Re: [PATCH 3/4] media: ov2740: Add powerdown GPIO support

[Stanislaw Gruszka <stanislaw.gruszka@linux.intel.com>]

On Thu, Nov 28, 2024 at 04:23:37PM +0100, Hans de Goede wrote:
> The ov2740 sensor has both reset and power_down inputs according to
> the datasheet one or the other should always be tied to DOVDD but on
> some designs both are attached to GPIOs.
> 
> Add support for controlling both a reset and a powerdown GPIO.
> 
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Tested-by: Stanislaw Gruszka <stanislaw.gruszka@linux.intel.com>
> ---
>  drivers/media/i2c/ov2740.c | 15 +++++++++++++--
>  1 file changed, 13 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/media/i2c/ov2740.c b/drivers/media/i2c/ov2740.c
> index 998e1977978d..14d0a0588cc2 100644
> --- a/drivers/media/i2c/ov2740.c
> +++ b/drivers/media/i2c/ov2740.c
> @@ -525,6 +525,7 @@ struct ov2740 {
>  
>  	/* GPIOs, clocks */
>  	struct gpio_desc *reset_gpio;
> +	struct gpio_desc *powerdown_gpio;
>  	struct clk *clk;
>  
>  	/* Current mode */
> @@ -1306,6 +1307,7 @@ static int ov2740_suspend(struct device *dev)
>  	struct ov2740 *ov2740 = to_ov2740(sd);
>  
>  	gpiod_set_value_cansleep(ov2740->reset_gpio, 1);
> +	gpiod_set_value_cansleep(ov2740->powerdown_gpio, 1);
>  	clk_disable_unprepare(ov2740->clk);
>  	return 0;
>  }
> @@ -1320,6 +1322,7 @@ static int ov2740_resume(struct device *dev)
>  	if (ret)
>  		return ret;
>  
> +	gpiod_set_value_cansleep(ov2740->powerdown_gpio, 0);
>  	gpiod_set_value_cansleep(ov2740->reset_gpio, 0);
>  	msleep(20);
>  
> @@ -1348,9 +1351,17 @@ static int ov2740_probe(struct i2c_client *client)
>  	if (IS_ERR(ov2740->reset_gpio)) {
>  		return dev_err_probe(dev, PTR_ERR(ov2740->reset_gpio),
>  				     "failed to get reset GPIO\n");
> -	} else if (ov2740->reset_gpio) {
> +	}
> +
> +	ov2740->powerdown_gpio = devm_gpiod_get_optional(dev, "powerdown", GPIOD_OUT_HIGH);
> +	if (IS_ERR(ov2740->powerdown_gpio)) {
> +		return dev_err_probe(dev, PTR_ERR(ov2740->powerdown_gpio),
> +				     "failed to get powerdown GPIO\n");
> +	}
> +
> +	if (ov2740->reset_gpio || ov2740->powerdown_gpio) {
>  		/*
> -		 * Ensure reset is asserted for at least 20 ms before
> +		 * Ensure reset/powerdown is asserted for at least 20 ms before
>  		 * ov2740_resume() deasserts it.
>  		 */
>  		msleep(20);
> -- 
> 2.47.0
> 
>