1/*
2 * Wacom W8001 penabled serial touchscreen driver
3 *
4 * Copyright (c) 2008 Jaya Kumar
5 * Copyright (c) 2010 Red Hat, Inc.
6 * Copyright (c) 2010 - 2011 Ping Cheng, Wacom. <pingc@wacom.com>
7 *
8 * This file is subject to the terms and conditions of the GNU General Public
9 * License. See the file COPYING in the main directory of this archive for
10 * more details.
11 *
12 * Layout based on Elo serial touchscreen driver by Vojtech Pavlik
13 */
14
15#include <linux/errno.h>
16#include <linux/kernel.h>
17#include <linux/module.h>
18#include <linux/slab.h>
19#include <linux/input/mt.h>
20#include <linux/serio.h>
21#include <linux/ctype.h>
22#include <linux/delay.h>
23
24#define DRIVER_DESC "Wacom W8001 serial touchscreen driver"
25
26MODULE_AUTHOR("Jaya Kumar <jayakumar.lkml@gmail.com>");
27MODULE_DESCRIPTION(DRIVER_DESC);
28MODULE_LICENSE("GPL");
29
30#define W8001_MAX_PHYS 42
31
32#define W8001_MAX_LENGTH 13
33#define W8001_LEAD_MASK 0x80
34#define W8001_LEAD_BYTE 0x80
35#define W8001_TAB_MASK 0x40
36#define W8001_TAB_BYTE 0x40
37/* set in first byte of touch data packets */
38#define W8001_TOUCH_MASK (0x10 | W8001_LEAD_MASK)
39#define W8001_TOUCH_BYTE (0x10 | W8001_LEAD_BYTE)
40
41#define W8001_QUERY_PACKET 0x20
42
43#define W8001_CMD_STOP '0'
44#define W8001_CMD_START '1'
45#define W8001_CMD_QUERY '*'
46#define W8001_CMD_TOUCHQUERY '%'
47
48/* length of data packets in bytes, depends on device. */
49#define W8001_PKTLEN_TOUCH93 5
50#define W8001_PKTLEN_TOUCH9A 7
51#define W8001_PKTLEN_TPCPEN 9
52#define W8001_PKTLEN_TPCCTL 11 /* control packet */
53#define W8001_PKTLEN_TOUCH2FG 13
54
55/* resolution in points/mm */
56#define W8001_PEN_RESOLUTION 100
57#define W8001_TOUCH_RESOLUTION 10
58
59struct w8001_coord {
60 u8 rdy;
61 u8 tsw;
62 u8 f1;
63 u8 f2;
64 u16 x;
65 u16 y;
66 u16 pen_pressure;
67 u8 tilt_x;
68 u8 tilt_y;
69};
70
71/* touch query reply packet */
72struct w8001_touch_query {
73 u16 x;
74 u16 y;
75 u8 panel_res;
76 u8 capacity_res;
77 u8 sensor_id;
78};
79
80/*
81 * Per-touchscreen data.
82 */
83
84struct w8001 {
85 struct input_dev *pen_dev;
86 struct input_dev *touch_dev;
87 struct serio *serio;
88 struct completion cmd_done;
89 int id;
90 int idx;
91 unsigned char response_type;
92 unsigned char response[W8001_MAX_LENGTH];
93 unsigned char data[W8001_MAX_LENGTH];
94 char phys[W8001_MAX_PHYS];
95 int type;
96 unsigned int pktlen;
97 u16 max_touch_x;
98 u16 max_touch_y;
99 u16 max_pen_x;
100 u16 max_pen_y;
101 char pen_name[64];
102 char touch_name[64];
103 int open_count;
104 struct mutex mutex;
105};
106
107static void parse_pen_data(u8 *data, struct w8001_coord *coord)
108{
109 memset(coord, 0, sizeof(*coord));
110
111 coord->rdy = data[0] & 0x20;
112 coord->tsw = data[0] & 0x01;
113 coord->f1 = data[0] & 0x02;
114 coord->f2 = data[0] & 0x04;
115
116 coord->x = (data[1] & 0x7F) << 9;
117 coord->x |= (data[2] & 0x7F) << 2;
118 coord->x |= (data[6] & 0x60) >> 5;
119
120 coord->y = (data[3] & 0x7F) << 9;
121 coord->y |= (data[4] & 0x7F) << 2;
122 coord->y |= (data[6] & 0x18) >> 3;
123
124 coord->pen_pressure = data[5] & 0x7F;
125 coord->pen_pressure |= (data[6] & 0x07) << 7 ;
126
127 coord->tilt_x = data[7] & 0x7F;
128 coord->tilt_y = data[8] & 0x7F;
129}
130
131static void parse_single_touch(u8 *data, struct w8001_coord *coord)
132{
133 coord->x = (data[1] << 7) | data[2];
134 coord->y = (data[3] << 7) | data[4];
135 coord->tsw = data[0] & 0x01;
136}
137
138static void scale_touch_coordinates(struct w8001 *w8001,
139 unsigned int *x, unsigned int *y)
140{
141 if (w8001->max_pen_x && w8001->max_touch_x)
142 *x = *x * w8001->max_pen_x / w8001->max_touch_x;
143
144 if (w8001->max_pen_y && w8001->max_touch_y)
145 *y = *y * w8001->max_pen_y / w8001->max_touch_y;
146}
147
148static void parse_multi_touch(struct w8001 *w8001)
149{
150 struct input_dev *dev = w8001->touch_dev;
151 unsigned char *data = w8001->data;
152 unsigned int x, y;
153 int i;
154 int count = 0;
155
156 for (i = 0; i < 2; i++) {
157 bool touch = data[0] & (1 << i);
158
159 input_mt_slot(dev, slot: i);
160 input_mt_report_slot_state(dev, MT_TOOL_FINGER, active: touch);
161 if (touch) {
162 x = (data[6 * i + 1] << 7) | data[6 * i + 2];
163 y = (data[6 * i + 3] << 7) | data[6 * i + 4];
164 /* data[5,6] and [11,12] is finger capacity */
165
166 /* scale to pen maximum */
167 scale_touch_coordinates(w8001, x: &x, y: &y);
168
169 input_report_abs(dev, ABS_MT_POSITION_X, value: x);
170 input_report_abs(dev, ABS_MT_POSITION_Y, value: y);
171 count++;
172 }
173 }
174
175 /* emulate single touch events when stylus is out of proximity.
176 * This is to make single touch backward support consistent
177 * across all Wacom single touch devices.
178 */
179 if (w8001->type != BTN_TOOL_PEN &&
180 w8001->type != BTN_TOOL_RUBBER) {
181 w8001->type = count == 1 ? BTN_TOOL_FINGER : KEY_RESERVED;
182 input_mt_report_pointer_emulation(dev, use_count: true);
183 }
184
185 input_sync(dev);
186}
187
188static void parse_touchquery(u8 *data, struct w8001_touch_query *query)
189{
190 memset(query, 0, sizeof(*query));
191
192 query->panel_res = data[1];
193 query->sensor_id = data[2] & 0x7;
194 query->capacity_res = data[7];
195
196 query->x = data[3] << 9;
197 query->x |= data[4] << 2;
198 query->x |= (data[2] >> 5) & 0x3;
199
200 query->y = data[5] << 9;
201 query->y |= data[6] << 2;
202 query->y |= (data[2] >> 3) & 0x3;
203
204 /* Early days' single-finger touch models need the following defaults */
205 if (!query->x && !query->y) {
206 query->x = 1024;
207 query->y = 1024;
208 if (query->panel_res)
209 query->x = query->y = (1 << query->panel_res);
210 query->panel_res = W8001_TOUCH_RESOLUTION;
211 }
212}
213
214static void report_pen_events(struct w8001 *w8001, struct w8001_coord *coord)
215{
216 struct input_dev *dev = w8001->pen_dev;
217
218 /*
219 * We have 1 bit for proximity (rdy) and 3 bits for tip, side,
220 * side2/eraser. If rdy && f2 are set, this can be either pen + side2,
221 * or eraser. Assume:
222 * - if dev is already in proximity and f2 is toggled → pen + side2
223 * - if dev comes into proximity with f2 set → eraser
224 * If f2 disappears after assuming eraser, fake proximity out for
225 * eraser and in for pen.
226 */
227
228 switch (w8001->type) {
229 case BTN_TOOL_RUBBER:
230 if (!coord->f2) {
231 input_report_abs(dev, ABS_PRESSURE, value: 0);
232 input_report_key(dev, BTN_TOUCH, value: 0);
233 input_report_key(dev, BTN_STYLUS, value: 0);
234 input_report_key(dev, BTN_STYLUS2, value: 0);
235 input_report_key(dev, BTN_TOOL_RUBBER, value: 0);
236 input_sync(dev);
237 w8001->type = BTN_TOOL_PEN;
238 }
239 break;
240
241 case BTN_TOOL_FINGER:
242 case KEY_RESERVED:
243 w8001->type = coord->f2 ? BTN_TOOL_RUBBER : BTN_TOOL_PEN;
244 break;
245
246 default:
247 input_report_key(dev, BTN_STYLUS2, value: coord->f2);
248 break;
249 }
250
251 input_report_abs(dev, ABS_X, value: coord->x);
252 input_report_abs(dev, ABS_Y, value: coord->y);
253 input_report_abs(dev, ABS_PRESSURE, value: coord->pen_pressure);
254 input_report_key(dev, BTN_TOUCH, value: coord->tsw);
255 input_report_key(dev, BTN_STYLUS, value: coord->f1);
256 input_report_key(dev, code: w8001->type, value: coord->rdy);
257 input_sync(dev);
258
259 if (!coord->rdy)
260 w8001->type = KEY_RESERVED;
261}
262
263static void report_single_touch(struct w8001 *w8001, struct w8001_coord *coord)
264{
265 struct input_dev *dev = w8001->touch_dev;
266 unsigned int x = coord->x;
267 unsigned int y = coord->y;
268
269 /* scale to pen maximum */
270 scale_touch_coordinates(w8001, x: &x, y: &y);
271
272 input_report_abs(dev, ABS_X, value: x);
273 input_report_abs(dev, ABS_Y, value: y);
274 input_report_key(dev, BTN_TOUCH, value: coord->tsw);
275
276 input_sync(dev);
277
278 w8001->type = coord->tsw ? BTN_TOOL_FINGER : KEY_RESERVED;
279}
280
281static irqreturn_t w8001_interrupt(struct serio *serio,
282 unsigned char data, unsigned int flags)
283{
284 struct w8001 *w8001 = serio_get_drvdata(serio);
285 struct w8001_coord coord;
286 unsigned char tmp;
287
288 w8001->data[w8001->idx] = data;
289 switch (w8001->idx++) {
290 case 0:
291 if ((data & W8001_LEAD_MASK) != W8001_LEAD_BYTE) {
292 pr_debug("w8001: unsynchronized data: 0x%02x\n", data);
293 w8001->idx = 0;
294 }
295 break;
296
297 case W8001_PKTLEN_TOUCH93 - 1:
298 case W8001_PKTLEN_TOUCH9A - 1:
299 tmp = w8001->data[0] & W8001_TOUCH_BYTE;
300 if (tmp != W8001_TOUCH_BYTE)
301 break;
302
303 if (w8001->pktlen == w8001->idx) {
304 w8001->idx = 0;
305 if (w8001->type != BTN_TOOL_PEN &&
306 w8001->type != BTN_TOOL_RUBBER) {
307 parse_single_touch(data: w8001->data, coord: &coord);
308 report_single_touch(w8001, coord: &coord);
309 }
310 }
311 break;
312
313 /* Pen coordinates packet */
314 case W8001_PKTLEN_TPCPEN - 1:
315 tmp = w8001->data[0] & W8001_TAB_MASK;
316 if (unlikely(tmp == W8001_TAB_BYTE))
317 break;
318
319 tmp = w8001->data[0] & W8001_TOUCH_BYTE;
320 if (tmp == W8001_TOUCH_BYTE)
321 break;
322
323 w8001->idx = 0;
324 parse_pen_data(data: w8001->data, coord: &coord);
325 report_pen_events(w8001, coord: &coord);
326 break;
327
328 /* control packet */
329 case W8001_PKTLEN_TPCCTL - 1:
330 tmp = w8001->data[0] & W8001_TOUCH_MASK;
331 if (tmp == W8001_TOUCH_BYTE)
332 break;
333
334 w8001->idx = 0;
335 memcpy(w8001->response, w8001->data, W8001_MAX_LENGTH);
336 w8001->response_type = W8001_QUERY_PACKET;
337 complete(&w8001->cmd_done);
338 break;
339
340 /* 2 finger touch packet */
341 case W8001_PKTLEN_TOUCH2FG - 1:
342 w8001->idx = 0;
343 parse_multi_touch(w8001);
344 break;
345
346 default:
347 /*
348 * ThinkPad X60 Tablet PC (pen only device) sometimes
349 * sends invalid data packets that are larger than
350 * W8001_PKTLEN_TPCPEN. Let's start over again.
351 */
352 if (!w8001->touch_dev && w8001->idx > W8001_PKTLEN_TPCPEN - 1)
353 w8001->idx = 0;
354 }
355
356 return IRQ_HANDLED;
357}
358
359static int w8001_command(struct w8001 *w8001, unsigned char command,
360 bool wait_response)
361{
362 int rc;
363
364 w8001->response_type = 0;
365 init_completion(x: &w8001->cmd_done);
366
367 rc = serio_write(serio: w8001->serio, data: command);
368 if (rc == 0 && wait_response) {
369
370 wait_for_completion_timeout(x: &w8001->cmd_done, HZ);
371 if (w8001->response_type != W8001_QUERY_PACKET)
372 rc = -EIO;
373 }
374
375 return rc;
376}
377
378static int w8001_open(struct input_dev *dev)
379{
380 struct w8001 *w8001 = input_get_drvdata(dev);
381 int err;
382
383 err = mutex_lock_interruptible(&w8001->mutex);
384 if (err)
385 return err;
386
387 if (w8001->open_count++ == 0) {
388 err = w8001_command(w8001, W8001_CMD_START, wait_response: false);
389 if (err)
390 w8001->open_count--;
391 }
392
393 mutex_unlock(lock: &w8001->mutex);
394 return err;
395}
396
397static void w8001_close(struct input_dev *dev)
398{
399 struct w8001 *w8001 = input_get_drvdata(dev);
400
401 mutex_lock(&w8001->mutex);
402
403 if (--w8001->open_count == 0)
404 w8001_command(w8001, W8001_CMD_STOP, wait_response: false);
405
406 mutex_unlock(lock: &w8001->mutex);
407}
408
409static int w8001_detect(struct w8001 *w8001)
410{
411 int error;
412
413 error = w8001_command(w8001, W8001_CMD_STOP, wait_response: false);
414 if (error)
415 return error;
416
417 msleep(msecs: 250); /* wait 250ms before querying the device */
418
419 return 0;
420}
421
422static int w8001_setup_pen(struct w8001 *w8001, char *basename,
423 size_t basename_sz)
424{
425 struct input_dev *dev = w8001->pen_dev;
426 struct w8001_coord coord;
427 int error;
428
429 /* penabled? */
430 error = w8001_command(w8001, W8001_CMD_QUERY, wait_response: true);
431 if (error)
432 return error;
433
434 __set_bit(EV_KEY, dev->evbit);
435 __set_bit(EV_ABS, dev->evbit);
436 __set_bit(BTN_TOUCH, dev->keybit);
437 __set_bit(BTN_TOOL_PEN, dev->keybit);
438 __set_bit(BTN_TOOL_RUBBER, dev->keybit);
439 __set_bit(BTN_STYLUS, dev->keybit);
440 __set_bit(BTN_STYLUS2, dev->keybit);
441 __set_bit(INPUT_PROP_DIRECT, dev->propbit);
442
443 parse_pen_data(data: w8001->response, coord: &coord);
444 w8001->max_pen_x = coord.x;
445 w8001->max_pen_y = coord.y;
446
447 input_set_abs_params(dev, ABS_X, min: 0, max: coord.x, fuzz: 0, flat: 0);
448 input_set_abs_params(dev, ABS_Y, min: 0, max: coord.y, fuzz: 0, flat: 0);
449 input_abs_set_res(dev, ABS_X, W8001_PEN_RESOLUTION);
450 input_abs_set_res(dev, ABS_Y, W8001_PEN_RESOLUTION);
451 input_set_abs_params(dev, ABS_PRESSURE, min: 0, max: coord.pen_pressure, fuzz: 0, flat: 0);
452 if (coord.tilt_x && coord.tilt_y) {
453 input_set_abs_params(dev, ABS_TILT_X, min: 0, max: coord.tilt_x, fuzz: 0, flat: 0);
454 input_set_abs_params(dev, ABS_TILT_Y, min: 0, max: coord.tilt_y, fuzz: 0, flat: 0);
455 }
456
457 w8001->id = 0x90;
458 strlcat(p: basename, q: " Penabled", avail: basename_sz);
459
460 return 0;
461}
462
463static int w8001_setup_touch(struct w8001 *w8001, char *basename,
464 size_t basename_sz)
465{
466 struct input_dev *dev = w8001->touch_dev;
467 struct w8001_touch_query touch;
468 int error;
469
470
471 /* Touch enabled? */
472 error = w8001_command(w8001, W8001_CMD_TOUCHQUERY, wait_response: true);
473 if (error)
474 return error;
475 /*
476 * Some non-touch devices may reply to the touch query. But their
477 * second byte is empty, which indicates touch is not supported.
478 */
479 if (!w8001->response[1])
480 return -ENXIO;
481
482 __set_bit(EV_KEY, dev->evbit);
483 __set_bit(EV_ABS, dev->evbit);
484 __set_bit(BTN_TOUCH, dev->keybit);
485 __set_bit(INPUT_PROP_DIRECT, dev->propbit);
486
487 parse_touchquery(data: w8001->response, query: &touch);
488 w8001->max_touch_x = touch.x;
489 w8001->max_touch_y = touch.y;
490
491 if (w8001->max_pen_x && w8001->max_pen_y) {
492 /* if pen is supported scale to pen maximum */
493 touch.x = w8001->max_pen_x;
494 touch.y = w8001->max_pen_y;
495 touch.panel_res = W8001_PEN_RESOLUTION;
496 }
497
498 input_set_abs_params(dev, ABS_X, min: 0, max: touch.x, fuzz: 0, flat: 0);
499 input_set_abs_params(dev, ABS_Y, min: 0, max: touch.y, fuzz: 0, flat: 0);
500 input_abs_set_res(dev, ABS_X, val: touch.panel_res);
501 input_abs_set_res(dev, ABS_Y, val: touch.panel_res);
502
503 switch (touch.sensor_id) {
504 case 0:
505 case 2:
506 w8001->pktlen = W8001_PKTLEN_TOUCH93;
507 w8001->id = 0x93;
508 strlcat(p: basename, q: " 1FG", avail: basename_sz);
509 break;
510
511 case 1:
512 case 3:
513 case 4:
514 w8001->pktlen = W8001_PKTLEN_TOUCH9A;
515 strlcat(p: basename, q: " 1FG", avail: basename_sz);
516 w8001->id = 0x9a;
517 break;
518
519 case 5:
520 w8001->pktlen = W8001_PKTLEN_TOUCH2FG;
521
522 __set_bit(BTN_TOOL_DOUBLETAP, dev->keybit);
523 error = input_mt_init_slots(dev, num_slots: 2, flags: 0);
524 if (error) {
525 dev_err(&w8001->serio->dev,
526 "failed to initialize MT slots: %d\n", error);
527 return error;
528 }
529
530 input_set_abs_params(dev, ABS_MT_POSITION_X,
531 min: 0, max: touch.x, fuzz: 0, flat: 0);
532 input_set_abs_params(dev, ABS_MT_POSITION_Y,
533 min: 0, max: touch.y, fuzz: 0, flat: 0);
534 input_set_abs_params(dev, ABS_MT_TOOL_TYPE,
535 min: 0, MT_TOOL_MAX, fuzz: 0, flat: 0);
536 input_abs_set_res(dev, ABS_MT_POSITION_X, val: touch.panel_res);
537 input_abs_set_res(dev, ABS_MT_POSITION_Y, val: touch.panel_res);
538
539 strlcat(p: basename, q: " 2FG", avail: basename_sz);
540 if (w8001->max_pen_x && w8001->max_pen_y)
541 w8001->id = 0xE3;
542 else
543 w8001->id = 0xE2;
544 break;
545 }
546
547 strlcat(p: basename, q: " Touchscreen", avail: basename_sz);
548
549 return 0;
550}
551
552static void w8001_set_devdata(struct input_dev *dev, struct w8001 *w8001,
553 struct serio *serio)
554{
555 dev->phys = w8001->phys;
556 dev->id.bustype = BUS_RS232;
557 dev->id.product = w8001->id;
558 dev->id.vendor = 0x056a;
559 dev->id.version = 0x0100;
560 dev->open = w8001_open;
561 dev->close = w8001_close;
562
563 dev->dev.parent = &serio->dev;
564
565 input_set_drvdata(dev, data: w8001);
566}
567
568/*
569 * w8001_disconnect() is the opposite of w8001_connect()
570 */
571
572static void w8001_disconnect(struct serio *serio)
573{
574 struct w8001 *w8001 = serio_get_drvdata(serio);
575
576 serio_close(serio);
577
578 if (w8001->pen_dev)
579 input_unregister_device(w8001->pen_dev);
580 if (w8001->touch_dev)
581 input_unregister_device(w8001->touch_dev);
582 kfree(objp: w8001);
583
584 serio_set_drvdata(serio, NULL);
585}
586
587/*
588 * w8001_connect() is the routine that is called when someone adds a
589 * new serio device that supports the w8001 protocol and registers it as
590 * an input device.
591 */
592
593static int w8001_connect(struct serio *serio, struct serio_driver *drv)
594{
595 struct w8001 *w8001;
596 struct input_dev *input_dev_pen;
597 struct input_dev *input_dev_touch;
598 char basename[64];
599 int err, err_pen, err_touch;
600
601 w8001 = kzalloc(size: sizeof(struct w8001), GFP_KERNEL);
602 input_dev_pen = input_allocate_device();
603 input_dev_touch = input_allocate_device();
604 if (!w8001 || !input_dev_pen || !input_dev_touch) {
605 err = -ENOMEM;
606 goto fail1;
607 }
608
609 w8001->serio = serio;
610 w8001->pen_dev = input_dev_pen;
611 w8001->touch_dev = input_dev_touch;
612 mutex_init(&w8001->mutex);
613 init_completion(x: &w8001->cmd_done);
614 snprintf(buf: w8001->phys, size: sizeof(w8001->phys), fmt: "%s/input0", serio->phys);
615
616 serio_set_drvdata(serio, data: w8001);
617 err = serio_open(serio, drv);
618 if (err)
619 goto fail2;
620
621 err = w8001_detect(w8001);
622 if (err)
623 goto fail3;
624
625 /* For backwards-compatibility we compose the basename based on
626 * capabilities and then just append the tool type
627 */
628 strscpy(p: basename, q: "Wacom Serial", size: sizeof(basename));
629
630 err_pen = w8001_setup_pen(w8001, basename, basename_sz: sizeof(basename));
631 err_touch = w8001_setup_touch(w8001, basename, basename_sz: sizeof(basename));
632 if (err_pen && err_touch) {
633 err = -ENXIO;
634 goto fail3;
635 }
636
637 if (!err_pen) {
638 strscpy(p: w8001->pen_name, q: basename, size: sizeof(w8001->pen_name));
639 strlcat(p: w8001->pen_name, q: " Pen", avail: sizeof(w8001->pen_name));
640 input_dev_pen->name = w8001->pen_name;
641
642 w8001_set_devdata(dev: input_dev_pen, w8001, serio);
643
644 err = input_register_device(w8001->pen_dev);
645 if (err)
646 goto fail3;
647 } else {
648 input_free_device(dev: input_dev_pen);
649 input_dev_pen = NULL;
650 w8001->pen_dev = NULL;
651 }
652
653 if (!err_touch) {
654 strscpy(p: w8001->touch_name, q: basename, size: sizeof(w8001->touch_name));
655 strlcat(p: w8001->touch_name, q: " Finger",
656 avail: sizeof(w8001->touch_name));
657 input_dev_touch->name = w8001->touch_name;
658
659 w8001_set_devdata(dev: input_dev_touch, w8001, serio);
660
661 err = input_register_device(w8001->touch_dev);
662 if (err)
663 goto fail4;
664 } else {
665 input_free_device(dev: input_dev_touch);
666 input_dev_touch = NULL;
667 w8001->touch_dev = NULL;
668 }
669
670 return 0;
671
672fail4:
673 if (w8001->pen_dev)
674 input_unregister_device(w8001->pen_dev);
675fail3:
676 serio_close(serio);
677fail2:
678 serio_set_drvdata(serio, NULL);
679fail1:
680 input_free_device(dev: input_dev_pen);
681 input_free_device(dev: input_dev_touch);
682 kfree(objp: w8001);
683 return err;
684}
685
686static const struct serio_device_id w8001_serio_ids[] = {
687 {
688 .type = SERIO_RS232,
689 .proto = SERIO_W8001,
690 .id = SERIO_ANY,
691 .extra = SERIO_ANY,
692 },
693 { 0 }
694};
695
696MODULE_DEVICE_TABLE(serio, w8001_serio_ids);
697
698static struct serio_driver w8001_drv = {
699 .driver = {
700 .name = "w8001",
701 },
702 .description = DRIVER_DESC,
703 .id_table = w8001_serio_ids,
704 .interrupt = w8001_interrupt,
705 .connect = w8001_connect,
706 .disconnect = w8001_disconnect,
707};
708
709module_serio_driver(w8001_drv);
710

source code of linux/drivers/input/touchscreen/wacom_w8001.c