Re: [PATCH v6 23/30] drm/rockchip: analogix_dp: Do not call Analogix code before bind

From: Andrzej Hajda
Date: Thu Apr 12 2018 - 05:54:22 EST


On 05.04.2018 11:49, Enric Balletbo i Serra wrote:
> From: Tomasz Figa <tfiga@xxxxxxxxxxxx>
>
> Driver callbacks, such as system suspend or resume can be called any
> time, specifically they can be called before the component bind
> callback. Let's use dp->adp pointer as a safeguard and skip calling
> Analogix entry points if it is an ERR_PTR().

>From purity PoV I would store either 0 either valid pointer in dp->adp,
but functionally it should be the same.

Reviewed-by: Andrzej Hajda <a.hajda@xxxxxxxxxxx>

Â--
Regards
Andrzej


>
> Signed-off-by: Tomasz Figa <tfiga@xxxxxxxxxxxx>
> Signed-off-by: Thierry Escande <thierry.escande@xxxxxxxxxxxxx>
> Signed-off-by: Enric Balletbo i Serra <enric.balletbo@xxxxxxxxxxxxx>
> Tested-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
> ---
>
> drivers/gpu/drm/rockchip/analogix_dp-rockchip.c | 9 +++++++++
> 1 file changed, 9 insertions(+)
>
> diff --git a/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c b/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c
> index 23317a2269e1..6d45d62466b3 100644
> --- a/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c
> +++ b/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c
> @@ -368,6 +368,8 @@ static void rockchip_dp_unbind(struct device *dev, struct device *master,
> analogix_dp_unbind(dp->adp);
> rockchip_drm_psr_unregister(&dp->encoder);
> dp->encoder.funcs->destroy(&dp->encoder);
> +
> + dp->adp = ERR_PTR(-ENODEV);
> }
>
> static const struct component_ops rockchip_dp_component_ops = {
> @@ -391,6 +393,7 @@ static int rockchip_dp_probe(struct platform_device *pdev)
> return -ENOMEM;
>
> dp->dev = dev;
> + dp->adp = ERR_PTR(-ENODEV);
> dp->plat_data.panel = panel;
>
> ret = rockchip_dp_of_probe(dp);
> @@ -414,6 +417,9 @@ static int rockchip_dp_suspend(struct device *dev)
> {
> struct rockchip_dp_device *dp = dev_get_drvdata(dev);
>
> + if (IS_ERR(dp->adp))
> + return 0;
> +
> return analogix_dp_suspend(dp->adp);
> }
>
> @@ -421,6 +427,9 @@ static int rockchip_dp_resume(struct device *dev)
> {
> struct rockchip_dp_device *dp = dev_get_drvdata(dev);
>
> + if (IS_ERR(dp->adp))
> + return 0;
> +
> return analogix_dp_resume(dp->adp);
> }
> #endif