1 // SPDX-License-Identifier: GPL-2.0-only
3 * Driver for Pixcir I2C touchscreen controllers.
5 * Copyright (C) 2010-2011 Pixcir, Inc.
8 #include <asm/unaligned.h>
9 #include <linux/delay.h>
10 #include <linux/gpio/consumer.h>
11 #include <linux/i2c.h>
12 #include <linux/input.h>
13 #include <linux/input/mt.h>
14 #include <linux/input/touchscreen.h>
15 #include <linux/interrupt.h>
16 #include <linux/of_device.h>
17 #include <linux/module.h>
18 #include <linux/slab.h>
20 #define PIXCIR_MAX_SLOTS 5 /* Max fingers supported by driver */
25 #define PIXCIR_REG_POWER_MODE 51
26 #define PIXCIR_REG_INT_MODE 52
30 * active: max scan speed
31 * idle: lower scan speed with automatic transition to active on touch
32 * halt: datasheet says sleep but this is more like halt as the chip
33 * clocks are cut and it can only be brought out of this mode
34 * using the RESET pin.
36 enum pixcir_power_mode {
42 #define PIXCIR_POWER_MODE_MASK 0x03
43 #define PIXCIR_POWER_ALLOW_IDLE (1UL << 2)
47 * periodical: interrupt is asserted periodicaly
48 * diff coordinates: interrupt is asserted when coordinates change
49 * level on touch: interrupt level asserted during touch
50 * pulse on touch: interrupt pulse asserted during touch
53 enum pixcir_int_mode {
54 PIXCIR_INT_PERIODICAL,
55 PIXCIR_INT_DIFF_COORD,
56 PIXCIR_INT_LEVEL_TOUCH,
57 PIXCIR_INT_PULSE_TOUCH,
60 #define PIXCIR_INT_MODE_MASK 0x03
61 #define PIXCIR_INT_ENABLE (1UL << 3)
62 #define PIXCIR_INT_POL_HIGH (1UL << 2)
65 * struct pixcir_i2c_chip_data - chip related data
66 * @max_fingers: Max number of fingers reported simultaneously by h/w
67 * @has_hw_ids: Hardware supports finger tracking IDs
70 struct pixcir_i2c_chip_data {
75 struct pixcir_i2c_ts_data {
76 struct i2c_client *client;
77 struct input_dev *input;
78 struct gpio_desc *gpio_attb;
79 struct gpio_desc *gpio_reset;
80 struct gpio_desc *gpio_enable;
81 struct gpio_desc *gpio_wake;
82 const struct pixcir_i2c_chip_data *chip;
83 struct touchscreen_properties prop;
87 struct pixcir_report_data {
89 struct input_mt_pos pos[PIXCIR_MAX_SLOTS];
90 int ids[PIXCIR_MAX_SLOTS];
93 static void pixcir_ts_parse(struct pixcir_i2c_ts_data *tsdata,
94 struct pixcir_report_data *report)
96 u8 rdbuf[2 + PIXCIR_MAX_SLOTS * 5];
102 const struct pixcir_i2c_chip_data *chip = tsdata->chip;
104 memset(report, 0, sizeof(struct pixcir_report_data));
106 i = chip->has_hw_ids ? 1 : 0;
107 readsize = 2 + tsdata->chip->max_fingers * (4 + i);
108 if (readsize > sizeof(rdbuf))
109 readsize = sizeof(rdbuf);
111 ret = i2c_master_send(tsdata->client, wrbuf, sizeof(wrbuf));
112 if (ret != sizeof(wrbuf)) {
113 dev_err(&tsdata->client->dev,
114 "%s: i2c_master_send failed(), ret=%d\n",
119 ret = i2c_master_recv(tsdata->client, rdbuf, readsize);
120 if (ret != readsize) {
121 dev_err(&tsdata->client->dev,
122 "%s: i2c_master_recv failed(), ret=%d\n",
127 touch = rdbuf[0] & 0x7;
128 if (touch > tsdata->chip->max_fingers)
129 touch = tsdata->chip->max_fingers;
131 report->num_touches = touch;
134 for (i = 0; i < touch; i++) {
135 touchscreen_set_mt_pos(&report->pos[i], &tsdata->prop,
136 get_unaligned_le16(bufptr),
137 get_unaligned_le16(bufptr + 2));
138 if (chip->has_hw_ids) {
139 report->ids[i] = bufptr[4];
147 static void pixcir_ts_report(struct pixcir_i2c_ts_data *ts,
148 struct pixcir_report_data *report)
150 int slots[PIXCIR_MAX_SLOTS];
152 struct device *dev = &ts->client->dev;
153 const struct pixcir_i2c_chip_data *chip = ts->chip;
155 n = report->num_touches;
156 if (n > PIXCIR_MAX_SLOTS)
157 n = PIXCIR_MAX_SLOTS;
159 if (!ts->chip->has_hw_ids)
160 input_mt_assign_slots(ts->input, slots, report->pos, n, 0);
162 for (i = 0; i < n; i++) {
163 if (chip->has_hw_ids) {
164 slot = input_mt_get_slot_by_key(ts->input,
167 dev_dbg(dev, "no free slot for id 0x%x\n",
175 input_mt_slot(ts->input, slot);
176 input_mt_report_slot_state(ts->input, MT_TOOL_FINGER, true);
178 input_report_abs(ts->input, ABS_MT_POSITION_X,
180 input_report_abs(ts->input, ABS_MT_POSITION_Y,
183 dev_dbg(dev, "%d: slot %d, x %d, y %d\n",
184 i, slot, report->pos[i].x, report->pos[i].y);
187 input_mt_sync_frame(ts->input);
188 input_sync(ts->input);
191 static irqreturn_t pixcir_ts_isr(int irq, void *dev_id)
193 struct pixcir_i2c_ts_data *tsdata = dev_id;
194 struct pixcir_report_data report;
196 while (tsdata->running) {
198 pixcir_ts_parse(tsdata, &report);
201 pixcir_ts_report(tsdata, &report);
203 if (gpiod_get_value_cansleep(tsdata->gpio_attb)) {
204 if (report.num_touches) {
206 * Last report with no finger up?
209 input_mt_sync_frame(tsdata->input);
210 input_sync(tsdata->input);
221 static void pixcir_reset(struct pixcir_i2c_ts_data *tsdata)
223 if (!IS_ERR_OR_NULL(tsdata->gpio_reset)) {
224 gpiod_set_value_cansleep(tsdata->gpio_reset, 1);
225 ndelay(100); /* datasheet section 1.2.3 says 80ns min. */
226 gpiod_set_value_cansleep(tsdata->gpio_reset, 0);
227 /* wait for controller ready. 100ms guess. */
232 static int pixcir_set_power_mode(struct pixcir_i2c_ts_data *ts,
233 enum pixcir_power_mode mode)
235 struct device *dev = &ts->client->dev;
238 if (mode == PIXCIR_POWER_ACTIVE || mode == PIXCIR_POWER_IDLE) {
240 gpiod_set_value_cansleep(ts->gpio_wake, 1);
243 ret = i2c_smbus_read_byte_data(ts->client, PIXCIR_REG_POWER_MODE);
245 dev_err(dev, "%s: can't read reg %d : %d\n",
246 __func__, PIXCIR_REG_POWER_MODE, ret);
250 ret &= ~PIXCIR_POWER_MODE_MASK;
253 /* Always AUTO_IDLE */
254 ret |= PIXCIR_POWER_ALLOW_IDLE;
256 ret = i2c_smbus_write_byte_data(ts->client, PIXCIR_REG_POWER_MODE, ret);
258 dev_err(dev, "%s: can't write reg %d : %d\n",
259 __func__, PIXCIR_REG_POWER_MODE, ret);
263 if (mode == PIXCIR_POWER_HALT) {
265 gpiod_set_value_cansleep(ts->gpio_wake, 0);
272 * Set the interrupt mode for the device i.e. ATTB line behaviour
274 * @polarity : 1 for active high, 0 for active low.
276 static int pixcir_set_int_mode(struct pixcir_i2c_ts_data *ts,
277 enum pixcir_int_mode mode, bool polarity)
279 struct device *dev = &ts->client->dev;
282 ret = i2c_smbus_read_byte_data(ts->client, PIXCIR_REG_INT_MODE);
284 dev_err(dev, "%s: can't read reg %d : %d\n",
285 __func__, PIXCIR_REG_INT_MODE, ret);
289 ret &= ~PIXCIR_INT_MODE_MASK;
293 ret |= PIXCIR_INT_POL_HIGH;
295 ret &= ~PIXCIR_INT_POL_HIGH;
297 ret = i2c_smbus_write_byte_data(ts->client, PIXCIR_REG_INT_MODE, ret);
299 dev_err(dev, "%s: can't write reg %d : %d\n",
300 __func__, PIXCIR_REG_INT_MODE, ret);
308 * Enable/disable interrupt generation
310 static int pixcir_int_enable(struct pixcir_i2c_ts_data *ts, bool enable)
312 struct device *dev = &ts->client->dev;
315 ret = i2c_smbus_read_byte_data(ts->client, PIXCIR_REG_INT_MODE);
317 dev_err(dev, "%s: can't read reg %d : %d\n",
318 __func__, PIXCIR_REG_INT_MODE, ret);
323 ret |= PIXCIR_INT_ENABLE;
325 ret &= ~PIXCIR_INT_ENABLE;
327 ret = i2c_smbus_write_byte_data(ts->client, PIXCIR_REG_INT_MODE, ret);
329 dev_err(dev, "%s: can't write reg %d : %d\n",
330 __func__, PIXCIR_REG_INT_MODE, ret);
337 static int pixcir_start(struct pixcir_i2c_ts_data *ts)
339 struct device *dev = &ts->client->dev;
342 if (ts->gpio_enable) {
343 gpiod_set_value_cansleep(ts->gpio_enable, 1);
347 /* LEVEL_TOUCH interrupt with active low polarity */
348 error = pixcir_set_int_mode(ts, PIXCIR_INT_LEVEL_TOUCH, 0);
350 dev_err(dev, "Failed to set interrupt mode: %d\n", error);
355 mb(); /* Update status before IRQ can fire */
357 /* enable interrupt generation */
358 error = pixcir_int_enable(ts, true);
360 dev_err(dev, "Failed to enable interrupt generation: %d\n",
368 static int pixcir_stop(struct pixcir_i2c_ts_data *ts)
372 /* Disable interrupt generation */
373 error = pixcir_int_enable(ts, false);
375 dev_err(&ts->client->dev,
376 "Failed to disable interrupt generation: %d\n",
381 /* Exit ISR if running, no more report parsing */
383 mb(); /* update status before we synchronize irq */
385 /* Wait till running ISR is complete */
386 synchronize_irq(ts->client->irq);
389 gpiod_set_value_cansleep(ts->gpio_enable, 0);
394 static int pixcir_input_open(struct input_dev *dev)
396 struct pixcir_i2c_ts_data *ts = input_get_drvdata(dev);
398 return pixcir_start(ts);
401 static void pixcir_input_close(struct input_dev *dev)
403 struct pixcir_i2c_ts_data *ts = input_get_drvdata(dev);
408 static int __maybe_unused pixcir_i2c_ts_suspend(struct device *dev)
410 struct i2c_client *client = to_i2c_client(dev);
411 struct pixcir_i2c_ts_data *ts = i2c_get_clientdata(client);
412 struct input_dev *input = ts->input;
415 mutex_lock(&input->mutex);
417 if (device_may_wakeup(&client->dev)) {
419 ret = pixcir_start(ts);
421 dev_err(dev, "Failed to start\n");
425 } else if (input->users) {
426 ret = pixcir_stop(ts);
430 mutex_unlock(&input->mutex);
435 static int __maybe_unused pixcir_i2c_ts_resume(struct device *dev)
437 struct i2c_client *client = to_i2c_client(dev);
438 struct pixcir_i2c_ts_data *ts = i2c_get_clientdata(client);
439 struct input_dev *input = ts->input;
442 mutex_lock(&input->mutex);
444 if (device_may_wakeup(&client->dev)) {
446 ret = pixcir_stop(ts);
448 dev_err(dev, "Failed to stop\n");
452 } else if (input->users) {
453 ret = pixcir_start(ts);
457 mutex_unlock(&input->mutex);
462 static SIMPLE_DEV_PM_OPS(pixcir_dev_pm_ops,
463 pixcir_i2c_ts_suspend, pixcir_i2c_ts_resume);
465 static int pixcir_i2c_ts_probe(struct i2c_client *client,
466 const struct i2c_device_id *id)
468 struct device *dev = &client->dev;
469 struct pixcir_i2c_ts_data *tsdata;
470 struct input_dev *input;
473 tsdata = devm_kzalloc(dev, sizeof(*tsdata), GFP_KERNEL);
477 tsdata->chip = device_get_match_data(dev);
478 if (!tsdata->chip && id)
479 tsdata->chip = (const void *)id->driver_data;
481 dev_err(dev, "can't locate chip data\n");
485 input = devm_input_allocate_device(dev);
487 dev_err(dev, "Failed to allocate input device\n");
491 tsdata->client = client;
492 tsdata->input = input;
494 input->name = client->name;
495 input->id.bustype = BUS_I2C;
496 input->open = pixcir_input_open;
497 input->close = pixcir_input_close;
499 input_set_capability(input, EV_ABS, ABS_MT_POSITION_X);
500 input_set_capability(input, EV_ABS, ABS_MT_POSITION_Y);
501 touchscreen_parse_properties(input, true, &tsdata->prop);
502 if (!input_abs_get_max(input, ABS_MT_POSITION_X) ||
503 !input_abs_get_max(input, ABS_MT_POSITION_Y)) {
504 dev_err(dev, "Touchscreen size is not specified\n");
508 error = input_mt_init_slots(input, tsdata->chip->max_fingers,
509 INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
511 dev_err(dev, "Error initializing Multi-Touch slots\n");
515 input_set_drvdata(input, tsdata);
517 tsdata->gpio_attb = devm_gpiod_get(dev, "attb", GPIOD_IN);
518 if (IS_ERR(tsdata->gpio_attb)) {
519 error = PTR_ERR(tsdata->gpio_attb);
520 if (error != -EPROBE_DEFER)
521 dev_err(dev, "Failed to request ATTB gpio: %d\n",
526 tsdata->gpio_reset = devm_gpiod_get_optional(dev, "reset",
528 if (IS_ERR(tsdata->gpio_reset)) {
529 error = PTR_ERR(tsdata->gpio_reset);
530 if (error != -EPROBE_DEFER)
531 dev_err(dev, "Failed to request RESET gpio: %d\n",
536 tsdata->gpio_wake = devm_gpiod_get_optional(dev, "wake",
538 if (IS_ERR(tsdata->gpio_wake)) {
539 error = PTR_ERR(tsdata->gpio_wake);
540 if (error != -EPROBE_DEFER)
541 dev_err(dev, "Failed to get wake gpio: %d\n", error);
545 tsdata->gpio_enable = devm_gpiod_get_optional(dev, "enable",
547 if (IS_ERR(tsdata->gpio_enable)) {
548 error = PTR_ERR(tsdata->gpio_enable);
549 if (error != -EPROBE_DEFER)
550 dev_err(dev, "Failed to get enable gpio: %d\n", error);
554 if (tsdata->gpio_enable)
557 error = devm_request_threaded_irq(dev, client->irq, NULL, pixcir_ts_isr,
558 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
559 client->name, tsdata);
561 dev_err(dev, "failed to request irq %d\n", client->irq);
565 pixcir_reset(tsdata);
567 /* Always be in IDLE mode to save power, device supports auto wake */
568 error = pixcir_set_power_mode(tsdata, PIXCIR_POWER_IDLE);
570 dev_err(dev, "Failed to set IDLE mode\n");
574 /* Stop device till opened */
575 error = pixcir_stop(tsdata);
579 error = input_register_device(input);
583 i2c_set_clientdata(client, tsdata);
588 static const struct pixcir_i2c_chip_data pixcir_ts_data = {
590 /* no hw id support */
593 static const struct pixcir_i2c_chip_data pixcir_tangoc_data = {
598 static const struct i2c_device_id pixcir_i2c_ts_id[] = {
599 { "pixcir_ts", (unsigned long) &pixcir_ts_data },
600 { "pixcir_tangoc", (unsigned long) &pixcir_tangoc_data },
603 MODULE_DEVICE_TABLE(i2c, pixcir_i2c_ts_id);
606 static const struct of_device_id pixcir_of_match[] = {
607 { .compatible = "pixcir,pixcir_ts", .data = &pixcir_ts_data },
608 { .compatible = "pixcir,pixcir_tangoc", .data = &pixcir_tangoc_data },
611 MODULE_DEVICE_TABLE(of, pixcir_of_match);
614 static struct i2c_driver pixcir_i2c_ts_driver = {
617 .pm = &pixcir_dev_pm_ops,
618 .of_match_table = of_match_ptr(pixcir_of_match),
620 .probe = pixcir_i2c_ts_probe,
621 .id_table = pixcir_i2c_ts_id,
624 module_i2c_driver(pixcir_i2c_ts_driver);
626 MODULE_AUTHOR("Jianchun Bian <jcbian@pixcir.com.cn>, Dequan Meng <dqmeng@pixcir.com.cn>");
627 MODULE_DESCRIPTION("Pixcir I2C Touchscreen Driver");
628 MODULE_LICENSE("GPL");