, port_number, IER, 0x00);
1626 	write_mos_reg(serial, port_number, FCR, 0x00);
1627 	write_mos_reg(serial, port_number, FCR, 0xcf);
1628 
1629 	/* Send the updated LCR value to the mos7720 */
1630 	write_mos_reg(serial, port_number, LCR, mos7720_port->shadowLCR);
1631 	mos7720_port->shadowMCR = 0x0b;
1632 	write_mos_reg(serial, port_number, MCR, mos7720_port->shadowMCR);
1633 
1634 	/* set up the MCR register and send it to the mos7720 */
1635 	mos7720_port->shadowMCR = UART_MCR_OUT2;
1636 	if (cflag & CBAUD)
1637 		mos7720_port->shadowMCR |= (UART_MCR_DTR | UART_MCR_RTS);
1638 
1639 	if (cflag & CRTSCTS) {
1640 		mos7720_port->shadowMCR |= (UART_MCR_XONANY);
1641 		/* To set hardware flow control to the specified *
1642 		 * serial port, in SP1/2_CONTROL_REG             */
1643 		if (port->number)
1644 			write_mos_reg(serial, dummy, SP_CONTROL_REG, 0x01);
1645 		else
1646 			write_mos_reg(serial, dummy, SP_CONTROL_REG, 0x02);
1647 
1648 	} else
1649 		mos7720_port->shadowMCR &= ~(UART_MCR_XONANY);
1650 
1651 	write_mos_reg(serial, port_number, MCR, mos7720_port->shadowMCR);
1652 
1653 	/* Determine divisor based on baud rate */
1654 	baud = tty_get_baud_rate(tty);
1655 	if (!baud) {
1656 		/* pick a default, any default... */
1657 		dev_dbg(&port->dev, "Picked default baud...\n");
1658 		baud = 9600;
1659 	}
1660 
1661 	if (baud >= 230400) {
1662 		set_higher_rates(mos7720_port, baud);
1663 		/* Enable Interrupts */
1664 		write_mos_reg(serial, port_number, IER, 0x0c);
1665 		return;
1666 	}
1667 
1668 	dev_dbg(&port->dev, "%s - baud rate = %d\n", __func__, baud);
1669 	status = send_cmd_write_baud_rate(mos7720_port, baud);
1670 	/* FIXME: needs to write actual resulting baud back not just
1671 	   blindly do so */
1672 	if (cflag & CBAUD)
1673 		tty_encode_baud_rate(tty, baud, baud);
1674 	/* Enable Interrupts */
1675 	write_mos_reg(serial, port_number, IER, 0x0c);
1676 
1677 	if (port->read_urb->status != -EINPROGRESS) {
1678 		status = usb_submit_urb(port->read_urb, GFP_ATOMIC);
1679 		if (status)
1680 			dev_dbg(&port->dev, "usb_submit_urb(read bulk) failed, status = %d\n", status);
1681 	}
1682 }
1683 
1684 /*
1685  * mos7720_set_termios
1686  *	this function is called by the tty driver when it wants to change the
1687  *	termios structure.
1688  */
1689 static void mos7720_set_termios(struct tty_struct *tty,
1690 		struct usb_serial_port *port, struct ktermios *old_termios)
1691 {
1692 	int status;
1693 	unsigned int cflag;
1694 	struct usb_serial *serial;
1695 	struct moschip_port *mos7720_port;
1696 
1697 	serial = port->serial;
1698 
1699 	mos7720_port = usb_get_serial_port_data(port);
1700 
1701 	if (mos7720_port == NULL)
1702 		return;
1703 
1704 	if (!mos7720_port->open) {
1705 		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
1706 		return;
1707 	}
1708 
1709 	dev_dbg(&port->dev, "setting termios - ASPIRE\n");
1710 
1711 	cflag = tty->termios.c_cflag;
1712 
1713 	dev_dbg(&port->dev, "%s - cflag %08x iflag %08x\n", __func__,
1714 		tty->termios.c_cflag, RELEVANT_IFLAG(tty->termios.c_iflag));
1715 
1716 	dev_dbg(&port->dev, "%s - old cflag %08x old iflag %08x\n", __func__,
1717 		old_termios->c_cflag, RELEVANT_IFLAG(old_termios->c_iflag));
1718 
1719 	/* change the port settings to the new ones specified */
1720 	change_port_settings(tty, mos7720_port, old_termios);
1721 
1722 	if (port->read_urb->status != -EINPROGRESS) {
1723 		status = usb_submit_urb(port->read_urb, GFP_ATOMIC);
1724 		if (status)
1725 			dev_dbg(&port->dev, "usb_submit_urb(read bulk) failed, status = %d\n", status);
1726 	}
1727 }
1728 
1729 /*
1730  * get_lsr_info - get line status register info
1731  *
1732  * Purpose: Let user call ioctl() to get info when the UART physically
1733  * 	    is emptied.  On bus types like RS485, the transmitter must
1734  * 	    release the bus after transmitting. This must be done when
1735  * 	    the transmit shift register is empty, not be done when the
1736  * 	    transmit holding register is empty.  This functionality
1737  * 	    allows an RS485 driver to be written in user space.
1738  */
1739 static int get_lsr_info(struct tty_struct *tty,
1740 		struct moschip_port *mos7720_port, unsigned int __user *value)
1741 {
1742 	struct usb_serial_port *port = tty->driver_data;
1743 	unsigned int result = 0;
1744 	unsigned char data = 0;
1745 	int port_number = port->number - port->serial->minor;
1746 	int count;
1747 
1748 	count = mos7720_chars_in_buffer(tty);
1749 	if (count == 0) {
1750 		read_mos_reg(port->serial, port_number, LSR, &data);
1751 		if ((data & (UART_LSR_TEMT | UART_LSR_THRE))
1752 					== (UART_LSR_TEMT | UART_LSR_THRE)) {
1753 			dev_dbg(&port->dev, "%s -- Empty\n", __func__);
1754 			result = TIOCSER_TEMT;
1755 		}
1756 	}
1757 	if (copy_to_user(value, &result, sizeof(int)))
1758 		return -EFAULT;
1759 	return 0;
1760 }
1761 
1762 static int mos7720_tiocmget(struct tty_struct *tty)
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 result = 0;
1767 	unsigned int mcr ;
1768 	unsigned int msr ;
1769 
1770 	mcr = mos7720_port->shadowMCR;
1771 	msr = mos7720_port->shadowMSR;
1772 
1773 	result = ((mcr & UART_MCR_DTR)  ? TIOCM_DTR : 0)   /* 0x002 */
1774 	  | ((mcr & UART_MCR_RTS)   ? TIOCM_RTS : 0)   /* 0x004 */
1775 	  | ((msr & UART_MSR_CTS)   ? TIOCM_CTS : 0)   /* 0x020 */
1776 	  | ((msr & UART_MSR_DCD)   ? TIOCM_CAR : 0)   /* 0x040 */
1777 	  | ((msr & UART_MSR_RI)    ? TIOCM_RI :  0)   /* 0x080 */
1778 	  | ((msr & UART_MSR_DSR)   ? TIOCM_DSR : 0);  /* 0x100 */
1779 
1780 	return result;
1781 }
1782 
1783 static int mos7720_tiocmset(struct tty_struct *tty,
1784 			    unsigned int set, unsigned int clear)
1785 {
1786 	struct usb_serial_port *port = tty->driver_data;
1787 	struct moschip_port *mos7720_port = usb_get_serial_port_data(port);
1788 	unsigned int mcr ;
1789 
1790 	mcr = mos7720_port->shadowMCR;
1791 
1792 	if (set & TIOCM_RTS)
1793 		mcr |= UART_MCR_RTS;
1794 	if (set & TIOCM_DTR)
1795 		mcr |= UART_MCR_DTR;
1796 	if (set & TIOCM_LOOP)
1797 		mcr |= UART_MCR_LOOP;
1798 
1799 	if (clear & TIOCM_RTS)
1800 		mcr &= ~UART_MCR_RTS;
1801 	if (clear & TIOCM_DTR)
1802 		mcr &= ~UART_MCR_DTR;
1803 	if (clear & TIOCM_LOOP)
1804 		mcr &= ~UART_MCR_LOOP;
1805 
1806 	mos7720_port->shadowMCR = mcr;
1807 	write_mos_reg(port->serial, port->number - port->serial->minor,
1808 		      MCR, mos7720_port->shadowMCR);
1809 
1810 	return 0;
1811 }
1812 
1813 static int mos7720_get_icount(struct tty_struct *tty,
1814 				struct serial_icounter_struct *icount)
1815 {
1816 	struct usb_serial_port *port = tty->driver_data;
1817 	struct moschip_port *mos7720_port;
1818 	struct async_icount cnow;
1819 
1820 	mos7720_port = usb_get_serial_port_data(port);
1821 	cnow = mos7720_port->icount;
1822 
1823 	icount->cts = cnow.cts;
1824 	icount->dsr = cnow.dsr;
1825 	icount->rng = cnow.rng;
1826 	icount->dcd = cnow.dcd;
1827 	icount->rx = cnow.rx;
1828 	icount->tx = cnow.tx;
1829 	icount->frame = cnow.frame;
1830 	icount->overrun = cnow.overrun;
1831 	icount->parity = cnow.parity;
1832 	icount->brk = cnow.brk;
1833 	icount->buf_overrun = cnow.buf_overrun;
1834 
1835 	dev_dbg(&port->dev, "%s TIOCGICOUNT RX=%d, TX=%d\n", __func__,
1836 		icount->rx, icount->tx);
1837 	return 0;
1838 }
1839 
1840 static int set_modem_info(struct moschip_port *mos7720_port, unsigned int cmd,
1841 			  unsigned int __user *value)
1842 {
1843 	unsigned int mcr;
1844 	unsigned int arg;
1845 
1846 	struct usb_serial_port *port;
1847 
1848 	if (mos7720_port == NULL)
1849 		return -1;
1850 
1851 	port = (struct usb_serial_port *)mos7720_port->port;
1852 	mcr = mos7720_port->shadowMCR;
1853 
1854 	if (copy_from_user(&arg, value, sizeof(int)))
1855 		return -EFAULT;
1856 
1857 	switch (cmd) {
1858 	case TIOCMBIS:
1859 		if (arg & TIOCM_RTS)
1860 			mcr |= UART_MCR_RTS;
1861 		if (arg & TIOCM_DTR)
1862 			mcr |= UART_MCR_RTS;
1863 		if (arg & TIOCM_LOOP)
1864 			mcr |= UART_MCR_LOOP;
1865 		break;
1866 
1867 	case TIOCMBIC:
1868 		if (arg & TIOCM_RTS)
1869 			mcr &= ~UART_MCR_RTS;
1870 		if (arg & TIOCM_DTR)
1871 			mcr &= ~UART_MCR_RTS;
1872 		if (arg & TIOCM_LOOP)
1873 			mcr &= ~UART_MCR_LOOP;
1874 		break;
1875 
1876 	}
1877 
1878 	mos7720_port->shadowMCR = mcr;
1879 	write_mos_reg(port->serial, port->number - port->serial->minor,
1880 		      MCR, mos7720_port->shadowMCR);
1881 
1882 	return 0;
1883 }
1884 
1885 static int get_serial_info(struct moschip_port *mos7720_port,
1886 			   struct serial_struct __user *retinfo)
1887 {
1888 	struct serial_struct tmp;
1889 
1890 	if (!retinfo)
1891 		return -EFAULT;
1892 
1893 	memset(&tmp, 0, sizeof(tmp));
1894 
1895 	tmp.type		= PORT_16550A;
1896 	tmp.line		= mos7720_port->port->serial->minor;
1897 	tmp.port		= mos7720_port->port->number;
1898 	tmp.irq			= 0;
1899 	tmp.flags		= ASYNC_SKIP_TEST | ASYNC_AUTO_IRQ;
1900 	tmp.xmit_fifo_size	= NUM_URBS * URB_TRANSFER_BUFFER_SIZE;
1901 	tmp.baud_base		= 9600;
1902 	tmp.close_delay		= 5*HZ;
1903 	tmp.closing_wait	= 30*HZ;
1904 
1905 	if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
1906 		return -EFAULT;
1907 	return 0;
1908 }
1909 
1910 static int mos7720_ioctl(struct tty_struct *tty,
1911 			 unsigned int cmd, unsigned long arg)
1912 {
1913 	struct usb_serial_port *port = tty->driver_data;
1914 	struct moschip_port *mos7720_port;
1915 	struct async_icount cnow;
1916 	struct async_icount cprev;
1917 
1918 	mos7720_port = usb_get_serial_port_data(port);
1919 	if (mos7720_port == NULL)
1920 		return -ENODEV;
1921 
1922 	dev_dbg(&port->dev, "%s - cmd = 0x%x", __func__, cmd);
1923 
1924 	switch (cmd) {
1925 	case TIOCSERGETLSR:
1926 		dev_dbg(&port->dev, "%s TIOCSERGETLSR\n", __func__);
1927 		return get_lsr_info(tty, mos7720_port,
1928 					(unsigned int __user *)arg);
1929 
1930 	/* FIXME: These should be using the mode methods */
1931 	case TIOCMBIS:
1932 	case TIOCMBIC:
1933 		dev_dbg(&port->dev, "%s TIOCMSET/TIOCMBIC/TIOCMSET\n", __func__);
1934 		return set_modem_info(mos7720_port, cmd,
1935 				      (unsigned int __user *)arg);
1936 
1937 	case TIOCGSERIAL:
1938 		dev_dbg(&port->dev, "%s TIOCGSERIAL\n", __func__);
1939 		return get_serial_info(mos7720_port,
1940 				       (struct serial_struct __user *)arg);
1941 
1942 	case TIOCMIWAIT:
1943 		dev_dbg(&port->dev, "%s TIOCMIWAIT\n", __func__);
1944 		cprev = mos7720_port->icount;
1945 		while (1) {
1946 			if (signal_pending(current))
1947 				return -ERESTARTSYS;
1948 			cnow = mos7720_port->icount;
1949 			if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
1950 			    cnow.dcd == cprev.dcd && cnow.cts == cprev.cts)
1951 				return -EIO; /* no change => error */
1952 			if (((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) ||
1953 			    ((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) ||
1954 			    ((arg & TIOCM_CD)  && (cnow.dcd != cprev.dcd)) ||
1955 			    ((arg & TIOCM_CTS) && (cnow.cts != cprev.cts))) {
1956 				return 0;
1957 			}
1958 			cprev = cnow;
1959 		}
1960 		/* NOTREACHED */
1961 		break;
1962 	}
1963 
1964 	return -ENOIOCTLCMD;
1965 }
1966 
1967 static int mos7720_startup(struct usb_serial *serial)
1968 {
1969 	struct usb_device *dev;
1970 	char data;
1971 	u16 product;
1972 	int ret_val;
1973 
1974 	product = le16_to_cpu(serial->dev->descriptor.idProduct);
1975 	dev = serial->dev;
1976 
1977 	/*
1978 	 * The 7715 uses the first bulk in/out endpoint pair for the parallel
1979 	 * port, and the second for the serial port.  Because the usbserial core
1980 	 * assumes both pairs are serial ports, we must engage in a bit of
1981 	 * subterfuge and swap the pointers for ports 0 and 1 in order to make
1982 	 * port 0 point to the serial port.  However, both moschip devices use a
1983 	 * single interrupt-in endpoint for both ports (as mentioned a little
1984 	 * further down), and this endpoint was assigned to port 0.  So after
1985 	 * the swap, we must copy the interrupt endpoint elements from port 1
1986 	 * (as newly assigned) to port 0, and null out port 1 pointers.
1987 	 */
1988 	if (product == MOSCHIP_DEVICE_ID_7715) {
1989 		struct usb_serial_port *tmp = serial->port[0];
1990 		serial->port[0] = serial->port[1];
1991 		serial->port[1] = tmp;
1992 		serial->port[0]->interrupt_in_urb = tmp->interrupt_in_urb;
1993 		serial->port[0]->interrupt_in_buffer = tmp->interrupt_in_buffer;
1994 		serial->port[0]->interrupt_in_endpointAddress =
1995 			tmp->interrupt_in_endpointAddress;
1996 		serial->port[1]->interrupt_in_urb = NULL;
1997 		serial->port[1]->interrupt_in_buffer = NULL;
1998 	}
1999 
2000 	/* setting configuration feature to one */
2001 	usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
2002 			(__u8)0x03, 0x00, 0x01, 0x00, NULL, 0x00, 5*HZ);
2003 
2004 	/* start the interrupt urb */
2005 	ret_val = usb_submit_urb(serial->port[0]->interrupt_in_urb, GFP_KERNEL);
2006 	if (ret_val)
2007 		dev_err(&dev->dev,
2008 			"%s - Error %d submitting control urb\n",
2009 			__func__, ret_val);
2010 
2011 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
2012 	if (product == MOSCHIP_DEVICE_ID_7715) {
2013 		ret_val = mos7715_parport_init(serial);
2014 		if (ret_val < 0)
2015 			return ret_val;
2016 	}
2017 #endif
2018 	/* LSR For Port 1 */
2019 	read_mos_reg(serial, 0, LSR, &data);
2020 	dev_dbg(&dev->dev, "LSR:%x\n", data);
2021 
2022 	return 0;
2023 }
2024 
2025 static void mos7720_release(struct usb_serial *serial)
2026 {
2027 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
2028 	/* close the parallel port */
2029 
2030 	if (le16_to_cpu(serial->dev->descriptor.idProduct)
2031 	    == MOSCHIP_DEVICE_ID_7715) {
2032 		struct urbtracker *urbtrack;
2033 		unsigned long flags;
2034 		struct mos7715_parport *mos_parport =
2035 			usb_get_serial_data(serial);
2036 
2037 		/* prevent NULL ptr dereference in port callbacks */
2038 		spin_lock(&release_lock);
2039 		mos_parport->pp->private_data = NULL;
2040 		spin_unlock(&release_lock);
2041 
2042 		/* wait for synchronous usb calls to return */
2043 		if (mos_parport->msg_pending)
2044 			wait_for_completion_timeout(&mos_parport->syncmsg_compl,
2045 						    MOS_WDR_TIMEOUT);
2046 
2047 		parport_remove_port(mos_parport->pp);
2048 		usb_set_serial_data(serial, NULL);
2049 		mos_parport->serial = NULL;
2050 
2051 		/* if tasklet currently scheduled, wait for it to complete */
2052 		tasklet_kill(&mos_parport->urb_tasklet);
2053 
2054 		/* unlink any urbs sent by the tasklet  */
2055 		spin_lock_irqsave(&mos_parport->listlock, flags);
2056 		list_for_each_entry(urbtrack,
2057 				    &mos_parport->active_urbs,
2058 				    urblist_entry)
2059 			usb_unlink_urb(urbtrack->urb);
2060 		spin_unlock_irqrestore(&mos_parport->listlock, flags);
2061 
2062 		kref_put(&mos_parport->ref_count, destroy_mos_parport);
2063 	}
2064 #endif
2065 }
2066 
2067 static int mos7720_port_probe(struct usb_serial_port *port)
2068 {
2069 	struct moschip_port *mos7720_port;
2070 
2071 	mos7720_port = kzalloc(sizeof(*mos7720_port), GFP_KERNEL);
2072 	if (!mos7720_port)
2073 		return -ENOMEM;
2074 
2075 	/* Initialize all port interrupt end point to port 0 int endpoint.
2076 	 * Our device has only one interrupt endpoint common to all ports.
2077 	 */
2078 	port->interrupt_in_endpointAddress =
2079 		port->serial->port[0]->interrupt_in_endpointAddress;
2080 	mos7720_port->port = port;
2081 
2082 	usb_set_serial_port_data(port, mos7720_port);
2083 
2084 	return 0;
2085 }
2086 
2087 static int mos7720_port_remove(struct usb_serial_port *port)
2088 {
2089 	struct moschip_port *mos7720_port;
2090 
2091 	mos7720_port = usb_get_serial_port_data(port);
2092 	kfree(mos7720_port);
2093 
2094 	return 0;
2095 }
2096 
2097 static struct usb_serial_driver moschip7720_2port_driver = {
2098 	.driver = {
2099 		.owner =	THIS_MODULE,
2100 		.name =		"moschip7720",
2101 	},
2102 	.description		= "Moschip 2 port adapter",
2103 	.id_table		= id_table,
2104 	.calc_num_ports		= mos77xx_calc_num_ports,
2105 	.open			= mos7720_open,
2106 	.close			= mos7720_close,
2107 	.throttle		= mos7720_throttle,
2108 	.unthrottle		= mos7720_unthrottle,
2109 	.probe			= mos77xx_probe,
2110 	.attach			= mos7720_startup,
2111 	.release		= mos7720_release,
2112 	.port_probe		= mos7720_port_probe,
2113 	.port_remove		= mos7720_port_remove,
2114 	.ioctl			= mos7720_ioctl,
2115 	.tiocmget		= mos7720_tiocmget,
2116 	.tiocmset		= mos7720_tiocmset,
2117 	.get_icount		= mos7720_get_icount,
2118 	.set_termios		= mos7720_set_termios,
2119 	.write			= mos7720_write,
2120 	.write_room		= mos7720_write_room,
2121 	.chars_in_buffer	= mos7720_chars_in_buffer,
2122 	.break_ctl		= mos7720_break,
2123 	.read_bulk_callback	= mos7720_bulk_in_callback,
2124 	.read_int_callback	= NULL  /* dynamically assigned in probe() */
2125 };
2126 
2127 static struct usb_serial_driver * const serial_drivers[] = {
2128 	&moschip7720_2port_driver, NULL
2129 };
2130 
2131 module_usb_serial_driver(serial_drivers, id_table);
2132 
2133 MODULE_AUTHOR(DRIVER_AUTHOR);
2134 MODULE_DESCRIPTION(DRIVER_DESC);
2135 MODULE_LICENSE("GPL");
2136