[PATCH 2/2] drm/rockchip: analogix_dp: Refuse to enable PSR if panel doesn't support it

[Sean Paul]

On Fri, Sep 23, 2016 at 10:06 AM, Tomeu Vizoso
<tomeu.vizoso at collabora.com> wrote:
> There's no point in enabling PSR when the panel doesn't support it.
>
> This also avoids a problem when PSR gets enabled when a CRTC is being
> disabled, because sometimes in that situation the DSP_HOLD_VALID_INTR
> interrupt on which we wait will never arrive. This was observed on
> RK3288 with a panel without PSR (veyron-jaq Chromebook).
>
> It's very easy to reproduce by running the kms_rmfb test in IGT a few
> times.
>
> Signed-off-by: Tomeu Vizoso <tomeu.vizoso at collabora.com>

Thanks for digging into this.

Reviewed-by: Sean Paul <seanpaul at chromium.org>



> Cc: Sean Paul <seanpaul at chromium.org>
> Cc: Yakir Yang <ykk at rock-chips.com>
> Cc: Archit Taneja <architt at codeaurora.org>
> ---
>  drivers/gpu/drm/rockchip/analogix_dp-rockchip.c | 3 +++
>  1 file changed, 3 insertions(+)
>
> diff --git a/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c b/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c
> index e83be157cc2a..8548e8271639 100644
> --- a/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c
> +++ b/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c
> @@ -85,6 +85,9 @@ static void analogix_dp_psr_set(struct drm_encoder *encoder, bool enabled)
>         struct rockchip_dp_device *dp = to_dp(encoder);
>         unsigned long flags;
>
> +       if (!analogix_dp_psr_supported(dp->dev))
> +               return;
> +
>         dev_dbg(dp->dev, "%s PSR...\n", enabled ? "Entry" : "Exit");
>
>         spin_lock_irqsave(&dp->psr_lock, flags);
> --
> 2.7.4
>