| // SPDX-License-Identifier: GPL-2.0-only |
| |
| #include <linux/bits.h> |
| #include <linux/delay.h> |
| #include <linux/i2c.h> |
| #include <linux/input.h> |
| #include <linux/input/mt.h> |
| #include <linux/input/touchscreen.h> |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/property.h> |
| #include <linux/regulator/consumer.h> |
| |
| #define IST3038C_HIB_ACCESS (0x800B << 16) |
| #define IST3038C_DIRECT_ACCESS BIT(31) |
| #define IST3038C_REG_CHIPID 0x40001000 |
| #define IST3038C_REG_HIB_BASE 0x30000100 |
| #define IST3038C_REG_TOUCH_STATUS (IST3038C_REG_HIB_BASE | IST3038C_HIB_ACCESS) |
| #define IST3038C_REG_TOUCH_COORD (IST3038C_REG_HIB_BASE | IST3038C_HIB_ACCESS | 0x8) |
| #define IST3038C_REG_INTR_MESSAGE (IST3038C_REG_HIB_BASE | IST3038C_HIB_ACCESS | 0x4) |
| #define IST3038C_WHOAMI 0x38c |
| #define IST3038C_CHIP_ON_DELAY_MS 60 |
| #define IST3038C_I2C_RETRY_COUNT 3 |
| #define IST3038C_MAX_FINGER_NUM 10 |
| #define IST3038C_X_MASK GENMASK(23, 12) |
| #define IST3038C_X_SHIFT 12 |
| #define IST3038C_Y_MASK GENMASK(11, 0) |
| #define IST3038C_AREA_MASK GENMASK(27, 24) |
| #define IST3038C_AREA_SHIFT 24 |
| #define IST3038C_FINGER_COUNT_MASK GENMASK(15, 12) |
| #define IST3038C_FINGER_COUNT_SHIFT 12 |
| #define IST3038C_FINGER_STATUS_MASK GENMASK(9, 0) |
| |
| struct imagis_ts { |
| struct i2c_client *client; |
| struct input_dev *input_dev; |
| struct touchscreen_properties prop; |
| struct regulator_bulk_data supplies[2]; |
| }; |
| |
| static int imagis_i2c_read_reg(struct imagis_ts *ts, |
| unsigned int reg, u32 *data) |
| { |
| __be32 ret_be; |
| __be32 reg_be = cpu_to_be32(reg); |
| struct i2c_msg msg[] = { |
| { |
| .addr = ts->client->addr, |
| .flags = 0, |
| .buf = (unsigned char *)®_be, |
| .len = sizeof(reg_be), |
| }, { |
| .addr = ts->client->addr, |
| .flags = I2C_M_RD, |
| .buf = (unsigned char *)&ret_be, |
| .len = sizeof(ret_be), |
| }, |
| }; |
| int ret, error; |
| int retry = IST3038C_I2C_RETRY_COUNT; |
| |
| /* Retry in case the controller fails to respond */ |
| do { |
| ret = i2c_transfer(ts->client->adapter, msg, ARRAY_SIZE(msg)); |
| if (ret == ARRAY_SIZE(msg)) { |
| *data = be32_to_cpu(ret_be); |
| return 0; |
| } |
| |
| error = ret < 0 ? ret : -EIO; |
| dev_err(&ts->client->dev, |
| "%s - i2c_transfer failed: %d (%d)\n", |
| __func__, error, ret); |
| } while (--retry); |
| |
| return error; |
| } |
| |
| static irqreturn_t imagis_interrupt(int irq, void *dev_id) |
| { |
| struct imagis_ts *ts = dev_id; |
| u32 intr_message, finger_status; |
| unsigned int finger_count, finger_pressed; |
| int i; |
| int error; |
| |
| error = imagis_i2c_read_reg(ts, IST3038C_REG_INTR_MESSAGE, |
| &intr_message); |
| if (error) { |
| dev_err(&ts->client->dev, |
| "failed to read the interrupt message: %d\n", error); |
| goto out; |
| } |
| |
| finger_count = (intr_message & IST3038C_FINGER_COUNT_MASK) >> |
| IST3038C_FINGER_COUNT_SHIFT; |
| if (finger_count > IST3038C_MAX_FINGER_NUM) { |
| dev_err(&ts->client->dev, |
| "finger count %d is more than maximum supported\n", |
| finger_count); |
| goto out; |
| } |
| |
| finger_pressed = intr_message & IST3038C_FINGER_STATUS_MASK; |
| |
| for (i = 0; i < finger_count; i++) { |
| error = imagis_i2c_read_reg(ts, |
| IST3038C_REG_TOUCH_COORD + (i * 4), |
| &finger_status); |
| if (error) { |
| dev_err(&ts->client->dev, |
| "failed to read coordinates for finger %d: %d\n", |
| i, error); |
| goto out; |
| } |
| |
| input_mt_slot(ts->input_dev, i); |
| input_mt_report_slot_state(ts->input_dev, MT_TOOL_FINGER, |
| finger_pressed & BIT(i)); |
| touchscreen_report_pos(ts->input_dev, &ts->prop, |
| (finger_status & IST3038C_X_MASK) >> |
| IST3038C_X_SHIFT, |
| finger_status & IST3038C_Y_MASK, 1); |
| input_report_abs(ts->input_dev, ABS_MT_TOUCH_MAJOR, |
| (finger_status & IST3038C_AREA_MASK) >> |
| IST3038C_AREA_SHIFT); |
| } |
| |
| input_mt_sync_frame(ts->input_dev); |
| input_sync(ts->input_dev); |
| |
| out: |
| return IRQ_HANDLED; |
| } |
| |
| static void imagis_power_off(void *_ts) |
| { |
| struct imagis_ts *ts = _ts; |
| |
| regulator_bulk_disable(ARRAY_SIZE(ts->supplies), ts->supplies); |
| } |
| |
| static int imagis_power_on(struct imagis_ts *ts) |
| { |
| int error; |
| |
| error = regulator_bulk_enable(ARRAY_SIZE(ts->supplies), ts->supplies); |
| if (error) |
| return error; |
| |
| msleep(IST3038C_CHIP_ON_DELAY_MS); |
| |
| return 0; |
| } |
| |
| static int imagis_start(struct imagis_ts *ts) |
| { |
| int error; |
| |
| error = imagis_power_on(ts); |
| if (error) |
| return error; |
| |
| enable_irq(ts->client->irq); |
| |
| return 0; |
| } |
| |
| static int imagis_stop(struct imagis_ts *ts) |
| { |
| disable_irq(ts->client->irq); |
| |
| imagis_power_off(ts); |
| |
| return 0; |
| } |
| |
| static int imagis_input_open(struct input_dev *dev) |
| { |
| struct imagis_ts *ts = input_get_drvdata(dev); |
| |
| return imagis_start(ts); |
| } |
| |
| static void imagis_input_close(struct input_dev *dev) |
| { |
| struct imagis_ts *ts = input_get_drvdata(dev); |
| |
| imagis_stop(ts); |
| } |
| |
| static int imagis_init_input_dev(struct imagis_ts *ts) |
| { |
| struct input_dev *input_dev; |
| int error; |
| |
| input_dev = devm_input_allocate_device(&ts->client->dev); |
| if (!input_dev) |
| return -ENOMEM; |
| |
| ts->input_dev = input_dev; |
| |
| input_dev->name = "Imagis capacitive touchscreen"; |
| input_dev->phys = "input/ts"; |
| input_dev->id.bustype = BUS_I2C; |
| input_dev->open = imagis_input_open; |
| input_dev->close = imagis_input_close; |
| |
| input_set_drvdata(input_dev, ts); |
| |
| input_set_capability(input_dev, EV_ABS, ABS_MT_POSITION_X); |
| input_set_capability(input_dev, EV_ABS, ABS_MT_POSITION_Y); |
| input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0); |
| |
| touchscreen_parse_properties(input_dev, true, &ts->prop); |
| if (!ts->prop.max_x || !ts->prop.max_y) { |
| dev_err(&ts->client->dev, |
| "Touchscreen-size-x and/or touchscreen-size-y not set in dts\n"); |
| return -EINVAL; |
| } |
| |
| error = input_mt_init_slots(input_dev, |
| IST3038C_MAX_FINGER_NUM, |
| INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED); |
| if (error) { |
| dev_err(&ts->client->dev, |
| "Failed to initialize MT slots: %d", error); |
| return error; |
| } |
| |
| error = input_register_device(input_dev); |
| if (error) { |
| dev_err(&ts->client->dev, |
| "Failed to register input device: %d", error); |
| return error; |
| } |
| |
| return 0; |
| } |
| |
| static int imagis_init_regulators(struct imagis_ts *ts) |
| { |
| struct i2c_client *client = ts->client; |
| |
| ts->supplies[0].supply = "vdd"; |
| ts->supplies[1].supply = "vddio"; |
| return devm_regulator_bulk_get(&client->dev, |
| ARRAY_SIZE(ts->supplies), |
| ts->supplies); |
| } |
| |
| static int imagis_probe(struct i2c_client *i2c) |
| { |
| struct device *dev = &i2c->dev; |
| struct imagis_ts *ts; |
| int chip_id, error; |
| |
| ts = devm_kzalloc(dev, sizeof(*ts), GFP_KERNEL); |
| if (!ts) |
| return -ENOMEM; |
| |
| ts->client = i2c; |
| |
| error = imagis_init_regulators(ts); |
| if (error) { |
| dev_err(dev, "regulator init error: %d\n", error); |
| return error; |
| } |
| |
| error = imagis_power_on(ts); |
| if (error) { |
| dev_err(dev, "failed to enable regulators: %d\n", error); |
| return error; |
| } |
| |
| error = devm_add_action_or_reset(dev, imagis_power_off, ts); |
| if (error) { |
| dev_err(dev, "failed to install poweroff action: %d\n", error); |
| return error; |
| } |
| |
| error = imagis_i2c_read_reg(ts, |
| IST3038C_REG_CHIPID | IST3038C_DIRECT_ACCESS, |
| &chip_id); |
| if (error) { |
| dev_err(dev, "chip ID read failure: %d\n", error); |
| return error; |
| } |
| |
| if (chip_id != IST3038C_WHOAMI) { |
| dev_err(dev, "unknown chip ID: 0x%x\n", chip_id); |
| return -EINVAL; |
| } |
| |
| error = devm_request_threaded_irq(dev, i2c->irq, |
| NULL, imagis_interrupt, |
| IRQF_ONESHOT | IRQF_NO_AUTOEN, |
| "imagis-touchscreen", ts); |
| if (error) { |
| dev_err(dev, "IRQ %d allocation failure: %d\n", |
| i2c->irq, error); |
| return error; |
| } |
| |
| error = imagis_init_input_dev(ts); |
| if (error) |
| return error; |
| |
| return 0; |
| } |
| |
| static int imagis_suspend(struct device *dev) |
| { |
| struct i2c_client *client = to_i2c_client(dev); |
| struct imagis_ts *ts = i2c_get_clientdata(client); |
| int retval = 0; |
| |
| mutex_lock(&ts->input_dev->mutex); |
| |
| if (input_device_enabled(ts->input_dev)) |
| retval = imagis_stop(ts); |
| |
| mutex_unlock(&ts->input_dev->mutex); |
| |
| return retval; |
| } |
| |
| static int imagis_resume(struct device *dev) |
| { |
| struct i2c_client *client = to_i2c_client(dev); |
| struct imagis_ts *ts = i2c_get_clientdata(client); |
| int retval = 0; |
| |
| mutex_lock(&ts->input_dev->mutex); |
| |
| if (input_device_enabled(ts->input_dev)) |
| retval = imagis_start(ts); |
| |
| mutex_unlock(&ts->input_dev->mutex); |
| |
| return retval; |
| } |
| |
| static DEFINE_SIMPLE_DEV_PM_OPS(imagis_pm_ops, imagis_suspend, imagis_resume); |
| |
| #ifdef CONFIG_OF |
| static const struct of_device_id imagis_of_match[] = { |
| { .compatible = "imagis,ist3038c", }, |
| { }, |
| }; |
| MODULE_DEVICE_TABLE(of, imagis_of_match); |
| #endif |
| |
| static struct i2c_driver imagis_ts_driver = { |
| .driver = { |
| .name = "imagis-touchscreen", |
| .pm = pm_sleep_ptr(&imagis_pm_ops), |
| .of_match_table = of_match_ptr(imagis_of_match), |
| }, |
| .probe_new = imagis_probe, |
| }; |
| |
| module_i2c_driver(imagis_ts_driver); |
| |
| MODULE_DESCRIPTION("Imagis IST3038C Touchscreen Driver"); |
| MODULE_AUTHOR("Markuss Broks <markuss.broks@gmail.com>"); |
| MODULE_LICENSE("GPL"); |