xref: /openbmc/linux/drivers/usb/serial/mos7720.c (revision 615c36f5)
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 int 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 moschip_port_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, moschip_port_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 	dbg("%s called", __func__);
261 	kfree(mos_parport);
262 }
263 
264 static void destroy_urbtracker(struct kref *kref)
265 {
266 	struct urbtracker *urbtrack =
267 		container_of(kref, struct urbtracker, ref_count);
268 	struct mos7715_parport *mos_parport = urbtrack->mos_parport;
269 	dbg("%s called", __func__);
270 	usb_free_urb(urbtrack->urb);
271 	kfree(urbtrack);
272 	kref_put(&mos_parport->ref_count, destroy_mos_parport);
273 }
274 
275 /*
276  * This runs as a tasklet when sending an urb in a non-blocking parallel
277  * port callback had to be deferred because the disconnect mutex could not be
278  * obtained at the time.
279  */
280 static void send_deferred_urbs(unsigned long _mos_parport)
281 {
282 	int ret_val;
283 	unsigned long flags;
284 	struct mos7715_parport *mos_parport = (void *)_mos_parport;
285 	struct urbtracker *urbtrack;
286 	struct list_head *cursor, *next;
287 
288 	dbg("%s called", __func__);
289 
290 	/* if release function ran, game over */
291 	if (unlikely(mos_parport->serial == NULL))
292 		return;
293 
294 	/* try again to get the mutex */
295 	if (!mutex_trylock(&mos_parport->serial->disc_mutex)) {
296 		dbg("%s: rescheduling tasklet", __func__);
297 		tasklet_schedule(&mos_parport->urb_tasklet);
298 		return;
299 	}
300 
301 	/* if device disconnected, game over */
302 	if (unlikely(mos_parport->serial->disconnected)) {
303 		mutex_unlock(&mos_parport->serial->disc_mutex);
304 		return;
305 	}
306 
307 	spin_lock_irqsave(&mos_parport->listlock, flags);
308 	if (list_empty(&mos_parport->deferred_urbs)) {
309 		spin_unlock_irqrestore(&mos_parport->listlock, flags);
310 		mutex_unlock(&mos_parport->serial->disc_mutex);
311 		dbg("%s: deferred_urbs list empty", __func__);
312 		return;
313 	}
314 
315 	/* move contents of deferred_urbs list to active_urbs list and submit */
316 	list_for_each_safe(cursor, next, &mos_parport->deferred_urbs)
317 		list_move_tail(cursor, &mos_parport->active_urbs);
318 	list_for_each_entry(urbtrack, &mos_parport->active_urbs,
319 			    urblist_entry) {
320 		ret_val = usb_submit_urb(urbtrack->urb, GFP_ATOMIC);
321 		dbg("%s: urb submitted", __func__);
322 		if (ret_val) {
323 			dev_err(&mos_parport->serial->dev->dev,
324 				"usb_submit_urb() failed: %d", ret_val);
325 			list_del(&urbtrack->urblist_entry);
326 			kref_put(&urbtrack->ref_count, destroy_urbtracker);
327 		}
328 	}
329 	spin_unlock_irqrestore(&mos_parport->listlock, flags);
330 	mutex_unlock(&mos_parport->serial->disc_mutex);
331 }
332 
333 /* callback for parallel port control urbs submitted asynchronously */
334 static void async_complete(struct urb *urb)
335 {
336 	struct urbtracker *urbtrack = urb->context;
337 	int status = urb->status;
338 	dbg("%s called", __func__);
339 	if (unlikely(status))
340 		dbg("%s - nonzero urb status received: %d", __func__, status);
341 
342 	/* remove the urbtracker from the active_urbs list */
343 	spin_lock(&urbtrack->mos_parport->listlock);
344 	list_del(&urbtrack->urblist_entry);
345 	spin_unlock(&urbtrack->mos_parport->listlock);
346 	kref_put(&urbtrack->ref_count, destroy_urbtracker);
347 }
348 
349 static int write_parport_reg_nonblock(struct mos7715_parport *mos_parport,
350 				      enum mos_regs reg, __u8 data)
351 {
352 	struct urbtracker *urbtrack;
353 	int ret_val;
354 	unsigned long flags;
355 	struct usb_ctrlrequest setup;
356 	struct usb_serial *serial = mos_parport->serial;
357 	struct usb_device *usbdev = serial->dev;
358 	dbg("%s called", __func__);
359 
360 	/* create and initialize the control urb and containing urbtracker */
361 	urbtrack = kmalloc(sizeof(struct urbtracker), GFP_ATOMIC);
362 	if (urbtrack == NULL) {
363 		dev_err(&usbdev->dev, "out of memory");
364 		return -ENOMEM;
365 	}
366 	kref_get(&mos_parport->ref_count);
367 	urbtrack->mos_parport = mos_parport;
368 	urbtrack->urb = usb_alloc_urb(0, GFP_ATOMIC);
369 	if (urbtrack->urb == NULL) {
370 		dev_err(&usbdev->dev, "out of urbs");
371 		kfree(urbtrack);
372 		return -ENOMEM;
373 	}
374 	setup.bRequestType = (__u8)0x40;
375 	setup.bRequest = (__u8)0x0e;
376 	setup.wValue = get_reg_value(reg, dummy);
377 	setup.wIndex = get_reg_index(reg);
378 	setup.wLength = 0;
379 	usb_fill_control_urb(urbtrack->urb, usbdev,
380 			     usb_sndctrlpipe(usbdev, 0),
381 			     (unsigned char *)&setup,
382 			     NULL, 0, async_complete, urbtrack);
383 	kref_init(&urbtrack->ref_count);
384 	INIT_LIST_HEAD(&urbtrack->urblist_entry);
385 
386 	/*
387 	 * get the disconnect mutex, or add tracker to the deferred_urbs list
388 	 * and schedule a tasklet to try again later
389 	 */
390 	if (!mutex_trylock(&serial->disc_mutex)) {
391 		spin_lock_irqsave(&mos_parport->listlock, flags);
392 		list_add_tail(&urbtrack->urblist_entry,
393 			      &mos_parport->deferred_urbs);
394 		spin_unlock_irqrestore(&mos_parport->listlock, flags);
395 		tasklet_schedule(&mos_parport->urb_tasklet);
396 		dbg("tasklet scheduled");
397 		return 0;
398 	}
399 
400 	/* bail if device disconnected */
401 	if (serial->disconnected) {
402 		kref_put(&urbtrack->ref_count, destroy_urbtracker);
403 		mutex_unlock(&serial->disc_mutex);
404 		return -ENODEV;
405 	}
406 
407 	/* add the tracker to the active_urbs list and submit */
408 	spin_lock_irqsave(&mos_parport->listlock, flags);
409 	list_add_tail(&urbtrack->urblist_entry, &mos_parport->active_urbs);
410 	spin_unlock_irqrestore(&mos_parport->listlock, flags);
411 	ret_val = usb_submit_urb(urbtrack->urb, GFP_ATOMIC);
412 	mutex_unlock(&serial->disc_mutex);
413 	if (ret_val) {
414 		dev_err(&usbdev->dev,
415 			"%s: submit_urb() failed: %d", __func__, ret_val);
416 		spin_lock_irqsave(&mos_parport->listlock, flags);
417 		list_del(&urbtrack->urblist_entry);
418 		spin_unlock_irqrestore(&mos_parport->listlock, flags);
419 		kref_put(&urbtrack->ref_count, destroy_urbtracker);
420 		return ret_val;
421 	}
422 	return 0;
423 }
424 
425 /*
426  * This is the the common top part of all parallel port callback operations that
427  * send synchronous messages to the device.  This implements convoluted locking
428  * that avoids two scenarios: (1) a port operation is called after usbserial
429  * has called our release function, at which point struct mos7715_parport has
430  * been destroyed, and (2) the device has been disconnected, but usbserial has
431  * not called the release function yet because someone has a serial port open.
432  * The shared release_lock prevents the first, and the mutex and disconnected
433  * flag maintained by usbserial covers the second.  We also use the msg_pending
434  * flag to ensure that all synchronous usb messgage calls have completed before
435  * our release function can return.
436  */
437 static int parport_prologue(struct parport *pp)
438 {
439 	struct mos7715_parport *mos_parport;
440 
441 	spin_lock(&release_lock);
442 	mos_parport = pp->private_data;
443 	if (unlikely(mos_parport == NULL)) {
444 		/* release fn called, port struct destroyed */
445 		spin_unlock(&release_lock);
446 		return -1;
447 	}
448 	mos_parport->msg_pending = true;   /* synch usb call pending */
449 	INIT_COMPLETION(mos_parport->syncmsg_compl);
450 	spin_unlock(&release_lock);
451 
452 	mutex_lock(&mos_parport->serial->disc_mutex);
453 	if (mos_parport->serial->disconnected) {
454 		/* device disconnected */
455 		mutex_unlock(&mos_parport->serial->disc_mutex);
456 		mos_parport->msg_pending = false;
457 		complete(&mos_parport->syncmsg_compl);
458 		return -1;
459 	}
460 
461 	return 0;
462 }
463 
464 /*
465  * This is the the common bottom part of all parallel port functions that send
466  * synchronous messages to the device.
467  */
468 static inline void parport_epilogue(struct parport *pp)
469 {
470 	struct mos7715_parport *mos_parport = pp->private_data;
471 	mutex_unlock(&mos_parport->serial->disc_mutex);
472 	mos_parport->msg_pending = false;
473 	complete(&mos_parport->syncmsg_compl);
474 }
475 
476 static void parport_mos7715_write_data(struct parport *pp, unsigned char d)
477 {
478 	struct mos7715_parport *mos_parport = pp->private_data;
479 	dbg("%s called: %2.2x", __func__, d);
480 	if (parport_prologue(pp) < 0)
481 		return;
482 	mos7715_change_mode(mos_parport, SPP);
483 	write_mos_reg(mos_parport->serial, dummy, DPR, (__u8)d);
484 	parport_epilogue(pp);
485 }
486 
487 static unsigned char parport_mos7715_read_data(struct parport *pp)
488 {
489 	struct mos7715_parport *mos_parport = pp->private_data;
490 	unsigned char d;
491 	dbg("%s called", __func__);
492 	if (parport_prologue(pp) < 0)
493 		return 0;
494 	read_mos_reg(mos_parport->serial, dummy, DPR, &d);
495 	parport_epilogue(pp);
496 	return d;
497 }
498 
499 static void parport_mos7715_write_control(struct parport *pp, unsigned char d)
500 {
501 	struct mos7715_parport *mos_parport = pp->private_data;
502 	__u8 data;
503 	dbg("%s called: %2.2x", __func__, d);
504 	if (parport_prologue(pp) < 0)
505 		return;
506 	data = ((__u8)d & 0x0f) | (mos_parport->shadowDCR & 0xf0);
507 	write_mos_reg(mos_parport->serial, dummy, DCR, data);
508 	mos_parport->shadowDCR = data;
509 	parport_epilogue(pp);
510 }
511 
512 static unsigned char parport_mos7715_read_control(struct parport *pp)
513 {
514 	struct mos7715_parport *mos_parport = pp->private_data;
515 	__u8 dcr;
516 	dbg("%s called", __func__);
517 	spin_lock(&release_lock);
518 	mos_parport = pp->private_data;
519 	if (unlikely(mos_parport == NULL)) {
520 		spin_unlock(&release_lock);
521 		return 0;
522 	}
523 	dcr = mos_parport->shadowDCR & 0x0f;
524 	spin_unlock(&release_lock);
525 	return dcr;
526 }
527 
528 static unsigned char parport_mos7715_frob_control(struct parport *pp,
529 						  unsigned char mask,
530 						  unsigned char val)
531 {
532 	struct mos7715_parport *mos_parport = pp->private_data;
533 	__u8 dcr;
534 	dbg("%s called", __func__);
535 	mask &= 0x0f;
536 	val &= 0x0f;
537 	if (parport_prologue(pp) < 0)
538 		return 0;
539 	mos_parport->shadowDCR = (mos_parport->shadowDCR & (~mask)) ^ val;
540 	write_mos_reg(mos_parport->serial, dummy, DCR, mos_parport->shadowDCR);
541 	dcr = mos_parport->shadowDCR & 0x0f;
542 	parport_epilogue(pp);
543 	return dcr;
544 }
545 
546 static unsigned char parport_mos7715_read_status(struct parport *pp)
547 {
548 	unsigned char status;
549 	struct mos7715_parport *mos_parport = pp->private_data;
550 	dbg("%s called", __func__);
551 	spin_lock(&release_lock);
552 	mos_parport = pp->private_data;
553 	if (unlikely(mos_parport == NULL)) {	/* release called */
554 		spin_unlock(&release_lock);
555 		return 0;
556 	}
557 	status = atomic_read(&mos_parport->shadowDSR) & 0xf8;
558 	spin_unlock(&release_lock);
559 	return status;
560 }
561 
562 static void parport_mos7715_enable_irq(struct parport *pp)
563 {
564 	dbg("%s called", __func__);
565 }
566 static void parport_mos7715_disable_irq(struct parport *pp)
567 {
568 	dbg("%s called", __func__);
569 }
570 
571 static void parport_mos7715_data_forward(struct parport *pp)
572 {
573 	struct mos7715_parport *mos_parport = pp->private_data;
574 	dbg("%s called", __func__);
575 	if (parport_prologue(pp) < 0)
576 		return;
577 	mos7715_change_mode(mos_parport, PS2);
578 	mos_parport->shadowDCR &=  ~0x20;
579 	write_mos_reg(mos_parport->serial, dummy, DCR, mos_parport->shadowDCR);
580 	parport_epilogue(pp);
581 }
582 
583 static void parport_mos7715_data_reverse(struct parport *pp)
584 {
585 	struct mos7715_parport *mos_parport = pp->private_data;
586 	dbg("%s called", __func__);
587 	if (parport_prologue(pp) < 0)
588 		return;
589 	mos7715_change_mode(mos_parport, PS2);
590 	mos_parport->shadowDCR |= 0x20;
591 	write_mos_reg(mos_parport->serial, dummy, DCR, mos_parport->shadowDCR);
592 	parport_epilogue(pp);
593 }
594 
595 static void parport_mos7715_init_state(struct pardevice *dev,
596 				       struct parport_state *s)
597 {
598 	dbg("%s called", __func__);
599 	s->u.pc.ctr = DCR_INIT_VAL;
600 	s->u.pc.ecr = ECR_INIT_VAL;
601 }
602 
603 /* N.B. Parport core code requires that this function not block */
604 static void parport_mos7715_save_state(struct parport *pp,
605 				       struct parport_state *s)
606 {
607 	struct mos7715_parport *mos_parport;
608 	dbg("%s called", __func__);
609 	spin_lock(&release_lock);
610 	mos_parport = pp->private_data;
611 	if (unlikely(mos_parport == NULL)) {	/* release called */
612 		spin_unlock(&release_lock);
613 		return;
614 	}
615 	s->u.pc.ctr = mos_parport->shadowDCR;
616 	s->u.pc.ecr = mos_parport->shadowECR;
617 	spin_unlock(&release_lock);
618 }
619 
620 /* N.B. Parport core code requires that this function not block */
621 static void parport_mos7715_restore_state(struct parport *pp,
622 					  struct parport_state *s)
623 {
624 	struct mos7715_parport *mos_parport;
625 	dbg("%s called", __func__);
626 	spin_lock(&release_lock);
627 	mos_parport = pp->private_data;
628 	if (unlikely(mos_parport == NULL)) {	/* release called */
629 		spin_unlock(&release_lock);
630 		return;
631 	}
632 	write_parport_reg_nonblock(mos_parport, DCR, mos_parport->shadowDCR);
633 	write_parport_reg_nonblock(mos_parport, ECR, mos_parport->shadowECR);
634 	spin_unlock(&release_lock);
635 }
636 
637 static size_t parport_mos7715_write_compat(struct parport *pp,
638 					   const void *buffer,
639 					   size_t len, int flags)
640 {
641 	int retval;
642 	struct mos7715_parport *mos_parport = pp->private_data;
643 	int actual_len;
644 	dbg("%s called: %u chars", __func__, (unsigned int)len);
645 	if (parport_prologue(pp) < 0)
646 		return 0;
647 	mos7715_change_mode(mos_parport, PPF);
648 	retval = usb_bulk_msg(mos_parport->serial->dev,
649 			      usb_sndbulkpipe(mos_parport->serial->dev, 2),
650 			      (void *)buffer, len, &actual_len,
651 			      MOS_WDR_TIMEOUT);
652 	parport_epilogue(pp);
653 	if (retval) {
654 		dev_err(&mos_parport->serial->dev->dev,
655 			"mos7720: usb_bulk_msg() failed: %d", retval);
656 		return 0;
657 	}
658 	return actual_len;
659 }
660 
661 static struct parport_operations parport_mos7715_ops = {
662 	.owner =		THIS_MODULE,
663 	.write_data =		parport_mos7715_write_data,
664 	.read_data =		parport_mos7715_read_data,
665 
666 	.write_control =	parport_mos7715_write_control,
667 	.read_control =		parport_mos7715_read_control,
668 	.frob_control =		parport_mos7715_frob_control,
669 
670 	.read_status =		parport_mos7715_read_status,
671 
672 	.enable_irq =		parport_mos7715_enable_irq,
673 	.disable_irq =		parport_mos7715_disable_irq,
674 
675 	.data_forward =		parport_mos7715_data_forward,
676 	.data_reverse =		parport_mos7715_data_reverse,
677 
678 	.init_state =		parport_mos7715_init_state,
679 	.save_state =		parport_mos7715_save_state,
680 	.restore_state =	parport_mos7715_restore_state,
681 
682 	.compat_write_data =	parport_mos7715_write_compat,
683 
684 	.nibble_read_data =	parport_ieee1284_read_nibble,
685 	.byte_read_data =	parport_ieee1284_read_byte,
686 };
687 
688 /*
689  * Allocate and initialize parallel port control struct, initialize
690  * the parallel port hardware device, and register with the parport subsystem.
691  */
692 static int mos7715_parport_init(struct usb_serial *serial)
693 {
694 	struct mos7715_parport *mos_parport;
695 
696 	/* allocate and initialize parallel port control struct */
697 	mos_parport = kzalloc(sizeof(struct mos7715_parport), GFP_KERNEL);
698 	if (mos_parport == NULL) {
699 		dbg("mos7715_parport_init: kzalloc failed");
700 		return -ENOMEM;
701 	}
702 	mos_parport->msg_pending = false;
703 	kref_init(&mos_parport->ref_count);
704 	spin_lock_init(&mos_parport->listlock);
705 	INIT_LIST_HEAD(&mos_parport->active_urbs);
706 	INIT_LIST_HEAD(&mos_parport->deferred_urbs);
707 	usb_set_serial_data(serial, mos_parport); /* hijack private pointer */
708 	mos_parport->serial = serial;
709 	tasklet_init(&mos_parport->urb_tasklet, send_deferred_urbs,
710 		     (unsigned long) mos_parport);
711 	init_completion(&mos_parport->syncmsg_compl);
712 
713 	/* cycle parallel port reset bit */
714 	write_mos_reg(mos_parport->serial, dummy, PP_REG, (__u8)0x80);
715 	write_mos_reg(mos_parport->serial, dummy, PP_REG, (__u8)0x00);
716 
717 	/* initialize device registers */
718 	mos_parport->shadowDCR = DCR_INIT_VAL;
719 	write_mos_reg(mos_parport->serial, dummy, DCR, mos_parport->shadowDCR);
720 	mos_parport->shadowECR = ECR_INIT_VAL;
721 	write_mos_reg(mos_parport->serial, dummy, ECR, mos_parport->shadowECR);
722 
723 	/* register with parport core */
724 	mos_parport->pp = parport_register_port(0, PARPORT_IRQ_NONE,
725 						PARPORT_DMA_NONE,
726 						&parport_mos7715_ops);
727 	if (mos_parport->pp == NULL) {
728 		dev_err(&serial->interface->dev,
729 			"Could not register parport\n");
730 		kref_put(&mos_parport->ref_count, destroy_mos_parport);
731 		return -EIO;
732 	}
733 	mos_parport->pp->private_data = mos_parport;
734 	mos_parport->pp->modes = PARPORT_MODE_COMPAT | PARPORT_MODE_PCSPP;
735 	mos_parport->pp->dev = &serial->interface->dev;
736 	parport_announce_port(mos_parport->pp);
737 
738 	return 0;
739 }
740 #endif	/* CONFIG_USB_SERIAL_MOS7715_PARPORT */
741 
742 /*
743  * mos7720_interrupt_callback
744  *	this is the callback function for when we have received data on the
745  *	interrupt endpoint.
746  */
747 static void mos7720_interrupt_callback(struct urb *urb)
748 {
749 	int result;
750 	int length;
751 	int status = urb->status;
752 	__u8 *data;
753 	__u8 sp1;
754 	__u8 sp2;
755 
756 	switch (status) {
757 	case 0:
758 		/* success */
759 		break;
760 	case -ECONNRESET:
761 	case -ENOENT:
762 	case -ESHUTDOWN:
763 		/* this urb is terminated, clean up */
764 		dbg("%s - urb shutting down with status: %d", __func__,
765 		    status);
766 		return;
767 	default:
768 		dbg("%s - nonzero urb status received: %d", __func__,
769 		    status);
770 		goto exit;
771 	}
772 
773 	length = urb->actual_length;
774 	data = urb->transfer_buffer;
775 
776 	/* Moschip get 4 bytes
777 	 * Byte 1 IIR Port 1 (port.number is 0)
778 	 * Byte 2 IIR Port 2 (port.number is 1)
779 	 * Byte 3 --------------
780 	 * Byte 4 FIFO status for both */
781 
782 	/* the above description is inverted
783 	 * 	oneukum 2007-03-14 */
784 
785 	if (unlikely(length != 4)) {
786 		dbg("Wrong data !!!");
787 		return;
788 	}
789 
790 	sp1 = data[3];
791 	sp2 = data[2];
792 
793 	if ((sp1 | sp2) & 0x01) {
794 		/* No Interrupt Pending in both the ports */
795 		dbg("No Interrupt !!!");
796 	} else {
797 		switch (sp1 & 0x0f) {
798 		case SERIAL_IIR_RLS:
799 			dbg("Serial Port 1: Receiver status error or address "
800 			    "bit detected in 9-bit mode\n");
801 			break;
802 		case SERIAL_IIR_CTI:
803 			dbg("Serial Port 1: Receiver time out");
804 			break;
805 		case SERIAL_IIR_MS:
806 			/* dbg("Serial Port 1: Modem status change"); */
807 			break;
808 		}
809 
810 		switch (sp2 & 0x0f) {
811 		case SERIAL_IIR_RLS:
812 			dbg("Serial Port 2: Receiver status error or address "
813 			    "bit detected in 9-bit mode");
814 			break;
815 		case SERIAL_IIR_CTI:
816 			dbg("Serial Port 2: Receiver time out");
817 			break;
818 		case SERIAL_IIR_MS:
819 			/* dbg("Serial Port 2: Modem status change"); */
820 			break;
821 		}
822 	}
823 
824 exit:
825 	result = usb_submit_urb(urb, GFP_ATOMIC);
826 	if (result)
827 		dev_err(&urb->dev->dev,
828 			"%s - Error %d submitting control urb\n",
829 			__func__, result);
830 }
831 
832 /*
833  * mos7715_interrupt_callback
834  *	this is the 7715's callback function for when we have received data on
835  *	the interrupt endpoint.
836  */
837 static void mos7715_interrupt_callback(struct urb *urb)
838 {
839 	int result;
840 	int length;
841 	int status = urb->status;
842 	__u8 *data;
843 	__u8 iir;
844 
845 	switch (status) {
846 	case 0:
847 		/* success */
848 		break;
849 	case -ECONNRESET:
850 	case -ENOENT:
851 	case -ESHUTDOWN:
852 	case -ENODEV:
853 		/* this urb is terminated, clean up */
854 		dbg("%s - urb shutting down with status: %d", __func__,
855 		    status);
856 		return;
857 	default:
858 		dbg("%s - nonzero urb status received: %d", __func__,
859 		    status);
860 		goto exit;
861 	}
862 
863 	length = urb->actual_length;
864 	data = urb->transfer_buffer;
865 
866 	/* Structure of data from 7715 device:
867 	 * Byte 1: IIR serial Port
868 	 * Byte 2: unused
869 	 * Byte 2: DSR parallel port
870 	 * Byte 4: FIFO status for both */
871 
872 	if (unlikely(length != 4)) {
873 		dbg("Wrong data !!!");
874 		return;
875 	}
876 
877 	iir = data[0];
878 	if (!(iir & 0x01)) {	/* serial port interrupt pending */
879 		switch (iir & 0x0f) {
880 		case SERIAL_IIR_RLS:
881 			dbg("Serial Port: Receiver status error or address "
882 			    "bit detected in 9-bit mode\n");
883 			break;
884 		case SERIAL_IIR_CTI:
885 			dbg("Serial Port: Receiver time out");
886 			break;
887 		case SERIAL_IIR_MS:
888 			/* dbg("Serial Port: Modem status change"); */
889 			break;
890 		}
891 	}
892 
893 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
894 	{       /* update local copy of DSR reg */
895 		struct usb_serial_port *port = urb->context;
896 		struct mos7715_parport *mos_parport = port->serial->private;
897 		if (unlikely(mos_parport == NULL))
898 			return;
899 		atomic_set(&mos_parport->shadowDSR, data[2]);
900 	}
901 #endif
902 
903 exit:
904 	result = usb_submit_urb(urb, GFP_ATOMIC);
905 	if (result)
906 		dev_err(&urb->dev->dev,
907 			"%s - Error %d submitting control urb\n",
908 			__func__, result);
909 }
910 
911 /*
912  * mos7720_bulk_in_callback
913  *	this is the callback function for when we have received data on the
914  *	bulk in endpoint.
915  */
916 static void mos7720_bulk_in_callback(struct urb *urb)
917 {
918 	int retval;
919 	unsigned char *data ;
920 	struct usb_serial_port *port;
921 	struct tty_struct *tty;
922 	int status = urb->status;
923 
924 	if (status) {
925 		dbg("nonzero read bulk status received: %d", status);
926 		return;
927 	}
928 
929 	port = urb->context;
930 
931 	dbg("Entering...%s", __func__);
932 
933 	data = urb->transfer_buffer;
934 
935 	tty = tty_port_tty_get(&port->port);
936 	if (tty && urb->actual_length) {
937 		tty_insert_flip_string(tty, data, urb->actual_length);
938 		tty_flip_buffer_push(tty);
939 	}
940 	tty_kref_put(tty);
941 
942 	if (!port->read_urb) {
943 		dbg("URB KILLED !!!");
944 		return;
945 	}
946 
947 	if (port->read_urb->status != -EINPROGRESS) {
948 		port->read_urb->dev = port->serial->dev;
949 
950 		retval = usb_submit_urb(port->read_urb, GFP_ATOMIC);
951 		if (retval)
952 			dbg("usb_submit_urb(read bulk) failed, retval = %d",
953 			    retval);
954 	}
955 }
956 
957 /*
958  * mos7720_bulk_out_data_callback
959  *	this is the callback function for when we have finished sending serial
960  *	data on the bulk out endpoint.
961  */
962 static void mos7720_bulk_out_data_callback(struct urb *urb)
963 {
964 	struct moschip_port *mos7720_port;
965 	struct tty_struct *tty;
966 	int status = urb->status;
967 
968 	if (status) {
969 		dbg("nonzero write bulk status received:%d", status);
970 		return;
971 	}
972 
973 	mos7720_port = urb->context;
974 	if (!mos7720_port) {
975 		dbg("NULL mos7720_port pointer");
976 		return ;
977 	}
978 
979 	tty = tty_port_tty_get(&mos7720_port->port->port);
980 
981 	if (tty && mos7720_port->open)
982 		tty_wakeup(tty);
983 	tty_kref_put(tty);
984 }
985 
986 /*
987  * mos77xx_probe
988  *	this function installs the appropriate read interrupt endpoint callback
989  *	depending on whether the device is a 7720 or 7715, thus avoiding costly
990  *	run-time checks in the high-frequency callback routine itself.
991  */
992 static int mos77xx_probe(struct usb_serial *serial,
993 			 const struct usb_device_id *id)
994 {
995 	if (id->idProduct == MOSCHIP_DEVICE_ID_7715)
996 		moschip7720_2port_driver.read_int_callback =
997 			mos7715_interrupt_callback;
998 	else
999 		moschip7720_2port_driver.read_int_callback =
1000 			mos7720_interrupt_callback;
1001 
1002 	return 0;
1003 }
1004 
1005 static int mos77xx_calc_num_ports(struct usb_serial *serial)
1006 {
1007 	u16 product = le16_to_cpu(serial->dev->descriptor.idProduct);
1008 	if (product == MOSCHIP_DEVICE_ID_7715)
1009 		return 1;
1010 
1011 	return 2;
1012 }
1013 
1014 static int mos7720_open(struct tty_struct *tty, struct usb_serial_port *port)
1015 {
1016 	struct usb_serial *serial;
1017 	struct usb_serial_port *port0;
1018 	struct urb *urb;
1019 	struct moschip_port *mos7720_port;
1020 	int response;
1021 	int port_number;
1022 	__u8 data;
1023 	int allocated_urbs = 0;
1024 	int j;
1025 
1026 	serial = port->serial;
1027 
1028 	mos7720_port = usb_get_serial_port_data(port);
1029 	if (mos7720_port == NULL)
1030 		return -ENODEV;
1031 
1032 	port0 = serial->port[0];
1033 
1034 	usb_clear_halt(serial->dev, port->write_urb->pipe);
1035 	usb_clear_halt(serial->dev, port->read_urb->pipe);
1036 
1037 	/* Initialising the write urb pool */
1038 	for (j = 0; j < NUM_URBS; ++j) {
1039 		urb = usb_alloc_urb(0, GFP_KERNEL);
1040 		mos7720_port->write_urb_pool[j] = urb;
1041 
1042 		if (urb == NULL) {
1043 			dev_err(&port->dev, "No more urbs???\n");
1044 			continue;
1045 		}
1046 
1047 		urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE,
1048 					       GFP_KERNEL);
1049 		if (!urb->transfer_buffer) {
1050 			dev_err(&port->dev,
1051 				"%s-out of memory for urb buffers.\n",
1052 				__func__);
1053 			usb_free_urb(mos7720_port->write_urb_pool[j]);
1054 			mos7720_port->write_urb_pool[j] = NULL;
1055 			continue;
1056 		}
1057 		allocated_urbs++;
1058 	}
1059 
1060 	if (!allocated_urbs)
1061 		return -ENOMEM;
1062 
1063 	 /* Initialize MCS7720 -- Write Init values to corresponding Registers
1064 	  *
1065 	  * Register Index
1066 	  * 0 : THR/RHR
1067 	  * 1 : IER
1068 	  * 2 : FCR
1069 	  * 3 : LCR
1070 	  * 4 : MCR
1071 	  * 5 : LSR
1072 	  * 6 : MSR
1073 	  * 7 : SPR
1074 	  *
1075 	  * 0x08 : SP1/2 Control Reg
1076 	  */
1077 	port_number = port->number - port->serial->minor;
1078 	read_mos_reg(serial, port_number, LSR, &data);
1079 
1080 	dbg("SS::%p LSR:%x", mos7720_port, data);
1081 
1082 	dbg("Check:Sending Command ..........");
1083 
1084 	write_mos_reg(serial, dummy, SP1_REG, 0x02);
1085 	write_mos_reg(serial, dummy, SP2_REG, 0x02);
1086 
1087 	write_mos_reg(serial, port_number, IER, 0x00);
1088 	write_mos_reg(serial, port_number, FCR, 0x00);
1089 
1090 	write_mos_reg(serial, port_number, FCR, 0xcf);
1091 	mos7720_port->shadowLCR = 0x03;
1092 	write_mos_reg(serial, port_number, LCR, mos7720_port->shadowLCR);
1093 	mos7720_port->shadowMCR = 0x0b;
1094 	write_mos_reg(serial, port_number, MCR, mos7720_port->shadowMCR);
1095 
1096 	write_mos_reg(serial, port_number, SP_CONTROL_REG, 0x00);
1097 	read_mos_reg(serial, dummy, SP_CONTROL_REG, &data);
1098 	data = data | (port->number - port->serial->minor + 1);
1099 	write_mos_reg(serial, dummy, SP_CONTROL_REG, data);
1100 	mos7720_port->shadowLCR = 0x83;
1101 	write_mos_reg(serial, port_number, LCR, mos7720_port->shadowLCR);
1102 	write_mos_reg(serial, port_number, THR, 0x0c);
1103 	write_mos_reg(serial, port_number, IER, 0x00);
1104 	mos7720_port->shadowLCR = 0x03;
1105 	write_mos_reg(serial, port_number, LCR, mos7720_port->shadowLCR);
1106 	write_mos_reg(serial, port_number, IER, 0x0c);
1107 
1108 	response = usb_submit_urb(port->read_urb, GFP_KERNEL);
1109 	if (response)
1110 		dev_err(&port->dev, "%s - Error %d submitting read urb\n",
1111 							__func__, response);
1112 
1113 	/* initialize our icount structure */
1114 	memset(&(mos7720_port->icount), 0x00, sizeof(mos7720_port->icount));
1115 
1116 	/* initialize our port settings */
1117 	mos7720_port->shadowMCR = UART_MCR_OUT2; /* Must set to enable ints! */
1118 
1119 	/* send a open port command */
1120 	mos7720_port->open = 1;
1121 
1122 	return 0;
1123 }
1124 
1125 /*
1126  * mos7720_chars_in_buffer
1127  *	this function is called by the tty driver when it wants to know how many
1128  *	bytes of data we currently have outstanding in the port (data that has
1129  *	been written, but hasn't made it out the port yet)
1130  *	If successful, we return the number of bytes left to be written in the
1131  *	system,
1132  *	Otherwise we return a negative error number.
1133  */
1134 static int mos7720_chars_in_buffer(struct tty_struct *tty)
1135 {
1136 	struct usb_serial_port *port = tty->driver_data;
1137 	int i;
1138 	int chars = 0;
1139 	struct moschip_port *mos7720_port;
1140 
1141 	dbg("%s:entering ...........", __func__);
1142 
1143 	mos7720_port = usb_get_serial_port_data(port);
1144 	if (mos7720_port == NULL) {
1145 		dbg("%s:leaving ...........", __func__);
1146 		return 0;
1147 	}
1148 
1149 	for (i = 0; i < NUM_URBS; ++i) {
1150 		if (mos7720_port->write_urb_pool[i] &&
1151 		    mos7720_port->write_urb_pool[i]->status == -EINPROGRESS)
1152 			chars += URB_TRANSFER_BUFFER_SIZE;
1153 	}
1154 	dbg("%s - returns %d", __func__, chars);
1155 	return chars;
1156 }
1157 
1158 static void mos7720_close(struct usb_serial_port *port)
1159 {
1160 	struct usb_serial *serial;
1161 	struct moschip_port *mos7720_port;
1162 	int j;
1163 
1164 	dbg("mos7720_close:entering...");
1165 
1166 	serial = port->serial;
1167 
1168 	mos7720_port = usb_get_serial_port_data(port);
1169 	if (mos7720_port == NULL)
1170 		return;
1171 
1172 	for (j = 0; j < NUM_URBS; ++j)
1173 		usb_kill_urb(mos7720_port->write_urb_pool[j]);
1174 
1175 	/* Freeing Write URBs */
1176 	for (j = 0; j < NUM_URBS; ++j) {
1177 		if (mos7720_port->write_urb_pool[j]) {
1178 			kfree(mos7720_port->write_urb_pool[j]->transfer_buffer);
1179 			usb_free_urb(mos7720_port->write_urb_pool[j]);
1180 		}
1181 	}
1182 
1183 	/* While closing port, shutdown all bulk read, write  *
1184 	 * and interrupt read if they exists, otherwise nop   */
1185 	dbg("Shutdown bulk write");
1186 	usb_kill_urb(port->write_urb);
1187 	dbg("Shutdown bulk read");
1188 	usb_kill_urb(port->read_urb);
1189 
1190 	mutex_lock(&serial->disc_mutex);
1191 	/* these commands must not be issued if the device has
1192 	 * been disconnected */
1193 	if (!serial->disconnected) {
1194 		write_mos_reg(serial, port->number - port->serial->minor,
1195 			      MCR, 0x00);
1196 		write_mos_reg(serial, port->number - port->serial->minor,
1197 			      IER, 0x00);
1198 	}
1199 	mutex_unlock(&serial->disc_mutex);
1200 	mos7720_port->open = 0;
1201 
1202 	dbg("Leaving %s", __func__);
1203 }
1204 
1205 static void mos7720_break(struct tty_struct *tty, int break_state)
1206 {
1207 	struct usb_serial_port *port = tty->driver_data;
1208 	unsigned char data;
1209 	struct usb_serial *serial;
1210 	struct moschip_port *mos7720_port;
1211 
1212 	dbg("Entering %s", __func__);
1213 
1214 	serial = port->serial;
1215 
1216 	mos7720_port = usb_get_serial_port_data(port);
1217 	if (mos7720_port == NULL)
1218 		return;
1219 
1220 	if (break_state == -1)
1221 		data = mos7720_port->shadowLCR | UART_LCR_SBC;
1222 	else
1223 		data = mos7720_port->shadowLCR & ~UART_LCR_SBC;
1224 
1225 	mos7720_port->shadowLCR  = data;
1226 	write_mos_reg(serial, port->number - port->serial->minor,
1227 		      LCR, mos7720_port->shadowLCR);
1228 }
1229 
1230 /*
1231  * mos7720_write_room
1232  *	this function is called by the tty driver when it wants to know how many
1233  *	bytes of data we can accept for a specific port.
1234  *	If successful, we return the amount of room that we have for this port
1235  *	Otherwise we return a negative error number.
1236  */
1237 static int mos7720_write_room(struct tty_struct *tty)
1238 {
1239 	struct usb_serial_port *port = tty->driver_data;
1240 	struct moschip_port *mos7720_port;
1241 	int room = 0;
1242 	int i;
1243 
1244 	dbg("%s:entering ...........", __func__);
1245 
1246 	mos7720_port = usb_get_serial_port_data(port);
1247 	if (mos7720_port == NULL) {
1248 		dbg("%s:leaving ...........", __func__);
1249 		return -ENODEV;
1250 	}
1251 
1252 	/* FIXME: Locking */
1253 	for (i = 0; i < NUM_URBS; ++i) {
1254 		if (mos7720_port->write_urb_pool[i] &&
1255 		    mos7720_port->write_urb_pool[i]->status != -EINPROGRESS)
1256 			room += URB_TRANSFER_BUFFER_SIZE;
1257 	}
1258 
1259 	dbg("%s - returns %d", __func__, room);
1260 	return room;
1261 }
1262 
1263 static int mos7720_write(struct tty_struct *tty, struct usb_serial_port *port,
1264 				 const unsigned char *data, int count)
1265 {
1266 	int status;
1267 	int i;
1268 	int bytes_sent = 0;
1269 	int transfer_size;
1270 
1271 	struct moschip_port *mos7720_port;
1272 	struct usb_serial *serial;
1273 	struct urb    *urb;
1274 	const unsigned char *current_position = data;
1275 
1276 	dbg("%s:entering ...........", __func__);
1277 
1278 	serial = port->serial;
1279 
1280 	mos7720_port = usb_get_serial_port_data(port);
1281 	if (mos7720_port == NULL) {
1282 		dbg("mos7720_port is NULL");
1283 		return -ENODEV;
1284 	}
1285 
1286 	/* try to find a free urb in the list */
1287 	urb = NULL;
1288 
1289 	for (i = 0; i < NUM_URBS; ++i) {
1290 		if (mos7720_port->write_urb_pool[i] &&
1291 		    mos7720_port->write_urb_pool[i]->status != -EINPROGRESS) {
1292 			urb = mos7720_port->write_urb_pool[i];
1293 			dbg("URB:%d", i);
1294 			break;
1295 		}
1296 	}
1297 
1298 	if (urb == NULL) {
1299 		dbg("%s - no more free urbs", __func__);
1300 		goto exit;
1301 	}
1302 
1303 	if (urb->transfer_buffer == NULL) {
1304 		urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE,
1305 					       GFP_KERNEL);
1306 		if (urb->transfer_buffer == NULL) {
1307 			dev_err(&port->dev, "%s no more kernel memory...\n",
1308 				__func__);
1309 			goto exit;
1310 		}
1311 	}
1312 	transfer_size = min(count, URB_TRANSFER_BUFFER_SIZE);
1313 
1314 	memcpy(urb->transfer_buffer, current_position, transfer_size);
1315 	usb_serial_debug_data(debug, &port->dev, __func__, transfer_size,
1316 			      urb->transfer_buffer);
1317 
1318 	/* fill urb with data and submit  */
1319 	usb_fill_bulk_urb(urb, serial->dev,
1320 			  usb_sndbulkpipe(serial->dev,
1321 					port->bulk_out_endpointAddress),
1322 			  urb->transfer_buffer, transfer_size,
1323 			  mos7720_bulk_out_data_callback, mos7720_port);
1324 
1325 	/* send it down the pipe */
1326 	status = usb_submit_urb(urb, GFP_ATOMIC);
1327 	if (status) {
1328 		dev_err(&port->dev, "%s - usb_submit_urb(write bulk) failed "
1329 			"with status = %d\n", __func__, status);
1330 		bytes_sent = status;
1331 		goto exit;
1332 	}
1333 	bytes_sent = transfer_size;
1334 
1335 exit:
1336 	return bytes_sent;
1337 }
1338 
1339 static void mos7720_throttle(struct tty_struct *tty)
1340 {
1341 	struct usb_serial_port *port = tty->driver_data;
1342 	struct moschip_port *mos7720_port;
1343 	int status;
1344 
1345 	dbg("%s- port %d", __func__, port->number);
1346 
1347 	mos7720_port = usb_get_serial_port_data(port);
1348 
1349 	if (mos7720_port == NULL)
1350 		return;
1351 
1352 	if (!mos7720_port->open) {
1353 		dbg("port not opened");
1354 		return;
1355 	}
1356 
1357 	dbg("%s: Entering ..........", __func__);
1358 
1359 	/* if we are implementing XON/XOFF, send the stop character */
1360 	if (I_IXOFF(tty)) {
1361 		unsigned char stop_char = STOP_CHAR(tty);
1362 		status = mos7720_write(tty, port, &stop_char, 1);
1363 		if (status <= 0)
1364 			return;
1365 	}
1366 
1367 	/* if we are implementing RTS/CTS, toggle that line */
1368 	if (tty->termios->c_cflag & CRTSCTS) {
1369 		mos7720_port->shadowMCR &= ~UART_MCR_RTS;
1370 		write_mos_reg(port->serial, port->number - port->serial->minor,
1371 			      MCR, mos7720_port->shadowMCR);
1372 		if (status != 0)
1373 			return;
1374 	}
1375 }
1376 
1377 static void mos7720_unthrottle(struct tty_struct *tty)
1378 {
1379 	struct usb_serial_port *port = tty->driver_data;
1380 	struct moschip_port *mos7720_port = usb_get_serial_port_data(port);
1381 	int status;
1382 
1383 	if (mos7720_port == NULL)
1384 		return;
1385 
1386 	if (!mos7720_port->open) {
1387 		dbg("%s - port not opened", __func__);
1388 		return;
1389 	}
1390 
1391 	dbg("%s: Entering ..........", __func__);
1392 
1393 	/* if we are implementing XON/XOFF, send the start character */
1394 	if (I_IXOFF(tty)) {
1395 		unsigned char start_char = START_CHAR(tty);
1396 		status = mos7720_write(tty, port, &start_char, 1);
1397 		if (status <= 0)
1398 			return;
1399 	}
1400 
1401 	/* if we are implementing RTS/CTS, toggle that line */
1402 	if (tty->termios->c_cflag & CRTSCTS) {
1403 		mos7720_port->shadowMCR |= UART_MCR_RTS;
1404 		write_mos_reg(port->serial, port->number - port->serial->minor,
1405 			      MCR, mos7720_port->shadowMCR);
1406 		if (status != 0)
1407 			return;
1408 	}
1409 }
1410 
1411 /* FIXME: this function does not work */
1412 static int set_higher_rates(struct moschip_port *mos7720_port,
1413 			    unsigned int baud)
1414 {
1415 	struct usb_serial_port *port;
1416 	struct usb_serial *serial;
1417 	int port_number;
1418 	enum mos_regs sp_reg;
1419 	if (mos7720_port == NULL)
1420 		return -EINVAL;
1421 
1422 	port = mos7720_port->port;
1423 	serial = port->serial;
1424 
1425 	 /***********************************************
1426 	 *      Init Sequence for higher rates
1427 	 ***********************************************/
1428 	dbg("Sending Setting Commands ..........");
1429 	port_number = port->number - port->serial->minor;
1430 
1431 	write_mos_reg(serial, port_number, IER, 0x00);
1432 	write_mos_reg(serial, port_number, FCR, 0x00);
1433 	write_mos_reg(serial, port_number, FCR, 0xcf);
1434 	mos7720_port->shadowMCR = 0x0b;
1435 	write_mos_reg(serial, port_number, MCR, mos7720_port->shadowMCR);
1436 	write_mos_reg(serial, dummy, SP_CONTROL_REG, 0x00);
1437 
1438 	/***********************************************
1439 	 *              Set for higher rates           *
1440 	 ***********************************************/
1441 	/* writing baud rate verbatum into uart clock field clearly not right */
1442 	if (port_number == 0)
1443 		sp_reg = SP1_REG;
1444 	else
1445 		sp_reg = SP2_REG;
1446 	write_mos_reg(serial, dummy, sp_reg, baud * 0x10);
1447 	write_mos_reg(serial, dummy, SP_CONTROL_REG, 0x03);
1448 	mos7720_port->shadowMCR = 0x2b;
1449 	write_mos_reg(serial, port_number, MCR, mos7720_port->shadowMCR);
1450 
1451 	/***********************************************
1452 	 *              Set DLL/DLM
1453 	 ***********************************************/
1454 	mos7720_port->shadowLCR = mos7720_port->shadowLCR | UART_LCR_DLAB;
1455 	write_mos_reg(serial, port_number, LCR, mos7720_port->shadowLCR);
1456 	write_mos_reg(serial, port_number, DLL, 0x01);
1457 	write_mos_reg(serial, port_number, DLM, 0x00);
1458 	mos7720_port->shadowLCR = mos7720_port->shadowLCR & ~UART_LCR_DLAB;
1459 	write_mos_reg(serial, port_number, LCR, mos7720_port->shadowLCR);
1460 
1461 	return 0;
1462 }
1463 
1464 /* baud rate information */
1465 struct divisor_table_entry {
1466 	__u32  baudrate;
1467 	__u16  divisor;
1468 };
1469 
1470 /* Define table of divisors for moschip 7720 hardware	   *
1471  * These assume a 3.6864MHz crystal, the standard /16, and *
1472  * MCR.7 = 0.						   */
1473 static struct divisor_table_entry divisor_table[] = {
1474 	{   50,		2304},
1475 	{   110,	1047},	/* 2094.545455 => 230450   => .0217 % over */
1476 	{   134,	857},	/* 1713.011152 => 230398.5 => .00065% under */
1477 	{   150,	768},
1478 	{   300,	384},
1479 	{   600,	192},
1480 	{   1200,	96},
1481 	{   1800,	64},
1482 	{   2400,	48},
1483 	{   4800,	24},
1484 	{   7200,	16},
1485 	{   9600,	12},
1486 	{   19200,	6},
1487 	{   38400,	3},
1488 	{   57600,	2},
1489 	{   115200,	1},
1490 };
1491 
1492 /*****************************************************************************
1493  * calc_baud_rate_divisor
1494  *	this function calculates the proper baud rate divisor for the specified
1495  *	baud rate.
1496  *****************************************************************************/
1497 static int calc_baud_rate_divisor(int baudrate, int *divisor)
1498 {
1499 	int i;
1500 	__u16 custom;
1501 	__u16 round1;
1502 	__u16 round;
1503 
1504 
1505 	dbg("%s - %d", __func__, baudrate);
1506 
1507 	for (i = 0; i < ARRAY_SIZE(divisor_table); i++) {
1508 		if (divisor_table[i].baudrate == baudrate) {
1509 			*divisor = divisor_table[i].divisor;
1510 			return 0;
1511 		}
1512 	}
1513 
1514 	/* After trying for all the standard baud rates    *
1515 	 * Try calculating the divisor for this baud rate  */
1516 	if (baudrate > 75 &&  baudrate < 230400) {
1517 		/* get the divisor */
1518 		custom = (__u16)(230400L  / baudrate);
1519 
1520 		/* Check for round off */
1521 		round1 = (__u16)(2304000L / baudrate);
1522 		round = (__u16)(round1 - (custom * 10));
1523 		if (round > 4)
1524 			custom++;
1525 		*divisor = custom;
1526 
1527 		dbg("Baud %d = %d", baudrate, custom);
1528 		return 0;
1529 	}
1530 
1531 	dbg("Baud calculation Failed...");
1532 	return -EINVAL;
1533 }
1534 
1535 /*
1536  * send_cmd_write_baud_rate
1537  *	this function sends the proper command to change the baud rate of the
1538  *	specified port.
1539  */
1540 static int send_cmd_write_baud_rate(struct moschip_port *mos7720_port,
1541 				    int baudrate)
1542 {
1543 	struct usb_serial_port *port;
1544 	struct usb_serial *serial;
1545 	int divisor;
1546 	int status;
1547 	unsigned char number;
1548 
1549 	if (mos7720_port == NULL)
1550 		return -1;
1551 
1552 	port = mos7720_port->port;
1553 	serial = port->serial;
1554 
1555 	dbg("%s: Entering ..........", __func__);
1556 
1557 	number = port->number - port->serial->minor;
1558 	dbg("%s - port = %d, baud = %d", __func__, port->number, baudrate);
1559 
1560 	/* Calculate the Divisor */
1561 	status = calc_baud_rate_divisor(baudrate, &divisor);
1562 	if (status) {
1563 		dev_err(&port->dev, "%s - bad baud rate\n", __func__);
1564 		return status;
1565 	}
1566 
1567 	/* Enable access to divisor latch */
1568 	mos7720_port->shadowLCR = mos7720_port->shadowLCR | UART_LCR_DLAB;
1569 	write_mos_reg(serial, number, LCR, mos7720_port->shadowLCR);
1570 
1571 	/* Write the divisor */
1572 	write_mos_reg(serial, number, DLL, (__u8)(divisor & 0xff));
1573 	write_mos_reg(serial, number, DLM, (__u8)((divisor & 0xff00) >> 8));
1574 
1575 	/* Disable access to divisor latch */
1576 	mos7720_port->shadowLCR = mos7720_port->shadowLCR & ~UART_LCR_DLAB;
1577 	write_mos_reg(serial, number, LCR, mos7720_port->shadowLCR);
1578 
1579 	return status;
1580 }
1581 
1582 /*
1583  * change_port_settings
1584  *	This routine is called to set the UART on the device to match
1585  *      the specified new settings.
1586  */
1587 static void change_port_settings(struct tty_struct *tty,
1588 				 struct moschip_port *mos7720_port,
1589 				 struct ktermios *old_termios)
1590 {
1591 	struct usb_serial_port *port;
1592 	struct usb_serial *serial;
1593 	int baud;
1594 	unsigned cflag;
1595 	unsigned iflag;
1596 	__u8 mask = 0xff;
1597 	__u8 lData;
1598 	__u8 lParity;
1599 	__u8 lStop;
1600 	int status;
1601 	int port_number;
1602 
1603 	if (mos7720_port == NULL)
1604 		return ;
1605 
1606 	port = mos7720_port->port;
1607 	serial = port->serial;
1608 	port_number = port->number - port->serial->minor;
1609 
1610 	dbg("%s - port %d", __func__, port->number);
1611 
1612 	if (!mos7720_port->open) {
1613 		dbg("%s - port not opened", __func__);
1614 		return;
1615 	}
1616 
1617 	dbg("%s: Entering ..........", __func__);
1618 
1619 	lData = UART_LCR_WLEN8;
1620 	lStop = 0x00;	/* 1 stop bit */
1621 	lParity = 0x00;	/* No parity */
1622 
1623 	cflag = tty->termios->c_cflag;
1624 	iflag = tty->termios->c_iflag;
1625 
1626 	/* Change the number of bits */
1627 	switch (cflag & CSIZE) {
1628 	case CS5:
1629 		lData = UART_LCR_WLEN5;
1630 		mask = 0x1f;
1631 		break;
1632 
1633 	case CS6:
1634 		lData = UART_LCR_WLEN6;
1635 		mask = 0x3f;
1636 		break;
1637 
1638 	case CS7:
1639 		lData = UART_LCR_WLEN7;
1640 		mask = 0x7f;
1641 		break;
1642 	default:
1643 	case CS8:
1644 		lData = UART_LCR_WLEN8;
1645 		break;
1646 	}
1647 
1648 	/* Change the Parity bit */
1649 	if (cflag & PARENB) {
1650 		if (cflag & PARODD) {
1651 			lParity = UART_LCR_PARITY;
1652 			dbg("%s - parity = odd", __func__);
1653 		} else {
1654 			lParity = (UART_LCR_EPAR | UART_LCR_PARITY);
1655 			dbg("%s - parity = even", __func__);
1656 		}
1657 
1658 	} else {
1659 		dbg("%s - parity = none", __func__);
1660 	}
1661 
1662 	if (cflag & CMSPAR)
1663 		lParity = lParity | 0x20;
1664 
1665 	/* Change the Stop bit */
1666 	if (cflag & CSTOPB) {
1667 		lStop = UART_LCR_STOP;
1668 		dbg("%s - stop bits = 2", __func__);
1669 	} else {
1670 		lStop = 0x00;
1671 		dbg("%s - stop bits = 1", __func__);
1672 	}
1673 
1674 #define LCR_BITS_MASK		0x03	/* Mask for bits/char field */
1675 #define LCR_STOP_MASK		0x04	/* Mask for stop bits field */
1676 #define LCR_PAR_MASK		0x38	/* Mask for parity field */
1677 
1678 	/* Update the LCR with the correct value */
1679 	mos7720_port->shadowLCR &=
1680 		~(LCR_BITS_MASK | LCR_STOP_MASK | LCR_PAR_MASK);
1681 	mos7720_port->shadowLCR |= (lData | lParity | lStop);
1682 
1683 
1684 	/* Disable Interrupts */
1685 	write_mos_reg(serial, port_number, IER, 0x00);
1686 	write_mos_reg(serial, port_number, FCR, 0x00);
1687 	write_mos_reg(serial, port_number, FCR, 0xcf);
1688 
1689 	/* Send the updated LCR value to the mos7720 */
1690 	write_mos_reg(serial, port_number, LCR, mos7720_port->shadowLCR);
1691 	mos7720_port->shadowMCR = 0x0b;
1692 	write_mos_reg(serial, port_number, MCR, mos7720_port->shadowMCR);
1693 
1694 	/* set up the MCR register and send it to the mos7720 */
1695 	mos7720_port->shadowMCR = UART_MCR_OUT2;
1696 	if (cflag & CBAUD)
1697 		mos7720_port->shadowMCR |= (UART_MCR_DTR | UART_MCR_RTS);
1698 
1699 	if (cflag & CRTSCTS) {
1700 		mos7720_port->shadowMCR |= (UART_MCR_XONANY);
1701 		/* To set hardware flow control to the specified *
1702 		 * serial port, in SP1/2_CONTROL_REG             */
1703 		if (port->number)
1704 			write_mos_reg(serial, dummy, SP_CONTROL_REG, 0x01);
1705 		else
1706 			write_mos_reg(serial, dummy, SP_CONTROL_REG, 0x02);
1707 
1708 	} else
1709 		mos7720_port->shadowMCR &= ~(UART_MCR_XONANY);
1710 
1711 	write_mos_reg(serial, port_number, MCR, mos7720_port->shadowMCR);
1712 
1713 	/* Determine divisor based on baud rate */
1714 	baud = tty_get_baud_rate(tty);
1715 	if (!baud) {
1716 		/* pick a default, any default... */
1717 		dbg("Picked default baud...");
1718 		baud = 9600;
1719 	}
1720 
1721 	if (baud >= 230400) {
1722 		set_higher_rates(mos7720_port, baud);
1723 		/* Enable Interrupts */
1724 		write_mos_reg(serial, port_number, IER, 0x0c);
1725 		return;
1726 	}
1727 
1728 	dbg("%s - baud rate = %d", __func__, baud);
1729 	status = send_cmd_write_baud_rate(mos7720_port, baud);
1730 	/* FIXME: needs to write actual resulting baud back not just
1731 	   blindly do so */
1732 	if (cflag & CBAUD)
1733 		tty_encode_baud_rate(tty, baud, baud);
1734 	/* Enable Interrupts */
1735 	write_mos_reg(serial, port_number, IER, 0x0c);
1736 
1737 	if (port->read_urb->status != -EINPROGRESS) {
1738 		port->read_urb->dev = serial->dev;
1739 
1740 		status = usb_submit_urb(port->read_urb, GFP_ATOMIC);
1741 		if (status)
1742 			dbg("usb_submit_urb(read bulk) failed, status = %d",
1743 			    status);
1744 	}
1745 }
1746 
1747 /*
1748  * mos7720_set_termios
1749  *	this function is called by the tty driver when it wants to change the
1750  *	termios structure.
1751  */
1752 static void mos7720_set_termios(struct tty_struct *tty,
1753 		struct usb_serial_port *port, struct ktermios *old_termios)
1754 {
1755 	int status;
1756 	unsigned int cflag;
1757 	struct usb_serial *serial;
1758 	struct moschip_port *mos7720_port;
1759 
1760 	serial = port->serial;
1761 
1762 	mos7720_port = usb_get_serial_port_data(port);
1763 
1764 	if (mos7720_port == NULL)
1765 		return;
1766 
1767 	if (!mos7720_port->open) {
1768 		dbg("%s - port not opened", __func__);
1769 		return;
1770 	}
1771 
1772 	dbg("%s\n", "setting termios - ASPIRE");
1773 
1774 	cflag = tty->termios->c_cflag;
1775 
1776 	dbg("%s - cflag %08x iflag %08x", __func__,
1777 	    tty->termios->c_cflag,
1778 	    RELEVANT_IFLAG(tty->termios->c_iflag));
1779 
1780 	dbg("%s - old cflag %08x old iflag %08x", __func__,
1781 	    old_termios->c_cflag,
1782 	    RELEVANT_IFLAG(old_termios->c_iflag));
1783 
1784 	dbg("%s - port %d", __func__, port->number);
1785 
1786 	/* change the port settings to the new ones specified */
1787 	change_port_settings(tty, mos7720_port, old_termios);
1788 
1789 	if (!port->read_urb) {
1790 		dbg("%s", "URB KILLED !!!!!");
1791 		return;
1792 	}
1793 
1794 	if (port->read_urb->status != -EINPROGRESS) {
1795 		port->read_urb->dev = serial->dev;
1796 		status = usb_submit_urb(port->read_urb, GFP_ATOMIC);
1797 		if (status)
1798 			dbg("usb_submit_urb(read bulk) failed, status = %d",
1799 			    status);
1800 	}
1801 }
1802 
1803 /*
1804  * get_lsr_info - get line status register info
1805  *
1806  * Purpose: Let user call ioctl() to get info when the UART physically
1807  * 	    is emptied.  On bus types like RS485, the transmitter must
1808  * 	    release the bus after transmitting. This must be done when
1809  * 	    the transmit shift register is empty, not be done when the
1810  * 	    transmit holding register is empty.  This functionality
1811  * 	    allows an RS485 driver to be written in user space.
1812  */
1813 static int get_lsr_info(struct tty_struct *tty,
1814 		struct moschip_port *mos7720_port, unsigned int __user *value)
1815 {
1816 	struct usb_serial_port *port = tty->driver_data;
1817 	unsigned int result = 0;
1818 	unsigned char data = 0;
1819 	int port_number = port->number - port->serial->minor;
1820 	int count;
1821 
1822 	count = mos7720_chars_in_buffer(tty);
1823 	if (count == 0) {
1824 		read_mos_reg(port->serial, port_number, LSR, &data);
1825 		if ((data & (UART_LSR_TEMT | UART_LSR_THRE))
1826 					== (UART_LSR_TEMT | UART_LSR_THRE)) {
1827 			dbg("%s -- Empty", __func__);
1828 			result = TIOCSER_TEMT;
1829 		}
1830 	}
1831 	if (copy_to_user(value, &result, sizeof(int)))
1832 		return -EFAULT;
1833 	return 0;
1834 }
1835 
1836 static int mos7720_tiocmget(struct tty_struct *tty)
1837 {
1838 	struct usb_serial_port *port = tty->driver_data;
1839 	struct moschip_port *mos7720_port = usb_get_serial_port_data(port);
1840 	unsigned int result = 0;
1841 	unsigned int mcr ;
1842 	unsigned int msr ;
1843 
1844 	dbg("%s - port %d", __func__, port->number);
1845 
1846 	mcr = mos7720_port->shadowMCR;
1847 	msr = mos7720_port->shadowMSR;
1848 
1849 	result = ((mcr & UART_MCR_DTR)  ? TIOCM_DTR : 0)   /* 0x002 */
1850 	  | ((mcr & UART_MCR_RTS)   ? TIOCM_RTS : 0)   /* 0x004 */
1851 	  | ((msr & UART_MSR_CTS)   ? TIOCM_CTS : 0)   /* 0x020 */
1852 	  | ((msr & UART_MSR_DCD)   ? TIOCM_CAR : 0)   /* 0x040 */
1853 	  | ((msr & UART_MSR_RI)    ? TIOCM_RI :  0)   /* 0x080 */
1854 	  | ((msr & UART_MSR_DSR)   ? TIOCM_DSR : 0);  /* 0x100 */
1855 
1856 	dbg("%s -- %x", __func__, result);
1857 
1858 	return result;
1859 }
1860 
1861 static int mos7720_tiocmset(struct tty_struct *tty,
1862 			    unsigned int set, unsigned int clear)
1863 {
1864 	struct usb_serial_port *port = tty->driver_data;
1865 	struct moschip_port *mos7720_port = usb_get_serial_port_data(port);
1866 	unsigned int mcr ;
1867 	dbg("%s - port %d", __func__, port->number);
1868 	dbg("he was at tiocmset");
1869 
1870 	mcr = mos7720_port->shadowMCR;
1871 
1872 	if (set & TIOCM_RTS)
1873 		mcr |= UART_MCR_RTS;
1874 	if (set & TIOCM_DTR)
1875 		mcr |= UART_MCR_DTR;
1876 	if (set & TIOCM_LOOP)
1877 		mcr |= UART_MCR_LOOP;
1878 
1879 	if (clear & TIOCM_RTS)
1880 		mcr &= ~UART_MCR_RTS;
1881 	if (clear & TIOCM_DTR)
1882 		mcr &= ~UART_MCR_DTR;
1883 	if (clear & TIOCM_LOOP)
1884 		mcr &= ~UART_MCR_LOOP;
1885 
1886 	mos7720_port->shadowMCR = mcr;
1887 	write_mos_reg(port->serial, port->number - port->serial->minor,
1888 		      MCR, mos7720_port->shadowMCR);
1889 
1890 	return 0;
1891 }
1892 
1893 static int mos7720_get_icount(struct tty_struct *tty,
1894 				struct serial_icounter_struct *icount)
1895 {
1896 	struct usb_serial_port *port = tty->driver_data;
1897 	struct moschip_port *mos7720_port;
1898 	struct async_icount cnow;
1899 
1900 	mos7720_port = usb_get_serial_port_data(port);
1901 	cnow = mos7720_port->icount;
1902 
1903 	icount->cts = cnow.cts;
1904 	icount->dsr = cnow.dsr;
1905 	icount->rng = cnow.rng;
1906 	icount->dcd = cnow.dcd;
1907 	icount->rx = cnow.rx;
1908 	icount->tx = cnow.tx;
1909 	icount->frame = cnow.frame;
1910 	icount->overrun = cnow.overrun;
1911 	icount->parity = cnow.parity;
1912 	icount->brk = cnow.brk;
1913 	icount->buf_overrun = cnow.buf_overrun;
1914 
1915 	dbg("%s (%d) TIOCGICOUNT RX=%d, TX=%d", __func__,
1916 		port->number, icount->rx, icount->tx);
1917 	return 0;
1918 }
1919 
1920 static int set_modem_info(struct moschip_port *mos7720_port, unsigned int cmd,
1921 			  unsigned int __user *value)
1922 {
1923 	unsigned int mcr;
1924 	unsigned int arg;
1925 
1926 	struct usb_serial_port *port;
1927 
1928 	if (mos7720_port == NULL)
1929 		return -1;
1930 
1931 	port = (struct usb_serial_port *)mos7720_port->port;
1932 	mcr = mos7720_port->shadowMCR;
1933 
1934 	if (copy_from_user(&arg, value, sizeof(int)))
1935 		return -EFAULT;
1936 
1937 	switch (cmd) {
1938 	case TIOCMBIS:
1939 		if (arg & TIOCM_RTS)
1940 			mcr |= UART_MCR_RTS;
1941 		if (arg & TIOCM_DTR)
1942 			mcr |= UART_MCR_RTS;
1943 		if (arg & TIOCM_LOOP)
1944 			mcr |= UART_MCR_LOOP;
1945 		break;
1946 
1947 	case TIOCMBIC:
1948 		if (arg & TIOCM_RTS)
1949 			mcr &= ~UART_MCR_RTS;
1950 		if (arg & TIOCM_DTR)
1951 			mcr &= ~UART_MCR_RTS;
1952 		if (arg & TIOCM_LOOP)
1953 			mcr &= ~UART_MCR_LOOP;
1954 		break;
1955 
1956 	}
1957 
1958 	mos7720_port->shadowMCR = mcr;
1959 	write_mos_reg(port->serial, port->number - port->serial->minor,
1960 		      MCR, mos7720_port->shadowMCR);
1961 
1962 	return 0;
1963 }
1964 
1965 static int get_serial_info(struct moschip_port *mos7720_port,
1966 			   struct serial_struct __user *retinfo)
1967 {
1968 	struct serial_struct tmp;
1969 
1970 	if (!retinfo)
1971 		return -EFAULT;
1972 
1973 	memset(&tmp, 0, sizeof(tmp));
1974 
1975 	tmp.type		= PORT_16550A;
1976 	tmp.line		= mos7720_port->port->serial->minor;
1977 	tmp.port		= mos7720_port->port->number;
1978 	tmp.irq			= 0;
1979 	tmp.flags		= ASYNC_SKIP_TEST | ASYNC_AUTO_IRQ;
1980 	tmp.xmit_fifo_size	= NUM_URBS * URB_TRANSFER_BUFFER_SIZE;
1981 	tmp.baud_base		= 9600;
1982 	tmp.close_delay		= 5*HZ;
1983 	tmp.closing_wait	= 30*HZ;
1984 
1985 	if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
1986 		return -EFAULT;
1987 	return 0;
1988 }
1989 
1990 static int mos7720_ioctl(struct tty_struct *tty,
1991 			 unsigned int cmd, unsigned long arg)
1992 {
1993 	struct usb_serial_port *port = tty->driver_data;
1994 	struct moschip_port *mos7720_port;
1995 	struct async_icount cnow;
1996 	struct async_icount cprev;
1997 
1998 	mos7720_port = usb_get_serial_port_data(port);
1999 	if (mos7720_port == NULL)
2000 		return -ENODEV;
2001 
2002 	dbg("%s - port %d, cmd = 0x%x", __func__, port->number, cmd);
2003 
2004 	switch (cmd) {
2005 	case TIOCSERGETLSR:
2006 		dbg("%s (%d) TIOCSERGETLSR", __func__,  port->number);
2007 		return get_lsr_info(tty, mos7720_port,
2008 					(unsigned int __user *)arg);
2009 
2010 	/* FIXME: These should be using the mode methods */
2011 	case TIOCMBIS:
2012 	case TIOCMBIC:
2013 		dbg("%s (%d) TIOCMSET/TIOCMBIC/TIOCMSET",
2014 					__func__, port->number);
2015 		return set_modem_info(mos7720_port, cmd,
2016 				      (unsigned int __user *)arg);
2017 
2018 	case TIOCGSERIAL:
2019 		dbg("%s (%d) TIOCGSERIAL", __func__,  port->number);
2020 		return get_serial_info(mos7720_port,
2021 				       (struct serial_struct __user *)arg);
2022 
2023 	case TIOCMIWAIT:
2024 		dbg("%s (%d) TIOCMIWAIT", __func__,  port->number);
2025 		cprev = mos7720_port->icount;
2026 		while (1) {
2027 			if (signal_pending(current))
2028 				return -ERESTARTSYS;
2029 			cnow = mos7720_port->icount;
2030 			if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
2031 			    cnow.dcd == cprev.dcd && cnow.cts == cprev.cts)
2032 				return -EIO; /* no change => error */
2033 			if (((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) ||
2034 			    ((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) ||
2035 			    ((arg & TIOCM_CD)  && (cnow.dcd != cprev.dcd)) ||
2036 			    ((arg & TIOCM_CTS) && (cnow.cts != cprev.cts))) {
2037 				return 0;
2038 			}
2039 			cprev = cnow;
2040 		}
2041 		/* NOTREACHED */
2042 		break;
2043 	}
2044 
2045 	return -ENOIOCTLCMD;
2046 }
2047 
2048 static int mos7720_startup(struct usb_serial *serial)
2049 {
2050 	struct moschip_port *mos7720_port;
2051 	struct usb_device *dev;
2052 	int i;
2053 	char data;
2054 	u16 product;
2055 	int ret_val;
2056 
2057 	dbg("%s: Entering ..........", __func__);
2058 
2059 	if (!serial) {
2060 		dbg("Invalid Handler");
2061 		return -ENODEV;
2062 	}
2063 
2064 	product = le16_to_cpu(serial->dev->descriptor.idProduct);
2065 	dev = serial->dev;
2066 
2067 	/*
2068 	 * The 7715 uses the first bulk in/out endpoint pair for the parallel
2069 	 * port, and the second for the serial port.  Because the usbserial core
2070 	 * assumes both pairs are serial ports, we must engage in a bit of
2071 	 * subterfuge and swap the pointers for ports 0 and 1 in order to make
2072 	 * port 0 point to the serial port.  However, both moschip devices use a
2073 	 * single interrupt-in endpoint for both ports (as mentioned a little
2074 	 * further down), and this endpoint was assigned to port 0.  So after
2075 	 * the swap, we must copy the interrupt endpoint elements from port 1
2076 	 * (as newly assigned) to port 0, and null out port 1 pointers.
2077 	 */
2078 	if (product == MOSCHIP_DEVICE_ID_7715) {
2079 		struct usb_serial_port *tmp = serial->port[0];
2080 		serial->port[0] = serial->port[1];
2081 		serial->port[1] = tmp;
2082 		serial->port[0]->interrupt_in_urb = tmp->interrupt_in_urb;
2083 		serial->port[0]->interrupt_in_buffer = tmp->interrupt_in_buffer;
2084 		serial->port[0]->interrupt_in_endpointAddress =
2085 			tmp->interrupt_in_endpointAddress;
2086 		serial->port[1]->interrupt_in_urb = NULL;
2087 		serial->port[1]->interrupt_in_buffer = NULL;
2088 	}
2089 
2090 
2091 	/* set up serial port private structures */
2092 	for (i = 0; i < serial->num_ports; ++i) {
2093 		mos7720_port = kzalloc(sizeof(struct moschip_port), GFP_KERNEL);
2094 		if (mos7720_port == NULL) {
2095 			dev_err(&dev->dev, "%s - Out of memory\n", __func__);
2096 			return -ENOMEM;
2097 		}
2098 
2099 		/* Initialize all port interrupt end point to port 0 int
2100 		 * endpoint.  Our device has only one interrupt endpoint
2101 		 * common to all ports */
2102 		serial->port[i]->interrupt_in_endpointAddress =
2103 				serial->port[0]->interrupt_in_endpointAddress;
2104 
2105 		mos7720_port->port = serial->port[i];
2106 		usb_set_serial_port_data(serial->port[i], mos7720_port);
2107 
2108 		dbg("port number is %d", serial->port[i]->number);
2109 		dbg("serial number is %d", serial->minor);
2110 	}
2111 
2112 
2113 	/* setting configuration feature to one */
2114 	usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
2115 			(__u8)0x03, 0x00, 0x01, 0x00, NULL, 0x00, 5*HZ);
2116 
2117 	/* start the interrupt urb */
2118 	ret_val = usb_submit_urb(serial->port[0]->interrupt_in_urb, GFP_KERNEL);
2119 	if (ret_val)
2120 		dev_err(&dev->dev,
2121 			"%s - Error %d submitting control urb\n",
2122 			__func__, ret_val);
2123 
2124 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
2125 	if (product == MOSCHIP_DEVICE_ID_7715) {
2126 		ret_val = mos7715_parport_init(serial);
2127 		if (ret_val < 0)
2128 			return ret_val;
2129 	}
2130 #endif
2131 	/* LSR For Port 1 */
2132 	read_mos_reg(serial, 0, LSR, &data);
2133 	dbg("LSR:%x", data);
2134 
2135 	return 0;
2136 }
2137 
2138 static void mos7720_release(struct usb_serial *serial)
2139 {
2140 	int i;
2141 
2142 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
2143 	/* close the parallel port */
2144 
2145 	if (le16_to_cpu(serial->dev->descriptor.idProduct)
2146 	    == MOSCHIP_DEVICE_ID_7715) {
2147 		struct urbtracker *urbtrack;
2148 		unsigned long flags;
2149 		struct mos7715_parport *mos_parport =
2150 			usb_get_serial_data(serial);
2151 
2152 		/* prevent NULL ptr dereference in port callbacks */
2153 		spin_lock(&release_lock);
2154 		mos_parport->pp->private_data = NULL;
2155 		spin_unlock(&release_lock);
2156 
2157 		/* wait for synchronous usb calls to return */
2158 		if (mos_parport->msg_pending)
2159 			wait_for_completion_timeout(&mos_parport->syncmsg_compl,
2160 						    MOS_WDR_TIMEOUT);
2161 
2162 		parport_remove_port(mos_parport->pp);
2163 		usb_set_serial_data(serial, NULL);
2164 		mos_parport->serial = NULL;
2165 
2166 		/* if tasklet currently scheduled, wait for it to complete */
2167 		tasklet_kill(&mos_parport->urb_tasklet);
2168 
2169 		/* unlink any urbs sent by the tasklet  */
2170 		spin_lock_irqsave(&mos_parport->listlock, flags);
2171 		list_for_each_entry(urbtrack,
2172 				    &mos_parport->active_urbs,
2173 				    urblist_entry)
2174 			usb_unlink_urb(urbtrack->urb);
2175 		spin_unlock_irqrestore(&mos_parport->listlock, flags);
2176 
2177 		kref_put(&mos_parport->ref_count, destroy_mos_parport);
2178 	}
2179 #endif
2180 	/* free private structure allocated for serial port */
2181 	for (i = 0; i < serial->num_ports; ++i)
2182 		kfree(usb_get_serial_port_data(serial->port[i]));
2183 }
2184 
2185 static struct usb_driver usb_driver = {
2186 	.name =		"moschip7720",
2187 	.probe =	usb_serial_probe,
2188 	.disconnect =	usb_serial_disconnect,
2189 	.id_table =	moschip_port_id_table,
2190 	.no_dynamic_id =	1,
2191 };
2192 
2193 static struct usb_serial_driver moschip7720_2port_driver = {
2194 	.driver = {
2195 		.owner =	THIS_MODULE,
2196 		.name =		"moschip7720",
2197 	},
2198 	.description		= "Moschip 2 port adapter",
2199 	.usb_driver		= &usb_driver,
2200 	.id_table		= moschip_port_id_table,
2201 	.calc_num_ports		= mos77xx_calc_num_ports,
2202 	.open			= mos7720_open,
2203 	.close			= mos7720_close,
2204 	.throttle		= mos7720_throttle,
2205 	.unthrottle		= mos7720_unthrottle,
2206 	.probe			= mos77xx_probe,
2207 	.attach			= mos7720_startup,
2208 	.release		= mos7720_release,
2209 	.ioctl			= mos7720_ioctl,
2210 	.tiocmget		= mos7720_tiocmget,
2211 	.tiocmset		= mos7720_tiocmset,
2212 	.get_icount		= mos7720_get_icount,
2213 	.set_termios		= mos7720_set_termios,
2214 	.write			= mos7720_write,
2215 	.write_room		= mos7720_write_room,
2216 	.chars_in_buffer	= mos7720_chars_in_buffer,
2217 	.break_ctl		= mos7720_break,
2218 	.read_bulk_callback	= mos7720_bulk_in_callback,
2219 	.read_int_callback	= NULL  /* dynamically assigned in probe() */
2220 };
2221 
2222 static int __init moschip7720_init(void)
2223 {
2224 	int retval;
2225 
2226 	dbg("%s: Entering ..........", __func__);
2227 
2228 	/* Register with the usb serial */
2229 	retval = usb_serial_register(&moschip7720_2port_driver);
2230 	if (retval)
2231 		goto failed_port_device_register;
2232 
2233 	printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
2234 	       DRIVER_DESC "\n");
2235 
2236 	/* Register with the usb */
2237 	retval = usb_register(&usb_driver);
2238 	if (retval)
2239 		goto failed_usb_register;
2240 
2241 	return 0;
2242 
2243 failed_usb_register:
2244 	usb_serial_deregister(&moschip7720_2port_driver);
2245 
2246 failed_port_device_register:
2247 	return retval;
2248 }
2249 
2250 static void __exit moschip7720_exit(void)
2251 {
2252 	usb_deregister(&usb_driver);
2253 	usb_serial_deregister(&moschip7720_2port_driver);
2254 }
2255 
2256 module_init(moschip7720_init);
2257 module_exit(moschip7720_exit);
2258 
2259 /* Module information */
2260 MODULE_AUTHOR(DRIVER_AUTHOR);
2261 MODULE_DESCRIPTION(DRIVER_DESC);
2262 MODULE_LICENSE("GPL");
2263 
2264 module_param(debug, bool, S_IRUGO | S_IWUSR);
2265 MODULE_PARM_DESC(debug, "Debug enabled or not");
2266