1 /*
2 * Copyright (C) 2012-2013 MundoReader S.L.
3 * Author: Heiko Stuebner <heiko@sntech.de>
4 *
5 * based in parts on Nook zforce driver
6 *
7 * Copyright (C) 2010 Barnes & Noble, Inc.
8 * Author: Pieter Truter<ptruter@intrinsyc.com>
9 *
10 * This software is licensed under the terms of the GNU General Public
11 * License version 2, as published by the Free Software Foundation, and
12 * may be copied, distributed, and modified under those terms.
13 *
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
18 */
19
20 #include <linux/module.h>
21 #include <linux/hrtimer.h>
22 #include <linux/slab.h>
23 #include <linux/input.h>
24 #include <linux/interrupt.h>
25 #include <linux/i2c.h>
26 #include <linux/delay.h>
27 #include <linux/gpio/consumer.h>
28 #include <linux/device.h>
29 #include <linux/sysfs.h>
30 #include <linux/input/mt.h>
31 #include <linux/platform_data/zforce_ts.h>
32 #include <linux/regulator/consumer.h>
33 #include <linux/of.h>
34
35 #define WAIT_TIMEOUT msecs_to_jiffies(1000)
36
37 #define FRAME_START 0xee
38 #define FRAME_MAXSIZE 257
39
40 /* Offsets of the different parts of the payload the controller sends */
41 #define PAYLOAD_HEADER 0
42 #define PAYLOAD_LENGTH 1
43 #define PAYLOAD_BODY 2
44
45 /* Response offsets */
46 #define RESPONSE_ID 0
47 #define RESPONSE_DATA 1
48
49 /* Commands */
50 #define COMMAND_DEACTIVATE 0x00
51 #define COMMAND_INITIALIZE 0x01
52 #define COMMAND_RESOLUTION 0x02
53 #define COMMAND_SETCONFIG 0x03
54 #define COMMAND_DATAREQUEST 0x04
55 #define COMMAND_SCANFREQ 0x08
56 #define COMMAND_STATUS 0X1e
57
58 /*
59 * Responses the controller sends as a result of
60 * command requests
61 */
62 #define RESPONSE_DEACTIVATE 0x00
63 #define RESPONSE_INITIALIZE 0x01
64 #define RESPONSE_RESOLUTION 0x02
65 #define RESPONSE_SETCONFIG 0x03
66 #define RESPONSE_SCANFREQ 0x08
67 #define RESPONSE_STATUS 0X1e
68
69 /*
70 * Notifications are sent by the touch controller without
71 * being requested by the driver and include for example
72 * touch indications
73 */
74 #define NOTIFICATION_TOUCH 0x04
75 #define NOTIFICATION_BOOTCOMPLETE 0x07
76 #define NOTIFICATION_OVERRUN 0x25
77 #define NOTIFICATION_PROXIMITY 0x26
78 #define NOTIFICATION_INVALID_COMMAND 0xfe
79
80 #define ZFORCE_REPORT_POINTS 2
81 #define ZFORCE_MAX_AREA 0xff
82
83 #define STATE_DOWN 0
84 #define STATE_MOVE 1
85 #define STATE_UP 2
86
87 #define SETCONFIG_DUALTOUCH (1 << 0)
88
89 struct zforce_point {
90 int coord_x;
91 int coord_y;
92 int state;
93 int id;
94 int area_major;
95 int area_minor;
96 int orientation;
97 int pressure;
98 int prblty;
99 };
100
101 /*
102 * @client the i2c_client
103 * @input the input device
104 * @suspending in the process of going to suspend (don't emit wakeup
105 * events for commands executed to suspend the device)
106 * @suspended device suspended
107 * @access_mutex serialize i2c-access, to keep multipart reads together
108 * @command_done completion to wait for the command result
109 * @command_mutex serialize commands sent to the ic
110 * @command_waiting the id of the command that is currently waiting
111 * for a result
112 * @command_result returned result of the command
113 */
114 struct zforce_ts {
115 struct i2c_client *client;
116 struct input_dev *input;
117 const struct zforce_ts_platdata *pdata;
118 char phys[32];
119
120 struct regulator *reg_vdd;
121
122 struct gpio_desc *gpio_int;
123 struct gpio_desc *gpio_rst;
124
125 bool suspending;
126 bool suspended;
127 bool boot_complete;
128
129 /* Firmware version information */
130 u16 version_major;
131 u16 version_minor;
132 u16 version_build;
133 u16 version_rev;
134
135 struct mutex access_mutex;
136
137 struct completion command_done;
138 struct mutex command_mutex;
139 int command_waiting;
140 int command_result;
141 };
142
zforce_command(struct zforce_ts * ts,u8 cmd)143 static int zforce_command(struct zforce_ts *ts, u8 cmd)
144 {
145 struct i2c_client *client = ts->client;
146 char buf[3];
147 int ret;
148
149 dev_dbg(&client->dev, "%s: 0x%x\n", __func__, cmd);
150
151 buf[0] = FRAME_START;
152 buf[1] = 1; /* data size, command only */
153 buf[2] = cmd;
154
155 mutex_lock(&ts->access_mutex);
156 ret = i2c_master_send(client, &buf[0], ARRAY_SIZE(buf));
157 mutex_unlock(&ts->access_mutex);
158 if (ret < 0) {
159 dev_err(&client->dev, "i2c send data request error: %d\n", ret);
160 return ret;
161 }
162
163 return 0;
164 }
165
zforce_reset_assert(struct zforce_ts * ts)166 static void zforce_reset_assert(struct zforce_ts *ts)
167 {
168 gpiod_set_value_cansleep(ts->gpio_rst, 1);
169 }
170
zforce_reset_deassert(struct zforce_ts * ts)171 static void zforce_reset_deassert(struct zforce_ts *ts)
172 {
173 gpiod_set_value_cansleep(ts->gpio_rst, 0);
174 }
175
zforce_send_wait(struct zforce_ts * ts,const char * buf,int len)176 static int zforce_send_wait(struct zforce_ts *ts, const char *buf, int len)
177 {
178 struct i2c_client *client = ts->client;
179 int ret;
180
181 ret = mutex_trylock(&ts->command_mutex);
182 if (!ret) {
183 dev_err(&client->dev, "already waiting for a command\n");
184 return -EBUSY;
185 }
186
187 dev_dbg(&client->dev, "sending %d bytes for command 0x%x\n",
188 buf[1], buf[2]);
189
190 ts->command_waiting = buf[2];
191
192 mutex_lock(&ts->access_mutex);
193 ret = i2c_master_send(client, buf, len);
194 mutex_unlock(&ts->access_mutex);
195 if (ret < 0) {
196 dev_err(&client->dev, "i2c send data request error: %d\n", ret);
197 goto unlock;
198 }
199
200 dev_dbg(&client->dev, "waiting for result for command 0x%x\n", buf[2]);
201
202 if (wait_for_completion_timeout(&ts->command_done, WAIT_TIMEOUT) == 0) {
203 ret = -ETIME;
204 goto unlock;
205 }
206
207 ret = ts->command_result;
208
209 unlock:
210 mutex_unlock(&ts->command_mutex);
211 return ret;
212 }
213
zforce_command_wait(struct zforce_ts * ts,u8 cmd)214 static int zforce_command_wait(struct zforce_ts *ts, u8 cmd)
215 {
216 struct i2c_client *client = ts->client;
217 char buf[3];
218 int ret;
219
220 dev_dbg(&client->dev, "%s: 0x%x\n", __func__, cmd);
221
222 buf[0] = FRAME_START;
223 buf[1] = 1; /* data size, command only */
224 buf[2] = cmd;
225
226 ret = zforce_send_wait(ts, &buf[0], ARRAY_SIZE(buf));
227 if (ret < 0) {
228 dev_err(&client->dev, "i2c send data request error: %d\n", ret);
229 return ret;
230 }
231
232 return 0;
233 }
234
zforce_resolution(struct zforce_ts * ts,u16 x,u16 y)235 static int zforce_resolution(struct zforce_ts *ts, u16 x, u16 y)
236 {
237 struct i2c_client *client = ts->client;
238 char buf[7] = { FRAME_START, 5, COMMAND_RESOLUTION,
239 (x & 0xff), ((x >> 8) & 0xff),
240 (y & 0xff), ((y >> 8) & 0xff) };
241
242 dev_dbg(&client->dev, "set resolution to (%d,%d)\n", x, y);
243
244 return zforce_send_wait(ts, &buf[0], ARRAY_SIZE(buf));
245 }
246
zforce_scan_frequency(struct zforce_ts * ts,u16 idle,u16 finger,u16 stylus)247 static int zforce_scan_frequency(struct zforce_ts *ts, u16 idle, u16 finger,
248 u16 stylus)
249 {
250 struct i2c_client *client = ts->client;
251 char buf[9] = { FRAME_START, 7, COMMAND_SCANFREQ,
252 (idle & 0xff), ((idle >> 8) & 0xff),
253 (finger & 0xff), ((finger >> 8) & 0xff),
254 (stylus & 0xff), ((stylus >> 8) & 0xff) };
255
256 dev_dbg(&client->dev,
257 "set scan frequency to (idle: %d, finger: %d, stylus: %d)\n",
258 idle, finger, stylus);
259
260 return zforce_send_wait(ts, &buf[0], ARRAY_SIZE(buf));
261 }
262
zforce_setconfig(struct zforce_ts * ts,char b1)263 static int zforce_setconfig(struct zforce_ts *ts, char b1)
264 {
265 struct i2c_client *client = ts->client;
266 char buf[7] = { FRAME_START, 5, COMMAND_SETCONFIG,
267 b1, 0, 0, 0 };
268
269 dev_dbg(&client->dev, "set config to (%d)\n", b1);
270
271 return zforce_send_wait(ts, &buf[0], ARRAY_SIZE(buf));
272 }
273
zforce_start(struct zforce_ts * ts)274 static int zforce_start(struct zforce_ts *ts)
275 {
276 struct i2c_client *client = ts->client;
277 const struct zforce_ts_platdata *pdata = ts->pdata;
278 int ret;
279
280 dev_dbg(&client->dev, "starting device\n");
281
282 ret = zforce_command_wait(ts, COMMAND_INITIALIZE);
283 if (ret) {
284 dev_err(&client->dev, "Unable to initialize, %d\n", ret);
285 return ret;
286 }
287
288 ret = zforce_resolution(ts, pdata->x_max, pdata->y_max);
289 if (ret) {
290 dev_err(&client->dev, "Unable to set resolution, %d\n", ret);
291 goto error;
292 }
293
294 ret = zforce_scan_frequency(ts, 10, 50, 50);
295 if (ret) {
296 dev_err(&client->dev, "Unable to set scan frequency, %d\n",
297 ret);
298 goto error;
299 }
300
301 ret = zforce_setconfig(ts, SETCONFIG_DUALTOUCH);
302 if (ret) {
303 dev_err(&client->dev, "Unable to set config\n");
304 goto error;
305 }
306
307 /* start sending touch events */
308 ret = zforce_command(ts, COMMAND_DATAREQUEST);
309 if (ret) {
310 dev_err(&client->dev, "Unable to request data\n");
311 goto error;
312 }
313
314 /*
315 * Per NN, initial cal. take max. of 200msec.
316 * Allow time to complete this calibration
317 */
318 msleep(200);
319
320 return 0;
321
322 error:
323 zforce_command_wait(ts, COMMAND_DEACTIVATE);
324 return ret;
325 }
326
zforce_stop(struct zforce_ts * ts)327 static int zforce_stop(struct zforce_ts *ts)
328 {
329 struct i2c_client *client = ts->client;
330 int ret;
331
332 dev_dbg(&client->dev, "stopping device\n");
333
334 /* Deactivates touch sensing and puts the device into sleep. */
335 ret = zforce_command_wait(ts, COMMAND_DEACTIVATE);
336 if (ret != 0) {
337 dev_err(&client->dev, "could not deactivate device, %d\n",
338 ret);
339 return ret;
340 }
341
342 return 0;
343 }
344
zforce_touch_event(struct zforce_ts * ts,u8 * payload)345 static int zforce_touch_event(struct zforce_ts *ts, u8 *payload)
346 {
347 struct i2c_client *client = ts->client;
348 const struct zforce_ts_platdata *pdata = ts->pdata;
349 struct zforce_point point;
350 int count, i, num = 0;
351
352 count = payload[0];
353 if (count > ZFORCE_REPORT_POINTS) {
354 dev_warn(&client->dev,
355 "too many coordinates %d, expected max %d\n",
356 count, ZFORCE_REPORT_POINTS);
357 count = ZFORCE_REPORT_POINTS;
358 }
359
360 for (i = 0; i < count; i++) {
361 point.coord_x =
362 payload[9 * i + 2] << 8 | payload[9 * i + 1];
363 point.coord_y =
364 payload[9 * i + 4] << 8 | payload[9 * i + 3];
365
366 if (point.coord_x > pdata->x_max ||
367 point.coord_y > pdata->y_max) {
368 dev_warn(&client->dev, "coordinates (%d,%d) invalid\n",
369 point.coord_x, point.coord_y);
370 point.coord_x = point.coord_y = 0;
371 }
372
373 point.state = payload[9 * i + 5] & 0x0f;
374 point.id = (payload[9 * i + 5] & 0xf0) >> 4;
375
376 /* determine touch major, minor and orientation */
377 point.area_major = max(payload[9 * i + 6],
378 payload[9 * i + 7]);
379 point.area_minor = min(payload[9 * i + 6],
380 payload[9 * i + 7]);
381 point.orientation = payload[9 * i + 6] > payload[9 * i + 7];
382
383 point.pressure = payload[9 * i + 8];
384 point.prblty = payload[9 * i + 9];
385
386 dev_dbg(&client->dev,
387 "point %d/%d: state %d, id %d, pressure %d, prblty %d, x %d, y %d, amajor %d, aminor %d, ori %d\n",
388 i, count, point.state, point.id,
389 point.pressure, point.prblty,
390 point.coord_x, point.coord_y,
391 point.area_major, point.area_minor,
392 point.orientation);
393
394 /* the zforce id starts with "1", so needs to be decreased */
395 input_mt_slot(ts->input, point.id - 1);
396
397 input_mt_report_slot_state(ts->input, MT_TOOL_FINGER,
398 point.state != STATE_UP);
399
400 if (point.state != STATE_UP) {
401 input_report_abs(ts->input, ABS_MT_POSITION_X,
402 point.coord_x);
403 input_report_abs(ts->input, ABS_MT_POSITION_Y,
404 point.coord_y);
405 input_report_abs(ts->input, ABS_MT_TOUCH_MAJOR,
406 point.area_major);
407 input_report_abs(ts->input, ABS_MT_TOUCH_MINOR,
408 point.area_minor);
409 input_report_abs(ts->input, ABS_MT_ORIENTATION,
410 point.orientation);
411 num++;
412 }
413 }
414
415 input_mt_sync_frame(ts->input);
416
417 input_mt_report_finger_count(ts->input, num);
418
419 input_sync(ts->input);
420
421 return 0;
422 }
423
zforce_read_packet(struct zforce_ts * ts,u8 * buf)424 static int zforce_read_packet(struct zforce_ts *ts, u8 *buf)
425 {
426 struct i2c_client *client = ts->client;
427 int ret;
428
429 mutex_lock(&ts->access_mutex);
430
431 /* read 2 byte message header */
432 ret = i2c_master_recv(client, buf, 2);
433 if (ret < 0) {
434 dev_err(&client->dev, "error reading header: %d\n", ret);
435 goto unlock;
436 }
437
438 if (buf[PAYLOAD_HEADER] != FRAME_START) {
439 dev_err(&client->dev, "invalid frame start: %d\n", buf[0]);
440 ret = -EIO;
441 goto unlock;
442 }
443
444 if (buf[PAYLOAD_LENGTH] == 0) {
445 dev_err(&client->dev, "invalid payload length: %d\n",
446 buf[PAYLOAD_LENGTH]);
447 ret = -EIO;
448 goto unlock;
449 }
450
451 /* read the message */
452 ret = i2c_master_recv(client, &buf[PAYLOAD_BODY], buf[PAYLOAD_LENGTH]);
453 if (ret < 0) {
454 dev_err(&client->dev, "error reading payload: %d\n", ret);
455 goto unlock;
456 }
457
458 dev_dbg(&client->dev, "read %d bytes for response command 0x%x\n",
459 buf[PAYLOAD_LENGTH], buf[PAYLOAD_BODY]);
460
461 unlock:
462 mutex_unlock(&ts->access_mutex);
463 return ret;
464 }
465
zforce_complete(struct zforce_ts * ts,int cmd,int result)466 static void zforce_complete(struct zforce_ts *ts, int cmd, int result)
467 {
468 struct i2c_client *client = ts->client;
469
470 if (ts->command_waiting == cmd) {
471 dev_dbg(&client->dev, "completing command 0x%x\n", cmd);
472 ts->command_result = result;
473 complete(&ts->command_done);
474 } else {
475 dev_dbg(&client->dev, "command %d not for us\n", cmd);
476 }
477 }
478
zforce_irq(int irq,void * dev_id)479 static irqreturn_t zforce_irq(int irq, void *dev_id)
480 {
481 struct zforce_ts *ts = dev_id;
482 struct i2c_client *client = ts->client;
483
484 if (ts->suspended && device_may_wakeup(&client->dev))
485 pm_wakeup_event(&client->dev, 500);
486
487 return IRQ_WAKE_THREAD;
488 }
489
zforce_irq_thread(int irq,void * dev_id)490 static irqreturn_t zforce_irq_thread(int irq, void *dev_id)
491 {
492 struct zforce_ts *ts = dev_id;
493 struct i2c_client *client = ts->client;
494 int ret;
495 u8 payload_buffer[FRAME_MAXSIZE];
496 u8 *payload;
497
498 /*
499 * When still suspended, return.
500 * Due to the level-interrupt we will get re-triggered later.
501 */
502 if (ts->suspended) {
503 msleep(20);
504 return IRQ_HANDLED;
505 }
506
507 dev_dbg(&client->dev, "handling interrupt\n");
508
509 /* Don't emit wakeup events from commands run by zforce_suspend */
510 if (!ts->suspending && device_may_wakeup(&client->dev))
511 pm_stay_awake(&client->dev);
512
513 /*
514 * Run at least once and exit the loop if
515 * - the optional interrupt GPIO isn't specified
516 * (there is only one packet read per ISR invocation, then)
517 * or
518 * - the GPIO isn't active any more
519 * (packet read until the level GPIO indicates that there is
520 * no IRQ any more)
521 */
522 do {
523 ret = zforce_read_packet(ts, payload_buffer);
524 if (ret < 0) {
525 dev_err(&client->dev,
526 "could not read packet, ret: %d\n", ret);
527 break;
528 }
529
530 payload = &payload_buffer[PAYLOAD_BODY];
531
532 switch (payload[RESPONSE_ID]) {
533 case NOTIFICATION_TOUCH:
534 /*
535 * Always report touch-events received while
536 * suspending, when being a wakeup source
537 */
538 if (ts->suspending && device_may_wakeup(&client->dev))
539 pm_wakeup_event(&client->dev, 500);
540 zforce_touch_event(ts, &payload[RESPONSE_DATA]);
541 break;
542
543 case NOTIFICATION_BOOTCOMPLETE:
544 ts->boot_complete = payload[RESPONSE_DATA];
545 zforce_complete(ts, payload[RESPONSE_ID], 0);
546 break;
547
548 case RESPONSE_INITIALIZE:
549 case RESPONSE_DEACTIVATE:
550 case RESPONSE_SETCONFIG:
551 case RESPONSE_RESOLUTION:
552 case RESPONSE_SCANFREQ:
553 zforce_complete(ts, payload[RESPONSE_ID],
554 payload[RESPONSE_DATA]);
555 break;
556
557 case RESPONSE_STATUS:
558 /*
559 * Version Payload Results
560 * [2:major] [2:minor] [2:build] [2:rev]
561 */
562 ts->version_major = (payload[RESPONSE_DATA + 1] << 8) |
563 payload[RESPONSE_DATA];
564 ts->version_minor = (payload[RESPONSE_DATA + 3] << 8) |
565 payload[RESPONSE_DATA + 2];
566 ts->version_build = (payload[RESPONSE_DATA + 5] << 8) |
567 payload[RESPONSE_DATA + 4];
568 ts->version_rev = (payload[RESPONSE_DATA + 7] << 8) |
569 payload[RESPONSE_DATA + 6];
570 dev_dbg(&ts->client->dev,
571 "Firmware Version %04x:%04x %04x:%04x\n",
572 ts->version_major, ts->version_minor,
573 ts->version_build, ts->version_rev);
574
575 zforce_complete(ts, payload[RESPONSE_ID], 0);
576 break;
577
578 case NOTIFICATION_INVALID_COMMAND:
579 dev_err(&ts->client->dev, "invalid command: 0x%x\n",
580 payload[RESPONSE_DATA]);
581 break;
582
583 default:
584 dev_err(&ts->client->dev,
585 "unrecognized response id: 0x%x\n",
586 payload[RESPONSE_ID]);
587 break;
588 }
589 } while (gpiod_get_value_cansleep(ts->gpio_int));
590
591 if (!ts->suspending && device_may_wakeup(&client->dev))
592 pm_relax(&client->dev);
593
594 dev_dbg(&client->dev, "finished interrupt\n");
595
596 return IRQ_HANDLED;
597 }
598
zforce_input_open(struct input_dev * dev)599 static int zforce_input_open(struct input_dev *dev)
600 {
601 struct zforce_ts *ts = input_get_drvdata(dev);
602
603 return zforce_start(ts);
604 }
605
zforce_input_close(struct input_dev * dev)606 static void zforce_input_close(struct input_dev *dev)
607 {
608 struct zforce_ts *ts = input_get_drvdata(dev);
609 struct i2c_client *client = ts->client;
610 int ret;
611
612 ret = zforce_stop(ts);
613 if (ret)
614 dev_warn(&client->dev, "stopping zforce failed\n");
615
616 return;
617 }
618
zforce_suspend(struct device * dev)619 static int __maybe_unused zforce_suspend(struct device *dev)
620 {
621 struct i2c_client *client = to_i2c_client(dev);
622 struct zforce_ts *ts = i2c_get_clientdata(client);
623 struct input_dev *input = ts->input;
624 int ret = 0;
625
626 mutex_lock(&input->mutex);
627 ts->suspending = true;
628
629 /*
630 * When configured as a wakeup source device should always wake
631 * the system, therefore start device if necessary.
632 */
633 if (device_may_wakeup(&client->dev)) {
634 dev_dbg(&client->dev, "suspend while being a wakeup source\n");
635
636 /* Need to start device, if not open, to be a wakeup source. */
637 if (!input->users) {
638 ret = zforce_start(ts);
639 if (ret)
640 goto unlock;
641 }
642
643 enable_irq_wake(client->irq);
644 } else if (input->users) {
645 dev_dbg(&client->dev,
646 "suspend without being a wakeup source\n");
647
648 ret = zforce_stop(ts);
649 if (ret)
650 goto unlock;
651
652 disable_irq(client->irq);
653 }
654
655 ts->suspended = true;
656
657 unlock:
658 ts->suspending = false;
659 mutex_unlock(&input->mutex);
660
661 return ret;
662 }
663
zforce_resume(struct device * dev)664 static int __maybe_unused zforce_resume(struct device *dev)
665 {
666 struct i2c_client *client = to_i2c_client(dev);
667 struct zforce_ts *ts = i2c_get_clientdata(client);
668 struct input_dev *input = ts->input;
669 int ret = 0;
670
671 mutex_lock(&input->mutex);
672
673 ts->suspended = false;
674
675 if (device_may_wakeup(&client->dev)) {
676 dev_dbg(&client->dev, "resume from being a wakeup source\n");
677
678 disable_irq_wake(client->irq);
679
680 /* need to stop device if it was not open on suspend */
681 if (!input->users) {
682 ret = zforce_stop(ts);
683 if (ret)
684 goto unlock;
685 }
686 } else if (input->users) {
687 dev_dbg(&client->dev, "resume without being a wakeup source\n");
688
689 enable_irq(client->irq);
690
691 ret = zforce_start(ts);
692 if (ret < 0)
693 goto unlock;
694 }
695
696 unlock:
697 mutex_unlock(&input->mutex);
698
699 return ret;
700 }
701
702 static SIMPLE_DEV_PM_OPS(zforce_pm_ops, zforce_suspend, zforce_resume);
703
zforce_reset(void * data)704 static void zforce_reset(void *data)
705 {
706 struct zforce_ts *ts = data;
707
708 zforce_reset_assert(ts);
709
710 udelay(10);
711
712 if (!IS_ERR(ts->reg_vdd))
713 regulator_disable(ts->reg_vdd);
714 }
715
zforce_parse_dt(struct device * dev)716 static struct zforce_ts_platdata *zforce_parse_dt(struct device *dev)
717 {
718 struct zforce_ts_platdata *pdata;
719 struct device_node *np = dev->of_node;
720
721 if (!np)
722 return ERR_PTR(-ENOENT);
723
724 pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
725 if (!pdata) {
726 dev_err(dev, "failed to allocate platform data\n");
727 return ERR_PTR(-ENOMEM);
728 }
729
730 if (of_property_read_u32(np, "x-size", &pdata->x_max)) {
731 dev_err(dev, "failed to get x-size property\n");
732 return ERR_PTR(-EINVAL);
733 }
734
735 if (of_property_read_u32(np, "y-size", &pdata->y_max)) {
736 dev_err(dev, "failed to get y-size property\n");
737 return ERR_PTR(-EINVAL);
738 }
739
740 return pdata;
741 }
742
zforce_probe(struct i2c_client * client,const struct i2c_device_id * id)743 static int zforce_probe(struct i2c_client *client,
744 const struct i2c_device_id *id)
745 {
746 const struct zforce_ts_platdata *pdata = dev_get_platdata(&client->dev);
747 struct zforce_ts *ts;
748 struct input_dev *input_dev;
749 int ret;
750
751 if (!pdata) {
752 pdata = zforce_parse_dt(&client->dev);
753 if (IS_ERR(pdata))
754 return PTR_ERR(pdata);
755 }
756
757 ts = devm_kzalloc(&client->dev, sizeof(struct zforce_ts), GFP_KERNEL);
758 if (!ts)
759 return -ENOMEM;
760
761 ts->gpio_rst = devm_gpiod_get_optional(&client->dev, "reset",
762 GPIOD_OUT_HIGH);
763 if (IS_ERR(ts->gpio_rst)) {
764 ret = PTR_ERR(ts->gpio_rst);
765 dev_err(&client->dev,
766 "failed to request reset GPIO: %d\n", ret);
767 return ret;
768 }
769
770 if (ts->gpio_rst) {
771 ts->gpio_int = devm_gpiod_get_optional(&client->dev, "irq",
772 GPIOD_IN);
773 if (IS_ERR(ts->gpio_int)) {
774 ret = PTR_ERR(ts->gpio_int);
775 dev_err(&client->dev,
776 "failed to request interrupt GPIO: %d\n", ret);
777 return ret;
778 }
779 } else {
780 /*
781 * Deprecated GPIO handling for compatibility
782 * with legacy binding.
783 */
784
785 /* INT GPIO */
786 ts->gpio_int = devm_gpiod_get_index(&client->dev, NULL, 0,
787 GPIOD_IN);
788 if (IS_ERR(ts->gpio_int)) {
789 ret = PTR_ERR(ts->gpio_int);
790 dev_err(&client->dev,
791 "failed to request interrupt GPIO: %d\n", ret);
792 return ret;
793 }
794
795 /* RST GPIO */
796 ts->gpio_rst = devm_gpiod_get_index(&client->dev, NULL, 1,
797 GPIOD_OUT_HIGH);
798 if (IS_ERR(ts->gpio_rst)) {
799 ret = PTR_ERR(ts->gpio_rst);
800 dev_err(&client->dev,
801 "failed to request reset GPIO: %d\n", ret);
802 return ret;
803 }
804 }
805
806 ts->reg_vdd = devm_regulator_get_optional(&client->dev, "vdd");
807 if (IS_ERR(ts->reg_vdd)) {
808 ret = PTR_ERR(ts->reg_vdd);
809 if (ret == -EPROBE_DEFER)
810 return ret;
811 } else {
812 ret = regulator_enable(ts->reg_vdd);
813 if (ret)
814 return ret;
815
816 /*
817 * according to datasheet add 100us grace time after regular
818 * regulator enable delay.
819 */
820 udelay(100);
821 }
822
823 ret = devm_add_action(&client->dev, zforce_reset, ts);
824 if (ret) {
825 dev_err(&client->dev, "failed to register reset action, %d\n",
826 ret);
827
828 /* hereafter the regulator will be disabled by the action */
829 if (!IS_ERR(ts->reg_vdd))
830 regulator_disable(ts->reg_vdd);
831
832 return ret;
833 }
834
835 snprintf(ts->phys, sizeof(ts->phys),
836 "%s/input0", dev_name(&client->dev));
837
838 input_dev = devm_input_allocate_device(&client->dev);
839 if (!input_dev) {
840 dev_err(&client->dev, "could not allocate input device\n");
841 return -ENOMEM;
842 }
843
844 mutex_init(&ts->access_mutex);
845 mutex_init(&ts->command_mutex);
846
847 ts->pdata = pdata;
848 ts->client = client;
849 ts->input = input_dev;
850
851 input_dev->name = "Neonode zForce touchscreen";
852 input_dev->phys = ts->phys;
853 input_dev->id.bustype = BUS_I2C;
854
855 input_dev->open = zforce_input_open;
856 input_dev->close = zforce_input_close;
857
858 __set_bit(EV_KEY, input_dev->evbit);
859 __set_bit(EV_SYN, input_dev->evbit);
860 __set_bit(EV_ABS, input_dev->evbit);
861
862 /* For multi touch */
863 input_set_abs_params(input_dev, ABS_MT_POSITION_X, 0,
864 pdata->x_max, 0, 0);
865 input_set_abs_params(input_dev, ABS_MT_POSITION_Y, 0,
866 pdata->y_max, 0, 0);
867
868 input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR, 0,
869 ZFORCE_MAX_AREA, 0, 0);
870 input_set_abs_params(input_dev, ABS_MT_TOUCH_MINOR, 0,
871 ZFORCE_MAX_AREA, 0, 0);
872 input_set_abs_params(input_dev, ABS_MT_ORIENTATION, 0, 1, 0, 0);
873 input_mt_init_slots(input_dev, ZFORCE_REPORT_POINTS, INPUT_MT_DIRECT);
874
875 input_set_drvdata(ts->input, ts);
876
877 init_completion(&ts->command_done);
878
879 /*
880 * The zforce pulls the interrupt low when it has data ready.
881 * After it is triggered the isr thread runs until all the available
882 * packets have been read and the interrupt is high again.
883 * Therefore we can trigger the interrupt anytime it is low and do
884 * not need to limit it to the interrupt edge.
885 */
886 ret = devm_request_threaded_irq(&client->dev, client->irq,
887 zforce_irq, zforce_irq_thread,
888 IRQF_TRIGGER_LOW | IRQF_ONESHOT,
889 input_dev->name, ts);
890 if (ret) {
891 dev_err(&client->dev, "irq %d request failed\n", client->irq);
892 return ret;
893 }
894
895 i2c_set_clientdata(client, ts);
896
897 /* let the controller boot */
898 zforce_reset_deassert(ts);
899
900 ts->command_waiting = NOTIFICATION_BOOTCOMPLETE;
901 if (wait_for_completion_timeout(&ts->command_done, WAIT_TIMEOUT) == 0)
902 dev_warn(&client->dev, "bootcomplete timed out\n");
903
904 /* need to start device to get version information */
905 ret = zforce_command_wait(ts, COMMAND_INITIALIZE);
906 if (ret) {
907 dev_err(&client->dev, "unable to initialize, %d\n", ret);
908 return ret;
909 }
910
911 /* this gets the firmware version among other information */
912 ret = zforce_command_wait(ts, COMMAND_STATUS);
913 if (ret < 0) {
914 dev_err(&client->dev, "couldn't get status, %d\n", ret);
915 zforce_stop(ts);
916 return ret;
917 }
918
919 /* stop device and put it into sleep until it is opened */
920 ret = zforce_stop(ts);
921 if (ret < 0)
922 return ret;
923
924 device_set_wakeup_capable(&client->dev, true);
925
926 ret = input_register_device(input_dev);
927 if (ret) {
928 dev_err(&client->dev, "could not register input device, %d\n",
929 ret);
930 return ret;
931 }
932
933 return 0;
934 }
935
936 static struct i2c_device_id zforce_idtable[] = {
937 { "zforce-ts", 0 },
938 { }
939 };
940 MODULE_DEVICE_TABLE(i2c, zforce_idtable);
941
942 #ifdef CONFIG_OF
943 static const struct of_device_id zforce_dt_idtable[] = {
944 { .compatible = "neonode,zforce" },
945 {},
946 };
947 MODULE_DEVICE_TABLE(of, zforce_dt_idtable);
948 #endif
949
950 static struct i2c_driver zforce_driver = {
951 .driver = {
952 .name = "zforce-ts",
953 .pm = &zforce_pm_ops,
954 .of_match_table = of_match_ptr(zforce_dt_idtable),
955 },
956 .probe = zforce_probe,
957 .id_table = zforce_idtable,
958 };
959
960 module_i2c_driver(zforce_driver);
961
962 MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>");
963 MODULE_DESCRIPTION("zForce TouchScreen Driver");
964 MODULE_LICENSE("GPL");
965