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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.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/of.h>
33#include <linux/of_gpio.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
89struct 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 */
114struct 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 bool suspending;
121 bool suspended;
122 bool boot_complete;
123
124 /* Firmware version information */
125 u16 version_major;
126 u16 version_minor;
127 u16 version_build;
128 u16 version_rev;
129
130 struct mutex access_mutex;
131
132 struct completion command_done;
133 struct mutex command_mutex;
134 int command_waiting;
135 int command_result;
136};
137
138static int zforce_command(struct zforce_ts *ts, u8 cmd)
139{
140 struct i2c_client *client = ts->client;
141 char buf[3];
142 int ret;
143
144 dev_dbg(&client->dev, "%s: 0x%x\n", __func__, cmd);
145
146 buf[0] = FRAME_START;
147 buf[1] = 1; /* data size, command only */
148 buf[2] = cmd;
149
150 mutex_lock(&ts->access_mutex);
151 ret = i2c_master_send(client, &buf[0], ARRAY_SIZE(buf));
152 mutex_unlock(&ts->access_mutex);
153 if (ret < 0) {
154 dev_err(&client->dev, "i2c send data request error: %d\n", ret);
155 return ret;
156 }
157
158 return 0;
159}
160
161static int zforce_send_wait(struct zforce_ts *ts, const char *buf, int len)
162{
163 struct i2c_client *client = ts->client;
164 int ret;
165
166 ret = mutex_trylock(&ts->command_mutex);
167 if (!ret) {
168 dev_err(&client->dev, "already waiting for a command\n");
169 return -EBUSY;
170 }
171
172 dev_dbg(&client->dev, "sending %d bytes for command 0x%x\n",
173 buf[1], buf[2]);
174
175 ts->command_waiting = buf[2];
176
177 mutex_lock(&ts->access_mutex);
178 ret = i2c_master_send(client, buf, len);
179 mutex_unlock(&ts->access_mutex);
180 if (ret < 0) {
181 dev_err(&client->dev, "i2c send data request error: %d\n", ret);
182 goto unlock;
183 }
184
185 dev_dbg(&client->dev, "waiting for result for command 0x%x\n", buf[2]);
186
187 if (wait_for_completion_timeout(&ts->command_done, WAIT_TIMEOUT) == 0) {
188 ret = -ETIME;
189 goto unlock;
190 }
191
192 ret = ts->command_result;
193
194unlock:
195 mutex_unlock(&ts->command_mutex);
196 return ret;
197}
198
199static int zforce_command_wait(struct zforce_ts *ts, u8 cmd)
200{
201 struct i2c_client *client = ts->client;
202 char buf[3];
203 int ret;
204
205 dev_dbg(&client->dev, "%s: 0x%x\n", __func__, cmd);
206
207 buf[0] = FRAME_START;
208 buf[1] = 1; /* data size, command only */
209 buf[2] = cmd;
210
211 ret = zforce_send_wait(ts, &buf[0], ARRAY_SIZE(buf));
212 if (ret < 0) {
213 dev_err(&client->dev, "i2c send data request error: %d\n", ret);
214 return ret;
215 }
216
217 return 0;
218}
219
220static int zforce_resolution(struct zforce_ts *ts, u16 x, u16 y)
221{
222 struct i2c_client *client = ts->client;
223 char buf[7] = { FRAME_START, 5, COMMAND_RESOLUTION,
224 (x & 0xff), ((x >> 8) & 0xff),
225 (y & 0xff), ((y >> 8) & 0xff) };
226
227 dev_dbg(&client->dev, "set resolution to (%d,%d)\n", x, y);
228
229 return zforce_send_wait(ts, &buf[0], ARRAY_SIZE(buf));
230}
231
232static int zforce_scan_frequency(struct zforce_ts *ts, u16 idle, u16 finger,
233 u16 stylus)
234{
235 struct i2c_client *client = ts->client;
236 char buf[9] = { FRAME_START, 7, COMMAND_SCANFREQ,
237 (idle & 0xff), ((idle >> 8) & 0xff),
238 (finger & 0xff), ((finger >> 8) & 0xff),
239 (stylus & 0xff), ((stylus >> 8) & 0xff) };
240
241 dev_dbg(&client->dev,
242 "set scan frequency to (idle: %d, finger: %d, stylus: %d)\n",
243 idle, finger, stylus);
244
245 return zforce_send_wait(ts, &buf[0], ARRAY_SIZE(buf));
246}
247
248static int zforce_setconfig(struct zforce_ts *ts, char b1)
249{
250 struct i2c_client *client = ts->client;
251 char buf[7] = { FRAME_START, 5, COMMAND_SETCONFIG,
252 b1, 0, 0, 0 };
253
254 dev_dbg(&client->dev, "set config to (%d)\n", b1);
255
256 return zforce_send_wait(ts, &buf[0], ARRAY_SIZE(buf));
257}
258
259static int zforce_start(struct zforce_ts *ts)
260{
261 struct i2c_client *client = ts->client;
262 const struct zforce_ts_platdata *pdata = ts->pdata;
263 int ret;
264
265 dev_dbg(&client->dev, "starting device\n");
266
267 ret = zforce_command_wait(ts, COMMAND_INITIALIZE);
268 if (ret) {
269 dev_err(&client->dev, "Unable to initialize, %d\n", ret);
270 return ret;
271 }
272
273 ret = zforce_resolution(ts, pdata->x_max, pdata->y_max);
274 if (ret) {
275 dev_err(&client->dev, "Unable to set resolution, %d\n", ret);
276 goto error;
277 }
278
279 ret = zforce_scan_frequency(ts, 10, 50, 50);
280 if (ret) {
281 dev_err(&client->dev, "Unable to set scan frequency, %d\n",
282 ret);
283 goto error;
284 }
285
286 ret = zforce_setconfig(ts, SETCONFIG_DUALTOUCH);
287 if (ret) {
288 dev_err(&client->dev, "Unable to set config\n");
289 goto error;
290 }
291
292 /* start sending touch events */
293 ret = zforce_command(ts, COMMAND_DATAREQUEST);
294 if (ret) {
295 dev_err(&client->dev, "Unable to request data\n");
296 goto error;
297 }
298
299 /*
300 * Per NN, initial cal. take max. of 200msec.
301 * Allow time to complete this calibration
302 */
303 msleep(200);
304
305 return 0;
306
307error:
308 zforce_command_wait(ts, COMMAND_DEACTIVATE);
309 return ret;
310}
311
312static int zforce_stop(struct zforce_ts *ts)
313{
314 struct i2c_client *client = ts->client;
315 int ret;
316
317 dev_dbg(&client->dev, "stopping device\n");
318
319 /* Deactivates touch sensing and puts the device into sleep. */
320 ret = zforce_command_wait(ts, COMMAND_DEACTIVATE);
321 if (ret != 0) {
322 dev_err(&client->dev, "could not deactivate device, %d\n",
323 ret);
324 return ret;
325 }
326
327 return 0;
328}
329
330static int zforce_touch_event(struct zforce_ts *ts, u8 *payload)
331{
332 struct i2c_client *client = ts->client;
333 const struct zforce_ts_platdata *pdata = ts->pdata;
334 struct zforce_point point;
335 int count, i, num = 0;
336
337 count = payload[0];
338 if (count > ZFORCE_REPORT_POINTS) {
339 dev_warn(&client->dev,
340 "too many coordinates %d, expected max %d\n",
341 count, ZFORCE_REPORT_POINTS);
342 count = ZFORCE_REPORT_POINTS;
343 }
344
345 for (i = 0; i < count; i++) {
346 point.coord_x =
347 payload[9 * i + 2] << 8 | payload[9 * i + 1];
348 point.coord_y =
349 payload[9 * i + 4] << 8 | payload[9 * i + 3];
350
351 if (point.coord_x > pdata->x_max ||
352 point.coord_y > pdata->y_max) {
353 dev_warn(&client->dev, "coordinates (%d,%d) invalid\n",
354 point.coord_x, point.coord_y);
355 point.coord_x = point.coord_y = 0;
356 }
357
358 point.state = payload[9 * i + 5] & 0x03;
359 point.id = (payload[9 * i + 5] & 0xfc) >> 2;
360
361 /* determine touch major, minor and orientation */
362 point.area_major = max(payload[9 * i + 6],
363 payload[9 * i + 7]);
364 point.area_minor = min(payload[9 * i + 6],
365 payload[9 * i + 7]);
366 point.orientation = payload[9 * i + 6] > payload[9 * i + 7];
367
368 point.pressure = payload[9 * i + 8];
369 point.prblty = payload[9 * i + 9];
370
371 dev_dbg(&client->dev,
372 "point %d/%d: state %d, id %d, pressure %d, prblty %d, x %d, y %d, amajor %d, aminor %d, ori %d\n",
373 i, count, point.state, point.id,
374 point.pressure, point.prblty,
375 point.coord_x, point.coord_y,
376 point.area_major, point.area_minor,
377 point.orientation);
378
379 /* the zforce id starts with "1", so needs to be decreased */
380 input_mt_slot(ts->input, point.id - 1);
381
382 input_mt_report_slot_state(ts->input, MT_TOOL_FINGER,
383 point.state != STATE_UP);
384
385 if (point.state != STATE_UP) {
386 input_report_abs(ts->input, ABS_MT_POSITION_X,
387 point.coord_x);
388 input_report_abs(ts->input, ABS_MT_POSITION_Y,
389 point.coord_y);
390 input_report_abs(ts->input, ABS_MT_TOUCH_MAJOR,
391 point.area_major);
392 input_report_abs(ts->input, ABS_MT_TOUCH_MINOR,
393 point.area_minor);
394 input_report_abs(ts->input, ABS_MT_ORIENTATION,
395 point.orientation);
396 num++;
397 }
398 }
399
400 input_mt_sync_frame(ts->input);
401
402 input_mt_report_finger_count(ts->input, num);
403
404 input_sync(ts->input);
405
406 return 0;
407}
408
409static int zforce_read_packet(struct zforce_ts *ts, u8 *buf)
410{
411 struct i2c_client *client = ts->client;
412 int ret;
413
414 mutex_lock(&ts->access_mutex);
415
416 /* read 2 byte message header */
417 ret = i2c_master_recv(client, buf, 2);
418 if (ret < 0) {
419 dev_err(&client->dev, "error reading header: %d\n", ret);
420 goto unlock;
421 }
422
423 if (buf[PAYLOAD_HEADER] != FRAME_START) {
424 dev_err(&client->dev, "invalid frame start: %d\n", buf[0]);
425 ret = -EIO;
426 goto unlock;
427 }
428
429 if (buf[PAYLOAD_LENGTH] == 0) {
430 dev_err(&client->dev, "invalid payload length: %d\n",
431 buf[PAYLOAD_LENGTH]);
432 ret = -EIO;
433 goto unlock;
434 }
435
436 /* read the message */
437 ret = i2c_master_recv(client, &buf[PAYLOAD_BODY], buf[PAYLOAD_LENGTH]);
438 if (ret < 0) {
439 dev_err(&client->dev, "error reading payload: %d\n", ret);
440 goto unlock;
441 }
442
443 dev_dbg(&client->dev, "read %d bytes for response command 0x%x\n",
444 buf[PAYLOAD_LENGTH], buf[PAYLOAD_BODY]);
445
446unlock:
447 mutex_unlock(&ts->access_mutex);
448 return ret;
449}
450
451static void zforce_complete(struct zforce_ts *ts, int cmd, int result)
452{
453 struct i2c_client *client = ts->client;
454
455 if (ts->command_waiting == cmd) {
456 dev_dbg(&client->dev, "completing command 0x%x\n", cmd);
457 ts->command_result = result;
458 complete(&ts->command_done);
459 } else {
460 dev_dbg(&client->dev, "command %d not for us\n", cmd);
461 }
462}
463
464static irqreturn_t zforce_irq(int irq, void *dev_id)
465{
466 struct zforce_ts *ts = dev_id;
467 struct i2c_client *client = ts->client;
468
469 if (ts->suspended && device_may_wakeup(&client->dev))
470 pm_wakeup_event(&client->dev, 500);
471
472 return IRQ_WAKE_THREAD;
473}
474
475static irqreturn_t zforce_irq_thread(int irq, void *dev_id)
476{
477 struct zforce_ts *ts = dev_id;
478 struct i2c_client *client = ts->client;
479 const struct zforce_ts_platdata *pdata = ts->pdata;
480 int ret;
481 u8 payload_buffer[FRAME_MAXSIZE];
482 u8 *payload;
483
484 /*
485 * When still suspended, return.
486 * Due to the level-interrupt we will get re-triggered later.
487 */
488 if (ts->suspended) {
489 msleep(20);
490 return IRQ_HANDLED;
491 }
492
493 dev_dbg(&client->dev, "handling interrupt\n");
494
495 /* Don't emit wakeup events from commands run by zforce_suspend */
496 if (!ts->suspending && device_may_wakeup(&client->dev))
497 pm_stay_awake(&client->dev);
498
499 while (!gpio_get_value(pdata->gpio_int)) {
500 ret = zforce_read_packet(ts, payload_buffer);
501 if (ret < 0) {
502 dev_err(&client->dev,
503 "could not read packet, ret: %d\n", ret);
504 break;
505 }
506
507 payload = &payload_buffer[PAYLOAD_BODY];
508
509 switch (payload[RESPONSE_ID]) {
510 case NOTIFICATION_TOUCH:
511 /*
512 * Always report touch-events received while
513 * suspending, when being a wakeup source
514 */
515 if (ts->suspending && device_may_wakeup(&client->dev))
516 pm_wakeup_event(&client->dev, 500);
517 zforce_touch_event(ts, &payload[RESPONSE_DATA]);
518 break;
519
520 case NOTIFICATION_BOOTCOMPLETE:
521 ts->boot_complete = payload[RESPONSE_DATA];
522 zforce_complete(ts, payload[RESPONSE_ID], 0);
523 break;
524
525 case RESPONSE_INITIALIZE:
526 case RESPONSE_DEACTIVATE:
527 case RESPONSE_SETCONFIG:
528 case RESPONSE_RESOLUTION:
529 case RESPONSE_SCANFREQ:
530 zforce_complete(ts, payload[RESPONSE_ID],
531 payload[RESPONSE_DATA]);
532 break;
533
534 case RESPONSE_STATUS:
535 /*
536 * Version Payload Results
537 * [2:major] [2:minor] [2:build] [2:rev]
538 */
539 ts->version_major = (payload[RESPONSE_DATA + 1] << 8) |
540 payload[RESPONSE_DATA];
541 ts->version_minor = (payload[RESPONSE_DATA + 3] << 8) |
542 payload[RESPONSE_DATA + 2];
543 ts->version_build = (payload[RESPONSE_DATA + 5] << 8) |
544 payload[RESPONSE_DATA + 4];
545 ts->version_rev = (payload[RESPONSE_DATA + 7] << 8) |
546 payload[RESPONSE_DATA + 6];
547 dev_dbg(&ts->client->dev,
548 "Firmware Version %04x:%04x %04x:%04x\n",
549 ts->version_major, ts->version_minor,
550 ts->version_build, ts->version_rev);
551
552 zforce_complete(ts, payload[RESPONSE_ID], 0);
553 break;
554
555 case NOTIFICATION_INVALID_COMMAND:
556 dev_err(&ts->client->dev, "invalid command: 0x%x\n",
557 payload[RESPONSE_DATA]);
558 break;
559
560 default:
561 dev_err(&ts->client->dev,
562 "unrecognized response id: 0x%x\n",
563 payload[RESPONSE_ID]);
564 break;
565 }
566 }
567
568 if (!ts->suspending && device_may_wakeup(&client->dev))
569 pm_relax(&client->dev);
570
571 dev_dbg(&client->dev, "finished interrupt\n");
572
573 return IRQ_HANDLED;
574}
575
576static int zforce_input_open(struct input_dev *dev)
577{
578 struct zforce_ts *ts = input_get_drvdata(dev);
579 int ret;
580
581 ret = zforce_start(ts);
582 if (ret)
583 return ret;
584
585 return 0;
586}
587
588static void zforce_input_close(struct input_dev *dev)
589{
590 struct zforce_ts *ts = input_get_drvdata(dev);
591 struct i2c_client *client = ts->client;
592 int ret;
593
594 ret = zforce_stop(ts);
595 if (ret)
596 dev_warn(&client->dev, "stopping zforce failed\n");
597
598 return;
599}
600
601#ifdef CONFIG_PM_SLEEP
602static int zforce_suspend(struct device *dev)
603{
604 struct i2c_client *client = to_i2c_client(dev);
605 struct zforce_ts *ts = i2c_get_clientdata(client);
606 struct input_dev *input = ts->input;
607 int ret = 0;
608
609 mutex_lock(&input->mutex);
610 ts->suspending = true;
611
612 /*
613 * When configured as a wakeup source device should always wake
614 * the system, therefore start device if necessary.
615 */
616 if (device_may_wakeup(&client->dev)) {
617 dev_dbg(&client->dev, "suspend while being a wakeup source\n");
618
619 /* Need to start device, if not open, to be a wakeup source. */
620 if (!input->users) {
621 ret = zforce_start(ts);
622 if (ret)
623 goto unlock;
624 }
625
626 enable_irq_wake(client->irq);
627 } else if (input->users) {
628 dev_dbg(&client->dev,
629 "suspend without being a wakeup source\n");
630
631 ret = zforce_stop(ts);
632 if (ret)
633 goto unlock;
634
635 disable_irq(client->irq);
636 }
637
638 ts->suspended = true;
639
640unlock:
641 ts->suspending = false;
642 mutex_unlock(&input->mutex);
643
644 return ret;
645}
646
647static int zforce_resume(struct device *dev)
648{
649 struct i2c_client *client = to_i2c_client(dev);
650 struct zforce_ts *ts = i2c_get_clientdata(client);
651 struct input_dev *input = ts->input;
652 int ret = 0;
653
654 mutex_lock(&input->mutex);
655
656 ts->suspended = false;
657
658 if (device_may_wakeup(&client->dev)) {
659 dev_dbg(&client->dev, "resume from being a wakeup source\n");
660
661 disable_irq_wake(client->irq);
662
663 /* need to stop device if it was not open on suspend */
664 if (!input->users) {
665 ret = zforce_stop(ts);
666 if (ret)
667 goto unlock;
668 }
669 } else if (input->users) {
670 dev_dbg(&client->dev, "resume without being a wakeup source\n");
671
672 enable_irq(client->irq);
673
674 ret = zforce_start(ts);
675 if (ret < 0)
676 goto unlock;
677 }
678
679unlock:
680 mutex_unlock(&input->mutex);
681
682 return ret;
683}
684#endif
685
686static SIMPLE_DEV_PM_OPS(zforce_pm_ops, zforce_suspend, zforce_resume);
687
688static void zforce_reset(void *data)
689{
690 struct zforce_ts *ts = data;
691
692 gpio_set_value(ts->pdata->gpio_rst, 0);
693}
694
695static struct zforce_ts_platdata *zforce_parse_dt(struct device *dev)
696{
697 struct zforce_ts_platdata *pdata;
698 struct device_node *np = dev->of_node;
699
700 if (!np)
701 return ERR_PTR(-ENOENT);
702
703 pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
704 if (!pdata) {
705 dev_err(dev, "failed to allocate platform data\n");
706 return ERR_PTR(-ENOMEM);
707 }
708
709 pdata->gpio_int = of_get_gpio(np, 0);
710 if (!gpio_is_valid(pdata->gpio_int)) {
711 dev_err(dev, "failed to get interrupt gpio\n");
712 return ERR_PTR(-EINVAL);
713 }
714
715 pdata->gpio_rst = of_get_gpio(np, 1);
716 if (!gpio_is_valid(pdata->gpio_rst)) {
717 dev_err(dev, "failed to get reset gpio\n");
718 return ERR_PTR(-EINVAL);
719 }
720
721 if (of_property_read_u32(np, "x-size", &pdata->x_max)) {
722 dev_err(dev, "failed to get x-size property\n");
723 return ERR_PTR(-EINVAL);
724 }
725
726 if (of_property_read_u32(np, "y-size", &pdata->y_max)) {
727 dev_err(dev, "failed to get y-size property\n");
728 return ERR_PTR(-EINVAL);
729 }
730
731 return pdata;
732}
733
734static int zforce_probe(struct i2c_client *client,
735 const struct i2c_device_id *id)
736{
737 const struct zforce_ts_platdata *pdata = dev_get_platdata(&client->dev);
738 struct zforce_ts *ts;
739 struct input_dev *input_dev;
740 int ret;
741
742 if (!pdata) {
743 pdata = zforce_parse_dt(&client->dev);
744 if (IS_ERR(pdata))
745 return PTR_ERR(pdata);
746 }
747
748 ts = devm_kzalloc(&client->dev, sizeof(struct zforce_ts), GFP_KERNEL);
749 if (!ts)
750 return -ENOMEM;
751
752 ret = devm_gpio_request_one(&client->dev, pdata->gpio_int, GPIOF_IN,
753 "zforce_ts_int");
754 if (ret) {
755 dev_err(&client->dev, "request of gpio %d failed, %d\n",
756 pdata->gpio_int, ret);
757 return ret;
758 }
759
760 ret = devm_gpio_request_one(&client->dev, pdata->gpio_rst,
761 GPIOF_OUT_INIT_LOW, "zforce_ts_rst");
762 if (ret) {
763 dev_err(&client->dev, "request of gpio %d failed, %d\n",
764 pdata->gpio_rst, ret);
765 return ret;
766 }
767
768 ret = devm_add_action(&client->dev, zforce_reset, ts);
769 if (ret) {
770 dev_err(&client->dev, "failed to register reset action, %d\n",
771 ret);
772 return ret;
773 }
774
775 snprintf(ts->phys, sizeof(ts->phys),
776 "%s/input0", dev_name(&client->dev));
777
778 input_dev = devm_input_allocate_device(&client->dev);
779 if (!input_dev) {
780 dev_err(&client->dev, "could not allocate input device\n");
781 return -ENOMEM;
782 }
783
784 mutex_init(&ts->access_mutex);
785 mutex_init(&ts->command_mutex);
786
787 ts->pdata = pdata;
788 ts->client = client;
789 ts->input = input_dev;
790
791 input_dev->name = "Neonode zForce touchscreen";
792 input_dev->phys = ts->phys;
793 input_dev->id.bustype = BUS_I2C;
794
795 input_dev->open = zforce_input_open;
796 input_dev->close = zforce_input_close;
797
798 __set_bit(EV_KEY, input_dev->evbit);
799 __set_bit(EV_SYN, input_dev->evbit);
800 __set_bit(EV_ABS, input_dev->evbit);
801
802 /* For multi touch */
803 input_set_abs_params(input_dev, ABS_MT_POSITION_X, 0,
804 pdata->x_max, 0, 0);
805 input_set_abs_params(input_dev, ABS_MT_POSITION_Y, 0,
806 pdata->y_max, 0, 0);
807
808 input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR, 0,
809 ZFORCE_MAX_AREA, 0, 0);
810 input_set_abs_params(input_dev, ABS_MT_TOUCH_MINOR, 0,
811 ZFORCE_MAX_AREA, 0, 0);
812 input_set_abs_params(input_dev, ABS_MT_ORIENTATION, 0, 1, 0, 0);
813 input_mt_init_slots(input_dev, ZFORCE_REPORT_POINTS, INPUT_MT_DIRECT);
814
815 input_set_drvdata(ts->input, ts);
816
817 init_completion(&ts->command_done);
818
819 /*
820 * The zforce pulls the interrupt low when it has data ready.
821 * After it is triggered the isr thread runs until all the available
822 * packets have been read and the interrupt is high again.
823 * Therefore we can trigger the interrupt anytime it is low and do
824 * not need to limit it to the interrupt edge.
825 */
826 ret = devm_request_threaded_irq(&client->dev, client->irq,
827 zforce_irq, zforce_irq_thread,
828 IRQF_TRIGGER_LOW | IRQF_ONESHOT,
829 input_dev->name, ts);
830 if (ret) {
831 dev_err(&client->dev, "irq %d request failed\n", client->irq);
832 return ret;
833 }
834
835 i2c_set_clientdata(client, ts);
836
837 /* let the controller boot */
838 gpio_set_value(pdata->gpio_rst, 1);
839
840 ts->command_waiting = NOTIFICATION_BOOTCOMPLETE;
841 if (wait_for_completion_timeout(&ts->command_done, WAIT_TIMEOUT) == 0)
842 dev_warn(&client->dev, "bootcomplete timed out\n");
843
844 /* need to start device to get version information */
845 ret = zforce_command_wait(ts, COMMAND_INITIALIZE);
846 if (ret) {
847 dev_err(&client->dev, "unable to initialize, %d\n", ret);
848 return ret;
849 }
850
851 /* this gets the firmware version among other information */
852 ret = zforce_command_wait(ts, COMMAND_STATUS);
853 if (ret < 0) {
854 dev_err(&client->dev, "couldn't get status, %d\n", ret);
855 zforce_stop(ts);
856 return ret;
857 }
858
859 /* stop device and put it into sleep until it is opened */
860 ret = zforce_stop(ts);
861 if (ret < 0)
862 return ret;
863
864 device_set_wakeup_capable(&client->dev, true);
865
866 ret = input_register_device(input_dev);
867 if (ret) {
868 dev_err(&client->dev, "could not register input device, %d\n",
869 ret);
870 return ret;
871 }
872
873 return 0;
874}
875
876static struct i2c_device_id zforce_idtable[] = {
877 { "zforce-ts", 0 },
878 { }
879};
880MODULE_DEVICE_TABLE(i2c, zforce_idtable);
881
882#ifdef CONFIG_OF
883static struct of_device_id zforce_dt_idtable[] = {
884 { .compatible = "neonode,zforce" },
885 {},
886};
887MODULE_DEVICE_TABLE(of, zforce_dt_idtable);
888#endif
889
890static struct i2c_driver zforce_driver = {
891 .driver = {
892 .owner = THIS_MODULE,
893 .name = "zforce-ts",
894 .pm = &zforce_pm_ops,
895 .of_match_table = of_match_ptr(zforce_dt_idtable),
896 },
897 .probe = zforce_probe,
898 .id_table = zforce_idtable,
899};
900
901module_i2c_driver(zforce_driver);
902
903MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>");
904MODULE_DESCRIPTION("zForce TouchScreen Driver");
905MODULE_LICENSE("GPL");
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2012-2013 MundoReader S.L.
4 * Author: Heiko Stuebner <heiko@sntech.de>
5 *
6 * based in parts on Nook zforce driver
7 *
8 * Copyright (C) 2010 Barnes & Noble, Inc.
9 * Author: Pieter Truter<ptruter@intrinsyc.com>
10 */
11
12#include <linux/delay.h>
13#include <linux/device.h>
14#include <linux/gpio/consumer.h>
15#include <linux/i2c.h>
16#include <linux/input.h>
17#include <linux/input/mt.h>
18#include <linux/input/touchscreen.h>
19#include <linux/interrupt.h>
20#include <linux/module.h>
21#include <linux/of.h>
22#include <linux/property.h>
23#include <linux/regulator/consumer.h>
24#include <linux/slab.h>
25#include <linux/unaligned.h>
26
27#define WAIT_TIMEOUT msecs_to_jiffies(1000)
28
29#define FRAME_START 0xee
30#define FRAME_MAXSIZE 257
31
32/* Offsets of the different parts of the payload the controller sends */
33#define PAYLOAD_HEADER 0
34#define PAYLOAD_LENGTH 1
35#define PAYLOAD_BODY 2
36
37/* Response offsets */
38#define RESPONSE_ID 0
39#define RESPONSE_DATA 1
40
41/* Commands */
42#define COMMAND_DEACTIVATE 0x00
43#define COMMAND_INITIALIZE 0x01
44#define COMMAND_RESOLUTION 0x02
45#define COMMAND_SETCONFIG 0x03
46#define COMMAND_DATAREQUEST 0x04
47#define COMMAND_SCANFREQ 0x08
48#define COMMAND_STATUS 0X1e
49
50/*
51 * Responses the controller sends as a result of
52 * command requests
53 */
54#define RESPONSE_DEACTIVATE 0x00
55#define RESPONSE_INITIALIZE 0x01
56#define RESPONSE_RESOLUTION 0x02
57#define RESPONSE_SETCONFIG 0x03
58#define RESPONSE_SCANFREQ 0x08
59#define RESPONSE_STATUS 0X1e
60
61/*
62 * Notifications are sent by the touch controller without
63 * being requested by the driver and include for example
64 * touch indications
65 */
66#define NOTIFICATION_TOUCH 0x04
67#define NOTIFICATION_BOOTCOMPLETE 0x07
68#define NOTIFICATION_OVERRUN 0x25
69#define NOTIFICATION_PROXIMITY 0x26
70#define NOTIFICATION_INVALID_COMMAND 0xfe
71
72#define ZFORCE_REPORT_POINTS 2
73#define ZFORCE_MAX_AREA 0xff
74
75#define STATE_DOWN 0
76#define STATE_MOVE 1
77#define STATE_UP 2
78
79#define SETCONFIG_DUALTOUCH (1 << 0)
80
81struct zforce_point {
82 int coord_x;
83 int coord_y;
84 int state;
85 int id;
86 int area_major;
87 int area_minor;
88 int orientation;
89 int pressure;
90 int prblty;
91};
92
93/*
94 * @client the i2c_client
95 * @input the input device
96 * @suspending in the process of going to suspend (don't emit wakeup
97 * events for commands executed to suspend the device)
98 * @suspended device suspended
99 * @command_done completion to wait for the command result
100 * @command_waiting the id of the command that is currently waiting
101 * for a result
102 * @command_result returned result of the command
103 */
104struct zforce_ts {
105 struct i2c_client *client;
106 struct input_dev *input;
107 struct touchscreen_properties prop;
108 char phys[32];
109
110 struct gpio_desc *gpio_int;
111 struct gpio_desc *gpio_rst;
112
113 bool suspending;
114 bool suspended;
115 bool boot_complete;
116
117 /* Firmware version information */
118 u16 version_major;
119 u16 version_minor;
120 u16 version_build;
121 u16 version_rev;
122
123 struct completion command_done;
124 int command_waiting;
125 int command_result;
126};
127
128static int zforce_command(struct zforce_ts *ts, u8 cmd)
129{
130 struct i2c_client *client = ts->client;
131 char buf[3];
132 int ret;
133
134 dev_dbg(&client->dev, "%s: 0x%x\n", __func__, cmd);
135
136 buf[0] = FRAME_START;
137 buf[1] = 1; /* data size, command only */
138 buf[2] = cmd;
139
140 ret = i2c_master_send(client, &buf[0], ARRAY_SIZE(buf));
141 if (ret < 0) {
142 dev_err(&client->dev, "i2c send data request error: %d\n", ret);
143 return ret;
144 }
145
146 return 0;
147}
148
149static int zforce_send_wait(struct zforce_ts *ts, const char *buf, int len)
150{
151 struct i2c_client *client = ts->client;
152 int ret;
153
154 dev_dbg(&client->dev, "sending %d bytes for command 0x%x\n",
155 buf[1], buf[2]);
156
157 ts->command_waiting = buf[2];
158
159 ret = i2c_master_send(client, buf, len);
160 if (ret < 0) {
161 dev_err(&client->dev, "i2c send data request error: %d\n", ret);
162 return ret;
163 }
164
165 dev_dbg(&client->dev, "waiting for result for command 0x%x\n", buf[2]);
166
167 if (wait_for_completion_timeout(&ts->command_done, WAIT_TIMEOUT) == 0)
168 return -ETIME;
169
170 ret = ts->command_result;
171 return 0;
172}
173
174static int zforce_command_wait(struct zforce_ts *ts, u8 cmd)
175{
176 struct i2c_client *client = ts->client;
177 char buf[3];
178 int error;
179
180 dev_dbg(&client->dev, "%s: 0x%x\n", __func__, cmd);
181
182 buf[0] = FRAME_START;
183 buf[1] = 1; /* data size, command only */
184 buf[2] = cmd;
185
186 error = zforce_send_wait(ts, &buf[0], ARRAY_SIZE(buf));
187 if (error) {
188 dev_err(&client->dev, "i2c send data request error: %d\n",
189 error);
190 return error;
191 }
192
193 return 0;
194}
195
196static int zforce_resolution(struct zforce_ts *ts, u16 x, u16 y)
197{
198 struct i2c_client *client = ts->client;
199 char buf[7] = { FRAME_START, 5, COMMAND_RESOLUTION,
200 (x & 0xff), ((x >> 8) & 0xff),
201 (y & 0xff), ((y >> 8) & 0xff) };
202
203 dev_dbg(&client->dev, "set resolution to (%d,%d)\n", x, y);
204
205 return zforce_send_wait(ts, &buf[0], ARRAY_SIZE(buf));
206}
207
208static int zforce_scan_frequency(struct zforce_ts *ts, u16 idle, u16 finger,
209 u16 stylus)
210{
211 struct i2c_client *client = ts->client;
212 char buf[9] = { FRAME_START, 7, COMMAND_SCANFREQ,
213 (idle & 0xff), ((idle >> 8) & 0xff),
214 (finger & 0xff), ((finger >> 8) & 0xff),
215 (stylus & 0xff), ((stylus >> 8) & 0xff) };
216
217 dev_dbg(&client->dev,
218 "set scan frequency to (idle: %d, finger: %d, stylus: %d)\n",
219 idle, finger, stylus);
220
221 return zforce_send_wait(ts, &buf[0], ARRAY_SIZE(buf));
222}
223
224static int zforce_setconfig(struct zforce_ts *ts, char b1)
225{
226 struct i2c_client *client = ts->client;
227 char buf[7] = { FRAME_START, 5, COMMAND_SETCONFIG,
228 b1, 0, 0, 0 };
229
230 dev_dbg(&client->dev, "set config to (%d)\n", b1);
231
232 return zforce_send_wait(ts, &buf[0], ARRAY_SIZE(buf));
233}
234
235static int zforce_start(struct zforce_ts *ts)
236{
237 struct i2c_client *client = ts->client;
238 int error;
239
240 dev_dbg(&client->dev, "starting device\n");
241
242 error = zforce_command_wait(ts, COMMAND_INITIALIZE);
243 if (error) {
244 dev_err(&client->dev, "Unable to initialize, %d\n", error);
245 return error;
246 }
247
248 error = zforce_resolution(ts, ts->prop.max_x, ts->prop.max_y);
249 if (error) {
250 dev_err(&client->dev, "Unable to set resolution, %d\n", error);
251 goto err_deactivate;
252 }
253
254 error = zforce_scan_frequency(ts, 10, 50, 50);
255 if (error) {
256 dev_err(&client->dev, "Unable to set scan frequency, %d\n",
257 error);
258 goto err_deactivate;
259 }
260
261 error = zforce_setconfig(ts, SETCONFIG_DUALTOUCH);
262 if (error) {
263 dev_err(&client->dev, "Unable to set config\n");
264 goto err_deactivate;
265 }
266
267 /* start sending touch events */
268 error = zforce_command(ts, COMMAND_DATAREQUEST);
269 if (error) {
270 dev_err(&client->dev, "Unable to request data\n");
271 goto err_deactivate;
272 }
273
274 /*
275 * Per NN, initial cal. take max. of 200msec.
276 * Allow time to complete this calibration
277 */
278 msleep(200);
279
280 return 0;
281
282err_deactivate:
283 zforce_command_wait(ts, COMMAND_DEACTIVATE);
284 return error;
285}
286
287static int zforce_stop(struct zforce_ts *ts)
288{
289 struct i2c_client *client = ts->client;
290 int error;
291
292 dev_dbg(&client->dev, "stopping device\n");
293
294 /* Deactivates touch sensing and puts the device into sleep. */
295 error = zforce_command_wait(ts, COMMAND_DEACTIVATE);
296 if (error) {
297 dev_err(&client->dev, "could not deactivate device, %d\n",
298 error);
299 return error;
300 }
301
302 return 0;
303}
304
305static int zforce_touch_event(struct zforce_ts *ts, u8 *payload)
306{
307 struct i2c_client *client = ts->client;
308 struct zforce_point point;
309 int count, i, num = 0;
310 u8 *p;
311
312 count = payload[0];
313 if (count > ZFORCE_REPORT_POINTS) {
314 dev_warn(&client->dev,
315 "too many coordinates %d, expected max %d\n",
316 count, ZFORCE_REPORT_POINTS);
317 count = ZFORCE_REPORT_POINTS;
318 }
319
320 for (i = 0; i < count; i++) {
321 p = &payload[i * 9 + 1];
322
323 point.coord_x = get_unaligned_le16(&p[0]);
324 point.coord_y = get_unaligned_le16(&p[2]);
325
326 if (point.coord_x > ts->prop.max_x ||
327 point.coord_y > ts->prop.max_y) {
328 dev_warn(&client->dev, "coordinates (%d,%d) invalid\n",
329 point.coord_x, point.coord_y);
330 point.coord_x = point.coord_y = 0;
331 }
332
333 point.state = p[4] & 0x0f;
334 point.id = (p[4] & 0xf0) >> 4;
335
336 /* determine touch major, minor and orientation */
337 point.area_major = max(p[5], p[6]);
338 point.area_minor = min(p[5], p[6]);
339 point.orientation = p[5] > p[6];
340
341 point.pressure = p[7];
342 point.prblty = p[8];
343
344 dev_dbg(&client->dev,
345 "point %d/%d: state %d, id %d, pressure %d, prblty %d, x %d, y %d, amajor %d, aminor %d, ori %d\n",
346 i, count, point.state, point.id,
347 point.pressure, point.prblty,
348 point.coord_x, point.coord_y,
349 point.area_major, point.area_minor,
350 point.orientation);
351
352 /* the zforce id starts with "1", so needs to be decreased */
353 input_mt_slot(ts->input, point.id - 1);
354
355 if (input_mt_report_slot_state(ts->input, MT_TOOL_FINGER,
356 point.state != STATE_UP)) {
357 touchscreen_report_pos(ts->input, &ts->prop,
358 point.coord_x, point.coord_y,
359 true);
360 input_report_abs(ts->input, ABS_MT_TOUCH_MAJOR,
361 point.area_major);
362 input_report_abs(ts->input, ABS_MT_TOUCH_MINOR,
363 point.area_minor);
364 input_report_abs(ts->input, ABS_MT_ORIENTATION,
365 point.orientation);
366 num++;
367 }
368 }
369
370 input_mt_sync_frame(ts->input);
371
372 input_mt_report_finger_count(ts->input, num);
373
374 input_sync(ts->input);
375
376 return 0;
377}
378
379static int zforce_read_packet(struct zforce_ts *ts, u8 *buf)
380{
381 struct i2c_client *client = ts->client;
382 int ret;
383
384 /* read 2 byte message header */
385 ret = i2c_master_recv(client, buf, 2);
386 if (ret < 0) {
387 dev_err(&client->dev, "error reading header: %d\n", ret);
388 return ret;
389 }
390
391 if (buf[PAYLOAD_HEADER] != FRAME_START) {
392 dev_err(&client->dev, "invalid frame start: %d\n", buf[0]);
393 return -EIO;
394 }
395
396 if (buf[PAYLOAD_LENGTH] == 0) {
397 dev_err(&client->dev, "invalid payload length: %d\n",
398 buf[PAYLOAD_LENGTH]);
399 return -EIO;
400 }
401
402 /* read the message */
403 ret = i2c_master_recv(client, &buf[PAYLOAD_BODY], buf[PAYLOAD_LENGTH]);
404 if (ret < 0) {
405 dev_err(&client->dev, "error reading payload: %d\n", ret);
406 return ret;
407 }
408
409 dev_dbg(&client->dev, "read %d bytes for response command 0x%x\n",
410 buf[PAYLOAD_LENGTH], buf[PAYLOAD_BODY]);
411
412 return 0;
413}
414
415static void zforce_complete(struct zforce_ts *ts, int cmd, int result)
416{
417 struct i2c_client *client = ts->client;
418
419 if (ts->command_waiting == cmd) {
420 dev_dbg(&client->dev, "completing command 0x%x\n", cmd);
421 ts->command_result = result;
422 complete(&ts->command_done);
423 } else {
424 dev_dbg(&client->dev, "command %d not for us\n", cmd);
425 }
426}
427
428static irqreturn_t zforce_irq(int irq, void *dev_id)
429{
430 struct zforce_ts *ts = dev_id;
431 struct i2c_client *client = ts->client;
432
433 if (ts->suspended && device_may_wakeup(&client->dev))
434 pm_wakeup_event(&client->dev, 500);
435
436 return IRQ_WAKE_THREAD;
437}
438
439static irqreturn_t zforce_irq_thread(int irq, void *dev_id)
440{
441 struct zforce_ts *ts = dev_id;
442 struct i2c_client *client = ts->client;
443 int error;
444 u8 payload_buffer[FRAME_MAXSIZE];
445 u8 *payload;
446 bool suspending;
447
448 /*
449 * When still suspended, return.
450 * Due to the level-interrupt we will get re-triggered later.
451 */
452 if (ts->suspended) {
453 msleep(20);
454 return IRQ_HANDLED;
455 }
456
457 dev_dbg(&client->dev, "handling interrupt\n");
458
459 /* Don't emit wakeup events from commands run by zforce_suspend */
460 suspending = READ_ONCE(ts->suspending);
461 if (!suspending && device_may_wakeup(&client->dev))
462 pm_stay_awake(&client->dev);
463
464 /*
465 * Run at least once and exit the loop if
466 * - the optional interrupt GPIO isn't specified
467 * (there is only one packet read per ISR invocation, then)
468 * or
469 * - the GPIO isn't active any more
470 * (packet read until the level GPIO indicates that there is
471 * no IRQ any more)
472 */
473 do {
474 error = zforce_read_packet(ts, payload_buffer);
475 if (error) {
476 dev_err(&client->dev,
477 "could not read packet, ret: %d\n", error);
478 break;
479 }
480
481 payload = &payload_buffer[PAYLOAD_BODY];
482
483 switch (payload[RESPONSE_ID]) {
484 case NOTIFICATION_TOUCH:
485 /*
486 * Always report touch-events received while
487 * suspending, when being a wakeup source
488 */
489 if (suspending && device_may_wakeup(&client->dev))
490 pm_wakeup_event(&client->dev, 500);
491 zforce_touch_event(ts, &payload[RESPONSE_DATA]);
492 break;
493
494 case NOTIFICATION_BOOTCOMPLETE:
495 ts->boot_complete = payload[RESPONSE_DATA];
496 zforce_complete(ts, payload[RESPONSE_ID], 0);
497 break;
498
499 case RESPONSE_INITIALIZE:
500 case RESPONSE_DEACTIVATE:
501 case RESPONSE_SETCONFIG:
502 case RESPONSE_RESOLUTION:
503 case RESPONSE_SCANFREQ:
504 zforce_complete(ts, payload[RESPONSE_ID],
505 payload[RESPONSE_DATA]);
506 break;
507
508 case RESPONSE_STATUS:
509 /*
510 * Version Payload Results
511 * [2:major] [2:minor] [2:build] [2:rev]
512 */
513 ts->version_major =
514 get_unaligned_le16(&payload[RESPONSE_DATA]);
515 ts->version_minor =
516 get_unaligned_le16(&payload[RESPONSE_DATA + 2]);
517 ts->version_build =
518 get_unaligned_le16(&payload[RESPONSE_DATA + 4]);
519 ts->version_rev =
520 get_unaligned_le16(&payload[RESPONSE_DATA + 6]);
521
522 dev_dbg(&ts->client->dev,
523 "Firmware Version %04x:%04x %04x:%04x\n",
524 ts->version_major, ts->version_minor,
525 ts->version_build, ts->version_rev);
526
527 zforce_complete(ts, payload[RESPONSE_ID], 0);
528 break;
529
530 case NOTIFICATION_INVALID_COMMAND:
531 dev_err(&ts->client->dev, "invalid command: 0x%x\n",
532 payload[RESPONSE_DATA]);
533 break;
534
535 default:
536 dev_err(&ts->client->dev,
537 "unrecognized response id: 0x%x\n",
538 payload[RESPONSE_ID]);
539 break;
540 }
541 } while (gpiod_get_value_cansleep(ts->gpio_int));
542
543 if (!suspending && device_may_wakeup(&client->dev))
544 pm_relax(&client->dev);
545
546 dev_dbg(&client->dev, "finished interrupt\n");
547
548 return IRQ_HANDLED;
549}
550
551static int zforce_input_open(struct input_dev *dev)
552{
553 struct zforce_ts *ts = input_get_drvdata(dev);
554
555 return zforce_start(ts);
556}
557
558static void zforce_input_close(struct input_dev *dev)
559{
560 struct zforce_ts *ts = input_get_drvdata(dev);
561 struct i2c_client *client = ts->client;
562 int error;
563
564 error = zforce_stop(ts);
565 if (error)
566 dev_warn(&client->dev, "stopping zforce failed\n");
567}
568
569static int __zforce_suspend(struct zforce_ts *ts)
570{
571 struct i2c_client *client = ts->client;
572 struct input_dev *input = ts->input;
573 int error;
574
575 guard(mutex)(&input->mutex);
576
577 /*
578 * When configured as a wakeup source device should always wake
579 * the system, therefore start device if necessary.
580 */
581 if (device_may_wakeup(&client->dev)) {
582 dev_dbg(&client->dev, "suspend while being a wakeup source\n");
583
584 /* Need to start device, if not open, to be a wakeup source. */
585 if (!input_device_enabled(input)) {
586 error = zforce_start(ts);
587 if (error)
588 return error;
589 }
590
591 enable_irq_wake(client->irq);
592 } else if (input_device_enabled(input)) {
593 dev_dbg(&client->dev,
594 "suspend without being a wakeup source\n");
595
596 error = zforce_stop(ts);
597 if (error)
598 return error;
599
600 disable_irq(client->irq);
601 }
602
603 ts->suspended = true;
604 return 0;
605}
606
607static int zforce_suspend(struct device *dev)
608{
609 struct i2c_client *client = to_i2c_client(dev);
610 struct zforce_ts *ts = i2c_get_clientdata(client);
611 int ret;
612
613 WRITE_ONCE(ts->suspending, true);
614 smp_mb();
615
616 ret = __zforce_suspend(ts);
617
618 smp_mb();
619 WRITE_ONCE(ts->suspending, false);
620
621 return ret;
622}
623
624static int zforce_resume(struct device *dev)
625{
626 struct i2c_client *client = to_i2c_client(dev);
627 struct zforce_ts *ts = i2c_get_clientdata(client);
628 struct input_dev *input = ts->input;
629 int error;
630
631 guard(mutex)(&input->mutex);
632
633 ts->suspended = false;
634
635 if (device_may_wakeup(&client->dev)) {
636 dev_dbg(&client->dev, "resume from being a wakeup source\n");
637
638 disable_irq_wake(client->irq);
639
640 /* need to stop device if it was not open on suspend */
641 if (!input_device_enabled(input)) {
642 error = zforce_stop(ts);
643 if (error)
644 return error;
645 }
646 } else if (input_device_enabled(input)) {
647 dev_dbg(&client->dev, "resume without being a wakeup source\n");
648
649 enable_irq(client->irq);
650
651 error = zforce_start(ts);
652 if (error)
653 return error;
654 }
655
656 return 0;
657}
658
659static DEFINE_SIMPLE_DEV_PM_OPS(zforce_pm_ops, zforce_suspend, zforce_resume);
660
661static void zforce_reset(void *data)
662{
663 struct zforce_ts *ts = data;
664
665 gpiod_set_value_cansleep(ts->gpio_rst, 1);
666 udelay(10);
667}
668
669static void zforce_ts_parse_legacy_properties(struct zforce_ts *ts)
670{
671 u32 x_max = 0;
672 u32 y_max = 0;
673
674 device_property_read_u32(&ts->client->dev, "x-size", &x_max);
675 input_set_abs_params(ts->input, ABS_MT_POSITION_X, 0, x_max, 0, 0);
676
677 device_property_read_u32(&ts->client->dev, "y-size", &y_max);
678 input_set_abs_params(ts->input, ABS_MT_POSITION_Y, 0, y_max, 0, 0);
679}
680
681static int zforce_probe(struct i2c_client *client)
682{
683 struct zforce_ts *ts;
684 struct input_dev *input_dev;
685 int error;
686
687 ts = devm_kzalloc(&client->dev, sizeof(struct zforce_ts), GFP_KERNEL);
688 if (!ts)
689 return -ENOMEM;
690
691 ts->gpio_rst = devm_gpiod_get_optional(&client->dev, "reset",
692 GPIOD_OUT_HIGH);
693 error = PTR_ERR_OR_ZERO(ts->gpio_rst);
694 if (error)
695 return dev_err_probe(&client->dev, error,
696 "failed to request reset GPIO\n");
697
698 if (ts->gpio_rst) {
699 ts->gpio_int = devm_gpiod_get_optional(&client->dev, "irq",
700 GPIOD_IN);
701 error = PTR_ERR_OR_ZERO(ts->gpio_int);
702 if (error)
703 return dev_err_probe(&client->dev, error,
704 "failed to request interrupt GPIO\n");
705 } else {
706 /*
707 * Deprecated GPIO handling for compatibility
708 * with legacy binding.
709 */
710
711 /* INT GPIO */
712 ts->gpio_int = devm_gpiod_get_index(&client->dev, NULL, 0,
713 GPIOD_IN);
714
715 error = PTR_ERR_OR_ZERO(ts->gpio_int);
716 if (error)
717 return dev_err_probe(&client->dev, error,
718 "failed to request interrupt GPIO\n");
719
720 /* RST GPIO */
721 ts->gpio_rst = devm_gpiod_get_index(&client->dev, NULL, 1,
722 GPIOD_OUT_HIGH);
723 error = PTR_ERR_OR_ZERO(ts->gpio_rst);
724 if (error)
725 return dev_err_probe(&client->dev, error,
726 "failed to request reset GPIO\n");
727 }
728
729 error = devm_regulator_get_enable(&client->dev, "vdd");
730 if (error)
731 return dev_err_probe(&client->dev, error,
732 "failed to request vdd supply\n");
733
734 /*
735 * According to datasheet add 100us grace time after regular
736 * regulator enable delay.
737 */
738 usleep_range(100, 200);
739
740 error = devm_add_action_or_reset(&client->dev, zforce_reset, ts);
741 if (error)
742 return dev_err_probe(&client->dev, error,
743 "failed to register reset action\n");
744
745 snprintf(ts->phys, sizeof(ts->phys),
746 "%s/input0", dev_name(&client->dev));
747
748 input_dev = devm_input_allocate_device(&client->dev);
749 if (!input_dev)
750 return dev_err_probe(&client->dev, -ENOMEM,
751 "could not allocate input device\n");
752
753 ts->client = client;
754 ts->input = input_dev;
755
756 input_dev->name = "Neonode zForce touchscreen";
757 input_dev->phys = ts->phys;
758 input_dev->id.bustype = BUS_I2C;
759
760 input_dev->open = zforce_input_open;
761 input_dev->close = zforce_input_close;
762
763 zforce_ts_parse_legacy_properties(ts);
764 touchscreen_parse_properties(input_dev, true, &ts->prop);
765 if (ts->prop.max_x == 0 || ts->prop.max_y == 0)
766 return dev_err_probe(&client->dev, -EINVAL, "no size specified");
767
768 input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR, 0,
769 ZFORCE_MAX_AREA, 0, 0);
770 input_set_abs_params(input_dev, ABS_MT_TOUCH_MINOR, 0,
771 ZFORCE_MAX_AREA, 0, 0);
772 input_set_abs_params(input_dev, ABS_MT_ORIENTATION, 0, 1, 0, 0);
773
774 error = input_mt_init_slots(input_dev, ZFORCE_REPORT_POINTS,
775 INPUT_MT_DIRECT);
776 if (error)
777 return error;
778
779 input_set_drvdata(ts->input, ts);
780
781 init_completion(&ts->command_done);
782
783 /*
784 * The zforce pulls the interrupt low when it has data ready.
785 * After it is triggered the isr thread runs until all the available
786 * packets have been read and the interrupt is high again.
787 * Therefore we can trigger the interrupt anytime it is low and do
788 * not need to limit it to the interrupt edge.
789 */
790 error = devm_request_threaded_irq(&client->dev, client->irq,
791 zforce_irq, zforce_irq_thread,
792 IRQF_ONESHOT, input_dev->name, ts);
793 if (error)
794 return dev_err_probe(&client->dev, error,
795 "irq %d request failed\n", client->irq);
796
797 i2c_set_clientdata(client, ts);
798
799 /* let the controller boot */
800 gpiod_set_value_cansleep(ts->gpio_rst, 0);
801
802 ts->command_waiting = NOTIFICATION_BOOTCOMPLETE;
803 if (wait_for_completion_timeout(&ts->command_done, WAIT_TIMEOUT) == 0)
804 dev_warn(&client->dev, "bootcomplete timed out\n");
805
806 /* need to start device to get version information */
807 error = zforce_command_wait(ts, COMMAND_INITIALIZE);
808 if (error)
809 return dev_err_probe(&client->dev, error, "unable to initialize\n");
810
811 /* this gets the firmware version among other information */
812 error = zforce_command_wait(ts, COMMAND_STATUS);
813 if (error) {
814 dev_err_probe(&client->dev, error, "couldn't get status\n");
815 zforce_stop(ts);
816 return error;
817 }
818
819 /* stop device and put it into sleep until it is opened */
820 error = zforce_stop(ts);
821 if (error)
822 return error;
823
824 device_set_wakeup_capable(&client->dev, true);
825
826 error = input_register_device(input_dev);
827 if (error)
828 return dev_err_probe(&client->dev, error,
829 "could not register input device\n");
830
831 return 0;
832}
833
834static const struct i2c_device_id zforce_idtable[] = {
835 { "zforce-ts" },
836 { }
837};
838MODULE_DEVICE_TABLE(i2c, zforce_idtable);
839
840#ifdef CONFIG_OF
841static const struct of_device_id zforce_dt_idtable[] = {
842 { .compatible = "neonode,zforce" },
843 {},
844};
845MODULE_DEVICE_TABLE(of, zforce_dt_idtable);
846#endif
847
848static struct i2c_driver zforce_driver = {
849 .driver = {
850 .name = "zforce-ts",
851 .pm = pm_sleep_ptr(&zforce_pm_ops),
852 .of_match_table = of_match_ptr(zforce_dt_idtable),
853 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
854 },
855 .probe = zforce_probe,
856 .id_table = zforce_idtable,
857};
858
859module_i2c_driver(zforce_driver);
860
861MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>");
862MODULE_DESCRIPTION("zForce TouchScreen Driver");
863MODULE_LICENSE("GPL");