xref: /openbmc/linux/drivers/usb/serial/mos7720.c (revision 8730046c)
1 /*
2  * mos7720.c
3  *   Controls the Moschip 7720 usb to dual port serial converter
4  *
5  * Copyright 2006 Moschip Semiconductor Tech. Ltd.
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation, version 2 of the License.
10  *
11  * Developed by:
12  * 	Vijaya Kumar <vijaykumar.gn@gmail.com>
13  *	Ajay Kumar <naanuajay@yahoo.com>
14  *	Gurudeva <ngurudeva@yahoo.com>
15  *
16  * Cleaned up from the original by:
17  *	Greg Kroah-Hartman <gregkh@suse.de>
18  *
19  * Originally based on drivers/usb/serial/io_edgeport.c which is:
20  *	Copyright (C) 2000 Inside Out Networks, All rights reserved.
21  *	Copyright (C) 2001-2002 Greg Kroah-Hartman <greg@kroah.com>
22  */
23 #include <linux/kernel.h>
24 #include <linux/errno.h>
25 #include <linux/slab.h>
26 #include <linux/tty.h>
27 #include <linux/tty_driver.h>
28 #include <linux/tty_flip.h>
29 #include <linux/module.h>
30 #include <linux/spinlock.h>
31 #include <linux/serial.h>
32 #include <linux/serial_reg.h>
33 #include <linux/usb.h>
34 #include <linux/usb/serial.h>
35 #include <linux/uaccess.h>
36 #include <linux/parport.h>
37 
38 #define DRIVER_AUTHOR "Aspire Communications pvt Ltd."
39 #define DRIVER_DESC "Moschip USB Serial Driver"
40 
41 /* default urb timeout */
42 #define MOS_WDR_TIMEOUT	5000
43 
44 #define MOS_MAX_PORT	0x02
45 #define MOS_WRITE	0x0E
46 #define MOS_READ	0x0D
47 
48 /* Interrupt Routines Defines	*/
49 #define SERIAL_IIR_RLS	0x06
50 #define SERIAL_IIR_RDA	0x04
51 #define SERIAL_IIR_CTI	0x0c
52 #define SERIAL_IIR_THR	0x02
53 #define SERIAL_IIR_MS	0x00
54 
55 #define NUM_URBS			16	/* URB Count */
56 #define URB_TRANSFER_BUFFER_SIZE	32	/* URB Size */
57 
58 /* This structure holds all of the local serial port information */
59 struct moschip_port {
60 	__u8	shadowLCR;		/* last LCR value received */
61 	__u8	shadowMCR;		/* last MCR value received */
62 	__u8	shadowMSR;		/* last MSR value received */
63 	char			open;
64 	struct usb_serial_port	*port;	/* loop back to the owner */
65 	struct urb		*write_urb_pool[NUM_URBS];
66 };
67 
68 #define USB_VENDOR_ID_MOSCHIP		0x9710
69 #define MOSCHIP_DEVICE_ID_7720		0x7720
70 #define MOSCHIP_DEVICE_ID_7715		0x7715
71 
72 static const struct usb_device_id id_table[] = {
73 	{ USB_DEVICE(USB_VENDOR_ID_MOSCHIP, MOSCHIP_DEVICE_ID_7720) },
74 	{ USB_DEVICE(USB_VENDOR_ID_MOSCHIP, MOSCHIP_DEVICE_ID_7715) },
75 	{ } /* terminating entry */
76 };
77 MODULE_DEVICE_TABLE(usb, id_table);
78 
79 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
80 
81 /* initial values for parport regs */
82 #define DCR_INIT_VAL       0x0c	/* SLCTIN, nINIT */
83 #define ECR_INIT_VAL       0x00	/* SPP mode */
84 
85 struct urbtracker {
86 	struct mos7715_parport  *mos_parport;
87 	struct list_head        urblist_entry;
88 	struct kref             ref_count;
89 	struct urb              *urb;
90 	struct usb_ctrlrequest	*setup;
91 };
92 
93 enum mos7715_pp_modes {
94 	SPP = 0<<5,
95 	PS2 = 1<<5,      /* moschip calls this 'NIBBLE' mode */
96 	PPF = 2<<5,	 /* moschip calls this 'CB-FIFO mode */
97 };
98 
99 struct mos7715_parport {
100 	struct parport          *pp;	       /* back to containing struct */
101 	struct kref             ref_count;     /* to instance of this struct */
102 	struct list_head        deferred_urbs; /* list deferred async urbs */
103 	struct list_head        active_urbs;   /* list async urbs in flight */
104 	spinlock_t              listlock;      /* protects list access */
105 	bool                    msg_pending;   /* usb sync call pending */
106 	struct completion       syncmsg_compl; /* usb sync call completed */
107 	struct tasklet_struct   urb_tasklet;   /* for sending deferred urbs */
108 	struct usb_serial       *serial;       /* back to containing struct */
109 	__u8	                shadowECR;     /* parallel port regs... */
110 	__u8	                shadowDCR;
111 	atomic_t                shadowDSR;     /* updated in int-in callback */
112 };
113 
114 /* lock guards against dereferencing NULL ptr in parport ops callbacks */
115 static DEFINE_SPINLOCK(release_lock);
116 
117 #endif	/* CONFIG_USB_SERIAL_MOS7715_PARPORT */
118 
119 static const unsigned int dummy; /* for clarity in register access fns */
120 
121 enum mos_regs {
122 	MOS7720_THR,		  /* serial port regs */
123 	MOS7720_RHR,
124 	MOS7720_IER,
125 	MOS7720_FCR,
126 	MOS7720_ISR,
127 	MOS7720_LCR,
128 	MOS7720_MCR,
129 	MOS7720_LSR,
130 	MOS7720_MSR,
131 	MOS7720_SPR,
132 	MOS7720_DLL,
133 	MOS7720_DLM,
134 	MOS7720_DPR,		  /* parallel port regs */
135 	MOS7720_DSR,
136 	MOS7720_DCR,
137 	MOS7720_ECR,
138 	MOS7720_SP1_REG,	  /* device control regs */
139 	MOS7720_SP2_REG,	  /* serial port 2 (7720 only) */
140 	MOS7720_PP_REG,
141 	MOS7720_SP_CONTROL_REG,
142 };
143 
144 /*
145  * Return the correct value for the Windex field of the setup packet
146  * for a control endpoint message.  See the 7715 datasheet.
147  */
148 static inline __u16 get_reg_index(enum mos_regs reg)
149 {
150 	static const __u16 mos7715_index_lookup_table[] = {
151 		0x00,		/* MOS7720_THR */
152 		0x00,		/* MOS7720_RHR */
153 		0x01,		/* MOS7720_IER */
154 		0x02,		/* MOS7720_FCR */
155 		0x02,		/* MOS7720_ISR */
156 		0x03,		/* MOS7720_LCR */
157 		0x04,		/* MOS7720_MCR */
158 		0x05,		/* MOS7720_LSR */
159 		0x06,		/* MOS7720_MSR */
160 		0x07,		/* MOS7720_SPR */
161 		0x00,		/* MOS7720_DLL */
162 		0x01,		/* MOS7720_DLM */
163 		0x00,		/* MOS7720_DPR */
164 		0x01,		/* MOS7720_DSR */
165 		0x02,		/* MOS7720_DCR */
166 		0x0a,		/* MOS7720_ECR */
167 		0x01,		/* MOS7720_SP1_REG */
168 		0x02,		/* MOS7720_SP2_REG (7720 only) */
169 		0x04,		/* MOS7720_PP_REG (7715 only) */
170 		0x08,		/* MOS7720_SP_CONTROL_REG */
171 	};
172 	return mos7715_index_lookup_table[reg];
173 }
174 
175 /*
176  * Return the correct value for the upper byte of the Wvalue field of
177  * the setup packet for a control endpoint message.
178  */
179 static inline __u16 get_reg_value(enum mos_regs reg,
180 				  unsigned int serial_portnum)
181 {
182 	if (reg >= MOS7720_SP1_REG)	/* control reg */
183 		return 0x0000;
184 
185 	else if (reg >= MOS7720_DPR)	/* parallel port reg (7715 only) */
186 		return 0x0100;
187 
188 	else			      /* serial port reg */
189 		return (serial_portnum + 2) << 8;
190 }
191 
192 /*
193  * Write data byte to the specified device register.  The data is embedded in
194  * the value field of the setup packet. serial_portnum is ignored for registers
195  * not specific to a particular serial port.
196  */
197 static int write_mos_reg(struct usb_serial *serial, unsigned int serial_portnum,
198 			 enum mos_regs reg, __u8 data)
199 {
200 	struct usb_device *usbdev = serial->dev;
201 	unsigned int pipe = usb_sndctrlpipe(usbdev, 0);
202 	__u8 request = (__u8)0x0e;
203 	__u8 requesttype = (__u8)0x40;
204 	__u16 index = get_reg_index(reg);
205 	__u16 value = get_reg_value(reg, serial_portnum) + data;
206 	int status = usb_control_msg(usbdev, pipe, request, requesttype, value,
207 				     index, NULL, 0, MOS_WDR_TIMEOUT);
208 	if (status < 0)
209 		dev_err(&usbdev->dev,
210 			"mos7720: usb_control_msg() failed: %d\n", status);
211 	return status;
212 }
213 
214 /*
215  * Read data byte from the specified device register.  The data returned by the
216  * device is embedded in the value field of the setup packet.  serial_portnum is
217  * ignored for registers that are not specific to a particular serial port.
218  */
219 static int read_mos_reg(struct usb_serial *serial, unsigned int serial_portnum,
220 			enum mos_regs reg, __u8 *data)
221 {
222 	struct usb_device *usbdev = serial->dev;
223 	unsigned int pipe = usb_rcvctrlpipe(usbdev, 0);
224 	__u8 request = (__u8)0x0d;
225 	__u8 requesttype = (__u8)0xc0;
226 	__u16 index = get_reg_index(reg);
227 	__u16 value = get_reg_value(reg, serial_portnum);
228 	u8 *buf;
229 	int status;
230 
231 	buf = kmalloc(1, GFP_KERNEL);
232 	if (!buf)
233 		return -ENOMEM;
234 
235 	status = usb_control_msg(usbdev, pipe, request, requesttype, value,
236 				     index, buf, 1, MOS_WDR_TIMEOUT);
237 	if (status == 1)
238 		*data = *buf;
239 	else if (status < 0)
240 		dev_err(&usbdev->dev,
241 			"mos7720: usb_control_msg() failed: %d\n", status);
242 	kfree(buf);
243 
244 	return status;
245 }
246 
247 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
248 
249 static inline int mos7715_change_mode(struct mos7715_parport *mos_parport,
250 				      enum mos7715_pp_modes mode)
251 {
252 	mos_parport->shadowECR = mode;
253 	write_mos_reg(mos_parport->serial, dummy, MOS7720_ECR,
254 		      mos_parport->shadowECR);
255 	return 0;
256 }
257 
258 static void destroy_mos_parport(struct kref *kref)
259 {
260 	struct mos7715_parport *mos_parport =
261 		container_of(kref, struct mos7715_parport, ref_count);
262 
263 	kfree(mos_parport);
264 }
265 
266 static void destroy_urbtracker(struct kref *kref)
267 {
268 	struct urbtracker *urbtrack =
269 		container_of(kref, struct urbtracker, ref_count);
270 	struct mos7715_parport *mos_parport = urbtrack->mos_parport;
271 
272 	usb_free_urb(urbtrack->urb);
273 	kfree(urbtrack->setup);
274 	kfree(urbtrack);
275 	kref_put(&mos_parport->ref_count, destroy_mos_parport);
276 }
277 
278 /*
279  * This runs as a tasklet when sending an urb in a non-blocking parallel
280  * port callback had to be deferred because the disconnect mutex could not be
281  * obtained at the time.
282  */
283 static void send_deferred_urbs(unsigned long _mos_parport)
284 {
285 	int ret_val;
286 	unsigned long flags;
287 	struct mos7715_parport *mos_parport = (void *)_mos_parport;
288 	struct urbtracker *urbtrack, *tmp;
289 	struct list_head *cursor, *next;
290 	struct device *dev;
291 
292 	/* if release function ran, game over */
293 	if (unlikely(mos_parport->serial == NULL))
294 		return;
295 
296 	dev = &mos_parport->serial->dev->dev;
297 
298 	/* try again to get the mutex */
299 	if (!mutex_trylock(&mos_parport->serial->disc_mutex)) {
300 		dev_dbg(dev, "%s: rescheduling tasklet\n", __func__);
301 		tasklet_schedule(&mos_parport->urb_tasklet);
302 		return;
303 	}
304 
305 	/* if device disconnected, game over */
306 	if (unlikely(mos_parport->serial->disconnected)) {
307 		mutex_unlock(&mos_parport->serial->disc_mutex);
308 		return;
309 	}
310 
311 	spin_lock_irqsave(&mos_parport->listlock, flags);
312 	if (list_empty(&mos_parport->deferred_urbs)) {
313 		spin_unlock_irqrestore(&mos_parport->listlock, flags);
314 		mutex_unlock(&mos_parport->serial->disc_mutex);
315 		dev_dbg(dev, "%s: deferred_urbs list empty\n", __func__);
316 		return;
317 	}
318 
319 	/* move contents of deferred_urbs list to active_urbs list and submit */
320 	list_for_each_safe(cursor, next, &mos_parport->deferred_urbs)
321 		list_move_tail(cursor, &mos_parport->active_urbs);
322 	list_for_each_entry_safe(urbtrack, tmp, &mos_parport->active_urbs,
323 			    urblist_entry) {
324 		ret_val = usb_submit_urb(urbtrack->urb, GFP_ATOMIC);
325 		dev_dbg(dev, "%s: urb submitted\n", __func__);
326 		if (ret_val) {
327 			dev_err(dev, "usb_submit_urb() failed: %d\n", ret_val);
328 			list_del(&urbtrack->urblist_entry);
329 			kref_put(&urbtrack->ref_count, destroy_urbtracker);
330 		}
331 	}
332 	spin_unlock_irqrestore(&mos_parport->listlock, flags);
333 	mutex_unlock(&mos_parport->serial->disc_mutex);
334 }
335 
336 /* callback for parallel port control urbs submitted asynchronously */
337 static void async_complete(struct urb *urb)
338 {
339 	struct urbtracker *urbtrack = urb->context;
340 	int status = urb->status;
341 
342 	if (unlikely(status))
343 		dev_dbg(&urb->dev->dev, "%s - nonzero urb status received: %d\n", __func__, status);
344 
345 	/* remove the urbtracker from the active_urbs list */
346 	spin_lock(&urbtrack->mos_parport->listlock);
347 	list_del(&urbtrack->urblist_entry);
348 	spin_unlock(&urbtrack->mos_parport->listlock);
349 	kref_put(&urbtrack->ref_count, destroy_urbtracker);
350 }
351 
352 static int write_parport_reg_nonblock(struct mos7715_parport *mos_parport,
353 				      enum mos_regs reg, __u8 data)
354 {
355 	struct urbtracker *urbtrack;
356 	int ret_val;
357 	unsigned long flags;
358 	struct usb_serial *serial = mos_parport->serial;
359 	struct usb_device *usbdev = serial->dev;
360 
361 	/* create and initialize the control urb and containing urbtracker */
362 	urbtrack = kmalloc(sizeof(struct urbtracker), GFP_ATOMIC);
363 	if (!urbtrack)
364 		return -ENOMEM;
365 
366 	kref_get(&mos_parport->ref_count);
367 	urbtrack->mos_parport = mos_parport;
368 	urbtrack->urb = usb_alloc_urb(0, GFP_ATOMIC);
369 	if (!urbtrack->urb) {
370 		kfree(urbtrack);
371 		return -ENOMEM;
372 	}
373 	urbtrack->setup = kmalloc(sizeof(*urbtrack->setup), GFP_ATOMIC);
374 	if (!urbtrack->setup) {
375 		usb_free_urb(urbtrack->urb);
376 		kfree(urbtrack);
377 		return -ENOMEM;
378 	}
379 	urbtrack->setup->bRequestType = (__u8)0x40;
380 	urbtrack->setup->bRequest = (__u8)0x0e;
381 	urbtrack->setup->wValue = cpu_to_le16(get_reg_value(reg, dummy));
382 	urbtrack->setup->wIndex = cpu_to_le16(get_reg_index(reg));
383 	urbtrack->setup->wLength = 0;
384 	usb_fill_control_urb(urbtrack->urb, usbdev,
385 			     usb_sndctrlpipe(usbdev, 0),
386 			     (unsigned char *)urbtrack->setup,
387 			     NULL, 0, async_complete, urbtrack);
388 	kref_init(&urbtrack->ref_count);
389 	INIT_LIST_HEAD(&urbtrack->urblist_entry);
390 
391 	/*
392 	 * get the disconnect mutex, or add tracker to the deferred_urbs list
393 	 * and schedule a tasklet to try again later
394 	 */
395 	if (!mutex_trylock(&serial->disc_mutex)) {
396 		spin_lock_irqsave(&mos_parport->listlock, flags);
397 		list_add_tail(&urbtrack->urblist_entry,
398 			      &mos_parport->deferred_urbs);
399 		spin_unlock_irqrestore(&mos_parport->listlock, flags);
400 		tasklet_schedule(&mos_parport->urb_tasklet);
401 		dev_dbg(&usbdev->dev, "tasklet scheduled\n");
402 		return 0;
403 	}
404 
405 	/* bail if device disconnected */
406 	if (serial->disconnected) {
407 		kref_put(&urbtrack->ref_count, destroy_urbtracker);
408 		mutex_unlock(&serial->disc_mutex);
409 		return -ENODEV;
410 	}
411 
412 	/* add the tracker to the active_urbs list and submit */
413 	spin_lock_irqsave(&mos_parport->listlock, flags);
414 	list_add_tail(&urbtrack->urblist_entry, &mos_parport->active_urbs);
415 	spin_unlock_irqrestore(&mos_parport->listlock, flags);
416 	ret_val = usb_submit_urb(urbtrack->urb, GFP_ATOMIC);
417 	mutex_unlock(&serial->disc_mutex);
418 	if (ret_val) {
419 		dev_err(&usbdev->dev,
420 			"%s: submit_urb() failed: %d\n", __func__, ret_val);
421 		spin_lock_irqsave(&mos_parport->listlock, flags);
422 		list_del(&urbtrack->urblist_entry);
423 		spin_unlock_irqrestore(&mos_parport->listlock, flags);
424 		kref_put(&urbtrack->ref_count, destroy_urbtracker);
425 		return ret_val;
426 	}
427 	return 0;
428 }
429 
430 /*
431  * This is the the common top part of all parallel port callback operations that
432  * send synchronous messages to the device.  This implements convoluted locking
433  * that avoids two scenarios: (1) a port operation is called after usbserial
434  * has called our release function, at which point struct mos7715_parport has
435  * been destroyed, and (2) the device has been disconnected, but usbserial has
436  * not called the release function yet because someone has a serial port open.
437  * The shared release_lock prevents the first, and the mutex and disconnected
438  * flag maintained by usbserial covers the second.  We also use the msg_pending
439  * flag to ensure that all synchronous usb message calls have completed before
440  * our release function can return.
441  */
442 static int parport_prologue(struct parport *pp)
443 {
444 	struct mos7715_parport *mos_parport;
445 
446 	spin_lock(&release_lock);
447 	mos_parport = pp->private_data;
448 	if (unlikely(mos_parport == NULL)) {
449 		/* release fn called, port struct destroyed */
450 		spin_unlock(&release_lock);
451 		return -1;
452 	}
453 	mos_parport->msg_pending = true;   /* synch usb call pending */
454 	reinit_completion(&mos_parport->syncmsg_compl);
455 	spin_unlock(&release_lock);
456 
457 	mutex_lock(&mos_parport->serial->disc_mutex);
458 	if (mos_parport->serial->disconnected) {
459 		/* device disconnected */
460 		mutex_unlock(&mos_parport->serial->disc_mutex);
461 		mos_parport->msg_pending = false;
462 		complete(&mos_parport->syncmsg_compl);
463 		return -1;
464 	}
465 
466 	return 0;
467 }
468 
469 /*
470  * This is the common bottom part of all parallel port functions that send
471  * synchronous messages to the device.
472  */
473 static inline void parport_epilogue(struct parport *pp)
474 {
475 	struct mos7715_parport *mos_parport = pp->private_data;
476 	mutex_unlock(&mos_parport->serial->disc_mutex);
477 	mos_parport->msg_pending = false;
478 	complete(&mos_parport->syncmsg_compl);
479 }
480 
481 static void parport_mos7715_write_data(struct parport *pp, unsigned char d)
482 {
483 	struct mos7715_parport *mos_parport = pp->private_data;
484 
485 	if (parport_prologue(pp) < 0)
486 		return;
487 	mos7715_change_mode(mos_parport, SPP);
488 	write_mos_reg(mos_parport->serial, dummy, MOS7720_DPR, (__u8)d);
489 	parport_epilogue(pp);
490 }
491 
492 static unsigned char parport_mos7715_read_data(struct parport *pp)
493 {
494 	struct mos7715_parport *mos_parport = pp->private_data;
495 	unsigned char d;
496 
497 	if (parport_prologue(pp) < 0)
498 		return 0;
499 	read_mos_reg(mos_parport->serial, dummy, MOS7720_DPR, &d);
500 	parport_epilogue(pp);
501 	return d;
502 }
503 
504 static void parport_mos7715_write_control(struct parport *pp, unsigned char d)
505 {
506 	struct mos7715_parport *mos_parport = pp->private_data;
507 	__u8 data;
508 
509 	if (parport_prologue(pp) < 0)
510 		return;
511 	data = ((__u8)d & 0x0f) | (mos_parport->shadowDCR & 0xf0);
512 	write_mos_reg(mos_parport->serial, dummy, MOS7720_DCR, data);
513 	mos_parport->shadowDCR = data;
514 	parport_epilogue(pp);
515 }
516 
517 static unsigned char parport_mos7715_read_control(struct parport *pp)
518 {
519 	struct mos7715_parport *mos_parport = pp->private_data;
520 	__u8 dcr;
521 
522 	spin_lock(&release_lock);
523 	mos_parport = pp->private_data;
524 	if (unlikely(mos_parport == NULL)) {
525 		spin_unlock(&release_lock);
526 		return 0;
527 	}
528 	dcr = mos_parport->shadowDCR & 0x0f;
529 	spin_unlock(&release_lock);
530 	return dcr;
531 }
532 
533 static unsigned char parport_mos7715_frob_control(struct parport *pp,
534 						  unsigned char mask,
535 						  unsigned char val)
536 {
537 	struct mos7715_parport *mos_parport = pp->private_data;
538 	__u8 dcr;
539 
540 	mask &= 0x0f;
541 	val &= 0x0f;
542 	if (parport_prologue(pp) < 0)
543 		return 0;
544 	mos_parport->shadowDCR = (mos_parport->shadowDCR & (~mask)) ^ val;
545 	write_mos_reg(mos_parport->serial, dummy, MOS7720_DCR,
546 		      mos_parport->shadowDCR);
547 	dcr = mos_parport->shadowDCR & 0x0f;
548 	parport_epilogue(pp);
549 	return dcr;
550 }
551 
552 static unsigned char parport_mos7715_read_status(struct parport *pp)
553 {
554 	unsigned char status;
555 	struct mos7715_parport *mos_parport = pp->private_data;
556 
557 	spin_lock(&release_lock);
558 	mos_parport = pp->private_data;
559 	if (unlikely(mos_parport == NULL)) {	/* release called */
560 		spin_unlock(&release_lock);
561 		return 0;
562 	}
563 	status = atomic_read(&mos_parport->shadowDSR) & 0xf8;
564 	spin_unlock(&release_lock);
565 	return status;
566 }
567 
568 static void parport_mos7715_enable_irq(struct parport *pp)
569 {
570 }
571 
572 static void parport_mos7715_disable_irq(struct parport *pp)
573 {
574 }
575 
576 static void parport_mos7715_data_forward(struct parport *pp)
577 {
578 	struct mos7715_parport *mos_parport = pp->private_data;
579 
580 	if (parport_prologue(pp) < 0)
581 		return;
582 	mos7715_change_mode(mos_parport, PS2);
583 	mos_parport->shadowDCR &=  ~0x20;
584 	write_mos_reg(mos_parport->serial, dummy, MOS7720_DCR,
585 		      mos_parport->shadowDCR);
586 	parport_epilogue(pp);
587 }
588 
589 static void parport_mos7715_data_reverse(struct parport *pp)
590 {
591 	struct mos7715_parport *mos_parport = pp->private_data;
592 
593 	if (parport_prologue(pp) < 0)
594 		return;
595 	mos7715_change_mode(mos_parport, PS2);
596 	mos_parport->shadowDCR |= 0x20;
597 	write_mos_reg(mos_parport->serial, dummy, MOS7720_DCR,
598 		      mos_parport->shadowDCR);
599 	parport_epilogue(pp);
600 }
601 
602 static void parport_mos7715_init_state(struct pardevice *dev,
603 				       struct parport_state *s)
604 {
605 	s->u.pc.ctr = DCR_INIT_VAL;
606 	s->u.pc.ecr = ECR_INIT_VAL;
607 }
608 
609 /* N.B. Parport core code requires that this function not block */
610 static void parport_mos7715_save_state(struct parport *pp,
611 				       struct parport_state *s)
612 {
613 	struct mos7715_parport *mos_parport;
614 
615 	spin_lock(&release_lock);
616 	mos_parport = pp->private_data;
617 	if (unlikely(mos_parport == NULL)) {	/* release called */
618 		spin_unlock(&release_lock);
619 		return;
620 	}
621 	s->u.pc.ctr = mos_parport->shadowDCR;
622 	s->u.pc.ecr = mos_parport->shadowECR;
623 	spin_unlock(&release_lock);
624 }
625 
626 /* N.B. Parport core code requires that this function not block */
627 static void parport_mos7715_restore_state(struct parport *pp,
628 					  struct parport_state *s)
629 {
630 	struct mos7715_parport *mos_parport;
631 
632 	spin_lock(&release_lock);
633 	mos_parport = pp->private_data;
634 	if (unlikely(mos_parport == NULL)) {	/* release called */
635 		spin_unlock(&release_lock);
636 		return;
637 	}
638 	write_parport_reg_nonblock(mos_parport, MOS7720_DCR,
639 				   mos_parport->shadowDCR);
640 	write_parport_reg_nonblock(mos_parport, MOS7720_ECR,
641 				   mos_parport->shadowECR);
642 	spin_unlock(&release_lock);
643 }
644 
645 static size_t parport_mos7715_write_compat(struct parport *pp,
646 					   const void *buffer,
647 					   size_t len, int flags)
648 {
649 	int retval;
650 	struct mos7715_parport *mos_parport = pp->private_data;
651 	int actual_len;
652 
653 	if (parport_prologue(pp) < 0)
654 		return 0;
655 	mos7715_change_mode(mos_parport, PPF);
656 	retval = usb_bulk_msg(mos_parport->serial->dev,
657 			      usb_sndbulkpipe(mos_parport->serial->dev, 2),
658 			      (void *)buffer, len, &actual_len,
659 			      MOS_WDR_TIMEOUT);
660 	parport_epilogue(pp);
661 	if (retval) {
662 		dev_err(&mos_parport->serial->dev->dev,
663 			"mos7720: usb_bulk_msg() failed: %d\n", retval);
664 		return 0;
665 	}
666 	return actual_len;
667 }
668 
669 static struct parport_operations parport_mos7715_ops = {
670 	.owner =		THIS_MODULE,
671 	.write_data =		parport_mos7715_write_data,
672 	.read_data =		parport_mos7715_read_data,
673 
674 	.write_control =	parport_mos7715_write_control,
675 	.read_control =		parport_mos7715_read_control,
676 	.frob_control =		parport_mos7715_frob_control,
677 
678 	.read_status =		parport_mos7715_read_status,
679 
680 	.enable_irq =		parport_mos7715_enable_irq,
681 	.disable_irq =		parport_mos7715_disable_irq,
682 
683 	.data_forward =		parport_mos7715_data_forward,
684 	.data_reverse =		parport_mos7715_data_reverse,
685 
686 	.init_state =		parport_mos7715_init_state,
687 	.save_state =		parport_mos7715_save_state,
688 	.restore_state =	parport_mos7715_restore_state,
689 
690 	.compat_write_data =	parport_mos7715_write_compat,
691 
692 	.nibble_read_data =	parport_ieee1284_read_nibble,
693 	.byte_read_data =	parport_ieee1284_read_byte,
694 };
695 
696 /*
697  * Allocate and initialize parallel port control struct, initialize
698  * the parallel port hardware device, and register with the parport subsystem.
699  */
700 static int mos7715_parport_init(struct usb_serial *serial)
701 {
702 	struct mos7715_parport *mos_parport;
703 
704 	/* allocate and initialize parallel port control struct */
705 	mos_parport = kzalloc(sizeof(struct mos7715_parport), GFP_KERNEL);
706 	if (!mos_parport)
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, MOS7720_PP_REG, (__u8)0x80);
722 	write_mos_reg(mos_parport->serial, dummy, MOS7720_PP_REG, (__u8)0x00);
723 
724 	/* initialize device registers */
725 	mos_parport->shadowDCR = DCR_INIT_VAL;
726 	write_mos_reg(mos_parport->serial, dummy, MOS7720_DCR,
727 		      mos_parport->shadowDCR);
728 	mos_parport->shadowECR = ECR_INIT_VAL;
729 	write_mos_reg(mos_parport->serial, dummy, MOS7720_ECR,
730 		      mos_parport->shadowECR);
731 
732 	/* register with parport core */
733 	mos_parport->pp = parport_register_port(0, PARPORT_IRQ_NONE,
734 						PARPORT_DMA_NONE,
735 						&parport_mos7715_ops);
736 	if (mos_parport->pp == NULL) {
737 		dev_err(&serial->interface->dev,
738 			"Could not register parport\n");
739 		kref_put(&mos_parport->ref_count, destroy_mos_parport);
740 		return -EIO;
741 	}
742 	mos_parport->pp->private_data = mos_parport;
743 	mos_parport->pp->modes = PARPORT_MODE_COMPAT | PARPORT_MODE_PCSPP;
744 	mos_parport->pp->dev = &serial->interface->dev;
745 	parport_announce_port(mos_parport->pp);
746 
747 	return 0;
748 }
749 #endif	/* CONFIG_USB_SERIAL_MOS7715_PARPORT */
750 
751 /*
752  * mos7720_interrupt_callback
753  *	this is the callback function for when we have received data on the
754  *	interrupt endpoint.
755  */
756 static void mos7720_interrupt_callback(struct urb *urb)
757 {
758 	int result;
759 	int length;
760 	int status = urb->status;
761 	struct device *dev = &urb->dev->dev;
762 	__u8 *data;
763 	__u8 sp1;
764 	__u8 sp2;
765 
766 	switch (status) {
767 	case 0:
768 		/* success */
769 		break;
770 	case -ECONNRESET:
771 	case -ENOENT:
772 	case -ESHUTDOWN:
773 		/* this urb is terminated, clean up */
774 		dev_dbg(dev, "%s - urb shutting down with status: %d\n", __func__, status);
775 		return;
776 	default:
777 		dev_dbg(dev, "%s - nonzero urb status received: %d\n", __func__, status);
778 		goto exit;
779 	}
780 
781 	length = urb->actual_length;
782 	data = urb->transfer_buffer;
783 
784 	/* Moschip get 4 bytes
785 	 * Byte 1 IIR Port 1 (port.number is 0)
786 	 * Byte 2 IIR Port 2 (port.number is 1)
787 	 * Byte 3 --------------
788 	 * Byte 4 FIFO status for both */
789 
790 	/* the above description is inverted
791 	 * 	oneukum 2007-03-14 */
792 
793 	if (unlikely(length != 4)) {
794 		dev_dbg(dev, "Wrong data !!!\n");
795 		return;
796 	}
797 
798 	sp1 = data[3];
799 	sp2 = data[2];
800 
801 	if ((sp1 | sp2) & 0x01) {
802 		/* No Interrupt Pending in both the ports */
803 		dev_dbg(dev, "No Interrupt !!!\n");
804 	} else {
805 		switch (sp1 & 0x0f) {
806 		case SERIAL_IIR_RLS:
807 			dev_dbg(dev, "Serial Port 1: Receiver status error or address bit detected in 9-bit mode\n");
808 			break;
809 		case SERIAL_IIR_CTI:
810 			dev_dbg(dev, "Serial Port 1: Receiver time out\n");
811 			break;
812 		case SERIAL_IIR_MS:
813 			/* dev_dbg(dev, "Serial Port 1: Modem status change\n"); */
814 			break;
815 		}
816 
817 		switch (sp2 & 0x0f) {
818 		case SERIAL_IIR_RLS:
819 			dev_dbg(dev, "Serial Port 2: Receiver status error or address bit detected in 9-bit mode\n");
820 			break;
821 		case SERIAL_IIR_CTI:
822 			dev_dbg(dev, "Serial Port 2: Receiver time out\n");
823 			break;
824 		case SERIAL_IIR_MS:
825 			/* dev_dbg(dev, "Serial Port 2: Modem status change\n"); */
826 			break;
827 		}
828 	}
829 
830 exit:
831 	result = usb_submit_urb(urb, GFP_ATOMIC);
832 	if (result)
833 		dev_err(dev, "%s - Error %d submitting control urb\n", __func__, result);
834 }
835 
836 /*
837  * mos7715_interrupt_callback
838  *	this is the 7715's callback function for when we have received data on
839  *	the interrupt endpoint.
840  */
841 static void mos7715_interrupt_callback(struct urb *urb)
842 {
843 	int result;
844 	int length;
845 	int status = urb->status;
846 	struct device *dev = &urb->dev->dev;
847 	__u8 *data;
848 	__u8 iir;
849 
850 	switch (status) {
851 	case 0:
852 		/* success */
853 		break;
854 	case -ECONNRESET:
855 	case -ENOENT:
856 	case -ESHUTDOWN:
857 	case -ENODEV:
858 		/* this urb is terminated, clean up */
859 		dev_dbg(dev, "%s - urb shutting down with status: %d\n", __func__, status);
860 		return;
861 	default:
862 		dev_dbg(dev, "%s - nonzero urb status received: %d\n", __func__, status);
863 		goto exit;
864 	}
865 
866 	length = urb->actual_length;
867 	data = urb->transfer_buffer;
868 
869 	/* Structure of data from 7715 device:
870 	 * Byte 1: IIR serial Port
871 	 * Byte 2: unused
872 	 * Byte 2: DSR parallel port
873 	 * Byte 4: FIFO status for both */
874 
875 	if (unlikely(length != 4)) {
876 		dev_dbg(dev, "Wrong data !!!\n");
877 		return;
878 	}
879 
880 	iir = data[0];
881 	if (!(iir & 0x01)) {	/* serial port interrupt pending */
882 		switch (iir & 0x0f) {
883 		case SERIAL_IIR_RLS:
884 			dev_dbg(dev, "Serial Port: Receiver status error or address bit detected in 9-bit mode\n");
885 			break;
886 		case SERIAL_IIR_CTI:
887 			dev_dbg(dev, "Serial Port: Receiver time out\n");
888 			break;
889 		case SERIAL_IIR_MS:
890 			/* dev_dbg(dev, "Serial Port: Modem status change\n"); */
891 			break;
892 		}
893 	}
894 
895 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
896 	{       /* update local copy of DSR reg */
897 		struct usb_serial_port *port = urb->context;
898 		struct mos7715_parport *mos_parport = port->serial->private;
899 		if (unlikely(mos_parport == NULL))
900 			return;
901 		atomic_set(&mos_parport->shadowDSR, data[2]);
902 	}
903 #endif
904 
905 exit:
906 	result = usb_submit_urb(urb, GFP_ATOMIC);
907 	if (result)
908 		dev_err(dev, "%s - Error %d submitting control urb\n", __func__, result);
909 }
910 
911 /*
912  * mos7720_bulk_in_callback
913  *	this is the callback function for when we have received data on the
914  *	bulk in endpoint.
915  */
916 static void mos7720_bulk_in_callback(struct urb *urb)
917 {
918 	int retval;
919 	unsigned char *data ;
920 	struct usb_serial_port *port;
921 	int status = urb->status;
922 
923 	if (status) {
924 		dev_dbg(&urb->dev->dev, "nonzero read bulk status received: %d\n", status);
925 		return;
926 	}
927 
928 	port = urb->context;
929 
930 	dev_dbg(&port->dev, "Entering...%s\n", __func__);
931 
932 	data = urb->transfer_buffer;
933 
934 	if (urb->actual_length) {
935 		tty_insert_flip_string(&port->port, data, urb->actual_length);
936 		tty_flip_buffer_push(&port->port);
937 	}
938 
939 	if (port->read_urb->status != -EINPROGRESS) {
940 		retval = usb_submit_urb(port->read_urb, GFP_ATOMIC);
941 		if (retval)
942 			dev_dbg(&port->dev, "usb_submit_urb(read bulk) failed, retval = %d\n", retval);
943 	}
944 }
945 
946 /*
947  * mos7720_bulk_out_data_callback
948  *	this is the callback function for when we have finished sending serial
949  *	data on the bulk out endpoint.
950  */
951 static void mos7720_bulk_out_data_callback(struct urb *urb)
952 {
953 	struct moschip_port *mos7720_port;
954 	int status = urb->status;
955 
956 	if (status) {
957 		dev_dbg(&urb->dev->dev, "nonzero write bulk status received:%d\n", status);
958 		return;
959 	}
960 
961 	mos7720_port = urb->context;
962 	if (!mos7720_port) {
963 		dev_dbg(&urb->dev->dev, "NULL mos7720_port pointer\n");
964 		return ;
965 	}
966 
967 	if (mos7720_port->open)
968 		tty_port_tty_wakeup(&mos7720_port->port->port);
969 }
970 
971 static int mos77xx_calc_num_ports(struct usb_serial *serial)
972 {
973 	u16 product = le16_to_cpu(serial->dev->descriptor.idProduct);
974 	if (product == MOSCHIP_DEVICE_ID_7715)
975 		return 1;
976 
977 	return 2;
978 }
979 
980 static int mos7720_open(struct tty_struct *tty, struct usb_serial_port *port)
981 {
982 	struct usb_serial *serial;
983 	struct urb *urb;
984 	struct moschip_port *mos7720_port;
985 	int response;
986 	int port_number;
987 	__u8 data;
988 	int allocated_urbs = 0;
989 	int j;
990 
991 	serial = port->serial;
992 
993 	mos7720_port = usb_get_serial_port_data(port);
994 	if (mos7720_port == NULL)
995 		return -ENODEV;
996 
997 	usb_clear_halt(serial->dev, port->write_urb->pipe);
998 	usb_clear_halt(serial->dev, port->read_urb->pipe);
999 
1000 	/* Initialising the write urb pool */
1001 	for (j = 0; j < NUM_URBS; ++j) {
1002 		urb = usb_alloc_urb(0, GFP_KERNEL);
1003 		mos7720_port->write_urb_pool[j] = urb;
1004 		if (!urb)
1005 			continue;
1006 
1007 		urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE,
1008 					       GFP_KERNEL);
1009 		if (!urb->transfer_buffer) {
1010 			usb_free_urb(mos7720_port->write_urb_pool[j]);
1011 			mos7720_port->write_urb_pool[j] = NULL;
1012 			continue;
1013 		}
1014 		allocated_urbs++;
1015 	}
1016 
1017 	if (!allocated_urbs)
1018 		return -ENOMEM;
1019 
1020 	 /* Initialize MCS7720 -- Write Init values to corresponding Registers
1021 	  *
1022 	  * Register Index
1023 	  * 0 : MOS7720_THR/MOS7720_RHR
1024 	  * 1 : MOS7720_IER
1025 	  * 2 : MOS7720_FCR
1026 	  * 3 : MOS7720_LCR
1027 	  * 4 : MOS7720_MCR
1028 	  * 5 : MOS7720_LSR
1029 	  * 6 : MOS7720_MSR
1030 	  * 7 : MOS7720_SPR
1031 	  *
1032 	  * 0x08 : SP1/2 Control Reg
1033 	  */
1034 	port_number = port->port_number;
1035 	read_mos_reg(serial, port_number, MOS7720_LSR, &data);
1036 
1037 	dev_dbg(&port->dev, "SS::%p LSR:%x\n", mos7720_port, data);
1038 
1039 	write_mos_reg(serial, dummy, MOS7720_SP1_REG, 0x02);
1040 	write_mos_reg(serial, dummy, MOS7720_SP2_REG, 0x02);
1041 
1042 	write_mos_reg(serial, port_number, MOS7720_IER, 0x00);
1043 	write_mos_reg(serial, port_number, MOS7720_FCR, 0x00);
1044 
1045 	write_mos_reg(serial, port_number, MOS7720_FCR, 0xcf);
1046 	mos7720_port->shadowLCR = 0x03;
1047 	write_mos_reg(serial, port_number, MOS7720_LCR,
1048 		      mos7720_port->shadowLCR);
1049 	mos7720_port->shadowMCR = 0x0b;
1050 	write_mos_reg(serial, port_number, MOS7720_MCR,
1051 		      mos7720_port->shadowMCR);
1052 
1053 	write_mos_reg(serial, port_number, MOS7720_SP_CONTROL_REG, 0x00);
1054 	read_mos_reg(serial, dummy, MOS7720_SP_CONTROL_REG, &data);
1055 	data = data | (port->port_number + 1);
1056 	write_mos_reg(serial, dummy, MOS7720_SP_CONTROL_REG, data);
1057 	mos7720_port->shadowLCR = 0x83;
1058 	write_mos_reg(serial, port_number, MOS7720_LCR,
1059 		      mos7720_port->shadowLCR);
1060 	write_mos_reg(serial, port_number, MOS7720_THR, 0x0c);
1061 	write_mos_reg(serial, port_number, MOS7720_IER, 0x00);
1062 	mos7720_port->shadowLCR = 0x03;
1063 	write_mos_reg(serial, port_number, MOS7720_LCR,
1064 		      mos7720_port->shadowLCR);
1065 	write_mos_reg(serial, port_number, MOS7720_IER, 0x0c);
1066 
1067 	response = usb_submit_urb(port->read_urb, GFP_KERNEL);
1068 	if (response)
1069 		dev_err(&port->dev, "%s - Error %d submitting read urb\n",
1070 							__func__, response);
1071 
1072 	/* initialize our port settings */
1073 	mos7720_port->shadowMCR = UART_MCR_OUT2; /* Must set to enable ints! */
1074 
1075 	/* send a open port command */
1076 	mos7720_port->open = 1;
1077 
1078 	return 0;
1079 }
1080 
1081 /*
1082  * mos7720_chars_in_buffer
1083  *	this function is called by the tty driver when it wants to know how many
1084  *	bytes of data we currently have outstanding in the port (data that has
1085  *	been written, but hasn't made it out the port yet)
1086  *	If successful, we return the number of bytes left to be written in the
1087  *	system,
1088  *	Otherwise we return a negative error number.
1089  */
1090 static int mos7720_chars_in_buffer(struct tty_struct *tty)
1091 {
1092 	struct usb_serial_port *port = tty->driver_data;
1093 	int i;
1094 	int chars = 0;
1095 	struct moschip_port *mos7720_port;
1096 
1097 	mos7720_port = usb_get_serial_port_data(port);
1098 	if (mos7720_port == NULL)
1099 		return 0;
1100 
1101 	for (i = 0; i < NUM_URBS; ++i) {
1102 		if (mos7720_port->write_urb_pool[i] &&
1103 		    mos7720_port->write_urb_pool[i]->status == -EINPROGRESS)
1104 			chars += URB_TRANSFER_BUFFER_SIZE;
1105 	}
1106 	dev_dbg(&port->dev, "%s - returns %d\n", __func__, chars);
1107 	return chars;
1108 }
1109 
1110 static void mos7720_close(struct usb_serial_port *port)
1111 {
1112 	struct usb_serial *serial;
1113 	struct moschip_port *mos7720_port;
1114 	int j;
1115 
1116 	serial = port->serial;
1117 
1118 	mos7720_port = usb_get_serial_port_data(port);
1119 	if (mos7720_port == NULL)
1120 		return;
1121 
1122 	for (j = 0; j < NUM_URBS; ++j)
1123 		usb_kill_urb(mos7720_port->write_urb_pool[j]);
1124 
1125 	/* Freeing Write URBs */
1126 	for (j = 0; j < NUM_URBS; ++j) {
1127 		if (mos7720_port->write_urb_pool[j]) {
1128 			kfree(mos7720_port->write_urb_pool[j]->transfer_buffer);
1129 			usb_free_urb(mos7720_port->write_urb_pool[j]);
1130 		}
1131 	}
1132 
1133 	/* While closing port, shutdown all bulk read, write  *
1134 	 * and interrupt read if they exists, otherwise nop   */
1135 	usb_kill_urb(port->write_urb);
1136 	usb_kill_urb(port->read_urb);
1137 
1138 	write_mos_reg(serial, port->port_number, MOS7720_MCR, 0x00);
1139 	write_mos_reg(serial, port->port_number, MOS7720_IER, 0x00);
1140 
1141 	mos7720_port->open = 0;
1142 }
1143 
1144 static void mos7720_break(struct tty_struct *tty, int break_state)
1145 {
1146 	struct usb_serial_port *port = tty->driver_data;
1147 	unsigned char data;
1148 	struct usb_serial *serial;
1149 	struct moschip_port *mos7720_port;
1150 
1151 	serial = port->serial;
1152 
1153 	mos7720_port = usb_get_serial_port_data(port);
1154 	if (mos7720_port == NULL)
1155 		return;
1156 
1157 	if (break_state == -1)
1158 		data = mos7720_port->shadowLCR | UART_LCR_SBC;
1159 	else
1160 		data = mos7720_port->shadowLCR & ~UART_LCR_SBC;
1161 
1162 	mos7720_port->shadowLCR  = data;
1163 	write_mos_reg(serial, port->port_number, MOS7720_LCR,
1164 		      mos7720_port->shadowLCR);
1165 }
1166 
1167 /*
1168  * mos7720_write_room
1169  *	this function is called by the tty driver when it wants to know how many
1170  *	bytes of data we can accept for a specific port.
1171  *	If successful, we return the amount of room that we have for this port
1172  *	Otherwise we return a negative error number.
1173  */
1174 static int mos7720_write_room(struct tty_struct *tty)
1175 {
1176 	struct usb_serial_port *port = tty->driver_data;
1177 	struct moschip_port *mos7720_port;
1178 	int room = 0;
1179 	int i;
1180 
1181 	mos7720_port = usb_get_serial_port_data(port);
1182 	if (mos7720_port == NULL)
1183 		return -ENODEV;
1184 
1185 	/* FIXME: Locking */
1186 	for (i = 0; i < NUM_URBS; ++i) {
1187 		if (mos7720_port->write_urb_pool[i] &&
1188 		    mos7720_port->write_urb_pool[i]->status != -EINPROGRESS)
1189 			room += URB_TRANSFER_BUFFER_SIZE;
1190 	}
1191 
1192 	dev_dbg(&port->dev, "%s - returns %d\n", __func__, room);
1193 	return room;
1194 }
1195 
1196 static int mos7720_write(struct tty_struct *tty, struct usb_serial_port *port,
1197 				 const unsigned char *data, int count)
1198 {
1199 	int status;
1200 	int i;
1201 	int bytes_sent = 0;
1202 	int transfer_size;
1203 
1204 	struct moschip_port *mos7720_port;
1205 	struct usb_serial *serial;
1206 	struct urb    *urb;
1207 	const unsigned char *current_position = data;
1208 
1209 	serial = port->serial;
1210 
1211 	mos7720_port = usb_get_serial_port_data(port);
1212 	if (mos7720_port == NULL)
1213 		return -ENODEV;
1214 
1215 	/* try to find a free urb in the list */
1216 	urb = NULL;
1217 
1218 	for (i = 0; i < NUM_URBS; ++i) {
1219 		if (mos7720_port->write_urb_pool[i] &&
1220 		    mos7720_port->write_urb_pool[i]->status != -EINPROGRESS) {
1221 			urb = mos7720_port->write_urb_pool[i];
1222 			dev_dbg(&port->dev, "URB:%d\n", i);
1223 			break;
1224 		}
1225 	}
1226 
1227 	if (urb == NULL) {
1228 		dev_dbg(&port->dev, "%s - no more free urbs\n", __func__);
1229 		goto exit;
1230 	}
1231 
1232 	if (urb->transfer_buffer == NULL) {
1233 		urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE,
1234 					       GFP_ATOMIC);
1235 		if (!urb->transfer_buffer)
1236 			goto exit;
1237 	}
1238 	transfer_size = min(count, URB_TRANSFER_BUFFER_SIZE);
1239 
1240 	memcpy(urb->transfer_buffer, current_position, transfer_size);
1241 	usb_serial_debug_data(&port->dev, __func__, transfer_size,
1242 			      urb->transfer_buffer);
1243 
1244 	/* fill urb with data and submit  */
1245 	usb_fill_bulk_urb(urb, serial->dev,
1246 			  usb_sndbulkpipe(serial->dev,
1247 					port->bulk_out_endpointAddress),
1248 			  urb->transfer_buffer, transfer_size,
1249 			  mos7720_bulk_out_data_callback, mos7720_port);
1250 
1251 	/* send it down the pipe */
1252 	status = usb_submit_urb(urb, GFP_ATOMIC);
1253 	if (status) {
1254 		dev_err_console(port, "%s - usb_submit_urb(write bulk) failed "
1255 			"with status = %d\n", __func__, status);
1256 		bytes_sent = status;
1257 		goto exit;
1258 	}
1259 	bytes_sent = transfer_size;
1260 
1261 exit:
1262 	return bytes_sent;
1263 }
1264 
1265 static void mos7720_throttle(struct tty_struct *tty)
1266 {
1267 	struct usb_serial_port *port = tty->driver_data;
1268 	struct moschip_port *mos7720_port;
1269 	int status;
1270 
1271 	mos7720_port = usb_get_serial_port_data(port);
1272 
1273 	if (mos7720_port == NULL)
1274 		return;
1275 
1276 	if (!mos7720_port->open) {
1277 		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
1278 		return;
1279 	}
1280 
1281 	/* if we are implementing XON/XOFF, send the stop character */
1282 	if (I_IXOFF(tty)) {
1283 		unsigned char stop_char = STOP_CHAR(tty);
1284 		status = mos7720_write(tty, port, &stop_char, 1);
1285 		if (status <= 0)
1286 			return;
1287 	}
1288 
1289 	/* if we are implementing RTS/CTS, toggle that line */
1290 	if (C_CRTSCTS(tty)) {
1291 		mos7720_port->shadowMCR &= ~UART_MCR_RTS;
1292 		write_mos_reg(port->serial, port->port_number, MOS7720_MCR,
1293 			      mos7720_port->shadowMCR);
1294 	}
1295 }
1296 
1297 static void mos7720_unthrottle(struct tty_struct *tty)
1298 {
1299 	struct usb_serial_port *port = tty->driver_data;
1300 	struct moschip_port *mos7720_port = usb_get_serial_port_data(port);
1301 	int status;
1302 
1303 	if (mos7720_port == NULL)
1304 		return;
1305 
1306 	if (!mos7720_port->open) {
1307 		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
1308 		return;
1309 	}
1310 
1311 	/* if we are implementing XON/XOFF, send the start character */
1312 	if (I_IXOFF(tty)) {
1313 		unsigned char start_char = START_CHAR(tty);
1314 		status = mos7720_write(tty, port, &start_char, 1);
1315 		if (status <= 0)
1316 			return;
1317 	}
1318 
1319 	/* if we are implementing RTS/CTS, toggle that line */
1320 	if (C_CRTSCTS(tty)) {
1321 		mos7720_port->shadowMCR |= UART_MCR_RTS;
1322 		write_mos_reg(port->serial, port->port_number, MOS7720_MCR,
1323 			      mos7720_port->shadowMCR);
1324 	}
1325 }
1326 
1327 /* FIXME: this function does not work */
1328 static int set_higher_rates(struct moschip_port *mos7720_port,
1329 			    unsigned int baud)
1330 {
1331 	struct usb_serial_port *port;
1332 	struct usb_serial *serial;
1333 	int port_number;
1334 	enum mos_regs sp_reg;
1335 	if (mos7720_port == NULL)
1336 		return -EINVAL;
1337 
1338 	port = mos7720_port->port;
1339 	serial = port->serial;
1340 
1341 	 /***********************************************
1342 	 *      Init Sequence for higher rates
1343 	 ***********************************************/
1344 	dev_dbg(&port->dev, "Sending Setting Commands ..........\n");
1345 	port_number = port->port_number;
1346 
1347 	write_mos_reg(serial, port_number, MOS7720_IER, 0x00);
1348 	write_mos_reg(serial, port_number, MOS7720_FCR, 0x00);
1349 	write_mos_reg(serial, port_number, MOS7720_FCR, 0xcf);
1350 	mos7720_port->shadowMCR = 0x0b;
1351 	write_mos_reg(serial, port_number, MOS7720_MCR,
1352 		      mos7720_port->shadowMCR);
1353 	write_mos_reg(serial, dummy, MOS7720_SP_CONTROL_REG, 0x00);
1354 
1355 	/***********************************************
1356 	 *              Set for higher rates           *
1357 	 ***********************************************/
1358 	/* writing baud rate verbatum into uart clock field clearly not right */
1359 	if (port_number == 0)
1360 		sp_reg = MOS7720_SP1_REG;
1361 	else
1362 		sp_reg = MOS7720_SP2_REG;
1363 	write_mos_reg(serial, dummy, sp_reg, baud * 0x10);
1364 	write_mos_reg(serial, dummy, MOS7720_SP_CONTROL_REG, 0x03);
1365 	mos7720_port->shadowMCR = 0x2b;
1366 	write_mos_reg(serial, port_number, MOS7720_MCR,
1367 		      mos7720_port->shadowMCR);
1368 
1369 	/***********************************************
1370 	 *              Set DLL/DLM
1371 	 ***********************************************/
1372 	mos7720_port->shadowLCR = mos7720_port->shadowLCR | UART_LCR_DLAB;
1373 	write_mos_reg(serial, port_number, MOS7720_LCR,
1374 		      mos7720_port->shadowLCR);
1375 	write_mos_reg(serial, port_number, MOS7720_DLL, 0x01);
1376 	write_mos_reg(serial, port_number, MOS7720_DLM, 0x00);
1377 	mos7720_port->shadowLCR = mos7720_port->shadowLCR & ~UART_LCR_DLAB;
1378 	write_mos_reg(serial, port_number, MOS7720_LCR,
1379 		      mos7720_port->shadowLCR);
1380 
1381 	return 0;
1382 }
1383 
1384 /* baud rate information */
1385 struct divisor_table_entry {
1386 	__u32  baudrate;
1387 	__u16  divisor;
1388 };
1389 
1390 /* Define table of divisors for moschip 7720 hardware	   *
1391  * These assume a 3.6864MHz crystal, the standard /16, and *
1392  * MCR.7 = 0.						   */
1393 static struct divisor_table_entry divisor_table[] = {
1394 	{   50,		2304},
1395 	{   110,	1047},	/* 2094.545455 => 230450   => .0217 % over */
1396 	{   134,	857},	/* 1713.011152 => 230398.5 => .00065% under */
1397 	{   150,	768},
1398 	{   300,	384},
1399 	{   600,	192},
1400 	{   1200,	96},
1401 	{   1800,	64},
1402 	{   2400,	48},
1403 	{   4800,	24},
1404 	{   7200,	16},
1405 	{   9600,	12},
1406 	{   19200,	6},
1407 	{   38400,	3},
1408 	{   57600,	2},
1409 	{   115200,	1},
1410 };
1411 
1412 /*****************************************************************************
1413  * calc_baud_rate_divisor
1414  *	this function calculates the proper baud rate divisor for the specified
1415  *	baud rate.
1416  *****************************************************************************/
1417 static int calc_baud_rate_divisor(struct usb_serial_port *port, int baudrate, int *divisor)
1418 {
1419 	int i;
1420 	__u16 custom;
1421 	__u16 round1;
1422 	__u16 round;
1423 
1424 
1425 	dev_dbg(&port->dev, "%s - %d\n", __func__, baudrate);
1426 
1427 	for (i = 0; i < ARRAY_SIZE(divisor_table); i++) {
1428 		if (divisor_table[i].baudrate == baudrate) {
1429 			*divisor = divisor_table[i].divisor;
1430 			return 0;
1431 		}
1432 	}
1433 
1434 	/* After trying for all the standard baud rates    *
1435 	 * Try calculating the divisor for this baud rate  */
1436 	if (baudrate > 75 &&  baudrate < 230400) {
1437 		/* get the divisor */
1438 		custom = (__u16)(230400L  / baudrate);
1439 
1440 		/* Check for round off */
1441 		round1 = (__u16)(2304000L / baudrate);
1442 		round = (__u16)(round1 - (custom * 10));
1443 		if (round > 4)
1444 			custom++;
1445 		*divisor = custom;
1446 
1447 		dev_dbg(&port->dev, "Baud %d = %d\n", baudrate, custom);
1448 		return 0;
1449 	}
1450 
1451 	dev_dbg(&port->dev, "Baud calculation Failed...\n");
1452 	return -EINVAL;
1453 }
1454 
1455 /*
1456  * send_cmd_write_baud_rate
1457  *	this function sends the proper command to change the baud rate of the
1458  *	specified port.
1459  */
1460 static int send_cmd_write_baud_rate(struct moschip_port *mos7720_port,
1461 				    int baudrate)
1462 {
1463 	struct usb_serial_port *port;
1464 	struct usb_serial *serial;
1465 	int divisor;
1466 	int status;
1467 	unsigned char number;
1468 
1469 	if (mos7720_port == NULL)
1470 		return -1;
1471 
1472 	port = mos7720_port->port;
1473 	serial = port->serial;
1474 
1475 	number = port->port_number;
1476 	dev_dbg(&port->dev, "%s - baud = %d\n", __func__, baudrate);
1477 
1478 	/* Calculate the Divisor */
1479 	status = calc_baud_rate_divisor(port, baudrate, &divisor);
1480 	if (status) {
1481 		dev_err(&port->dev, "%s - bad baud rate\n", __func__);
1482 		return status;
1483 	}
1484 
1485 	/* Enable access to divisor latch */
1486 	mos7720_port->shadowLCR = mos7720_port->shadowLCR | UART_LCR_DLAB;
1487 	write_mos_reg(serial, number, MOS7720_LCR, mos7720_port->shadowLCR);
1488 
1489 	/* Write the divisor */
1490 	write_mos_reg(serial, number, MOS7720_DLL, (__u8)(divisor & 0xff));
1491 	write_mos_reg(serial, number, MOS7720_DLM,
1492 		      (__u8)((divisor & 0xff00) >> 8));
1493 
1494 	/* Disable access to divisor latch */
1495 	mos7720_port->shadowLCR = mos7720_port->shadowLCR & ~UART_LCR_DLAB;
1496 	write_mos_reg(serial, number, MOS7720_LCR, mos7720_port->shadowLCR);
1497 
1498 	return status;
1499 }
1500 
1501 /*
1502  * change_port_settings
1503  *	This routine is called to set the UART on the device to match
1504  *      the specified new settings.
1505  */
1506 static void change_port_settings(struct tty_struct *tty,
1507 				 struct moschip_port *mos7720_port,
1508 				 struct ktermios *old_termios)
1509 {
1510 	struct usb_serial_port *port;
1511 	struct usb_serial *serial;
1512 	int baud;
1513 	unsigned cflag;
1514 	unsigned iflag;
1515 	__u8 mask = 0xff;
1516 	__u8 lData;
1517 	__u8 lParity;
1518 	__u8 lStop;
1519 	int status;
1520 	int port_number;
1521 
1522 	if (mos7720_port == NULL)
1523 		return ;
1524 
1525 	port = mos7720_port->port;
1526 	serial = port->serial;
1527 	port_number = port->port_number;
1528 
1529 	if (!mos7720_port->open) {
1530 		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
1531 		return;
1532 	}
1533 
1534 	lData = UART_LCR_WLEN8;
1535 	lStop = 0x00;	/* 1 stop bit */
1536 	lParity = 0x00;	/* No parity */
1537 
1538 	cflag = tty->termios.c_cflag;
1539 	iflag = tty->termios.c_iflag;
1540 
1541 	/* Change the number of bits */
1542 	switch (cflag & CSIZE) {
1543 	case CS5:
1544 		lData = UART_LCR_WLEN5;
1545 		mask = 0x1f;
1546 		break;
1547 
1548 	case CS6:
1549 		lData = UART_LCR_WLEN6;
1550 		mask = 0x3f;
1551 		break;
1552 
1553 	case CS7:
1554 		lData = UART_LCR_WLEN7;
1555 		mask = 0x7f;
1556 		break;
1557 	default:
1558 	case CS8:
1559 		lData = UART_LCR_WLEN8;
1560 		break;
1561 	}
1562 
1563 	/* Change the Parity bit */
1564 	if (cflag & PARENB) {
1565 		if (cflag & PARODD) {
1566 			lParity = UART_LCR_PARITY;
1567 			dev_dbg(&port->dev, "%s - parity = odd\n", __func__);
1568 		} else {
1569 			lParity = (UART_LCR_EPAR | UART_LCR_PARITY);
1570 			dev_dbg(&port->dev, "%s - parity = even\n", __func__);
1571 		}
1572 
1573 	} else {
1574 		dev_dbg(&port->dev, "%s - parity = none\n", __func__);
1575 	}
1576 
1577 	if (cflag & CMSPAR)
1578 		lParity = lParity | 0x20;
1579 
1580 	/* Change the Stop bit */
1581 	if (cflag & CSTOPB) {
1582 		lStop = UART_LCR_STOP;
1583 		dev_dbg(&port->dev, "%s - stop bits = 2\n", __func__);
1584 	} else {
1585 		lStop = 0x00;
1586 		dev_dbg(&port->dev, "%s - stop bits = 1\n", __func__);
1587 	}
1588 
1589 #define LCR_BITS_MASK		0x03	/* Mask for bits/char field */
1590 #define LCR_STOP_MASK		0x04	/* Mask for stop bits field */
1591 #define LCR_PAR_MASK		0x38	/* Mask for parity field */
1592 
1593 	/* Update the LCR with the correct value */
1594 	mos7720_port->shadowLCR &=
1595 		~(LCR_BITS_MASK | LCR_STOP_MASK | LCR_PAR_MASK);
1596 	mos7720_port->shadowLCR |= (lData | lParity | lStop);
1597 
1598 
1599 	/* Disable Interrupts */
1600 	write_mos_reg(serial, port_number, MOS7720_IER, 0x00);
1601 	write_mos_reg(serial, port_number, MOS7720_FCR, 0x00);
1602 	write_mos_reg(serial, port_number, MOS7720_FCR, 0xcf);
1603 
1604 	/* Send the updated LCR value to the mos7720 */
1605 	write_mos_reg(serial, port_number, MOS7720_LCR,
1606 		      mos7720_port->shadowLCR);
1607 	mos7720_port->shadowMCR = 0x0b;
1608 	write_mos_reg(serial, port_number, MOS7720_MCR,
1609 		      mos7720_port->shadowMCR);
1610 
1611 	/* set up the MCR register and send it to the mos7720 */
1612 	mos7720_port->shadowMCR = UART_MCR_OUT2;
1613 	if (cflag & CBAUD)
1614 		mos7720_port->shadowMCR |= (UART_MCR_DTR | UART_MCR_RTS);
1615 
1616 	if (cflag & CRTSCTS) {
1617 		mos7720_port->shadowMCR |= (UART_MCR_XONANY);
1618 		/* To set hardware flow control to the specified *
1619 		 * serial port, in SP1/2_CONTROL_REG             */
1620 		if (port_number)
1621 			write_mos_reg(serial, dummy, MOS7720_SP_CONTROL_REG,
1622 				      0x01);
1623 		else
1624 			write_mos_reg(serial, dummy, MOS7720_SP_CONTROL_REG,
1625 				      0x02);
1626 
1627 	} else
1628 		mos7720_port->shadowMCR &= ~(UART_MCR_XONANY);
1629 
1630 	write_mos_reg(serial, port_number, MOS7720_MCR,
1631 		      mos7720_port->shadowMCR);
1632 
1633 	/* Determine divisor based on baud rate */
1634 	baud = tty_get_baud_rate(tty);
1635 	if (!baud) {
1636 		/* pick a default, any default... */
1637 		dev_dbg(&port->dev, "Picked default baud...\n");
1638 		baud = 9600;
1639 	}
1640 
1641 	if (baud >= 230400) {
1642 		set_higher_rates(mos7720_port, baud);
1643 		/* Enable Interrupts */
1644 		write_mos_reg(serial, port_number, MOS7720_IER, 0x0c);
1645 		return;
1646 	}
1647 
1648 	dev_dbg(&port->dev, "%s - baud rate = %d\n", __func__, baud);
1649 	status = send_cmd_write_baud_rate(mos7720_port, baud);
1650 	/* FIXME: needs to write actual resulting baud back not just
1651 	   blindly do so */
1652 	if (cflag & CBAUD)
1653 		tty_encode_baud_rate(tty, baud, baud);
1654 	/* Enable Interrupts */
1655 	write_mos_reg(serial, port_number, MOS7720_IER, 0x0c);
1656 
1657 	if (port->read_urb->status != -EINPROGRESS) {
1658 		status = usb_submit_urb(port->read_urb, GFP_KERNEL);
1659 		if (status)
1660 			dev_dbg(&port->dev, "usb_submit_urb(read bulk) failed, status = %d\n", status);
1661 	}
1662 }
1663 
1664 /*
1665  * mos7720_set_termios
1666  *	this function is called by the tty driver when it wants to change the
1667  *	termios structure.
1668  */
1669 static void mos7720_set_termios(struct tty_struct *tty,
1670 		struct usb_serial_port *port, struct ktermios *old_termios)
1671 {
1672 	int status;
1673 	unsigned int cflag;
1674 	struct usb_serial *serial;
1675 	struct moschip_port *mos7720_port;
1676 
1677 	serial = port->serial;
1678 
1679 	mos7720_port = usb_get_serial_port_data(port);
1680 
1681 	if (mos7720_port == NULL)
1682 		return;
1683 
1684 	if (!mos7720_port->open) {
1685 		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
1686 		return;
1687 	}
1688 
1689 	dev_dbg(&port->dev, "setting termios - ASPIRE\n");
1690 
1691 	cflag = tty->termios.c_cflag;
1692 
1693 	dev_dbg(&port->dev, "%s - cflag %08x iflag %08x\n", __func__,
1694 		tty->termios.c_cflag, RELEVANT_IFLAG(tty->termios.c_iflag));
1695 
1696 	dev_dbg(&port->dev, "%s - old cflag %08x old iflag %08x\n", __func__,
1697 		old_termios->c_cflag, RELEVANT_IFLAG(old_termios->c_iflag));
1698 
1699 	/* change the port settings to the new ones specified */
1700 	change_port_settings(tty, mos7720_port, old_termios);
1701 
1702 	if (port->read_urb->status != -EINPROGRESS) {
1703 		status = usb_submit_urb(port->read_urb, GFP_KERNEL);
1704 		if (status)
1705 			dev_dbg(&port->dev, "usb_submit_urb(read bulk) failed, status = %d\n", status);
1706 	}
1707 }
1708 
1709 /*
1710  * get_lsr_info - get line status register info
1711  *
1712  * Purpose: Let user call ioctl() to get info when the UART physically
1713  * 	    is emptied.  On bus types like RS485, the transmitter must
1714  * 	    release the bus after transmitting. This must be done when
1715  * 	    the transmit shift register is empty, not be done when the
1716  * 	    transmit holding register is empty.  This functionality
1717  * 	    allows an RS485 driver to be written in user space.
1718  */
1719 static int get_lsr_info(struct tty_struct *tty,
1720 		struct moschip_port *mos7720_port, unsigned int __user *value)
1721 {
1722 	struct usb_serial_port *port = tty->driver_data;
1723 	unsigned int result = 0;
1724 	unsigned char data = 0;
1725 	int port_number = port->port_number;
1726 	int count;
1727 
1728 	count = mos7720_chars_in_buffer(tty);
1729 	if (count == 0) {
1730 		read_mos_reg(port->serial, port_number, MOS7720_LSR, &data);
1731 		if ((data & (UART_LSR_TEMT | UART_LSR_THRE))
1732 					== (UART_LSR_TEMT | UART_LSR_THRE)) {
1733 			dev_dbg(&port->dev, "%s -- Empty\n", __func__);
1734 			result = TIOCSER_TEMT;
1735 		}
1736 	}
1737 	if (copy_to_user(value, &result, sizeof(int)))
1738 		return -EFAULT;
1739 	return 0;
1740 }
1741 
1742 static int mos7720_tiocmget(struct tty_struct *tty)
1743 {
1744 	struct usb_serial_port *port = tty->driver_data;
1745 	struct moschip_port *mos7720_port = usb_get_serial_port_data(port);
1746 	unsigned int result = 0;
1747 	unsigned int mcr ;
1748 	unsigned int msr ;
1749 
1750 	mcr = mos7720_port->shadowMCR;
1751 	msr = mos7720_port->shadowMSR;
1752 
1753 	result = ((mcr & UART_MCR_DTR)  ? TIOCM_DTR : 0)   /* 0x002 */
1754 	  | ((mcr & UART_MCR_RTS)   ? TIOCM_RTS : 0)   /* 0x004 */
1755 	  | ((msr & UART_MSR_CTS)   ? TIOCM_CTS : 0)   /* 0x020 */
1756 	  | ((msr & UART_MSR_DCD)   ? TIOCM_CAR : 0)   /* 0x040 */
1757 	  | ((msr & UART_MSR_RI)    ? TIOCM_RI :  0)   /* 0x080 */
1758 	  | ((msr & UART_MSR_DSR)   ? TIOCM_DSR : 0);  /* 0x100 */
1759 
1760 	return result;
1761 }
1762 
1763 static int mos7720_tiocmset(struct tty_struct *tty,
1764 			    unsigned int set, unsigned int clear)
1765 {
1766 	struct usb_serial_port *port = tty->driver_data;
1767 	struct moschip_port *mos7720_port = usb_get_serial_port_data(port);
1768 	unsigned int mcr ;
1769 
1770 	mcr = mos7720_port->shadowMCR;
1771 
1772 	if (set & TIOCM_RTS)
1773 		mcr |= UART_MCR_RTS;
1774 	if (set & TIOCM_DTR)
1775 		mcr |= UART_MCR_DTR;
1776 	if (set & TIOCM_LOOP)
1777 		mcr |= UART_MCR_LOOP;
1778 
1779 	if (clear & TIOCM_RTS)
1780 		mcr &= ~UART_MCR_RTS;
1781 	if (clear & TIOCM_DTR)
1782 		mcr &= ~UART_MCR_DTR;
1783 	if (clear & TIOCM_LOOP)
1784 		mcr &= ~UART_MCR_LOOP;
1785 
1786 	mos7720_port->shadowMCR = mcr;
1787 	write_mos_reg(port->serial, port->port_number, MOS7720_MCR,
1788 		      mos7720_port->shadowMCR);
1789 
1790 	return 0;
1791 }
1792 
1793 static int set_modem_info(struct moschip_port *mos7720_port, unsigned int cmd,
1794 			  unsigned int __user *value)
1795 {
1796 	unsigned int mcr;
1797 	unsigned int arg;
1798 
1799 	struct usb_serial_port *port;
1800 
1801 	if (mos7720_port == NULL)
1802 		return -1;
1803 
1804 	port = (struct usb_serial_port *)mos7720_port->port;
1805 	mcr = mos7720_port->shadowMCR;
1806 
1807 	if (copy_from_user(&arg, value, sizeof(int)))
1808 		return -EFAULT;
1809 
1810 	switch (cmd) {
1811 	case TIOCMBIS:
1812 		if (arg & TIOCM_RTS)
1813 			mcr |= UART_MCR_RTS;
1814 		if (arg & TIOCM_DTR)
1815 			mcr |= UART_MCR_RTS;
1816 		if (arg & TIOCM_LOOP)
1817 			mcr |= UART_MCR_LOOP;
1818 		break;
1819 
1820 	case TIOCMBIC:
1821 		if (arg & TIOCM_RTS)
1822 			mcr &= ~UART_MCR_RTS;
1823 		if (arg & TIOCM_DTR)
1824 			mcr &= ~UART_MCR_RTS;
1825 		if (arg & TIOCM_LOOP)
1826 			mcr &= ~UART_MCR_LOOP;
1827 		break;
1828 
1829 	}
1830 
1831 	mos7720_port->shadowMCR = mcr;
1832 	write_mos_reg(port->serial, port->port_number, MOS7720_MCR,
1833 		      mos7720_port->shadowMCR);
1834 
1835 	return 0;
1836 }
1837 
1838 static int get_serial_info(struct moschip_port *mos7720_port,
1839 			   struct serial_struct __user *retinfo)
1840 {
1841 	struct serial_struct tmp;
1842 
1843 	memset(&tmp, 0, sizeof(tmp));
1844 
1845 	tmp.type		= PORT_16550A;
1846 	tmp.line		= mos7720_port->port->minor;
1847 	tmp.port		= mos7720_port->port->port_number;
1848 	tmp.irq			= 0;
1849 	tmp.flags		= ASYNC_SKIP_TEST | ASYNC_AUTO_IRQ;
1850 	tmp.xmit_fifo_size	= NUM_URBS * URB_TRANSFER_BUFFER_SIZE;
1851 	tmp.baud_base		= 9600;
1852 	tmp.close_delay		= 5*HZ;
1853 	tmp.closing_wait	= 30*HZ;
1854 
1855 	if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
1856 		return -EFAULT;
1857 	return 0;
1858 }
1859 
1860 static int mos7720_ioctl(struct tty_struct *tty,
1861 			 unsigned int cmd, unsigned long arg)
1862 {
1863 	struct usb_serial_port *port = tty->driver_data;
1864 	struct moschip_port *mos7720_port;
1865 
1866 	mos7720_port = usb_get_serial_port_data(port);
1867 	if (mos7720_port == NULL)
1868 		return -ENODEV;
1869 
1870 	switch (cmd) {
1871 	case TIOCSERGETLSR:
1872 		dev_dbg(&port->dev, "%s TIOCSERGETLSR\n", __func__);
1873 		return get_lsr_info(tty, mos7720_port,
1874 					(unsigned int __user *)arg);
1875 
1876 	/* FIXME: These should be using the mode methods */
1877 	case TIOCMBIS:
1878 	case TIOCMBIC:
1879 		dev_dbg(&port->dev, "%s TIOCMSET/TIOCMBIC/TIOCMSET\n", __func__);
1880 		return set_modem_info(mos7720_port, cmd,
1881 				      (unsigned int __user *)arg);
1882 
1883 	case TIOCGSERIAL:
1884 		dev_dbg(&port->dev, "%s TIOCGSERIAL\n", __func__);
1885 		return get_serial_info(mos7720_port,
1886 				       (struct serial_struct __user *)arg);
1887 	}
1888 
1889 	return -ENOIOCTLCMD;
1890 }
1891 
1892 static int mos7720_startup(struct usb_serial *serial)
1893 {
1894 	struct usb_device *dev;
1895 	char data;
1896 	u16 product;
1897 	int ret_val;
1898 
1899 	if (serial->num_bulk_in < 2 || serial->num_bulk_out < 2) {
1900 		dev_err(&serial->interface->dev, "missing bulk endpoints\n");
1901 		return -ENODEV;
1902 	}
1903 
1904 	product = le16_to_cpu(serial->dev->descriptor.idProduct);
1905 	dev = serial->dev;
1906 
1907 	/*
1908 	 * The 7715 uses the first bulk in/out endpoint pair for the parallel
1909 	 * port, and the second for the serial port.  Because the usbserial core
1910 	 * assumes both pairs are serial ports, we must engage in a bit of
1911 	 * subterfuge and swap the pointers for ports 0 and 1 in order to make
1912 	 * port 0 point to the serial port.  However, both moschip devices use a
1913 	 * single interrupt-in endpoint for both ports (as mentioned a little
1914 	 * further down), and this endpoint was assigned to port 0.  So after
1915 	 * the swap, we must copy the interrupt endpoint elements from port 1
1916 	 * (as newly assigned) to port 0, and null out port 1 pointers.
1917 	 */
1918 	if (product == MOSCHIP_DEVICE_ID_7715) {
1919 		struct usb_serial_port *tmp = serial->port[0];
1920 		serial->port[0] = serial->port[1];
1921 		serial->port[1] = tmp;
1922 		serial->port[0]->interrupt_in_urb = tmp->interrupt_in_urb;
1923 		serial->port[0]->interrupt_in_buffer = tmp->interrupt_in_buffer;
1924 		serial->port[0]->interrupt_in_endpointAddress =
1925 			tmp->interrupt_in_endpointAddress;
1926 		serial->port[1]->interrupt_in_urb = NULL;
1927 		serial->port[1]->interrupt_in_buffer = NULL;
1928 
1929 		if (serial->port[0]->interrupt_in_urb) {
1930 			struct urb *urb = serial->port[0]->interrupt_in_urb;
1931 
1932 			urb->complete = mos7715_interrupt_callback;
1933 		}
1934 	}
1935 
1936 	/* setting configuration feature to one */
1937 	usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
1938 			(__u8)0x03, 0x00, 0x01, 0x00, NULL, 0x00, 5000);
1939 
1940 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
1941 	if (product == MOSCHIP_DEVICE_ID_7715) {
1942 		ret_val = mos7715_parport_init(serial);
1943 		if (ret_val < 0)
1944 			return ret_val;
1945 	}
1946 #endif
1947 	/* start the interrupt urb */
1948 	ret_val = usb_submit_urb(serial->port[0]->interrupt_in_urb, GFP_KERNEL);
1949 	if (ret_val) {
1950 		dev_err(&dev->dev, "failed to submit interrupt urb: %d\n",
1951 			ret_val);
1952 	}
1953 
1954 	/* LSR For Port 1 */
1955 	read_mos_reg(serial, 0, MOS7720_LSR, &data);
1956 	dev_dbg(&dev->dev, "LSR:%x\n", data);
1957 
1958 	return 0;
1959 }
1960 
1961 static void mos7720_release(struct usb_serial *serial)
1962 {
1963 	usb_kill_urb(serial->port[0]->interrupt_in_urb);
1964 
1965 #ifdef CONFIG_USB_SERIAL_MOS7715_PARPORT
1966 	/* close the parallel port */
1967 
1968 	if (le16_to_cpu(serial->dev->descriptor.idProduct)
1969 	    == MOSCHIP_DEVICE_ID_7715) {
1970 		struct urbtracker *urbtrack;
1971 		unsigned long flags;
1972 		struct mos7715_parport *mos_parport =
1973 			usb_get_serial_data(serial);
1974 
1975 		/* prevent NULL ptr dereference in port callbacks */
1976 		spin_lock(&release_lock);
1977 		mos_parport->pp->private_data = NULL;
1978 		spin_unlock(&release_lock);
1979 
1980 		/* wait for synchronous usb calls to return */
1981 		if (mos_parport->msg_pending)
1982 			wait_for_completion_timeout(&mos_parport->syncmsg_compl,
1983 					    msecs_to_jiffies(MOS_WDR_TIMEOUT));
1984 
1985 		parport_remove_port(mos_parport->pp);
1986 		usb_set_serial_data(serial, NULL);
1987 		mos_parport->serial = NULL;
1988 
1989 		/* if tasklet currently scheduled, wait for it to complete */
1990 		tasklet_kill(&mos_parport->urb_tasklet);
1991 
1992 		/* unlink any urbs sent by the tasklet  */
1993 		spin_lock_irqsave(&mos_parport->listlock, flags);
1994 		list_for_each_entry(urbtrack,
1995 				    &mos_parport->active_urbs,
1996 				    urblist_entry)
1997 			usb_unlink_urb(urbtrack->urb);
1998 		spin_unlock_irqrestore(&mos_parport->listlock, flags);
1999 		parport_del_port(mos_parport->pp);
2000 
2001 		kref_put(&mos_parport->ref_count, destroy_mos_parport);
2002 	}
2003 #endif
2004 }
2005 
2006 static int mos7720_port_probe(struct usb_serial_port *port)
2007 {
2008 	struct moschip_port *mos7720_port;
2009 
2010 	mos7720_port = kzalloc(sizeof(*mos7720_port), GFP_KERNEL);
2011 	if (!mos7720_port)
2012 		return -ENOMEM;
2013 
2014 	mos7720_port->port = port;
2015 
2016 	usb_set_serial_port_data(port, mos7720_port);
2017 
2018 	return 0;
2019 }
2020 
2021 static int mos7720_port_remove(struct usb_serial_port *port)
2022 {
2023 	struct moschip_port *mos7720_port;
2024 
2025 	mos7720_port = usb_get_serial_port_data(port);
2026 	kfree(mos7720_port);
2027 
2028 	return 0;
2029 }
2030 
2031 static struct usb_serial_driver moschip7720_2port_driver = {
2032 	.driver = {
2033 		.owner =	THIS_MODULE,
2034 		.name =		"moschip7720",
2035 	},
2036 	.description		= "Moschip 2 port adapter",
2037 	.id_table		= id_table,
2038 	.calc_num_ports		= mos77xx_calc_num_ports,
2039 	.open			= mos7720_open,
2040 	.close			= mos7720_close,
2041 	.throttle		= mos7720_throttle,
2042 	.unthrottle		= mos7720_unthrottle,
2043 	.attach			= mos7720_startup,
2044 	.release		= mos7720_release,
2045 	.port_probe		= mos7720_port_probe,
2046 	.port_remove		= mos7720_port_remove,
2047 	.ioctl			= mos7720_ioctl,
2048 	.tiocmget		= mos7720_tiocmget,
2049 	.tiocmset		= mos7720_tiocmset,
2050 	.set_termios		= mos7720_set_termios,
2051 	.write			= mos7720_write,
2052 	.write_room		= mos7720_write_room,
2053 	.chars_in_buffer	= mos7720_chars_in_buffer,
2054 	.break_ctl		= mos7720_break,
2055 	.read_bulk_callback	= mos7720_bulk_in_callback,
2056 	.read_int_callback	= mos7720_interrupt_callback,
2057 };
2058 
2059 static struct usb_serial_driver * const serial_drivers[] = {
2060 	&moschip7720_2port_driver, NULL
2061 };
2062 
2063 module_usb_serial_driver(serial_drivers, id_table);
2064 
2065 MODULE_AUTHOR(DRIVER_AUTHOR);
2066 MODULE_DESCRIPTION(DRIVER_DESC);
2067 MODULE_LICENSE("GPL");
2068