diff options
Diffstat (limited to 'drivers/input/touchscreen/ektf2127.c')
| -rw-r--r-- | drivers/input/touchscreen/ektf2127.c | 362 |
1 files changed, 362 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/ektf2127.c b/drivers/input/touchscreen/ektf2127.c new file mode 100644 index 000000000..2d01a8cbf --- /dev/null +++ b/drivers/input/touchscreen/ektf2127.c @@ -0,0 +1,362 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Driver for ELAN eKTF2127 i2c touchscreen controller + * + * For this driver the layout of the Chipone icn8318 i2c + * touchscreencontroller is used. + * + * Author: + * Michel Verlaan <michel.verl@gmail.com> + * Siebren Vroegindeweij <siebren.vroegindeweij@hotmail.com> + * + * Original chipone_icn8318 driver: + * Hans de Goede <hdegoede@redhat.com> + */ + +#include <linux/gpio/consumer.h> +#include <linux/interrupt.h> +#include <linux/i2c.h> +#include <linux/input.h> +#include <linux/input/mt.h> +#include <linux/input/touchscreen.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/delay.h> + +/* Packet header defines (first byte of data send / received) */ +#define EKTF2127_NOISE 0x40 +#define EKTF2127_RESPONSE 0x52 +#define EKTF2127_REQUEST 0x53 +#define EKTF2127_HELLO 0x55 +#define EKTF2127_REPORT2 0x5a +#define EKTF2127_REPORT 0x5d +#define EKTF2127_CALIB_DONE 0x66 + +/* Register defines (second byte of data send / received) */ +#define EKTF2127_ENV_NOISY 0x41 +#define EKTF2127_HEIGHT 0x60 +#define EKTF2127_WIDTH 0x63 + +/* 2 bytes header + 5 * 3 bytes coordinates + 3 bytes pressure info + footer */ +#define EKTF2127_TOUCH_REPORT_SIZE 21 +#define EKTF2127_MAX_TOUCHES 5 + +struct ektf2127_ts { + struct i2c_client *client; + struct input_dev *input; + struct gpio_desc *power_gpios; + struct touchscreen_properties prop; +}; + +static void ektf2127_parse_coordinates(const u8 *buf, unsigned int touch_count, + struct input_mt_pos *touches) +{ + int index = 0; + int i; + + for (i = 0; i < touch_count; i++) { + index = 2 + i * 3; + + touches[i].x = (buf[index] & 0x0f); + touches[i].x <<= 8; + touches[i].x |= buf[index + 2]; + + touches[i].y = (buf[index] & 0xf0); + touches[i].y <<= 4; + touches[i].y |= buf[index + 1]; + } +} + +static void ektf2127_report_event(struct ektf2127_ts *ts, const u8 *buf) +{ + struct input_mt_pos touches[EKTF2127_MAX_TOUCHES]; + int slots[EKTF2127_MAX_TOUCHES]; + unsigned int touch_count, i; + + touch_count = buf[1] & 0x07; + if (touch_count > EKTF2127_MAX_TOUCHES) { + dev_err(&ts->client->dev, + "Too many touches %d > %d\n", + touch_count, EKTF2127_MAX_TOUCHES); + touch_count = EKTF2127_MAX_TOUCHES; + } + + ektf2127_parse_coordinates(buf, touch_count, touches); + input_mt_assign_slots(ts->input, slots, touches, + touch_count, 0); + + for (i = 0; i < touch_count; i++) { + input_mt_slot(ts->input, slots[i]); + input_mt_report_slot_state(ts->input, MT_TOOL_FINGER, true); + touchscreen_report_pos(ts->input, &ts->prop, + touches[i].x, touches[i].y, true); + } + + input_mt_sync_frame(ts->input); + input_sync(ts->input); +} + +static void ektf2127_report2_contact(struct ektf2127_ts *ts, int slot, + const u8 *buf, bool active) +{ + input_mt_slot(ts->input, slot); + input_mt_report_slot_state(ts->input, MT_TOOL_FINGER, active); + + if (active) { + int x = (buf[0] & 0xf0) << 4 | buf[1]; + int y = (buf[0] & 0x0f) << 8 | buf[2]; + + touchscreen_report_pos(ts->input, &ts->prop, x, y, true); + } +} + +static void ektf2127_report2_event(struct ektf2127_ts *ts, const u8 *buf) +{ + ektf2127_report2_contact(ts, 0, &buf[1], !!(buf[7] & 2)); + ektf2127_report2_contact(ts, 1, &buf[4], !!(buf[7] & 4)); + + input_mt_sync_frame(ts->input); + input_sync(ts->input); +} + +static irqreturn_t ektf2127_irq(int irq, void *dev_id) +{ + struct ektf2127_ts *ts = dev_id; + struct device *dev = &ts->client->dev; + char buf[EKTF2127_TOUCH_REPORT_SIZE]; + int ret; + + ret = i2c_master_recv(ts->client, buf, EKTF2127_TOUCH_REPORT_SIZE); + if (ret != EKTF2127_TOUCH_REPORT_SIZE) { + dev_err(dev, "Error reading touch data: %d\n", ret); + goto out; + } + + switch (buf[0]) { + case EKTF2127_REPORT: + ektf2127_report_event(ts, buf); + break; + + case EKTF2127_REPORT2: + ektf2127_report2_event(ts, buf); + break; + + case EKTF2127_NOISE: + if (buf[1] == EKTF2127_ENV_NOISY) + dev_dbg(dev, "Environment is electrically noisy\n"); + break; + + case EKTF2127_HELLO: + case EKTF2127_CALIB_DONE: + break; + + default: + dev_err(dev, "Unexpected packet header byte %#02x\n", buf[0]); + break; + } + +out: + return IRQ_HANDLED; +} + +static int ektf2127_start(struct input_dev *dev) +{ + struct ektf2127_ts *ts = input_get_drvdata(dev); + + enable_irq(ts->client->irq); + gpiod_set_value_cansleep(ts->power_gpios, 1); + + return 0; +} + +static void ektf2127_stop(struct input_dev *dev) +{ + struct ektf2127_ts *ts = input_get_drvdata(dev); + + disable_irq(ts->client->irq); + gpiod_set_value_cansleep(ts->power_gpios, 0); +} + +static int __maybe_unused ektf2127_suspend(struct device *dev) +{ + struct ektf2127_ts *ts = i2c_get_clientdata(to_i2c_client(dev)); + + mutex_lock(&ts->input->mutex); + if (input_device_enabled(ts->input)) + ektf2127_stop(ts->input); + mutex_unlock(&ts->input->mutex); + + return 0; +} + +static int __maybe_unused ektf2127_resume(struct device *dev) +{ + struct ektf2127_ts *ts = i2c_get_clientdata(to_i2c_client(dev)); + + mutex_lock(&ts->input->mutex); + if (input_device_enabled(ts->input)) + ektf2127_start(ts->input); + mutex_unlock(&ts->input->mutex); + + return 0; +} + +static SIMPLE_DEV_PM_OPS(ektf2127_pm_ops, ektf2127_suspend, + ektf2127_resume); + +static int ektf2127_query_dimension(struct i2c_client *client, bool width) +{ + struct device *dev = &client->dev; + const char *what = width ? "width" : "height"; + u8 what_code = width ? EKTF2127_WIDTH : EKTF2127_HEIGHT; + u8 buf[4]; + int ret; + int error; + + /* Request dimension */ + buf[0] = EKTF2127_REQUEST; + buf[1] = width ? EKTF2127_WIDTH : EKTF2127_HEIGHT; + buf[2] = 0x00; + buf[3] = 0x00; + ret = i2c_master_send(client, buf, sizeof(buf)); + if (ret != sizeof(buf)) { + error = ret < 0 ? ret : -EIO; + dev_err(dev, "Failed to request %s: %d\n", what, error); + return error; + } + + msleep(20); + + /* Read response */ + ret = i2c_master_recv(client, buf, sizeof(buf)); + if (ret != sizeof(buf)) { + error = ret < 0 ? ret : -EIO; + dev_err(dev, "Failed to receive %s data: %d\n", what, error); + return error; + } + + if (buf[0] != EKTF2127_RESPONSE || buf[1] != what_code) { + dev_err(dev, "Unexpected %s data: %#02x %#02x\n", + what, buf[0], buf[1]); + return -EIO; + } + + return (((buf[3] & 0xf0) << 4) | buf[2]) - 1; +} + +static int ektf2127_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct device *dev = &client->dev; + struct ektf2127_ts *ts; + struct input_dev *input; + u8 buf[4]; + int max_x, max_y; + int error; + + if (!client->irq) { + dev_err(dev, "Error no irq specified\n"); + return -EINVAL; + } + + ts = devm_kzalloc(dev, sizeof(*ts), GFP_KERNEL); + if (!ts) + return -ENOMEM; + + /* This requests the gpio *and* turns on the touchscreen controller */ + ts->power_gpios = devm_gpiod_get(dev, "power", GPIOD_OUT_HIGH); + if (IS_ERR(ts->power_gpios)) { + error = PTR_ERR(ts->power_gpios); + if (error != -EPROBE_DEFER) + dev_err(dev, "Error getting power gpio: %d\n", error); + return error; + } + + input = devm_input_allocate_device(dev); + if (!input) + return -ENOMEM; + + input->name = client->name; + input->id.bustype = BUS_I2C; + input->open = ektf2127_start; + input->close = ektf2127_stop; + + ts->client = client; + + /* Read hello (ignore result, depends on initial power state) */ + msleep(20); + i2c_master_recv(ts->client, buf, sizeof(buf)); + + /* Read resolution from chip */ + max_x = ektf2127_query_dimension(client, true); + if (max_x < 0) + return max_x; + + max_y = ektf2127_query_dimension(client, false); + if (max_y < 0) + return max_y; + + input_set_abs_params(input, ABS_MT_POSITION_X, 0, max_x, 0, 0); + input_set_abs_params(input, ABS_MT_POSITION_Y, 0, max_y, 0, 0); + touchscreen_parse_properties(input, true, &ts->prop); + + error = input_mt_init_slots(input, EKTF2127_MAX_TOUCHES, + INPUT_MT_DIRECT | + INPUT_MT_DROP_UNUSED | + INPUT_MT_TRACK); + if (error) + return error; + + ts->input = input; + input_set_drvdata(input, ts); + + error = devm_request_threaded_irq(dev, client->irq, + NULL, ektf2127_irq, + IRQF_ONESHOT, client->name, ts); + if (error) { + dev_err(dev, "Error requesting irq: %d\n", error); + return error; + } + + /* Stop device till opened */ + ektf2127_stop(ts->input); + + error = input_register_device(input); + if (error) + return error; + + i2c_set_clientdata(client, ts); + + return 0; +} + +#ifdef CONFIG_OF +static const struct of_device_id ektf2127_of_match[] = { + { .compatible = "elan,ektf2127" }, + { .compatible = "elan,ektf2132" }, + {} +}; +MODULE_DEVICE_TABLE(of, ektf2127_of_match); +#endif + +static const struct i2c_device_id ektf2127_i2c_id[] = { + { "ektf2127", 0 }, + { "ektf2132", 0 }, + {} +}; +MODULE_DEVICE_TABLE(i2c, ektf2127_i2c_id); + +static struct i2c_driver ektf2127_driver = { + .driver = { + .name = "elan_ektf2127", + .pm = &ektf2127_pm_ops, + .of_match_table = of_match_ptr(ektf2127_of_match), + }, + .probe = ektf2127_probe, + .id_table = ektf2127_i2c_id, +}; +module_i2c_driver(ektf2127_driver); + +MODULE_DESCRIPTION("ELAN eKTF2127/eKTF2132 I2C Touchscreen Driver"); +MODULE_AUTHOR("Michel Verlaan, Siebren Vroegindeweij"); +MODULE_LICENSE("GPL"); |