[PATCH v2 1/2] drm/exynos: dp: add of_graph dt binding support for panel

[Rob Herring]

On Wed, Dec 2, 2015 at 5:57 AM, Inki Dae <inki.dae at samsung.com> wrote:
> This patch adds of_graph dt binding support for panel device
> and also keeps the backward compatibility.
>
> i.e.,
> The dts file for Exynos5800 based peach pi board
> has a panel property so we need to keep the backward compatibility.
>
> Changelog v2:
> - return -EINVAL if getting a port node failed.
>
> Signed-off-by: Inki Dae <inki.dae at samsung.com>
> ---
>  drivers/gpu/drm/exynos/exynos_dp_core.c | 21 +++++++++++++++++++--
>  1 file changed, 19 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/exynos/exynos_dp_core.c b/drivers/gpu/drm/exynos/exynos_dp_core.c
> index 94f02a0..0b53045 100644
> --- a/drivers/gpu/drm/exynos/exynos_dp_core.c
> +++ b/drivers/gpu/drm/exynos/exynos_dp_core.c
> @@ -1392,7 +1392,7 @@ static const struct component_ops exynos_dp_ops = {
>  static int exynos_dp_probe(struct platform_device *pdev)
>  {
>         struct device *dev = &pdev->dev;
> -       struct device_node *panel_node, *bridge_node, *endpoint;
> +       struct device_node *panel_node = NULL, *bridge_node, *endpoint = NULL;
>         struct exynos_dp_device *dp;
>         int ret;
>
> @@ -1403,15 +1403,32 @@ static int exynos_dp_probe(struct platform_device *pdev)
>
>         platform_set_drvdata(pdev, dp);
>
> +       /* This is for the backward compatibility. */
>         panel_node = of_parse_phandle(dev->of_node, "panel", 0);
>         if (panel_node) {
>                 dp->panel = of_drm_find_panel(panel_node);
>                 of_node_put(panel_node);
>                 if (!dp->panel)
>                         return -EPROBE_DEFER;
> +       } else {
> +               endpoint = of_graph_get_next_endpoint(dev->of_node, NULL);
> +               if (endpoint) {
> +                       panel_node = of_graph_get_remote_port_parent(endpoint);
> +                       if (panel_node) {
> +                               dp->panel = of_drm_find_panel(panel_node);
> +                               of_node_put(panel_node);
> +                               if (!dp->panel)
> +                                       return -EPROBE_DEFER;
> +                       } else {
> +                               DRM_ERROR("no port node for panel device.\n");
> +                               return -EINVAL;
> +                       }
> +               }

This should be a fairly common sequence, so please make it one. Only
which port is the panel should vary.

Rob