diff options
Diffstat (limited to 'drivers/input/touchscreen/ar1021_i2c.c')
| -rw-r--r-- | drivers/input/touchscreen/ar1021_i2c.c | 195 |
1 files changed, 195 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/ar1021_i2c.c b/drivers/input/touchscreen/ar1021_i2c.c new file mode 100644 index 000000000..c0d5c2413 --- /dev/null +++ b/drivers/input/touchscreen/ar1021_i2c.c @@ -0,0 +1,195 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Microchip AR1020 and AR1021 driver for I2C + * + * Author: Christian Gmeiner <christian.gmeiner@gmail.com> + */ + +#include <linux/bitops.h> +#include <linux/module.h> +#include <linux/input.h> +#include <linux/of.h> +#include <linux/i2c.h> +#include <linux/irq.h> +#include <linux/interrupt.h> + +#define AR1021_TOUCH_PKG_SIZE 5 + +#define AR1021_MAX_X 4095 +#define AR1021_MAX_Y 4095 + +#define AR1021_CMD 0x55 + +#define AR1021_CMD_ENABLE_TOUCH 0x12 + +struct ar1021_i2c { + struct i2c_client *client; + struct input_dev *input; + u8 data[AR1021_TOUCH_PKG_SIZE]; +}; + +static irqreturn_t ar1021_i2c_irq(int irq, void *dev_id) +{ + struct ar1021_i2c *ar1021 = dev_id; + struct input_dev *input = ar1021->input; + u8 *data = ar1021->data; + unsigned int x, y, button; + int retval; + + retval = i2c_master_recv(ar1021->client, + ar1021->data, sizeof(ar1021->data)); + if (retval != sizeof(ar1021->data)) + goto out; + + /* sync bit set ? */ + if (!(data[0] & BIT(7))) + goto out; + + button = data[0] & BIT(0); + x = ((data[2] & 0x1f) << 7) | (data[1] & 0x7f); + y = ((data[4] & 0x1f) << 7) | (data[3] & 0x7f); + + input_report_abs(input, ABS_X, x); + input_report_abs(input, ABS_Y, y); + input_report_key(input, BTN_TOUCH, button); + input_sync(input); + +out: + return IRQ_HANDLED; +} + +static int ar1021_i2c_open(struct input_dev *dev) +{ + static const u8 cmd_enable_touch[] = { + AR1021_CMD, + 0x01, /* number of bytes after this */ + AR1021_CMD_ENABLE_TOUCH + }; + struct ar1021_i2c *ar1021 = input_get_drvdata(dev); + struct i2c_client *client = ar1021->client; + int error; + + error = i2c_master_send(ar1021->client, cmd_enable_touch, + sizeof(cmd_enable_touch)); + if (error < 0) + return error; + + enable_irq(client->irq); + + return 0; +} + +static void ar1021_i2c_close(struct input_dev *dev) +{ + struct ar1021_i2c *ar1021 = input_get_drvdata(dev); + struct i2c_client *client = ar1021->client; + + disable_irq(client->irq); +} + +static int ar1021_i2c_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct ar1021_i2c *ar1021; + struct input_dev *input; + int error; + + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { + dev_err(&client->dev, "i2c_check_functionality error\n"); + return -ENXIO; + } + + ar1021 = devm_kzalloc(&client->dev, sizeof(*ar1021), GFP_KERNEL); + if (!ar1021) + return -ENOMEM; + + input = devm_input_allocate_device(&client->dev); + if (!input) + return -ENOMEM; + + ar1021->client = client; + ar1021->input = input; + + input->name = "ar1021 I2C Touchscreen"; + input->id.bustype = BUS_I2C; + input->dev.parent = &client->dev; + input->open = ar1021_i2c_open; + input->close = ar1021_i2c_close; + + __set_bit(INPUT_PROP_DIRECT, input->propbit); + input_set_capability(input, EV_KEY, BTN_TOUCH); + input_set_abs_params(input, ABS_X, 0, AR1021_MAX_X, 0, 0); + input_set_abs_params(input, ABS_Y, 0, AR1021_MAX_Y, 0, 0); + + input_set_drvdata(input, ar1021); + + error = devm_request_threaded_irq(&client->dev, client->irq, + NULL, ar1021_i2c_irq, + IRQF_ONESHOT, + "ar1021_i2c", ar1021); + if (error) { + dev_err(&client->dev, + "Failed to enable IRQ, error: %d\n", error); + return error; + } + + /* Disable the IRQ, we'll enable it in ar1021_i2c_open() */ + disable_irq(client->irq); + + error = input_register_device(ar1021->input); + if (error) { + dev_err(&client->dev, + "Failed to register input device, error: %d\n", error); + return error; + } + + return 0; +} + +static int __maybe_unused ar1021_i2c_suspend(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + + disable_irq(client->irq); + + return 0; +} + +static int __maybe_unused ar1021_i2c_resume(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + + enable_irq(client->irq); + + return 0; +} + +static SIMPLE_DEV_PM_OPS(ar1021_i2c_pm, ar1021_i2c_suspend, ar1021_i2c_resume); + +static const struct i2c_device_id ar1021_i2c_id[] = { + { "ar1021", 0 }, + { }, +}; +MODULE_DEVICE_TABLE(i2c, ar1021_i2c_id); + +static const struct of_device_id ar1021_i2c_of_match[] = { + { .compatible = "microchip,ar1021-i2c", }, + { } +}; +MODULE_DEVICE_TABLE(of, ar1021_i2c_of_match); + +static struct i2c_driver ar1021_i2c_driver = { + .driver = { + .name = "ar1021_i2c", + .pm = &ar1021_i2c_pm, + .of_match_table = ar1021_i2c_of_match, + }, + + .probe = ar1021_i2c_probe, + .id_table = ar1021_i2c_id, +}; +module_i2c_driver(ar1021_i2c_driver); + +MODULE_AUTHOR("Christian Gmeiner <christian.gmeiner@gmail.com>"); +MODULE_DESCRIPTION("Microchip AR1020 and AR1021 I2C Driver"); +MODULE_LICENSE("GPL"); |