On Sun, 01 Dec 2024, Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx> wrote:
> Extend drm_bridge_connector code to read the EDID and use it to update
> connector status if the bridge chain implements HDMI bridge. Performing
> it from the generic location minimizes individual bridge's code and
> enforces standard behaviour from all corresponding drivers.
>
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
> ---
> drivers/gpu/drm/display/drm_bridge_connector.c | 67 ++++++++++++++++++++------
> 1 file changed, 53 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/gpu/drm/display/drm_bridge_connector.c b/drivers/gpu/drm/display/drm_bridge_connector.c
> index 12ab9f14cc8a8672478ae2804c9a68d766d88ea5..71ae3b2c9049016d1cc0d39a787f6461633efd53 100644
> --- a/drivers/gpu/drm/display/drm_bridge_connector.c
> +++ b/drivers/gpu/drm/display/drm_bridge_connector.c
> @@ -17,6 +17,7 @@
> #include <drm/drm_edid.h>
> #include <drm/drm_managed.h>
> #include <drm/drm_modeset_helper_vtables.h>
> +#include <drm/drm_print.h>
> #include <drm/drm_probe_helper.h>
> #include <drm/display/drm_hdmi_state_helper.h>
>
> @@ -175,17 +176,55 @@ static void drm_bridge_connector_disable_hpd(struct drm_connector *connector)
> * Bridge Connector Functions
> */
>
> +static const struct drm_edid *
> +drm_bridge_connector_read_edid(struct drm_connector *connector,
> + enum drm_connector_status status)
> +{
> + struct drm_bridge_connector *bridge_connector =
> + to_drm_bridge_connector(connector);
> + const struct drm_edid *drm_edid;
> + struct drm_bridge *bridge;
> +
> + bridge = bridge_connector->bridge_edid;
> + if (!bridge)
> + return NULL;
> +
> + if (status != connector_status_connected)
> + return NULL;
> +
> + drm_edid = drm_bridge_edid_read(bridge, connector);
> + if (!drm_edid_valid(drm_edid)) {
What's the case this check is for?
My preference would be that bridge->funcs->edid_read() uses
drm_edid_read*() family of functions that do the checks and return the
EDID.
There are some cases that just allocate a blob and return it. Would be
nice if they could be converted, but in the mean time could use
drm_edid_valid() right there. Additional validity checks are redundant.
BR,
Jani.
> + drm_edid_free(drm_edid);
> + return NULL;
> + }
> +
> + return drm_edid;
> +}
> +
> static enum drm_connector_status
> drm_bridge_connector_detect(struct drm_connector *connector, bool force)
> {
> struct drm_bridge_connector *bridge_connector =
> to_drm_bridge_connector(connector);
> struct drm_bridge *detect = bridge_connector->bridge_detect;
> + struct drm_bridge *hdmi = bridge_connector->bridge_hdmi;
> enum drm_connector_status status;
>
> if (detect) {
> status = detect->funcs->detect(detect);
>
> + if (hdmi) {
> + const struct drm_edid *drm_edid;
> + int ret;
> +
> + drm_edid = drm_bridge_connector_read_edid(connector, status);
> + ret = drm_atomic_helper_connector_hdmi_update_edid(connector, drm_edid);
> + if (ret)
> + drm_warn(connector->dev, "updating EDID failed with %d\n", ret);
> +
> + drm_edid_free(drm_edid);
> + }
> +
> drm_bridge_connector_hpd_notify(connector, status);
> } else {
> switch (connector->connector_type) {
> @@ -246,29 +285,29 @@ static const struct drm_connector_funcs drm_bridge_connector_funcs = {
> static int drm_bridge_connector_get_modes_edid(struct drm_connector *connector,
> struct drm_bridge *bridge)
> {
> + struct drm_bridge_connector *bridge_connector =
> + to_drm_bridge_connector(connector);
> + struct drm_bridge *hdmi = bridge_connector->bridge_hdmi;
> enum drm_connector_status status;
> const struct drm_edid *drm_edid;
> - int n;
>
> status = drm_bridge_connector_detect(connector, false);
> if (status != connector_status_connected)
> - goto no_edid;
> + return 0;
>
> - drm_edid = drm_bridge_edid_read(bridge, connector);
> - if (!drm_edid_valid(drm_edid)) {
> + /* In HDMI setup the EDID has been read and handled as a part of .detect() */
> + if (!hdmi) {
> + drm_edid = drm_bridge_connector_read_edid(connector, status);
> + if (!drm_edid) {
> + drm_edid_connector_update(connector, NULL);
> + return 0;
> + }
> +
> + drm_edid_connector_update(connector, drm_edid);
> drm_edid_free(drm_edid);
> - goto no_edid;
> }
>
> - drm_edid_connector_update(connector, drm_edid);
> - n = drm_edid_connector_add_modes(connector);
> -
> - drm_edid_free(drm_edid);
> - return n;
> -
> -no_edid:
> - drm_edid_connector_update(connector, NULL);
> - return 0;
> + return drm_edid_connector_add_modes(connector);
> }
>
> static int drm_bridge_connector_get_modes(struct drm_connector *connector)
--
Jani Nikula, Intel
