xref: /openbmc/linux/drivers/usb/serial/mos7720.c (revision f7777dcc)
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 #define DRIVER_AUTHOR "Aspire Communications pvt Ltd."
40 #define DRIVER_DESC "Moschip USB Serial Driver"
41 
42 /* default urb timeout */
43 #define MOS_WDR_TIMEOUT	5000
44 
45 #define MOS_MAX_PORT	0x02
46 #define MOS_WRITE	0x0E
47 #define MOS_READ	0x0D
48 
49 /* Interrupt Rotinue Defines	*/
50 #define SERIAL_IIR_RLS	0x06
51 #define SERIAL_IIR_RDA	0x04
52 #define SERIAL_IIR_CTI	0x0c
53 #define SERIAL_IIR_THR	0x02
54 #define SERIAL_IIR_MS	0x00
55 
56 #define NUM_URBS			16	/* URB Count */
57 #define URB_TRANSFER_BUFFER_SIZE	32	/* URB Size */
58 
59 /* This structure holds all of the local serial port information */
60 struct moschip_port {
61 	__u8	shadowLCR;		/* last LCR value received */
62 	__u8	shadowMCR;		/* last MCR value received */
63 	__u8	shadowMSR;		/* last MSR value received */
64 	char			open;
65 	struct usb_serial_port	*port;	/* loop back to the owner */
66 	struct urb		*write_urb_pool[NUM_URBS];
67 };
68 
69 static struct usb_serial_driver moschip7720_2port_driver;
70 
71 #define USB_VENDOR_ID_MOSCHIP		0x9710
72 #define MOSCHIP_DEVICE_ID_7720		0x7720
73 #define MOSCHIP_DEVICE_ID_7715		0x7715
74 
75 static const struct usb_device_id id_table[] = {
76 	{ USB_DEVICE(USB_VENDOR_ID_MOSCHIP, MOSCHIP_DEVICE_ID_7720) },
77 	{ USB_DEVICE(USB_VENDOR_ID_MOSCHIP, MOSCHIP_DEVICE_ID_7715) },
78 	{ } /* terminating entry */
79 };
80 MODULE_DEVICE_TABLE(usb, id_table);
81 
82 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
83 
84 /* initial values for parport regs */
85 #define DCR_INIT_VAL       0x0c	/* SLCTIN, nINIT */
86 #define ECR_INIT_VAL       0x00	/* SPP mode */
87 
88 struct urbtracker {
89 	struct mos7715_parport  *mos_parport;
90 	struct list_head        urblist_entry;
91 	struct kref             ref_count;
92 	struct urb              *urb;
93 	struct usb_ctrlrequest	*setup;
94 };
95 
96 enum mos7715_pp_modes {
97 	SPP = 0<<5,
98 	PS2 = 1<<5,      /* moschip calls this 'NIBBLE' mode */
99 	PPF = 2<<5,	 /* moschip calls this 'CB-FIFO mode */
100 };
101 
102 struct mos7715_parport {
103 	struct parport          *pp;	       /* back to containing struct */
104 	struct kref             ref_count;     /* to instance of this struct */
105 	struct list_head        deferred_urbs; /* list deferred async urbs */
106 	struct list_head        active_urbs;   /* list async urbs in flight */
107 	spinlock_t              listlock;      /* protects list access */
108 	bool                    msg_pending;   /* usb sync call pending */
109 	struct completion       syncmsg_compl; /* usb sync call completed */
110 	struct tasklet_struct   urb_tasklet;   /* for sending deferred urbs */
111 	struct usb_serial       *serial;       /* back to containing struct */
112 	__u8	                shadowECR;     /* parallel port regs... */
113 	__u8	                shadowDCR;
114 	atomic_t                shadowDSR;     /* updated in int-in callback */
115 };
116 
117 /* lock guards against dereferencing NULL ptr in parport ops callbacks */
118 static DEFINE_SPINLOCK(release_lock);
119 
120 #endif	/* CONFIG_USB_SERIAL_MOS7715_PARPORT */
121 
122 static const unsigned int dummy; /* for clarity in register access fns */
123 
124 enum mos_regs {
125 	THR,	          /* serial port regs */
126 	RHR,
127 	IER,
128 	FCR,
129 	ISR,
130 	LCR,
131 	MCR,
132 	LSR,
133 	MSR,
134 	SPR,
135 	DLL,
136 	DLM,
137 	DPR,              /* parallel port regs */
138 	DSR,
139 	DCR,
140 	ECR,
141 	SP1_REG,          /* device control regs */
142 	SP2_REG,          /* serial port 2 (7720 only) */
143 	PP_REG,
144 	SP_CONTROL_REG,
145 };
146 
147 /*
148  * Return the correct value for the Windex field of the setup packet
149  * for a control endpoint message.  See the 7715 datasheet.
150  */
151 static inline __u16 get_reg_index(enum mos_regs reg)
152 {
153 	static const __u16 mos7715_index_lookup_table[] = {
154 		0x00,		/* THR */
155 		0x00,		/* RHR */
156 		0x01,		/* IER */
157 		0x02,		/* FCR */
158 		0x02,		/* ISR */
159 		0x03,		/* LCR */
160 		0x04,		/* MCR */
161 		0x05,		/* LSR */
162 		0x06,		/* MSR */
163 		0x07,		/* SPR */
164 		0x00,		/* DLL */
165 		0x01,		/* DLM */
166 		0x00,		/* DPR */
167 		0x01,		/* DSR */
168 		0x02,		/* DCR */
169 		0x0a,		/* ECR */
170 		0x01,		/* SP1_REG */
171 		0x02,		/* SP2_REG (7720 only) */
172 		0x04,		/* PP_REG (7715 only) */
173 		0x08,		/* SP_CONTROL_REG */
174 	};
175 	return mos7715_index_lookup_table[reg];
176 }
177 
178 /*
179  * Return the correct value for the upper byte of the Wvalue field of
180  * the setup packet for a control endpoint message.
181  */
182 static inline __u16 get_reg_value(enum mos_regs reg,
183 				  unsigned int serial_portnum)
184 {
185 	if (reg >= SP1_REG)	      /* control reg */
186 		return 0x0000;
187 
188 	else if (reg >= DPR)	      /* parallel port reg (7715 only) */
189 		return 0x0100;
190 
191 	else			      /* serial port reg */
192 		return (serial_portnum + 2) << 8;
193 }
194 
195 /*
196  * Write data byte to the specified device register.  The data is embedded in
197  * the value field of the setup packet. serial_portnum is ignored for registers
198  * not specific to a particular serial port.
199  */
200 static int write_mos_reg(struct usb_serial *serial, unsigned int serial_portnum,
201 			 enum mos_regs reg, __u8 data)
202 {
203 	struct usb_device *usbdev = serial->dev;
204 	unsigned int pipe = usb_sndctrlpipe(usbdev, 0);
205 	__u8 request = (__u8)0x0e;
206 	__u8 requesttype = (__u8)0x40;
207 	__u16 index = get_reg_index(reg);
208 	__u16 value = get_reg_value(reg, serial_portnum) + data;
209 	int status = usb_control_msg(usbdev, pipe, request, requesttype, value,
210 				     index, NULL, 0, MOS_WDR_TIMEOUT);
211 	if (status < 0)
212 		dev_err(&usbdev->dev,
213 			"mos7720: usb_control_msg() failed: %d", status);
214 	return status;
215 }
216 
217 /*
218  * Read data byte from the specified device register.  The data returned by the
219  * device is embedded in the value field of the setup packet.  serial_portnum is
220  * ignored for registers that are not specific to a particular serial port.
221  */
222 static int read_mos_reg(struct usb_serial *serial, unsigned int serial_portnum,
223 			enum mos_regs reg, __u8 *data)
224 {
225 	struct usb_device *usbdev = serial->dev;
226 	unsigned int pipe = usb_rcvctrlpipe(usbdev, 0);
227 	__u8 request = (__u8)0x0d;
228 	__u8 requesttype = (__u8)0xc0;
229 	__u16 index = get_reg_index(reg);
230 	__u16 value = get_reg_value(reg, serial_portnum);
231 	u8 *buf;
232 	int status;
233 
234 	buf = kmalloc(1, GFP_KERNEL);
235 	if (!buf)
236 		return -ENOMEM;
237 
238 	status = usb_control_msg(usbdev, pipe, request, requesttype, value,
239 				     index, buf, 1, MOS_WDR_TIMEOUT);
240 	if (status == 1)
241 		*data = *buf;
242 	else if (status < 0)
243 		dev_err(&usbdev->dev,
244 			"mos7720: usb_control_msg() failed: %d", status);
245 	kfree(buf);
246 
247 	return status;
248 }
249 
250 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
251 
252 static inline int mos7715_change_mode(struct mos7715_parport *mos_parport,
253 				      enum mos7715_pp_modes mode)
254 {
255 	mos_parport->shadowECR = mode;
256 	write_mos_reg(mos_parport->serial, dummy, ECR, mos_parport->shadowECR);
257 	return 0;
258 }
259 
260 static void destroy_mos_parport(struct kref *kref)
261 {
262 	struct mos7715_parport *mos_parport =
263 		container_of(kref, struct mos7715_parport, ref_count);
264 
265 	kfree(mos_parport);
266 }
267 
268 static void destroy_urbtracker(struct kref *kref)
269 {
270 	struct urbtracker *urbtrack =
271 		container_of(kref, struct urbtracker, ref_count);
272 	struct mos7715_parport *mos_parport = urbtrack->mos_parport;
273 
274 	usb_free_urb(urbtrack->urb);
275 	kfree(urbtrack->setup);
276 	kfree(urbtrack);
277 	kref_put(&mos_parport->ref_count, destroy_mos_parport);
278 }
279 
280 /*
281  * This runs as a tasklet when sending an urb in a non-blocking parallel
282  * port callback had to be deferred because the disconnect mutex could not be
283  * obtained at the time.
284  */
285 static void send_deferred_urbs(unsigned long _mos_parport)
286 {
287 	int ret_val;
288 	unsigned long flags;
289 	struct mos7715_parport *mos_parport = (void *)_mos_parport;
290 	struct urbtracker *urbtrack, *tmp;
291 	struct list_head *cursor, *next;
292 	struct device *dev;
293 
294 	/* if release function ran, game over */
295 	if (unlikely(mos_parport->serial == NULL))
296 		return;
297 
298 	dev = &mos_parport->serial->dev->dev;
299 
300 	/* try again to get the mutex */
301 	if (!mutex_trylock(&mos_parport->serial->disc_mutex)) {
302 		dev_dbg(dev, "%s: rescheduling tasklet\n", __func__);
303 		tasklet_schedule(&mos_parport->urb_tasklet);
304 		return;
305 	}
306 
307 	/* if device disconnected, game over */
308 	if (unlikely(mos_parport->serial->disconnected)) {
309 		mutex_unlock(&mos_parport->serial->disc_mutex);
310 		return;
311 	}
312 
313 	spin_lock_irqsave(&mos_parport->listlock, flags);
314 	if (list_empty(&mos_parport->deferred_urbs)) {
315 		spin_unlock_irqrestore(&mos_parport->listlock, flags);
316 		mutex_unlock(&mos_parport->serial->disc_mutex);
317 		dev_dbg(dev, "%s: deferred_urbs list empty\n", __func__);
318 		return;
319 	}
320 
321 	/* move contents of deferred_urbs list to active_urbs list and submit */
322 	list_for_each_safe(cursor, next, &mos_parport->deferred_urbs)
323 		list_move_tail(cursor, &mos_parport->active_urbs);
324 	list_for_each_entry_safe(urbtrack, tmp, &mos_parport->active_urbs,
325 			    urblist_entry) {
326 		ret_val = usb_submit_urb(urbtrack->urb, GFP_ATOMIC);
327 		dev_dbg(dev, "%s: urb submitted\n", __func__);
328 		if (ret_val) {
329 			dev_err(dev, "usb_submit_urb() failed: %d\n", ret_val);
330 			list_del(&urbtrack->urblist_entry);
331 			kref_put(&urbtrack->ref_count, destroy_urbtracker);
332 		}
333 	}
334 	spin_unlock_irqrestore(&mos_parport->listlock, flags);
335 	mutex_unlock(&mos_parport->serial->disc_mutex);
336 }
337 
338 /* callback for parallel port control urbs submitted asynchronously */
339 static void async_complete(struct urb *urb)
340 {
341 	struct urbtracker *urbtrack = urb->context;
342 	int status = urb->status;
343 
344 	if (unlikely(status))
345 		dev_dbg(&urb->dev->dev, "%s - nonzero urb status received: %d\n", __func__, status);
346 
347 	/* remove the urbtracker from the active_urbs list */
348 	spin_lock(&urbtrack->mos_parport->listlock);
349 	list_del(&urbtrack->urblist_entry);
350 	spin_unlock(&urbtrack->mos_parport->listlock);
351 	kref_put(&urbtrack->ref_count, destroy_urbtracker);
352 }
353 
354 static int write_parport_reg_nonblock(struct mos7715_parport *mos_parport,
355 				      enum mos_regs reg, __u8 data)
356 {
357 	struct urbtracker *urbtrack;
358 	int ret_val;
359 	unsigned long flags;
360 	struct usb_serial *serial = mos_parport->serial;
361 	struct usb_device *usbdev = serial->dev;
362 
363 	/* create and initialize the control urb and containing urbtracker */
364 	urbtrack = kmalloc(sizeof(struct urbtracker), GFP_ATOMIC);
365 	if (urbtrack == NULL) {
366 		dev_err(&usbdev->dev, "out of memory");
367 		return -ENOMEM;
368 	}
369 	kref_get(&mos_parport->ref_count);
370 	urbtrack->mos_parport = mos_parport;
371 	urbtrack->urb = usb_alloc_urb(0, GFP_ATOMIC);
372 	if (urbtrack->urb == NULL) {
373 		dev_err(&usbdev->dev, "out of urbs");
374 		kfree(urbtrack);
375 		return -ENOMEM;
376 	}
377 	urbtrack->setup = kmalloc(sizeof(*urbtrack->setup), GFP_ATOMIC);
378 	if (!urbtrack->setup) {
379 		usb_free_urb(urbtrack->urb);
380 		kfree(urbtrack);
381 		return -ENOMEM;
382 	}
383 	urbtrack->setup->bRequestType = (__u8)0x40;
384 	urbtrack->setup->bRequest = (__u8)0x0e;
385 	urbtrack->setup->wValue = cpu_to_le16(get_reg_value(reg, dummy));
386 	urbtrack->setup->wIndex = cpu_to_le16(get_reg_index(reg));
387 	urbtrack->setup->wLength = 0;
388 	usb_fill_control_urb(urbtrack->urb, usbdev,
389 			     usb_sndctrlpipe(usbdev, 0),
390 			     (unsigned char *)urbtrack->setup,
391 			     NULL, 0, async_complete, urbtrack);
392 	kref_init(&urbtrack->ref_count);
393 	INIT_LIST_HEAD(&urbtrack->urblist_entry);
394 
395 	/*
396 	 * get the disconnect mutex, or add tracker to the deferred_urbs list
397 	 * and schedule a tasklet to try again later
398 	 */
399 	if (!mutex_trylock(&serial->disc_mutex)) {
400 		spin_lock_irqsave(&mos_parport->listlock, flags);
401 		list_add_tail(&urbtrack->urblist_entry,
402 			      &mos_parport->deferred_urbs);
403 		spin_unlock_irqrestore(&mos_parport->listlock, flags);
404 		tasklet_schedule(&mos_parport->urb_tasklet);
405 		dev_dbg(&usbdev->dev, "tasklet scheduled");
406 		return 0;
407 	}
408 
409 	/* bail if device disconnected */
410 	if (serial->disconnected) {
411 		kref_put(&urbtrack->ref_count, destroy_urbtracker);
412 		mutex_unlock(&serial->disc_mutex);
413 		return -ENODEV;
414 	}
415 
416 	/* add the tracker to the active_urbs list and submit */
417 	spin_lock_irqsave(&mos_parport->listlock, flags);
418 	list_add_tail(&urbtrack->urblist_entry, &mos_parport->active_urbs);
419 	spin_unlock_irqrestore(&mos_parport->listlock, flags);
420 	ret_val = usb_submit_urb(urbtrack->urb, GFP_ATOMIC);
421 	mutex_unlock(&serial->disc_mutex);
422 	if (ret_val) {
423 		dev_err(&usbdev->dev,
424 			"%s: submit_urb() failed: %d", __func__, ret_val);
425 		spin_lock_irqsave(&mos_parport->listlock, flags);
426 		list_del(&urbtrack->urblist_entry);
427 		spin_unlock_irqrestore(&mos_parport->listlock, flags);
428 		kref_put(&urbtrack->ref_count, destroy_urbtracker);
429 		return ret_val;
430 	}
431 	return 0;
432 }
433 
434 /*
435  * This is the the common top part of all parallel port callback operations that
436  * send synchronous messages to the device.  This implements convoluted locking
437  * that avoids two scenarios: (1) a port operation is called after usbserial
438  * has called our release function, at which point struct mos7715_parport has
439  * been destroyed, and (2) the device has been disconnected, but usbserial has
440  * not called the release function yet because someone has a serial port open.
441  * The shared release_lock prevents the first, and the mutex and disconnected
442  * flag maintained by usbserial covers the second.  We also use the msg_pending
443  * flag to ensure that all synchronous usb messgage calls have completed before
444  * our release function can return.
445  */
446 static int parport_prologue(struct parport *pp)
447 {
448 	struct mos7715_parport *mos_parport;
449 
450 	spin_lock(&release_lock);
451 	mos_parport = pp->private_data;
452 	if (unlikely(mos_parport == NULL)) {
453 		/* release fn called, port struct destroyed */
454 		spin_unlock(&release_lock);
455 		return -1;
456 	}
457 	mos_parport->msg_pending = true;   /* synch usb call pending */
458 	INIT_COMPLETION(mos_parport->syncmsg_compl);
459 	spin_unlock(&release_lock);
460 
461 	mutex_lock(&mos_parport->serial->disc_mutex);
462 	if (mos_parport->serial->disconnected) {
463 		/* device disconnected */
464 		mutex_unlock(&mos_parport->serial->disc_mutex);
465 		mos_parport->msg_pending = false;
466 		complete(&mos_parport->syncmsg_compl);
467 		return -1;
468 	}
469 
470 	return 0;
471 }
472 
473 /*
474  * This is the the common bottom part of all parallel port functions that send
475  * synchronous messages to the device.
476  */
477 static inline void parport_epilogue(struct parport *pp)
478 {
479 	struct mos7715_parport *mos_parport = pp->private_data;
480 	mutex_unlock(&mos_parport->serial->disc_mutex);
481 	mos_parport->msg_pending = false;
482 	complete(&mos_parport->syncmsg_compl);
483 }
484 
485 static void parport_mos7715_write_data(struct parport *pp, unsigned char d)
486 {
487 	struct mos7715_parport *mos_parport = pp->private_data;
488 
489 	if (parport_prologue(pp) < 0)
490 		return;
491 	mos7715_change_mode(mos_parport, SPP);
492 	write_mos_reg(mos_parport->serial, dummy, DPR, (__u8)d);
493 	parport_epilogue(pp);
494 }
495 
496 static unsigned char parport_mos7715_read_data(struct parport *pp)
497 {
498 	struct mos7715_parport *mos_parport = pp->private_data;
499 	unsigned char d;
500 
501 	if (parport_prologue(pp) < 0)
502 		return 0;
503 	read_mos_reg(mos_parport->serial, dummy, DPR, &d);
504 	parport_epilogue(pp);
505 	return d;
506 }
507 
508 static void parport_mos7715_write_control(struct parport *pp, unsigned char d)
509 {
510 	struct mos7715_parport *mos_parport = pp->private_data;
511 	__u8 data;
512 
513 	if (parport_prologue(pp) < 0)
514 		return;
515 	data = ((__u8)d & 0x0f) | (mos_parport->shadowDCR & 0xf0);
516 	write_mos_reg(mos_parport->serial, dummy, DCR, data);
517 	mos_parport->shadowDCR = data;
518 	parport_epilogue(pp);
519 }
520 
521 static unsigned char parport_mos7715_read_control(struct parport *pp)
522 {
523 	struct mos7715_parport *mos_parport = pp->private_data;
524 	__u8 dcr;
525 
526 	spin_lock(&release_lock);
527 	mos_parport = pp->private_data;
528 	if (unlikely(mos_parport == NULL)) {
529 		spin_unlock(&release_lock);
530 		return 0;
531 	}
532 	dcr = mos_parport->shadowDCR & 0x0f;
533 	spin_unlock(&release_lock);
534 	return dcr;
535 }
536 
537 static unsigned char parport_mos7715_frob_control(struct parport *pp,
538 						  unsigned char mask,
539 						  unsigned char val)
540 {
541 	struct mos7715_parport *mos_parport = pp->private_data;
542 	__u8 dcr;
543 
544 	mask &= 0x0f;
545 	val &= 0x0f;
546 	if (parport_prologue(pp) < 0)
547 		return 0;
548 	mos_parport->shadowDCR = (mos_parport->shadowDCR & (~mask)) ^ val;
549 	write_mos_reg(mos_parport->serial, dummy, DCR, mos_parport->shadowDCR);
550 	dcr = mos_parport->shadowDCR & 0x0f;
551 	parport_epilogue(pp);
552 	return dcr;
553 }
554 
555 static unsigned char parport_mos7715_read_status(struct parport *pp)
556 {
557 	unsigned char status;
558 	struct mos7715_parport *mos_parport = pp->private_data;
559 
560 	spin_lock(&release_lock);
561 	mos_parport = pp->private_data;
562 	if (unlikely(mos_parport == NULL)) {	/* release called */
563 		spin_unlock(&release_lock);
564 		return 0;
565 	}
566 	status = atomic_read(&mos_parport->shadowDSR) & 0xf8;
567 	spin_unlock(&release_lock);
568 	return status;
569 }
570 
571 static void parport_mos7715_enable_irq(struct parport *pp)
572 {
573 }
574 
575 static void parport_mos7715_disable_irq(struct parport *pp)
576 {
577 }
578 
579 static void parport_mos7715_data_forward(struct parport *pp)
580 {
581 	struct mos7715_parport *mos_parport = pp->private_data;
582 
583 	if (parport_prologue(pp) < 0)
584 		return;
585 	mos7715_change_mode(mos_parport, PS2);
586 	mos_parport->shadowDCR &=  ~0x20;
587 	write_mos_reg(mos_parport->serial, dummy, DCR, mos_parport->shadowDCR);
588 	parport_epilogue(pp);
589 }
590 
591 static void parport_mos7715_data_reverse(struct parport *pp)
592 {
593 	struct mos7715_parport *mos_parport = pp->private_data;
594 
595 	if (parport_prologue(pp) < 0)
596 		return;
597 	mos7715_change_mode(mos_parport, PS2);
598 	mos_parport->shadowDCR |= 0x20;
599 	write_mos_reg(mos_parport->serial, dummy, DCR, mos_parport->shadowDCR);
600 	parport_epilogue(pp);
601 }
602 
603 static void parport_mos7715_init_state(struct pardevice *dev,
604 				       struct parport_state *s)
605 {
606 	s->u.pc.ctr = DCR_INIT_VAL;
607 	s->u.pc.ecr = ECR_INIT_VAL;
608 }
609 
610 /* N.B. Parport core code requires that this function not block */
611 static void parport_mos7715_save_state(struct parport *pp,
612 				       struct parport_state *s)
613 {
614 	struct mos7715_parport *mos_parport;
615 
616 	spin_lock(&release_lock);
617 	mos_parport = pp->private_data;
618 	if (unlikely(mos_parport == NULL)) {	/* release called */
619 		spin_unlock(&release_lock);
620 		return;
621 	}
622 	s->u.pc.ctr = mos_parport->shadowDCR;
623 	s->u.pc.ecr = mos_parport->shadowECR;
624 	spin_unlock(&release_lock);
625 }
626 
627 /* N.B. Parport core code requires that this function not block */
628 static void parport_mos7715_restore_state(struct parport *pp,
629 					  struct parport_state *s)
630 {
631 	struct mos7715_parport *mos_parport;
632 
633 	spin_lock(&release_lock);
634 	mos_parport = pp->private_data;
635 	if (unlikely(mos_parport == NULL)) {	/* release called */
636 		spin_unlock(&release_lock);
637 		return;
638 	}
639 	write_parport_reg_nonblock(mos_parport, DCR, mos_parport->shadowDCR);
640 	write_parport_reg_nonblock(mos_parport, ECR, mos_parport->shadowECR);
641 	spin_unlock(&release_lock);
642 }
643 
644 static size_t parport_mos7715_write_compat(struct parport *pp,
645 					   const void *buffer,
646 					   size_t len, int flags)
647 {
648 	int retval;
649 	struct mos7715_parport *mos_parport = pp->private_data;
650 	int actual_len;
651 
652 	if (parport_prologue(pp) < 0)
653 		return 0;
654 	mos7715_change_mode(mos_parport, PPF);
655 	retval = usb_bulk_msg(mos_parport->serial->dev,
656 			      usb_sndbulkpipe(mos_parport->serial->dev, 2),
657 			      (void *)buffer, len, &actual_len,
658 			      MOS_WDR_TIMEOUT);
659 	parport_epilogue(pp);
660 	if (retval) {
661 		dev_err(&mos_parport->serial->dev->dev,
662 			"mos7720: usb_bulk_msg() failed: %d", retval);
663 		return 0;
664 	}
665 	return actual_len;
666 }
667 
668 static struct parport_operations parport_mos7715_ops = {
669 	.owner =		THIS_MODULE,
670 	.write_data =		parport_mos7715_write_data,
671 	.read_data =		parport_mos7715_read_data,
672 
673 	.write_control =	parport_mos7715_write_control,
674 	.read_control =		parport_mos7715_read_control,
675 	.frob_control =		parport_mos7715_frob_control,
676 
677 	.read_status =		parport_mos7715_read_status,
678 
679 	.enable_irq =		parport_mos7715_enable_irq,
680 	.disable_irq =		parport_mos7715_disable_irq,
681 
682 	.data_forward =		parport_mos7715_data_forward,
683 	.data_reverse =		parport_mos7715_data_reverse,
684 
685 	.init_state =		parport_mos7715_init_state,
686 	.save_state =		parport_mos7715_save_state,
687 	.restore_state =	parport_mos7715_restore_state,
688 
689 	.compat_write_data =	parport_mos7715_write_compat,
690 
691 	.nibble_read_data =	parport_ieee1284_read_nibble,
692 	.byte_read_data =	parport_ieee1284_read_byte,
693 };
694 
695 /*
696  * Allocate and initialize parallel port control struct, initialize
697  * the parallel port hardware device, and register with the parport subsystem.
698  */
699 static int mos7715_parport_init(struct usb_serial *serial)
700 {
701 	struct mos7715_parport *mos_parport;
702 
703 	/* allocate and initialize parallel port control struct */
704 	mos_parport = kzalloc(sizeof(struct mos7715_parport), GFP_KERNEL);
705 	if (mos_parport == NULL) {
706 		dev_dbg(&serial->dev->dev, "%s: kzalloc failed\n", __func__);
707 		return -ENOMEM;
708 	}
709 	mos_parport->msg_pending = false;
710 	kref_init(&mos_parport->ref_count);
711 	spin_lock_init(&mos_parport->listlock);
712 	INIT_LIST_HEAD(&mos_parport->active_urbs);
713 	INIT_LIST_HEAD(&mos_parport->deferred_urbs);
714 	usb_set_serial_data(serial, mos_parport); /* hijack private pointer */
715 	mos_parport->serial = serial;
716 	tasklet_init(&mos_parport->urb_tasklet, send_deferred_urbs,
717 		     (unsigned long) mos_parport);
718 	init_completion(&mos_parport->syncmsg_compl);
719 
720 	/* cycle parallel port reset bit */
721 	write_mos_reg(mos_parport->serial, dummy, PP_REG, (__u8)0x80);
722 	write_mos_reg(mos_parport->serial, dummy, PP_REG, (__u8)0x00);
723 
724 	/* initialize device registers */
725 	mos_parport->shadowDCR = DCR_INIT_VAL;
726 	write_mos_reg(mos_parport->serial, dummy, DCR, mos_parport->shadowDCR);
727 	mos_parport->shadowECR = ECR_INIT_VAL;
728 	write_mos_reg(mos_parport->serial, dummy, ECR, mos_parport->shadowECR);
729 
730 	/* register with parport core */
731 	mos_parport->pp = parport_register_port(0, PARPORT_IRQ_NONE,
732 						PARPORT_DMA_NONE,
733 						&parport_mos7715_ops);
734 	if (mos_parport->pp == NULL) {
735 		dev_err(&serial->interface->dev,
736 			"Could not register parport\n");
737 		kref_put(&mos_parport->ref_count, destroy_mos_parport);
738 		return -EIO;
739 	}
740 	mos_parport->pp->private_data = mos_parport;
741 	mos_parport->pp->modes = PARPORT_MODE_COMPAT | PARPORT_MODE_PCSPP;
742 	mos_parport->pp->dev = &serial->interface->dev;
743 	parport_announce_port(mos_parport->pp);
744 
745 	return 0;
746 }
747 #endif	/* CONFIG_USB_SERIAL_MOS7715_PARPORT */
748 
749 /*
750  * mos7720_interrupt_callback
751  *	this is the callback function for when we have received data on the
752  *	interrupt endpoint.
753  */
754 static void mos7720_interrupt_callback(struct urb *urb)
755 {
756 	int result;
757 	int length;
758 	int status = urb->status;
759 	struct device *dev = &urb->dev->dev;
760 	__u8 *data;
761 	__u8 sp1;
762 	__u8 sp2;
763 
764 	switch (status) {
765 	case 0:
766 		/* success */
767 		break;
768 	case -ECONNRESET:
769 	case -ENOENT:
770 	case -ESHUTDOWN:
771 		/* this urb is terminated, clean up */
772 		dev_dbg(dev, "%s - urb shutting down with status: %d\n", __func__, status);
773 		return;
774 	default:
775 		dev_dbg(dev, "%s - nonzero urb status received: %d\n", __func__, status);
776 		goto exit;
777 	}
778 
779 	length = urb->actual_length;
780 	data = urb->transfer_buffer;
781 
782 	/* Moschip get 4 bytes
783 	 * Byte 1 IIR Port 1 (port.number is 0)
784 	 * Byte 2 IIR Port 2 (port.number is 1)
785 	 * Byte 3 --------------
786 	 * Byte 4 FIFO status for both */
787 
788 	/* the above description is inverted
789 	 * 	oneukum 2007-03-14 */
790 
791 	if (unlikely(length != 4)) {
792 		dev_dbg(dev, "Wrong data !!!\n");
793 		return;
794 	}
795 
796 	sp1 = data[3];
797 	sp2 = data[2];
798 
799 	if ((sp1 | sp2) & 0x01) {
800 		/* No Interrupt Pending in both the ports */
801 		dev_dbg(dev, "No Interrupt !!!\n");
802 	} else {
803 		switch (sp1 & 0x0f) {
804 		case SERIAL_IIR_RLS:
805 			dev_dbg(dev, "Serial Port 1: Receiver status error or address bit detected in 9-bit mode\n");
806 			break;
807 		case SERIAL_IIR_CTI:
808 			dev_dbg(dev, "Serial Port 1: Receiver time out\n");
809 			break;
810 		case SERIAL_IIR_MS:
811 			/* dev_dbg(dev, "Serial Port 1: Modem status change\n"); */
812 			break;
813 		}
814 
815 		switch (sp2 & 0x0f) {
816 		case SERIAL_IIR_RLS:
817 			dev_dbg(dev, "Serial Port 2: Receiver status error or address bit detected in 9-bit mode\n");
818 			break;
819 		case SERIAL_IIR_CTI:
820 			dev_dbg(dev, "Serial Port 2: Receiver time out\n");
821 			break;
822 		case SERIAL_IIR_MS:
823 			/* dev_dbg(dev, "Serial Port 2: Modem status change\n"); */
824 			break;
825 		}
826 	}
827 
828 exit:
829 	result = usb_submit_urb(urb, GFP_ATOMIC);
830 	if (result)
831 		dev_err(dev, "%s - Error %d submitting control urb\n", __func__, result);
832 }
833 
834 /*
835  * mos7715_interrupt_callback
836  *	this is the 7715's callback function for when we have received data on
837  *	the interrupt endpoint.
838  */
839 static void mos7715_interrupt_callback(struct urb *urb)
840 {
841 	int result;
842 	int length;
843 	int status = urb->status;
844 	struct device *dev = &urb->dev->dev;
845 	__u8 *data;
846 	__u8 iir;
847 
848 	switch (status) {
849 	case 0:
850 		/* success */
851 		break;
852 	case -ECONNRESET:
853 	case -ENOENT:
854 	case -ESHUTDOWN:
855 	case -ENODEV:
856 		/* this urb is terminated, clean up */
857 		dev_dbg(dev, "%s - urb shutting down with status: %d\n", __func__, status);
858 		return;
859 	default:
860 		dev_dbg(dev, "%s - nonzero urb status received: %d\n", __func__, status);
861 		goto exit;
862 	}
863 
864 	length = urb->actual_length;
865 	data = urb->transfer_buffer;
866 
867 	/* Structure of data from 7715 device:
868 	 * Byte 1: IIR serial Port
869 	 * Byte 2: unused
870 	 * Byte 2: DSR parallel port
871 	 * Byte 4: FIFO status for both */
872 
873 	if (unlikely(length != 4)) {
874 		dev_dbg(dev, "Wrong data !!!\n");
875 		return;
876 	}
877 
878 	iir = data[0];
879 	if (!(iir & 0x01)) {	/* serial port interrupt pending */
880 		switch (iir & 0x0f) {
881 		case SERIAL_IIR_RLS:
882 			dev_dbg(dev, "Serial Port: Receiver status error or address bit detected in 9-bit mode\n\n");
883 			break;
884 		case SERIAL_IIR_CTI:
885 			dev_dbg(dev, "Serial Port: Receiver time out\n");
886 			break;
887 		case SERIAL_IIR_MS:
888 			/* dev_dbg(dev, "Serial Port: Modem status change\n"); */
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(dev, "%s - Error %d submitting control urb\n", __func__, result);
907 }
908 
909 /*
910  * mos7720_bulk_in_callback
911  *	this is the callback function for when we have received data on the
912  *	bulk in endpoint.
913  */
914 static void mos7720_bulk_in_callback(struct urb *urb)
915 {
916 	int retval;
917 	unsigned char *data ;
918 	struct usb_serial_port *port;
919 	int status = urb->status;
920 
921 	if (status) {
922 		dev_dbg(&urb->dev->dev, "nonzero read bulk status received: %d\n", status);
923 		return;
924 	}
925 
926 	port = urb->context;
927 
928 	dev_dbg(&port->dev, "Entering...%s\n", __func__);
929 
930 	data = urb->transfer_buffer;
931 
932 	if (urb->actual_length) {
933 		tty_insert_flip_string(&port->port, data, urb->actual_length);
934 		tty_flip_buffer_push(&port->port);
935 	}
936 
937 	if (port->read_urb->status != -EINPROGRESS) {
938 		retval = usb_submit_urb(port->read_urb, GFP_ATOMIC);
939 		if (retval)
940 			dev_dbg(&port->dev, "usb_submit_urb(read bulk) failed, retval = %d\n", retval);
941 	}
942 }
943 
944 /*
945  * mos7720_bulk_out_data_callback
946  *	this is the callback function for when we have finished sending serial
947  *	data on the bulk out endpoint.
948  */
949 static void mos7720_bulk_out_data_callback(struct urb *urb)
950 {
951 	struct moschip_port *mos7720_port;
952 	int status = urb->status;
953 
954 	if (status) {
955 		dev_dbg(&urb->dev->dev, "nonzero write bulk status received:%d\n", status);
956 		return;
957 	}
958 
959 	mos7720_port = urb->context;
960 	if (!mos7720_port) {
961 		dev_dbg(&urb->dev->dev, "NULL mos7720_port pointer\n");
962 		return ;
963 	}
964 
965 	if (mos7720_port->open)
966 		tty_port_tty_wakeup(&mos7720_port->port->port);
967 }
968 
969 /*
970  * mos77xx_probe
971  *	this function installs the appropriate read interrupt endpoint callback
972  *	depending on whether the device is a 7720 or 7715, thus avoiding costly
973  *	run-time checks in the high-frequency callback routine itself.
974  */
975 static int mos77xx_probe(struct usb_serial *serial,
976 			 const struct usb_device_id *id)
977 {
978 	if (id->idProduct == MOSCHIP_DEVICE_ID_7715)
979 		moschip7720_2port_driver.read_int_callback =
980 			mos7715_interrupt_callback;
981 	else
982 		moschip7720_2port_driver.read_int_callback =
983 			mos7720_interrupt_callback;
984 
985 	return 0;
986 }
987 
988 static int mos77xx_calc_num_ports(struct usb_serial *serial)
989 {
990 	u16 product = le16_to_cpu(serial->dev->descriptor.idProduct);
991 	if (product == MOSCHIP_DEVICE_ID_7715)
992 		return 1;
993 
994 	return 2;
995 }
996 
997 static int mos7720_open(struct tty_struct *tty, struct usb_serial_port *port)
998 {
999 	struct usb_serial *serial;
1000 	struct urb *urb;
1001 	struct moschip_port *mos7720_port;
1002 	int response;
1003 	int port_number;
1004 	__u8 data;
1005 	int allocated_urbs = 0;
1006 	int j;
1007 
1008 	serial = port->serial;
1009 
1010 	mos7720_port = usb_get_serial_port_data(port);
1011 	if (mos7720_port == NULL)
1012 		return -ENODEV;
1013 
1014 	usb_clear_halt(serial->dev, port->write_urb->pipe);
1015 	usb_clear_halt(serial->dev, port->read_urb->pipe);
1016 
1017 	/* Initialising the write urb pool */
1018 	for (j = 0; j < NUM_URBS; ++j) {
1019 		urb = usb_alloc_urb(0, GFP_KERNEL);
1020 		mos7720_port->write_urb_pool[j] = urb;
1021 
1022 		if (urb == NULL) {
1023 			dev_err(&port->dev, "No more urbs???\n");
1024 			continue;
1025 		}
1026 
1027 		urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE,
1028 					       GFP_KERNEL);
1029 		if (!urb->transfer_buffer) {
1030 			dev_err(&port->dev,
1031 				"%s-out of memory for urb buffers.\n",
1032 				__func__);
1033 			usb_free_urb(mos7720_port->write_urb_pool[j]);
1034 			mos7720_port->write_urb_pool[j] = NULL;
1035 			continue;
1036 		}
1037 		allocated_urbs++;
1038 	}
1039 
1040 	if (!allocated_urbs)
1041 		return -ENOMEM;
1042 
1043 	 /* Initialize MCS7720 -- Write Init values to corresponding Registers
1044 	  *
1045 	  * Register Index
1046 	  * 0 : THR/RHR
1047 	  * 1 : IER
1048 	  * 2 : FCR
1049 	  * 3 : LCR
1050 	  * 4 : MCR
1051 	  * 5 : LSR
1052 	  * 6 : MSR
1053 	  * 7 : SPR
1054 	  *
1055 	  * 0x08 : SP1/2 Control Reg
1056 	  */
1057 	port_number = port->port_number;
1058 	read_mos_reg(serial, port_number, LSR, &data);
1059 
1060 	dev_dbg(&port->dev, "SS::%p LSR:%x\n", mos7720_port, data);
1061 
1062 	write_mos_reg(serial, dummy, SP1_REG, 0x02);
1063 	write_mos_reg(serial, dummy, SP2_REG, 0x02);
1064 
1065 	write_mos_reg(serial, port_number, IER, 0x00);
1066 	write_mos_reg(serial, port_number, FCR, 0x00);
1067 
1068 	write_mos_reg(serial, port_number, FCR, 0xcf);
1069 	mos7720_port->shadowLCR = 0x03;
1070 	write_mos_reg(serial, port_number, LCR, mos7720_port->shadowLCR);
1071 	mos7720_port->shadowMCR = 0x0b;
1072 	write_mos_reg(serial, port_number, MCR, mos7720_port->shadowMCR);
1073 
1074 	write_mos_reg(serial, port_number, SP_CONTROL_REG, 0x00);
1075 	read_mos_reg(serial, dummy, SP_CONTROL_REG, &data);
1076 	data = data | (port->port_number + 1);
1077 	write_mos_reg(serial, dummy, SP_CONTROL_REG, data);
1078 	mos7720_port->shadowLCR = 0x83;
1079 	write_mos_reg(serial, port_number, LCR, mos7720_port->shadowLCR);
1080 	write_mos_reg(serial, port_number, THR, 0x0c);
1081 	write_mos_reg(serial, port_number, IER, 0x00);
1082 	mos7720_port->shadowLCR = 0x03;
1083 	write_mos_reg(serial, port_number, LCR, mos7720_port->shadowLCR);
1084 	write_mos_reg(serial, port_number, IER, 0x0c);
1085 
1086 	response = usb_submit_urb(port->read_urb, GFP_KERNEL);
1087 	if (response)
1088 		dev_err(&port->dev, "%s - Error %d submitting read urb\n",
1089 							__func__, response);
1090 
1091 	/* initialize our port settings */
1092 	mos7720_port->shadowMCR = UART_MCR_OUT2; /* Must set to enable ints! */
1093 
1094 	/* send a open port command */
1095 	mos7720_port->open = 1;
1096 
1097 	return 0;
1098 }
1099 
1100 /*
1101  * mos7720_chars_in_buffer
1102  *	this function is called by the tty driver when it wants to know how many
1103  *	bytes of data we currently have outstanding in the port (data that has
1104  *	been written, but hasn't made it out the port yet)
1105  *	If successful, we return the number of bytes left to be written in the
1106  *	system,
1107  *	Otherwise we return a negative error number.
1108  */
1109 static int mos7720_chars_in_buffer(struct tty_struct *tty)
1110 {
1111 	struct usb_serial_port *port = tty->driver_data;
1112 	int i;
1113 	int chars = 0;
1114 	struct moschip_port *mos7720_port;
1115 
1116 	mos7720_port = usb_get_serial_port_data(port);
1117 	if (mos7720_port == NULL)
1118 		return 0;
1119 
1120 	for (i = 0; i < NUM_URBS; ++i) {
1121 		if (mos7720_port->write_urb_pool[i] &&
1122 		    mos7720_port->write_urb_pool[i]->status == -EINPROGRESS)
1123 			chars += URB_TRANSFER_BUFFER_SIZE;
1124 	}
1125 	dev_dbg(&port->dev, "%s - returns %d\n", __func__, chars);
1126 	return chars;
1127 }
1128 
1129 static void mos7720_close(struct usb_serial_port *port)
1130 {
1131 	struct usb_serial *serial;
1132 	struct moschip_port *mos7720_port;
1133 	int j;
1134 
1135 	serial = port->serial;
1136 
1137 	mos7720_port = usb_get_serial_port_data(port);
1138 	if (mos7720_port == NULL)
1139 		return;
1140 
1141 	for (j = 0; j < NUM_URBS; ++j)
1142 		usb_kill_urb(mos7720_port->write_urb_pool[j]);
1143 
1144 	/* Freeing Write URBs */
1145 	for (j = 0; j < NUM_URBS; ++j) {
1146 		if (mos7720_port->write_urb_pool[j]) {
1147 			kfree(mos7720_port->write_urb_pool[j]->transfer_buffer);
1148 			usb_free_urb(mos7720_port->write_urb_pool[j]);
1149 		}
1150 	}
1151 
1152 	/* While closing port, shutdown all bulk read, write  *
1153 	 * and interrupt read if they exists, otherwise nop   */
1154 	usb_kill_urb(port->write_urb);
1155 	usb_kill_urb(port->read_urb);
1156 
1157 	write_mos_reg(serial, port->port_number, MCR, 0x00);
1158 	write_mos_reg(serial, port->port_number, IER, 0x00);
1159 
1160 	mos7720_port->open = 0;
1161 }
1162 
1163 static void mos7720_break(struct tty_struct *tty, int break_state)
1164 {
1165 	struct usb_serial_port *port = tty->driver_data;
1166 	unsigned char data;
1167 	struct usb_serial *serial;
1168 	struct moschip_port *mos7720_port;
1169 
1170 	serial = port->serial;
1171 
1172 	mos7720_port = usb_get_serial_port_data(port);
1173 	if (mos7720_port == NULL)
1174 		return;
1175 
1176 	if (break_state == -1)
1177 		data = mos7720_port->shadowLCR | UART_LCR_SBC;
1178 	else
1179 		data = mos7720_port->shadowLCR & ~UART_LCR_SBC;
1180 
1181 	mos7720_port->shadowLCR  = data;
1182 	write_mos_reg(serial, port->port_number, LCR, 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_KERNEL);
1253 		if (urb->transfer_buffer == NULL) {
1254 			dev_err_console(port, "%s no more kernel memory...\n",
1255 				__func__);
1256 			goto exit;
1257 		}
1258 	}
1259 	transfer_size = min(count, URB_TRANSFER_BUFFER_SIZE);
1260 
1261 	memcpy(urb->transfer_buffer, current_position, transfer_size);
1262 	usb_serial_debug_data(&port->dev, __func__, transfer_size,
1263 			      urb->transfer_buffer);
1264 
1265 	/* fill urb with data and submit  */
1266 	usb_fill_bulk_urb(urb, serial->dev,
1267 			  usb_sndbulkpipe(serial->dev,
1268 					port->bulk_out_endpointAddress),
1269 			  urb->transfer_buffer, transfer_size,
1270 			  mos7720_bulk_out_data_callback, mos7720_port);
1271 
1272 	/* send it down the pipe */
1273 	status = usb_submit_urb(urb, GFP_ATOMIC);
1274 	if (status) {
1275 		dev_err_console(port, "%s - usb_submit_urb(write bulk) failed "
1276 			"with status = %d\n", __func__, status);
1277 		bytes_sent = status;
1278 		goto exit;
1279 	}
1280 	bytes_sent = transfer_size;
1281 
1282 exit:
1283 	return bytes_sent;
1284 }
1285 
1286 static void mos7720_throttle(struct tty_struct *tty)
1287 {
1288 	struct usb_serial_port *port = tty->driver_data;
1289 	struct moschip_port *mos7720_port;
1290 	int status;
1291 
1292 	mos7720_port = usb_get_serial_port_data(port);
1293 
1294 	if (mos7720_port == NULL)
1295 		return;
1296 
1297 	if (!mos7720_port->open) {
1298 		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
1299 		return;
1300 	}
1301 
1302 	/* if we are implementing XON/XOFF, send the stop character */
1303 	if (I_IXOFF(tty)) {
1304 		unsigned char stop_char = STOP_CHAR(tty);
1305 		status = mos7720_write(tty, port, &stop_char, 1);
1306 		if (status <= 0)
1307 			return;
1308 	}
1309 
1310 	/* if we are implementing RTS/CTS, toggle that line */
1311 	if (tty->termios.c_cflag & CRTSCTS) {
1312 		mos7720_port->shadowMCR &= ~UART_MCR_RTS;
1313 		write_mos_reg(port->serial, port->port_number, MCR,
1314 			      mos7720_port->shadowMCR);
1315 		if (status != 0)
1316 			return;
1317 	}
1318 }
1319 
1320 static void mos7720_unthrottle(struct tty_struct *tty)
1321 {
1322 	struct usb_serial_port *port = tty->driver_data;
1323 	struct moschip_port *mos7720_port = usb_get_serial_port_data(port);
1324 	int status;
1325 
1326 	if (mos7720_port == NULL)
1327 		return;
1328 
1329 	if (!mos7720_port->open) {
1330 		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
1331 		return;
1332 	}
1333 
1334 	/* if we are implementing XON/XOFF, send the start character */
1335 	if (I_IXOFF(tty)) {
1336 		unsigned char start_char = START_CHAR(tty);
1337 		status = mos7720_write(tty, port, &start_char, 1);
1338 		if (status <= 0)
1339 			return;
1340 	}
1341 
1342 	/* if we are implementing RTS/CTS, toggle that line */
1343 	if (tty->termios.c_cflag & CRTSCTS) {
1344 		mos7720_port->shadowMCR |= UART_MCR_RTS;
1345 		write_mos_reg(port->serial, port->port_number, MCR,
1346 			      mos7720_port->shadowMCR);
1347 		if (status != 0)
1348 			return;
1349 	}
1350 }
1351 
1352 /* FIXME: this function does not work */
1353 static int set_higher_rates(struct moschip_port *mos7720_port,
1354 			    unsigned int baud)
1355 {
1356 	struct usb_serial_port *port;
1357 	struct usb_serial *serial;
1358 	int port_number;
1359 	enum mos_regs sp_reg;
1360 	if (mos7720_port == NULL)
1361 		return -EINVAL;
1362 
1363 	port = mos7720_port->port;
1364 	serial = port->serial;
1365 
1366 	 /***********************************************
1367 	 *      Init Sequence for higher rates
1368 	 ***********************************************/
1369 	dev_dbg(&port->dev, "Sending Setting Commands ..........\n");
1370 	port_number = port->port_number;
1371 
1372 	write_mos_reg(serial, port_number, IER, 0x00);
1373 	write_mos_reg(serial, port_number, FCR, 0x00);
1374 	write_mos_reg(serial, port_number, FCR, 0xcf);
1375 	mos7720_port->shadowMCR = 0x0b;
1376 	write_mos_reg(serial, port_number, MCR, mos7720_port->shadowMCR);
1377 	write_mos_reg(serial, dummy, SP_CONTROL_REG, 0x00);
1378 
1379 	/***********************************************
1380 	 *              Set for higher rates           *
1381 	 ***********************************************/
1382 	/* writing baud rate verbatum into uart clock field clearly not right */
1383 	if (port_number == 0)
1384 		sp_reg = SP1_REG;
1385 	else
1386 		sp_reg = SP2_REG;
1387 	write_mos_reg(serial, dummy, sp_reg, baud * 0x10);
1388 	write_mos_reg(serial, dummy, SP_CONTROL_REG, 0x03);
1389 	mos7720_port->shadowMCR = 0x2b;
1390 	write_mos_reg(serial, port_number, MCR, mos7720_port->shadowMCR);
1391 
1392 	/***********************************************
1393 	 *              Set DLL/DLM
1394 	 ***********************************************/
1395 	mos7720_port->shadowLCR = mos7720_port->shadowLCR | UART_LCR_DLAB;
1396 	write_mos_reg(serial, port_number, LCR, mos7720_port->shadowLCR);
1397 	write_mos_reg(serial, port_number, DLL, 0x01);
1398 	write_mos_reg(serial, port_number, DLM, 0x00);
1399 	mos7720_port->shadowLCR = mos7720_port->shadowLCR & ~UART_LCR_DLAB;
1400 	write_mos_reg(serial, port_number, LCR, mos7720_port->shadowLCR);
1401 
1402 	return 0;
1403 }
1404 
1405 /* baud rate information */
1406 struct divisor_table_entry {
1407 	__u32  baudrate;
1408 	__u16  divisor;
1409 };
1410 
1411 /* Define table of divisors for moschip 7720 hardware	   *
1412  * These assume a 3.6864MHz crystal, the standard /16, and *
1413  * MCR.7 = 0.						   */
1414 static struct divisor_table_entry divisor_table[] = {
1415 	{   50,		2304},
1416 	{   110,	1047},	/* 2094.545455 => 230450   => .0217 % over */
1417 	{   134,	857},	/* 1713.011152 => 230398.5 => .00065% under */
1418 	{   150,	768},
1419 	{   300,	384},
1420 	{   600,	192},
1421 	{   1200,	96},
1422 	{   1800,	64},
1423 	{   2400,	48},
1424 	{   4800,	24},
1425 	{   7200,	16},
1426 	{   9600,	12},
1427 	{   19200,	6},
1428 	{   38400,	3},
1429 	{   57600,	2},
1430 	{   115200,	1},
1431 };
1432 
1433 /*****************************************************************************
1434  * calc_baud_rate_divisor
1435  *	this function calculates the proper baud rate divisor for the specified
1436  *	baud rate.
1437  *****************************************************************************/
1438 static int calc_baud_rate_divisor(struct usb_serial_port *port, int baudrate, int *divisor)
1439 {
1440 	int i;
1441 	__u16 custom;
1442 	__u16 round1;
1443 	__u16 round;
1444 
1445 
1446 	dev_dbg(&port->dev, "%s - %d\n", __func__, baudrate);
1447 
1448 	for (i = 0; i < ARRAY_SIZE(divisor_table); i++) {
1449 		if (divisor_table[i].baudrate == baudrate) {
1450 			*divisor = divisor_table[i].divisor;
1451 			return 0;
1452 		}
1453 	}
1454 
1455 	/* After trying for all the standard baud rates    *
1456 	 * Try calculating the divisor for this baud rate  */
1457 	if (baudrate > 75 &&  baudrate < 230400) {
1458 		/* get the divisor */
1459 		custom = (__u16)(230400L  / baudrate);
1460 
1461 		/* Check for round off */
1462 		round1 = (__u16)(2304000L / baudrate);
1463 		round = (__u16)(round1 - (custom * 10));
1464 		if (round > 4)
1465 			custom++;
1466 		*divisor = custom;
1467 
1468 		dev_dbg(&port->dev, "Baud %d = %d\n", baudrate, custom);
1469 		return 0;
1470 	}
1471 
1472 	dev_dbg(&port->dev, "Baud calculation Failed...\n");
1473 	return -EINVAL;
1474 }
1475 
1476 /*
1477  * send_cmd_write_baud_rate
1478  *	this function sends the proper command to change the baud rate of the
1479  *	specified port.
1480  */
1481 static int send_cmd_write_baud_rate(struct moschip_port *mos7720_port,
1482 				    int baudrate)
1483 {
1484 	struct usb_serial_port *port;
1485 	struct usb_serial *serial;
1486 	int divisor;
1487 	int status;
1488 	unsigned char number;
1489 
1490 	if (mos7720_port == NULL)
1491 		return -1;
1492 
1493 	port = mos7720_port->port;
1494 	serial = port->serial;
1495 
1496 	number = port->port_number;
1497 	dev_dbg(&port->dev, "%s - baud = %d\n", __func__, baudrate);
1498 
1499 	/* Calculate the Divisor */
1500 	status = calc_baud_rate_divisor(port, baudrate, &divisor);
1501 	if (status) {
1502 		dev_err(&port->dev, "%s - bad baud rate\n", __func__);
1503 		return status;
1504 	}
1505 
1506 	/* Enable access to divisor latch */
1507 	mos7720_port->shadowLCR = mos7720_port->shadowLCR | UART_LCR_DLAB;
1508 	write_mos_reg(serial, number, LCR, mos7720_port->shadowLCR);
1509 
1510 	/* Write the divisor */
1511 	write_mos_reg(serial, number, DLL, (__u8)(divisor & 0xff));
1512 	write_mos_reg(serial, number, DLM, (__u8)((divisor & 0xff00) >> 8));
1513 
1514 	/* Disable access to divisor latch */
1515 	mos7720_port->shadowLCR = mos7720_port->shadowLCR & ~UART_LCR_DLAB;
1516 	write_mos_reg(serial, number, LCR, mos7720_port->shadowLCR);
1517 
1518 	return status;
1519 }
1520 
1521 /*
1522  * change_port_settings
1523  *	This routine is called to set the UART on the device to match
1524  *      the specified new settings.
1525  */
1526 static void change_port_settings(struct tty_struct *tty,
1527 				 struct moschip_port *mos7720_port,
1528 				 struct ktermios *old_termios)
1529 {
1530 	struct usb_serial_port *port;
1531 	struct usb_serial *serial;
1532 	int baud;
1533 	unsigned cflag;
1534 	unsigned iflag;
1535 	__u8 mask = 0xff;
1536 	__u8 lData;
1537 	__u8 lParity;
1538 	__u8 lStop;
1539 	int status;
1540 	int port_number;
1541 
1542 	if (mos7720_port == NULL)
1543 		return ;
1544 
1545 	port = mos7720_port->port;
1546 	serial = port->serial;
1547 	port_number = port->port_number;
1548 
1549 	if (!mos7720_port->open) {
1550 		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
1551 		return;
1552 	}
1553 
1554 	lData = UART_LCR_WLEN8;
1555 	lStop = 0x00;	/* 1 stop bit */
1556 	lParity = 0x00;	/* No parity */
1557 
1558 	cflag = tty->termios.c_cflag;
1559 	iflag = tty->termios.c_iflag;
1560 
1561 	/* Change the number of bits */
1562 	switch (cflag & CSIZE) {
1563 	case CS5:
1564 		lData = UART_LCR_WLEN5;
1565 		mask = 0x1f;
1566 		break;
1567 
1568 	case CS6:
1569 		lData = UART_LCR_WLEN6;
1570 		mask = 0x3f;
1571 		break;
1572 
1573 	case CS7:
1574 		lData = UART_LCR_WLEN7;
1575 		mask = 0x7f;
1576 		break;
1577 	default:
1578 	case CS8:
1579 		lData = UART_LCR_WLEN8;
1580 		break;
1581 	}
1582 
1583 	/* Change the Parity bit */
1584 	if (cflag & PARENB) {
1585 		if (cflag & PARODD) {
1586 			lParity = UART_LCR_PARITY;
1587 			dev_dbg(&port->dev, "%s - parity = odd\n", __func__);
1588 		} else {
1589 			lParity = (UART_LCR_EPAR | UART_LCR_PARITY);
1590 			dev_dbg(&port->dev, "%s - parity = even\n", __func__);
1591 		}
1592 
1593 	} else {
1594 		dev_dbg(&port->dev, "%s - parity = none\n", __func__);
1595 	}
1596 
1597 	if (cflag & CMSPAR)
1598 		lParity = lParity | 0x20;
1599 
1600 	/* Change the Stop bit */
1601 	if (cflag & CSTOPB) {
1602 		lStop = UART_LCR_STOP;
1603 		dev_dbg(&port->dev, "%s - stop bits = 2\n", __func__);
1604 	} else {
1605 		lStop = 0x00;
1606 		dev_dbg(&port->dev, "%s - stop bits = 1\n", __func__);
1607 	}
1608 
1609 #define LCR_BITS_MASK		0x03	/* Mask for bits/char field */
1610 #define LCR_STOP_MASK		0x04	/* Mask for stop bits field */
1611 #define LCR_PAR_MASK		0x38	/* Mask for parity field */
1612 
1613 	/* Update the LCR with the correct value */
1614 	mos7720_port->shadowLCR &=
1615 		~(LCR_BITS_MASK | LCR_STOP_MASK | LCR_PAR_MASK);
1616 	mos7720_port->shadowLCR |= (lData | lParity | lStop);
1617 
1618 
1619 	/* Disable Interrupts */
1620 	write_mos_reg(serial, port_number, IER, 0x00);
1621 	write_mos_reg(serial, port_number, FCR, 0x00);
1622 	write_mos_reg(serial, port_number, FCR, 0xcf);
1623 
1624 	/* Send the updated LCR value to the mos7720 */
1625 	write_mos_reg(serial, port_number, LCR, mos7720_port->shadowLCR);
1626 	mos7720_port->shadowMCR = 0x0b;
1627 	write_mos_reg(serial, port_number, MCR, 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, SP_CONTROL_REG, 0x01);
1640 		else
1641 			write_mos_reg(serial, dummy, SP_CONTROL_REG, 0x02);
1642 
1643 	} else
1644 		mos7720_port->shadowMCR &= ~(UART_MCR_XONANY);
1645 
1646 	write_mos_reg(serial, port_number, MCR, mos7720_port->shadowMCR);
1647 
1648 	/* Determine divisor based on baud rate */
1649 	baud = tty_get_baud_rate(tty);
1650 	if (!baud) {
1651 		/* pick a default, any default... */
1652 		dev_dbg(&port->dev, "Picked default baud...\n");
1653 		baud = 9600;
1654 	}
1655 
1656 	if (baud >= 230400) {
1657 		set_higher_rates(mos7720_port, baud);
1658 		/* Enable Interrupts */
1659 		write_mos_reg(serial, port_number, IER, 0x0c);
1660 		return;
1661 	}
1662 
1663 	dev_dbg(&port->dev, "%s - baud rate = %d\n", __func__, baud);
1664 	status = send_cmd_write_baud_rate(mos7720_port, baud);
1665 	/* FIXME: needs to write actual resulting baud back not just
1666 	   blindly do so */
1667 	if (cflag & CBAUD)
1668 		tty_encode_baud_rate(tty, baud, baud);
1669 	/* Enable Interrupts */
1670 	write_mos_reg(serial, port_number, IER, 0x0c);
1671 
1672 	if (port->read_urb->status != -EINPROGRESS) {
1673 		status = usb_submit_urb(port->read_urb, GFP_ATOMIC);
1674 		if (status)
1675 			dev_dbg(&port->dev, "usb_submit_urb(read bulk) failed, status = %d\n", status);
1676 	}
1677 }
1678 
1679 /*
1680  * mos7720_set_termios
1681  *	this function is called by the tty driver when it wants to change the
1682  *	termios structure.
1683  */
1684 static void mos7720_set_termios(struct tty_struct *tty,
1685 		struct usb_serial_port *port, struct ktermios *old_termios)
1686 {
1687 	int status;
1688 	unsigned int cflag;
1689 	struct usb_serial *serial;
1690 	struct moschip_port *mos7720_port;
1691 
1692 	serial = port->serial;
1693 
1694 	mos7720_port = usb_get_serial_port_data(port);
1695 
1696 	if (mos7720_port == NULL)
1697 		return;
1698 
1699 	if (!mos7720_port->open) {
1700 		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
1701 		return;
1702 	}
1703 
1704 	dev_dbg(&port->dev, "setting termios - ASPIRE\n");
1705 
1706 	cflag = tty->termios.c_cflag;
1707 
1708 	dev_dbg(&port->dev, "%s - cflag %08x iflag %08x\n", __func__,
1709 		tty->termios.c_cflag, RELEVANT_IFLAG(tty->termios.c_iflag));
1710 
1711 	dev_dbg(&port->dev, "%s - old cflag %08x old iflag %08x\n", __func__,
1712 		old_termios->c_cflag, RELEVANT_IFLAG(old_termios->c_iflag));
1713 
1714 	/* change the port settings to the new ones specified */
1715 	change_port_settings(tty, mos7720_port, old_termios);
1716 
1717 	if (port->read_urb->status != -EINPROGRESS) {
1718 		status = usb_submit_urb(port->read_urb, GFP_ATOMIC);
1719 		if (status)
1720 			dev_dbg(&port->dev, "usb_submit_urb(read bulk) failed, status = %d\n", status);
1721 	}
1722 }
1723 
1724 /*
1725  * get_lsr_info - get line status register info
1726  *
1727  * Purpose: Let user call ioctl() to get info when the UART physically
1728  * 	    is emptied.  On bus types like RS485, the transmitter must
1729  * 	    release the bus after transmitting. This must be done when
1730  * 	    the transmit shift register is empty, not be done when the
1731  * 	    transmit holding register is empty.  This functionality
1732  * 	    allows an RS485 driver to be written in user space.
1733  */
1734 static int get_lsr_info(struct tty_struct *tty,
1735 		struct moschip_port *mos7720_port, unsigned int __user *value)
1736 {
1737 	struct usb_serial_port *port = tty->driver_data;
1738 	unsigned int result = 0;
1739 	unsigned char data = 0;
1740 	int port_number = port->port_number;
1741 	int count;
1742 
1743 	count = mos7720_chars_in_buffer(tty);
1744 	if (count == 0) {
1745 		read_mos_reg(port->serial, port_number, LSR, &data);
1746 		if ((data & (UART_LSR_TEMT | UART_LSR_THRE))
1747 					== (UART_LSR_TEMT | UART_LSR_THRE)) {
1748 			dev_dbg(&port->dev, "%s -- Empty\n", __func__);
1749 			result = TIOCSER_TEMT;
1750 		}
1751 	}
1752 	if (copy_to_user(value, &result, sizeof(int)))
1753 		return -EFAULT;
1754 	return 0;
1755 }
1756 
1757 static int mos7720_tiocmget(struct tty_struct *tty)
1758 {
1759 	struct usb_serial_port *port = tty->driver_data;
1760 	struct moschip_port *mos7720_port = usb_get_serial_port_data(port);
1761 	unsigned int result = 0;
1762 	unsigned int mcr ;
1763 	unsigned int msr ;
1764 
1765 	mcr = mos7720_port->shadowMCR;
1766 	msr = mos7720_port->shadowMSR;
1767 
1768 	result = ((mcr & UART_MCR_DTR)  ? TIOCM_DTR : 0)   /* 0x002 */
1769 	  | ((mcr & UART_MCR_RTS)   ? TIOCM_RTS : 0)   /* 0x004 */
1770 	  | ((msr & UART_MSR_CTS)   ? TIOCM_CTS : 0)   /* 0x020 */
1771 	  | ((msr & UART_MSR_DCD)   ? TIOCM_CAR : 0)   /* 0x040 */
1772 	  | ((msr & UART_MSR_RI)    ? TIOCM_RI :  0)   /* 0x080 */
1773 	  | ((msr & UART_MSR_DSR)   ? TIOCM_DSR : 0);  /* 0x100 */
1774 
1775 	return result;
1776 }
1777 
1778 static int mos7720_tiocmset(struct tty_struct *tty,
1779 			    unsigned int set, unsigned int clear)
1780 {
1781 	struct usb_serial_port *port = tty->driver_data;
1782 	struct moschip_port *mos7720_port = usb_get_serial_port_data(port);
1783 	unsigned int mcr ;
1784 
1785 	mcr = mos7720_port->shadowMCR;
1786 
1787 	if (set & TIOCM_RTS)
1788 		mcr |= UART_MCR_RTS;
1789 	if (set & TIOCM_DTR)
1790 		mcr |= UART_MCR_DTR;
1791 	if (set & TIOCM_LOOP)
1792 		mcr |= UART_MCR_LOOP;
1793 
1794 	if (clear & TIOCM_RTS)
1795 		mcr &= ~UART_MCR_RTS;
1796 	if (clear & TIOCM_DTR)
1797 		mcr &= ~UART_MCR_DTR;
1798 	if (clear & TIOCM_LOOP)
1799 		mcr &= ~UART_MCR_LOOP;
1800 
1801 	mos7720_port->shadowMCR = mcr;
1802 	write_mos_reg(port->serial, port->port_number, MCR,
1803 		      mos7720_port->shadowMCR);
1804 
1805 	return 0;
1806 }
1807 
1808 static int set_modem_info(struct moschip_port *mos7720_port, unsigned int cmd,
1809 			  unsigned int __user *value)
1810 {
1811 	unsigned int mcr;
1812 	unsigned int arg;
1813 
1814 	struct usb_serial_port *port;
1815 
1816 	if (mos7720_port == NULL)
1817 		return -1;
1818 
1819 	port = (struct usb_serial_port *)mos7720_port->port;
1820 	mcr = mos7720_port->shadowMCR;
1821 
1822 	if (copy_from_user(&arg, value, sizeof(int)))
1823 		return -EFAULT;
1824 
1825 	switch (cmd) {
1826 	case TIOCMBIS:
1827 		if (arg & TIOCM_RTS)
1828 			mcr |= UART_MCR_RTS;
1829 		if (arg & TIOCM_DTR)
1830 			mcr |= UART_MCR_RTS;
1831 		if (arg & TIOCM_LOOP)
1832 			mcr |= UART_MCR_LOOP;
1833 		break;
1834 
1835 	case TIOCMBIC:
1836 		if (arg & TIOCM_RTS)
1837 			mcr &= ~UART_MCR_RTS;
1838 		if (arg & TIOCM_DTR)
1839 			mcr &= ~UART_MCR_RTS;
1840 		if (arg & TIOCM_LOOP)
1841 			mcr &= ~UART_MCR_LOOP;
1842 		break;
1843 
1844 	}
1845 
1846 	mos7720_port->shadowMCR = mcr;
1847 	write_mos_reg(port->serial, port->port_number, MCR,
1848 		      mos7720_port->shadowMCR);
1849 
1850 	return 0;
1851 }
1852 
1853 static int get_serial_info(struct moschip_port *mos7720_port,
1854 			   struct serial_struct __user *retinfo)
1855 {
1856 	struct serial_struct tmp;
1857 
1858 	if (!retinfo)
1859 		return -EFAULT;
1860 
1861 	memset(&tmp, 0, sizeof(tmp));
1862 
1863 	tmp.type		= PORT_16550A;
1864 	tmp.line		= mos7720_port->port->minor;
1865 	tmp.port		= mos7720_port->port->port_number;
1866 	tmp.irq			= 0;
1867 	tmp.flags		= ASYNC_SKIP_TEST | ASYNC_AUTO_IRQ;
1868 	tmp.xmit_fifo_size	= NUM_URBS * URB_TRANSFER_BUFFER_SIZE;
1869 	tmp.baud_base		= 9600;
1870 	tmp.close_delay		= 5*HZ;
1871 	tmp.closing_wait	= 30*HZ;
1872 
1873 	if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
1874 		return -EFAULT;
1875 	return 0;
1876 }
1877 
1878 static int mos7720_ioctl(struct tty_struct *tty,
1879 			 unsigned int cmd, unsigned long arg)
1880 {
1881 	struct usb_serial_port *port = tty->driver_data;
1882 	struct moschip_port *mos7720_port;
1883 
1884 	mos7720_port = usb_get_serial_port_data(port);
1885 	if (mos7720_port == NULL)
1886 		return -ENODEV;
1887 
1888 	dev_dbg(&port->dev, "%s - cmd = 0x%x", __func__, cmd);
1889 
1890 	switch (cmd) {
1891 	case TIOCSERGETLSR:
1892 		dev_dbg(&port->dev, "%s TIOCSERGETLSR\n", __func__);
1893 		return get_lsr_info(tty, mos7720_port,
1894 					(unsigned int __user *)arg);
1895 
1896 	/* FIXME: These should be using the mode methods */
1897 	case TIOCMBIS:
1898 	case TIOCMBIC:
1899 		dev_dbg(&port->dev, "%s TIOCMSET/TIOCMBIC/TIOCMSET\n", __func__);
1900 		return set_modem_info(mos7720_port, cmd,
1901 				      (unsigned int __user *)arg);
1902 
1903 	case TIOCGSERIAL:
1904 		dev_dbg(&port->dev, "%s TIOCGSERIAL\n", __func__);
1905 		return get_serial_info(mos7720_port,
1906 				       (struct serial_struct __user *)arg);
1907 	}
1908 
1909 	return -ENOIOCTLCMD;
1910 }
1911 
1912 static int mos7720_startup(struct usb_serial *serial)
1913 {
1914 	struct usb_device *dev;
1915 	char data;
1916 	u16 product;
1917 	int ret_val;
1918 
1919 	product = le16_to_cpu(serial->dev->descriptor.idProduct);
1920 	dev = serial->dev;
1921 
1922 	/*
1923 	 * The 7715 uses the first bulk in/out endpoint pair for the parallel
1924 	 * port, and the second for the serial port.  Because the usbserial core
1925 	 * assumes both pairs are serial ports, we must engage in a bit of
1926 	 * subterfuge and swap the pointers for ports 0 and 1 in order to make
1927 	 * port 0 point to the serial port.  However, both moschip devices use a
1928 	 * single interrupt-in endpoint for both ports (as mentioned a little
1929 	 * further down), and this endpoint was assigned to port 0.  So after
1930 	 * the swap, we must copy the interrupt endpoint elements from port 1
1931 	 * (as newly assigned) to port 0, and null out port 1 pointers.
1932 	 */
1933 	if (product == MOSCHIP_DEVICE_ID_7715) {
1934 		struct usb_serial_port *tmp = serial->port[0];
1935 		serial->port[0] = serial->port[1];
1936 		serial->port[1] = tmp;
1937 		serial->port[0]->interrupt_in_urb = tmp->interrupt_in_urb;
1938 		serial->port[0]->interrupt_in_buffer = tmp->interrupt_in_buffer;
1939 		serial->port[0]->interrupt_in_endpointAddress =
1940 			tmp->interrupt_in_endpointAddress;
1941 		serial->port[1]->interrupt_in_urb = NULL;
1942 		serial->port[1]->interrupt_in_buffer = NULL;
1943 	}
1944 
1945 	/* setting configuration feature to one */
1946 	usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
1947 			(__u8)0x03, 0x00, 0x01, 0x00, NULL, 0x00, 5000);
1948 
1949 	/* start the interrupt urb */
1950 	ret_val = usb_submit_urb(serial->port[0]->interrupt_in_urb, GFP_KERNEL);
1951 	if (ret_val)
1952 		dev_err(&dev->dev,
1953 			"%s - Error %d submitting control urb\n",
1954 			__func__, ret_val);
1955 
1956 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
1957 	if (product == MOSCHIP_DEVICE_ID_7715) {
1958 		ret_val = mos7715_parport_init(serial);
1959 		if (ret_val < 0)
1960 			return ret_val;
1961 	}
1962 #endif
1963 	/* LSR For Port 1 */
1964 	read_mos_reg(serial, 0, LSR, &data);
1965 	dev_dbg(&dev->dev, "LSR:%x\n", data);
1966 
1967 	return 0;
1968 }
1969 
1970 static void mos7720_release(struct usb_serial *serial)
1971 {
1972 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
1973 	/* close the parallel port */
1974 
1975 	if (le16_to_cpu(serial->dev->descriptor.idProduct)
1976 	    == MOSCHIP_DEVICE_ID_7715) {
1977 		struct urbtracker *urbtrack;
1978 		unsigned long flags;
1979 		struct mos7715_parport *mos_parport =
1980 			usb_get_serial_data(serial);
1981 
1982 		/* prevent NULL ptr dereference in port callbacks */
1983 		spin_lock(&release_lock);
1984 		mos_parport->pp->private_data = NULL;
1985 		spin_unlock(&release_lock);
1986 
1987 		/* wait for synchronous usb calls to return */
1988 		if (mos_parport->msg_pending)
1989 			wait_for_completion_timeout(&mos_parport->syncmsg_compl,
1990 					    msecs_to_jiffies(MOS_WDR_TIMEOUT));
1991 
1992 		parport_remove_port(mos_parport->pp);
1993 		usb_set_serial_data(serial, NULL);
1994 		mos_parport->serial = NULL;
1995 
1996 		/* if tasklet currently scheduled, wait for it to complete */
1997 		tasklet_kill(&mos_parport->urb_tasklet);
1998 
1999 		/* unlink any urbs sent by the tasklet  */
2000 		spin_lock_irqsave(&mos_parport->listlock, flags);
2001 		list_for_each_entry(urbtrack,
2002 				    &mos_parport->active_urbs,
2003 				    urblist_entry)
2004 			usb_unlink_urb(urbtrack->urb);
2005 		spin_unlock_irqrestore(&mos_parport->listlock, flags);
2006 
2007 		kref_put(&mos_parport->ref_count, destroy_mos_parport);
2008 	}
2009 #endif
2010 }
2011 
2012 static int mos7720_port_probe(struct usb_serial_port *port)
2013 {
2014 	struct moschip_port *mos7720_port;
2015 
2016 	mos7720_port = kzalloc(sizeof(*mos7720_port), GFP_KERNEL);
2017 	if (!mos7720_port)
2018 		return -ENOMEM;
2019 
2020 	/* Initialize all port interrupt end point to port 0 int endpoint.
2021 	 * Our device has only one interrupt endpoint common to all ports.
2022 	 */
2023 	port->interrupt_in_endpointAddress =
2024 		port->serial->port[0]->interrupt_in_endpointAddress;
2025 	mos7720_port->port = port;
2026 
2027 	usb_set_serial_port_data(port, mos7720_port);
2028 
2029 	return 0;
2030 }
2031 
2032 static int mos7720_port_remove(struct usb_serial_port *port)
2033 {
2034 	struct moschip_port *mos7720_port;
2035 
2036 	mos7720_port = usb_get_serial_port_data(port);
2037 	kfree(mos7720_port);
2038 
2039 	return 0;
2040 }
2041 
2042 static struct usb_serial_driver moschip7720_2port_driver = {
2043 	.driver = {
2044 		.owner =	THIS_MODULE,
2045 		.name =		"moschip7720",
2046 	},
2047 	.description		= "Moschip 2 port adapter",
2048 	.id_table		= id_table,
2049 	.calc_num_ports		= mos77xx_calc_num_ports,
2050 	.open			= mos7720_open,
2051 	.close			= mos7720_close,
2052 	.throttle		= mos7720_throttle,
2053 	.unthrottle		= mos7720_unthrottle,
2054 	.probe			= mos77xx_probe,
2055 	.attach			= mos7720_startup,
2056 	.release		= mos7720_release,
2057 	.port_probe		= mos7720_port_probe,
2058 	.port_remove		= mos7720_port_remove,
2059 	.ioctl			= mos7720_ioctl,
2060 	.tiocmget		= mos7720_tiocmget,
2061 	.tiocmset		= mos7720_tiocmset,
2062 	.set_termios		= mos7720_set_termios,
2063 	.write			= mos7720_write,
2064 	.write_room		= mos7720_write_room,
2065 	.chars_in_buffer	= mos7720_chars_in_buffer,
2066 	.break_ctl		= mos7720_break,
2067 	.read_bulk_callback	= mos7720_bulk_in_callback,
2068 	.read_int_callback	= NULL  /* dynamically assigned in probe() */
2069 };
2070 
2071 static struct usb_serial_driver * const serial_drivers[] = {
2072 	&moschip7720_2port_driver, NULL
2073 };
2074 
2075 module_usb_serial_driver(serial_drivers, id_table);
2076 
2077 MODULE_AUTHOR(DRIVER_AUTHOR);
2078 MODULE_DESCRIPTION(DRIVER_DESC);
2079 MODULE_LICENSE("GPL");
2080