[PATCHv2 2/2] Input: atmel_mxt_ts: Add support for reset line
From: Sebastian Reichel <hidden>
Date: 2017-07-03 12:39:06
Also in:
linux-devicetree, lkml
Subsystem:
atmel maxtouch driver, input (keyboard, mouse, joystick, touchscreen) drivers, open firmware and flattened device tree bindings, the rest · Maintainers:
Nick Dyer, Dmitry Torokhov, Rob Herring, Krzysztof Kozlowski, Conor Dooley, Linus Torvalds
Provide support for controlling reset pin. If this is not driven correctly the device will be held in reset and will not respond. Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Sebastian Reichel <redacted> --- .../devicetree/bindings/input/atmel,maxtouch.txt | 2 ++ drivers/input/touchscreen/atmel_mxt_ts.c | 22 ++++++++++++++++++++++ 2 files changed, 24 insertions(+)
diff --git a/Documentation/devicetree/bindings/input/atmel,maxtouch.txt b/Documentation/devicetree/bindings/input/atmel,maxtouch.txt
index 1852906517ab..23e3abc3fdef 100644
--- a/Documentation/devicetree/bindings/input/atmel,maxtouch.txt
+++ b/Documentation/devicetree/bindings/input/atmel,maxtouch.txt@@ -22,6 +22,8 @@ Optional properties for main touchpad device: experiment to determine which bit corresponds to which input. Use KEY_RESERVED for unused padding values. +- reset-gpios: GPIO specifier for the touchscreen's reset pin (active low) + Example: touch@4b {
diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
index 9a7b8eba64a6..599f92363188 100644
--- a/drivers/input/touchscreen/atmel_mxt_ts.c
+++ b/drivers/input/touchscreen/atmel_mxt_ts.c@@ -28,6 +28,7 @@ #include <linux/interrupt.h> #include <linux/of.h> #include <linux/slab.h> +#include <linux/gpio/consumer.h> #include <asm/unaligned.h> #include <media/v4l2-device.h> #include <media/v4l2-ioctl.h>
@@ -300,6 +301,7 @@ struct mxt_data { u8 multitouch; struct t7_config t7_cfg; struct mxt_dbg dbg; + struct gpio_desc *reset_gpio; /* Cached parameters from object table */ u16 T5_address;
@@ -3133,6 +3135,14 @@ static int mxt_probe(struct i2c_client *client, const struct i2c_device_id *id) init_completion(&data->reset_completion); init_completion(&data->crc_completion); + data->reset_gpio = devm_gpiod_get_optional(&client->dev, "reset", + GPIOD_OUT_LOW); + if (IS_ERR(data->reset_gpio)) { + error = PTR_ERR(data->reset_gpio); + dev_err(&client->dev, "Failed to get reset gpio: %d\n", error); + return error; + } + error = devm_request_threaded_irq(&client->dev, client->irq, NULL, mxt_interrupt, pdata->irqflags | IRQF_ONESHOT,
@@ -3142,6 +3152,18 @@ static int mxt_probe(struct i2c_client *client, const struct i2c_device_id *id) return error; } + if (data->reset_gpio) { + data->in_bootloader = true; + msleep(MXT_RESET_TIME); + reinit_completion(&data->bl_completion); + gpiod_set_value(data->reset_gpio, 1); + error = mxt_wait_for_completion(data, &data->bl_completion, + MXT_RESET_TIMEOUT); + if (error) + return error; + data->in_bootloader = false; + } + disable_irq(client->irq); error = mxt_initialize(data);
--
2.13.2