diff options
Diffstat (limited to 'drivers/input/touchscreen/imagis.c')
-rw-r--r-- | drivers/input/touchscreen/imagis.c | 367 |
1 files changed, 367 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/imagis.c b/drivers/input/touchscreen/imagis.c new file mode 100644 index 000000000..e2697e6c6 --- /dev/null +++ b/drivers/input/touchscreen/imagis.c @@ -0,0 +1,367 @@ +// 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 __maybe_unused 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 __maybe_unused 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 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 = &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"); |