1 /******************************************************************************
2  * usbtouchscreen.c
3  * Driver for USB Touchscreens, supporting those devices:
4  *  - eGalax Touchkit
5  *    includes eTurboTouch CT-410/510/700
6  *  - 3M/Microtouch  EX II series
7  *  - ITM
8  *  - PanJit TouchSet
9  *  - eTurboTouch
10  *  - Gunze AHL61
11  *  - DMC TSC-10/25
12  *  - IRTOUCHSYSTEMS/UNITOP
13  *
14  * Copyright (C) 2004-2006 by Daniel Ritz <daniel.ritz@gmx.ch>
15  * Copyright (C) by Todd E. Johnson (mtouchusb.c)
16  *
17  * This program is free software; you can redistribute it and/or
18  * modify it under the terms of the GNU General Public License as
19  * published by the Free Software Foundation; either version 2 of the
20  * License, or (at your option) any later version.
21  *
22  * This program is distributed in the hope that it will be useful, but
23  * WITHOUT ANY WARRANTY; without even the implied warranty of
24  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
25  * General Public License for more details.
26  *
27  * You should have received a copy of the GNU General Public License
28  * along with this program; if not, write to the Free Software
29  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
30  *
31  * Driver is based on touchkitusb.c
32  * - ITM parts are from itmtouch.c
33  * - 3M parts are from mtouchusb.c
34  * - PanJit parts are from an unmerged driver by Lanslott Gish
35  * - DMC TSC 10/25 are from Holger Schurig, with ideas from an unmerged
36  *   driver from Marius Vollmer
37  *
38  *****************************************************************************/
39 
40 //#define DEBUG
41 
42 #include <linux/kernel.h>
43 #include <linux/slab.h>
44 #include <linux/input.h>
45 #include <linux/module.h>
46 #include <linux/init.h>
47 #include <linux/usb.h>
48 #include <linux/usb/input.h>
49 
50 
51 #define DRIVER_VERSION		"v0.5"
52 #define DRIVER_AUTHOR		"Daniel Ritz <daniel.ritz@gmx.ch>"
53 #define DRIVER_DESC		"USB Touchscreen Driver"
54 
55 static int swap_xy;
56 module_param(swap_xy, bool, 0644);
57 MODULE_PARM_DESC(swap_xy, "If set X and Y axes are swapped.");
58 
59 /* device specifc data/functions */
60 struct usbtouch_usb;
61 struct usbtouch_device_info {
62 	int min_xc, max_xc;
63 	int min_yc, max_yc;
64 	int min_press, max_press;
65 	int rept_size;
66 	int flags;
67 
68 	void (*process_pkt) (struct usbtouch_usb *usbtouch, unsigned char *pkt, int len);
69 	int  (*get_pkt_len) (unsigned char *pkt, int len);
70 	int  (*read_data)   (struct usbtouch_usb *usbtouch, unsigned char *pkt);
71 	int  (*init)        (struct usbtouch_usb *usbtouch);
72 };
73 
74 #define USBTOUCH_FLG_BUFFER	0x01
75 
76 
77 /* a usbtouch device */
78 struct usbtouch_usb {
79 	unsigned char *data;
80 	dma_addr_t data_dma;
81 	unsigned char *buffer;
82 	int buf_len;
83 	struct urb *irq;
84 	struct usb_device *udev;
85 	struct input_dev *input;
86 	struct usbtouch_device_info *type;
87 	char name[128];
88 	char phys[64];
89 
90 	int x, y;
91 	int touch, press;
92 };
93 
94 
95 #if defined(CONFIG_TOUCHSCREEN_USB_EGALAX) || defined(CONFIG_TOUCHSCREEN_USB_ETURBO)
96 #define MULTI_PACKET
97 #endif
98 
99 #ifdef MULTI_PACKET
100 static void usbtouch_process_multi(struct usbtouch_usb *usbtouch,
101                                    unsigned char *pkt, int len);
102 #endif
103 
104 /* device types */
105 enum {
106 	DEVTPYE_DUMMY = -1,
107 	DEVTYPE_EGALAX,
108 	DEVTYPE_PANJIT,
109 	DEVTYPE_3M,
110 	DEVTYPE_ITM,
111 	DEVTYPE_ETURBO,
112 	DEVTYPE_GUNZE,
113 	DEVTYPE_DMC_TSC10,
114 	DEVTYPE_IRTOUCH,
115 };
116 
117 static struct usb_device_id usbtouch_devices[] = {
118 #ifdef CONFIG_TOUCHSCREEN_USB_EGALAX
119 	{USB_DEVICE(0x3823, 0x0001), .driver_info = DEVTYPE_EGALAX},
120 	{USB_DEVICE(0x3823, 0x0002), .driver_info = DEVTYPE_EGALAX},
121 	{USB_DEVICE(0x0123, 0x0001), .driver_info = DEVTYPE_EGALAX},
122 	{USB_DEVICE(0x0eef, 0x0001), .driver_info = DEVTYPE_EGALAX},
123 	{USB_DEVICE(0x0eef, 0x0002), .driver_info = DEVTYPE_EGALAX},
124 	{USB_DEVICE(0x1234, 0x0001), .driver_info = DEVTYPE_EGALAX},
125 	{USB_DEVICE(0x1234, 0x0002), .driver_info = DEVTYPE_EGALAX},
126 #endif
127 
128 #ifdef CONFIG_TOUCHSCREEN_USB_PANJIT
129 	{USB_DEVICE(0x134c, 0x0001), .driver_info = DEVTYPE_PANJIT},
130 	{USB_DEVICE(0x134c, 0x0002), .driver_info = DEVTYPE_PANJIT},
131 	{USB_DEVICE(0x134c, 0x0003), .driver_info = DEVTYPE_PANJIT},
132 	{USB_DEVICE(0x134c, 0x0004), .driver_info = DEVTYPE_PANJIT},
133 #endif
134 
135 #ifdef CONFIG_TOUCHSCREEN_USB_3M
136 	{USB_DEVICE(0x0596, 0x0001), .driver_info = DEVTYPE_3M},
137 #endif
138 
139 #ifdef CONFIG_TOUCHSCREEN_USB_ITM
140 	{USB_DEVICE(0x0403, 0xf9e9), .driver_info = DEVTYPE_ITM},
141 #endif
142 
143 #ifdef CONFIG_TOUCHSCREEN_USB_ETURBO
144 	{USB_DEVICE(0x1234, 0x5678), .driver_info = DEVTYPE_ETURBO},
145 #endif
146 
147 #ifdef CONFIG_TOUCHSCREEN_USB_GUNZE
148 	{USB_DEVICE(0x0637, 0x0001), .driver_info = DEVTYPE_GUNZE},
149 #endif
150 
151 #ifdef CONFIG_TOUCHSCREEN_USB_DMC_TSC10
152 	{USB_DEVICE(0x0afa, 0x03e8), .driver_info = DEVTYPE_DMC_TSC10},
153 #endif
154 
155 #ifdef CONFIG_TOUCHSCREEN_USB_IRTOUCH
156 	{USB_DEVICE(0x595a, 0x0001), .driver_info = DEVTYPE_IRTOUCH},
157 	{USB_DEVICE(0x6615, 0x0001), .driver_info = DEVTYPE_IRTOUCH},
158 #endif
159 
160 	{}
161 };
162 
163 
164 /*****************************************************************************
165  * eGalax part
166  */
167 
168 #ifdef CONFIG_TOUCHSCREEN_USB_EGALAX
169 
170 #define EGALAX_PKT_TYPE_MASK		0xFE
171 #define EGALAX_PKT_TYPE_REPT		0x80
172 #define EGALAX_PKT_TYPE_DIAG		0x0A
173 
174 static int egalax_read_data(struct usbtouch_usb *dev, unsigned char *pkt)
175 {
176 	if ((pkt[0] & EGALAX_PKT_TYPE_MASK) != EGALAX_PKT_TYPE_REPT)
177 		return 0;
178 
179 	dev->x = ((pkt[3] & 0x0F) << 7) | (pkt[4] & 0x7F);
180 	dev->y = ((pkt[1] & 0x0F) << 7) | (pkt[2] & 0x7F);
181 	dev->touch = pkt[0] & 0x01;
182 
183 	return 1;
184 }
185 
186 static int egalax_get_pkt_len(unsigned char *buf, int len)
187 {
188 	switch (buf[0] & EGALAX_PKT_TYPE_MASK) {
189 	case EGALAX_PKT_TYPE_REPT:
190 		return 5;
191 
192 	case EGALAX_PKT_TYPE_DIAG:
193 		if (len < 2)
194 			return -1;
195 
196 		return buf[1] + 2;
197 	}
198 
199 	return 0;
200 }
201 #endif
202 
203 
204 /*****************************************************************************
205  * PanJit Part
206  */
207 #ifdef CONFIG_TOUCHSCREEN_USB_PANJIT
208 static int panjit_read_data(struct usbtouch_usb *dev, unsigned char *pkt)
209 {
210 	dev->x = ((pkt[2] & 0x0F) << 8) | pkt[1];
211 	dev->y = ((pkt[4] & 0x0F) << 8) | pkt[3];
212 	dev->touch = pkt[0] & 0x01;
213 
214 	return 1;
215 }
216 #endif
217 
218 
219 /*****************************************************************************
220  * 3M/Microtouch Part
221  */
222 #ifdef CONFIG_TOUCHSCREEN_USB_3M
223 
224 #define MTOUCHUSB_ASYNC_REPORT          1
225 #define MTOUCHUSB_RESET                 7
226 #define MTOUCHUSB_REQ_CTRLLR_ID         10
227 
228 static int mtouch_read_data(struct usbtouch_usb *dev, unsigned char *pkt)
229 {
230 	dev->x = (pkt[8] << 8) | pkt[7];
231 	dev->y = (pkt[10] << 8) | pkt[9];
232 	dev->touch = (pkt[2] & 0x40) ? 1 : 0;
233 
234 	return 1;
235 }
236 
237 static int mtouch_init(struct usbtouch_usb *usbtouch)
238 {
239 	int ret, i;
240 
241 	ret = usb_control_msg(usbtouch->udev, usb_rcvctrlpipe(usbtouch->udev, 0),
242 	                      MTOUCHUSB_RESET,
243 	                      USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
244 	                      1, 0, NULL, 0, USB_CTRL_SET_TIMEOUT);
245 	dbg("%s - usb_control_msg - MTOUCHUSB_RESET - bytes|err: %d",
246 	    __FUNCTION__, ret);
247 	if (ret < 0)
248 		return ret;
249 	msleep(150);
250 
251 	for (i = 0; i < 3; i++) {
252 		ret = usb_control_msg(usbtouch->udev, usb_rcvctrlpipe(usbtouch->udev, 0),
253 				      MTOUCHUSB_ASYNC_REPORT,
254 				      USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
255 				      1, 1, NULL, 0, USB_CTRL_SET_TIMEOUT);
256 		dbg("%s - usb_control_msg - MTOUCHUSB_ASYNC_REPORT - bytes|err: %d",
257 		    __FUNCTION__, ret);
258 		if (ret >= 0)
259 			break;
260 		if (ret != -EPIPE)
261 			return ret;
262 	}
263 
264 	return 0;
265 }
266 #endif
267 
268 
269 /*****************************************************************************
270  * ITM Part
271  */
272 #ifdef CONFIG_TOUCHSCREEN_USB_ITM
273 static int itm_read_data(struct usbtouch_usb *dev, unsigned char *pkt)
274 {
275 	int touch;
276 	/*
277 	 * ITM devices report invalid x/y data if not touched.
278 	 * if the screen was touched before but is not touched any more
279 	 * report touch as 0 with the last valid x/y data once. then stop
280 	 * reporting data until touched again.
281 	 */
282 	dev->press = ((pkt[2] & 0x01) << 7) | (pkt[5] & 0x7F);
283 
284 	touch = ~pkt[7] & 0x20;
285 	if (!touch) {
286 		if (dev->touch) {
287 			dev->touch = 0;
288 			return 1;
289 		}
290 
291 		return 0;
292 	}
293 
294 	dev->x = ((pkt[0] & 0x1F) << 7) | (pkt[3] & 0x7F);
295 	dev->y = ((pkt[1] & 0x1F) << 7) | (pkt[4] & 0x7F);
296 	dev->touch = touch;
297 
298 	return 1;
299 }
300 #endif
301 
302 
303 /*****************************************************************************
304  * eTurboTouch part
305  */
306 #ifdef CONFIG_TOUCHSCREEN_USB_ETURBO
307 static int eturbo_read_data(struct usbtouch_usb *dev, unsigned char *pkt)
308 {
309 	unsigned int shift;
310 
311 	/* packets should start with sync */
312 	if (!(pkt[0] & 0x80))
313 		return 0;
314 
315 	shift = (6 - (pkt[0] & 0x03));
316 	dev->x = ((pkt[3] << 7) | pkt[4]) >> shift;
317 	dev->y = ((pkt[1] << 7) | pkt[2]) >> shift;
318 	dev->touch = (pkt[0] & 0x10) ? 1 : 0;
319 
320 	return 1;
321 }
322 
323 static int eturbo_get_pkt_len(unsigned char *buf, int len)
324 {
325 	if (buf[0] & 0x80)
326 		return 5;
327 	if (buf[0] == 0x01)
328 		return 3;
329 	return 0;
330 }
331 #endif
332 
333 
334 /*****************************************************************************
335  * Gunze part
336  */
337 #ifdef CONFIG_TOUCHSCREEN_USB_GUNZE
338 static int gunze_read_data(struct usbtouch_usb *dev, unsigned char *pkt)
339 {
340 	if (!(pkt[0] & 0x80) || ((pkt[1] | pkt[2] | pkt[3]) & 0x80))
341 		return 0;
342 
343 	dev->x = ((pkt[0] & 0x1F) << 7) | (pkt[2] & 0x7F);
344 	dev->y = ((pkt[1] & 0x1F) << 7) | (pkt[3] & 0x7F);
345 	dev->touch = pkt[0] & 0x20;
346 
347 	return 1;
348 }
349 #endif
350 
351 /*****************************************************************************
352  * DMC TSC-10/25 Part
353  *
354  * Documentation about the controller and it's protocol can be found at
355  *   http://www.dmccoltd.com/files/controler/tsc10usb_pi_e.pdf
356  *   http://www.dmccoltd.com/files/controler/tsc25_usb_e.pdf
357  */
358 #ifdef CONFIG_TOUCHSCREEN_USB_DMC_TSC10
359 
360 /* supported data rates. currently using 130 */
361 #define TSC10_RATE_POINT	0x50
362 #define TSC10_RATE_30		0x40
363 #define TSC10_RATE_50		0x41
364 #define TSC10_RATE_80		0x42
365 #define TSC10_RATE_100		0x43
366 #define TSC10_RATE_130		0x44
367 #define TSC10_RATE_150		0x45
368 
369 /* commands */
370 #define TSC10_CMD_RESET		0x55
371 #define TSC10_CMD_RATE		0x05
372 #define TSC10_CMD_DATA1		0x01
373 
374 static int dmc_tsc10_init(struct usbtouch_usb *usbtouch)
375 {
376 	struct usb_device *dev = usbtouch->udev;
377 	int ret;
378 	unsigned char buf[2];
379 
380 	/* reset */
381 	buf[0] = buf[1] = 0xFF;
382 	ret = usb_control_msg(dev, usb_rcvctrlpipe (dev, 0),
383 	                      TSC10_CMD_RESET,
384 	                      USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
385 	                      0, 0, buf, 2, USB_CTRL_SET_TIMEOUT);
386 	if (ret < 0)
387 		return ret;
388 	if (buf[0] != 0x06 || buf[1] != 0x00)
389 		return -ENODEV;
390 
391 	/* set coordinate output rate */
392 	buf[0] = buf[1] = 0xFF;
393 	ret = usb_control_msg(dev, usb_rcvctrlpipe (dev, 0),
394 	                      TSC10_CMD_RATE,
395 	                      USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
396 	                      TSC10_RATE_150, 0, buf, 2, USB_CTRL_SET_TIMEOUT);
397 	if (ret < 0)
398 		return ret;
399 	if (buf[0] != 0x06 || buf[1] != 0x00)
400 		return -ENODEV;
401 
402 	/* start sending data */
403 	ret = usb_control_msg(dev, usb_rcvctrlpipe (dev, 0),
404 	                      TSC10_CMD_DATA1,
405 	                      USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
406 	                      0, 0, NULL, 0, USB_CTRL_SET_TIMEOUT);
407 	if (ret < 0)
408 		return ret;
409 
410 	return 0;
411 }
412 
413 
414 static int dmc_tsc10_read_data(struct usbtouch_usb *dev, unsigned char *pkt)
415 {
416 	dev->x = ((pkt[2] & 0x03) << 8) | pkt[1];
417 	dev->y = ((pkt[4] & 0x03) << 8) | pkt[3];
418 	dev->touch = pkt[0] & 0x01;
419 
420 	return 1;
421 }
422 #endif
423 
424 
425 /*****************************************************************************
426  * IRTOUCH Part
427  */
428 #ifdef CONFIG_TOUCHSCREEN_USB_IRTOUCH
429 static int irtouch_read_data(struct usbtouch_usb *dev, unsigned char *pkt)
430 {
431 	dev->x = (pkt[3] << 8) | pkt[2];
432 	dev->y = (pkt[5] << 8) | pkt[4];
433 	dev->touch = (pkt[1] & 0x03) ? 1 : 0;
434 
435 	return 1;
436 }
437 #endif
438 
439 
440 /*****************************************************************************
441  * the different device descriptors
442  */
443 static struct usbtouch_device_info usbtouch_dev_info[] = {
444 #ifdef CONFIG_TOUCHSCREEN_USB_EGALAX
445 	[DEVTYPE_EGALAX] = {
446 		.min_xc		= 0x0,
447 		.max_xc		= 0x07ff,
448 		.min_yc		= 0x0,
449 		.max_yc		= 0x07ff,
450 		.rept_size	= 16,
451 		.flags		= USBTOUCH_FLG_BUFFER,
452 		.process_pkt	= usbtouch_process_multi,
453 		.get_pkt_len	= egalax_get_pkt_len,
454 		.read_data	= egalax_read_data,
455 	},
456 #endif
457 
458 #ifdef CONFIG_TOUCHSCREEN_USB_PANJIT
459 	[DEVTYPE_PANJIT] = {
460 		.min_xc		= 0x0,
461 		.max_xc		= 0x0fff,
462 		.min_yc		= 0x0,
463 		.max_yc		= 0x0fff,
464 		.rept_size	= 8,
465 		.read_data	= panjit_read_data,
466 	},
467 #endif
468 
469 #ifdef CONFIG_TOUCHSCREEN_USB_3M
470 	[DEVTYPE_3M] = {
471 		.min_xc		= 0x0,
472 		.max_xc		= 0x4000,
473 		.min_yc		= 0x0,
474 		.max_yc		= 0x4000,
475 		.rept_size	= 11,
476 		.read_data	= mtouch_read_data,
477 		.init		= mtouch_init,
478 	},
479 #endif
480 
481 #ifdef CONFIG_TOUCHSCREEN_USB_ITM
482 	[DEVTYPE_ITM] = {
483 		.min_xc		= 0x0,
484 		.max_xc		= 0x0fff,
485 		.min_yc		= 0x0,
486 		.max_yc		= 0x0fff,
487 		.max_press	= 0xff,
488 		.rept_size	= 8,
489 		.read_data	= itm_read_data,
490 	},
491 #endif
492 
493 #ifdef CONFIG_TOUCHSCREEN_USB_ETURBO
494 	[DEVTYPE_ETURBO] = {
495 		.min_xc		= 0x0,
496 		.max_xc		= 0x07ff,
497 		.min_yc		= 0x0,
498 		.max_yc		= 0x07ff,
499 		.rept_size	= 8,
500 		.flags		= USBTOUCH_FLG_BUFFER,
501 		.process_pkt	= usbtouch_process_multi,
502 		.get_pkt_len	= eturbo_get_pkt_len,
503 		.read_data	= eturbo_read_data,
504 	},
505 #endif
506 
507 #ifdef CONFIG_TOUCHSCREEN_USB_GUNZE
508 	[DEVTYPE_GUNZE] = {
509 		.min_xc		= 0x0,
510 		.max_xc		= 0x0fff,
511 		.min_yc		= 0x0,
512 		.max_yc		= 0x0fff,
513 		.rept_size	= 4,
514 		.read_data	= gunze_read_data,
515 	},
516 #endif
517 
518 #ifdef CONFIG_TOUCHSCREEN_USB_DMC_TSC10
519 	[DEVTYPE_DMC_TSC10] = {
520 		.min_xc		= 0x0,
521 		.max_xc		= 0x03ff,
522 		.min_yc		= 0x0,
523 		.max_yc		= 0x03ff,
524 		.rept_size	= 5,
525 		.init		= dmc_tsc10_init,
526 		.read_data	= dmc_tsc10_read_data,
527 	},
528 #endif
529 
530 #ifdef CONFIG_TOUCHSCREEN_USB_IRTOUCH
531 	[DEVTYPE_IRTOUCH] = {
532 		.min_xc		= 0x0,
533 		.max_xc		= 0x0fff,
534 		.min_yc		= 0x0,
535 		.max_yc		= 0x0fff,
536 		.rept_size	= 8,
537 		.read_data	= irtouch_read_data,
538 	},
539 #endif
540 };
541 
542 
543 /*****************************************************************************
544  * Generic Part
545  */
546 static void usbtouch_process_pkt(struct usbtouch_usb *usbtouch,
547                                  unsigned char *pkt, int len)
548 {
549 	struct usbtouch_device_info *type = usbtouch->type;
550 
551 	if (!type->read_data(usbtouch, pkt))
552 			return;
553 
554 	input_report_key(usbtouch->input, BTN_TOUCH, usbtouch->touch);
555 
556 	if (swap_xy) {
557 		input_report_abs(usbtouch->input, ABS_X, usbtouch->y);
558 		input_report_abs(usbtouch->input, ABS_Y, usbtouch->x);
559 	} else {
560 		input_report_abs(usbtouch->input, ABS_X, usbtouch->x);
561 		input_report_abs(usbtouch->input, ABS_Y, usbtouch->y);
562 	}
563 	if (type->max_press)
564 		input_report_abs(usbtouch->input, ABS_PRESSURE, usbtouch->press);
565 	input_sync(usbtouch->input);
566 }
567 
568 
569 #ifdef MULTI_PACKET
570 static void usbtouch_process_multi(struct usbtouch_usb *usbtouch,
571                                    unsigned char *pkt, int len)
572 {
573 	unsigned char *buffer;
574 	int pkt_len, pos, buf_len, tmp;
575 
576 	/* process buffer */
577 	if (unlikely(usbtouch->buf_len)) {
578 		/* try to get size */
579 		pkt_len = usbtouch->type->get_pkt_len(
580 				usbtouch->buffer, usbtouch->buf_len);
581 
582 		/* drop? */
583 		if (unlikely(!pkt_len))
584 			goto out_flush_buf;
585 
586 		/* need to append -pkt_len bytes before able to get size */
587 		if (unlikely(pkt_len < 0)) {
588 			int append = -pkt_len;
589 			if (unlikely(append > len))
590 			       append = len;
591 			if (usbtouch->buf_len + append >= usbtouch->type->rept_size)
592 				goto out_flush_buf;
593 			memcpy(usbtouch->buffer + usbtouch->buf_len, pkt, append);
594 			usbtouch->buf_len += append;
595 
596 			pkt_len = usbtouch->type->get_pkt_len(
597 					usbtouch->buffer, usbtouch->buf_len);
598 			if (pkt_len < 0)
599 				return;
600 		}
601 
602 		/* append */
603 		tmp = pkt_len - usbtouch->buf_len;
604 		if (usbtouch->buf_len + tmp >= usbtouch->type->rept_size)
605 			goto out_flush_buf;
606 		memcpy(usbtouch->buffer + usbtouch->buf_len, pkt, tmp);
607 		usbtouch_process_pkt(usbtouch, usbtouch->buffer, pkt_len);
608 
609 		buffer = pkt + tmp;
610 		buf_len = len - tmp;
611 	} else {
612 		buffer = pkt;
613 		buf_len = len;
614 	}
615 
616 	/* loop over the received packet, process */
617 	pos = 0;
618 	while (pos < buf_len) {
619 		/* get packet len */
620 		pkt_len = usbtouch->type->get_pkt_len(buffer + pos, len);
621 
622 		/* unknown packet: drop everything */
623 		if (unlikely(!pkt_len))
624 			goto out_flush_buf;
625 
626 		/* full packet: process */
627 		if (likely((pkt_len > 0) && (pkt_len <= buf_len - pos))) {
628 			usbtouch_process_pkt(usbtouch, buffer + pos, pkt_len);
629 		} else {
630 			/* incomplete packet: save in buffer */
631 			memcpy(usbtouch->buffer, buffer + pos, buf_len - pos);
632 			usbtouch->buf_len = buf_len - pos;
633 			return;
634 		}
635 		pos += pkt_len;
636 	}
637 
638 out_flush_buf:
639 	usbtouch->buf_len = 0;
640 	return;
641 }
642 #endif
643 
644 
645 static void usbtouch_irq(struct urb *urb)
646 {
647 	struct usbtouch_usb *usbtouch = urb->context;
648 	int retval;
649 
650 	switch (urb->status) {
651 	case 0:
652 		/* success */
653 		break;
654 	case -ETIME:
655 		/* this urb is timing out */
656 		dbg("%s - urb timed out - was the device unplugged?",
657 		    __FUNCTION__);
658 		return;
659 	case -ECONNRESET:
660 	case -ENOENT:
661 	case -ESHUTDOWN:
662 		/* this urb is terminated, clean up */
663 		dbg("%s - urb shutting down with status: %d",
664 		    __FUNCTION__, urb->status);
665 		return;
666 	default:
667 		dbg("%s - nonzero urb status received: %d",
668 		    __FUNCTION__, urb->status);
669 		goto exit;
670 	}
671 
672 	usbtouch->type->process_pkt(usbtouch, usbtouch->data, urb->actual_length);
673 
674 exit:
675 	retval = usb_submit_urb(urb, GFP_ATOMIC);
676 	if (retval)
677 		err("%s - usb_submit_urb failed with result: %d",
678 		    __FUNCTION__, retval);
679 }
680 
681 static int usbtouch_open(struct input_dev *input)
682 {
683 	struct usbtouch_usb *usbtouch = input_get_drvdata(input);
684 
685 	usbtouch->irq->dev = usbtouch->udev;
686 
687 	if (usb_submit_urb(usbtouch->irq, GFP_KERNEL))
688 		return -EIO;
689 
690 	return 0;
691 }
692 
693 static void usbtouch_close(struct input_dev *input)
694 {
695 	struct usbtouch_usb *usbtouch = input_get_drvdata(input);
696 
697 	usb_kill_urb(usbtouch->irq);
698 }
699 
700 
701 static void usbtouch_free_buffers(struct usb_device *udev,
702 				  struct usbtouch_usb *usbtouch)
703 {
704 	usb_buffer_free(udev, usbtouch->type->rept_size,
705 	                usbtouch->data, usbtouch->data_dma);
706 	kfree(usbtouch->buffer);
707 }
708 
709 
710 static int usbtouch_probe(struct usb_interface *intf,
711 			  const struct usb_device_id *id)
712 {
713 	struct usbtouch_usb *usbtouch;
714 	struct input_dev *input_dev;
715 	struct usb_host_interface *interface;
716 	struct usb_endpoint_descriptor *endpoint;
717 	struct usb_device *udev = interface_to_usbdev(intf);
718 	struct usbtouch_device_info *type;
719 	int err = -ENOMEM;
720 
721 	interface = intf->cur_altsetting;
722 	endpoint = &interface->endpoint[0].desc;
723 
724 	usbtouch = kzalloc(sizeof(struct usbtouch_usb), GFP_KERNEL);
725 	input_dev = input_allocate_device();
726 	if (!usbtouch || !input_dev)
727 		goto out_free;
728 
729 	type = &usbtouch_dev_info[id->driver_info];
730 	usbtouch->type = type;
731 	if (!type->process_pkt)
732 		type->process_pkt = usbtouch_process_pkt;
733 
734 	usbtouch->data = usb_buffer_alloc(udev, type->rept_size,
735 	                                  GFP_KERNEL, &usbtouch->data_dma);
736 	if (!usbtouch->data)
737 		goto out_free;
738 
739 	if (type->flags & USBTOUCH_FLG_BUFFER) {
740 		usbtouch->buffer = kmalloc(type->rept_size, GFP_KERNEL);
741 		if (!usbtouch->buffer)
742 			goto out_free_buffers;
743 	}
744 
745 	usbtouch->irq = usb_alloc_urb(0, GFP_KERNEL);
746 	if (!usbtouch->irq) {
747 		dbg("%s - usb_alloc_urb failed: usbtouch->irq", __FUNCTION__);
748 		goto out_free_buffers;
749 	}
750 
751 	usbtouch->udev = udev;
752 	usbtouch->input = input_dev;
753 
754 	if (udev->manufacturer)
755 		strlcpy(usbtouch->name, udev->manufacturer, sizeof(usbtouch->name));
756 
757 	if (udev->product) {
758 		if (udev->manufacturer)
759 			strlcat(usbtouch->name, " ", sizeof(usbtouch->name));
760 		strlcat(usbtouch->name, udev->product, sizeof(usbtouch->name));
761 	}
762 
763 	if (!strlen(usbtouch->name))
764 		snprintf(usbtouch->name, sizeof(usbtouch->name),
765 			"USB Touchscreen %04x:%04x",
766 			 le16_to_cpu(udev->descriptor.idVendor),
767 			 le16_to_cpu(udev->descriptor.idProduct));
768 
769 	usb_make_path(udev, usbtouch->phys, sizeof(usbtouch->phys));
770 	strlcpy(usbtouch->phys, "/input0", sizeof(usbtouch->phys));
771 
772 	input_dev->name = usbtouch->name;
773 	input_dev->phys = usbtouch->phys;
774 	usb_to_input_id(udev, &input_dev->id);
775 	input_dev->dev.parent = &intf->dev;
776 
777 	input_set_drvdata(input_dev, usbtouch);
778 
779 	input_dev->open = usbtouch_open;
780 	input_dev->close = usbtouch_close;
781 
782 	input_dev->evbit[0] = BIT(EV_KEY) | BIT(EV_ABS);
783 	input_dev->keybit[LONG(BTN_TOUCH)] = BIT(BTN_TOUCH);
784 	input_set_abs_params(input_dev, ABS_X, type->min_xc, type->max_xc, 0, 0);
785 	input_set_abs_params(input_dev, ABS_Y, type->min_yc, type->max_yc, 0, 0);
786 	if (type->max_press)
787 		input_set_abs_params(input_dev, ABS_PRESSURE, type->min_press,
788 		                     type->max_press, 0, 0);
789 
790 	usb_fill_int_urb(usbtouch->irq, usbtouch->udev,
791 			 usb_rcvintpipe(usbtouch->udev, endpoint->bEndpointAddress),
792 			 usbtouch->data, type->rept_size,
793 			 usbtouch_irq, usbtouch, endpoint->bInterval);
794 
795 	usbtouch->irq->dev = usbtouch->udev;
796 	usbtouch->irq->transfer_dma = usbtouch->data_dma;
797 	usbtouch->irq->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
798 
799 	/* device specific init */
800 	if (type->init) {
801 		err = type->init(usbtouch);
802 		if (err) {
803 			dbg("%s - type->init() failed, err: %d", __FUNCTION__, err);
804 			goto out_free_buffers;
805 		}
806 	}
807 
808 	err = input_register_device(usbtouch->input);
809 	if (err) {
810 		dbg("%s - input_register_device failed, err: %d", __FUNCTION__, err);
811 		goto out_free_buffers;
812 	}
813 
814 	usb_set_intfdata(intf, usbtouch);
815 
816 	return 0;
817 
818 out_free_buffers:
819 	usbtouch_free_buffers(udev, usbtouch);
820 out_free:
821 	input_free_device(input_dev);
822 	kfree(usbtouch);
823 	return err;
824 }
825 
826 static void usbtouch_disconnect(struct usb_interface *intf)
827 {
828 	struct usbtouch_usb *usbtouch = usb_get_intfdata(intf);
829 
830 	dbg("%s - called", __FUNCTION__);
831 
832 	if (!usbtouch)
833 		return;
834 
835 	dbg("%s - usbtouch is initialized, cleaning up", __FUNCTION__);
836 	usb_set_intfdata(intf, NULL);
837 	usb_kill_urb(usbtouch->irq);
838 	input_unregister_device(usbtouch->input);
839 	usb_free_urb(usbtouch->irq);
840 	usbtouch_free_buffers(interface_to_usbdev(intf), usbtouch);
841 	kfree(usbtouch);
842 }
843 
844 MODULE_DEVICE_TABLE(usb, usbtouch_devices);
845 
846 static struct usb_driver usbtouch_driver = {
847 	.name		= "usbtouchscreen",
848 	.probe		= usbtouch_probe,
849 	.disconnect	= usbtouch_disconnect,
850 	.id_table	= usbtouch_devices,
851 };
852 
853 static int __init usbtouch_init(void)
854 {
855 	return usb_register(&usbtouch_driver);
856 }
857 
858 static void __exit usbtouch_cleanup(void)
859 {
860 	usb_deregister(&usbtouch_driver);
861 }
862 
863 module_init(usbtouch_init);
864 module_exit(usbtouch_cleanup);
865 
866 MODULE_AUTHOR(DRIVER_AUTHOR);
867 MODULE_DESCRIPTION(DRIVER_DESC);
868 MODULE_LICENSE("GPL");
869 
870 MODULE_ALIAS("touchkitusb");
871 MODULE_ALIAS("itmtouch");
872 MODULE_ALIAS("mtouchusb");
873