xref: /openbmc/linux/drivers/usb/serial/mos7720.c (revision 95e9fd10)
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 bool debug;
75 
76 static struct usb_serial_driver moschip7720_2port_driver;
77 
78 #define USB_VENDOR_ID_MOSCHIP		0x9710
79 #define MOSCHIP_DEVICE_ID_7720		0x7720
80 #define MOSCHIP_DEVICE_ID_7715		0x7715
81 
82 static const struct usb_device_id id_table[] = {
83 	{ USB_DEVICE(USB_VENDOR_ID_MOSCHIP, MOSCHIP_DEVICE_ID_7720) },
84 	{ USB_DEVICE(USB_VENDOR_ID_MOSCHIP, MOSCHIP_DEVICE_ID_7715) },
85 	{ } /* terminating entry */
86 };
87 MODULE_DEVICE_TABLE(usb, id_table);
88 
89 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
90 
91 /* initial values for parport regs */
92 #define DCR_INIT_VAL       0x0c	/* SLCTIN, nINIT */
93 #define ECR_INIT_VAL       0x00	/* SPP mode */
94 
95 struct urbtracker {
96 	struct mos7715_parport  *mos_parport;
97 	struct list_head        urblist_entry;
98 	struct kref             ref_count;
99 	struct urb              *urb;
100 };
101 
102 enum mos7715_pp_modes {
103 	SPP = 0<<5,
104 	PS2 = 1<<5,      /* moschip calls this 'NIBBLE' mode */
105 	PPF = 2<<5,	 /* moschip calls this 'CB-FIFO mode */
106 };
107 
108 struct mos7715_parport {
109 	struct parport          *pp;	       /* back to containing struct */
110 	struct kref             ref_count;     /* to instance of this struct */
111 	struct list_head        deferred_urbs; /* list deferred async urbs */
112 	struct list_head        active_urbs;   /* list async urbs in flight */
113 	spinlock_t              listlock;      /* protects list access */
114 	bool                    msg_pending;   /* usb sync call pending */
115 	struct completion       syncmsg_compl; /* usb sync call completed */
116 	struct tasklet_struct   urb_tasklet;   /* for sending deferred urbs */
117 	struct usb_serial       *serial;       /* back to containing struct */
118 	__u8	                shadowECR;     /* parallel port regs... */
119 	__u8	                shadowDCR;
120 	atomic_t                shadowDSR;     /* updated in int-in callback */
121 };
122 
123 /* lock guards against dereferencing NULL ptr in parport ops callbacks */
124 static DEFINE_SPINLOCK(release_lock);
125 
126 #endif	/* CONFIG_USB_SERIAL_MOS7715_PARPORT */
127 
128 static const unsigned int dummy; /* for clarity in register access fns */
129 
130 enum mos_regs {
131 	THR,	          /* serial port regs */
132 	RHR,
133 	IER,
134 	FCR,
135 	ISR,
136 	LCR,
137 	MCR,
138 	LSR,
139 	MSR,
140 	SPR,
141 	DLL,
142 	DLM,
143 	DPR,              /* parallel port regs */
144 	DSR,
145 	DCR,
146 	ECR,
147 	SP1_REG,          /* device control regs */
148 	SP2_REG,          /* serial port 2 (7720 only) */
149 	PP_REG,
150 	SP_CONTROL_REG,
151 };
152 
153 /*
154  * Return the correct value for the Windex field of the setup packet
155  * for a control endpoint message.  See the 7715 datasheet.
156  */
157 static inline __u16 get_reg_index(enum mos_regs reg)
158 {
159 	static const __u16 mos7715_index_lookup_table[] = {
160 		0x00,		/* THR */
161 		0x00,		/* RHR */
162 		0x01,		/* IER */
163 		0x02,		/* FCR */
164 		0x02,		/* ISR */
165 		0x03,		/* LCR */
166 		0x04,		/* MCR */
167 		0x05,		/* LSR */
168 		0x06,		/* MSR */
169 		0x07,		/* SPR */
170 		0x00,		/* DLL */
171 		0x01,		/* DLM */
172 		0x00,		/* DPR */
173 		0x01,		/* DSR */
174 		0x02,		/* DCR */
175 		0x0a,		/* ECR */
176 		0x01,		/* SP1_REG */
177 		0x02,		/* SP2_REG (7720 only) */
178 		0x04,		/* PP_REG (7715 only) */
179 		0x08,		/* SP_CONTROL_REG */
180 	};
181 	return mos7715_index_lookup_table[reg];
182 }
183 
184 /*
185  * Return the correct value for the upper byte of the Wvalue field of
186  * the setup packet for a control endpoint message.
187  */
188 static inline __u16 get_reg_value(enum mos_regs reg,
189 				  unsigned int serial_portnum)
190 {
191 	if (reg >= SP1_REG)	      /* control reg */
192 		return 0x0000;
193 
194 	else if (reg >= DPR)	      /* parallel port reg (7715 only) */
195 		return 0x0100;
196 
197 	else			      /* serial port reg */
198 		return (serial_portnum + 2) << 8;
199 }
200 
201 /*
202  * Write data byte to the specified device register.  The data is embedded in
203  * the value field of the setup packet. serial_portnum is ignored for registers
204  * not specific to a particular serial port.
205  */
206 static int write_mos_reg(struct usb_serial *serial, unsigned int serial_portnum,
207 			 enum mos_regs reg, __u8 data)
208 {
209 	struct usb_device *usbdev = serial->dev;
210 	unsigned int pipe = usb_sndctrlpipe(usbdev, 0);
211 	__u8 request = (__u8)0x0e;
212 	__u8 requesttype = (__u8)0x40;
213 	__u16 index = get_reg_index(reg);
214 	__u16 value = get_reg_value(reg, serial_portnum) + data;
215 	int status = usb_control_msg(usbdev, pipe, request, requesttype, value,
216 				     index, NULL, 0, MOS_WDR_TIMEOUT);
217 	if (status < 0)
218 		dev_err(&usbdev->dev,
219 			"mos7720: usb_control_msg() failed: %d", status);
220 	return status;
221 }
222 
223 /*
224  * Read data byte from the specified device register.  The data returned by the
225  * device is embedded in the value field of the setup packet.  serial_portnum is
226  * ignored for registers that are not specific to a particular serial port.
227  */
228 static int read_mos_reg(struct usb_serial *serial, unsigned int serial_portnum,
229 			enum mos_regs reg, __u8 *data)
230 {
231 	struct usb_device *usbdev = serial->dev;
232 	unsigned int pipe = usb_rcvctrlpipe(usbdev, 0);
233 	__u8 request = (__u8)0x0d;
234 	__u8 requesttype = (__u8)0xc0;
235 	__u16 index = get_reg_index(reg);
236 	__u16 value = get_reg_value(reg, serial_portnum);
237 	int status = usb_control_msg(usbdev, pipe, request, requesttype, value,
238 				     index, data, 1, MOS_WDR_TIMEOUT);
239 	if (status < 0)
240 		dev_err(&usbdev->dev,
241 			"mos7720: usb_control_msg() failed: %d", status);
242 	return status;
243 }
244 
245 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
246 
247 static inline int mos7715_change_mode(struct mos7715_parport *mos_parport,
248 				      enum mos7715_pp_modes mode)
249 {
250 	mos_parport->shadowECR = mode;
251 	write_mos_reg(mos_parport->serial, dummy, ECR, mos_parport->shadowECR);
252 	return 0;
253 }
254 
255 static void destroy_mos_parport(struct kref *kref)
256 {
257 	struct mos7715_parport *mos_parport =
258 		container_of(kref, struct mos7715_parport, ref_count);
259 
260 	kfree(mos_parport);
261 }
262 
263 static void destroy_urbtracker(struct kref *kref)
264 {
265 	struct urbtracker *urbtrack =
266 		container_of(kref, struct urbtracker, ref_count);
267 	struct mos7715_parport *mos_parport = urbtrack->mos_parport;
268 
269 	usb_free_urb(urbtrack->urb);
270 	kfree(urbtrack);
271 	kref_put(&mos_parport->ref_count, destroy_mos_parport);
272 }
273 
274 /*
275  * This runs as a tasklet when sending an urb in a non-blocking parallel
276  * port callback had to be deferred because the disconnect mutex could not be
277  * obtained at the time.
278  */
279 static void send_deferred_urbs(unsigned long _mos_parport)
280 {
281 	int ret_val;
282 	unsigned long flags;
283 	struct mos7715_parport *mos_parport = (void *)_mos_parport;
284 	struct urbtracker *urbtrack;
285 	struct list_head *cursor, *next;
286 
287 	/* if release function ran, game over */
288 	if (unlikely(mos_parport->serial == NULL))
289 		return;
290 
291 	/* try again to get the mutex */
292 	if (!mutex_trylock(&mos_parport->serial->disc_mutex)) {
293 		dbg("%s: rescheduling tasklet", __func__);
294 		tasklet_schedule(&mos_parport->urb_tasklet);
295 		return;
296 	}
297 
298 	/* if device disconnected, game over */
299 	if (unlikely(mos_parport->serial->disconnected)) {
300 		mutex_unlock(&mos_parport->serial->disc_mutex);
301 		return;
302 	}
303 
304 	spin_lock_irqsave(&mos_parport->listlock, flags);
305 	if (list_empty(&mos_parport->deferred_urbs)) {
306 		spin_unlock_irqrestore(&mos_parport->listlock, flags);
307 		mutex_unlock(&mos_parport->serial->disc_mutex);
308 		dbg("%s: deferred_urbs list empty", __func__);
309 		return;
310 	}
311 
312 	/* move contents of deferred_urbs list to active_urbs list and submit */
313 	list_for_each_safe(cursor, next, &mos_parport->deferred_urbs)
314 		list_move_tail(cursor, &mos_parport->active_urbs);
315 	list_for_each_entry(urbtrack, &mos_parport->active_urbs,
316 			    urblist_entry) {
317 		ret_val = usb_submit_urb(urbtrack->urb, GFP_ATOMIC);
318 		dbg("%s: urb submitted", __func__);
319 		if (ret_val) {
320 			dev_err(&mos_parport->serial->dev->dev,
321 				"usb_submit_urb() failed: %d", 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 		dbg("%s - nonzero urb status received: %d", __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 		dbg("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 		dbg("mos7715_parport_init: kzalloc failed");
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 	__u8 *data;
747 	__u8 sp1;
748 	__u8 sp2;
749 
750 	switch (status) {
751 	case 0:
752 		/* success */
753 		break;
754 	case -ECONNRESET:
755 	case -ENOENT:
756 	case -ESHUTDOWN:
757 		/* this urb is terminated, clean up */
758 		dbg("%s - urb shutting down with status: %d", __func__,
759 		    status);
760 		return;
761 	default:
762 		dbg("%s - nonzero urb status received: %d", __func__,
763 		    status);
764 		goto exit;
765 	}
766 
767 	length = urb->actual_length;
768 	data = urb->transfer_buffer;
769 
770 	/* Moschip get 4 bytes
771 	 * Byte 1 IIR Port 1 (port.number is 0)
772 	 * Byte 2 IIR Port 2 (port.number is 1)
773 	 * Byte 3 --------------
774 	 * Byte 4 FIFO status for both */
775 
776 	/* the above description is inverted
777 	 * 	oneukum 2007-03-14 */
778 
779 	if (unlikely(length != 4)) {
780 		dbg("Wrong data !!!");
781 		return;
782 	}
783 
784 	sp1 = data[3];
785 	sp2 = data[2];
786 
787 	if ((sp1 | sp2) & 0x01) {
788 		/* No Interrupt Pending in both the ports */
789 		dbg("No Interrupt !!!");
790 	} else {
791 		switch (sp1 & 0x0f) {
792 		case SERIAL_IIR_RLS:
793 			dbg("Serial Port 1: Receiver status error or address "
794 			    "bit detected in 9-bit mode\n");
795 			break;
796 		case SERIAL_IIR_CTI:
797 			dbg("Serial Port 1: Receiver time out");
798 			break;
799 		case SERIAL_IIR_MS:
800 			/* dbg("Serial Port 1: Modem status change"); */
801 			break;
802 		}
803 
804 		switch (sp2 & 0x0f) {
805 		case SERIAL_IIR_RLS:
806 			dbg("Serial Port 2: Receiver status error or address "
807 			    "bit detected in 9-bit mode");
808 			break;
809 		case SERIAL_IIR_CTI:
810 			dbg("Serial Port 2: Receiver time out");
811 			break;
812 		case SERIAL_IIR_MS:
813 			/* dbg("Serial Port 2: Modem status change"); */
814 			break;
815 		}
816 	}
817 
818 exit:
819 	result = usb_submit_urb(urb, GFP_ATOMIC);
820 	if (result)
821 		dev_err(&urb->dev->dev,
822 			"%s - Error %d submitting control urb\n",
823 			__func__, result);
824 }
825 
826 /*
827  * mos7715_interrupt_callback
828  *	this is the 7715's callback function for when we have received data on
829  *	the interrupt endpoint.
830  */
831 static void mos7715_interrupt_callback(struct urb *urb)
832 {
833 	int result;
834 	int length;
835 	int status = urb->status;
836 	__u8 *data;
837 	__u8 iir;
838 
839 	switch (status) {
840 	case 0:
841 		/* success */
842 		break;
843 	case -ECONNRESET:
844 	case -ENOENT:
845 	case -ESHUTDOWN:
846 	case -ENODEV:
847 		/* this urb is terminated, clean up */
848 		dbg("%s - urb shutting down with status: %d", __func__,
849 		    status);
850 		return;
851 	default:
852 		dbg("%s - nonzero urb status received: %d", __func__,
853 		    status);
854 		goto exit;
855 	}
856 
857 	length = urb->actual_length;
858 	data = urb->transfer_buffer;
859 
860 	/* Structure of data from 7715 device:
861 	 * Byte 1: IIR serial Port
862 	 * Byte 2: unused
863 	 * Byte 2: DSR parallel port
864 	 * Byte 4: FIFO status for both */
865 
866 	if (unlikely(length != 4)) {
867 		dbg("Wrong data !!!");
868 		return;
869 	}
870 
871 	iir = data[0];
872 	if (!(iir & 0x01)) {	/* serial port interrupt pending */
873 		switch (iir & 0x0f) {
874 		case SERIAL_IIR_RLS:
875 			dbg("Serial Port: Receiver status error or address "
876 			    "bit detected in 9-bit mode\n");
877 			break;
878 		case SERIAL_IIR_CTI:
879 			dbg("Serial Port: Receiver time out");
880 			break;
881 		case SERIAL_IIR_MS:
882 			/* dbg("Serial Port: Modem status change"); */
883 			break;
884 		}
885 	}
886 
887 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
888 	{       /* update local copy of DSR reg */
889 		struct usb_serial_port *port = urb->context;
890 		struct mos7715_parport *mos_parport = port->serial->private;
891 		if (unlikely(mos_parport == NULL))
892 			return;
893 		atomic_set(&mos_parport->shadowDSR, data[2]);
894 	}
895 #endif
896 
897 exit:
898 	result = usb_submit_urb(urb, GFP_ATOMIC);
899 	if (result)
900 		dev_err(&urb->dev->dev,
901 			"%s - Error %d submitting control urb\n",
902 			__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 	struct tty_struct *tty;
916 	int status = urb->status;
917 
918 	if (status) {
919 		dbg("nonzero read bulk status received: %d", status);
920 		return;
921 	}
922 
923 	port = urb->context;
924 
925 	dbg("Entering...%s", __func__);
926 
927 	data = urb->transfer_buffer;
928 
929 	tty = tty_port_tty_get(&port->port);
930 	if (tty && urb->actual_length) {
931 		tty_insert_flip_string(tty, data, urb->actual_length);
932 		tty_flip_buffer_push(tty);
933 	}
934 	tty_kref_put(tty);
935 
936 	if (port->read_urb->status != -EINPROGRESS) {
937 		retval = usb_submit_urb(port->read_urb, GFP_ATOMIC);
938 		if (retval)
939 			dbg("usb_submit_urb(read bulk) failed, retval = %d",
940 			    retval);
941 	}
942 }
943 
944 /*
945  * mos7720_bulk_out_data_callback
946  *	this is the callback function for when we have finished sending serial
947  *	data on the bulk out endpoint.
948  */
949 static void mos7720_bulk_out_data_callback(struct urb *urb)
950 {
951 	struct moschip_port *mos7720_port;
952 	struct tty_struct *tty;
953 	int status = urb->status;
954 
955 	if (status) {
956 		dbg("nonzero write bulk status received:%d", status);
957 		return;
958 	}
959 
960 	mos7720_port = urb->context;
961 	if (!mos7720_port) {
962 		dbg("NULL mos7720_port pointer");
963 		return ;
964 	}
965 
966 	tty = tty_port_tty_get(&mos7720_port->port->port);
967 
968 	if (tty && mos7720_port->open)
969 		tty_wakeup(tty);
970 	tty_kref_put(tty);
971 }
972 
973 /*
974  * mos77xx_probe
975  *	this function installs the appropriate read interrupt endpoint callback
976  *	depending on whether the device is a 7720 or 7715, thus avoiding costly
977  *	run-time checks in the high-frequency callback routine itself.
978  */
979 static int mos77xx_probe(struct usb_serial *serial,
980 			 const struct usb_device_id *id)
981 {
982 	if (id->idProduct == MOSCHIP_DEVICE_ID_7715)
983 		moschip7720_2port_driver.read_int_callback =
984 			mos7715_interrupt_callback;
985 	else
986 		moschip7720_2port_driver.read_int_callback =
987 			mos7720_interrupt_callback;
988 
989 	return 0;
990 }
991 
992 static int mos77xx_calc_num_ports(struct usb_serial *serial)
993 {
994 	u16 product = le16_to_cpu(serial->dev->descriptor.idProduct);
995 	if (product == MOSCHIP_DEVICE_ID_7715)
996 		return 1;
997 
998 	return 2;
999 }
1000 
1001 static int mos7720_open(struct tty_struct *tty, struct usb_serial_port *port)
1002 {
1003 	struct usb_serial *serial;
1004 	struct urb *urb;
1005 	struct moschip_port *mos7720_port;
1006 	int response;
1007 	int port_number;
1008 	__u8 data;
1009 	int allocated_urbs = 0;
1010 	int j;
1011 
1012 	serial = port->serial;
1013 
1014 	mos7720_port = usb_get_serial_port_data(port);
1015 	if (mos7720_port == NULL)
1016 		return -ENODEV;
1017 
1018 	usb_clear_halt(serial->dev, port->write_urb->pipe);
1019 	usb_clear_halt(serial->dev, port->read_urb->pipe);
1020 
1021 	/* Initialising the write urb pool */
1022 	for (j = 0; j < NUM_URBS; ++j) {
1023 		urb = usb_alloc_urb(0, GFP_KERNEL);
1024 		mos7720_port->write_urb_pool[j] = urb;
1025 
1026 		if (urb == NULL) {
1027 			dev_err(&port->dev, "No more urbs???\n");
1028 			continue;
1029 		}
1030 
1031 		urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE,
1032 					       GFP_KERNEL);
1033 		if (!urb->transfer_buffer) {
1034 			dev_err(&port->dev,
1035 				"%s-out of memory for urb buffers.\n",
1036 				__func__);
1037 			usb_free_urb(mos7720_port->write_urb_pool[j]);
1038 			mos7720_port->write_urb_pool[j] = NULL;
1039 			continue;
1040 		}
1041 		allocated_urbs++;
1042 	}
1043 
1044 	if (!allocated_urbs)
1045 		return -ENOMEM;
1046 
1047 	 /* Initialize MCS7720 -- Write Init values to corresponding Registers
1048 	  *
1049 	  * Register Index
1050 	  * 0 : THR/RHR
1051 	  * 1 : IER
1052 	  * 2 : FCR
1053 	  * 3 : LCR
1054 	  * 4 : MCR
1055 	  * 5 : LSR
1056 	  * 6 : MSR
1057 	  * 7 : SPR
1058 	  *
1059 	  * 0x08 : SP1/2 Control Reg
1060 	  */
1061 	port_number = port->number - port->serial->minor;
1062 	read_mos_reg(serial, port_number, LSR, &data);
1063 
1064 	dbg("SS::%p LSR:%x", mos7720_port, data);
1065 
1066 	dbg("Check:Sending Command ..........");
1067 
1068 	write_mos_reg(serial, dummy, SP1_REG, 0x02);
1069 	write_mos_reg(serial, dummy, SP2_REG, 0x02);
1070 
1071 	write_mos_reg(serial, port_number, IER, 0x00);
1072 	write_mos_reg(serial, port_number, FCR, 0x00);
1073 
1074 	write_mos_reg(serial, port_number, FCR, 0xcf);
1075 	mos7720_port->shadowLCR = 0x03;
1076 	write_mos_reg(serial, port_number, LCR, mos7720_port->shadowLCR);
1077 	mos7720_port->shadowMCR = 0x0b;
1078 	write_mos_reg(serial, port_number, MCR, mos7720_port->shadowMCR);
1079 
1080 	write_mos_reg(serial, port_number, SP_CONTROL_REG, 0x00);
1081 	read_mos_reg(serial, dummy, SP_CONTROL_REG, &data);
1082 	data = data | (port->number - port->serial->minor + 1);
1083 	write_mos_reg(serial, dummy, SP_CONTROL_REG, data);
1084 	mos7720_port->shadowLCR = 0x83;
1085 	write_mos_reg(serial, port_number, LCR, mos7720_port->shadowLCR);
1086 	write_mos_reg(serial, port_number, THR, 0x0c);
1087 	write_mos_reg(serial, port_number, IER, 0x00);
1088 	mos7720_port->shadowLCR = 0x03;
1089 	write_mos_reg(serial, port_number, LCR, mos7720_port->shadowLCR);
1090 	write_mos_reg(serial, port_number, IER, 0x0c);
1091 
1092 	response = usb_submit_urb(port->read_urb, GFP_KERNEL);
1093 	if (response)
1094 		dev_err(&port->dev, "%s - Error %d submitting read urb\n",
1095 							__func__, response);
1096 
1097 	/* initialize our icount structure */
1098 	memset(&(mos7720_port->icount), 0x00, sizeof(mos7720_port->icount));
1099 
1100 	/* initialize our port settings */
1101 	mos7720_port->shadowMCR = UART_MCR_OUT2; /* Must set to enable ints! */
1102 
1103 	/* send a open port command */
1104 	mos7720_port->open = 1;
1105 
1106 	return 0;
1107 }
1108 
1109 /*
1110  * mos7720_chars_in_buffer
1111  *	this function is called by the tty driver when it wants to know how many
1112  *	bytes of data we currently have outstanding in the port (data that has
1113  *	been written, but hasn't made it out the port yet)
1114  *	If successful, we return the number of bytes left to be written in the
1115  *	system,
1116  *	Otherwise we return a negative error number.
1117  */
1118 static int mos7720_chars_in_buffer(struct tty_struct *tty)
1119 {
1120 	struct usb_serial_port *port = tty->driver_data;
1121 	int i;
1122 	int chars = 0;
1123 	struct moschip_port *mos7720_port;
1124 
1125 	dbg("%s:entering ...........", __func__);
1126 
1127 	mos7720_port = usb_get_serial_port_data(port);
1128 	if (mos7720_port == NULL) {
1129 		dbg("%s:leaving ...........", __func__);
1130 		return 0;
1131 	}
1132 
1133 	for (i = 0; i < NUM_URBS; ++i) {
1134 		if (mos7720_port->write_urb_pool[i] &&
1135 		    mos7720_port->write_urb_pool[i]->status == -EINPROGRESS)
1136 			chars += URB_TRANSFER_BUFFER_SIZE;
1137 	}
1138 	dbg("%s - returns %d", __func__, chars);
1139 	return chars;
1140 }
1141 
1142 static void mos7720_close(struct usb_serial_port *port)
1143 {
1144 	struct usb_serial *serial;
1145 	struct moschip_port *mos7720_port;
1146 	int j;
1147 
1148 	dbg("mos7720_close:entering...");
1149 
1150 	serial = port->serial;
1151 
1152 	mos7720_port = usb_get_serial_port_data(port);
1153 	if (mos7720_port == NULL)
1154 		return;
1155 
1156 	for (j = 0; j < NUM_URBS; ++j)
1157 		usb_kill_urb(mos7720_port->write_urb_pool[j]);
1158 
1159 	/* Freeing Write URBs */
1160 	for (j = 0; j < NUM_URBS; ++j) {
1161 		if (mos7720_port->write_urb_pool[j]) {
1162 			kfree(mos7720_port->write_urb_pool[j]->transfer_buffer);
1163 			usb_free_urb(mos7720_port->write_urb_pool[j]);
1164 		}
1165 	}
1166 
1167 	/* While closing port, shutdown all bulk read, write  *
1168 	 * and interrupt read if they exists, otherwise nop   */
1169 	dbg("Shutdown bulk write");
1170 	usb_kill_urb(port->write_urb);
1171 	dbg("Shutdown bulk read");
1172 	usb_kill_urb(port->read_urb);
1173 
1174 	mutex_lock(&serial->disc_mutex);
1175 	/* these commands must not be issued if the device has
1176 	 * been disconnected */
1177 	if (!serial->disconnected) {
1178 		write_mos_reg(serial, port->number - port->serial->minor,
1179 			      MCR, 0x00);
1180 		write_mos_reg(serial, port->number - port->serial->minor,
1181 			      IER, 0x00);
1182 	}
1183 	mutex_unlock(&serial->disc_mutex);
1184 	mos7720_port->open = 0;
1185 
1186 	dbg("Leaving %s", __func__);
1187 }
1188 
1189 static void mos7720_break(struct tty_struct *tty, int break_state)
1190 {
1191 	struct usb_serial_port *port = tty->driver_data;
1192 	unsigned char data;
1193 	struct usb_serial *serial;
1194 	struct moschip_port *mos7720_port;
1195 
1196 	dbg("Entering %s", __func__);
1197 
1198 	serial = port->serial;
1199 
1200 	mos7720_port = usb_get_serial_port_data(port);
1201 	if (mos7720_port == NULL)
1202 		return;
1203 
1204 	if (break_state == -1)
1205 		data = mos7720_port->shadowLCR | UART_LCR_SBC;
1206 	else
1207 		data = mos7720_port->shadowLCR & ~UART_LCR_SBC;
1208 
1209 	mos7720_port->shadowLCR  = data;
1210 	write_mos_reg(serial, port->number - port->serial->minor,
1211 		      LCR, mos7720_port->shadowLCR);
1212 }
1213 
1214 /*
1215  * mos7720_write_room
1216  *	this function is called by the tty driver when it wants to know how many
1217  *	bytes of data we can accept for a specific port.
1218  *	If successful, we return the amount of room that we have for this port
1219  *	Otherwise we return a negative error number.
1220  */
1221 static int mos7720_write_room(struct tty_struct *tty)
1222 {
1223 	struct usb_serial_port *port = tty->driver_data;
1224 	struct moschip_port *mos7720_port;
1225 	int room = 0;
1226 	int i;
1227 
1228 	dbg("%s:entering ...........", __func__);
1229 
1230 	mos7720_port = usb_get_serial_port_data(port);
1231 	if (mos7720_port == NULL) {
1232 		dbg("%s:leaving ...........", __func__);
1233 		return -ENODEV;
1234 	}
1235 
1236 	/* FIXME: Locking */
1237 	for (i = 0; i < NUM_URBS; ++i) {
1238 		if (mos7720_port->write_urb_pool[i] &&
1239 		    mos7720_port->write_urb_pool[i]->status != -EINPROGRESS)
1240 			room += URB_TRANSFER_BUFFER_SIZE;
1241 	}
1242 
1243 	dbg("%s - returns %d", __func__, room);
1244 	return room;
1245 }
1246 
1247 static int mos7720_write(struct tty_struct *tty, struct usb_serial_port *port,
1248 				 const unsigned char *data, int count)
1249 {
1250 	int status;
1251 	int i;
1252 	int bytes_sent = 0;
1253 	int transfer_size;
1254 
1255 	struct moschip_port *mos7720_port;
1256 	struct usb_serial *serial;
1257 	struct urb    *urb;
1258 	const unsigned char *current_position = data;
1259 
1260 	dbg("%s:entering ...........", __func__);
1261 
1262 	serial = port->serial;
1263 
1264 	mos7720_port = usb_get_serial_port_data(port);
1265 	if (mos7720_port == NULL) {
1266 		dbg("mos7720_port is NULL");
1267 		return -ENODEV;
1268 	}
1269 
1270 	/* try to find a free urb in the list */
1271 	urb = NULL;
1272 
1273 	for (i = 0; i < NUM_URBS; ++i) {
1274 		if (mos7720_port->write_urb_pool[i] &&
1275 		    mos7720_port->write_urb_pool[i]->status != -EINPROGRESS) {
1276 			urb = mos7720_port->write_urb_pool[i];
1277 			dbg("URB:%d", i);
1278 			break;
1279 		}
1280 	}
1281 
1282 	if (urb == NULL) {
1283 		dbg("%s - no more free urbs", __func__);
1284 		goto exit;
1285 	}
1286 
1287 	if (urb->transfer_buffer == NULL) {
1288 		urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE,
1289 					       GFP_KERNEL);
1290 		if (urb->transfer_buffer == NULL) {
1291 			dev_err_console(port, "%s no more kernel memory...\n",
1292 				__func__);
1293 			goto exit;
1294 		}
1295 	}
1296 	transfer_size = min(count, URB_TRANSFER_BUFFER_SIZE);
1297 
1298 	memcpy(urb->transfer_buffer, current_position, transfer_size);
1299 	usb_serial_debug_data(debug, &port->dev, __func__, transfer_size,
1300 			      urb->transfer_buffer);
1301 
1302 	/* fill urb with data and submit  */
1303 	usb_fill_bulk_urb(urb, serial->dev,
1304 			  usb_sndbulkpipe(serial->dev,
1305 					port->bulk_out_endpointAddress),
1306 			  urb->transfer_buffer, transfer_size,
1307 			  mos7720_bulk_out_data_callback, mos7720_port);
1308 
1309 	/* send it down the pipe */
1310 	status = usb_submit_urb(urb, GFP_ATOMIC);
1311 	if (status) {
1312 		dev_err_console(port, "%s - usb_submit_urb(write bulk) failed "
1313 			"with status = %d\n", __func__, status);
1314 		bytes_sent = status;
1315 		goto exit;
1316 	}
1317 	bytes_sent = transfer_size;
1318 
1319 exit:
1320 	return bytes_sent;
1321 }
1322 
1323 static void mos7720_throttle(struct tty_struct *tty)
1324 {
1325 	struct usb_serial_port *port = tty->driver_data;
1326 	struct moschip_port *mos7720_port;
1327 	int status;
1328 
1329 	dbg("%s- port %d", __func__, port->number);
1330 
1331 	mos7720_port = usb_get_serial_port_data(port);
1332 
1333 	if (mos7720_port == NULL)
1334 		return;
1335 
1336 	if (!mos7720_port->open) {
1337 		dbg("port not opened");
1338 		return;
1339 	}
1340 
1341 	dbg("%s: Entering ..........", __func__);
1342 
1343 	/* if we are implementing XON/XOFF, send the stop character */
1344 	if (I_IXOFF(tty)) {
1345 		unsigned char stop_char = STOP_CHAR(tty);
1346 		status = mos7720_write(tty, port, &stop_char, 1);
1347 		if (status <= 0)
1348 			return;
1349 	}
1350 
1351 	/* if we are implementing RTS/CTS, toggle that line */
1352 	if (tty->termios->c_cflag & CRTSCTS) {
1353 		mos7720_port->shadowMCR &= ~UART_MCR_RTS;
1354 		write_mos_reg(port->serial, port->number - port->serial->minor,
1355 			      MCR, mos7720_port->shadowMCR);
1356 		if (status != 0)
1357 			return;
1358 	}
1359 }
1360 
1361 static void mos7720_unthrottle(struct tty_struct *tty)
1362 {
1363 	struct usb_serial_port *port = tty->driver_data;
1364 	struct moschip_port *mos7720_port = usb_get_serial_port_data(port);
1365 	int status;
1366 
1367 	if (mos7720_port == NULL)
1368 		return;
1369 
1370 	if (!mos7720_port->open) {
1371 		dbg("%s - port not opened", __func__);
1372 		return;
1373 	}
1374 
1375 	dbg("%s: Entering ..........", __func__);
1376 
1377 	/* if we are implementing XON/XOFF, send the start character */
1378 	if (I_IXOFF(tty)) {
1379 		unsigned char start_char = START_CHAR(tty);
1380 		status = mos7720_write(tty, port, &start_char, 1);
1381 		if (status <= 0)
1382 			return;
1383 	}
1384 
1385 	/* if we are implementing RTS/CTS, toggle that line */
1386 	if (tty->termios->c_cflag & CRTSCTS) {
1387 		mos7720_port->shadowMCR |= UART_MCR_RTS;
1388 		write_mos_reg(port->serial, port->number - port->serial->minor,
1389 			      MCR, mos7720_port->shadowMCR);
1390 		if (status != 0)
1391 			return;
1392 	}
1393 }
1394 
1395 /* FIXME: this function does not work */
1396 static int set_higher_rates(struct moschip_port *mos7720_port,
1397 			    unsigned int baud)
1398 {
1399 	struct usb_serial_port *port;
1400 	struct usb_serial *serial;
1401 	int port_number;
1402 	enum mos_regs sp_reg;
1403 	if (mos7720_port == NULL)
1404 		return -EINVAL;
1405 
1406 	port = mos7720_port->port;
1407 	serial = port->serial;
1408 
1409 	 /***********************************************
1410 	 *      Init Sequence for higher rates
1411 	 ***********************************************/
1412 	dbg("Sending Setting Commands ..........");
1413 	port_number = port->number - port->serial->minor;
1414 
1415 	write_mos_reg(serial, port_number, IER, 0x00);
1416 	write_mos_reg(serial, port_number, FCR, 0x00);
1417 	write_mos_reg(serial, port_number, FCR, 0xcf);
1418 	mos7720_port->shadowMCR = 0x0b;
1419 	write_mos_reg(serial, port_number, MCR, mos7720_port->shadowMCR);
1420 	write_mos_reg(serial, dummy, SP_CONTROL_REG, 0x00);
1421 
1422 	/***********************************************
1423 	 *              Set for higher rates           *
1424 	 ***********************************************/
1425 	/* writing baud rate verbatum into uart clock field clearly not right */
1426 	if (port_number == 0)
1427 		sp_reg = SP1_REG;
1428 	else
1429 		sp_reg = SP2_REG;
1430 	write_mos_reg(serial, dummy, sp_reg, baud * 0x10);
1431 	write_mos_reg(serial, dummy, SP_CONTROL_REG, 0x03);
1432 	mos7720_port->shadowMCR = 0x2b;
1433 	write_mos_reg(serial, port_number, MCR, mos7720_port->shadowMCR);
1434 
1435 	/***********************************************
1436 	 *              Set DLL/DLM
1437 	 ***********************************************/
1438 	mos7720_port->shadowLCR = mos7720_port->shadowLCR | UART_LCR_DLAB;
1439 	write_mos_reg(serial, port_number, LCR, mos7720_port->shadowLCR);
1440 	write_mos_reg(serial, port_number, DLL, 0x01);
1441 	write_mos_reg(serial, port_number, DLM, 0x00);
1442 	mos7720_port->shadowLCR = mos7720_port->shadowLCR & ~UART_LCR_DLAB;
1443 	write_mos_reg(serial, port_number, LCR, mos7720_port->shadowLCR);
1444 
1445 	return 0;
1446 }
1447 
1448 /* baud rate information */
1449 struct divisor_table_entry {
1450 	__u32  baudrate;
1451 	__u16  divisor;
1452 };
1453 
1454 /* Define table of divisors for moschip 7720 hardware	   *
1455  * These assume a 3.6864MHz crystal, the standard /16, and *
1456  * MCR.7 = 0.						   */
1457 static struct divisor_table_entry divisor_table[] = {
1458 	{   50,		2304},
1459 	{   110,	1047},	/* 2094.545455 => 230450   => .0217 % over */
1460 	{   134,	857},	/* 1713.011152 => 230398.5 => .00065% under */
1461 	{   150,	768},
1462 	{   300,	384},
1463 	{   600,	192},
1464 	{   1200,	96},
1465 	{   1800,	64},
1466 	{   2400,	48},
1467 	{   4800,	24},
1468 	{   7200,	16},
1469 	{   9600,	12},
1470 	{   19200,	6},
1471 	{   38400,	3},
1472 	{   57600,	2},
1473 	{   115200,	1},
1474 };
1475 
1476 /*****************************************************************************
1477  * calc_baud_rate_divisor
1478  *	this function calculates the proper baud rate divisor for the specified
1479  *	baud rate.
1480  *****************************************************************************/
1481 static int calc_baud_rate_divisor(int baudrate, int *divisor)
1482 {
1483 	int i;
1484 	__u16 custom;
1485 	__u16 round1;
1486 	__u16 round;
1487 
1488 
1489 	dbg("%s - %d", __func__, baudrate);
1490 
1491 	for (i = 0; i < ARRAY_SIZE(divisor_table); i++) {
1492 		if (divisor_table[i].baudrate == baudrate) {
1493 			*divisor = divisor_table[i].divisor;
1494 			return 0;
1495 		}
1496 	}
1497 
1498 	/* After trying for all the standard baud rates    *
1499 	 * Try calculating the divisor for this baud rate  */
1500 	if (baudrate > 75 &&  baudrate < 230400) {
1501 		/* get the divisor */
1502 		custom = (__u16)(230400L  / baudrate);
1503 
1504 		/* Check for round off */
1505 		round1 = (__u16)(2304000L / baudrate);
1506 		round = (__u16)(round1 - (custom * 10));
1507 		if (round > 4)
1508 			custom++;
1509 		*divisor = custom;
1510 
1511 		dbg("Baud %d = %d", baudrate, custom);
1512 		return 0;
1513 	}
1514 
1515 	dbg("Baud calculation Failed...");
1516 	return -EINVAL;
1517 }
1518 
1519 /*
1520  * send_cmd_write_baud_rate
1521  *	this function sends the proper command to change the baud rate of the
1522  *	specified port.
1523  */
1524 static int send_cmd_write_baud_rate(struct moschip_port *mos7720_port,
1525 				    int baudrate)
1526 {
1527 	struct usb_serial_port *port;
1528 	struct usb_serial *serial;
1529 	int divisor;
1530 	int status;
1531 	unsigned char number;
1532 
1533 	if (mos7720_port == NULL)
1534 		return -1;
1535 
1536 	port = mos7720_port->port;
1537 	serial = port->serial;
1538 
1539 	dbg("%s: Entering ..........", __func__);
1540 
1541 	number = port->number - port->serial->minor;
1542 	dbg("%s - port = %d, baud = %d", __func__, port->number, baudrate);
1543 
1544 	/* Calculate the Divisor */
1545 	status = calc_baud_rate_divisor(baudrate, &divisor);
1546 	if (status) {
1547 		dev_err(&port->dev, "%s - bad baud rate\n", __func__);
1548 		return status;
1549 	}
1550 
1551 	/* Enable access to divisor latch */
1552 	mos7720_port->shadowLCR = mos7720_port->shadowLCR | UART_LCR_DLAB;
1553 	write_mos_reg(serial, number, LCR, mos7720_port->shadowLCR);
1554 
1555 	/* Write the divisor */
1556 	write_mos_reg(serial, number, DLL, (__u8)(divisor & 0xff));
1557 	write_mos_reg(serial, number, DLM, (__u8)((divisor & 0xff00) >> 8));
1558 
1559 	/* Disable access to divisor latch */
1560 	mos7720_port->shadowLCR = mos7720_port->shadowLCR & ~UART_LCR_DLAB;
1561 	write_mos_reg(serial, number, LCR, mos7720_port->shadowLCR);
1562 
1563 	return status;
1564 }
1565 
1566 /*
1567  * change_port_settings
1568  *	This routine is called to set the UART on the device to match
1569  *      the specified new settings.
1570  */
1571 static void change_port_settings(struct tty_struct *tty,
1572 				 struct moschip_port *mos7720_port,
1573 				 struct ktermios *old_termios)
1574 {
1575 	struct usb_serial_port *port;
1576 	struct usb_serial *serial;
1577 	int baud;
1578 	unsigned cflag;
1579 	unsigned iflag;
1580 	__u8 mask = 0xff;
1581 	__u8 lData;
1582 	__u8 lParity;
1583 	__u8 lStop;
1584 	int status;
1585 	int port_number;
1586 
1587 	if (mos7720_port == NULL)
1588 		return ;
1589 
1590 	port = mos7720_port->port;
1591 	serial = port->serial;
1592 	port_number = port->number - port->serial->minor;
1593 
1594 	dbg("%s - port %d", __func__, port->number);
1595 
1596 	if (!mos7720_port->open) {
1597 		dbg("%s - port not opened", __func__);
1598 		return;
1599 	}
1600 
1601 	dbg("%s: Entering ..........", __func__);
1602 
1603 	lData = UART_LCR_WLEN8;
1604 	lStop = 0x00;	/* 1 stop bit */
1605 	lParity = 0x00;	/* No parity */
1606 
1607 	cflag = tty->termios->c_cflag;
1608 	iflag = tty->termios->c_iflag;
1609 
1610 	/* Change the number of bits */
1611 	switch (cflag & CSIZE) {
1612 	case CS5:
1613 		lData = UART_LCR_WLEN5;
1614 		mask = 0x1f;
1615 		break;
1616 
1617 	case CS6:
1618 		lData = UART_LCR_WLEN6;
1619 		mask = 0x3f;
1620 		break;
1621 
1622 	case CS7:
1623 		lData = UART_LCR_WLEN7;
1624 		mask = 0x7f;
1625 		break;
1626 	default:
1627 	case CS8:
1628 		lData = UART_LCR_WLEN8;
1629 		break;
1630 	}
1631 
1632 	/* Change the Parity bit */
1633 	if (cflag & PARENB) {
1634 		if (cflag & PARODD) {
1635 			lParity = UART_LCR_PARITY;
1636 			dbg("%s - parity = odd", __func__);
1637 		} else {
1638 			lParity = (UART_LCR_EPAR | UART_LCR_PARITY);
1639 			dbg("%s - parity = even", __func__);
1640 		}
1641 
1642 	} else {
1643 		dbg("%s - parity = none", __func__);
1644 	}
1645 
1646 	if (cflag & CMSPAR)
1647 		lParity = lParity | 0x20;
1648 
1649 	/* Change the Stop bit */
1650 	if (cflag & CSTOPB) {
1651 		lStop = UART_LCR_STOP;
1652 		dbg("%s - stop bits = 2", __func__);
1653 	} else {
1654 		lStop = 0x00;
1655 		dbg("%s - stop bits = 1", __func__);
1656 	}
1657 
1658 #define LCR_BITS_MASK		0x03	/* Mask for bits/char field */
1659 #define LCR_STOP_MASK		0x04	/* Mask for stop bits field */
1660 #define LCR_PAR_MASK		0x38	/* Mask for parity field */
1661 
1662 	/* Update the LCR with the correct value */
1663 	mos7720_port->shadowLCR &=
1664 		~(LCR_BITS_MASK | LCR_STOP_MASK | LCR_PAR_MASK);
1665 	mos7720_port->shadowLCR |= (lData | lParity | lStop);
1666 
1667 
1668 	/* Disable Interrupts */
1669 	write_mos_reg(serial, port_number, IER, 0x00);
1670 	write_mos_reg(serial, port_number, FCR, 0x00);
1671 	write_mos_reg(serial, port_number, FCR, 0xcf);
1672 
1673 	/* Send the updated LCR value to the mos7720 */
1674 	write_mos_reg(serial, port_number, LCR, mos7720_port->shadowLCR);
1675 	mos7720_port->shadowMCR = 0x0b;
1676 	write_mos_reg(serial, port_number, MCR, mos7720_port->shadowMCR);
1677 
1678 	/* set up the MCR register and send it to the mos7720 */
1679 	mos7720_port->shadowMCR = UART_MCR_OUT2;
1680 	if (cflag & CBAUD)
1681 		mos7720_port->shadowMCR |= (UART_MCR_DTR | UART_MCR_RTS);
1682 
1683 	if (cflag & CRTSCTS) {
1684 		mos7720_port->shadowMCR |= (UART_MCR_XONANY);
1685 		/* To set hardware flow control to the specified *
1686 		 * serial port, in SP1/2_CONTROL_REG             */
1687 		if (port->number)
1688 			write_mos_reg(serial, dummy, SP_CONTROL_REG, 0x01);
1689 		else
1690 			write_mos_reg(serial, dummy, SP_CONTROL_REG, 0x02);
1691 
1692 	} else
1693 		mos7720_port->shadowMCR &= ~(UART_MCR_XONANY);
1694 
1695 	write_mos_reg(serial, port_number, MCR, mos7720_port->shadowMCR);
1696 
1697 	/* Determine divisor based on baud rate */
1698 	baud = tty_get_baud_rate(tty);
1699 	if (!baud) {
1700 		/* pick a default, any default... */
1701 		dbg("Picked default baud...");
1702 		baud = 9600;
1703 	}
1704 
1705 	if (baud >= 230400) {
1706 		set_higher_rates(mos7720_port, baud);
1707 		/* Enable Interrupts */
1708 		write_mos_reg(serial, port_number, IER, 0x0c);
1709 		return;
1710 	}
1711 
1712 	dbg("%s - baud rate = %d", __func__, baud);
1713 	status = send_cmd_write_baud_rate(mos7720_port, baud);
1714 	/* FIXME: needs to write actual resulting baud back not just
1715 	   blindly do so */
1716 	if (cflag & CBAUD)
1717 		tty_encode_baud_rate(tty, baud, baud);
1718 	/* Enable Interrupts */
1719 	write_mos_reg(serial, port_number, IER, 0x0c);
1720 
1721 	if (port->read_urb->status != -EINPROGRESS) {
1722 		status = usb_submit_urb(port->read_urb, GFP_ATOMIC);
1723 		if (status)
1724 			dbg("usb_submit_urb(read bulk) failed, status = %d",
1725 			    status);
1726 	}
1727 }
1728 
1729 /*
1730  * mos7720_set_termios
1731  *	this function is called by the tty driver when it wants to change the
1732  *	termios structure.
1733  */
1734 static void mos7720_set_termios(struct tty_struct *tty,
1735 		struct usb_serial_port *port, struct ktermios *old_termios)
1736 {
1737 	int status;
1738 	unsigned int cflag;
1739 	struct usb_serial *serial;
1740 	struct moschip_port *mos7720_port;
1741 
1742 	serial = port->serial;
1743 
1744 	mos7720_port = usb_get_serial_port_data(port);
1745 
1746 	if (mos7720_port == NULL)
1747 		return;
1748 
1749 	if (!mos7720_port->open) {
1750 		dbg("%s - port not opened", __func__);
1751 		return;
1752 	}
1753 
1754 	dbg("%s\n", "setting termios - ASPIRE");
1755 
1756 	cflag = tty->termios->c_cflag;
1757 
1758 	dbg("%s - cflag %08x iflag %08x", __func__,
1759 	    tty->termios->c_cflag,
1760 	    RELEVANT_IFLAG(tty->termios->c_iflag));
1761 
1762 	dbg("%s - old cflag %08x old iflag %08x", __func__,
1763 	    old_termios->c_cflag,
1764 	    RELEVANT_IFLAG(old_termios->c_iflag));
1765 
1766 	dbg("%s - port %d", __func__, port->number);
1767 
1768 	/* change the port settings to the new ones specified */
1769 	change_port_settings(tty, mos7720_port, old_termios);
1770 
1771 	if (port->read_urb->status != -EINPROGRESS) {
1772 		status = usb_submit_urb(port->read_urb, GFP_ATOMIC);
1773 		if (status)
1774 			dbg("usb_submit_urb(read bulk) failed, status = %d",
1775 			    status);
1776 	}
1777 }
1778 
1779 /*
1780  * get_lsr_info - get line status register info
1781  *
1782  * Purpose: Let user call ioctl() to get info when the UART physically
1783  * 	    is emptied.  On bus types like RS485, the transmitter must
1784  * 	    release the bus after transmitting. This must be done when
1785  * 	    the transmit shift register is empty, not be done when the
1786  * 	    transmit holding register is empty.  This functionality
1787  * 	    allows an RS485 driver to be written in user space.
1788  */
1789 static int get_lsr_info(struct tty_struct *tty,
1790 		struct moschip_port *mos7720_port, unsigned int __user *value)
1791 {
1792 	struct usb_serial_port *port = tty->driver_data;
1793 	unsigned int result = 0;
1794 	unsigned char data = 0;
1795 	int port_number = port->number - port->serial->minor;
1796 	int count;
1797 
1798 	count = mos7720_chars_in_buffer(tty);
1799 	if (count == 0) {
1800 		read_mos_reg(port->serial, port_number, LSR, &data);
1801 		if ((data & (UART_LSR_TEMT | UART_LSR_THRE))
1802 					== (UART_LSR_TEMT | UART_LSR_THRE)) {
1803 			dbg("%s -- Empty", __func__);
1804 			result = TIOCSER_TEMT;
1805 		}
1806 	}
1807 	if (copy_to_user(value, &result, sizeof(int)))
1808 		return -EFAULT;
1809 	return 0;
1810 }
1811 
1812 static int mos7720_tiocmget(struct tty_struct *tty)
1813 {
1814 	struct usb_serial_port *port = tty->driver_data;
1815 	struct moschip_port *mos7720_port = usb_get_serial_port_data(port);
1816 	unsigned int result = 0;
1817 	unsigned int mcr ;
1818 	unsigned int msr ;
1819 
1820 	dbg("%s - port %d", __func__, port->number);
1821 
1822 	mcr = mos7720_port->shadowMCR;
1823 	msr = mos7720_port->shadowMSR;
1824 
1825 	result = ((mcr & UART_MCR_DTR)  ? TIOCM_DTR : 0)   /* 0x002 */
1826 	  | ((mcr & UART_MCR_RTS)   ? TIOCM_RTS : 0)   /* 0x004 */
1827 	  | ((msr & UART_MSR_CTS)   ? TIOCM_CTS : 0)   /* 0x020 */
1828 	  | ((msr & UART_MSR_DCD)   ? TIOCM_CAR : 0)   /* 0x040 */
1829 	  | ((msr & UART_MSR_RI)    ? TIOCM_RI :  0)   /* 0x080 */
1830 	  | ((msr & UART_MSR_DSR)   ? TIOCM_DSR : 0);  /* 0x100 */
1831 
1832 	dbg("%s -- %x", __func__, result);
1833 
1834 	return result;
1835 }
1836 
1837 static int mos7720_tiocmset(struct tty_struct *tty,
1838 			    unsigned int set, unsigned int clear)
1839 {
1840 	struct usb_serial_port *port = tty->driver_data;
1841 	struct moschip_port *mos7720_port = usb_get_serial_port_data(port);
1842 	unsigned int mcr ;
1843 	dbg("%s - port %d", __func__, port->number);
1844 	dbg("he was at tiocmset");
1845 
1846 	mcr = mos7720_port->shadowMCR;
1847 
1848 	if (set & TIOCM_RTS)
1849 		mcr |= UART_MCR_RTS;
1850 	if (set & TIOCM_DTR)
1851 		mcr |= UART_MCR_DTR;
1852 	if (set & TIOCM_LOOP)
1853 		mcr |= UART_MCR_LOOP;
1854 
1855 	if (clear & TIOCM_RTS)
1856 		mcr &= ~UART_MCR_RTS;
1857 	if (clear & TIOCM_DTR)
1858 		mcr &= ~UART_MCR_DTR;
1859 	if (clear & TIOCM_LOOP)
1860 		mcr &= ~UART_MCR_LOOP;
1861 
1862 	mos7720_port->shadowMCR = mcr;
1863 	write_mos_reg(port->serial, port->number - port->serial->minor,
1864 		      MCR, mos7720_port->shadowMCR);
1865 
1866 	return 0;
1867 }
1868 
1869 static int mos7720_get_icount(struct tty_struct *tty,
1870 				struct serial_icounter_struct *icount)
1871 {
1872 	struct usb_serial_port *port = tty->driver_data;
1873 	struct moschip_port *mos7720_port;
1874 	struct async_icount cnow;
1875 
1876 	mos7720_port = usb_get_serial_port_data(port);
1877 	cnow = mos7720_port->icount;
1878 
1879 	icount->cts = cnow.cts;
1880 	icount->dsr = cnow.dsr;
1881 	icount->rng = cnow.rng;
1882 	icount->dcd = cnow.dcd;
1883 	icount->rx = cnow.rx;
1884 	icount->tx = cnow.tx;
1885 	icount->frame = cnow.frame;
1886 	icount->overrun = cnow.overrun;
1887 	icount->parity = cnow.parity;
1888 	icount->brk = cnow.brk;
1889 	icount->buf_overrun = cnow.buf_overrun;
1890 
1891 	dbg("%s (%d) TIOCGICOUNT RX=%d, TX=%d", __func__,
1892 		port->number, icount->rx, icount->tx);
1893 	return 0;
1894 }
1895 
1896 static int set_modem_info(struct moschip_port *mos7720_port, unsigned int cmd,
1897 			  unsigned int __user *value)
1898 {
1899 	unsigned int mcr;
1900 	unsigned int arg;
1901 
1902 	struct usb_serial_port *port;
1903 
1904 	if (mos7720_port == NULL)
1905 		return -1;
1906 
1907 	port = (struct usb_serial_port *)mos7720_port->port;
1908 	mcr = mos7720_port->shadowMCR;
1909 
1910 	if (copy_from_user(&arg, value, sizeof(int)))
1911 		return -EFAULT;
1912 
1913 	switch (cmd) {
1914 	case TIOCMBIS:
1915 		if (arg & TIOCM_RTS)
1916 			mcr |= UART_MCR_RTS;
1917 		if (arg & TIOCM_DTR)
1918 			mcr |= UART_MCR_RTS;
1919 		if (arg & TIOCM_LOOP)
1920 			mcr |= UART_MCR_LOOP;
1921 		break;
1922 
1923 	case TIOCMBIC:
1924 		if (arg & TIOCM_RTS)
1925 			mcr &= ~UART_MCR_RTS;
1926 		if (arg & TIOCM_DTR)
1927 			mcr &= ~UART_MCR_RTS;
1928 		if (arg & TIOCM_LOOP)
1929 			mcr &= ~UART_MCR_LOOP;
1930 		break;
1931 
1932 	}
1933 
1934 	mos7720_port->shadowMCR = mcr;
1935 	write_mos_reg(port->serial, port->number - port->serial->minor,
1936 		      MCR, mos7720_port->shadowMCR);
1937 
1938 	return 0;
1939 }
1940 
1941 static int get_serial_info(struct moschip_port *mos7720_port,
1942 			   struct serial_struct __user *retinfo)
1943 {
1944 	struct serial_struct tmp;
1945 
1946 	if (!retinfo)
1947 		return -EFAULT;
1948 
1949 	memset(&tmp, 0, sizeof(tmp));
1950 
1951 	tmp.type		= PORT_16550A;
1952 	tmp.line		= mos7720_port->port->serial->minor;
1953 	tmp.port		= mos7720_port->port->number;
1954 	tmp.irq			= 0;
1955 	tmp.flags		= ASYNC_SKIP_TEST | ASYNC_AUTO_IRQ;
1956 	tmp.xmit_fifo_size	= NUM_URBS * URB_TRANSFER_BUFFER_SIZE;
1957 	tmp.baud_base		= 9600;
1958 	tmp.close_delay		= 5*HZ;
1959 	tmp.closing_wait	= 30*HZ;
1960 
1961 	if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
1962 		return -EFAULT;
1963 	return 0;
1964 }
1965 
1966 static int mos7720_ioctl(struct tty_struct *tty,
1967 			 unsigned int cmd, unsigned long arg)
1968 {
1969 	struct usb_serial_port *port = tty->driver_data;
1970 	struct moschip_port *mos7720_port;
1971 	struct async_icount cnow;
1972 	struct async_icount cprev;
1973 
1974 	mos7720_port = usb_get_serial_port_data(port);
1975 	if (mos7720_port == NULL)
1976 		return -ENODEV;
1977 
1978 	dbg("%s - port %d, cmd = 0x%x", __func__, port->number, cmd);
1979 
1980 	switch (cmd) {
1981 	case TIOCSERGETLSR:
1982 		dbg("%s (%d) TIOCSERGETLSR", __func__,  port->number);
1983 		return get_lsr_info(tty, mos7720_port,
1984 					(unsigned int __user *)arg);
1985 
1986 	/* FIXME: These should be using the mode methods */
1987 	case TIOCMBIS:
1988 	case TIOCMBIC:
1989 		dbg("%s (%d) TIOCMSET/TIOCMBIC/TIOCMSET",
1990 					__func__, port->number);
1991 		return set_modem_info(mos7720_port, cmd,
1992 				      (unsigned int __user *)arg);
1993 
1994 	case TIOCGSERIAL:
1995 		dbg("%s (%d) TIOCGSERIAL", __func__,  port->number);
1996 		return get_serial_info(mos7720_port,
1997 				       (struct serial_struct __user *)arg);
1998 
1999 	case TIOCMIWAIT:
2000 		dbg("%s (%d) TIOCMIWAIT", __func__,  port->number);
2001 		cprev = mos7720_port->icount;
2002 		while (1) {
2003 			if (signal_pending(current))
2004 				return -ERESTARTSYS;
2005 			cnow = mos7720_port->icount;
2006 			if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
2007 			    cnow.dcd == cprev.dcd && cnow.cts == cprev.cts)
2008 				return -EIO; /* no change => error */
2009 			if (((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) ||
2010 			    ((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) ||
2011 			    ((arg & TIOCM_CD)  && (cnow.dcd != cprev.dcd)) ||
2012 			    ((arg & TIOCM_CTS) && (cnow.cts != cprev.cts))) {
2013 				return 0;
2014 			}
2015 			cprev = cnow;
2016 		}
2017 		/* NOTREACHED */
2018 		break;
2019 	}
2020 
2021 	return -ENOIOCTLCMD;
2022 }
2023 
2024 static int mos7720_startup(struct usb_serial *serial)
2025 {
2026 	struct moschip_port *mos7720_port;
2027 	struct usb_device *dev;
2028 	int i;
2029 	char data;
2030 	u16 product;
2031 	int ret_val;
2032 
2033 	dbg("%s: Entering ..........", __func__);
2034 
2035 	if (!serial) {
2036 		dbg("Invalid Handler");
2037 		return -ENODEV;
2038 	}
2039 
2040 	product = le16_to_cpu(serial->dev->descriptor.idProduct);
2041 	dev = serial->dev;
2042 
2043 	/*
2044 	 * The 7715 uses the first bulk in/out endpoint pair for the parallel
2045 	 * port, and the second for the serial port.  Because the usbserial core
2046 	 * assumes both pairs are serial ports, we must engage in a bit of
2047 	 * subterfuge and swap the pointers for ports 0 and 1 in order to make
2048 	 * port 0 point to the serial port.  However, both moschip devices use a
2049 	 * single interrupt-in endpoint for both ports (as mentioned a little
2050 	 * further down), and this endpoint was assigned to port 0.  So after
2051 	 * the swap, we must copy the interrupt endpoint elements from port 1
2052 	 * (as newly assigned) to port 0, and null out port 1 pointers.
2053 	 */
2054 	if (product == MOSCHIP_DEVICE_ID_7715) {
2055 		struct usb_serial_port *tmp = serial->port[0];
2056 		serial->port[0] = serial->port[1];
2057 		serial->port[1] = tmp;
2058 		serial->port[0]->interrupt_in_urb = tmp->interrupt_in_urb;
2059 		serial->port[0]->interrupt_in_buffer = tmp->interrupt_in_buffer;
2060 		serial->port[0]->interrupt_in_endpointAddress =
2061 			tmp->interrupt_in_endpointAddress;
2062 		serial->port[1]->interrupt_in_urb = NULL;
2063 		serial->port[1]->interrupt_in_buffer = NULL;
2064 	}
2065 
2066 
2067 	/* set up serial port private structures */
2068 	for (i = 0; i < serial->num_ports; ++i) {
2069 		mos7720_port = kzalloc(sizeof(struct moschip_port), GFP_KERNEL);
2070 		if (mos7720_port == NULL) {
2071 			dev_err(&dev->dev, "%s - Out of memory\n", __func__);
2072 			return -ENOMEM;
2073 		}
2074 
2075 		/* Initialize all port interrupt end point to port 0 int
2076 		 * endpoint.  Our device has only one interrupt endpoint
2077 		 * common to all ports */
2078 		serial->port[i]->interrupt_in_endpointAddress =
2079 				serial->port[0]->interrupt_in_endpointAddress;
2080 
2081 		mos7720_port->port = serial->port[i];
2082 		usb_set_serial_port_data(serial->port[i], mos7720_port);
2083 
2084 		dbg("port number is %d", serial->port[i]->number);
2085 		dbg("serial number is %d", serial->minor);
2086 	}
2087 
2088 
2089 	/* setting configuration feature to one */
2090 	usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
2091 			(__u8)0x03, 0x00, 0x01, 0x00, NULL, 0x00, 5*HZ);
2092 
2093 	/* start the interrupt urb */
2094 	ret_val = usb_submit_urb(serial->port[0]->interrupt_in_urb, GFP_KERNEL);
2095 	if (ret_val)
2096 		dev_err(&dev->dev,
2097 			"%s - Error %d submitting control urb\n",
2098 			__func__, ret_val);
2099 
2100 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
2101 	if (product == MOSCHIP_DEVICE_ID_7715) {
2102 		ret_val = mos7715_parport_init(serial);
2103 		if (ret_val < 0)
2104 			return ret_val;
2105 	}
2106 #endif
2107 	/* LSR For Port 1 */
2108 	read_mos_reg(serial, 0, LSR, &data);
2109 	dbg("LSR:%x", data);
2110 
2111 	return 0;
2112 }
2113 
2114 static void mos7720_release(struct usb_serial *serial)
2115 {
2116 	int i;
2117 
2118 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
2119 	/* close the parallel port */
2120 
2121 	if (le16_to_cpu(serial->dev->descriptor.idProduct)
2122 	    == MOSCHIP_DEVICE_ID_7715) {
2123 		struct urbtracker *urbtrack;
2124 		unsigned long flags;
2125 		struct mos7715_parport *mos_parport =
2126 			usb_get_serial_data(serial);
2127 
2128 		/* prevent NULL ptr dereference in port callbacks */
2129 		spin_lock(&release_lock);
2130 		mos_parport->pp->private_data = NULL;
2131 		spin_unlock(&release_lock);
2132 
2133 		/* wait for synchronous usb calls to return */
2134 		if (mos_parport->msg_pending)
2135 			wait_for_completion_timeout(&mos_parport->syncmsg_compl,
2136 						    MOS_WDR_TIMEOUT);
2137 
2138 		parport_remove_port(mos_parport->pp);
2139 		usb_set_serial_data(serial, NULL);
2140 		mos_parport->serial = NULL;
2141 
2142 		/* if tasklet currently scheduled, wait for it to complete */
2143 		tasklet_kill(&mos_parport->urb_tasklet);
2144 
2145 		/* unlink any urbs sent by the tasklet  */
2146 		spin_lock_irqsave(&mos_parport->listlock, flags);
2147 		list_for_each_entry(urbtrack,
2148 				    &mos_parport->active_urbs,
2149 				    urblist_entry)
2150 			usb_unlink_urb(urbtrack->urb);
2151 		spin_unlock_irqrestore(&mos_parport->listlock, flags);
2152 
2153 		kref_put(&mos_parport->ref_count, destroy_mos_parport);
2154 	}
2155 #endif
2156 	/* free private structure allocated for serial port */
2157 	for (i = 0; i < serial->num_ports; ++i)
2158 		kfree(usb_get_serial_port_data(serial->port[i]));
2159 }
2160 
2161 static struct usb_serial_driver moschip7720_2port_driver = {
2162 	.driver = {
2163 		.owner =	THIS_MODULE,
2164 		.name =		"moschip7720",
2165 	},
2166 	.description		= "Moschip 2 port adapter",
2167 	.id_table		= id_table,
2168 	.calc_num_ports		= mos77xx_calc_num_ports,
2169 	.open			= mos7720_open,
2170 	.close			= mos7720_close,
2171 	.throttle		= mos7720_throttle,
2172 	.unthrottle		= mos7720_unthrottle,
2173 	.probe			= mos77xx_probe,
2174 	.attach			= mos7720_startup,
2175 	.release		= mos7720_release,
2176 	.ioctl			= mos7720_ioctl,
2177 	.tiocmget		= mos7720_tiocmget,
2178 	.tiocmset		= mos7720_tiocmset,
2179 	.get_icount		= mos7720_get_icount,
2180 	.set_termios		= mos7720_set_termios,
2181 	.write			= mos7720_write,
2182 	.write_room		= mos7720_write_room,
2183 	.chars_in_buffer	= mos7720_chars_in_buffer,
2184 	.break_ctl		= mos7720_break,
2185 	.read_bulk_callback	= mos7720_bulk_in_callback,
2186 	.read_int_callback	= NULL  /* dynamically assigned in probe() */
2187 };
2188 
2189 static struct usb_serial_driver * const serial_drivers[] = {
2190 	&moschip7720_2port_driver, NULL
2191 };
2192 
2193 module_usb_serial_driver(serial_drivers, id_table);
2194 
2195 MODULE_AUTHOR(DRIVER_AUTHOR);
2196 MODULE_DESCRIPTION(DRIVER_DESC);
2197 MODULE_LICENSE("GPL");
2198 
2199 module_param(debug, bool, S_IRUGO | S_IWUSR);
2200 MODULE_PARM_DESC(debug, "Debug enabled or not");
2201