Commit 3909a92d authored by Andrey Konovalov's avatar Andrey Konovalov Committed by Mauro Carvalho Chehab
Browse files

media: i2c: imx290: fix reset GPIO pin handling 

According to https://www.kernel.org/doc/Documentation/gpio/consumer.txt

,

- all of the gpiod_set_value_xxx() functions operate with the *logical*
value. So in imx290_power_on() the reset signal should be cleared
(de-asserted) with gpiod_set_value_cansleep(imx290->rst_gpio, 0), and in
imx290_power_off() the value of 1 must be used to apply/assert the reset
to the sensor. In the device tree the reset pin is described as
GPIO_ACTIVE_LOW, and gpiod_set_value_xxx() functions take this into
account,

- when devm_gpiod_get_optional() is called with GPIOD_ASIS, the GPIO is
not initialized, and the direction must be set later; using a GPIO
without setting its direction first is illegal and will result in undefined
behavior. Fix this by using GPIOD_OUT_HIGH instead of GPIOD_ASIS (this
asserts the reset signal to the sensor initially).

Signed-off-by: default avatarAndrey Konovalov <andrey.konovalov@linaro.org>
Reviewed-by: default avatarManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: default avatarSakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab+huawei@kernel.org>
parent 8d2d1bed

drivers/media/i2c/imx290.c

+4 −3
Original line number Diff line number Diff line
@@ -628,7 +628,7 @@ static int imx290_power_on(struct device *dev) 
	}



	usleep_range(1, 2);

	gpiod_set_value_cansleep(imx290->rst_gpio, 1);

	gpiod_set_value_cansleep(imx290->rst_gpio, 0);

	usleep_range(30000, 31000);



	return 0;
@@ -641,7 +641,7 @@ static int imx290_power_off(struct device *dev) 
	struct imx290 *imx290 = to_imx290(sd);



	clk_disable_unprepare(imx290->xclk);

	gpiod_set_value_cansleep(imx290->rst_gpio, 0);

	gpiod_set_value_cansleep(imx290->rst_gpio, 1);

	regulator_bulk_disable(IMX290_NUM_SUPPLIES, imx290->supplies);



	return 0;
@@ -757,7 +757,8 @@ static int imx290_probe(struct i2c_client *client) 
		goto free_err;

	}



	imx290->rst_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_ASIS);

	imx290->rst_gpio = devm_gpiod_get_optional(dev, "reset",

						   GPIOD_OUT_HIGH);

	if (IS_ERR(imx290->rst_gpio)) {

		dev_err(dev, "Cannot get reset gpio\n");

		ret = PTR_ERR(imx290->rst_gpio);