xref: /linux/drivers/usb/serial/mos7720.c (revision e58e871becec2d3b04ed91c0c16fe8deac9c9dfa)
1 /*
2  * mos7720.c
3  *   Controls the Moschip 7720 usb to dual port serial converter
4  *
5  * Copyright 2006 Moschip Semiconductor Tech. Ltd.
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation, version 2 of the License.
10  *
11  * Developed by:
12  * 	Vijaya Kumar <vijaykumar.gn@gmail.com>
13  *	Ajay Kumar <naanuajay@yahoo.com>
14  *	Gurudeva <ngurudeva@yahoo.com>
15  *
16  * Cleaned up from the original by:
17  *	Greg Kroah-Hartman <gregkh@suse.de>
18  *
19  * Originally based on drivers/usb/serial/io_edgeport.c which is:
20  *	Copyright (C) 2000 Inside Out Networks, All rights reserved.
21  *	Copyright (C) 2001-2002 Greg Kroah-Hartman <greg@kroah.com>
22  */
23 #include <linux/kernel.h>
24 #include <linux/errno.h>
25 #include <linux/slab.h>
26 #include <linux/tty.h>
27 #include <linux/tty_driver.h>
28 #include <linux/tty_flip.h>
29 #include <linux/module.h>
30 #include <linux/spinlock.h>
31 #include <linux/serial.h>
32 #include <linux/serial_reg.h>
33 #include <linux/usb.h>
34 #include <linux/usb/serial.h>
35 #include <linux/uaccess.h>
36 #include <linux/parport.h>
37 
38 #define DRIVER_AUTHOR "Aspire Communications pvt Ltd."
39 #define DRIVER_DESC "Moschip USB Serial Driver"
40 
41 /* default urb timeout */
42 #define MOS_WDR_TIMEOUT	5000
43 
44 #define MOS_MAX_PORT	0x02
45 #define MOS_WRITE	0x0E
46 #define MOS_READ	0x0D
47 
48 /* Interrupt Routines Defines	*/
49 #define SERIAL_IIR_RLS	0x06
50 #define SERIAL_IIR_RDA	0x04
51 #define SERIAL_IIR_CTI	0x0c
52 #define SERIAL_IIR_THR	0x02
53 #define SERIAL_IIR_MS	0x00
54 
55 #define NUM_URBS			16	/* URB Count */
56 #define URB_TRANSFER_BUFFER_SIZE	32	/* URB Size */
57 
58 /* This structure holds all of the local serial port information */
59 struct moschip_port {
60 	__u8	shadowLCR;		/* last LCR value received */
61 	__u8	shadowMCR;		/* last MCR value received */
62 	__u8	shadowMSR;		/* last MSR value received */
63 	char			open;
64 	struct usb_serial_port	*port;	/* loop back to the owner */
65 	struct urb		*write_urb_pool[NUM_URBS];
66 };
67 
68 #define USB_VENDOR_ID_MOSCHIP		0x9710
69 #define MOSCHIP_DEVICE_ID_7720		0x7720
70 #define MOSCHIP_DEVICE_ID_7715		0x7715
71 
72 static const struct usb_device_id id_table[] = {
73 	{ USB_DEVICE(USB_VENDOR_ID_MOSCHIP, MOSCHIP_DEVICE_ID_7720) },
74 	{ USB_DEVICE(USB_VENDOR_ID_MOSCHIP, MOSCHIP_DEVICE_ID_7715) },
75 	{ } /* terminating entry */
76 };
77 MODULE_DEVICE_TABLE(usb, id_table);
78 
79 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
80 
81 /* initial values for parport regs */
82 #define DCR_INIT_VAL       0x0c	/* SLCTIN, nINIT */
83 #define ECR_INIT_VAL       0x00	/* SPP mode */
84 
85 struct urbtracker {
86 	struct mos7715_parport  *mos_parport;
87 	struct list_head        urblist_entry;
88 	struct kref             ref_count;
89 	struct urb              *urb;
90 	struct usb_ctrlrequest	*setup;
91 };
92 
93 enum mos7715_pp_modes {
94 	SPP = 0<<5,
95 	PS2 = 1<<5,      /* moschip calls this 'NIBBLE' mode */
96 	PPF = 2<<5,	 /* moschip calls this 'CB-FIFO mode */
97 };
98 
99 struct mos7715_parport {
100 	struct parport          *pp;	       /* back to containing struct */
101 	struct kref             ref_count;     /* to instance of this struct */
102 	struct list_head        deferred_urbs; /* list deferred async urbs */
103 	struct list_head        active_urbs;   /* list async urbs in flight */
104 	spinlock_t              listlock;      /* protects list access */
105 	bool                    msg_pending;   /* usb sync call pending */
106 	struct completion       syncmsg_compl; /* usb sync call completed */
107 	struct tasklet_struct   urb_tasklet;   /* for sending deferred urbs */
108 	struct usb_serial       *serial;       /* back to containing struct */
109 	__u8	                shadowECR;     /* parallel port regs... */
110 	__u8	                shadowDCR;
111 	atomic_t                shadowDSR;     /* updated in int-in callback */
112 };
113 
114 /* lock guards against dereferencing NULL ptr in parport ops callbacks */
115 static DEFINE_SPINLOCK(release_lock);
116 
117 #endif	/* CONFIG_USB_SERIAL_MOS7715_PARPORT */
118 
119 static const unsigned int dummy; /* for clarity in register access fns */
120 
121 enum mos_regs {
122 	MOS7720_THR,		  /* serial port regs */
123 	MOS7720_RHR,
124 	MOS7720_IER,
125 	MOS7720_FCR,
126 	MOS7720_ISR,
127 	MOS7720_LCR,
128 	MOS7720_MCR,
129 	MOS7720_LSR,
130 	MOS7720_MSR,
131 	MOS7720_SPR,
132 	MOS7720_DLL,
133 	MOS7720_DLM,
134 	MOS7720_DPR,		  /* parallel port regs */
135 	MOS7720_DSR,
136 	MOS7720_DCR,
137 	MOS7720_ECR,
138 	MOS7720_SP1_REG,	  /* device control regs */
139 	MOS7720_SP2_REG,	  /* serial port 2 (7720 only) */
140 	MOS7720_PP_REG,
141 	MOS7720_SP_CONTROL_REG,
142 };
143 
144 /*
145  * Return the correct value for the Windex field of the setup packet
146  * for a control endpoint message.  See the 7715 datasheet.
147  */
148 static inline __u16 get_reg_index(enum mos_regs reg)
149 {
150 	static const __u16 mos7715_index_lookup_table[] = {
151 		0x00,		/* MOS7720_THR */
152 		0x00,		/* MOS7720_RHR */
153 		0x01,		/* MOS7720_IER */
154 		0x02,		/* MOS7720_FCR */
155 		0x02,		/* MOS7720_ISR */
156 		0x03,		/* MOS7720_LCR */
157 		0x04,		/* MOS7720_MCR */
158 		0x05,		/* MOS7720_LSR */
159 		0x06,		/* MOS7720_MSR */
160 		0x07,		/* MOS7720_SPR */
161 		0x00,		/* MOS7720_DLL */
162 		0x01,		/* MOS7720_DLM */
163 		0x00,		/* MOS7720_DPR */
164 		0x01,		/* MOS7720_DSR */
165 		0x02,		/* MOS7720_DCR */
166 		0x0a,		/* MOS7720_ECR */
167 		0x01,		/* MOS7720_SP1_REG */
168 		0x02,		/* MOS7720_SP2_REG (7720 only) */
169 		0x04,		/* MOS7720_PP_REG (7715 only) */
170 		0x08,		/* MOS7720_SP_CONTROL_REG */
171 	};
172 	return mos7715_index_lookup_table[reg];
173 }
174 
175 /*
176  * Return the correct value for the upper byte of the Wvalue field of
177  * the setup packet for a control endpoint message.
178  */
179 static inline __u16 get_reg_value(enum mos_regs reg,
180 				  unsigned int serial_portnum)
181 {
182 	if (reg >= MOS7720_SP1_REG)	/* control reg */
183 		return 0x0000;
184 
185 	else if (reg >= MOS7720_DPR)	/* parallel port reg (7715 only) */
186 		return 0x0100;
187 
188 	else			      /* serial port reg */
189 		return (serial_portnum + 2) << 8;
190 }
191 
192 /*
193  * Write data byte to the specified device register.  The data is embedded in
194  * the value field of the setup packet. serial_portnum is ignored for registers
195  * not specific to a particular serial port.
196  */
197 static int write_mos_reg(struct usb_serial *serial, unsigned int serial_portnum,
198 			 enum mos_regs reg, __u8 data)
199 {
200 	struct usb_device *usbdev = serial->dev;
201 	unsigned int pipe = usb_sndctrlpipe(usbdev, 0);
202 	__u8 request = (__u8)0x0e;
203 	__u8 requesttype = (__u8)0x40;
204 	__u16 index = get_reg_index(reg);
205 	__u16 value = get_reg_value(reg, serial_portnum) + data;
206 	int status = usb_control_msg(usbdev, pipe, request, requesttype, value,
207 				     index, NULL, 0, MOS_WDR_TIMEOUT);
208 	if (status < 0)
209 		dev_err(&usbdev->dev,
210 			"mos7720: usb_control_msg() failed: %d\n", status);
211 	return status;
212 }
213 
214 /*
215  * Read data byte from the specified device register.  The data returned by the
216  * device is embedded in the value field of the setup packet.  serial_portnum is
217  * ignored for registers that are not specific to a particular serial port.
218  */
219 static int read_mos_reg(struct usb_serial *serial, unsigned int serial_portnum,
220 			enum mos_regs reg, __u8 *data)
221 {
222 	struct usb_device *usbdev = serial->dev;
223 	unsigned int pipe = usb_rcvctrlpipe(usbdev, 0);
224 	__u8 request = (__u8)0x0d;
225 	__u8 requesttype = (__u8)0xc0;
226 	__u16 index = get_reg_index(reg);
227 	__u16 value = get_reg_value(reg, serial_portnum);
228 	u8 *buf;
229 	int status;
230 
231 	buf = kmalloc(1, GFP_KERNEL);
232 	if (!buf)
233 		return -ENOMEM;
234 
235 	status = usb_control_msg(usbdev, pipe, request, requesttype, value,
236 				     index, buf, 1, MOS_WDR_TIMEOUT);
237 	if (status == 1) {
238 		*data = *buf;
239 	} else {
240 		dev_err(&usbdev->dev,
241 			"mos7720: usb_control_msg() failed: %d\n", status);
242 		if (status >= 0)
243 			status = -EIO;
244 		*data = 0;
245 	}
246 
247 	kfree(buf);
248 
249 	return status;
250 }
251 
252 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
253 
254 static inline int mos7715_change_mode(struct mos7715_parport *mos_parport,
255 				      enum mos7715_pp_modes mode)
256 {
257 	mos_parport->shadowECR = mode;
258 	write_mos_reg(mos_parport->serial, dummy, MOS7720_ECR,
259 		      mos_parport->shadowECR);
260 	return 0;
261 }
262 
263 static void destroy_mos_parport(struct kref *kref)
264 {
265 	struct mos7715_parport *mos_parport =
266 		container_of(kref, struct mos7715_parport, ref_count);
267 
268 	kfree(mos_parport);
269 }
270 
271 static void destroy_urbtracker(struct kref *kref)
272 {
273 	struct urbtracker *urbtrack =
274 		container_of(kref, struct urbtracker, ref_count);
275 	struct mos7715_parport *mos_parport = urbtrack->mos_parport;
276 
277 	usb_free_urb(urbtrack->urb);
278 	kfree(urbtrack->setup);
279 	kfree(urbtrack);
280 	kref_put(&mos_parport->ref_count, destroy_mos_parport);
281 }
282 
283 /*
284  * This runs as a tasklet when sending an urb in a non-blocking parallel
285  * port callback had to be deferred because the disconnect mutex could not be
286  * obtained at the time.
287  */
288 static void send_deferred_urbs(unsigned long _mos_parport)
289 {
290 	int ret_val;
291 	unsigned long flags;
292 	struct mos7715_parport *mos_parport = (void *)_mos_parport;
293 	struct urbtracker *urbtrack, *tmp;
294 	struct list_head *cursor, *next;
295 	struct device *dev;
296 
297 	/* if release function ran, game over */
298 	if (unlikely(mos_parport->serial == NULL))
299 		return;
300 
301 	dev = &mos_parport->serial->dev->dev;
302 
303 	/* try again to get the mutex */
304 	if (!mutex_trylock(&mos_parport->serial->disc_mutex)) {
305 		dev_dbg(dev, "%s: rescheduling tasklet\n", __func__);
306 		tasklet_schedule(&mos_parport->urb_tasklet);
307 		return;
308 	}
309 
310 	/* if device disconnected, game over */
311 	if (unlikely(mos_parport->serial->disconnected)) {
312 		mutex_unlock(&mos_parport->serial->disc_mutex);
313 		return;
314 	}
315 
316 	spin_lock_irqsave(&mos_parport->listlock, flags);
317 	if (list_empty(&mos_parport->deferred_urbs)) {
318 		spin_unlock_irqrestore(&mos_parport->listlock, flags);
319 		mutex_unlock(&mos_parport->serial->disc_mutex);
320 		dev_dbg(dev, "%s: deferred_urbs list empty\n", __func__);
321 		return;
322 	}
323 
324 	/* move contents of deferred_urbs list to active_urbs list and submit */
325 	list_for_each_safe(cursor, next, &mos_parport->deferred_urbs)
326 		list_move_tail(cursor, &mos_parport->active_urbs);
327 	list_for_each_entry_safe(urbtrack, tmp, &mos_parport->active_urbs,
328 			    urblist_entry) {
329 		ret_val = usb_submit_urb(urbtrack->urb, GFP_ATOMIC);
330 		dev_dbg(dev, "%s: urb submitted\n", __func__);
331 		if (ret_val) {
332 			dev_err(dev, "usb_submit_urb() failed: %d\n", ret_val);
333 			list_del(&urbtrack->urblist_entry);
334 			kref_put(&urbtrack->ref_count, destroy_urbtracker);
335 		}
336 	}
337 	spin_unlock_irqrestore(&mos_parport->listlock, flags);
338 	mutex_unlock(&mos_parport->serial->disc_mutex);
339 }
340 
341 /* callback for parallel port control urbs submitted asynchronously */
342 static void async_complete(struct urb *urb)
343 {
344 	struct urbtracker *urbtrack = urb->context;
345 	int status = urb->status;
346 
347 	if (unlikely(status))
348 		dev_dbg(&urb->dev->dev, "%s - nonzero urb status received: %d\n", __func__, status);
349 
350 	/* remove the urbtracker from the active_urbs list */
351 	spin_lock(&urbtrack->mos_parport->listlock);
352 	list_del(&urbtrack->urblist_entry);
353 	spin_unlock(&urbtrack->mos_parport->listlock);
354 	kref_put(&urbtrack->ref_count, destroy_urbtracker);
355 }
356 
357 static int write_parport_reg_nonblock(struct mos7715_parport *mos_parport,
358 				      enum mos_regs reg, __u8 data)
359 {
360 	struct urbtracker *urbtrack;
361 	int ret_val;
362 	unsigned long flags;
363 	struct usb_serial *serial = mos_parport->serial;
364 	struct usb_device *usbdev = serial->dev;
365 
366 	/* create and initialize the control urb and containing urbtracker */
367 	urbtrack = kmalloc(sizeof(struct urbtracker), GFP_ATOMIC);
368 	if (!urbtrack)
369 		return -ENOMEM;
370 
371 	kref_get(&mos_parport->ref_count);
372 	urbtrack->mos_parport = mos_parport;
373 	urbtrack->urb = usb_alloc_urb(0, GFP_ATOMIC);
374 	if (!urbtrack->urb) {
375 		kfree(urbtrack);
376 		return -ENOMEM;
377 	}
378 	urbtrack->setup = kmalloc(sizeof(*urbtrack->setup), GFP_ATOMIC);
379 	if (!urbtrack->setup) {
380 		usb_free_urb(urbtrack->urb);
381 		kfree(urbtrack);
382 		return -ENOMEM;
383 	}
384 	urbtrack->setup->bRequestType = (__u8)0x40;
385 	urbtrack->setup->bRequest = (__u8)0x0e;
386 	urbtrack->setup->wValue = cpu_to_le16(get_reg_value(reg, dummy));
387 	urbtrack->setup->wIndex = cpu_to_le16(get_reg_index(reg));
388 	urbtrack->setup->wLength = 0;
389 	usb_fill_control_urb(urbtrack->urb, usbdev,
390 			     usb_sndctrlpipe(usbdev, 0),
391 			     (unsigned char *)urbtrack->setup,
392 			     NULL, 0, async_complete, urbtrack);
393 	kref_init(&urbtrack->ref_count);
394 	INIT_LIST_HEAD(&urbtrack->urblist_entry);
395 
396 	/*
397 	 * get the disconnect mutex, or add tracker to the deferred_urbs list
398 	 * and schedule a tasklet to try again later
399 	 */
400 	if (!mutex_trylock(&serial->disc_mutex)) {
401 		spin_lock_irqsave(&mos_parport->listlock, flags);
402 		list_add_tail(&urbtrack->urblist_entry,
403 			      &mos_parport->deferred_urbs);
404 		spin_unlock_irqrestore(&mos_parport->listlock, flags);
405 		tasklet_schedule(&mos_parport->urb_tasklet);
406 		dev_dbg(&usbdev->dev, "tasklet scheduled\n");
407 		return 0;
408 	}
409 
410 	/* bail if device disconnected */
411 	if (serial->disconnected) {
412 		kref_put(&urbtrack->ref_count, destroy_urbtracker);
413 		mutex_unlock(&serial->disc_mutex);
414 		return -ENODEV;
415 	}
416 
417 	/* add the tracker to the active_urbs list and submit */
418 	spin_lock_irqsave(&mos_parport->listlock, flags);
419 	list_add_tail(&urbtrack->urblist_entry, &mos_parport->active_urbs);
420 	spin_unlock_irqrestore(&mos_parport->listlock, flags);
421 	ret_val = usb_submit_urb(urbtrack->urb, GFP_ATOMIC);
422 	mutex_unlock(&serial->disc_mutex);
423 	if (ret_val) {
424 		dev_err(&usbdev->dev,
425 			"%s: submit_urb() failed: %d\n", __func__, ret_val);
426 		spin_lock_irqsave(&mos_parport->listlock, flags);
427 		list_del(&urbtrack->urblist_entry);
428 		spin_unlock_irqrestore(&mos_parport->listlock, flags);
429 		kref_put(&urbtrack->ref_count, destroy_urbtracker);
430 		return ret_val;
431 	}
432 	return 0;
433 }
434 
435 /*
436  * This is the the common top part of all parallel port callback operations that
437  * send synchronous messages to the device.  This implements convoluted locking
438  * that avoids two scenarios: (1) a port operation is called after usbserial
439  * has called our release function, at which point struct mos7715_parport has
440  * been destroyed, and (2) the device has been disconnected, but usbserial has
441  * not called the release function yet because someone has a serial port open.
442  * The shared release_lock prevents the first, and the mutex and disconnected
443  * flag maintained by usbserial covers the second.  We also use the msg_pending
444  * flag to ensure that all synchronous usb message calls have completed before
445  * our release function can return.
446  */
447 static int parport_prologue(struct parport *pp)
448 {
449 	struct mos7715_parport *mos_parport;
450 
451 	spin_lock(&release_lock);
452 	mos_parport = pp->private_data;
453 	if (unlikely(mos_parport == NULL)) {
454 		/* release fn called, port struct destroyed */
455 		spin_unlock(&release_lock);
456 		return -1;
457 	}
458 	mos_parport->msg_pending = true;   /* synch usb call pending */
459 	reinit_completion(&mos_parport->syncmsg_compl);
460 	spin_unlock(&release_lock);
461 
462 	mutex_lock(&mos_parport->serial->disc_mutex);
463 	if (mos_parport->serial->disconnected) {
464 		/* device disconnected */
465 		mutex_unlock(&mos_parport->serial->disc_mutex);
466 		mos_parport->msg_pending = false;
467 		complete(&mos_parport->syncmsg_compl);
468 		return -1;
469 	}
470 
471 	return 0;
472 }
473 
474 /*
475  * This is the common bottom part of all parallel port functions that send
476  * synchronous messages to the device.
477  */
478 static inline void parport_epilogue(struct parport *pp)
479 {
480 	struct mos7715_parport *mos_parport = pp->private_data;
481 	mutex_unlock(&mos_parport->serial->disc_mutex);
482 	mos_parport->msg_pending = false;
483 	complete(&mos_parport->syncmsg_compl);
484 }
485 
486 static void parport_mos7715_write_data(struct parport *pp, unsigned char d)
487 {
488 	struct mos7715_parport *mos_parport = pp->private_data;
489 
490 	if (parport_prologue(pp) < 0)
491 		return;
492 	mos7715_change_mode(mos_parport, SPP);
493 	write_mos_reg(mos_parport->serial, dummy, MOS7720_DPR, (__u8)d);
494 	parport_epilogue(pp);
495 }
496 
497 static unsigned char parport_mos7715_read_data(struct parport *pp)
498 {
499 	struct mos7715_parport *mos_parport = pp->private_data;
500 	unsigned char d;
501 
502 	if (parport_prologue(pp) < 0)
503 		return 0;
504 	read_mos_reg(mos_parport->serial, dummy, MOS7720_DPR, &d);
505 	parport_epilogue(pp);
506 	return d;
507 }
508 
509 static void parport_mos7715_write_control(struct parport *pp, unsigned char d)
510 {
511 	struct mos7715_parport *mos_parport = pp->private_data;
512 	__u8 data;
513 
514 	if (parport_prologue(pp) < 0)
515 		return;
516 	data = ((__u8)d & 0x0f) | (mos_parport->shadowDCR & 0xf0);
517 	write_mos_reg(mos_parport->serial, dummy, MOS7720_DCR, data);
518 	mos_parport->shadowDCR = data;
519 	parport_epilogue(pp);
520 }
521 
522 static unsigned char parport_mos7715_read_control(struct parport *pp)
523 {
524 	struct mos7715_parport *mos_parport = pp->private_data;
525 	__u8 dcr;
526 
527 	spin_lock(&release_lock);
528 	mos_parport = pp->private_data;
529 	if (unlikely(mos_parport == NULL)) {
530 		spin_unlock(&release_lock);
531 		return 0;
532 	}
533 	dcr = mos_parport->shadowDCR & 0x0f;
534 	spin_unlock(&release_lock);
535 	return dcr;
536 }
537 
538 static unsigned char parport_mos7715_frob_control(struct parport *pp,
539 						  unsigned char mask,
540 						  unsigned char val)
541 {
542 	struct mos7715_parport *mos_parport = pp->private_data;
543 	__u8 dcr;
544 
545 	mask &= 0x0f;
546 	val &= 0x0f;
547 	if (parport_prologue(pp) < 0)
548 		return 0;
549 	mos_parport->shadowDCR = (mos_parport->shadowDCR & (~mask)) ^ val;
550 	write_mos_reg(mos_parport->serial, dummy, MOS7720_DCR,
551 		      mos_parport->shadowDCR);
552 	dcr = mos_parport->shadowDCR & 0x0f;
553 	parport_epilogue(pp);
554 	return dcr;
555 }
556 
557 static unsigned char parport_mos7715_read_status(struct parport *pp)
558 {
559 	unsigned char status;
560 	struct mos7715_parport *mos_parport = pp->private_data;
561 
562 	spin_lock(&release_lock);
563 	mos_parport = pp->private_data;
564 	if (unlikely(mos_parport == NULL)) {	/* release called */
565 		spin_unlock(&release_lock);
566 		return 0;
567 	}
568 	status = atomic_read(&mos_parport->shadowDSR) & 0xf8;
569 	spin_unlock(&release_lock);
570 	return status;
571 }
572 
573 static void parport_mos7715_enable_irq(struct parport *pp)
574 {
575 }
576 
577 static void parport_mos7715_disable_irq(struct parport *pp)
578 {
579 }
580 
581 static void parport_mos7715_data_forward(struct parport *pp)
582 {
583 	struct mos7715_parport *mos_parport = pp->private_data;
584 
585 	if (parport_prologue(pp) < 0)
586 		return;
587 	mos7715_change_mode(mos_parport, PS2);
588 	mos_parport->shadowDCR &=  ~0x20;
589 	write_mos_reg(mos_parport->serial, dummy, MOS7720_DCR,
590 		      mos_parport->shadowDCR);
591 	parport_epilogue(pp);
592 }
593 
594 static void parport_mos7715_data_reverse(struct parport *pp)
595 {
596 	struct mos7715_parport *mos_parport = pp->private_data;
597 
598 	if (parport_prologue(pp) < 0)
599 		return;
600 	mos7715_change_mode(mos_parport, PS2);
601 	mos_parport->shadowDCR |= 0x20;
602 	write_mos_reg(mos_parport->serial, dummy, MOS7720_DCR,
603 		      mos_parport->shadowDCR);
604 	parport_epilogue(pp);
605 }
606 
607 static void parport_mos7715_init_state(struct pardevice *dev,
608 				       struct parport_state *s)
609 {
610 	s->u.pc.ctr = DCR_INIT_VAL;
611 	s->u.pc.ecr = ECR_INIT_VAL;
612 }
613 
614 /* N.B. Parport core code requires that this function not block */
615 static void parport_mos7715_save_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 	s->u.pc.ctr = mos_parport->shadowDCR;
627 	s->u.pc.ecr = mos_parport->shadowECR;
628 	spin_unlock(&release_lock);
629 }
630 
631 /* N.B. Parport core code requires that this function not block */
632 static void parport_mos7715_restore_state(struct parport *pp,
633 					  struct parport_state *s)
634 {
635 	struct mos7715_parport *mos_parport;
636 
637 	spin_lock(&release_lock);
638 	mos_parport = pp->private_data;
639 	if (unlikely(mos_parport == NULL)) {	/* release called */
640 		spin_unlock(&release_lock);
641 		return;
642 	}
643 	write_parport_reg_nonblock(mos_parport, MOS7720_DCR,
644 				   mos_parport->shadowDCR);
645 	write_parport_reg_nonblock(mos_parport, MOS7720_ECR,
646 				   mos_parport->shadowECR);
647 	spin_unlock(&release_lock);
648 }
649 
650 static size_t parport_mos7715_write_compat(struct parport *pp,
651 					   const void *buffer,
652 					   size_t len, int flags)
653 {
654 	int retval;
655 	struct mos7715_parport *mos_parport = pp->private_data;
656 	int actual_len;
657 
658 	if (parport_prologue(pp) < 0)
659 		return 0;
660 	mos7715_change_mode(mos_parport, PPF);
661 	retval = usb_bulk_msg(mos_parport->serial->dev,
662 			      usb_sndbulkpipe(mos_parport->serial->dev, 2),
663 			      (void *)buffer, len, &actual_len,
664 			      MOS_WDR_TIMEOUT);
665 	parport_epilogue(pp);
666 	if (retval) {
667 		dev_err(&mos_parport->serial->dev->dev,
668 			"mos7720: usb_bulk_msg() failed: %d\n", retval);
669 		return 0;
670 	}
671 	return actual_len;
672 }
673 
674 static struct parport_operations parport_mos7715_ops = {
675 	.owner =		THIS_MODULE,
676 	.write_data =		parport_mos7715_write_data,
677 	.read_data =		parport_mos7715_read_data,
678 
679 	.write_control =	parport_mos7715_write_control,
680 	.read_control =		parport_mos7715_read_control,
681 	.frob_control =		parport_mos7715_frob_control,
682 
683 	.read_status =		parport_mos7715_read_status,
684 
685 	.enable_irq =		parport_mos7715_enable_irq,
686 	.disable_irq =		parport_mos7715_disable_irq,
687 
688 	.data_forward =		parport_mos7715_data_forward,
689 	.data_reverse =		parport_mos7715_data_reverse,
690 
691 	.init_state =		parport_mos7715_init_state,
692 	.save_state =		parport_mos7715_save_state,
693 	.restore_state =	parport_mos7715_restore_state,
694 
695 	.compat_write_data =	parport_mos7715_write_compat,
696 
697 	.nibble_read_data =	parport_ieee1284_read_nibble,
698 	.byte_read_data =	parport_ieee1284_read_byte,
699 };
700 
701 /*
702  * Allocate and initialize parallel port control struct, initialize
703  * the parallel port hardware device, and register with the parport subsystem.
704  */
705 static int mos7715_parport_init(struct usb_serial *serial)
706 {
707 	struct mos7715_parport *mos_parport;
708 
709 	/* allocate and initialize parallel port control struct */
710 	mos_parport = kzalloc(sizeof(struct mos7715_parport), GFP_KERNEL);
711 	if (!mos_parport)
712 		return -ENOMEM;
713 
714 	mos_parport->msg_pending = false;
715 	kref_init(&mos_parport->ref_count);
716 	spin_lock_init(&mos_parport->listlock);
717 	INIT_LIST_HEAD(&mos_parport->active_urbs);
718 	INIT_LIST_HEAD(&mos_parport->deferred_urbs);
719 	usb_set_serial_data(serial, mos_parport); /* hijack private pointer */
720 	mos_parport->serial = serial;
721 	tasklet_init(&mos_parport->urb_tasklet, send_deferred_urbs,
722 		     (unsigned long) mos_parport);
723 	init_completion(&mos_parport->syncmsg_compl);
724 
725 	/* cycle parallel port reset bit */
726 	write_mos_reg(mos_parport->serial, dummy, MOS7720_PP_REG, (__u8)0x80);
727 	write_mos_reg(mos_parport->serial, dummy, MOS7720_PP_REG, (__u8)0x00);
728 
729 	/* initialize device registers */
730 	mos_parport->shadowDCR = DCR_INIT_VAL;
731 	write_mos_reg(mos_parport->serial, dummy, MOS7720_DCR,
732 		      mos_parport->shadowDCR);
733 	mos_parport->shadowECR = ECR_INIT_VAL;
734 	write_mos_reg(mos_parport->serial, dummy, MOS7720_ECR,
735 		      mos_parport->shadowECR);
736 
737 	/* register with parport core */
738 	mos_parport->pp = parport_register_port(0, PARPORT_IRQ_NONE,
739 						PARPORT_DMA_NONE,
740 						&parport_mos7715_ops);
741 	if (mos_parport->pp == NULL) {
742 		dev_err(&serial->interface->dev,
743 			"Could not register parport\n");
744 		kref_put(&mos_parport->ref_count, destroy_mos_parport);
745 		return -EIO;
746 	}
747 	mos_parport->pp->private_data = mos_parport;
748 	mos_parport->pp->modes = PARPORT_MODE_COMPAT | PARPORT_MODE_PCSPP;
749 	mos_parport->pp->dev = &serial->interface->dev;
750 	parport_announce_port(mos_parport->pp);
751 
752 	return 0;
753 }
754 #endif	/* CONFIG_USB_SERIAL_MOS7715_PARPORT */
755 
756 /*
757  * mos7720_interrupt_callback
758  *	this is the callback function for when we have received data on the
759  *	interrupt endpoint.
760  */
761 static void mos7720_interrupt_callback(struct urb *urb)
762 {
763 	int result;
764 	int length;
765 	int status = urb->status;
766 	struct device *dev = &urb->dev->dev;
767 	__u8 *data;
768 	__u8 sp1;
769 	__u8 sp2;
770 
771 	switch (status) {
772 	case 0:
773 		/* success */
774 		break;
775 	case -ECONNRESET:
776 	case -ENOENT:
777 	case -ESHUTDOWN:
778 		/* this urb is terminated, clean up */
779 		dev_dbg(dev, "%s - urb shutting down with status: %d\n", __func__, status);
780 		return;
781 	default:
782 		dev_dbg(dev, "%s - nonzero urb status received: %d\n", __func__, status);
783 		goto exit;
784 	}
785 
786 	length = urb->actual_length;
787 	data = urb->transfer_buffer;
788 
789 	/* Moschip get 4 bytes
790 	 * Byte 1 IIR Port 1 (port.number is 0)
791 	 * Byte 2 IIR Port 2 (port.number is 1)
792 	 * Byte 3 --------------
793 	 * Byte 4 FIFO status for both */
794 
795 	/* the above description is inverted
796 	 * 	oneukum 2007-03-14 */
797 
798 	if (unlikely(length != 4)) {
799 		dev_dbg(dev, "Wrong data !!!\n");
800 		return;
801 	}
802 
803 	sp1 = data[3];
804 	sp2 = data[2];
805 
806 	if ((sp1 | sp2) & 0x01) {
807 		/* No Interrupt Pending in both the ports */
808 		dev_dbg(dev, "No Interrupt !!!\n");
809 	} else {
810 		switch (sp1 & 0x0f) {
811 		case SERIAL_IIR_RLS:
812 			dev_dbg(dev, "Serial Port 1: Receiver status error or address bit detected in 9-bit mode\n");
813 			break;
814 		case SERIAL_IIR_CTI:
815 			dev_dbg(dev, "Serial Port 1: Receiver time out\n");
816 			break;
817 		case SERIAL_IIR_MS:
818 			/* dev_dbg(dev, "Serial Port 1: Modem status change\n"); */
819 			break;
820 		}
821 
822 		switch (sp2 & 0x0f) {
823 		case SERIAL_IIR_RLS:
824 			dev_dbg(dev, "Serial Port 2: Receiver status error or address bit detected in 9-bit mode\n");
825 			break;
826 		case SERIAL_IIR_CTI:
827 			dev_dbg(dev, "Serial Port 2: Receiver time out\n");
828 			break;
829 		case SERIAL_IIR_MS:
830 			/* dev_dbg(dev, "Serial Port 2: Modem status change\n"); */
831 			break;
832 		}
833 	}
834 
835 exit:
836 	result = usb_submit_urb(urb, GFP_ATOMIC);
837 	if (result)
838 		dev_err(dev, "%s - Error %d submitting control urb\n", __func__, result);
839 }
840 
841 /*
842  * mos7715_interrupt_callback
843  *	this is the 7715's callback function for when we have received data on
844  *	the interrupt endpoint.
845  */
846 static void mos7715_interrupt_callback(struct urb *urb)
847 {
848 	int result;
849 	int length;
850 	int status = urb->status;
851 	struct device *dev = &urb->dev->dev;
852 	__u8 *data;
853 	__u8 iir;
854 
855 	switch (status) {
856 	case 0:
857 		/* success */
858 		break;
859 	case -ECONNRESET:
860 	case -ENOENT:
861 	case -ESHUTDOWN:
862 	case -ENODEV:
863 		/* this urb is terminated, clean up */
864 		dev_dbg(dev, "%s - urb shutting down with status: %d\n", __func__, status);
865 		return;
866 	default:
867 		dev_dbg(dev, "%s - nonzero urb status received: %d\n", __func__, status);
868 		goto exit;
869 	}
870 
871 	length = urb->actual_length;
872 	data = urb->transfer_buffer;
873 
874 	/* Structure of data from 7715 device:
875 	 * Byte 1: IIR serial Port
876 	 * Byte 2: unused
877 	 * Byte 2: DSR parallel port
878 	 * Byte 4: FIFO status for both */
879 
880 	if (unlikely(length != 4)) {
881 		dev_dbg(dev, "Wrong data !!!\n");
882 		return;
883 	}
884 
885 	iir = data[0];
886 	if (!(iir & 0x01)) {	/* serial port interrupt pending */
887 		switch (iir & 0x0f) {
888 		case SERIAL_IIR_RLS:
889 			dev_dbg(dev, "Serial Port: Receiver status error or address bit detected in 9-bit mode\n");
890 			break;
891 		case SERIAL_IIR_CTI:
892 			dev_dbg(dev, "Serial Port: Receiver time out\n");
893 			break;
894 		case SERIAL_IIR_MS:
895 			/* dev_dbg(dev, "Serial Port: Modem status change\n"); */
896 			break;
897 		}
898 	}
899 
900 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
901 	{       /* update local copy of DSR reg */
902 		struct usb_serial_port *port = urb->context;
903 		struct mos7715_parport *mos_parport = port->serial->private;
904 		if (unlikely(mos_parport == NULL))
905 			return;
906 		atomic_set(&mos_parport->shadowDSR, data[2]);
907 	}
908 #endif
909 
910 exit:
911 	result = usb_submit_urb(urb, GFP_ATOMIC);
912 	if (result)
913 		dev_err(dev, "%s - Error %d submitting control urb\n", __func__, result);
914 }
915 
916 /*
917  * mos7720_bulk_in_callback
918  *	this is the callback function for when we have received data on the
919  *	bulk in endpoint.
920  */
921 static void mos7720_bulk_in_callback(struct urb *urb)
922 {
923 	int retval;
924 	unsigned char *data ;
925 	struct usb_serial_port *port;
926 	int status = urb->status;
927 
928 	if (status) {
929 		dev_dbg(&urb->dev->dev, "nonzero read bulk status received: %d\n", status);
930 		return;
931 	}
932 
933 	port = urb->context;
934 
935 	dev_dbg(&port->dev, "Entering...%s\n", __func__);
936 
937 	data = urb->transfer_buffer;
938 
939 	if (urb->actual_length) {
940 		tty_insert_flip_string(&port->port, data, urb->actual_length);
941 		tty_flip_buffer_push(&port->port);
942 	}
943 
944 	if (port->read_urb->status != -EINPROGRESS) {
945 		retval = usb_submit_urb(port->read_urb, GFP_ATOMIC);
946 		if (retval)
947 			dev_dbg(&port->dev, "usb_submit_urb(read bulk) failed, retval = %d\n", retval);
948 	}
949 }
950 
951 /*
952  * mos7720_bulk_out_data_callback
953  *	this is the callback function for when we have finished sending serial
954  *	data on the bulk out endpoint.
955  */
956 static void mos7720_bulk_out_data_callback(struct urb *urb)
957 {
958 	struct moschip_port *mos7720_port;
959 	int status = urb->status;
960 
961 	if (status) {
962 		dev_dbg(&urb->dev->dev, "nonzero write bulk status received:%d\n", status);
963 		return;
964 	}
965 
966 	mos7720_port = urb->context;
967 	if (!mos7720_port) {
968 		dev_dbg(&urb->dev->dev, "NULL mos7720_port pointer\n");
969 		return ;
970 	}
971 
972 	if (mos7720_port->open)
973 		tty_port_tty_wakeup(&mos7720_port->port->port);
974 }
975 
976 static int mos77xx_calc_num_ports(struct usb_serial *serial,
977 					struct usb_serial_endpoints *epds)
978 {
979 	u16 product = le16_to_cpu(serial->dev->descriptor.idProduct);
980 
981 	if (product == MOSCHIP_DEVICE_ID_7715) {
982 		/*
983 		 * The 7715 uses the first bulk in/out endpoint pair for the
984 		 * parallel port, and the second for the serial port. We swap
985 		 * the endpoint descriptors here so that the the first and
986 		 * only registered port structure uses the serial-port
987 		 * endpoints.
988 		 */
989 		swap(epds->bulk_in[0], epds->bulk_in[1]);
990 		swap(epds->bulk_out[0], epds->bulk_out[1]);
991 
992 		return 1;
993 	}
994 
995 	return 2;
996 }
997 
998 static int mos7720_open(struct tty_struct *tty, struct usb_serial_port *port)
999 {
1000 	struct usb_serial *serial;
1001 	struct urb *urb;
1002 	struct moschip_port *mos7720_port;
1003 	int response;
1004 	int port_number;
1005 	__u8 data;
1006 	int allocated_urbs = 0;
1007 	int j;
1008 
1009 	serial = port->serial;
1010 
1011 	mos7720_port = usb_get_serial_port_data(port);
1012 	if (mos7720_port == NULL)
1013 		return -ENODEV;
1014 
1015 	usb_clear_halt(serial->dev, port->write_urb->pipe);
1016 	usb_clear_halt(serial->dev, port->read_urb->pipe);
1017 
1018 	/* Initialising the write urb pool */
1019 	for (j = 0; j < NUM_URBS; ++j) {
1020 		urb = usb_alloc_urb(0, GFP_KERNEL);
1021 		mos7720_port->write_urb_pool[j] = urb;
1022 		if (!urb)
1023 			continue;
1024 
1025 		urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE,
1026 					       GFP_KERNEL);
1027 		if (!urb->transfer_buffer) {
1028 			usb_free_urb(mos7720_port->write_urb_pool[j]);
1029 			mos7720_port->write_urb_pool[j] = NULL;
1030 			continue;
1031 		}
1032 		allocated_urbs++;
1033 	}
1034 
1035 	if (!allocated_urbs)
1036 		return -ENOMEM;
1037 
1038 	 /* Initialize MCS7720 -- Write Init values to corresponding Registers
1039 	  *
1040 	  * Register Index
1041 	  * 0 : MOS7720_THR/MOS7720_RHR
1042 	  * 1 : MOS7720_IER
1043 	  * 2 : MOS7720_FCR
1044 	  * 3 : MOS7720_LCR
1045 	  * 4 : MOS7720_MCR
1046 	  * 5 : MOS7720_LSR
1047 	  * 6 : MOS7720_MSR
1048 	  * 7 : MOS7720_SPR
1049 	  *
1050 	  * 0x08 : SP1/2 Control Reg
1051 	  */
1052 	port_number = port->port_number;
1053 	read_mos_reg(serial, port_number, MOS7720_LSR, &data);
1054 
1055 	dev_dbg(&port->dev, "SS::%p LSR:%x\n", mos7720_port, data);
1056 
1057 	write_mos_reg(serial, dummy, MOS7720_SP1_REG, 0x02);
1058 	write_mos_reg(serial, dummy, MOS7720_SP2_REG, 0x02);
1059 
1060 	write_mos_reg(serial, port_number, MOS7720_IER, 0x00);
1061 	write_mos_reg(serial, port_number, MOS7720_FCR, 0x00);
1062 
1063 	write_mos_reg(serial, port_number, MOS7720_FCR, 0xcf);
1064 	mos7720_port->shadowLCR = 0x03;
1065 	write_mos_reg(serial, port_number, MOS7720_LCR,
1066 		      mos7720_port->shadowLCR);
1067 	mos7720_port->shadowMCR = 0x0b;
1068 	write_mos_reg(serial, port_number, MOS7720_MCR,
1069 		      mos7720_port->shadowMCR);
1070 
1071 	write_mos_reg(serial, port_number, MOS7720_SP_CONTROL_REG, 0x00);
1072 	read_mos_reg(serial, dummy, MOS7720_SP_CONTROL_REG, &data);
1073 	data = data | (port->port_number + 1);
1074 	write_mos_reg(serial, dummy, MOS7720_SP_CONTROL_REG, data);
1075 	mos7720_port->shadowLCR = 0x83;
1076 	write_mos_reg(serial, port_number, MOS7720_LCR,
1077 		      mos7720_port->shadowLCR);
1078 	write_mos_reg(serial, port_number, MOS7720_THR, 0x0c);
1079 	write_mos_reg(serial, port_number, MOS7720_IER, 0x00);
1080 	mos7720_port->shadowLCR = 0x03;
1081 	write_mos_reg(serial, port_number, MOS7720_LCR,
1082 		      mos7720_port->shadowLCR);
1083 	write_mos_reg(serial, port_number, MOS7720_IER, 0x0c);
1084 
1085 	response = usb_submit_urb(port->read_urb, GFP_KERNEL);
1086 	if (response)
1087 		dev_err(&port->dev, "%s - Error %d submitting read urb\n",
1088 							__func__, response);
1089 
1090 	/* initialize our port settings */
1091 	mos7720_port->shadowMCR = UART_MCR_OUT2; /* Must set to enable ints! */
1092 
1093 	/* send a open port command */
1094 	mos7720_port->open = 1;
1095 
1096 	return 0;
1097 }
1098 
1099 /*
1100  * mos7720_chars_in_buffer
1101  *	this function is called by the tty driver when it wants to know how many
1102  *	bytes of data we currently have outstanding in the port (data that has
1103  *	been written, but hasn't made it out the port yet)
1104  *	If successful, we return the number of bytes left to be written in the
1105  *	system,
1106  *	Otherwise we return a negative error number.
1107  */
1108 static int mos7720_chars_in_buffer(struct tty_struct *tty)
1109 {
1110 	struct usb_serial_port *port = tty->driver_data;
1111 	int i;
1112 	int chars = 0;
1113 	struct moschip_port *mos7720_port;
1114 
1115 	mos7720_port = usb_get_serial_port_data(port);
1116 	if (mos7720_port == NULL)
1117 		return 0;
1118 
1119 	for (i = 0; i < NUM_URBS; ++i) {
1120 		if (mos7720_port->write_urb_pool[i] &&
1121 		    mos7720_port->write_urb_pool[i]->status == -EINPROGRESS)
1122 			chars += URB_TRANSFER_BUFFER_SIZE;
1123 	}
1124 	dev_dbg(&port->dev, "%s - returns %d\n", __func__, chars);
1125 	return chars;
1126 }
1127 
1128 static void mos7720_close(struct usb_serial_port *port)
1129 {
1130 	struct usb_serial *serial;
1131 	struct moschip_port *mos7720_port;
1132 	int j;
1133 
1134 	serial = port->serial;
1135 
1136 	mos7720_port = usb_get_serial_port_data(port);
1137 	if (mos7720_port == NULL)
1138 		return;
1139 
1140 	for (j = 0; j < NUM_URBS; ++j)
1141 		usb_kill_urb(mos7720_port->write_urb_pool[j]);
1142 
1143 	/* Freeing Write URBs */
1144 	for (j = 0; j < NUM_URBS; ++j) {
1145 		if (mos7720_port->write_urb_pool[j]) {
1146 			kfree(mos7720_port->write_urb_pool[j]->transfer_buffer);
1147 			usb_free_urb(mos7720_port->write_urb_pool[j]);
1148 		}
1149 	}
1150 
1151 	/* While closing port, shutdown all bulk read, write  *
1152 	 * and interrupt read if they exists, otherwise nop   */
1153 	usb_kill_urb(port->write_urb);
1154 	usb_kill_urb(port->read_urb);
1155 
1156 	write_mos_reg(serial, port->port_number, MOS7720_MCR, 0x00);
1157 	write_mos_reg(serial, port->port_number, MOS7720_IER, 0x00);
1158 
1159 	mos7720_port->open = 0;
1160 }
1161 
1162 static void mos7720_break(struct tty_struct *tty, int break_state)
1163 {
1164 	struct usb_serial_port *port = tty->driver_data;
1165 	unsigned char data;
1166 	struct usb_serial *serial;
1167 	struct moschip_port *mos7720_port;
1168 
1169 	serial = port->serial;
1170 
1171 	mos7720_port = usb_get_serial_port_data(port);
1172 	if (mos7720_port == NULL)
1173 		return;
1174 
1175 	if (break_state == -1)
1176 		data = mos7720_port->shadowLCR | UART_LCR_SBC;
1177 	else
1178 		data = mos7720_port->shadowLCR & ~UART_LCR_SBC;
1179 
1180 	mos7720_port->shadowLCR  = data;
1181 	write_mos_reg(serial, port->port_number, MOS7720_LCR,
1182 		      mos7720_port->shadowLCR);
1183 }
1184 
1185 /*
1186  * mos7720_write_room
1187  *	this function is called by the tty driver when it wants to know how many
1188  *	bytes of data we can accept for a specific port.
1189  *	If successful, we return the amount of room that we have for this port
1190  *	Otherwise we return a negative error number.
1191  */
1192 static int mos7720_write_room(struct tty_struct *tty)
1193 {
1194 	struct usb_serial_port *port = tty->driver_data;
1195 	struct moschip_port *mos7720_port;
1196 	int room = 0;
1197 	int i;
1198 
1199 	mos7720_port = usb_get_serial_port_data(port);
1200 	if (mos7720_port == NULL)
1201 		return -ENODEV;
1202 
1203 	/* FIXME: Locking */
1204 	for (i = 0; i < NUM_URBS; ++i) {
1205 		if (mos7720_port->write_urb_pool[i] &&
1206 		    mos7720_port->write_urb_pool[i]->status != -EINPROGRESS)
1207 			room += URB_TRANSFER_BUFFER_SIZE;
1208 	}
1209 
1210 	dev_dbg(&port->dev, "%s - returns %d\n", __func__, room);
1211 	return room;
1212 }
1213 
1214 static int mos7720_write(struct tty_struct *tty, struct usb_serial_port *port,
1215 				 const unsigned char *data, int count)
1216 {
1217 	int status;
1218 	int i;
1219 	int bytes_sent = 0;
1220 	int transfer_size;
1221 
1222 	struct moschip_port *mos7720_port;
1223 	struct usb_serial *serial;
1224 	struct urb    *urb;
1225 	const unsigned char *current_position = data;
1226 
1227 	serial = port->serial;
1228 
1229 	mos7720_port = usb_get_serial_port_data(port);
1230 	if (mos7720_port == NULL)
1231 		return -ENODEV;
1232 
1233 	/* try to find a free urb in the list */
1234 	urb = NULL;
1235 
1236 	for (i = 0; i < NUM_URBS; ++i) {
1237 		if (mos7720_port->write_urb_pool[i] &&
1238 		    mos7720_port->write_urb_pool[i]->status != -EINPROGRESS) {
1239 			urb = mos7720_port->write_urb_pool[i];
1240 			dev_dbg(&port->dev, "URB:%d\n", i);
1241 			break;
1242 		}
1243 	}
1244 
1245 	if (urb == NULL) {
1246 		dev_dbg(&port->dev, "%s - no more free urbs\n", __func__);
1247 		goto exit;
1248 	}
1249 
1250 	if (urb->transfer_buffer == NULL) {
1251 		urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE,
1252 					       GFP_ATOMIC);
1253 		if (!urb->transfer_buffer)
1254 			goto exit;
1255 	}
1256 	transfer_size = min(count, URB_TRANSFER_BUFFER_SIZE);
1257 
1258 	memcpy(urb->transfer_buffer, current_position, transfer_size);
1259 	usb_serial_debug_data(&port->dev, __func__, transfer_size,
1260 			      urb->transfer_buffer);
1261 
1262 	/* fill urb with data and submit  */
1263 	usb_fill_bulk_urb(urb, serial->dev,
1264 			  usb_sndbulkpipe(serial->dev,
1265 					port->bulk_out_endpointAddress),
1266 			  urb->transfer_buffer, transfer_size,
1267 			  mos7720_bulk_out_data_callback, mos7720_port);
1268 
1269 	/* send it down the pipe */
1270 	status = usb_submit_urb(urb, GFP_ATOMIC);
1271 	if (status) {
1272 		dev_err_console(port, "%s - usb_submit_urb(write bulk) failed "
1273 			"with status = %d\n", __func__, status);
1274 		bytes_sent = status;
1275 		goto exit;
1276 	}
1277 	bytes_sent = transfer_size;
1278 
1279 exit:
1280 	return bytes_sent;
1281 }
1282 
1283 static void mos7720_throttle(struct tty_struct *tty)
1284 {
1285 	struct usb_serial_port *port = tty->driver_data;
1286 	struct moschip_port *mos7720_port;
1287 	int status;
1288 
1289 	mos7720_port = usb_get_serial_port_data(port);
1290 
1291 	if (mos7720_port == NULL)
1292 		return;
1293 
1294 	if (!mos7720_port->open) {
1295 		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
1296 		return;
1297 	}
1298 
1299 	/* if we are implementing XON/XOFF, send the stop character */
1300 	if (I_IXOFF(tty)) {
1301 		unsigned char stop_char = STOP_CHAR(tty);
1302 		status = mos7720_write(tty, port, &stop_char, 1);
1303 		if (status <= 0)
1304 			return;
1305 	}
1306 
1307 	/* if we are implementing RTS/CTS, toggle that line */
1308 	if (C_CRTSCTS(tty)) {
1309 		mos7720_port->shadowMCR &= ~UART_MCR_RTS;
1310 		write_mos_reg(port->serial, port->port_number, MOS7720_MCR,
1311 			      mos7720_port->shadowMCR);
1312 	}
1313 }
1314 
1315 static void mos7720_unthrottle(struct tty_struct *tty)
1316 {
1317 	struct usb_serial_port *port = tty->driver_data;
1318 	struct moschip_port *mos7720_port = usb_get_serial_port_data(port);
1319 	int status;
1320 
1321 	if (mos7720_port == NULL)
1322 		return;
1323 
1324 	if (!mos7720_port->open) {
1325 		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
1326 		return;
1327 	}
1328 
1329 	/* if we are implementing XON/XOFF, send the start character */
1330 	if (I_IXOFF(tty)) {
1331 		unsigned char start_char = START_CHAR(tty);
1332 		status = mos7720_write(tty, port, &start_char, 1);
1333 		if (status <= 0)
1334 			return;
1335 	}
1336 
1337 	/* if we are implementing RTS/CTS, toggle that line */
1338 	if (C_CRTSCTS(tty)) {
1339 		mos7720_port->shadowMCR |= UART_MCR_RTS;
1340 		write_mos_reg(port->serial, port->port_number, MOS7720_MCR,
1341 			      mos7720_port->shadowMCR);
1342 	}
1343 }
1344 
1345 /* FIXME: this function does not work */
1346 static int set_higher_rates(struct moschip_port *mos7720_port,
1347 			    unsigned int baud)
1348 {
1349 	struct usb_serial_port *port;
1350 	struct usb_serial *serial;
1351 	int port_number;
1352 	enum mos_regs sp_reg;
1353 	if (mos7720_port == NULL)
1354 		return -EINVAL;
1355 
1356 	port = mos7720_port->port;
1357 	serial = port->serial;
1358 
1359 	 /***********************************************
1360 	 *      Init Sequence for higher rates
1361 	 ***********************************************/
1362 	dev_dbg(&port->dev, "Sending Setting Commands ..........\n");
1363 	port_number = port->port_number;
1364 
1365 	write_mos_reg(serial, port_number, MOS7720_IER, 0x00);
1366 	write_mos_reg(serial, port_number, MOS7720_FCR, 0x00);
1367 	write_mos_reg(serial, port_number, MOS7720_FCR, 0xcf);
1368 	mos7720_port->shadowMCR = 0x0b;
1369 	write_mos_reg(serial, port_number, MOS7720_MCR,
1370 		      mos7720_port->shadowMCR);
1371 	write_mos_reg(serial, dummy, MOS7720_SP_CONTROL_REG, 0x00);
1372 
1373 	/***********************************************
1374 	 *              Set for higher rates           *
1375 	 ***********************************************/
1376 	/* writing baud rate verbatum into uart clock field clearly not right */
1377 	if (port_number == 0)
1378 		sp_reg = MOS7720_SP1_REG;
1379 	else
1380 		sp_reg = MOS7720_SP2_REG;
1381 	write_mos_reg(serial, dummy, sp_reg, baud * 0x10);
1382 	write_mos_reg(serial, dummy, MOS7720_SP_CONTROL_REG, 0x03);
1383 	mos7720_port->shadowMCR = 0x2b;
1384 	write_mos_reg(serial, port_number, MOS7720_MCR,
1385 		      mos7720_port->shadowMCR);
1386 
1387 	/***********************************************
1388 	 *              Set DLL/DLM
1389 	 ***********************************************/
1390 	mos7720_port->shadowLCR = mos7720_port->shadowLCR | UART_LCR_DLAB;
1391 	write_mos_reg(serial, port_number, MOS7720_LCR,
1392 		      mos7720_port->shadowLCR);
1393 	write_mos_reg(serial, port_number, MOS7720_DLL, 0x01);
1394 	write_mos_reg(serial, port_number, MOS7720_DLM, 0x00);
1395 	mos7720_port->shadowLCR = mos7720_port->shadowLCR & ~UART_LCR_DLAB;
1396 	write_mos_reg(serial, port_number, MOS7720_LCR,
1397 		      mos7720_port->shadowLCR);
1398 
1399 	return 0;
1400 }
1401 
1402 /* baud rate information */
1403 struct divisor_table_entry {
1404 	__u32  baudrate;
1405 	__u16  divisor;
1406 };
1407 
1408 /* Define table of divisors for moschip 7720 hardware	   *
1409  * These assume a 3.6864MHz crystal, the standard /16, and *
1410  * MCR.7 = 0.						   */
1411 static const struct divisor_table_entry divisor_table[] = {
1412 	{   50,		2304},
1413 	{   110,	1047},	/* 2094.545455 => 230450   => .0217 % over */
1414 	{   134,	857},	/* 1713.011152 => 230398.5 => .00065% under */
1415 	{   150,	768},
1416 	{   300,	384},
1417 	{   600,	192},
1418 	{   1200,	96},
1419 	{   1800,	64},
1420 	{   2400,	48},
1421 	{   4800,	24},
1422 	{   7200,	16},
1423 	{   9600,	12},
1424 	{   19200,	6},
1425 	{   38400,	3},
1426 	{   57600,	2},
1427 	{   115200,	1},
1428 };
1429 
1430 /*****************************************************************************
1431  * calc_baud_rate_divisor
1432  *	this function calculates the proper baud rate divisor for the specified
1433  *	baud rate.
1434  *****************************************************************************/
1435 static int calc_baud_rate_divisor(struct usb_serial_port *port, int baudrate, int *divisor)
1436 {
1437 	int i;
1438 	__u16 custom;
1439 	__u16 round1;
1440 	__u16 round;
1441 
1442 
1443 	dev_dbg(&port->dev, "%s - %d\n", __func__, baudrate);
1444 
1445 	for (i = 0; i < ARRAY_SIZE(divisor_table); i++) {
1446 		if (divisor_table[i].baudrate == baudrate) {
1447 			*divisor = divisor_table[i].divisor;
1448 			return 0;
1449 		}
1450 	}
1451 
1452 	/* After trying for all the standard baud rates    *
1453 	 * Try calculating the divisor for this baud rate  */
1454 	if (baudrate > 75 &&  baudrate < 230400) {
1455 		/* get the divisor */
1456 		custom = (__u16)(230400L  / baudrate);
1457 
1458 		/* Check for round off */
1459 		round1 = (__u16)(2304000L / baudrate);
1460 		round = (__u16)(round1 - (custom * 10));
1461 		if (round > 4)
1462 			custom++;
1463 		*divisor = custom;
1464 
1465 		dev_dbg(&port->dev, "Baud %d = %d\n", baudrate, custom);
1466 		return 0;
1467 	}
1468 
1469 	dev_dbg(&port->dev, "Baud calculation Failed...\n");
1470 	return -EINVAL;
1471 }
1472 
1473 /*
1474  * send_cmd_write_baud_rate
1475  *	this function sends the proper command to change the baud rate of the
1476  *	specified port.
1477  */
1478 static int send_cmd_write_baud_rate(struct moschip_port *mos7720_port,
1479 				    int baudrate)
1480 {
1481 	struct usb_serial_port *port;
1482 	struct usb_serial *serial;
1483 	int divisor;
1484 	int status;
1485 	unsigned char number;
1486 
1487 	if (mos7720_port == NULL)
1488 		return -1;
1489 
1490 	port = mos7720_port->port;
1491 	serial = port->serial;
1492 
1493 	number = port->port_number;
1494 	dev_dbg(&port->dev, "%s - baud = %d\n", __func__, baudrate);
1495 
1496 	/* Calculate the Divisor */
1497 	status = calc_baud_rate_divisor(port, baudrate, &divisor);
1498 	if (status) {
1499 		dev_err(&port->dev, "%s - bad baud rate\n", __func__);
1500 		return status;
1501 	}
1502 
1503 	/* Enable access to divisor latch */
1504 	mos7720_port->shadowLCR = mos7720_port->shadowLCR | UART_LCR_DLAB;
1505 	write_mos_reg(serial, number, MOS7720_LCR, mos7720_port->shadowLCR);
1506 
1507 	/* Write the divisor */
1508 	write_mos_reg(serial, number, MOS7720_DLL, (__u8)(divisor & 0xff));
1509 	write_mos_reg(serial, number, MOS7720_DLM,
1510 		      (__u8)((divisor & 0xff00) >> 8));
1511 
1512 	/* Disable access to divisor latch */
1513 	mos7720_port->shadowLCR = mos7720_port->shadowLCR & ~UART_LCR_DLAB;
1514 	write_mos_reg(serial, number, MOS7720_LCR, mos7720_port->shadowLCR);
1515 
1516 	return status;
1517 }
1518 
1519 /*
1520  * change_port_settings
1521  *	This routine is called to set the UART on the device to match
1522  *      the specified new settings.
1523  */
1524 static void change_port_settings(struct tty_struct *tty,
1525 				 struct moschip_port *mos7720_port,
1526 				 struct ktermios *old_termios)
1527 {
1528 	struct usb_serial_port *port;
1529 	struct usb_serial *serial;
1530 	int baud;
1531 	unsigned cflag;
1532 	unsigned iflag;
1533 	__u8 mask = 0xff;
1534 	__u8 lData;
1535 	__u8 lParity;
1536 	__u8 lStop;
1537 	int status;
1538 	int port_number;
1539 
1540 	if (mos7720_port == NULL)
1541 		return ;
1542 
1543 	port = mos7720_port->port;
1544 	serial = port->serial;
1545 	port_number = port->port_number;
1546 
1547 	if (!mos7720_port->open) {
1548 		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
1549 		return;
1550 	}
1551 
1552 	lData = UART_LCR_WLEN8;
1553 	lStop = 0x00;	/* 1 stop bit */
1554 	lParity = 0x00;	/* No parity */
1555 
1556 	cflag = tty->termios.c_cflag;
1557 	iflag = tty->termios.c_iflag;
1558 
1559 	/* Change the number of bits */
1560 	switch (cflag & CSIZE) {
1561 	case CS5:
1562 		lData = UART_LCR_WLEN5;
1563 		mask = 0x1f;
1564 		break;
1565 
1566 	case CS6:
1567 		lData = UART_LCR_WLEN6;
1568 		mask = 0x3f;
1569 		break;
1570 
1571 	case CS7:
1572 		lData = UART_LCR_WLEN7;
1573 		mask = 0x7f;
1574 		break;
1575 	default:
1576 	case CS8:
1577 		lData = UART_LCR_WLEN8;
1578 		break;
1579 	}
1580 
1581 	/* Change the Parity bit */
1582 	if (cflag & PARENB) {
1583 		if (cflag & PARODD) {
1584 			lParity = UART_LCR_PARITY;
1585 			dev_dbg(&port->dev, "%s - parity = odd\n", __func__);
1586 		} else {
1587 			lParity = (UART_LCR_EPAR | UART_LCR_PARITY);
1588 			dev_dbg(&port->dev, "%s - parity = even\n", __func__);
1589 		}
1590 
1591 	} else {
1592 		dev_dbg(&port->dev, "%s - parity = none\n", __func__);
1593 	}
1594 
1595 	if (cflag & CMSPAR)
1596 		lParity = lParity | 0x20;
1597 
1598 	/* Change the Stop bit */
1599 	if (cflag & CSTOPB) {
1600 		lStop = UART_LCR_STOP;
1601 		dev_dbg(&port->dev, "%s - stop bits = 2\n", __func__);
1602 	} else {
1603 		lStop = 0x00;
1604 		dev_dbg(&port->dev, "%s - stop bits = 1\n", __func__);
1605 	}
1606 
1607 #define LCR_BITS_MASK		0x03	/* Mask for bits/char field */
1608 #define LCR_STOP_MASK		0x04	/* Mask for stop bits field */
1609 #define LCR_PAR_MASK		0x38	/* Mask for parity field */
1610 
1611 	/* Update the LCR with the correct value */
1612 	mos7720_port->shadowLCR &=
1613 		~(LCR_BITS_MASK | LCR_STOP_MASK | LCR_PAR_MASK);
1614 	mos7720_port->shadowLCR |= (lData | lParity | lStop);
1615 
1616 
1617 	/* Disable Interrupts */
1618 	write_mos_reg(serial, port_number, MOS7720_IER, 0x00);
1619 	write_mos_reg(serial, port_number, MOS7720_FCR, 0x00);
1620 	write_mos_reg(serial, port_number, MOS7720_FCR, 0xcf);
1621 
1622 	/* Send the updated LCR value to the mos7720 */
1623 	write_mos_reg(serial, port_number, MOS7720_LCR,
1624 		      mos7720_port->shadowLCR);
1625 	mos7720_port->shadowMCR = 0x0b;
1626 	write_mos_reg(serial, port_number, MOS7720_MCR,
1627 		      mos7720_port->shadowMCR);
1628 
1629 	/* set up the MCR register and send it to the mos7720 */
1630 	mos7720_port->shadowMCR = UART_MCR_OUT2;
1631 	if (cflag & CBAUD)
1632 		mos7720_port->shadowMCR |= (UART_MCR_DTR | UART_MCR_RTS);
1633 
1634 	if (cflag & CRTSCTS) {
1635 		mos7720_port->shadowMCR |= (UART_MCR_XONANY);
1636 		/* To set hardware flow control to the specified *
1637 		 * serial port, in SP1/2_CONTROL_REG             */
1638 		if (port_number)
1639 			write_mos_reg(serial, dummy, MOS7720_SP_CONTROL_REG,
1640 				      0x01);
1641 		else
1642 			write_mos_reg(serial, dummy, MOS7720_SP_CONTROL_REG,
1643 				      0x02);
1644 
1645 	} else
1646 		mos7720_port->shadowMCR &= ~(UART_MCR_XONANY);
1647 
1648 	write_mos_reg(serial, port_number, MOS7720_MCR,
1649 		      mos7720_port->shadowMCR);
1650 
1651 	/* Determine divisor based on baud rate */
1652 	baud = tty_get_baud_rate(tty);
1653 	if (!baud) {
1654 		/* pick a default, any default... */
1655 		dev_dbg(&port->dev, "Picked default baud...\n");
1656 		baud = 9600;
1657 	}
1658 
1659 	if (baud >= 230400) {
1660 		set_higher_rates(mos7720_port, baud);
1661 		/* Enable Interrupts */
1662 		write_mos_reg(serial, port_number, MOS7720_IER, 0x0c);
1663 		return;
1664 	}
1665 
1666 	dev_dbg(&port->dev, "%s - baud rate = %d\n", __func__, baud);
1667 	status = send_cmd_write_baud_rate(mos7720_port, baud);
1668 	/* FIXME: needs to write actual resulting baud back not just
1669 	   blindly do so */
1670 	if (cflag & CBAUD)
1671 		tty_encode_baud_rate(tty, baud, baud);
1672 	/* Enable Interrupts */
1673 	write_mos_reg(serial, port_number, MOS7720_IER, 0x0c);
1674 
1675 	if (port->read_urb->status != -EINPROGRESS) {
1676 		status = usb_submit_urb(port->read_urb, GFP_KERNEL);
1677 		if (status)
1678 			dev_dbg(&port->dev, "usb_submit_urb(read bulk) failed, status = %d\n", status);
1679 	}
1680 }
1681 
1682 /*
1683  * mos7720_set_termios
1684  *	this function is called by the tty driver when it wants to change the
1685  *	termios structure.
1686  */
1687 static void mos7720_set_termios(struct tty_struct *tty,
1688 		struct usb_serial_port *port, struct ktermios *old_termios)
1689 {
1690 	int status;
1691 	struct usb_serial *serial;
1692 	struct moschip_port *mos7720_port;
1693 
1694 	serial = port->serial;
1695 
1696 	mos7720_port = usb_get_serial_port_data(port);
1697 
1698 	if (mos7720_port == NULL)
1699 		return;
1700 
1701 	if (!mos7720_port->open) {
1702 		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
1703 		return;
1704 	}
1705 
1706 	/* change the port settings to the new ones specified */
1707 	change_port_settings(tty, mos7720_port, old_termios);
1708 
1709 	if (port->read_urb->status != -EINPROGRESS) {
1710 		status = usb_submit_urb(port->read_urb, GFP_KERNEL);
1711 		if (status)
1712 			dev_dbg(&port->dev, "usb_submit_urb(read bulk) failed, status = %d\n", status);
1713 	}
1714 }
1715 
1716 /*
1717  * get_lsr_info - get line status register info
1718  *
1719  * Purpose: Let user call ioctl() to get info when the UART physically
1720  * 	    is emptied.  On bus types like RS485, the transmitter must
1721  * 	    release the bus after transmitting. This must be done when
1722  * 	    the transmit shift register is empty, not be done when the
1723  * 	    transmit holding register is empty.  This functionality
1724  * 	    allows an RS485 driver to be written in user space.
1725  */
1726 static int get_lsr_info(struct tty_struct *tty,
1727 		struct moschip_port *mos7720_port, unsigned int __user *value)
1728 {
1729 	struct usb_serial_port *port = tty->driver_data;
1730 	unsigned int result = 0;
1731 	unsigned char data = 0;
1732 	int port_number = port->port_number;
1733 	int count;
1734 
1735 	count = mos7720_chars_in_buffer(tty);
1736 	if (count == 0) {
1737 		read_mos_reg(port->serial, port_number, MOS7720_LSR, &data);
1738 		if ((data & (UART_LSR_TEMT | UART_LSR_THRE))
1739 					== (UART_LSR_TEMT | UART_LSR_THRE)) {
1740 			dev_dbg(&port->dev, "%s -- Empty\n", __func__);
1741 			result = TIOCSER_TEMT;
1742 		}
1743 	}
1744 	if (copy_to_user(value, &result, sizeof(int)))
1745 		return -EFAULT;
1746 	return 0;
1747 }
1748 
1749 static int mos7720_tiocmget(struct tty_struct *tty)
1750 {
1751 	struct usb_serial_port *port = tty->driver_data;
1752 	struct moschip_port *mos7720_port = usb_get_serial_port_data(port);
1753 	unsigned int result = 0;
1754 	unsigned int mcr ;
1755 	unsigned int msr ;
1756 
1757 	mcr = mos7720_port->shadowMCR;
1758 	msr = mos7720_port->shadowMSR;
1759 
1760 	result = ((mcr & UART_MCR_DTR)  ? TIOCM_DTR : 0)   /* 0x002 */
1761 	  | ((mcr & UART_MCR_RTS)   ? TIOCM_RTS : 0)   /* 0x004 */
1762 	  | ((msr & UART_MSR_CTS)   ? TIOCM_CTS : 0)   /* 0x020 */
1763 	  | ((msr & UART_MSR_DCD)   ? TIOCM_CAR : 0)   /* 0x040 */
1764 	  | ((msr & UART_MSR_RI)    ? TIOCM_RI :  0)   /* 0x080 */
1765 	  | ((msr & UART_MSR_DSR)   ? TIOCM_DSR : 0);  /* 0x100 */
1766 
1767 	return result;
1768 }
1769 
1770 static int mos7720_tiocmset(struct tty_struct *tty,
1771 			    unsigned int set, unsigned int clear)
1772 {
1773 	struct usb_serial_port *port = tty->driver_data;
1774 	struct moschip_port *mos7720_port = usb_get_serial_port_data(port);
1775 	unsigned int mcr ;
1776 
1777 	mcr = mos7720_port->shadowMCR;
1778 
1779 	if (set & TIOCM_RTS)
1780 		mcr |= UART_MCR_RTS;
1781 	if (set & TIOCM_DTR)
1782 		mcr |= UART_MCR_DTR;
1783 	if (set & TIOCM_LOOP)
1784 		mcr |= UART_MCR_LOOP;
1785 
1786 	if (clear & TIOCM_RTS)
1787 		mcr &= ~UART_MCR_RTS;
1788 	if (clear & TIOCM_DTR)
1789 		mcr &= ~UART_MCR_DTR;
1790 	if (clear & TIOCM_LOOP)
1791 		mcr &= ~UART_MCR_LOOP;
1792 
1793 	mos7720_port->shadowMCR = mcr;
1794 	write_mos_reg(port->serial, port->port_number, MOS7720_MCR,
1795 		      mos7720_port->shadowMCR);
1796 
1797 	return 0;
1798 }
1799 
1800 static int set_modem_info(struct moschip_port *mos7720_port, unsigned int cmd,
1801 			  unsigned int __user *value)
1802 {
1803 	unsigned int mcr;
1804 	unsigned int arg;
1805 
1806 	struct usb_serial_port *port;
1807 
1808 	if (mos7720_port == NULL)
1809 		return -1;
1810 
1811 	port = (struct usb_serial_port *)mos7720_port->port;
1812 	mcr = mos7720_port->shadowMCR;
1813 
1814 	if (copy_from_user(&arg, value, sizeof(int)))
1815 		return -EFAULT;
1816 
1817 	switch (cmd) {
1818 	case TIOCMBIS:
1819 		if (arg & TIOCM_RTS)
1820 			mcr |= UART_MCR_RTS;
1821 		if (arg & TIOCM_DTR)
1822 			mcr |= UART_MCR_RTS;
1823 		if (arg & TIOCM_LOOP)
1824 			mcr |= UART_MCR_LOOP;
1825 		break;
1826 
1827 	case TIOCMBIC:
1828 		if (arg & TIOCM_RTS)
1829 			mcr &= ~UART_MCR_RTS;
1830 		if (arg & TIOCM_DTR)
1831 			mcr &= ~UART_MCR_RTS;
1832 		if (arg & TIOCM_LOOP)
1833 			mcr &= ~UART_MCR_LOOP;
1834 		break;
1835 
1836 	}
1837 
1838 	mos7720_port->shadowMCR = mcr;
1839 	write_mos_reg(port->serial, port->port_number, MOS7720_MCR,
1840 		      mos7720_port->shadowMCR);
1841 
1842 	return 0;
1843 }
1844 
1845 static int get_serial_info(struct moschip_port *mos7720_port,
1846 			   struct serial_struct __user *retinfo)
1847 {
1848 	struct serial_struct tmp;
1849 
1850 	memset(&tmp, 0, sizeof(tmp));
1851 
1852 	tmp.type		= PORT_16550A;
1853 	tmp.line		= mos7720_port->port->minor;
1854 	tmp.port		= mos7720_port->port->port_number;
1855 	tmp.irq			= 0;
1856 	tmp.xmit_fifo_size	= NUM_URBS * URB_TRANSFER_BUFFER_SIZE;
1857 	tmp.baud_base		= 9600;
1858 	tmp.close_delay		= 5*HZ;
1859 	tmp.closing_wait	= 30*HZ;
1860 
1861 	if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
1862 		return -EFAULT;
1863 	return 0;
1864 }
1865 
1866 static int mos7720_ioctl(struct tty_struct *tty,
1867 			 unsigned int cmd, unsigned long arg)
1868 {
1869 	struct usb_serial_port *port = tty->driver_data;
1870 	struct moschip_port *mos7720_port;
1871 
1872 	mos7720_port = usb_get_serial_port_data(port);
1873 	if (mos7720_port == NULL)
1874 		return -ENODEV;
1875 
1876 	switch (cmd) {
1877 	case TIOCSERGETLSR:
1878 		dev_dbg(&port->dev, "%s TIOCSERGETLSR\n", __func__);
1879 		return get_lsr_info(tty, mos7720_port,
1880 					(unsigned int __user *)arg);
1881 
1882 	/* FIXME: These should be using the mode methods */
1883 	case TIOCMBIS:
1884 	case TIOCMBIC:
1885 		dev_dbg(&port->dev, "%s TIOCMSET/TIOCMBIC/TIOCMSET\n", __func__);
1886 		return set_modem_info(mos7720_port, cmd,
1887 				      (unsigned int __user *)arg);
1888 
1889 	case TIOCGSERIAL:
1890 		dev_dbg(&port->dev, "%s TIOCGSERIAL\n", __func__);
1891 		return get_serial_info(mos7720_port,
1892 				       (struct serial_struct __user *)arg);
1893 	}
1894 
1895 	return -ENOIOCTLCMD;
1896 }
1897 
1898 static int mos7720_startup(struct usb_serial *serial)
1899 {
1900 	struct usb_device *dev;
1901 	char data;
1902 	u16 product;
1903 	int ret_val;
1904 
1905 	product = le16_to_cpu(serial->dev->descriptor.idProduct);
1906 	dev = serial->dev;
1907 
1908 	/* setting configuration feature to one */
1909 	usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
1910 			(__u8)0x03, 0x00, 0x01, 0x00, NULL, 0x00, 5000);
1911 
1912 	if (product == MOSCHIP_DEVICE_ID_7715) {
1913 		struct urb *urb = serial->port[0]->interrupt_in_urb;
1914 
1915 		urb->complete = mos7715_interrupt_callback;
1916 
1917 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
1918 		ret_val = mos7715_parport_init(serial);
1919 		if (ret_val < 0)
1920 			return ret_val;
1921 #endif
1922 	}
1923 	/* start the interrupt urb */
1924 	ret_val = usb_submit_urb(serial->port[0]->interrupt_in_urb, GFP_KERNEL);
1925 	if (ret_val) {
1926 		dev_err(&dev->dev, "failed to submit interrupt urb: %d\n",
1927 			ret_val);
1928 	}
1929 
1930 	/* LSR For Port 1 */
1931 	read_mos_reg(serial, 0, MOS7720_LSR, &data);
1932 	dev_dbg(&dev->dev, "LSR:%x\n", data);
1933 
1934 	return 0;
1935 }
1936 
1937 static void mos7720_release(struct usb_serial *serial)
1938 {
1939 	usb_kill_urb(serial->port[0]->interrupt_in_urb);
1940 
1941 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
1942 	/* close the parallel port */
1943 
1944 	if (le16_to_cpu(serial->dev->descriptor.idProduct)
1945 	    == MOSCHIP_DEVICE_ID_7715) {
1946 		struct urbtracker *urbtrack;
1947 		unsigned long flags;
1948 		struct mos7715_parport *mos_parport =
1949 			usb_get_serial_data(serial);
1950 
1951 		/* prevent NULL ptr dereference in port callbacks */
1952 		spin_lock(&release_lock);
1953 		mos_parport->pp->private_data = NULL;
1954 		spin_unlock(&release_lock);
1955 
1956 		/* wait for synchronous usb calls to return */
1957 		if (mos_parport->msg_pending)
1958 			wait_for_completion_timeout(&mos_parport->syncmsg_compl,
1959 					    msecs_to_jiffies(MOS_WDR_TIMEOUT));
1960 
1961 		parport_remove_port(mos_parport->pp);
1962 		usb_set_serial_data(serial, NULL);
1963 		mos_parport->serial = NULL;
1964 
1965 		/* if tasklet currently scheduled, wait for it to complete */
1966 		tasklet_kill(&mos_parport->urb_tasklet);
1967 
1968 		/* unlink any urbs sent by the tasklet  */
1969 		spin_lock_irqsave(&mos_parport->listlock, flags);
1970 		list_for_each_entry(urbtrack,
1971 				    &mos_parport->active_urbs,
1972 				    urblist_entry)
1973 			usb_unlink_urb(urbtrack->urb);
1974 		spin_unlock_irqrestore(&mos_parport->listlock, flags);
1975 		parport_del_port(mos_parport->pp);
1976 
1977 		kref_put(&mos_parport->ref_count, destroy_mos_parport);
1978 	}
1979 #endif
1980 }
1981 
1982 static int mos7720_port_probe(struct usb_serial_port *port)
1983 {
1984 	struct moschip_port *mos7720_port;
1985 
1986 	mos7720_port = kzalloc(sizeof(*mos7720_port), GFP_KERNEL);
1987 	if (!mos7720_port)
1988 		return -ENOMEM;
1989 
1990 	mos7720_port->port = port;
1991 
1992 	usb_set_serial_port_data(port, mos7720_port);
1993 
1994 	return 0;
1995 }
1996 
1997 static int mos7720_port_remove(struct usb_serial_port *port)
1998 {
1999 	struct moschip_port *mos7720_port;
2000 
2001 	mos7720_port = usb_get_serial_port_data(port);
2002 	kfree(mos7720_port);
2003 
2004 	return 0;
2005 }
2006 
2007 static struct usb_serial_driver moschip7720_2port_driver = {
2008 	.driver = {
2009 		.owner =	THIS_MODULE,
2010 		.name =		"moschip7720",
2011 	},
2012 	.description		= "Moschip 2 port adapter",
2013 	.id_table		= id_table,
2014 	.num_bulk_in		= 2,
2015 	.num_bulk_out		= 2,
2016 	.num_interrupt_in	= 1,
2017 	.calc_num_ports		= mos77xx_calc_num_ports,
2018 	.open			= mos7720_open,
2019 	.close			= mos7720_close,
2020 	.throttle		= mos7720_throttle,
2021 	.unthrottle		= mos7720_unthrottle,
2022 	.attach			= mos7720_startup,
2023 	.release		= mos7720_release,
2024 	.port_probe		= mos7720_port_probe,
2025 	.port_remove		= mos7720_port_remove,
2026 	.ioctl			= mos7720_ioctl,
2027 	.tiocmget		= mos7720_tiocmget,
2028 	.tiocmset		= mos7720_tiocmset,
2029 	.set_termios		= mos7720_set_termios,
2030 	.write			= mos7720_write,
2031 	.write_room		= mos7720_write_room,
2032 	.chars_in_buffer	= mos7720_chars_in_buffer,
2033 	.break_ctl		= mos7720_break,
2034 	.read_bulk_callback	= mos7720_bulk_in_callback,
2035 	.read_int_callback	= mos7720_interrupt_callback,
2036 };
2037 
2038 static struct usb_serial_driver * const serial_drivers[] = {
2039 	&moschip7720_2port_driver, NULL
2040 };
2041 
2042 module_usb_serial_driver(serial_drivers, id_table);
2043 
2044 MODULE_AUTHOR(DRIVER_AUTHOR);
2045 MODULE_DESCRIPTION(DRIVER_DESC);
2046 MODULE_LICENSE("GPL");
2047