Re: [PATCH v7 08/10] drm/bridge: ti-sn65dsi86: Add support for the DP AUX bus

From: Lyude Paul
Date: Mon May 24 2021 - 16:29:30 EST


For 7 and 8:

Reviewed-by: Lyude Paul <lyude@xxxxxxxxxx>

On Mon, 2021-05-17 at 13:09 -0700, Douglas Anderson wrote:
> We want to provide our panel with access to the DP AUX channel. The
> way to do this is to let our panel be a child of ours using the fancy
> new DP AUX bus support.
>
> Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
> ---
>
> Changes in v7:
> - Patch to support for DP AUX bus on ti-sn65dsi86 new for v7.
>
>  drivers/gpu/drm/bridge/Kconfig        |  1 +
>  drivers/gpu/drm/bridge/ti-sn65dsi86.c | 13 +++++++++++--
>  2 files changed, 12 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
> index d25e900f07ef..294d0bdd4cbe 100644
> --- a/drivers/gpu/drm/bridge/Kconfig
> +++ b/drivers/gpu/drm/bridge/Kconfig
> @@ -280,6 +280,7 @@ config DRM_TI_SN65DSI86
>         select DRM_PANEL
>         select DRM_MIPI_DSI
>         select AUXILIARY_BUS
> +       select DRM_DP_AUX_BUS
>         help
>           Texas Instruments SN65DSI86 DSI to eDP Bridge driver
>  
> diff --git a/drivers/gpu/drm/bridge/ti-sn65dsi86.c
> b/drivers/gpu/drm/bridge/ti-sn65dsi86.c
> index 42a55d13864b..a59497f7e504 100644
> --- a/drivers/gpu/drm/bridge/ti-sn65dsi86.c
> +++ b/drivers/gpu/drm/bridge/ti-sn65dsi86.c
> @@ -23,6 +23,7 @@
>  #include <drm/drm_atomic.h>
>  #include <drm/drm_atomic_helper.h>
>  #include <drm/drm_bridge.h>
> +#include <drm/drm_dp_aux_bus.h>
>  #include <drm/drm_dp_helper.h>
>  #include <drm/drm_mipi_dsi.h>
>  #include <drm/drm_of.h>
> @@ -1446,19 +1447,27 @@ static int ti_sn_aux_probe(struct auxiliary_device
> *adev,
>         pdata->aux.transfer = ti_sn_aux_transfer;
>         drm_dp_aux_init(&pdata->aux);
>  
> +       ret = devm_of_dp_aux_populate_ep_devices(&pdata->aux);
> +       if (ret)
> +               goto err;
> +
>         /*
>          * The eDP to MIPI bridge parts don't work until the AUX channel is
>          * setup so we don't add it in the main driver probe, we add it now.
>          */
>         ret = ti_sn65dsi86_add_aux_device(pdata, &pdata->bridge_aux,
> "bridge");
>  
> +       if (ret)
> +               goto err;
> +
> +       return 0;
> +err:
>         /*
>          * Clear of_node on any errors. Really this only matters if the
> error
>          * is -EPROBE_DEFER to avoid (again) keep pinctrl from claiming when
>          * it tries the probe again, but it shouldn't hurt on any error.
>          */
> -       if (ret)
> -               adev->dev.of_node = NULL;
> +       adev->dev.of_node = NULL;
>  
>         return ret;
>  }

--
Cheers,
Lyude Paul (she/her)
Software Engineer at Red Hat