Hi Laurent,
On 20/05/2021 07:50, Laurent Pinchart wrote:
> On all platforms except i.MX and Rockchip, the dw-hdmi DT bindings
> require a video output port connected to an HDMI sink (most likely an
> HDMI connector, in rare cases another bridges converting HDMI to another
> protocol). For those platforms, retrieve the next bridge and attach it
> from the dw-hdmi bridge attach handler.
>
> Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>
> Reviewed-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
Nothing jumping out at me here.
Reviewed-by: Kieran Bingham <kieran.bingham+renesas@xxxxxxxxxxxxxxxx>
> ---
> Changes since v1:
>
> - Make missing endpoint a fatal error
> ---
> drivers/gpu/drm/bridge/synopsys/dw-hdmi.c | 54 ++++++++++++++++++++++-
> include/drm/bridge/dw_hdmi.h | 2 +
> 2 files changed, 55 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
> index e7c7c9b9c646..f9065ca4cd88 100644
> --- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
> +++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
> @@ -143,6 +143,7 @@ struct dw_hdmi_phy_data {
> struct dw_hdmi {
> struct drm_connector connector;
> struct drm_bridge bridge;
> + struct drm_bridge *next_bridge;
>
> unsigned int version;
>
> @@ -2775,7 +2776,8 @@ static int dw_hdmi_bridge_attach(struct drm_bridge *bridge,
> struct dw_hdmi *hdmi = bridge->driver_private;
>
> if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR)
> - return 0;
> + return drm_bridge_attach(bridge->encoder, hdmi->next_bridge,
> + bridge, flags);
>
> return dw_hdmi_connector_create(hdmi);
> }
> @@ -3160,6 +3162,52 @@ static void dw_hdmi_init_hw(struct dw_hdmi *hdmi)
> /* -----------------------------------------------------------------------------
> * Probe/remove API, used from platforms based on the DRM bridge API.
> */
> +
> +static int dw_hdmi_parse_dt(struct dw_hdmi *hdmi)
> +{
> + struct device_node *endpoint;
> + struct device_node *remote;
> +
> + if (!hdmi->plat_data->output_port)
> + return 0;
> +
> + endpoint = of_graph_get_endpoint_by_regs(hdmi->dev->of_node,
> + hdmi->plat_data->output_port,
> + -1);
> + if (!endpoint) {
> + /*
> + * On platforms whose bindings don't make the output port
> + * mandatory (such as Rockchip) the plat_data->output_port
> + * field isn't set, so it's safe to make this a fatal error.
> + */
> + dev_err(hdmi->dev, "Missing endpoint in port@%u\n",
> + hdmi->plat_data->output_port);
> + return -ENODEV;
> + }
> +
> + remote = of_graph_get_remote_port_parent(endpoint);
> + of_node_put(endpoint);
> + if (!remote) {
> + dev_err(hdmi->dev, "Endpoint in port@%u unconnected\n",
> + hdmi->plat_data->output_port);
> + return -ENODEV;
> + }
> +
> + if (!of_device_is_available(remote)) {
> + dev_err(hdmi->dev, "port@%u remote device is disabled\n",
> + hdmi->plat_data->output_port);
> + of_node_put(remote);
> + return -ENODEV;
> + }
> +
> + hdmi->next_bridge = of_drm_find_bridge(remote);
> + of_node_put(remote);
> + if (!hdmi->next_bridge)
> + return -EPROBE_DEFER;
> +
> + return 0;
> +}
> +
> struct dw_hdmi *dw_hdmi_probe(struct platform_device *pdev,
> const struct dw_hdmi_plat_data *plat_data)
> {
> @@ -3196,6 +3244,10 @@ struct dw_hdmi *dw_hdmi_probe(struct platform_device *pdev,
> mutex_init(&hdmi->cec_notifier_mutex);
> spin_lock_init(&hdmi->audio_lock);
>
> + ret = dw_hdmi_parse_dt(hdmi);
> + if (ret < 0)
> + return ERR_PTR(ret);
> +
> ddc_node = of_parse_phandle(np, "ddc-i2c-bus", 0);
> if (ddc_node) {
> hdmi->ddc = of_get_i2c_adapter_by_node(ddc_node);
> diff --git a/include/drm/bridge/dw_hdmi.h b/include/drm/bridge/dw_hdmi.h
> index 6a5716655619..2a1f85f9a8a3 100644
> --- a/include/drm/bridge/dw_hdmi.h
> +++ b/include/drm/bridge/dw_hdmi.h
> @@ -126,6 +126,8 @@ struct dw_hdmi_phy_ops {
> struct dw_hdmi_plat_data {
> struct regmap *regm;
>
> + unsigned int output_port;
> +
> unsigned long input_bus_encoding;
> bool use_drm_infoframe;
> bool ycbcr_420_allowed;
>
