2021-11-19 01:58:20

by Xin Ji

Subject: [PATCH v2] drm/bridge: anx7625: Check GPIO description to avoid crash

As GPIO probe function "devm_gpiod_get_optional()" may return error
code, driver should identify GPIO desc as NULL to avoid crash.

Acked-by: Tzung-Bi Shih <[email protected]>
Signed-off-by: Xin Ji <[email protected]>
---
drivers/gpu/drm/bridge/analogix/anx7625.c | 9 +++++++++
1 file changed, 9 insertions(+)

diff --git a/drivers/gpu/drm/bridge/analogix/anx7625.c b/drivers/gpu/drm/bridge/analogix/anx7625.c
index 001fb39d9919..652ae814246d 100644
--- a/drivers/gpu/drm/bridge/analogix/anx7625.c
+++ b/drivers/gpu/drm/bridge/analogix/anx7625.c
@@ -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_OR_NULL(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_OR_NULL(platform->pdata.gpio_reset)) {
+ DRM_DEV_DEBUG_DRIVER(dev, "no reset gpio found\n");
+ platform->pdata.gpio_reset = NULL;
+ }

if (platform->pdata.gpio_p_on && platform->pdata.gpio_reset) {
platform->pdata.low_power_mode = 1;
--
2.25.1

2022-01-04 13:37:15

by Robert Foss

Subject: Re: [PATCH v2] drm/bridge: anx7625: Check GPIO description to avoid crash

On Fri, 19 Nov 2021 at 02:58, Xin Ji <[email protected]> wrote:
>
> As GPIO probe function "devm_gpiod_get_optional()" may return error
> code, driver should identify GPIO desc as NULL to avoid crash.
>
> Acked-by: Tzung-Bi Shih <[email protected]>
> Signed-off-by: Xin Ji <[email protected]>
> ---
> drivers/gpu/drm/bridge/analogix/anx7625.c | 9 +++++++++
> 1 file changed, 9 insertions(+)
>
> diff --git a/drivers/gpu/drm/bridge/analogix/anx7625.c b/drivers/gpu/drm/bridge/analogix/anx7625.c
> index 001fb39d9919..652ae814246d 100644
> --- a/drivers/gpu/drm/bridge/analogix/anx7625.c
> +++ b/drivers/gpu/drm/bridge/analogix/anx7625.c
> @@ -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_OR_NULL(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_OR_NULL(platform->pdata.gpio_reset)) {
> + DRM_DEV_DEBUG_DRIVER(dev, "no reset gpio found\n");
> + platform->pdata.gpio_reset = NULL;
> + }
>
> if (platform->pdata.gpio_p_on && platform->pdata.gpio_reset) {
> platform->pdata.low_power_mode = 1;
> --
> 2.25.1
>

Reviewed-by: Robert Foss <[email protected]>

2022-01-04 13:39:24

by Robert Foss

Subject: Re: [PATCH v2] drm/bridge: anx7625: Check GPIO description to avoid crash

Applied to drm-misc-next