Re: [PATCH 3/6] drm/bridge: ti-sn65dsi86: Add some 100 us delays

From: Robert Foss
Date: Thu Jul 29 2021 - 07:48:50 EST


Hey Doug,

Thanks for submitting this.

On Wed, 28 Jul 2021 at 18:46, Douglas Anderson <dianders@xxxxxxxxxxxx> wrote:
>
> The manual has always said that we need 100 us delays in a few
> places. Though it hasn't seemed to be a big deal to skip these, let's
> add them in case it makes something happier.
>
> NOTE: this fixes no known issues but it seems good to make it right.
>
> Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
> ---
>
> drivers/gpu/drm/bridge/ti-sn65dsi86.c | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/drivers/gpu/drm/bridge/ti-sn65dsi86.c b/drivers/gpu/drm/bridge/ti-sn65dsi86.c
> index 5e932070a1c3..cd0fccdd8dfd 100644
> --- a/drivers/gpu/drm/bridge/ti-sn65dsi86.c
> +++ b/drivers/gpu/drm/bridge/ti-sn65dsi86.c
> @@ -307,6 +307,9 @@ static int __maybe_unused ti_sn65dsi86_resume(struct device *dev)
> return ret;
> }
>
> + /* td2: min 100 us after regulators before enabling the GPIO */
> + usleep_range(100, 110);
> +
> gpiod_set_value(pdata->enable_gpio, 1);
>
> /*
> @@ -1096,6 +1099,9 @@ static void ti_sn_bridge_pre_enable(struct drm_bridge *bridge)
>
> if (!pdata->refclk)
> ti_sn65dsi86_enable_comms(pdata);
> +
> + /* td7: min 100 us after enable before DSI data */
> + usleep_range(100, 110);
> }
>
> static void ti_sn_bridge_post_disable(struct drm_bridge *bridge)
> --
> 2.32.0.432.gabb21c7263-goog
>

Acked-by: Robert Foss <robert.foss@xxxxxxxxxx>