diff options
Diffstat (limited to 'drivers/input/touchscreen/chipone_icn8318.c')
| -rw-r--r-- | drivers/input/touchscreen/chipone_icn8318.c | 271 |
1 files changed, 271 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/chipone_icn8318.c b/drivers/input/touchscreen/chipone_icn8318.c new file mode 100644 index 0000000000..d6876d10b2 --- /dev/null +++ b/drivers/input/touchscreen/chipone_icn8318.c @@ -0,0 +1,271 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Driver for ChipOne icn8318 i2c touchscreen controller + * + * Copyright (c) 2015 Red Hat Inc. + * + * Red Hat authors: + * 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> + +#define ICN8318_REG_POWER 4 +#define ICN8318_REG_TOUCHDATA 16 + +#define ICN8318_POWER_ACTIVE 0 +#define ICN8318_POWER_MONITOR 1 +#define ICN8318_POWER_HIBERNATE 2 + +#define ICN8318_MAX_TOUCHES 5 + +struct icn8318_touch { + __u8 slot; + __be16 x; + __be16 y; + __u8 pressure; /* Seems more like finger width then pressure really */ + __u8 event; +/* The difference between 2 and 3 is unclear */ +#define ICN8318_EVENT_NO_DATA 1 /* No finger seen yet since wakeup */ +#define ICN8318_EVENT_UPDATE1 2 /* New or updated coordinates */ +#define ICN8318_EVENT_UPDATE2 3 /* New or updated coordinates */ +#define ICN8318_EVENT_END 4 /* Finger lifted */ +} __packed; + +struct icn8318_touch_data { + __u8 softbutton; + __u8 touch_count; + struct icn8318_touch touches[ICN8318_MAX_TOUCHES]; +} __packed; + +struct icn8318_data { + struct i2c_client *client; + struct input_dev *input; + struct gpio_desc *wake_gpio; + struct touchscreen_properties prop; +}; + +static int icn8318_read_touch_data(struct i2c_client *client, + struct icn8318_touch_data *touch_data) +{ + u8 reg = ICN8318_REG_TOUCHDATA; + struct i2c_msg msg[2] = { + { + .addr = client->addr, + .len = 1, + .buf = ® + }, + { + .addr = client->addr, + .flags = I2C_M_RD, + .len = sizeof(struct icn8318_touch_data), + .buf = (u8 *)touch_data + } + }; + + return i2c_transfer(client->adapter, msg, 2); +} + +static inline bool icn8318_touch_active(u8 event) +{ + return (event == ICN8318_EVENT_UPDATE1) || + (event == ICN8318_EVENT_UPDATE2); +} + +static irqreturn_t icn8318_irq(int irq, void *dev_id) +{ + struct icn8318_data *data = dev_id; + struct device *dev = &data->client->dev; + struct icn8318_touch_data touch_data; + int i, ret; + + ret = icn8318_read_touch_data(data->client, &touch_data); + if (ret < 0) { + dev_err(dev, "Error reading touch data: %d\n", ret); + return IRQ_HANDLED; + } + + if (touch_data.softbutton) { + /* + * Other data is invalid when a softbutton is pressed. + * This needs some extra devicetree bindings to map the icn8318 + * softbutton codes to evdev codes. Currently no known devices + * use this. + */ + return IRQ_HANDLED; + } + + if (touch_data.touch_count > ICN8318_MAX_TOUCHES) { + dev_warn(dev, "Too much touches %d > %d\n", + touch_data.touch_count, ICN8318_MAX_TOUCHES); + touch_data.touch_count = ICN8318_MAX_TOUCHES; + } + + for (i = 0; i < touch_data.touch_count; i++) { + struct icn8318_touch *touch = &touch_data.touches[i]; + bool act = icn8318_touch_active(touch->event); + + input_mt_slot(data->input, touch->slot); + input_mt_report_slot_state(data->input, MT_TOOL_FINGER, act); + if (!act) + continue; + + touchscreen_report_pos(data->input, &data->prop, + be16_to_cpu(touch->x), + be16_to_cpu(touch->y), true); + } + + input_mt_sync_frame(data->input); + input_sync(data->input); + + return IRQ_HANDLED; +} + +static int icn8318_start(struct input_dev *dev) +{ + struct icn8318_data *data = input_get_drvdata(dev); + + enable_irq(data->client->irq); + gpiod_set_value_cansleep(data->wake_gpio, 1); + + return 0; +} + +static void icn8318_stop(struct input_dev *dev) +{ + struct icn8318_data *data = input_get_drvdata(dev); + + disable_irq(data->client->irq); + i2c_smbus_write_byte_data(data->client, ICN8318_REG_POWER, + ICN8318_POWER_HIBERNATE); + gpiod_set_value_cansleep(data->wake_gpio, 0); +} + +static int icn8318_suspend(struct device *dev) +{ + struct icn8318_data *data = i2c_get_clientdata(to_i2c_client(dev)); + + mutex_lock(&data->input->mutex); + if (input_device_enabled(data->input)) + icn8318_stop(data->input); + mutex_unlock(&data->input->mutex); + + return 0; +} + +static int icn8318_resume(struct device *dev) +{ + struct icn8318_data *data = i2c_get_clientdata(to_i2c_client(dev)); + + mutex_lock(&data->input->mutex); + if (input_device_enabled(data->input)) + icn8318_start(data->input); + mutex_unlock(&data->input->mutex); + + return 0; +} + +static DEFINE_SIMPLE_DEV_PM_OPS(icn8318_pm_ops, icn8318_suspend, icn8318_resume); + +static int icn8318_probe(struct i2c_client *client) +{ + struct device *dev = &client->dev; + struct icn8318_data *data; + struct input_dev *input; + int error; + + if (!client->irq) { + dev_err(dev, "Error no irq specified\n"); + return -EINVAL; + } + + data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->wake_gpio = devm_gpiod_get(dev, "wake", GPIOD_OUT_LOW); + if (IS_ERR(data->wake_gpio)) + return dev_err_probe(dev, PTR_ERR(data->wake_gpio), "Error getting wake gpio\n"); + + input = devm_input_allocate_device(dev); + if (!input) + return -ENOMEM; + + input->name = client->name; + input->id.bustype = BUS_I2C; + input->open = icn8318_start; + input->close = icn8318_stop; + input->dev.parent = dev; + + 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, &data->prop); + if (!input_abs_get_max(input, ABS_MT_POSITION_X) || + !input_abs_get_max(input, ABS_MT_POSITION_Y)) { + dev_err(dev, "Error touchscreen-size-x and/or -y missing\n"); + return -EINVAL; + } + + error = input_mt_init_slots(input, ICN8318_MAX_TOUCHES, + INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED); + if (error) + return error; + + data->client = client; + data->input = input; + input_set_drvdata(input, data); + + error = devm_request_threaded_irq(dev, client->irq, NULL, icn8318_irq, + IRQF_ONESHOT, client->name, data); + if (error) { + dev_err(dev, "Error requesting irq: %d\n", error); + return error; + } + + /* Stop device till opened */ + icn8318_stop(data->input); + + error = input_register_device(input); + if (error) + return error; + + i2c_set_clientdata(client, data); + + return 0; +} + +static const struct of_device_id icn8318_of_match[] = { + { .compatible = "chipone,icn8318" }, + { } +}; +MODULE_DEVICE_TABLE(of, icn8318_of_match); + +/* This is useless for OF-enabled devices, but it is needed by I2C subsystem */ +static const struct i2c_device_id icn8318_i2c_id[] = { + { }, +}; +MODULE_DEVICE_TABLE(i2c, icn8318_i2c_id); + +static struct i2c_driver icn8318_driver = { + .driver = { + .name = "chipone_icn8318", + .pm = pm_sleep_ptr(&icn8318_pm_ops), + .of_match_table = icn8318_of_match, + }, + .probe = icn8318_probe, + .id_table = icn8318_i2c_id, +}; + +module_i2c_driver(icn8318_driver); + +MODULE_DESCRIPTION("ChipOne icn8318 I2C Touchscreen Driver"); +MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>"); +MODULE_LICENSE("GPL"); |