Hi Marek,
Thank you for the patch.
On Sat, May 15, 2021 at 10:46:56PM +0200, Marek Vasut wrote:
> Decoder input LVDS format is a property of the decoder chip or even
> its strapping. Handle data-mapping the same way lvds-panel does. In
> case data-mapping is not present, do nothing, since there are still
> legacy bindings which do not specify this property.
>
> Signed-off-by: Marek Vasut <marex@xxxxxxx>
> Cc: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
> Cc: Sam Ravnborg <sam@xxxxxxxxxxxx>
> To: dri-devel@xxxxxxxxxxxxxxxxxxxxx
> ---
> drivers/gpu/drm/bridge/lvds-codec.c | 50 +++++++++++++++++++++++++++++
> 1 file changed, 50 insertions(+)
>
> diff --git a/drivers/gpu/drm/bridge/lvds-codec.c b/drivers/gpu/drm/bridge/lvds-codec.c
> index 8a7cb267ab14..33f992d52902 100644
> --- a/drivers/gpu/drm/bridge/lvds-codec.c
> +++ b/drivers/gpu/drm/bridge/lvds-codec.c
> @@ -23,6 +23,7 @@ struct lvds_codec {
> struct regulator *vcc;
> struct gpio_desc *powerdown_gpio;
> u32 connector_type;
> + unsigned int bus_format;
> };
>
> static inline struct lvds_codec *to_lvds_codec(struct drm_bridge *bridge)
> @@ -69,10 +70,33 @@ static void lvds_codec_disable(struct drm_bridge *bridge)
> "Failed to disable regulator \"vcc\": %d\n", ret);
> }
>
> +static bool lvds_codec_mode_fixup(struct drm_bridge *bridge,
> + const struct drm_display_mode *mode,
> + struct drm_display_mode *adj)
> +{
> + struct lvds_codec *lvds_codec = to_lvds_codec(bridge);
> + struct drm_encoder *encoder = bridge->encoder;
> + struct drm_device *ddev = encoder->dev;
> + struct drm_connector *connector;
> +
> + /* If 'data-mapping' was not specified, do nothing. */
> + if (!lvds_codec->bus_format)
> + return true;
> +
> + /* Patch in the LVDS format */
> + list_for_each_entry(connector, &ddev->mode_config.connector_list, head) {
> + drm_display_info_set_bus_formats(&connector->display_info,
> + &lvds_codec->bus_format, 1);
> + }
This part bothers me, as the format at the input of the LVDS decoder
doesn't match the format on the connector. Shouldn't you implement
.atomic_get_output_bus_fmts() instead ?
> +
> + return true;
> +}
> +
> static const struct drm_bridge_funcs funcs = {
> .attach = lvds_codec_attach,
> .enable = lvds_codec_enable,
> .disable = lvds_codec_disable,
> + .mode_fixup = lvds_codec_mode_fixup,
> };
>
> static int lvds_codec_probe(struct platform_device *pdev)
> @@ -81,6 +105,7 @@ static int lvds_codec_probe(struct platform_device *pdev)
> struct device_node *panel_node;
> struct drm_panel *panel;
> struct lvds_codec *lvds_codec;
> + const char *mapping;
I would have moved this variable to the if () { ... } below, but maybe
that's just me.
> u32 val;
>
> lvds_codec = devm_kzalloc(dev, sizeof(*lvds_codec), GFP_KERNEL);
> @@ -133,6 +158,31 @@ static int lvds_codec_probe(struct platform_device *pdev)
> DRM_BUS_FLAG_PIXDATA_SAMPLE_NEGEDGE;
> }
>
> + /*
> + * Decoder input LVDS format is a property of the decoder chip or even
> + * its strapping. Handle data-mapping the same way lvds-panel does. In
> + * case data-mapping is not present, do nothing, since there are still
> + * legacy bindings which do not specify this property.
> + */
> + if (lvds_codec->connector_type != DRM_MODE_CONNECTOR_LVDS) {
> + ret = of_property_read_string(dev->of_node, "data-mapping",
> + &mapping);
> + if (ret < 0) {
> + dev_err(dev, "missing 'data-mapping' DT property\n");
> + } else {
> + if (!strcmp(mapping, "jeida-18")) {
> + lvds_codec->bus_format = MEDIA_BUS_FMT_RGB666_1X7X3_SPWG;
> + } else if (!strcmp(mapping, "jeida-24")) {
> + lvds_codec->bus_format = MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA;
> + } else if (!strcmp(mapping, "vesa-24")) {
> + lvds_codec->bus_format = MEDIA_BUS_FMT_RGB888_1X7X4_SPWG;
> + } else {
> + dev_err(dev, "invalid 'data-mapping' DT property\n");
> + return -EINVAL;
> + }
> + }
> + }
> +
> /*
> * The panel_bridge bridge is attached to the panel's of_node,
> * but we need a bridge attached to our of_node for our user
--
Regards,
Laurent Pinchart
