xref: /openbmc/linux/drivers/usb/serial/mos7720.c (revision 4cff79e9)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * mos7720.c
4  *   Controls the Moschip 7720 usb to dual port serial converter
5  *
6  * Copyright 2006 Moschip Semiconductor Tech. Ltd.
7  *
8  * Developed by:
9  * 	Vijaya Kumar <vijaykumar.gn@gmail.com>
10  *	Ajay Kumar <naanuajay@yahoo.com>
11  *	Gurudeva <ngurudeva@yahoo.com>
12  *
13  * Cleaned up from the original by:
14  *	Greg Kroah-Hartman <gregkh@suse.de>
15  *
16  * Originally based on drivers/usb/serial/io_edgeport.c which is:
17  *	Copyright (C) 2000 Inside Out Networks, All rights reserved.
18  *	Copyright (C) 2001-2002 Greg Kroah-Hartman <greg@kroah.com>
19  */
20 #include <linux/kernel.h>
21 #include <linux/errno.h>
22 #include <linux/slab.h>
23 #include <linux/tty.h>
24 #include <linux/tty_driver.h>
25 #include <linux/tty_flip.h>
26 #include <linux/module.h>
27 #include <linux/spinlock.h>
28 #include <linux/serial.h>
29 #include <linux/serial_reg.h>
30 #include <linux/usb.h>
31 #include <linux/usb/serial.h>
32 #include <linux/uaccess.h>
33 #include <linux/parport.h>
34 
35 #define DRIVER_AUTHOR "Aspire Communications pvt Ltd."
36 #define DRIVER_DESC "Moschip USB Serial Driver"
37 
38 /* default urb timeout */
39 #define MOS_WDR_TIMEOUT	5000
40 
41 #define MOS_MAX_PORT	0x02
42 #define MOS_WRITE	0x0E
43 #define MOS_READ	0x0D
44 
45 /* Interrupt Routines Defines	*/
46 #define SERIAL_IIR_RLS	0x06
47 #define SERIAL_IIR_RDA	0x04
48 #define SERIAL_IIR_CTI	0x0c
49 #define SERIAL_IIR_THR	0x02
50 #define SERIAL_IIR_MS	0x00
51 
52 #define NUM_URBS			16	/* URB Count */
53 #define URB_TRANSFER_BUFFER_SIZE	32	/* URB Size */
54 
55 /* This structure holds all of the local serial port information */
56 struct moschip_port {
57 	__u8	shadowLCR;		/* last LCR value received */
58 	__u8	shadowMCR;		/* last MCR value received */
59 	__u8	shadowMSR;		/* last MSR value received */
60 	char			open;
61 	struct usb_serial_port	*port;	/* loop back to the owner */
62 	struct urb		*write_urb_pool[NUM_URBS];
63 };
64 
65 #define USB_VENDOR_ID_MOSCHIP		0x9710
66 #define MOSCHIP_DEVICE_ID_7720		0x7720
67 #define MOSCHIP_DEVICE_ID_7715		0x7715
68 
69 static const struct usb_device_id id_table[] = {
70 	{ USB_DEVICE(USB_VENDOR_ID_MOSCHIP, MOSCHIP_DEVICE_ID_7720) },
71 	{ USB_DEVICE(USB_VENDOR_ID_MOSCHIP, MOSCHIP_DEVICE_ID_7715) },
72 	{ } /* terminating entry */
73 };
74 MODULE_DEVICE_TABLE(usb, id_table);
75 
76 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
77 
78 /* initial values for parport regs */
79 #define DCR_INIT_VAL       0x0c	/* SLCTIN, nINIT */
80 #define ECR_INIT_VAL       0x00	/* SPP mode */
81 
82 struct urbtracker {
83 	struct mos7715_parport  *mos_parport;
84 	struct list_head        urblist_entry;
85 	struct kref             ref_count;
86 	struct urb              *urb;
87 	struct usb_ctrlrequest	*setup;
88 };
89 
90 enum mos7715_pp_modes {
91 	SPP = 0<<5,
92 	PS2 = 1<<5,      /* moschip calls this 'NIBBLE' mode */
93 	PPF = 2<<5,	 /* moschip calls this 'CB-FIFO mode */
94 };
95 
96 struct mos7715_parport {
97 	struct parport          *pp;	       /* back to containing struct */
98 	struct kref             ref_count;     /* to instance of this struct */
99 	struct list_head        deferred_urbs; /* list deferred async urbs */
100 	struct list_head        active_urbs;   /* list async urbs in flight */
101 	spinlock_t              listlock;      /* protects list access */
102 	bool                    msg_pending;   /* usb sync call pending */
103 	struct completion       syncmsg_compl; /* usb sync call completed */
104 	struct tasklet_struct   urb_tasklet;   /* for sending deferred urbs */
105 	struct usb_serial       *serial;       /* back to containing struct */
106 	__u8	                shadowECR;     /* parallel port regs... */
107 	__u8	                shadowDCR;
108 	atomic_t                shadowDSR;     /* updated in int-in callback */
109 };
110 
111 /* lock guards against dereferencing NULL ptr in parport ops callbacks */
112 static DEFINE_SPINLOCK(release_lock);
113 
114 #endif	/* CONFIG_USB_SERIAL_MOS7715_PARPORT */
115 
116 static const unsigned int dummy; /* for clarity in register access fns */
117 
118 enum mos_regs {
119 	MOS7720_THR,		  /* serial port regs */
120 	MOS7720_RHR,
121 	MOS7720_IER,
122 	MOS7720_FCR,
123 	MOS7720_ISR,
124 	MOS7720_LCR,
125 	MOS7720_MCR,
126 	MOS7720_LSR,
127 	MOS7720_MSR,
128 	MOS7720_SPR,
129 	MOS7720_DLL,
130 	MOS7720_DLM,
131 	MOS7720_DPR,		  /* parallel port regs */
132 	MOS7720_DSR,
133 	MOS7720_DCR,
134 	MOS7720_ECR,
135 	MOS7720_SP1_REG,	  /* device control regs */
136 	MOS7720_SP2_REG,	  /* serial port 2 (7720 only) */
137 	MOS7720_PP_REG,
138 	MOS7720_SP_CONTROL_REG,
139 };
140 
141 /*
142  * Return the correct value for the Windex field of the setup packet
143  * for a control endpoint message.  See the 7715 datasheet.
144  */
145 static inline __u16 get_reg_index(enum mos_regs reg)
146 {
147 	static const __u16 mos7715_index_lookup_table[] = {
148 		0x00,		/* MOS7720_THR */
149 		0x00,		/* MOS7720_RHR */
150 		0x01,		/* MOS7720_IER */
151 		0x02,		/* MOS7720_FCR */
152 		0x02,		/* MOS7720_ISR */
153 		0x03,		/* MOS7720_LCR */
154 		0x04,		/* MOS7720_MCR */
155 		0x05,		/* MOS7720_LSR */
156 		0x06,		/* MOS7720_MSR */
157 		0x07,		/* MOS7720_SPR */
158 		0x00,		/* MOS7720_DLL */
159 		0x01,		/* MOS7720_DLM */
160 		0x00,		/* MOS7720_DPR */
161 		0x01,		/* MOS7720_DSR */
162 		0x02,		/* MOS7720_DCR */
163 		0x0a,		/* MOS7720_ECR */
164 		0x01,		/* MOS7720_SP1_REG */
165 		0x02,		/* MOS7720_SP2_REG (7720 only) */
166 		0x04,		/* MOS7720_PP_REG (7715 only) */
167 		0x08,		/* MOS7720_SP_CONTROL_REG */
168 	};
169 	return mos7715_index_lookup_table[reg];
170 }
171 
172 /*
173  * Return the correct value for the upper byte of the Wvalue field of
174  * the setup packet for a control endpoint message.
175  */
176 static inline __u16 get_reg_value(enum mos_regs reg,
177 				  unsigned int serial_portnum)
178 {
179 	if (reg >= MOS7720_SP1_REG)	/* control reg */
180 		return 0x0000;
181 
182 	else if (reg >= MOS7720_DPR)	/* parallel port reg (7715 only) */
183 		return 0x0100;
184 
185 	else			      /* serial port reg */
186 		return (serial_portnum + 2) << 8;
187 }
188 
189 /*
190  * Write data byte to the specified device register.  The data is embedded in
191  * the value field of the setup packet. serial_portnum is ignored for registers
192  * not specific to a particular serial port.
193  */
194 static int write_mos_reg(struct usb_serial *serial, unsigned int serial_portnum,
195 			 enum mos_regs reg, __u8 data)
196 {
197 	struct usb_device *usbdev = serial->dev;
198 	unsigned int pipe = usb_sndctrlpipe(usbdev, 0);
199 	__u8 request = (__u8)0x0e;
200 	__u8 requesttype = (__u8)0x40;
201 	__u16 index = get_reg_index(reg);
202 	__u16 value = get_reg_value(reg, serial_portnum) + data;
203 	int status = usb_control_msg(usbdev, pipe, request, requesttype, value,
204 				     index, NULL, 0, MOS_WDR_TIMEOUT);
205 	if (status < 0)
206 		dev_err(&usbdev->dev,
207 			"mos7720: usb_control_msg() failed: %d\n", status);
208 	return status;
209 }
210 
211 /*
212  * Read data byte from the specified device register.  The data returned by the
213  * device is embedded in the value field of the setup packet.  serial_portnum is
214  * ignored for registers that are not specific to a particular serial port.
215  */
216 static int read_mos_reg(struct usb_serial *serial, unsigned int serial_portnum,
217 			enum mos_regs reg, __u8 *data)
218 {
219 	struct usb_device *usbdev = serial->dev;
220 	unsigned int pipe = usb_rcvctrlpipe(usbdev, 0);
221 	__u8 request = (__u8)0x0d;
222 	__u8 requesttype = (__u8)0xc0;
223 	__u16 index = get_reg_index(reg);
224 	__u16 value = get_reg_value(reg, serial_portnum);
225 	u8 *buf;
226 	int status;
227 
228 	buf = kmalloc(1, GFP_KERNEL);
229 	if (!buf)
230 		return -ENOMEM;
231 
232 	status = usb_control_msg(usbdev, pipe, request, requesttype, value,
233 				     index, buf, 1, MOS_WDR_TIMEOUT);
234 	if (status == 1) {
235 		*data = *buf;
236 	} else {
237 		dev_err(&usbdev->dev,
238 			"mos7720: usb_control_msg() failed: %d\n", status);
239 		if (status >= 0)
240 			status = -EIO;
241 		*data = 0;
242 	}
243 
244 	kfree(buf);
245 
246 	return status;
247 }
248 
249 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
250 
251 static inline int mos7715_change_mode(struct mos7715_parport *mos_parport,
252 				      enum mos7715_pp_modes mode)
253 {
254 	mos_parport->shadowECR = mode;
255 	write_mos_reg(mos_parport->serial, dummy, MOS7720_ECR,
256 		      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)
366 		return -ENOMEM;
367 
368 	kref_get(&mos_parport->ref_count);
369 	urbtrack->mos_parport = mos_parport;
370 	urbtrack->urb = usb_alloc_urb(0, GFP_ATOMIC);
371 	if (!urbtrack->urb) {
372 		kfree(urbtrack);
373 		return -ENOMEM;
374 	}
375 	urbtrack->setup = kmalloc(sizeof(*urbtrack->setup), GFP_ATOMIC);
376 	if (!urbtrack->setup) {
377 		usb_free_urb(urbtrack->urb);
378 		kfree(urbtrack);
379 		return -ENOMEM;
380 	}
381 	urbtrack->setup->bRequestType = (__u8)0x40;
382 	urbtrack->setup->bRequest = (__u8)0x0e;
383 	urbtrack->setup->wValue = cpu_to_le16(get_reg_value(reg, dummy));
384 	urbtrack->setup->wIndex = cpu_to_le16(get_reg_index(reg));
385 	urbtrack->setup->wLength = 0;
386 	usb_fill_control_urb(urbtrack->urb, usbdev,
387 			     usb_sndctrlpipe(usbdev, 0),
388 			     (unsigned char *)urbtrack->setup,
389 			     NULL, 0, async_complete, urbtrack);
390 	kref_init(&urbtrack->ref_count);
391 	INIT_LIST_HEAD(&urbtrack->urblist_entry);
392 
393 	/*
394 	 * get the disconnect mutex, or add tracker to the deferred_urbs list
395 	 * and schedule a tasklet to try again later
396 	 */
397 	if (!mutex_trylock(&serial->disc_mutex)) {
398 		spin_lock_irqsave(&mos_parport->listlock, flags);
399 		list_add_tail(&urbtrack->urblist_entry,
400 			      &mos_parport->deferred_urbs);
401 		spin_unlock_irqrestore(&mos_parport->listlock, flags);
402 		tasklet_schedule(&mos_parport->urb_tasklet);
403 		dev_dbg(&usbdev->dev, "tasklet scheduled\n");
404 		return 0;
405 	}
406 
407 	/* bail if device disconnected */
408 	if (serial->disconnected) {
409 		kref_put(&urbtrack->ref_count, destroy_urbtracker);
410 		mutex_unlock(&serial->disc_mutex);
411 		return -ENODEV;
412 	}
413 
414 	/* add the tracker to the active_urbs list and submit */
415 	spin_lock_irqsave(&mos_parport->listlock, flags);
416 	list_add_tail(&urbtrack->urblist_entry, &mos_parport->active_urbs);
417 	spin_unlock_irqrestore(&mos_parport->listlock, flags);
418 	ret_val = usb_submit_urb(urbtrack->urb, GFP_ATOMIC);
419 	mutex_unlock(&serial->disc_mutex);
420 	if (ret_val) {
421 		dev_err(&usbdev->dev,
422 			"%s: submit_urb() failed: %d\n", __func__, ret_val);
423 		spin_lock_irqsave(&mos_parport->listlock, flags);
424 		list_del(&urbtrack->urblist_entry);
425 		spin_unlock_irqrestore(&mos_parport->listlock, flags);
426 		kref_put(&urbtrack->ref_count, destroy_urbtracker);
427 		return ret_val;
428 	}
429 	return 0;
430 }
431 
432 /*
433  * This is the the common top part of all parallel port callback operations that
434  * send synchronous messages to the device.  This implements convoluted locking
435  * that avoids two scenarios: (1) a port operation is called after usbserial
436  * has called our release function, at which point struct mos7715_parport has
437  * been destroyed, and (2) the device has been disconnected, but usbserial has
438  * not called the release function yet because someone has a serial port open.
439  * The shared release_lock prevents the first, and the mutex and disconnected
440  * flag maintained by usbserial covers the second.  We also use the msg_pending
441  * flag to ensure that all synchronous usb message calls have completed before
442  * our release function can return.
443  */
444 static int parport_prologue(struct parport *pp)
445 {
446 	struct mos7715_parport *mos_parport;
447 
448 	spin_lock(&release_lock);
449 	mos_parport = pp->private_data;
450 	if (unlikely(mos_parport == NULL)) {
451 		/* release fn called, port struct destroyed */
452 		spin_unlock(&release_lock);
453 		return -1;
454 	}
455 	mos_parport->msg_pending = true;   /* synch usb call pending */
456 	reinit_completion(&mos_parport->syncmsg_compl);
457 	spin_unlock(&release_lock);
458 
459 	mutex_lock(&mos_parport->serial->disc_mutex);
460 	if (mos_parport->serial->disconnected) {
461 		/* device disconnected */
462 		mutex_unlock(&mos_parport->serial->disc_mutex);
463 		mos_parport->msg_pending = false;
464 		complete(&mos_parport->syncmsg_compl);
465 		return -1;
466 	}
467 
468 	return 0;
469 }
470 
471 /*
472  * This is the common bottom part of all parallel port functions that send
473  * synchronous messages to the device.
474  */
475 static inline void parport_epilogue(struct parport *pp)
476 {
477 	struct mos7715_parport *mos_parport = pp->private_data;
478 	mutex_unlock(&mos_parport->serial->disc_mutex);
479 	mos_parport->msg_pending = false;
480 	complete(&mos_parport->syncmsg_compl);
481 }
482 
483 static void parport_mos7715_write_data(struct parport *pp, unsigned char d)
484 {
485 	struct mos7715_parport *mos_parport = pp->private_data;
486 
487 	if (parport_prologue(pp) < 0)
488 		return;
489 	mos7715_change_mode(mos_parport, SPP);
490 	write_mos_reg(mos_parport->serial, dummy, MOS7720_DPR, (__u8)d);
491 	parport_epilogue(pp);
492 }
493 
494 static unsigned char parport_mos7715_read_data(struct parport *pp)
495 {
496 	struct mos7715_parport *mos_parport = pp->private_data;
497 	unsigned char d;
498 
499 	if (parport_prologue(pp) < 0)
500 		return 0;
501 	read_mos_reg(mos_parport->serial, dummy, MOS7720_DPR, &d);
502 	parport_epilogue(pp);
503 	return d;
504 }
505 
506 static void parport_mos7715_write_control(struct parport *pp, unsigned char d)
507 {
508 	struct mos7715_parport *mos_parport = pp->private_data;
509 	__u8 data;
510 
511 	if (parport_prologue(pp) < 0)
512 		return;
513 	data = ((__u8)d & 0x0f) | (mos_parport->shadowDCR & 0xf0);
514 	write_mos_reg(mos_parport->serial, dummy, MOS7720_DCR, data);
515 	mos_parport->shadowDCR = data;
516 	parport_epilogue(pp);
517 }
518 
519 static unsigned char parport_mos7715_read_control(struct parport *pp)
520 {
521 	struct mos7715_parport *mos_parport;
522 	__u8 dcr;
523 
524 	spin_lock(&release_lock);
525 	mos_parport = pp->private_data;
526 	if (unlikely(mos_parport == NULL)) {
527 		spin_unlock(&release_lock);
528 		return 0;
529 	}
530 	dcr = mos_parport->shadowDCR & 0x0f;
531 	spin_unlock(&release_lock);
532 	return dcr;
533 }
534 
535 static unsigned char parport_mos7715_frob_control(struct parport *pp,
536 						  unsigned char mask,
537 						  unsigned char val)
538 {
539 	struct mos7715_parport *mos_parport = pp->private_data;
540 	__u8 dcr;
541 
542 	mask &= 0x0f;
543 	val &= 0x0f;
544 	if (parport_prologue(pp) < 0)
545 		return 0;
546 	mos_parport->shadowDCR = (mos_parport->shadowDCR & (~mask)) ^ val;
547 	write_mos_reg(mos_parport->serial, dummy, MOS7720_DCR,
548 		      mos_parport->shadowDCR);
549 	dcr = mos_parport->shadowDCR & 0x0f;
550 	parport_epilogue(pp);
551 	return dcr;
552 }
553 
554 static unsigned char parport_mos7715_read_status(struct parport *pp)
555 {
556 	unsigned char status;
557 	struct mos7715_parport *mos_parport;
558 
559 	spin_lock(&release_lock);
560 	mos_parport = pp->private_data;
561 	if (unlikely(mos_parport == NULL)) {	/* release called */
562 		spin_unlock(&release_lock);
563 		return 0;
564 	}
565 	status = atomic_read(&mos_parport->shadowDSR) & 0xf8;
566 	spin_unlock(&release_lock);
567 	return status;
568 }
569 
570 static void parport_mos7715_enable_irq(struct parport *pp)
571 {
572 }
573 
574 static void parport_mos7715_disable_irq(struct parport *pp)
575 {
576 }
577 
578 static void parport_mos7715_data_forward(struct parport *pp)
579 {
580 	struct mos7715_parport *mos_parport = pp->private_data;
581 
582 	if (parport_prologue(pp) < 0)
583 		return;
584 	mos7715_change_mode(mos_parport, PS2);
585 	mos_parport->shadowDCR &=  ~0x20;
586 	write_mos_reg(mos_parport->serial, dummy, MOS7720_DCR,
587 		      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, MOS7720_DCR,
600 		      mos_parport->shadowDCR);
601 	parport_epilogue(pp);
602 }
603 
604 static void parport_mos7715_init_state(struct pardevice *dev,
605 				       struct parport_state *s)
606 {
607 	s->u.pc.ctr = DCR_INIT_VAL;
608 	s->u.pc.ecr = ECR_INIT_VAL;
609 }
610 
611 /* N.B. Parport core code requires that this function not block */
612 static void parport_mos7715_save_state(struct parport *pp,
613 				       struct parport_state *s)
614 {
615 	struct mos7715_parport *mos_parport;
616 
617 	spin_lock(&release_lock);
618 	mos_parport = pp->private_data;
619 	if (unlikely(mos_parport == NULL)) {	/* release called */
620 		spin_unlock(&release_lock);
621 		return;
622 	}
623 	s->u.pc.ctr = mos_parport->shadowDCR;
624 	s->u.pc.ecr = mos_parport->shadowECR;
625 	spin_unlock(&release_lock);
626 }
627 
628 /* N.B. Parport core code requires that this function not block */
629 static void parport_mos7715_restore_state(struct parport *pp,
630 					  struct parport_state *s)
631 {
632 	struct mos7715_parport *mos_parport;
633 
634 	spin_lock(&release_lock);
635 	mos_parport = pp->private_data;
636 	if (unlikely(mos_parport == NULL)) {	/* release called */
637 		spin_unlock(&release_lock);
638 		return;
639 	}
640 	write_parport_reg_nonblock(mos_parport, MOS7720_DCR,
641 				   mos_parport->shadowDCR);
642 	write_parport_reg_nonblock(mos_parport, MOS7720_ECR,
643 				   mos_parport->shadowECR);
644 	spin_unlock(&release_lock);
645 }
646 
647 static size_t parport_mos7715_write_compat(struct parport *pp,
648 					   const void *buffer,
649 					   size_t len, int flags)
650 {
651 	int retval;
652 	struct mos7715_parport *mos_parport = pp->private_data;
653 	int actual_len;
654 
655 	if (parport_prologue(pp) < 0)
656 		return 0;
657 	mos7715_change_mode(mos_parport, PPF);
658 	retval = usb_bulk_msg(mos_parport->serial->dev,
659 			      usb_sndbulkpipe(mos_parport->serial->dev, 2),
660 			      (void *)buffer, len, &actual_len,
661 			      MOS_WDR_TIMEOUT);
662 	parport_epilogue(pp);
663 	if (retval) {
664 		dev_err(&mos_parport->serial->dev->dev,
665 			"mos7720: usb_bulk_msg() failed: %d\n", retval);
666 		return 0;
667 	}
668 	return actual_len;
669 }
670 
671 static struct parport_operations parport_mos7715_ops = {
672 	.owner =		THIS_MODULE,
673 	.write_data =		parport_mos7715_write_data,
674 	.read_data =		parport_mos7715_read_data,
675 
676 	.write_control =	parport_mos7715_write_control,
677 	.read_control =		parport_mos7715_read_control,
678 	.frob_control =		parport_mos7715_frob_control,
679 
680 	.read_status =		parport_mos7715_read_status,
681 
682 	.enable_irq =		parport_mos7715_enable_irq,
683 	.disable_irq =		parport_mos7715_disable_irq,
684 
685 	.data_forward =		parport_mos7715_data_forward,
686 	.data_reverse =		parport_mos7715_data_reverse,
687 
688 	.init_state =		parport_mos7715_init_state,
689 	.save_state =		parport_mos7715_save_state,
690 	.restore_state =	parport_mos7715_restore_state,
691 
692 	.compat_write_data =	parport_mos7715_write_compat,
693 
694 	.nibble_read_data =	parport_ieee1284_read_nibble,
695 	.byte_read_data =	parport_ieee1284_read_byte,
696 };
697 
698 /*
699  * Allocate and initialize parallel port control struct, initialize
700  * the parallel port hardware device, and register with the parport subsystem.
701  */
702 static int mos7715_parport_init(struct usb_serial *serial)
703 {
704 	struct mos7715_parport *mos_parport;
705 
706 	/* allocate and initialize parallel port control struct */
707 	mos_parport = kzalloc(sizeof(struct mos7715_parport), GFP_KERNEL);
708 	if (!mos_parport)
709 		return -ENOMEM;
710 
711 	mos_parport->msg_pending = false;
712 	kref_init(&mos_parport->ref_count);
713 	spin_lock_init(&mos_parport->listlock);
714 	INIT_LIST_HEAD(&mos_parport->active_urbs);
715 	INIT_LIST_HEAD(&mos_parport->deferred_urbs);
716 	usb_set_serial_data(serial, mos_parport); /* hijack private pointer */
717 	mos_parport->serial = serial;
718 	tasklet_init(&mos_parport->urb_tasklet, send_deferred_urbs,
719 		     (unsigned long) mos_parport);
720 	init_completion(&mos_parport->syncmsg_compl);
721 
722 	/* cycle parallel port reset bit */
723 	write_mos_reg(mos_parport->serial, dummy, MOS7720_PP_REG, (__u8)0x80);
724 	write_mos_reg(mos_parport->serial, dummy, MOS7720_PP_REG, (__u8)0x00);
725 
726 	/* initialize device registers */
727 	mos_parport->shadowDCR = DCR_INIT_VAL;
728 	write_mos_reg(mos_parport->serial, dummy, MOS7720_DCR,
729 		      mos_parport->shadowDCR);
730 	mos_parport->shadowECR = ECR_INIT_VAL;
731 	write_mos_reg(mos_parport->serial, dummy, MOS7720_ECR,
732 		      mos_parport->shadowECR);
733 
734 	/* register with parport core */
735 	mos_parport->pp = parport_register_port(0, PARPORT_IRQ_NONE,
736 						PARPORT_DMA_NONE,
737 						&parport_mos7715_ops);
738 	if (mos_parport->pp == NULL) {
739 		dev_err(&serial->interface->dev,
740 			"Could not register parport\n");
741 		kref_put(&mos_parport->ref_count, destroy_mos_parport);
742 		return -EIO;
743 	}
744 	mos_parport->pp->private_data = mos_parport;
745 	mos_parport->pp->modes = PARPORT_MODE_COMPAT | PARPORT_MODE_PCSPP;
746 	mos_parport->pp->dev = &serial->interface->dev;
747 	parport_announce_port(mos_parport->pp);
748 
749 	return 0;
750 }
751 #endif	/* CONFIG_USB_SERIAL_MOS7715_PARPORT */
752 
753 /*
754  * mos7720_interrupt_callback
755  *	this is the callback function for when we have received data on the
756  *	interrupt endpoint.
757  */
758 static void mos7720_interrupt_callback(struct urb *urb)
759 {
760 	int result;
761 	int length;
762 	int status = urb->status;
763 	struct device *dev = &urb->dev->dev;
764 	__u8 *data;
765 	__u8 sp1;
766 	__u8 sp2;
767 
768 	switch (status) {
769 	case 0:
770 		/* success */
771 		break;
772 	case -ECONNRESET:
773 	case -ENOENT:
774 	case -ESHUTDOWN:
775 		/* this urb is terminated, clean up */
776 		dev_dbg(dev, "%s - urb shutting down with status: %d\n", __func__, status);
777 		return;
778 	default:
779 		dev_dbg(dev, "%s - nonzero urb status received: %d\n", __func__, status);
780 		goto exit;
781 	}
782 
783 	length = urb->actual_length;
784 	data = urb->transfer_buffer;
785 
786 	/* Moschip get 4 bytes
787 	 * Byte 1 IIR Port 1 (port.number is 0)
788 	 * Byte 2 IIR Port 2 (port.number is 1)
789 	 * Byte 3 --------------
790 	 * Byte 4 FIFO status for both */
791 
792 	/* the above description is inverted
793 	 * 	oneukum 2007-03-14 */
794 
795 	if (unlikely(length != 4)) {
796 		dev_dbg(dev, "Wrong data !!!\n");
797 		return;
798 	}
799 
800 	sp1 = data[3];
801 	sp2 = data[2];
802 
803 	if ((sp1 | sp2) & 0x01) {
804 		/* No Interrupt Pending in both the ports */
805 		dev_dbg(dev, "No Interrupt !!!\n");
806 	} else {
807 		switch (sp1 & 0x0f) {
808 		case SERIAL_IIR_RLS:
809 			dev_dbg(dev, "Serial Port 1: Receiver status error or address bit detected in 9-bit mode\n");
810 			break;
811 		case SERIAL_IIR_CTI:
812 			dev_dbg(dev, "Serial Port 1: Receiver time out\n");
813 			break;
814 		case SERIAL_IIR_MS:
815 			/* dev_dbg(dev, "Serial Port 1: Modem status change\n"); */
816 			break;
817 		}
818 
819 		switch (sp2 & 0x0f) {
820 		case SERIAL_IIR_RLS:
821 			dev_dbg(dev, "Serial Port 2: Receiver status error or address bit detected in 9-bit mode\n");
822 			break;
823 		case SERIAL_IIR_CTI:
824 			dev_dbg(dev, "Serial Port 2: Receiver time out\n");
825 			break;
826 		case SERIAL_IIR_MS:
827 			/* dev_dbg(dev, "Serial Port 2: Modem status change\n"); */
828 			break;
829 		}
830 	}
831 
832 exit:
833 	result = usb_submit_urb(urb, GFP_ATOMIC);
834 	if (result)
835 		dev_err(dev, "%s - Error %d submitting control urb\n", __func__, result);
836 }
837 
838 /*
839  * mos7715_interrupt_callback
840  *	this is the 7715's callback function for when we have received data on
841  *	the interrupt endpoint.
842  */
843 static void mos7715_interrupt_callback(struct urb *urb)
844 {
845 	int result;
846 	int length;
847 	int status = urb->status;
848 	struct device *dev = &urb->dev->dev;
849 	__u8 *data;
850 	__u8 iir;
851 
852 	switch (status) {
853 	case 0:
854 		/* success */
855 		break;
856 	case -ECONNRESET:
857 	case -ENOENT:
858 	case -ESHUTDOWN:
859 	case -ENODEV:
860 		/* this urb is terminated, clean up */
861 		dev_dbg(dev, "%s - urb shutting down with status: %d\n", __func__, status);
862 		return;
863 	default:
864 		dev_dbg(dev, "%s - nonzero urb status received: %d\n", __func__, status);
865 		goto exit;
866 	}
867 
868 	length = urb->actual_length;
869 	data = urb->transfer_buffer;
870 
871 	/* Structure of data from 7715 device:
872 	 * Byte 1: IIR serial Port
873 	 * Byte 2: unused
874 	 * Byte 2: DSR parallel port
875 	 * Byte 4: FIFO status for both */
876 
877 	if (unlikely(length != 4)) {
878 		dev_dbg(dev, "Wrong data !!!\n");
879 		return;
880 	}
881 
882 	iir = data[0];
883 	if (!(iir & 0x01)) {	/* serial port interrupt pending */
884 		switch (iir & 0x0f) {
885 		case SERIAL_IIR_RLS:
886 			dev_dbg(dev, "Serial Port: Receiver status error or address bit detected in 9-bit mode\n");
887 			break;
888 		case SERIAL_IIR_CTI:
889 			dev_dbg(dev, "Serial Port: Receiver time out\n");
890 			break;
891 		case SERIAL_IIR_MS:
892 			/* dev_dbg(dev, "Serial Port: Modem status change\n"); */
893 			break;
894 		}
895 	}
896 
897 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
898 	{       /* update local copy of DSR reg */
899 		struct usb_serial_port *port = urb->context;
900 		struct mos7715_parport *mos_parport = port->serial->private;
901 		if (unlikely(mos_parport == NULL))
902 			return;
903 		atomic_set(&mos_parport->shadowDSR, data[2]);
904 	}
905 #endif
906 
907 exit:
908 	result = usb_submit_urb(urb, GFP_ATOMIC);
909 	if (result)
910 		dev_err(dev, "%s - Error %d submitting control urb\n", __func__, result);
911 }
912 
913 /*
914  * mos7720_bulk_in_callback
915  *	this is the callback function for when we have received data on the
916  *	bulk in endpoint.
917  */
918 static void mos7720_bulk_in_callback(struct urb *urb)
919 {
920 	int retval;
921 	unsigned char *data ;
922 	struct usb_serial_port *port;
923 	int status = urb->status;
924 
925 	if (status) {
926 		dev_dbg(&urb->dev->dev, "nonzero read bulk status received: %d\n", status);
927 		return;
928 	}
929 
930 	port = urb->context;
931 
932 	dev_dbg(&port->dev, "Entering...%s\n", __func__);
933 
934 	data = urb->transfer_buffer;
935 
936 	if (urb->actual_length) {
937 		tty_insert_flip_string(&port->port, data, urb->actual_length);
938 		tty_flip_buffer_push(&port->port);
939 	}
940 
941 	if (port->read_urb->status != -EINPROGRESS) {
942 		retval = usb_submit_urb(port->read_urb, GFP_ATOMIC);
943 		if (retval)
944 			dev_dbg(&port->dev, "usb_submit_urb(read bulk) failed, retval = %d\n", retval);
945 	}
946 }
947 
948 /*
949  * mos7720_bulk_out_data_callback
950  *	this is the callback function for when we have finished sending serial
951  *	data on the bulk out endpoint.
952  */
953 static void mos7720_bulk_out_data_callback(struct urb *urb)
954 {
955 	struct moschip_port *mos7720_port;
956 	int status = urb->status;
957 
958 	if (status) {
959 		dev_dbg(&urb->dev->dev, "nonzero write bulk status received:%d\n", status);
960 		return;
961 	}
962 
963 	mos7720_port = urb->context;
964 	if (!mos7720_port) {
965 		dev_dbg(&urb->dev->dev, "NULL mos7720_port pointer\n");
966 		return ;
967 	}
968 
969 	if (mos7720_port->open)
970 		tty_port_tty_wakeup(&mos7720_port->port->port);
971 }
972 
973 static int mos77xx_calc_num_ports(struct usb_serial *serial,
974 					struct usb_serial_endpoints *epds)
975 {
976 	u16 product = le16_to_cpu(serial->dev->descriptor.idProduct);
977 
978 	if (product == MOSCHIP_DEVICE_ID_7715) {
979 		/*
980 		 * The 7715 uses the first bulk in/out endpoint pair for the
981 		 * parallel port, and the second for the serial port. We swap
982 		 * the endpoint descriptors here so that the the first and
983 		 * only registered port structure uses the serial-port
984 		 * endpoints.
985 		 */
986 		swap(epds->bulk_in[0], epds->bulk_in[1]);
987 		swap(epds->bulk_out[0], epds->bulk_out[1]);
988 
989 		return 1;
990 	}
991 
992 	return 2;
993 }
994 
995 static int mos7720_open(struct tty_struct *tty, struct usb_serial_port *port)
996 {
997 	struct usb_serial *serial;
998 	struct urb *urb;
999 	struct moschip_port *mos7720_port;
1000 	int response;
1001 	int port_number;
1002 	__u8 data;
1003 	int allocated_urbs = 0;
1004 	int j;
1005 
1006 	serial = port->serial;
1007 
1008 	mos7720_port = usb_get_serial_port_data(port);
1009 	if (mos7720_port == NULL)
1010 		return -ENODEV;
1011 
1012 	usb_clear_halt(serial->dev, port->write_urb->pipe);
1013 	usb_clear_halt(serial->dev, port->read_urb->pipe);
1014 
1015 	/* Initialising the write urb pool */
1016 	for (j = 0; j < NUM_URBS; ++j) {
1017 		urb = usb_alloc_urb(0, GFP_KERNEL);
1018 		mos7720_port->write_urb_pool[j] = urb;
1019 		if (!urb)
1020 			continue;
1021 
1022 		urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE,
1023 					       GFP_KERNEL);
1024 		if (!urb->transfer_buffer) {
1025 			usb_free_urb(mos7720_port->write_urb_pool[j]);
1026 			mos7720_port->write_urb_pool[j] = NULL;
1027 			continue;
1028 		}
1029 		allocated_urbs++;
1030 	}
1031 
1032 	if (!allocated_urbs)
1033 		return -ENOMEM;
1034 
1035 	 /* Initialize MCS7720 -- Write Init values to corresponding Registers
1036 	  *
1037 	  * Register Index
1038 	  * 0 : MOS7720_THR/MOS7720_RHR
1039 	  * 1 : MOS7720_IER
1040 	  * 2 : MOS7720_FCR
1041 	  * 3 : MOS7720_LCR
1042 	  * 4 : MOS7720_MCR
1043 	  * 5 : MOS7720_LSR
1044 	  * 6 : MOS7720_MSR
1045 	  * 7 : MOS7720_SPR
1046 	  *
1047 	  * 0x08 : SP1/2 Control Reg
1048 	  */
1049 	port_number = port->port_number;
1050 	read_mos_reg(serial, port_number, MOS7720_LSR, &data);
1051 
1052 	dev_dbg(&port->dev, "SS::%p LSR:%x\n", mos7720_port, data);
1053 
1054 	write_mos_reg(serial, dummy, MOS7720_SP1_REG, 0x02);
1055 	write_mos_reg(serial, dummy, MOS7720_SP2_REG, 0x02);
1056 
1057 	write_mos_reg(serial, port_number, MOS7720_IER, 0x00);
1058 	write_mos_reg(serial, port_number, MOS7720_FCR, 0x00);
1059 
1060 	write_mos_reg(serial, port_number, MOS7720_FCR, 0xcf);
1061 	mos7720_port->shadowLCR = 0x03;
1062 	write_mos_reg(serial, port_number, MOS7720_LCR,
1063 		      mos7720_port->shadowLCR);
1064 	mos7720_port->shadowMCR = 0x0b;
1065 	write_mos_reg(serial, port_number, MOS7720_MCR,
1066 		      mos7720_port->shadowMCR);
1067 
1068 	write_mos_reg(serial, port_number, MOS7720_SP_CONTROL_REG, 0x00);
1069 	read_mos_reg(serial, dummy, MOS7720_SP_CONTROL_REG, &data);
1070 	data = data | (port->port_number + 1);
1071 	write_mos_reg(serial, dummy, MOS7720_SP_CONTROL_REG, data);
1072 	mos7720_port->shadowLCR = 0x83;
1073 	write_mos_reg(serial, port_number, MOS7720_LCR,
1074 		      mos7720_port->shadowLCR);
1075 	write_mos_reg(serial, port_number, MOS7720_THR, 0x0c);
1076 	write_mos_reg(serial, port_number, MOS7720_IER, 0x00);
1077 	mos7720_port->shadowLCR = 0x03;
1078 	write_mos_reg(serial, port_number, MOS7720_LCR,
1079 		      mos7720_port->shadowLCR);
1080 	write_mos_reg(serial, port_number, MOS7720_IER, 0x0c);
1081 
1082 	response = usb_submit_urb(port->read_urb, GFP_KERNEL);
1083 	if (response)
1084 		dev_err(&port->dev, "%s - Error %d submitting read urb\n",
1085 							__func__, response);
1086 
1087 	/* initialize our port settings */
1088 	mos7720_port->shadowMCR = UART_MCR_OUT2; /* Must set to enable ints! */
1089 
1090 	/* send a open port command */
1091 	mos7720_port->open = 1;
1092 
1093 	return 0;
1094 }
1095 
1096 /*
1097  * mos7720_chars_in_buffer
1098  *	this function is called by the tty driver when it wants to know how many
1099  *	bytes of data we currently have outstanding in the port (data that has
1100  *	been written, but hasn't made it out the port yet)
1101  *	If successful, we return the number of bytes left to be written in the
1102  *	system,
1103  *	Otherwise we return a negative error number.
1104  */
1105 static int mos7720_chars_in_buffer(struct tty_struct *tty)
1106 {
1107 	struct usb_serial_port *port = tty->driver_data;
1108 	int i;
1109 	int chars = 0;
1110 	struct moschip_port *mos7720_port;
1111 
1112 	mos7720_port = usb_get_serial_port_data(port);
1113 	if (mos7720_port == NULL)
1114 		return 0;
1115 
1116 	for (i = 0; i < NUM_URBS; ++i) {
1117 		if (mos7720_port->write_urb_pool[i] &&
1118 		    mos7720_port->write_urb_pool[i]->status == -EINPROGRESS)
1119 			chars += URB_TRANSFER_BUFFER_SIZE;
1120 	}
1121 	dev_dbg(&port->dev, "%s - returns %d\n", __func__, chars);
1122 	return chars;
1123 }
1124 
1125 static void mos7720_close(struct usb_serial_port *port)
1126 {
1127 	struct usb_serial *serial;
1128 	struct moschip_port *mos7720_port;
1129 	int j;
1130 
1131 	serial = port->serial;
1132 
1133 	mos7720_port = usb_get_serial_port_data(port);
1134 	if (mos7720_port == NULL)
1135 		return;
1136 
1137 	for (j = 0; j < NUM_URBS; ++j)
1138 		usb_kill_urb(mos7720_port->write_urb_pool[j]);
1139 
1140 	/* Freeing Write URBs */
1141 	for (j = 0; j < NUM_URBS; ++j) {
1142 		if (mos7720_port->write_urb_pool[j]) {
1143 			kfree(mos7720_port->write_urb_pool[j]->transfer_buffer);
1144 			usb_free_urb(mos7720_port->write_urb_pool[j]);
1145 		}
1146 	}
1147 
1148 	/* While closing port, shutdown all bulk read, write  *
1149 	 * and interrupt read if they exists, otherwise nop   */
1150 	usb_kill_urb(port->write_urb);
1151 	usb_kill_urb(port->read_urb);
1152 
1153 	write_mos_reg(serial, port->port_number, MOS7720_MCR, 0x00);
1154 	write_mos_reg(serial, port->port_number, MOS7720_IER, 0x00);
1155 
1156 	mos7720_port->open = 0;
1157 }
1158 
1159 static void mos7720_break(struct tty_struct *tty, int break_state)
1160 {
1161 	struct usb_serial_port *port = tty->driver_data;
1162 	unsigned char data;
1163 	struct usb_serial *serial;
1164 	struct moschip_port *mos7720_port;
1165 
1166 	serial = port->serial;
1167 
1168 	mos7720_port = usb_get_serial_port_data(port);
1169 	if (mos7720_port == NULL)
1170 		return;
1171 
1172 	if (break_state == -1)
1173 		data = mos7720_port->shadowLCR | UART_LCR_SBC;
1174 	else
1175 		data = mos7720_port->shadowLCR & ~UART_LCR_SBC;
1176 
1177 	mos7720_port->shadowLCR  = data;
1178 	write_mos_reg(serial, port->port_number, MOS7720_LCR,
1179 		      mos7720_port->shadowLCR);
1180 }
1181 
1182 /*
1183  * mos7720_write_room
1184  *	this function is called by the tty driver when it wants to know how many
1185  *	bytes of data we can accept for a specific port.
1186  *	If successful, we return the amount of room that we have for this port
1187  *	Otherwise we return a negative error number.
1188  */
1189 static int mos7720_write_room(struct tty_struct *tty)
1190 {
1191 	struct usb_serial_port *port = tty->driver_data;
1192 	struct moschip_port *mos7720_port;
1193 	int room = 0;
1194 	int i;
1195 
1196 	mos7720_port = usb_get_serial_port_data(port);
1197 	if (mos7720_port == NULL)
1198 		return -ENODEV;
1199 
1200 	/* FIXME: Locking */
1201 	for (i = 0; i < NUM_URBS; ++i) {
1202 		if (mos7720_port->write_urb_pool[i] &&
1203 		    mos7720_port->write_urb_pool[i]->status != -EINPROGRESS)
1204 			room += URB_TRANSFER_BUFFER_SIZE;
1205 	}
1206 
1207 	dev_dbg(&port->dev, "%s - returns %d\n", __func__, room);
1208 	return room;
1209 }
1210 
1211 static int mos7720_write(struct tty_struct *tty, struct usb_serial_port *port,
1212 				 const unsigned char *data, int count)
1213 {
1214 	int status;
1215 	int i;
1216 	int bytes_sent = 0;
1217 	int transfer_size;
1218 
1219 	struct moschip_port *mos7720_port;
1220 	struct usb_serial *serial;
1221 	struct urb    *urb;
1222 	const unsigned char *current_position = data;
1223 
1224 	serial = port->serial;
1225 
1226 	mos7720_port = usb_get_serial_port_data(port);
1227 	if (mos7720_port == NULL)
1228 		return -ENODEV;
1229 
1230 	/* try to find a free urb in the list */
1231 	urb = NULL;
1232 
1233 	for (i = 0; i < NUM_URBS; ++i) {
1234 		if (mos7720_port->write_urb_pool[i] &&
1235 		    mos7720_port->write_urb_pool[i]->status != -EINPROGRESS) {
1236 			urb = mos7720_port->write_urb_pool[i];
1237 			dev_dbg(&port->dev, "URB:%d\n", i);
1238 			break;
1239 		}
1240 	}
1241 
1242 	if (urb == NULL) {
1243 		dev_dbg(&port->dev, "%s - no more free urbs\n", __func__);
1244 		goto exit;
1245 	}
1246 
1247 	if (urb->transfer_buffer == NULL) {
1248 		urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE,
1249 					       GFP_ATOMIC);
1250 		if (!urb->transfer_buffer)
1251 			goto exit;
1252 	}
1253 	transfer_size = min(count, URB_TRANSFER_BUFFER_SIZE);
1254 
1255 	memcpy(urb->transfer_buffer, current_position, transfer_size);
1256 	usb_serial_debug_data(&port->dev, __func__, transfer_size,
1257 			      urb->transfer_buffer);
1258 
1259 	/* fill urb with data and submit  */
1260 	usb_fill_bulk_urb(urb, serial->dev,
1261 			  usb_sndbulkpipe(serial->dev,
1262 					port->bulk_out_endpointAddress),
1263 			  urb->transfer_buffer, transfer_size,
1264 			  mos7720_bulk_out_data_callback, mos7720_port);
1265 
1266 	/* send it down the pipe */
1267 	status = usb_submit_urb(urb, GFP_ATOMIC);
1268 	if (status) {
1269 		dev_err_console(port, "%s - usb_submit_urb(write bulk) failed "
1270 			"with status = %d\n", __func__, status);
1271 		bytes_sent = status;
1272 		goto exit;
1273 	}
1274 	bytes_sent = transfer_size;
1275 
1276 exit:
1277 	return bytes_sent;
1278 }
1279 
1280 static void mos7720_throttle(struct tty_struct *tty)
1281 {
1282 	struct usb_serial_port *port = tty->driver_data;
1283 	struct moschip_port *mos7720_port;
1284 	int status;
1285 
1286 	mos7720_port = usb_get_serial_port_data(port);
1287 
1288 	if (mos7720_port == NULL)
1289 		return;
1290 
1291 	if (!mos7720_port->open) {
1292 		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
1293 		return;
1294 	}
1295 
1296 	/* if we are implementing XON/XOFF, send the stop character */
1297 	if (I_IXOFF(tty)) {
1298 		unsigned char stop_char = STOP_CHAR(tty);
1299 		status = mos7720_write(tty, port, &stop_char, 1);
1300 		if (status <= 0)
1301 			return;
1302 	}
1303 
1304 	/* if we are implementing RTS/CTS, toggle that line */
1305 	if (C_CRTSCTS(tty)) {
1306 		mos7720_port->shadowMCR &= ~UART_MCR_RTS;
1307 		write_mos_reg(port->serial, port->port_number, MOS7720_MCR,
1308 			      mos7720_port->shadowMCR);
1309 	}
1310 }
1311 
1312 static void mos7720_unthrottle(struct tty_struct *tty)
1313 {
1314 	struct usb_serial_port *port = tty->driver_data;
1315 	struct moschip_port *mos7720_port = usb_get_serial_port_data(port);
1316 	int status;
1317 
1318 	if (mos7720_port == NULL)
1319 		return;
1320 
1321 	if (!mos7720_port->open) {
1322 		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
1323 		return;
1324 	}
1325 
1326 	/* if we are implementing XON/XOFF, send the start character */
1327 	if (I_IXOFF(tty)) {
1328 		unsigned char start_char = START_CHAR(tty);
1329 		status = mos7720_write(tty, port, &start_char, 1);
1330 		if (status <= 0)
1331 			return;
1332 	}
1333 
1334 	/* if we are implementing RTS/CTS, toggle that line */
1335 	if (C_CRTSCTS(tty)) {
1336 		mos7720_port->shadowMCR |= UART_MCR_RTS;
1337 		write_mos_reg(port->serial, port->port_number, MOS7720_MCR,
1338 			      mos7720_port->shadowMCR);
1339 	}
1340 }
1341 
1342 /* FIXME: this function does not work */
1343 static int set_higher_rates(struct moschip_port *mos7720_port,
1344 			    unsigned int baud)
1345 {
1346 	struct usb_serial_port *port;
1347 	struct usb_serial *serial;
1348 	int port_number;
1349 	enum mos_regs sp_reg;
1350 	if (mos7720_port == NULL)
1351 		return -EINVAL;
1352 
1353 	port = mos7720_port->port;
1354 	serial = port->serial;
1355 
1356 	 /***********************************************
1357 	 *      Init Sequence for higher rates
1358 	 ***********************************************/
1359 	dev_dbg(&port->dev, "Sending Setting Commands ..........\n");
1360 	port_number = port->port_number;
1361 
1362 	write_mos_reg(serial, port_number, MOS7720_IER, 0x00);
1363 	write_mos_reg(serial, port_number, MOS7720_FCR, 0x00);
1364 	write_mos_reg(serial, port_number, MOS7720_FCR, 0xcf);
1365 	mos7720_port->shadowMCR = 0x0b;
1366 	write_mos_reg(serial, port_number, MOS7720_MCR,
1367 		      mos7720_port->shadowMCR);
1368 	write_mos_reg(serial, dummy, MOS7720_SP_CONTROL_REG, 0x00);
1369 
1370 	/***********************************************
1371 	 *              Set for higher rates           *
1372 	 ***********************************************/
1373 	/* writing baud rate verbatum into uart clock field clearly not right */
1374 	if (port_number == 0)
1375 		sp_reg = MOS7720_SP1_REG;
1376 	else
1377 		sp_reg = MOS7720_SP2_REG;
1378 	write_mos_reg(serial, dummy, sp_reg, baud * 0x10);
1379 	write_mos_reg(serial, dummy, MOS7720_SP_CONTROL_REG, 0x03);
1380 	mos7720_port->shadowMCR = 0x2b;
1381 	write_mos_reg(serial, port_number, MOS7720_MCR,
1382 		      mos7720_port->shadowMCR);
1383 
1384 	/***********************************************
1385 	 *              Set DLL/DLM
1386 	 ***********************************************/
1387 	mos7720_port->shadowLCR = mos7720_port->shadowLCR | UART_LCR_DLAB;
1388 	write_mos_reg(serial, port_number, MOS7720_LCR,
1389 		      mos7720_port->shadowLCR);
1390 	write_mos_reg(serial, port_number, MOS7720_DLL, 0x01);
1391 	write_mos_reg(serial, port_number, MOS7720_DLM, 0x00);
1392 	mos7720_port->shadowLCR = mos7720_port->shadowLCR & ~UART_LCR_DLAB;
1393 	write_mos_reg(serial, port_number, MOS7720_LCR,
1394 		      mos7720_port->shadowLCR);
1395 
1396 	return 0;
1397 }
1398 
1399 /* baud rate information */
1400 struct divisor_table_entry {
1401 	__u32  baudrate;
1402 	__u16  divisor;
1403 };
1404 
1405 /* Define table of divisors for moschip 7720 hardware	   *
1406  * These assume a 3.6864MHz crystal, the standard /16, and *
1407  * MCR.7 = 0.						   */
1408 static const struct divisor_table_entry divisor_table[] = {
1409 	{   50,		2304},
1410 	{   110,	1047},	/* 2094.545455 => 230450   => .0217 % over */
1411 	{   134,	857},	/* 1713.011152 => 230398.5 => .00065% under */
1412 	{   150,	768},
1413 	{   300,	384},
1414 	{   600,	192},
1415 	{   1200,	96},
1416 	{   1800,	64},
1417 	{   2400,	48},
1418 	{   4800,	24},
1419 	{   7200,	16},
1420 	{   9600,	12},
1421 	{   19200,	6},
1422 	{   38400,	3},
1423 	{   57600,	2},
1424 	{   115200,	1},
1425 };
1426 
1427 /*****************************************************************************
1428  * calc_baud_rate_divisor
1429  *	this function calculates the proper baud rate divisor for the specified
1430  *	baud rate.
1431  *****************************************************************************/
1432 static int calc_baud_rate_divisor(struct usb_serial_port *port, int baudrate, int *divisor)
1433 {
1434 	int i;
1435 	__u16 custom;
1436 	__u16 round1;
1437 	__u16 round;
1438 
1439 
1440 	dev_dbg(&port->dev, "%s - %d\n", __func__, baudrate);
1441 
1442 	for (i = 0; i < ARRAY_SIZE(divisor_table); i++) {
1443 		if (divisor_table[i].baudrate == baudrate) {
1444 			*divisor = divisor_table[i].divisor;
1445 			return 0;
1446 		}
1447 	}
1448 
1449 	/* After trying for all the standard baud rates    *
1450 	 * Try calculating the divisor for this baud rate  */
1451 	if (baudrate > 75 &&  baudrate < 230400) {
1452 		/* get the divisor */
1453 		custom = (__u16)(230400L  / baudrate);
1454 
1455 		/* Check for round off */
1456 		round1 = (__u16)(2304000L / baudrate);
1457 		round = (__u16)(round1 - (custom * 10));
1458 		if (round > 4)
1459 			custom++;
1460 		*divisor = custom;
1461 
1462 		dev_dbg(&port->dev, "Baud %d = %d\n", baudrate, custom);
1463 		return 0;
1464 	}
1465 
1466 	dev_dbg(&port->dev, "Baud calculation Failed...\n");
1467 	return -EINVAL;
1468 }
1469 
1470 /*
1471  * send_cmd_write_baud_rate
1472  *	this function sends the proper command to change the baud rate of the
1473  *	specified port.
1474  */
1475 static int send_cmd_write_baud_rate(struct moschip_port *mos7720_port,
1476 				    int baudrate)
1477 {
1478 	struct usb_serial_port *port;
1479 	struct usb_serial *serial;
1480 	int divisor;
1481 	int status;
1482 	unsigned char number;
1483 
1484 	if (mos7720_port == NULL)
1485 		return -1;
1486 
1487 	port = mos7720_port->port;
1488 	serial = port->serial;
1489 
1490 	number = port->port_number;
1491 	dev_dbg(&port->dev, "%s - baud = %d\n", __func__, baudrate);
1492 
1493 	/* Calculate the Divisor */
1494 	status = calc_baud_rate_divisor(port, baudrate, &divisor);
1495 	if (status) {
1496 		dev_err(&port->dev, "%s - bad baud rate\n", __func__);
1497 		return status;
1498 	}
1499 
1500 	/* Enable access to divisor latch */
1501 	mos7720_port->shadowLCR = mos7720_port->shadowLCR | UART_LCR_DLAB;
1502 	write_mos_reg(serial, number, MOS7720_LCR, mos7720_port->shadowLCR);
1503 
1504 	/* Write the divisor */
1505 	write_mos_reg(serial, number, MOS7720_DLL, (__u8)(divisor & 0xff));
1506 	write_mos_reg(serial, number, MOS7720_DLM,
1507 		      (__u8)((divisor & 0xff00) >> 8));
1508 
1509 	/* Disable access to divisor latch */
1510 	mos7720_port->shadowLCR = mos7720_port->shadowLCR & ~UART_LCR_DLAB;
1511 	write_mos_reg(serial, number, MOS7720_LCR, mos7720_port->shadowLCR);
1512 
1513 	return status;
1514 }
1515 
1516 /*
1517  * change_port_settings
1518  *	This routine is called to set the UART on the device to match
1519  *      the specified new settings.
1520  */
1521 static void change_port_settings(struct tty_struct *tty,
1522 				 struct moschip_port *mos7720_port,
1523 				 struct ktermios *old_termios)
1524 {
1525 	struct usb_serial_port *port;
1526 	struct usb_serial *serial;
1527 	int baud;
1528 	unsigned cflag;
1529 	unsigned iflag;
1530 	__u8 mask = 0xff;
1531 	__u8 lData;
1532 	__u8 lParity;
1533 	__u8 lStop;
1534 	int status;
1535 	int port_number;
1536 
1537 	if (mos7720_port == NULL)
1538 		return ;
1539 
1540 	port = mos7720_port->port;
1541 	serial = port->serial;
1542 	port_number = port->port_number;
1543 
1544 	if (!mos7720_port->open) {
1545 		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
1546 		return;
1547 	}
1548 
1549 	lData = UART_LCR_WLEN8;
1550 	lStop = 0x00;	/* 1 stop bit */
1551 	lParity = 0x00;	/* No parity */
1552 
1553 	cflag = tty->termios.c_cflag;
1554 	iflag = tty->termios.c_iflag;
1555 
1556 	/* Change the number of bits */
1557 	switch (cflag & CSIZE) {
1558 	case CS5:
1559 		lData = UART_LCR_WLEN5;
1560 		mask = 0x1f;
1561 		break;
1562 
1563 	case CS6:
1564 		lData = UART_LCR_WLEN6;
1565 		mask = 0x3f;
1566 		break;
1567 
1568 	case CS7:
1569 		lData = UART_LCR_WLEN7;
1570 		mask = 0x7f;
1571 		break;
1572 	default:
1573 	case CS8:
1574 		lData = UART_LCR_WLEN8;
1575 		break;
1576 	}
1577 
1578 	/* Change the Parity bit */
1579 	if (cflag & PARENB) {
1580 		if (cflag & PARODD) {
1581 			lParity = UART_LCR_PARITY;
1582 			dev_dbg(&port->dev, "%s - parity = odd\n", __func__);
1583 		} else {
1584 			lParity = (UART_LCR_EPAR | UART_LCR_PARITY);
1585 			dev_dbg(&port->dev, "%s - parity = even\n", __func__);
1586 		}
1587 
1588 	} else {
1589 		dev_dbg(&port->dev, "%s - parity = none\n", __func__);
1590 	}
1591 
1592 	if (cflag & CMSPAR)
1593 		lParity = lParity | 0x20;
1594 
1595 	/* Change the Stop bit */
1596 	if (cflag & CSTOPB) {
1597 		lStop = UART_LCR_STOP;
1598 		dev_dbg(&port->dev, "%s - stop bits = 2\n", __func__);
1599 	} else {
1600 		lStop = 0x00;
1601 		dev_dbg(&port->dev, "%s - stop bits = 1\n", __func__);
1602 	}
1603 
1604 #define LCR_BITS_MASK		0x03	/* Mask for bits/char field */
1605 #define LCR_STOP_MASK		0x04	/* Mask for stop bits field */
1606 #define LCR_PAR_MASK		0x38	/* Mask for parity field */
1607 
1608 	/* Update the LCR with the correct value */
1609 	mos7720_port->shadowLCR &=
1610 		~(LCR_BITS_MASK | LCR_STOP_MASK | LCR_PAR_MASK);
1611 	mos7720_port->shadowLCR |= (lData | lParity | lStop);
1612 
1613 
1614 	/* Disable Interrupts */
1615 	write_mos_reg(serial, port_number, MOS7720_IER, 0x00);
1616 	write_mos_reg(serial, port_number, MOS7720_FCR, 0x00);
1617 	write_mos_reg(serial, port_number, MOS7720_FCR, 0xcf);
1618 
1619 	/* Send the updated LCR value to the mos7720 */
1620 	write_mos_reg(serial, port_number, MOS7720_LCR,
1621 		      mos7720_port->shadowLCR);
1622 	mos7720_port->shadowMCR = 0x0b;
1623 	write_mos_reg(serial, port_number, MOS7720_MCR,
1624 		      mos7720_port->shadowMCR);
1625 
1626 	/* set up the MCR register and send it to the mos7720 */
1627 	mos7720_port->shadowMCR = UART_MCR_OUT2;
1628 	if (cflag & CBAUD)
1629 		mos7720_port->shadowMCR |= (UART_MCR_DTR | UART_MCR_RTS);
1630 
1631 	if (cflag & CRTSCTS) {
1632 		mos7720_port->shadowMCR |= (UART_MCR_XONANY);
1633 		/* To set hardware flow control to the specified *
1634 		 * serial port, in SP1/2_CONTROL_REG             */
1635 		if (port_number)
1636 			write_mos_reg(serial, dummy, MOS7720_SP_CONTROL_REG,
1637 				      0x01);
1638 		else
1639 			write_mos_reg(serial, dummy, MOS7720_SP_CONTROL_REG,
1640 				      0x02);
1641 
1642 	} else
1643 		mos7720_port->shadowMCR &= ~(UART_MCR_XONANY);
1644 
1645 	write_mos_reg(serial, port_number, MOS7720_MCR,
1646 		      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, MOS7720_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, MOS7720_IER, 0x0c);
1671 
1672 	if (port->read_urb->status != -EINPROGRESS) {
1673 		status = usb_submit_urb(port->read_urb, GFP_KERNEL);
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 	struct usb_serial *serial;
1689 	struct moschip_port *mos7720_port;
1690 
1691 	serial = port->serial;
1692 
1693 	mos7720_port = usb_get_serial_port_data(port);
1694 
1695 	if (mos7720_port == NULL)
1696 		return;
1697 
1698 	if (!mos7720_port->open) {
1699 		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
1700 		return;
1701 	}
1702 
1703 	/* change the port settings to the new ones specified */
1704 	change_port_settings(tty, mos7720_port, old_termios);
1705 
1706 	if (port->read_urb->status != -EINPROGRESS) {
1707 		status = usb_submit_urb(port->read_urb, GFP_KERNEL);
1708 		if (status)
1709 			dev_dbg(&port->dev, "usb_submit_urb(read bulk) failed, status = %d\n", status);
1710 	}
1711 }
1712 
1713 /*
1714  * get_lsr_info - get line status register info
1715  *
1716  * Purpose: Let user call ioctl() to get info when the UART physically
1717  * 	    is emptied.  On bus types like RS485, the transmitter must
1718  * 	    release the bus after transmitting. This must be done when
1719  * 	    the transmit shift register is empty, not be done when the
1720  * 	    transmit holding register is empty.  This functionality
1721  * 	    allows an RS485 driver to be written in user space.
1722  */
1723 static int get_lsr_info(struct tty_struct *tty,
1724 		struct moschip_port *mos7720_port, unsigned int __user *value)
1725 {
1726 	struct usb_serial_port *port = tty->driver_data;
1727 	unsigned int result = 0;
1728 	unsigned char data = 0;
1729 	int port_number = port->port_number;
1730 	int count;
1731 
1732 	count = mos7720_chars_in_buffer(tty);
1733 	if (count == 0) {
1734 		read_mos_reg(port->serial, port_number, MOS7720_LSR, &data);
1735 		if ((data & (UART_LSR_TEMT | UART_LSR_THRE))
1736 					== (UART_LSR_TEMT | UART_LSR_THRE)) {
1737 			dev_dbg(&port->dev, "%s -- Empty\n", __func__);
1738 			result = TIOCSER_TEMT;
1739 		}
1740 	}
1741 	if (copy_to_user(value, &result, sizeof(int)))
1742 		return -EFAULT;
1743 	return 0;
1744 }
1745 
1746 static int mos7720_tiocmget(struct tty_struct *tty)
1747 {
1748 	struct usb_serial_port *port = tty->driver_data;
1749 	struct moschip_port *mos7720_port = usb_get_serial_port_data(port);
1750 	unsigned int result = 0;
1751 	unsigned int mcr ;
1752 	unsigned int msr ;
1753 
1754 	mcr = mos7720_port->shadowMCR;
1755 	msr = mos7720_port->shadowMSR;
1756 
1757 	result = ((mcr & UART_MCR_DTR)  ? TIOCM_DTR : 0)   /* 0x002 */
1758 	  | ((mcr & UART_MCR_RTS)   ? TIOCM_RTS : 0)   /* 0x004 */
1759 	  | ((msr & UART_MSR_CTS)   ? TIOCM_CTS : 0)   /* 0x020 */
1760 	  | ((msr & UART_MSR_DCD)   ? TIOCM_CAR : 0)   /* 0x040 */
1761 	  | ((msr & UART_MSR_RI)    ? TIOCM_RI :  0)   /* 0x080 */
1762 	  | ((msr & UART_MSR_DSR)   ? TIOCM_DSR : 0);  /* 0x100 */
1763 
1764 	return result;
1765 }
1766 
1767 static int mos7720_tiocmset(struct tty_struct *tty,
1768 			    unsigned int set, unsigned int clear)
1769 {
1770 	struct usb_serial_port *port = tty->driver_data;
1771 	struct moschip_port *mos7720_port = usb_get_serial_port_data(port);
1772 	unsigned int mcr ;
1773 
1774 	mcr = mos7720_port->shadowMCR;
1775 
1776 	if (set & TIOCM_RTS)
1777 		mcr |= UART_MCR_RTS;
1778 	if (set & TIOCM_DTR)
1779 		mcr |= UART_MCR_DTR;
1780 	if (set & TIOCM_LOOP)
1781 		mcr |= UART_MCR_LOOP;
1782 
1783 	if (clear & TIOCM_RTS)
1784 		mcr &= ~UART_MCR_RTS;
1785 	if (clear & TIOCM_DTR)
1786 		mcr &= ~UART_MCR_DTR;
1787 	if (clear & TIOCM_LOOP)
1788 		mcr &= ~UART_MCR_LOOP;
1789 
1790 	mos7720_port->shadowMCR = mcr;
1791 	write_mos_reg(port->serial, port->port_number, MOS7720_MCR,
1792 		      mos7720_port->shadowMCR);
1793 
1794 	return 0;
1795 }
1796 
1797 static int set_modem_info(struct moschip_port *mos7720_port, unsigned int cmd,
1798 			  unsigned int __user *value)
1799 {
1800 	unsigned int mcr;
1801 	unsigned int arg;
1802 
1803 	struct usb_serial_port *port;
1804 
1805 	if (mos7720_port == NULL)
1806 		return -1;
1807 
1808 	port = (struct usb_serial_port *)mos7720_port->port;
1809 	mcr = mos7720_port->shadowMCR;
1810 
1811 	if (copy_from_user(&arg, value, sizeof(int)))
1812 		return -EFAULT;
1813 
1814 	switch (cmd) {
1815 	case TIOCMBIS:
1816 		if (arg & TIOCM_RTS)
1817 			mcr |= UART_MCR_RTS;
1818 		if (arg & TIOCM_DTR)
1819 			mcr |= UART_MCR_RTS;
1820 		if (arg & TIOCM_LOOP)
1821 			mcr |= UART_MCR_LOOP;
1822 		break;
1823 
1824 	case TIOCMBIC:
1825 		if (arg & TIOCM_RTS)
1826 			mcr &= ~UART_MCR_RTS;
1827 		if (arg & TIOCM_DTR)
1828 			mcr &= ~UART_MCR_RTS;
1829 		if (arg & TIOCM_LOOP)
1830 			mcr &= ~UART_MCR_LOOP;
1831 		break;
1832 
1833 	}
1834 
1835 	mos7720_port->shadowMCR = mcr;
1836 	write_mos_reg(port->serial, port->port_number, MOS7720_MCR,
1837 		      mos7720_port->shadowMCR);
1838 
1839 	return 0;
1840 }
1841 
1842 static int get_serial_info(struct moschip_port *mos7720_port,
1843 			   struct serial_struct __user *retinfo)
1844 {
1845 	struct serial_struct tmp;
1846 
1847 	memset(&tmp, 0, sizeof(tmp));
1848 
1849 	tmp.type		= PORT_16550A;
1850 	tmp.line		= mos7720_port->port->minor;
1851 	tmp.port		= mos7720_port->port->port_number;
1852 	tmp.irq			= 0;
1853 	tmp.xmit_fifo_size	= NUM_URBS * URB_TRANSFER_BUFFER_SIZE;
1854 	tmp.baud_base		= 9600;
1855 	tmp.close_delay		= 5*HZ;
1856 	tmp.closing_wait	= 30*HZ;
1857 
1858 	if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
1859 		return -EFAULT;
1860 	return 0;
1861 }
1862 
1863 static int mos7720_ioctl(struct tty_struct *tty,
1864 			 unsigned int cmd, unsigned long arg)
1865 {
1866 	struct usb_serial_port *port = tty->driver_data;
1867 	struct moschip_port *mos7720_port;
1868 
1869 	mos7720_port = usb_get_serial_port_data(port);
1870 	if (mos7720_port == NULL)
1871 		return -ENODEV;
1872 
1873 	switch (cmd) {
1874 	case TIOCSERGETLSR:
1875 		dev_dbg(&port->dev, "%s TIOCSERGETLSR\n", __func__);
1876 		return get_lsr_info(tty, mos7720_port,
1877 					(unsigned int __user *)arg);
1878 
1879 	/* FIXME: These should be using the mode methods */
1880 	case TIOCMBIS:
1881 	case TIOCMBIC:
1882 		dev_dbg(&port->dev, "%s TIOCMSET/TIOCMBIC/TIOCMSET\n", __func__);
1883 		return set_modem_info(mos7720_port, cmd,
1884 				      (unsigned int __user *)arg);
1885 
1886 	case TIOCGSERIAL:
1887 		dev_dbg(&port->dev, "%s TIOCGSERIAL\n", __func__);
1888 		return get_serial_info(mos7720_port,
1889 				       (struct serial_struct __user *)arg);
1890 	}
1891 
1892 	return -ENOIOCTLCMD;
1893 }
1894 
1895 static int mos7720_startup(struct usb_serial *serial)
1896 {
1897 	struct usb_device *dev;
1898 	char data;
1899 	u16 product;
1900 	int ret_val;
1901 
1902 	product = le16_to_cpu(serial->dev->descriptor.idProduct);
1903 	dev = serial->dev;
1904 
1905 	/* setting configuration feature to one */
1906 	usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
1907 			(__u8)0x03, 0x00, 0x01, 0x00, NULL, 0x00, 5000);
1908 
1909 	if (product == MOSCHIP_DEVICE_ID_7715) {
1910 		struct urb *urb = serial->port[0]->interrupt_in_urb;
1911 
1912 		urb->complete = mos7715_interrupt_callback;
1913 
1914 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
1915 		ret_val = mos7715_parport_init(serial);
1916 		if (ret_val < 0)
1917 			return ret_val;
1918 #endif
1919 	}
1920 	/* start the interrupt urb */
1921 	ret_val = usb_submit_urb(serial->port[0]->interrupt_in_urb, GFP_KERNEL);
1922 	if (ret_val) {
1923 		dev_err(&dev->dev, "failed to submit interrupt urb: %d\n",
1924 			ret_val);
1925 	}
1926 
1927 	/* LSR For Port 1 */
1928 	read_mos_reg(serial, 0, MOS7720_LSR, &data);
1929 	dev_dbg(&dev->dev, "LSR:%x\n", data);
1930 
1931 	return 0;
1932 }
1933 
1934 static void mos7720_release(struct usb_serial *serial)
1935 {
1936 	usb_kill_urb(serial->port[0]->interrupt_in_urb);
1937 
1938 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
1939 	/* close the parallel port */
1940 
1941 	if (le16_to_cpu(serial->dev->descriptor.idProduct)
1942 	    == MOSCHIP_DEVICE_ID_7715) {
1943 		struct urbtracker *urbtrack;
1944 		unsigned long flags;
1945 		struct mos7715_parport *mos_parport =
1946 			usb_get_serial_data(serial);
1947 
1948 		/* prevent NULL ptr dereference in port callbacks */
1949 		spin_lock(&release_lock);
1950 		mos_parport->pp->private_data = NULL;
1951 		spin_unlock(&release_lock);
1952 
1953 		/* wait for synchronous usb calls to return */
1954 		if (mos_parport->msg_pending)
1955 			wait_for_completion_timeout(&mos_parport->syncmsg_compl,
1956 					    msecs_to_jiffies(MOS_WDR_TIMEOUT));
1957 
1958 		parport_remove_port(mos_parport->pp);
1959 		usb_set_serial_data(serial, NULL);
1960 		mos_parport->serial = NULL;
1961 
1962 		/* if tasklet currently scheduled, wait for it to complete */
1963 		tasklet_kill(&mos_parport->urb_tasklet);
1964 
1965 		/* unlink any urbs sent by the tasklet  */
1966 		spin_lock_irqsave(&mos_parport->listlock, flags);
1967 		list_for_each_entry(urbtrack,
1968 				    &mos_parport->active_urbs,
1969 				    urblist_entry)
1970 			usb_unlink_urb(urbtrack->urb);
1971 		spin_unlock_irqrestore(&mos_parport->listlock, flags);
1972 		parport_del_port(mos_parport->pp);
1973 
1974 		kref_put(&mos_parport->ref_count, destroy_mos_parport);
1975 	}
1976 #endif
1977 }
1978 
1979 static int mos7720_port_probe(struct usb_serial_port *port)
1980 {
1981 	struct moschip_port *mos7720_port;
1982 
1983 	mos7720_port = kzalloc(sizeof(*mos7720_port), GFP_KERNEL);
1984 	if (!mos7720_port)
1985 		return -ENOMEM;
1986 
1987 	mos7720_port->port = port;
1988 
1989 	usb_set_serial_port_data(port, mos7720_port);
1990 
1991 	return 0;
1992 }
1993 
1994 static int mos7720_port_remove(struct usb_serial_port *port)
1995 {
1996 	struct moschip_port *mos7720_port;
1997 
1998 	mos7720_port = usb_get_serial_port_data(port);
1999 	kfree(mos7720_port);
2000 
2001 	return 0;
2002 }
2003 
2004 static struct usb_serial_driver moschip7720_2port_driver = {
2005 	.driver = {
2006 		.owner =	THIS_MODULE,
2007 		.name =		"moschip7720",
2008 	},
2009 	.description		= "Moschip 2 port adapter",
2010 	.id_table		= id_table,
2011 	.num_bulk_in		= 2,
2012 	.num_bulk_out		= 2,
2013 	.num_interrupt_in	= 1,
2014 	.calc_num_ports		= mos77xx_calc_num_ports,
2015 	.open			= mos7720_open,
2016 	.close			= mos7720_close,
2017 	.throttle		= mos7720_throttle,
2018 	.unthrottle		= mos7720_unthrottle,
2019 	.attach			= mos7720_startup,
2020 	.release		= mos7720_release,
2021 	.port_probe		= mos7720_port_probe,
2022 	.port_remove		= mos7720_port_remove,
2023 	.ioctl			= mos7720_ioctl,
2024 	.tiocmget		= mos7720_tiocmget,
2025 	.tiocmset		= mos7720_tiocmset,
2026 	.set_termios		= mos7720_set_termios,
2027 	.write			= mos7720_write,
2028 	.write_room		= mos7720_write_room,
2029 	.chars_in_buffer	= mos7720_chars_in_buffer,
2030 	.break_ctl		= mos7720_break,
2031 	.read_bulk_callback	= mos7720_bulk_in_callback,
2032 	.read_int_callback	= mos7720_interrupt_callback,
2033 };
2034 
2035 static struct usb_serial_driver * const serial_drivers[] = {
2036 	&moschip7720_2port_driver, NULL
2037 };
2038 
2039 module_usb_serial_driver(serial_drivers, id_table);
2040 
2041 MODULE_AUTHOR(DRIVER_AUTHOR);
2042 MODULE_DESCRIPTION(DRIVER_DESC);
2043 MODULE_LICENSE("GPL v2");
2044