On 30.05.21 22:44, Fabio Estevam wrote:
> On a design where the ADV7180 pin is pulled down, it is not possible
> to make it functional unless the GPIO connected to this pin goes
> high.
>
> Add support for the reset GPIO by introducing an optional property
> called 'reset-gpios'.
>
> Note: the reset operation is still performed via software as recommended
> by the Analog Devices, but the reset GPIO still needs to go high to make
> the chip operational.
>
> Signed-off-by: Fabio Estevam <festevam@xxxxxxxxx>
> ---
> drivers/media/i2c/adv7180.c | 14 +++++++++++++-
> 1 file changed, 13 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/media/i2c/adv7180.c b/drivers/media/i2c/adv7180.c
> index 44bb6fe85644..2811f2c337fa 100644
> --- a/drivers/media/i2c/adv7180.c
> +++ b/drivers/media/i2c/adv7180.c
> @@ -205,6 +205,7 @@ struct adv7180_state {
> struct mutex mutex; /* mutual excl. when accessing chip */
> int irq;
> struct gpio_desc *pwdn_gpio;
> + struct gpio_desc *reset_gpio;
> v4l2_std_id curr_norm;
> bool powered;
> bool streaming;
> @@ -473,13 +474,15 @@ static int adv7180_g_frame_interval(struct v4l2_subdev *sd,
>
> static void adv7180_set_power_pin(struct adv7180_state *state, bool on)
> {
> - if (!state->pwdn_gpio)
> + if (!state->pwdn_gpio && !state->reset_gpio)
> return;
>
> if (on) {
> + gpiod_set_value_cansleep(state->reset_gpio, 0);
> gpiod_set_value_cansleep(state->pwdn_gpio, 0);
The datasheet specifies a delay of 5 ms between deasserting the PWRDWN and the RESET GPIO. Also this function is named adv7180_set_power_pin() which doesn't fit anymore if we also handle the RESET GPIO here.
As I was recently working with the ADV7280-M, I came up with a similar patch: https://git.kontron-electronics.de/linux/linux/-/commit/3619ed166140a0499ada7b14e5f1846a0ed7d18d.
What do you think?
> usleep_range(5000, 10000);
> } else {
> + gpiod_set_value_cansleep(state->reset_gpio, 1);
> gpiod_set_value_cansleep(state->pwdn_gpio, 1);
> }
> }
> @@ -1338,6 +1341,15 @@ static int adv7180_probe(struct i2c_client *client,
> return ret;
> }
>
> + state->reset_gpio = devm_gpiod_get_optional(&client->dev, "reset",
> + GPIOD_OUT_HIGH);
> + if (IS_ERR(state->reset_gpio)) {
> + ret = PTR_ERR(state->reset_gpio);
> + v4l_err(client, "request for reset pin failed: %d\n", ret);
> + return ret;
> + }
> +
> +
> if (state->chip_info->flags & ADV7180_FLAG_MIPI_CSI2) {
> state->csi_client = i2c_new_dummy_device(client->adapter,
> ADV7180_DEFAULT_CSI_I2C_ADDR);
>
