2 * Copyright (C) 2012-2013 MundoReader S.L.
3 * Author: Heiko Stuebner <heiko@sntech.de>
5 * based in parts on Nook zforce driver
7 * Copyright (C) 2010 Barnes & Noble, Inc.
8 * Author: Pieter Truter<ptruter@intrinsyc.com>
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.
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.
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>
33 #define WAIT_TIMEOUT msecs_to_jiffies(1000)
35 #define FRAME_START 0xee
37 /* Offsets of the different parts of the payload the controller sends */
38 #define PAYLOAD_HEADER 0
39 #define PAYLOAD_LENGTH 1
40 #define PAYLOAD_BODY 2
42 /* Response offsets */
44 #define RESPONSE_DATA 1
47 #define COMMAND_DEACTIVATE 0x00
48 #define COMMAND_INITIALIZE 0x01
49 #define COMMAND_RESOLUTION 0x02
50 #define COMMAND_SETCONFIG 0x03
51 #define COMMAND_DATAREQUEST 0x04
52 #define COMMAND_SCANFREQ 0x08
53 #define COMMAND_STATUS 0X1e
56 * Responses the controller sends as a result of
59 #define RESPONSE_DEACTIVATE 0x00
60 #define RESPONSE_INITIALIZE 0x01
61 #define RESPONSE_RESOLUTION 0x02
62 #define RESPONSE_SETCONFIG 0x03
63 #define RESPONSE_SCANFREQ 0x08
64 #define RESPONSE_STATUS 0X1e
67 * Notifications are send by the touch controller without
68 * being requested by the driver and include for example
71 #define NOTIFICATION_TOUCH 0x04
72 #define NOTIFICATION_BOOTCOMPLETE 0x07
73 #define NOTIFICATION_OVERRUN 0x25
74 #define NOTIFICATION_PROXIMITY 0x26
75 #define NOTIFICATION_INVALID_COMMAND 0xfe
77 #define ZFORCE_REPORT_POINTS 2
78 #define ZFORCE_MAX_AREA 0xff
84 #define SETCONFIG_DUALTOUCH (1 << 0)
99 * @client the i2c_client
100 * @input the input device
101 * @suspending in the process of going to suspend (don't emit wakeup
102 * events for commands executed to suspend the device)
103 * @suspended device suspended
104 * @access_mutex serialize i2c-access, to keep multipart reads together
105 * @command_done completion to wait for the command result
106 * @command_mutex serialize commands send to the ic
107 * @command_waiting the id of the command that that is currently waiting
109 * @command_result returned result of the command
112 struct i2c_client *client;
113 struct input_dev *input;
114 const struct zforce_ts_platdata *pdata;
121 /* Firmware version information */
127 struct mutex access_mutex;
129 struct completion command_done;
130 struct mutex command_mutex;
135 static int zforce_command(struct zforce_ts *ts, u8 cmd)
137 struct i2c_client *client = ts->client;
141 dev_dbg(&client->dev, "%s: 0x%x\n", __func__, cmd);
143 buf[0] = FRAME_START;
144 buf[1] = 1; /* data size, command only */
147 mutex_lock(&ts->access_mutex);
148 ret = i2c_master_send(client, &buf[0], ARRAY_SIZE(buf));
149 mutex_unlock(&ts->access_mutex);
151 dev_err(&client->dev, "i2c send data request error: %d\n", ret);
158 static int zforce_send_wait(struct zforce_ts *ts, const char *buf, int len)
160 struct i2c_client *client = ts->client;
163 ret = mutex_trylock(&ts->command_mutex);
165 dev_err(&client->dev, "already waiting for a command\n");
169 dev_dbg(&client->dev, "sending %d bytes for command 0x%x\n",
172 ts->command_waiting = buf[2];
174 mutex_lock(&ts->access_mutex);
175 ret = i2c_master_send(client, buf, len);
176 mutex_unlock(&ts->access_mutex);
178 dev_err(&client->dev, "i2c send data request error: %d\n", ret);
182 dev_dbg(&client->dev, "waiting for result for command 0x%x\n", buf[2]);
184 if (wait_for_completion_timeout(&ts->command_done, WAIT_TIMEOUT) == 0) {
189 ret = ts->command_result;
192 mutex_unlock(&ts->command_mutex);
196 static int zforce_command_wait(struct zforce_ts *ts, u8 cmd)
198 struct i2c_client *client = ts->client;
202 dev_dbg(&client->dev, "%s: 0x%x\n", __func__, cmd);
204 buf[0] = FRAME_START;
205 buf[1] = 1; /* data size, command only */
208 ret = zforce_send_wait(ts, &buf[0], ARRAY_SIZE(buf));
210 dev_err(&client->dev, "i2c send data request error: %d\n", ret);
217 static int zforce_resolution(struct zforce_ts *ts, u16 x, u16 y)
219 struct i2c_client *client = ts->client;
220 char buf[7] = { FRAME_START, 5, COMMAND_RESOLUTION,
221 (x & 0xff), ((x >> 8) & 0xff),
222 (y & 0xff), ((y >> 8) & 0xff) };
224 dev_dbg(&client->dev, "set resolution to (%d,%d)\n", x, y);
226 return zforce_send_wait(ts, &buf[0], ARRAY_SIZE(buf));
229 static int zforce_scan_frequency(struct zforce_ts *ts, u16 idle, u16 finger,
232 struct i2c_client *client = ts->client;
233 char buf[9] = { FRAME_START, 7, COMMAND_SCANFREQ,
234 (idle & 0xff), ((idle >> 8) & 0xff),
235 (finger & 0xff), ((finger >> 8) & 0xff),
236 (stylus & 0xff), ((stylus >> 8) & 0xff) };
238 dev_dbg(&client->dev, "set scan frequency to (idle: %d, finger: %d, stylus: %d)\n",
239 idle, finger, stylus);
241 return zforce_send_wait(ts, &buf[0], ARRAY_SIZE(buf));
244 static int zforce_setconfig(struct zforce_ts *ts, char b1)
246 struct i2c_client *client = ts->client;
247 char buf[7] = { FRAME_START, 5, COMMAND_SETCONFIG,
250 dev_dbg(&client->dev, "set config to (%d)\n", b1);
252 return zforce_send_wait(ts, &buf[0], ARRAY_SIZE(buf));
255 static int zforce_start(struct zforce_ts *ts)
257 struct i2c_client *client = ts->client;
258 const struct zforce_ts_platdata *pdata = dev_get_platdata(&client->dev);
261 dev_dbg(&client->dev, "starting device\n");
263 ret = zforce_command_wait(ts, COMMAND_INITIALIZE);
265 dev_err(&client->dev, "Unable to initialize, %d\n", ret);
269 ret = zforce_resolution(ts, pdata->x_max, pdata->y_max);
271 dev_err(&client->dev, "Unable to set resolution, %d\n", ret);
275 ret = zforce_scan_frequency(ts, 10, 50, 50);
277 dev_err(&client->dev, "Unable to set scan frequency, %d\n",
282 if (zforce_setconfig(ts, SETCONFIG_DUALTOUCH)) {
283 dev_err(&client->dev, "Unable to set config\n");
287 /* start sending touch events */
288 ret = zforce_command(ts, COMMAND_DATAREQUEST);
290 dev_err(&client->dev, "Unable to request data\n");
295 * Per NN, initial cal. take max. of 200msec.
296 * Allow time to complete this calibration
303 zforce_command_wait(ts, COMMAND_DEACTIVATE);
307 static int zforce_stop(struct zforce_ts *ts)
309 struct i2c_client *client = ts->client;
312 dev_dbg(&client->dev, "stopping device\n");
314 /* Deactivates touch sensing and puts the device into sleep. */
315 ret = zforce_command_wait(ts, COMMAND_DEACTIVATE);
317 dev_err(&client->dev, "could not deactivate device, %d\n",
325 static int zforce_touch_event(struct zforce_ts *ts, u8 *payload)
327 struct i2c_client *client = ts->client;
328 const struct zforce_ts_platdata *pdata = dev_get_platdata(&client->dev);
329 struct zforce_point point;
330 int count, i, num = 0;
333 if (count > ZFORCE_REPORT_POINTS) {
334 dev_warn(&client->dev, "to many coordinates %d, expected max %d\n",
335 count, ZFORCE_REPORT_POINTS);
336 count = ZFORCE_REPORT_POINTS;
339 for (i = 0; i < count; i++) {
341 payload[9 * i + 2] << 8 | payload[9 * i + 1];
343 payload[9 * i + 4] << 8 | payload[9 * i + 3];
345 if (point.coord_x > pdata->x_max ||
346 point.coord_y > pdata->y_max) {
347 dev_warn(&client->dev, "coordinates (%d,%d) invalid\n",
348 point.coord_x, point.coord_y);
349 point.coord_x = point.coord_y = 0;
352 point.state = payload[9 * i + 5] & 0x03;
353 point.id = (payload[9 * i + 5] & 0xfc) >> 2;
355 /* determine touch major, minor and orientation */
356 point.area_major = max(payload[9 * i + 6],
358 point.area_minor = min(payload[9 * i + 6],
360 point.orientation = payload[9 * i + 6] > payload[9 * i + 7];
362 point.pressure = payload[9 * i + 8];
363 point.prblty = payload[9 * i + 9];
365 dev_dbg(&client->dev,
366 "point %d/%d: state %d, id %d, pressure %d, prblty %d, x %d, y %d, amajor %d, aminor %d, ori %d\n",
367 i, count, point.state, point.id,
368 point.pressure, point.prblty,
369 point.coord_x, point.coord_y,
370 point.area_major, point.area_minor,
373 /* the zforce id starts with "1", so needs to be decreased */
374 input_mt_slot(ts->input, point.id - 1);
376 input_mt_report_slot_state(ts->input, MT_TOOL_FINGER,
377 point.state != STATE_UP);
379 if (point.state != STATE_UP) {
380 input_report_abs(ts->input, ABS_MT_POSITION_X,
382 input_report_abs(ts->input, ABS_MT_POSITION_Y,
384 input_report_abs(ts->input, ABS_MT_TOUCH_MAJOR,
386 input_report_abs(ts->input, ABS_MT_TOUCH_MINOR,
388 input_report_abs(ts->input, ABS_MT_ORIENTATION,
394 input_mt_sync_frame(ts->input);
396 input_mt_report_finger_count(ts->input, num);
398 input_sync(ts->input);
403 static int zforce_read_packet(struct zforce_ts *ts, u8 *buf)
405 struct i2c_client *client = ts->client;
408 mutex_lock(&ts->access_mutex);
410 /* read 2 byte message header */
411 ret = i2c_master_recv(client, buf, 2);
413 dev_err(&client->dev, "error reading header: %d\n", ret);
417 if (buf[PAYLOAD_HEADER] != FRAME_START) {
418 dev_err(&client->dev, "invalid frame start: %d\n", buf[0]);
423 if (buf[PAYLOAD_LENGTH] <= 0 || buf[PAYLOAD_LENGTH] > 255) {
424 dev_err(&client->dev, "invalid payload length: %d\n",
425 buf[PAYLOAD_LENGTH]);
430 /* read the message */
431 ret = i2c_master_recv(client, &buf[PAYLOAD_BODY], buf[PAYLOAD_LENGTH]);
433 dev_err(&client->dev, "error reading payload: %d\n", ret);
437 dev_dbg(&client->dev, "read %d bytes for response command 0x%x\n",
438 buf[PAYLOAD_LENGTH], buf[PAYLOAD_BODY]);
441 mutex_unlock(&ts->access_mutex);
445 static void zforce_complete(struct zforce_ts *ts, int cmd, int result)
447 struct i2c_client *client = ts->client;
449 if (ts->command_waiting == cmd) {
450 dev_dbg(&client->dev, "completing command 0x%x\n", cmd);
451 ts->command_result = result;
452 complete(&ts->command_done);
454 dev_dbg(&client->dev, "command %d not for us\n", cmd);
458 static irqreturn_t zforce_interrupt(int irq, void *dev_id)
460 struct zforce_ts *ts = dev_id;
461 struct i2c_client *client = ts->client;
462 const struct zforce_ts_platdata *pdata = dev_get_platdata(&client->dev);
464 u8 payload_buffer[512];
468 * When suspended, emit a wakeup signal if necessary and return.
469 * Due to the level-interrupt we will get re-triggered later.
472 if (device_may_wakeup(&client->dev))
473 pm_wakeup_event(&client->dev, 500);
478 dev_dbg(&client->dev, "handling interrupt\n");
480 /* Don't emit wakeup events from commands run by zforce_suspend */
481 if (!ts->suspending && device_may_wakeup(&client->dev))
482 pm_stay_awake(&client->dev);
484 while (!gpio_get_value(pdata->gpio_int)) {
485 ret = zforce_read_packet(ts, payload_buffer);
487 dev_err(&client->dev, "could not read packet, ret: %d\n",
492 payload = &payload_buffer[PAYLOAD_BODY];
494 switch (payload[RESPONSE_ID]) {
495 case NOTIFICATION_TOUCH:
497 * Always report touch-events received while
498 * suspending, when being a wakeup source
500 if (ts->suspending && device_may_wakeup(&client->dev))
501 pm_wakeup_event(&client->dev, 500);
502 zforce_touch_event(ts, &payload[RESPONSE_DATA]);
505 case NOTIFICATION_BOOTCOMPLETE:
506 ts->boot_complete = payload[RESPONSE_DATA];
507 zforce_complete(ts, payload[RESPONSE_ID], 0);
510 case RESPONSE_INITIALIZE:
511 case RESPONSE_DEACTIVATE:
512 case RESPONSE_SETCONFIG:
513 case RESPONSE_RESOLUTION:
514 case RESPONSE_SCANFREQ:
515 zforce_complete(ts, payload[RESPONSE_ID],
516 payload[RESPONSE_DATA]);
519 case RESPONSE_STATUS:
521 * Version Payload Results
522 * [2:major] [2:minor] [2:build] [2:rev]
524 ts->version_major = (payload[RESPONSE_DATA + 1] << 8) |
525 payload[RESPONSE_DATA];
526 ts->version_minor = (payload[RESPONSE_DATA + 3] << 8) |
527 payload[RESPONSE_DATA + 2];
528 ts->version_build = (payload[RESPONSE_DATA + 5] << 8) |
529 payload[RESPONSE_DATA + 4];
530 ts->version_rev = (payload[RESPONSE_DATA + 7] << 8) |
531 payload[RESPONSE_DATA + 6];
532 dev_dbg(&ts->client->dev, "Firmware Version %04x:%04x %04x:%04x\n",
533 ts->version_major, ts->version_minor,
534 ts->version_build, ts->version_rev);
536 zforce_complete(ts, payload[RESPONSE_ID], 0);
539 case NOTIFICATION_INVALID_COMMAND:
540 dev_err(&ts->client->dev, "invalid command: 0x%x\n",
541 payload[RESPONSE_DATA]);
545 dev_err(&ts->client->dev, "unrecognized response id: 0x%x\n",
546 payload[RESPONSE_ID]);
551 if (!ts->suspending && device_may_wakeup(&client->dev))
552 pm_relax(&client->dev);
554 dev_dbg(&client->dev, "finished interrupt\n");
559 static int zforce_input_open(struct input_dev *dev)
561 struct zforce_ts *ts = input_get_drvdata(dev);
564 ret = zforce_start(ts);
571 static void zforce_input_close(struct input_dev *dev)
573 struct zforce_ts *ts = input_get_drvdata(dev);
574 struct i2c_client *client = ts->client;
577 ret = zforce_stop(ts);
579 dev_warn(&client->dev, "stopping zforce failed\n");
584 #ifdef CONFIG_PM_SLEEP
585 static int zforce_suspend(struct device *dev)
587 struct i2c_client *client = to_i2c_client(dev);
588 struct zforce_ts *ts = i2c_get_clientdata(client);
589 struct input_dev *input = ts->input;
592 mutex_lock(&input->mutex);
593 ts->suspending = true;
596 * When configured as a wakeup source device should always wake
597 * the system, therefore start device if necessary.
599 if (device_may_wakeup(&client->dev)) {
600 dev_dbg(&client->dev, "suspend while being a wakeup source\n");
602 /* Need to start device, if not open, to be a wakeup source. */
604 ret = zforce_start(ts);
609 enable_irq_wake(client->irq);
610 } else if (input->users) {
611 dev_dbg(&client->dev, "suspend without being a wakeup source\n");
613 ret = zforce_stop(ts);
617 disable_irq(client->irq);
620 ts->suspended = true;
623 ts->suspending = false;
624 mutex_unlock(&input->mutex);
629 static int zforce_resume(struct device *dev)
631 struct i2c_client *client = to_i2c_client(dev);
632 struct zforce_ts *ts = i2c_get_clientdata(client);
633 struct input_dev *input = ts->input;
636 mutex_lock(&input->mutex);
638 ts->suspended = false;
640 if (device_may_wakeup(&client->dev)) {
641 dev_dbg(&client->dev, "resume from being a wakeup source\n");
643 disable_irq_wake(client->irq);
645 /* need to stop device if it was not open on suspend */
647 ret = zforce_stop(ts);
651 } else if (input->users) {
652 dev_dbg(&client->dev, "resume without being a wakeup source\n");
654 enable_irq(client->irq);
656 ret = zforce_start(ts);
662 mutex_unlock(&input->mutex);
668 static SIMPLE_DEV_PM_OPS(zforce_pm_ops, zforce_suspend, zforce_resume);
670 static void zforce_reset(void *data)
672 struct zforce_ts *ts = data;
674 gpio_set_value(ts->pdata->gpio_rst, 0);
677 static int zforce_probe(struct i2c_client *client,
678 const struct i2c_device_id *id)
680 const struct zforce_ts_platdata *pdata = dev_get_platdata(&client->dev);
681 struct zforce_ts *ts;
682 struct input_dev *input_dev;
688 ts = devm_kzalloc(&client->dev, sizeof(struct zforce_ts), GFP_KERNEL);
692 ret = devm_gpio_request_one(&client->dev, pdata->gpio_int, GPIOF_IN,
695 dev_err(&client->dev, "request of gpio %d failed, %d\n",
696 pdata->gpio_int, ret);
700 ret = devm_gpio_request_one(&client->dev, pdata->gpio_rst,
701 GPIOF_OUT_INIT_LOW, "zforce_ts_rst");
703 dev_err(&client->dev, "request of gpio %d failed, %d\n",
704 pdata->gpio_rst, ret);
708 ret = devm_add_action(&client->dev, zforce_reset, ts);
710 dev_err(&client->dev, "failed to register reset action, %d\n",
715 snprintf(ts->phys, sizeof(ts->phys),
716 "%s/input0", dev_name(&client->dev));
718 input_dev = devm_input_allocate_device(&client->dev);
720 dev_err(&client->dev, "could not allocate input device\n");
724 mutex_init(&ts->access_mutex);
725 mutex_init(&ts->command_mutex);
729 ts->input = input_dev;
731 input_dev->name = "Neonode zForce touchscreen";
732 input_dev->phys = ts->phys;
733 input_dev->id.bustype = BUS_I2C;
735 input_dev->open = zforce_input_open;
736 input_dev->close = zforce_input_close;
738 __set_bit(EV_KEY, input_dev->evbit);
739 __set_bit(EV_SYN, input_dev->evbit);
740 __set_bit(EV_ABS, input_dev->evbit);
742 /* For multi touch */
743 input_set_abs_params(input_dev, ABS_MT_POSITION_X, 0,
745 input_set_abs_params(input_dev, ABS_MT_POSITION_Y, 0,
748 input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR, 0,
749 ZFORCE_MAX_AREA, 0, 0);
750 input_set_abs_params(input_dev, ABS_MT_TOUCH_MINOR, 0,
751 ZFORCE_MAX_AREA, 0, 0);
752 input_set_abs_params(input_dev, ABS_MT_ORIENTATION, 0, 1, 0, 0);
753 input_mt_init_slots(input_dev, ZFORCE_REPORT_POINTS, INPUT_MT_DIRECT);
755 input_set_drvdata(ts->input, ts);
757 init_completion(&ts->command_done);
760 * The zforce pulls the interrupt low when it has data ready.
761 * After it is triggered the isr thread runs until all the available
762 * packets have been read and the interrupt is high again.
763 * Therefore we can trigger the interrupt anytime it is low and do
764 * not need to limit it to the interrupt edge.
766 ret = devm_request_threaded_irq(&client->dev, client->irq, NULL,
768 IRQF_TRIGGER_LOW | IRQF_ONESHOT,
769 input_dev->name, ts);
771 dev_err(&client->dev, "irq %d request failed\n", client->irq);
775 i2c_set_clientdata(client, ts);
777 /* let the controller boot */
778 gpio_set_value(pdata->gpio_rst, 1);
780 ts->command_waiting = NOTIFICATION_BOOTCOMPLETE;
781 if (wait_for_completion_timeout(&ts->command_done, WAIT_TIMEOUT) == 0)
782 dev_warn(&client->dev, "bootcomplete timed out\n");
784 /* need to start device to get version information */
785 ret = zforce_command_wait(ts, COMMAND_INITIALIZE);
787 dev_err(&client->dev, "unable to initialize, %d\n", ret);
791 /* this gets the firmware version among other informations */
792 ret = zforce_command_wait(ts, COMMAND_STATUS);
794 dev_err(&client->dev, "couldn't get status, %d\n", ret);
799 /* stop device and put it into sleep until it is opened */
800 ret = zforce_stop(ts);
804 device_set_wakeup_capable(&client->dev, true);
806 ret = input_register_device(input_dev);
808 dev_err(&client->dev, "could not register input device, %d\n",
816 static struct i2c_device_id zforce_idtable[] = {
820 MODULE_DEVICE_TABLE(i2c, zforce_idtable);
822 static struct i2c_driver zforce_driver = {
824 .owner = THIS_MODULE,
826 .pm = &zforce_pm_ops,
828 .probe = zforce_probe,
829 .id_table = zforce_idtable,
832 module_i2c_driver(zforce_driver);
834 MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>");
835 MODULE_DESCRIPTION("zForce TouchScreen Driver");
836 MODULE_LICENSE("GPL");