On Thu, Nov 18, 2021 at 11:11 AM Xin Ji <xji@xxxxxxxxxxxxxxxx> wrote:
> @@ -1098,9 +1098,18 @@ static void anx7625_init_gpio(struct anx7625_data *platform)
> /* Gpio for chip power enable */
> platform->pdata.gpio_p_on =
> devm_gpiod_get_optional(dev, "enable", GPIOD_OUT_LOW);
> + if (IS_ERR(platform->pdata.gpio_p_on)) {
> + DRM_DEV_DEBUG_DRIVER(dev, "no enable gpio found\n");
> + platform->pdata.gpio_p_on = NULL;
> + }
> +
> /* Gpio for chip reset */
> platform->pdata.gpio_reset =
> devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
> + if (IS_ERR(platform->pdata.gpio_reset)) {
> + DRM_DEV_DEBUG_DRIVER(dev, "no reset gpio found\n");
> + platform->pdata.gpio_p_on = NULL;
> + }
>
> if (platform->pdata.gpio_p_on && platform->pdata.gpio_reset) {
> platform->pdata.low_power_mode = 1;
devm_gpiod_get_optional() is possible to return NULL (see
https://elixir.bootlin.com/linux/v5.15.2/source/drivers/gpio/gpiolib-devres.c#L250).
Thus, we should use IS_ERR_OR_NULL for checking the return value.
The cases here would work fine except it will skip to print some
informative messages.
Acked-by: Tzung-Bi Shih <tzungbi@xxxxxxxxxx>
