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_irq(int irq, void *dev_id)
460 struct zforce_ts *ts = dev_id;
461 struct i2c_client *client = ts->client;
463 if (ts->suspended && device_may_wakeup(&client->dev))
464 pm_wakeup_event(&client->dev, 500);
466 return IRQ_WAKE_THREAD;
469 static irqreturn_t zforce_irq_thread(int irq, void *dev_id)
471 struct zforce_ts *ts = dev_id;
472 struct i2c_client *client = ts->client;
473 const struct zforce_ts_platdata *pdata = dev_get_platdata(&client->dev);
475 u8 payload_buffer[512];
479 * When still suspended, return.
480 * Due to the level-interrupt we will get re-triggered later.
487 dev_dbg(&client->dev, "handling interrupt\n");
489 /* Don't emit wakeup events from commands run by zforce_suspend */
490 if (!ts->suspending && device_may_wakeup(&client->dev))
491 pm_stay_awake(&client->dev);
493 while (!gpio_get_value(pdata->gpio_int)) {
494 ret = zforce_read_packet(ts, payload_buffer);
496 dev_err(&client->dev, "could not read packet, ret: %d\n",
501 payload = &payload_buffer[PAYLOAD_BODY];
503 switch (payload[RESPONSE_ID]) {
504 case NOTIFICATION_TOUCH:
506 * Always report touch-events received while
507 * suspending, when being a wakeup source
509 if (ts->suspending && device_may_wakeup(&client->dev))
510 pm_wakeup_event(&client->dev, 500);
511 zforce_touch_event(ts, &payload[RESPONSE_DATA]);
514 case NOTIFICATION_BOOTCOMPLETE:
515 ts->boot_complete = payload[RESPONSE_DATA];
516 zforce_complete(ts, payload[RESPONSE_ID], 0);
519 case RESPONSE_INITIALIZE:
520 case RESPONSE_DEACTIVATE:
521 case RESPONSE_SETCONFIG:
522 case RESPONSE_RESOLUTION:
523 case RESPONSE_SCANFREQ:
524 zforce_complete(ts, payload[RESPONSE_ID],
525 payload[RESPONSE_DATA]);
528 case RESPONSE_STATUS:
530 * Version Payload Results
531 * [2:major] [2:minor] [2:build] [2:rev]
533 ts->version_major = (payload[RESPONSE_DATA + 1] << 8) |
534 payload[RESPONSE_DATA];
535 ts->version_minor = (payload[RESPONSE_DATA + 3] << 8) |
536 payload[RESPONSE_DATA + 2];
537 ts->version_build = (payload[RESPONSE_DATA + 5] << 8) |
538 payload[RESPONSE_DATA + 4];
539 ts->version_rev = (payload[RESPONSE_DATA + 7] << 8) |
540 payload[RESPONSE_DATA + 6];
541 dev_dbg(&ts->client->dev, "Firmware Version %04x:%04x %04x:%04x\n",
542 ts->version_major, ts->version_minor,
543 ts->version_build, ts->version_rev);
545 zforce_complete(ts, payload[RESPONSE_ID], 0);
548 case NOTIFICATION_INVALID_COMMAND:
549 dev_err(&ts->client->dev, "invalid command: 0x%x\n",
550 payload[RESPONSE_DATA]);
554 dev_err(&ts->client->dev, "unrecognized response id: 0x%x\n",
555 payload[RESPONSE_ID]);
560 if (!ts->suspending && device_may_wakeup(&client->dev))
561 pm_relax(&client->dev);
563 dev_dbg(&client->dev, "finished interrupt\n");
568 static int zforce_input_open(struct input_dev *dev)
570 struct zforce_ts *ts = input_get_drvdata(dev);
573 ret = zforce_start(ts);
580 static void zforce_input_close(struct input_dev *dev)
582 struct zforce_ts *ts = input_get_drvdata(dev);
583 struct i2c_client *client = ts->client;
586 ret = zforce_stop(ts);
588 dev_warn(&client->dev, "stopping zforce failed\n");
593 #ifdef CONFIG_PM_SLEEP
594 static int zforce_suspend(struct device *dev)
596 struct i2c_client *client = to_i2c_client(dev);
597 struct zforce_ts *ts = i2c_get_clientdata(client);
598 struct input_dev *input = ts->input;
601 mutex_lock(&input->mutex);
602 ts->suspending = true;
605 * When configured as a wakeup source device should always wake
606 * the system, therefore start device if necessary.
608 if (device_may_wakeup(&client->dev)) {
609 dev_dbg(&client->dev, "suspend while being a wakeup source\n");
611 /* Need to start device, if not open, to be a wakeup source. */
613 ret = zforce_start(ts);
618 enable_irq_wake(client->irq);
619 } else if (input->users) {
620 dev_dbg(&client->dev, "suspend without being a wakeup source\n");
622 ret = zforce_stop(ts);
626 disable_irq(client->irq);
629 ts->suspended = true;
632 ts->suspending = false;
633 mutex_unlock(&input->mutex);
638 static int zforce_resume(struct device *dev)
640 struct i2c_client *client = to_i2c_client(dev);
641 struct zforce_ts *ts = i2c_get_clientdata(client);
642 struct input_dev *input = ts->input;
645 mutex_lock(&input->mutex);
647 ts->suspended = false;
649 if (device_may_wakeup(&client->dev)) {
650 dev_dbg(&client->dev, "resume from being a wakeup source\n");
652 disable_irq_wake(client->irq);
654 /* need to stop device if it was not open on suspend */
656 ret = zforce_stop(ts);
660 } else if (input->users) {
661 dev_dbg(&client->dev, "resume without being a wakeup source\n");
663 enable_irq(client->irq);
665 ret = zforce_start(ts);
671 mutex_unlock(&input->mutex);
677 static SIMPLE_DEV_PM_OPS(zforce_pm_ops, zforce_suspend, zforce_resume);
679 static void zforce_reset(void *data)
681 struct zforce_ts *ts = data;
683 gpio_set_value(ts->pdata->gpio_rst, 0);
686 static int zforce_probe(struct i2c_client *client,
687 const struct i2c_device_id *id)
689 const struct zforce_ts_platdata *pdata = dev_get_platdata(&client->dev);
690 struct zforce_ts *ts;
691 struct input_dev *input_dev;
697 ts = devm_kzalloc(&client->dev, sizeof(struct zforce_ts), GFP_KERNEL);
701 ret = devm_gpio_request_one(&client->dev, pdata->gpio_int, GPIOF_IN,
704 dev_err(&client->dev, "request of gpio %d failed, %d\n",
705 pdata->gpio_int, ret);
709 ret = devm_gpio_request_one(&client->dev, pdata->gpio_rst,
710 GPIOF_OUT_INIT_LOW, "zforce_ts_rst");
712 dev_err(&client->dev, "request of gpio %d failed, %d\n",
713 pdata->gpio_rst, ret);
717 ret = devm_add_action(&client->dev, zforce_reset, ts);
719 dev_err(&client->dev, "failed to register reset action, %d\n",
724 snprintf(ts->phys, sizeof(ts->phys),
725 "%s/input0", dev_name(&client->dev));
727 input_dev = devm_input_allocate_device(&client->dev);
729 dev_err(&client->dev, "could not allocate input device\n");
733 mutex_init(&ts->access_mutex);
734 mutex_init(&ts->command_mutex);
738 ts->input = input_dev;
740 input_dev->name = "Neonode zForce touchscreen";
741 input_dev->phys = ts->phys;
742 input_dev->id.bustype = BUS_I2C;
744 input_dev->open = zforce_input_open;
745 input_dev->close = zforce_input_close;
747 __set_bit(EV_KEY, input_dev->evbit);
748 __set_bit(EV_SYN, input_dev->evbit);
749 __set_bit(EV_ABS, input_dev->evbit);
751 /* For multi touch */
752 input_set_abs_params(input_dev, ABS_MT_POSITION_X, 0,
754 input_set_abs_params(input_dev, ABS_MT_POSITION_Y, 0,
757 input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR, 0,
758 ZFORCE_MAX_AREA, 0, 0);
759 input_set_abs_params(input_dev, ABS_MT_TOUCH_MINOR, 0,
760 ZFORCE_MAX_AREA, 0, 0);
761 input_set_abs_params(input_dev, ABS_MT_ORIENTATION, 0, 1, 0, 0);
762 input_mt_init_slots(input_dev, ZFORCE_REPORT_POINTS, INPUT_MT_DIRECT);
764 input_set_drvdata(ts->input, ts);
766 init_completion(&ts->command_done);
769 * The zforce pulls the interrupt low when it has data ready.
770 * After it is triggered the isr thread runs until all the available
771 * packets have been read and the interrupt is high again.
772 * Therefore we can trigger the interrupt anytime it is low and do
773 * not need to limit it to the interrupt edge.
775 ret = devm_request_threaded_irq(&client->dev, client->irq,
776 zforce_irq, zforce_irq_thread,
777 IRQF_TRIGGER_LOW | IRQF_ONESHOT,
778 input_dev->name, ts);
780 dev_err(&client->dev, "irq %d request failed\n", client->irq);
784 i2c_set_clientdata(client, ts);
786 /* let the controller boot */
787 gpio_set_value(pdata->gpio_rst, 1);
789 ts->command_waiting = NOTIFICATION_BOOTCOMPLETE;
790 if (wait_for_completion_timeout(&ts->command_done, WAIT_TIMEOUT) == 0)
791 dev_warn(&client->dev, "bootcomplete timed out\n");
793 /* need to start device to get version information */
794 ret = zforce_command_wait(ts, COMMAND_INITIALIZE);
796 dev_err(&client->dev, "unable to initialize, %d\n", ret);
800 /* this gets the firmware version among other informations */
801 ret = zforce_command_wait(ts, COMMAND_STATUS);
803 dev_err(&client->dev, "couldn't get status, %d\n", ret);
808 /* stop device and put it into sleep until it is opened */
809 ret = zforce_stop(ts);
813 device_set_wakeup_capable(&client->dev, true);
815 ret = input_register_device(input_dev);
817 dev_err(&client->dev, "could not register input device, %d\n",
825 static struct i2c_device_id zforce_idtable[] = {
829 MODULE_DEVICE_TABLE(i2c, zforce_idtable);
831 static struct i2c_driver zforce_driver = {
833 .owner = THIS_MODULE,
835 .pm = &zforce_pm_ops,
837 .probe = zforce_probe,
838 .id_table = zforce_idtable,
841 module_i2c_driver(zforce_driver);
843 MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>");
844 MODULE_DESCRIPTION("zForce TouchScreen Driver");
845 MODULE_LICENSE("GPL");