| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * Driver for Pixcir I2C touchscreen controllers. |
| * |
| * Copyright (C) 2010-2011 Pixcir, Inc. |
| */ |
| |
| #include <asm/unaligned.h> |
| #include <linux/delay.h> |
| #include <linux/gpio/consumer.h> |
| #include <linux/i2c.h> |
| #include <linux/input.h> |
| #include <linux/input/mt.h> |
| #include <linux/input/touchscreen.h> |
| #include <linux/interrupt.h> |
| #include <linux/module.h> |
| #include <linux/of.h> |
| #include <linux/slab.h> |
| |
| #define PIXCIR_MAX_SLOTS 5 /* Max fingers supported by driver */ |
| |
| /* |
| * Register map |
| */ |
| #define PIXCIR_REG_POWER_MODE 51 |
| #define PIXCIR_REG_INT_MODE 52 |
| |
| /* |
| * Power modes: |
| * active: max scan speed |
| * idle: lower scan speed with automatic transition to active on touch |
| * halt: datasheet says sleep but this is more like halt as the chip |
| * clocks are cut and it can only be brought out of this mode |
| * using the RESET pin. |
| */ |
| enum pixcir_power_mode { |
| PIXCIR_POWER_ACTIVE, |
| PIXCIR_POWER_IDLE, |
| PIXCIR_POWER_HALT, |
| }; |
| |
| #define PIXCIR_POWER_MODE_MASK 0x03 |
| #define PIXCIR_POWER_ALLOW_IDLE (1UL << 2) |
| |
| /* |
| * Interrupt modes: |
| * periodical: interrupt is asserted periodicaly |
| * diff coordinates: interrupt is asserted when coordinates change |
| * level on touch: interrupt level asserted during touch |
| * pulse on touch: interrupt pulse asserted during touch |
| * |
| */ |
| enum pixcir_int_mode { |
| PIXCIR_INT_PERIODICAL, |
| PIXCIR_INT_DIFF_COORD, |
| PIXCIR_INT_LEVEL_TOUCH, |
| PIXCIR_INT_PULSE_TOUCH, |
| }; |
| |
| #define PIXCIR_INT_MODE_MASK 0x03 |
| #define PIXCIR_INT_ENABLE (1UL << 3) |
| #define PIXCIR_INT_POL_HIGH (1UL << 2) |
| |
| /** |
| * struct pixcir_i2c_chip_data - chip related data |
| * @max_fingers: Max number of fingers reported simultaneously by h/w |
| * @has_hw_ids: Hardware supports finger tracking IDs |
| * |
| */ |
| struct pixcir_i2c_chip_data { |
| u8 max_fingers; |
| bool has_hw_ids; |
| }; |
| |
| struct pixcir_i2c_ts_data { |
| struct i2c_client *client; |
| struct input_dev *input; |
| struct gpio_desc *gpio_attb; |
| struct gpio_desc *gpio_reset; |
| struct gpio_desc *gpio_enable; |
| struct gpio_desc *gpio_wake; |
| const struct pixcir_i2c_chip_data *chip; |
| struct touchscreen_properties prop; |
| bool running; |
| }; |
| |
| struct pixcir_report_data { |
| int num_touches; |
| struct input_mt_pos pos[PIXCIR_MAX_SLOTS]; |
| int ids[PIXCIR_MAX_SLOTS]; |
| }; |
| |
| static void pixcir_ts_parse(struct pixcir_i2c_ts_data *tsdata, |
| struct pixcir_report_data *report) |
| { |
| u8 rdbuf[2 + PIXCIR_MAX_SLOTS * 5]; |
| u8 wrbuf[1] = { 0 }; |
| u8 *bufptr; |
| u8 touch; |
| int ret, i; |
| int readsize; |
| const struct pixcir_i2c_chip_data *chip = tsdata->chip; |
| |
| memset(report, 0, sizeof(struct pixcir_report_data)); |
| |
| i = chip->has_hw_ids ? 1 : 0; |
| readsize = 2 + tsdata->chip->max_fingers * (4 + i); |
| if (readsize > sizeof(rdbuf)) |
| readsize = sizeof(rdbuf); |
| |
| ret = i2c_master_send(tsdata->client, wrbuf, sizeof(wrbuf)); |
| if (ret != sizeof(wrbuf)) { |
| dev_err(&tsdata->client->dev, |
| "%s: i2c_master_send failed(), ret=%d\n", |
| __func__, ret); |
| return; |
| } |
| |
| ret = i2c_master_recv(tsdata->client, rdbuf, readsize); |
| if (ret != readsize) { |
| dev_err(&tsdata->client->dev, |
| "%s: i2c_master_recv failed(), ret=%d\n", |
| __func__, ret); |
| return; |
| } |
| |
| touch = rdbuf[0] & 0x7; |
| if (touch > tsdata->chip->max_fingers) |
| touch = tsdata->chip->max_fingers; |
| |
| report->num_touches = touch; |
| bufptr = &rdbuf[2]; |
| |
| for (i = 0; i < touch; i++) { |
| touchscreen_set_mt_pos(&report->pos[i], &tsdata->prop, |
| get_unaligned_le16(bufptr), |
| get_unaligned_le16(bufptr + 2)); |
| if (chip->has_hw_ids) { |
| report->ids[i] = bufptr[4]; |
| bufptr = bufptr + 5; |
| } else { |
| bufptr = bufptr + 4; |
| } |
| } |
| } |
| |
| static void pixcir_ts_report(struct pixcir_i2c_ts_data *ts, |
| struct pixcir_report_data *report) |
| { |
| int slots[PIXCIR_MAX_SLOTS]; |
| int n, i, slot; |
| struct device *dev = &ts->client->dev; |
| const struct pixcir_i2c_chip_data *chip = ts->chip; |
| |
| n = report->num_touches; |
| if (n > PIXCIR_MAX_SLOTS) |
| n = PIXCIR_MAX_SLOTS; |
| |
| if (!ts->chip->has_hw_ids) |
| input_mt_assign_slots(ts->input, slots, report->pos, n, 0); |
| |
| for (i = 0; i < n; i++) { |
| if (chip->has_hw_ids) { |
| slot = input_mt_get_slot_by_key(ts->input, |
| report->ids[i]); |
| if (slot < 0) { |
| dev_dbg(dev, "no free slot for id 0x%x\n", |
| report->ids[i]); |
| continue; |
| } |
| } else { |
| slot = slots[i]; |
| } |
| |
| input_mt_slot(ts->input, slot); |
| input_mt_report_slot_state(ts->input, MT_TOOL_FINGER, true); |
| |
| input_report_abs(ts->input, ABS_MT_POSITION_X, |
| report->pos[i].x); |
| input_report_abs(ts->input, ABS_MT_POSITION_Y, |
| report->pos[i].y); |
| |
| dev_dbg(dev, "%d: slot %d, x %d, y %d\n", |
| i, slot, report->pos[i].x, report->pos[i].y); |
| } |
| |
| input_mt_sync_frame(ts->input); |
| input_sync(ts->input); |
| } |
| |
| static irqreturn_t pixcir_ts_isr(int irq, void *dev_id) |
| { |
| struct pixcir_i2c_ts_data *tsdata = dev_id; |
| struct pixcir_report_data report; |
| |
| while (tsdata->running) { |
| /* parse packet */ |
| pixcir_ts_parse(tsdata, &report); |
| |
| /* report it */ |
| pixcir_ts_report(tsdata, &report); |
| |
| if (gpiod_get_value_cansleep(tsdata->gpio_attb)) { |
| if (report.num_touches) { |
| /* |
| * Last report with no finger up? |
| * Do it now then. |
| */ |
| input_mt_sync_frame(tsdata->input); |
| input_sync(tsdata->input); |
| } |
| break; |
| } |
| |
| msleep(20); |
| } |
| |
| return IRQ_HANDLED; |
| } |
| |
| static void pixcir_reset(struct pixcir_i2c_ts_data *tsdata) |
| { |
| if (!IS_ERR_OR_NULL(tsdata->gpio_reset)) { |
| gpiod_set_value_cansleep(tsdata->gpio_reset, 1); |
| ndelay(100); /* datasheet section 1.2.3 says 80ns min. */ |
| gpiod_set_value_cansleep(tsdata->gpio_reset, 0); |
| /* wait for controller ready. 100ms guess. */ |
| msleep(100); |
| } |
| } |
| |
| static int pixcir_set_power_mode(struct pixcir_i2c_ts_data *ts, |
| enum pixcir_power_mode mode) |
| { |
| struct device *dev = &ts->client->dev; |
| int ret; |
| |
| if (mode == PIXCIR_POWER_ACTIVE || mode == PIXCIR_POWER_IDLE) { |
| if (ts->gpio_wake) |
| gpiod_set_value_cansleep(ts->gpio_wake, 1); |
| } |
| |
| ret = i2c_smbus_read_byte_data(ts->client, PIXCIR_REG_POWER_MODE); |
| if (ret < 0) { |
| dev_err(dev, "%s: can't read reg %d : %d\n", |
| __func__, PIXCIR_REG_POWER_MODE, ret); |
| return ret; |
| } |
| |
| ret &= ~PIXCIR_POWER_MODE_MASK; |
| ret |= mode; |
| |
| /* Always AUTO_IDLE */ |
| ret |= PIXCIR_POWER_ALLOW_IDLE; |
| |
| ret = i2c_smbus_write_byte_data(ts->client, PIXCIR_REG_POWER_MODE, ret); |
| if (ret < 0) { |
| dev_err(dev, "%s: can't write reg %d : %d\n", |
| __func__, PIXCIR_REG_POWER_MODE, ret); |
| return ret; |
| } |
| |
| if (mode == PIXCIR_POWER_HALT) { |
| if (ts->gpio_wake) |
| gpiod_set_value_cansleep(ts->gpio_wake, 0); |
| } |
| |
| return 0; |
| } |
| |
| /* |
| * Set the interrupt mode for the device i.e. ATTB line behaviour |
| * |
| * @polarity : 1 for active high, 0 for active low. |
| */ |
| static int pixcir_set_int_mode(struct pixcir_i2c_ts_data *ts, |
| enum pixcir_int_mode mode, bool polarity) |
| { |
| struct device *dev = &ts->client->dev; |
| int ret; |
| |
| ret = i2c_smbus_read_byte_data(ts->client, PIXCIR_REG_INT_MODE); |
| if (ret < 0) { |
| dev_err(dev, "%s: can't read reg %d : %d\n", |
| __func__, PIXCIR_REG_INT_MODE, ret); |
| return ret; |
| } |
| |
| ret &= ~PIXCIR_INT_MODE_MASK; |
| ret |= mode; |
| |
| if (polarity) |
| ret |= PIXCIR_INT_POL_HIGH; |
| else |
| ret &= ~PIXCIR_INT_POL_HIGH; |
| |
| ret = i2c_smbus_write_byte_data(ts->client, PIXCIR_REG_INT_MODE, ret); |
| if (ret < 0) { |
| dev_err(dev, "%s: can't write reg %d : %d\n", |
| __func__, PIXCIR_REG_INT_MODE, ret); |
| return ret; |
| } |
| |
| return 0; |
| } |
| |
| /* |
| * Enable/disable interrupt generation |
| */ |
| static int pixcir_int_enable(struct pixcir_i2c_ts_data *ts, bool enable) |
| { |
| struct device *dev = &ts->client->dev; |
| int ret; |
| |
| ret = i2c_smbus_read_byte_data(ts->client, PIXCIR_REG_INT_MODE); |
| if (ret < 0) { |
| dev_err(dev, "%s: can't read reg %d : %d\n", |
| __func__, PIXCIR_REG_INT_MODE, ret); |
| return ret; |
| } |
| |
| if (enable) |
| ret |= PIXCIR_INT_ENABLE; |
| else |
| ret &= ~PIXCIR_INT_ENABLE; |
| |
| ret = i2c_smbus_write_byte_data(ts->client, PIXCIR_REG_INT_MODE, ret); |
| if (ret < 0) { |
| dev_err(dev, "%s: can't write reg %d : %d\n", |
| __func__, PIXCIR_REG_INT_MODE, ret); |
| return ret; |
| } |
| |
| return 0; |
| } |
| |
| static int pixcir_start(struct pixcir_i2c_ts_data *ts) |
| { |
| struct device *dev = &ts->client->dev; |
| int error; |
| |
| if (ts->gpio_enable) { |
| gpiod_set_value_cansleep(ts->gpio_enable, 1); |
| msleep(100); |
| } |
| |
| /* LEVEL_TOUCH interrupt with active low polarity */ |
| error = pixcir_set_int_mode(ts, PIXCIR_INT_LEVEL_TOUCH, 0); |
| if (error) { |
| dev_err(dev, "Failed to set interrupt mode: %d\n", error); |
| return error; |
| } |
| |
| ts->running = true; |
| mb(); /* Update status before IRQ can fire */ |
| |
| /* enable interrupt generation */ |
| error = pixcir_int_enable(ts, true); |
| if (error) { |
| dev_err(dev, "Failed to enable interrupt generation: %d\n", |
| error); |
| return error; |
| } |
| |
| return 0; |
| } |
| |
| static int pixcir_stop(struct pixcir_i2c_ts_data *ts) |
| { |
| int error; |
| |
| /* Disable interrupt generation */ |
| error = pixcir_int_enable(ts, false); |
| if (error) { |
| dev_err(&ts->client->dev, |
| "Failed to disable interrupt generation: %d\n", |
| error); |
| return error; |
| } |
| |
| /* Exit ISR if running, no more report parsing */ |
| ts->running = false; |
| mb(); /* update status before we synchronize irq */ |
| |
| /* Wait till running ISR is complete */ |
| synchronize_irq(ts->client->irq); |
| |
| if (ts->gpio_enable) |
| gpiod_set_value_cansleep(ts->gpio_enable, 0); |
| |
| return 0; |
| } |
| |
| static int pixcir_input_open(struct input_dev *dev) |
| { |
| struct pixcir_i2c_ts_data *ts = input_get_drvdata(dev); |
| |
| return pixcir_start(ts); |
| } |
| |
| static void pixcir_input_close(struct input_dev *dev) |
| { |
| struct pixcir_i2c_ts_data *ts = input_get_drvdata(dev); |
| |
| pixcir_stop(ts); |
| } |
| |
| static int pixcir_i2c_ts_suspend(struct device *dev) |
| { |
| struct i2c_client *client = to_i2c_client(dev); |
| struct pixcir_i2c_ts_data *ts = i2c_get_clientdata(client); |
| struct input_dev *input = ts->input; |
| int ret = 0; |
| |
| mutex_lock(&input->mutex); |
| |
| if (device_may_wakeup(&client->dev)) { |
| if (!input_device_enabled(input)) { |
| ret = pixcir_start(ts); |
| if (ret) { |
| dev_err(dev, "Failed to start\n"); |
| goto unlock; |
| } |
| } |
| } else if (input_device_enabled(input)) { |
| ret = pixcir_stop(ts); |
| } |
| |
| unlock: |
| mutex_unlock(&input->mutex); |
| |
| return ret; |
| } |
| |
| static int pixcir_i2c_ts_resume(struct device *dev) |
| { |
| struct i2c_client *client = to_i2c_client(dev); |
| struct pixcir_i2c_ts_data *ts = i2c_get_clientdata(client); |
| struct input_dev *input = ts->input; |
| int ret = 0; |
| |
| mutex_lock(&input->mutex); |
| |
| if (device_may_wakeup(&client->dev)) { |
| if (!input_device_enabled(input)) { |
| ret = pixcir_stop(ts); |
| if (ret) { |
| dev_err(dev, "Failed to stop\n"); |
| goto unlock; |
| } |
| } |
| } else if (input_device_enabled(input)) { |
| ret = pixcir_start(ts); |
| } |
| |
| unlock: |
| mutex_unlock(&input->mutex); |
| |
| return ret; |
| } |
| |
| static DEFINE_SIMPLE_DEV_PM_OPS(pixcir_dev_pm_ops, |
| pixcir_i2c_ts_suspend, pixcir_i2c_ts_resume); |
| |
| static int pixcir_i2c_ts_probe(struct i2c_client *client) |
| { |
| const struct i2c_device_id *id = i2c_client_get_device_id(client); |
| struct device *dev = &client->dev; |
| struct pixcir_i2c_ts_data *tsdata; |
| struct input_dev *input; |
| int error; |
| |
| tsdata = devm_kzalloc(dev, sizeof(*tsdata), GFP_KERNEL); |
| if (!tsdata) |
| return -ENOMEM; |
| |
| tsdata->chip = device_get_match_data(dev); |
| if (!tsdata->chip && id) |
| tsdata->chip = (const void *)id->driver_data; |
| if (!tsdata->chip) { |
| dev_err(dev, "can't locate chip data\n"); |
| return -EINVAL; |
| } |
| |
| input = devm_input_allocate_device(dev); |
| if (!input) { |
| dev_err(dev, "Failed to allocate input device\n"); |
| return -ENOMEM; |
| } |
| |
| tsdata->client = client; |
| tsdata->input = input; |
| |
| input->name = client->name; |
| input->id.bustype = BUS_I2C; |
| input->open = pixcir_input_open; |
| input->close = pixcir_input_close; |
| |
| input_set_capability(input, EV_ABS, ABS_MT_POSITION_X); |
| input_set_capability(input, EV_ABS, ABS_MT_POSITION_Y); |
| touchscreen_parse_properties(input, true, &tsdata->prop); |
| if (!input_abs_get_max(input, ABS_MT_POSITION_X) || |
| !input_abs_get_max(input, ABS_MT_POSITION_Y)) { |
| dev_err(dev, "Touchscreen size is not specified\n"); |
| return -EINVAL; |
| } |
| |
| error = input_mt_init_slots(input, tsdata->chip->max_fingers, |
| INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED); |
| if (error) { |
| dev_err(dev, "Error initializing Multi-Touch slots\n"); |
| return error; |
| } |
| |
| input_set_drvdata(input, tsdata); |
| |
| tsdata->gpio_attb = devm_gpiod_get(dev, "attb", GPIOD_IN); |
| if (IS_ERR(tsdata->gpio_attb)) |
| return dev_err_probe(dev, PTR_ERR(tsdata->gpio_attb), |
| "Failed to request ATTB gpio\n"); |
| |
| tsdata->gpio_reset = devm_gpiod_get_optional(dev, "reset", |
| GPIOD_OUT_LOW); |
| if (IS_ERR(tsdata->gpio_reset)) |
| return dev_err_probe(dev, PTR_ERR(tsdata->gpio_reset), |
| "Failed to request RESET gpio\n"); |
| |
| tsdata->gpio_wake = devm_gpiod_get_optional(dev, "wake", |
| GPIOD_OUT_HIGH); |
| if (IS_ERR(tsdata->gpio_wake)) |
| return dev_err_probe(dev, PTR_ERR(tsdata->gpio_wake), |
| "Failed to get wake gpio\n"); |
| |
| tsdata->gpio_enable = devm_gpiod_get_optional(dev, "enable", |
| GPIOD_OUT_HIGH); |
| if (IS_ERR(tsdata->gpio_enable)) |
| return dev_err_probe(dev, PTR_ERR(tsdata->gpio_enable), |
| "Failed to get enable gpio\n"); |
| |
| if (tsdata->gpio_enable) |
| msleep(100); |
| |
| error = devm_request_threaded_irq(dev, client->irq, NULL, pixcir_ts_isr, |
| IRQF_TRIGGER_FALLING | IRQF_ONESHOT, |
| client->name, tsdata); |
| if (error) { |
| dev_err(dev, "failed to request irq %d\n", client->irq); |
| return error; |
| } |
| |
| pixcir_reset(tsdata); |
| |
| /* Always be in IDLE mode to save power, device supports auto wake */ |
| error = pixcir_set_power_mode(tsdata, PIXCIR_POWER_IDLE); |
| if (error) { |
| dev_err(dev, "Failed to set IDLE mode\n"); |
| return error; |
| } |
| |
| /* Stop device till opened */ |
| error = pixcir_stop(tsdata); |
| if (error) |
| return error; |
| |
| error = input_register_device(input); |
| if (error) |
| return error; |
| |
| i2c_set_clientdata(client, tsdata); |
| |
| return 0; |
| } |
| |
| static const struct pixcir_i2c_chip_data pixcir_ts_data = { |
| .max_fingers = 2, |
| /* no hw id support */ |
| }; |
| |
| static const struct pixcir_i2c_chip_data pixcir_tangoc_data = { |
| .max_fingers = 5, |
| .has_hw_ids = true, |
| }; |
| |
| static const struct i2c_device_id pixcir_i2c_ts_id[] = { |
| { "pixcir_ts", (unsigned long) &pixcir_ts_data }, |
| { "pixcir_tangoc", (unsigned long) &pixcir_tangoc_data }, |
| { } |
| }; |
| MODULE_DEVICE_TABLE(i2c, pixcir_i2c_ts_id); |
| |
| #ifdef CONFIG_OF |
| static const struct of_device_id pixcir_of_match[] = { |
| { .compatible = "pixcir,pixcir_ts", .data = &pixcir_ts_data }, |
| { .compatible = "pixcir,pixcir_tangoc", .data = &pixcir_tangoc_data }, |
| { } |
| }; |
| MODULE_DEVICE_TABLE(of, pixcir_of_match); |
| #endif |
| |
| static struct i2c_driver pixcir_i2c_ts_driver = { |
| .driver = { |
| .name = "pixcir_ts", |
| .pm = pm_sleep_ptr(&pixcir_dev_pm_ops), |
| .of_match_table = of_match_ptr(pixcir_of_match), |
| }, |
| .probe = pixcir_i2c_ts_probe, |
| .id_table = pixcir_i2c_ts_id, |
| }; |
| |
| module_i2c_driver(pixcir_i2c_ts_driver); |
| |
| MODULE_AUTHOR("Jianchun Bian <jcbian@pixcir.com.cn>, Dequan Meng <dqmeng@pixcir.com.cn>"); |
| MODULE_DESCRIPTION("Pixcir I2C Touchscreen Driver"); |
| MODULE_LICENSE("GPL"); |