Hi Biju,
Thanks for your patch.
On Thu, May 08, 2025 at 10:50:35AM +0100, Biju Das wrote:
> From: hienhuynh <hien.huynh.px@xxxxxxxxxxx>
>
> This patch is based on the commit 73eb5476df72 ("drm: rcar-du: Support
> panels connected directly to the DPAD outputs").
>
> The RZ DU driver assumes that a bridge is always connected to the DU
> output. This is valid for the HDMI output, but the DPAD output can be
> connected directly to a panel, in which case no bridge is available.
>
> To support this use case, detect whether the entities connected to the DU
> DPAD output is encoders or panels based on the number of ports of their DT
> node, and retrieve the corresponding type of DRM objects. For panels,
> additionally create panel bridge instances.
>
> Signed-off-by: hienhuynh <hien.huynh.px@xxxxxxxxxxx>
> Signed-off-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
Tested on RZ/G3E with the following pipeline:
DU -> adv7513 -> HDMI panel
Reviewed-by: Tommaso Merciai <tommaso.merciai.xr@xxxxxxxxxxxxxx>
Tested-by: Tommaso Merciai <tommaso.merciai.xr@xxxxxxxxxxxxxx>
Thanks & Regards,
Tommaso
> ---
> .../gpu/drm/renesas/rz-du/rzg2l_du_encoder.c | 44 +++++++++++++++++--
> 1 file changed, 40 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_du_encoder.c b/drivers/gpu/drm/renesas/rz-du/rzg2l_du_encoder.c
> index 564ab4cb3d37..5e6dd16705e6 100644
> --- a/drivers/gpu/drm/renesas/rz-du/rzg2l_du_encoder.c
> +++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_du_encoder.c
> @@ -22,6 +22,26 @@
> * Encoder
> */
>
> +static unsigned int rzg2l_du_encoder_count_ports(struct device_node *node)
> +{
> + struct device_node *ports;
> + struct device_node *port;
> + unsigned int num_ports = 0;
> +
> + ports = of_get_child_by_name(node, "ports");
> + if (!ports)
> + ports = of_node_get(node);
> +
> + for_each_child_of_node(ports, port) {
> + if (of_node_name_eq(port, "port"))
> + num_ports++;
> + }
> +
> + of_node_put(ports);
> +
> + return num_ports;
> +}
> +
> static const struct drm_encoder_funcs rzg2l_du_encoder_funcs = {
> };
>
> @@ -50,10 +70,26 @@ int rzg2l_du_encoder_init(struct rzg2l_du_device *rcdu,
> struct drm_bridge *bridge;
> int ret;
>
> - /* Locate the DRM bridge from the DT node. */
> - bridge = of_drm_find_bridge(enc_node);
> - if (!bridge)
> - return -EPROBE_DEFER;
> + /*
> + * Locate the DRM bridge from the DT node. For the DPAD outputs, if the
> + * DT node has a single port, assume that it describes a panel and
> + * create a panel bridge.
> + */
> + if (output == RZG2L_DU_OUTPUT_DPAD0 && rzg2l_du_encoder_count_ports(enc_node) == 1) {
> + struct drm_panel *panel = of_drm_find_panel(enc_node);
> +
> + if (IS_ERR(panel))
> + return PTR_ERR(panel);
> +
> + bridge = devm_drm_panel_bridge_add_typed(rcdu->dev, panel,
> + DRM_MODE_CONNECTOR_DPI);
> + if (IS_ERR(bridge))
> + return PTR_ERR(bridge);
> + } else {
> + bridge = of_drm_find_bridge(enc_node);
> + if (!bridge)
> + return -EPROBE_DEFER;
> + }
>
> dev_dbg(rcdu->dev, "initializing encoder %pOF for output %s\n",
> enc_node, rzg2l_du_output_name(output));
> --
> 2.43.0
>
