| From 47f49370b3c1c7f4d4aae855966d2a3beef6c6d4 Mon Sep 17 00:00:00 2001 |
| From: Andrey Konovalov <andrey.konovalov@linaro.org> |
| Date: Fri, 12 Jun 2020 15:53:48 +0200 |
| Subject: [PATCH] media: i2c: imx290: fix reset GPIO pin handling |
| |
| Commit 3909a92d7df622b41b9ceeeea694e641cad7667b upstream. |
| |
| 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: Andrey Konovalov <andrey.konovalov@linaro.org> |
| Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> |
| Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> |
| Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> |
| --- |
| drivers/media/i2c/imx290.c | 7 ++++--- |
| 1 file changed, 4 insertions(+), 3 deletions(-) |
| |
| --- a/drivers/media/i2c/imx290.c |
| +++ b/drivers/media/i2c/imx290.c |
| @@ -628,7 +628,7 @@ static int imx290_power_on(struct device |
| } |
| |
| 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 devic |
| 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_clien |
| 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); |