On Thu, Dec 19, 2024 at 04:05:58PM +0800, Damon Ding wrote:
> If the panel can not be found in the beginning of rockchip_dp_probe()
> using the platform bus, we can still try to find it in analogix_dp_bind()
> through the DP AUX bus after the &analogix_dp_device.aux has been
> initialized.
>
> Signed-off-by: Damon Ding <damon.ding@xxxxxxxxxxxxxx>
> ---
> .../drm/bridge/analogix/analogix_dp_core.c | 19 +++++++++++++++++++
> 1 file changed, 19 insertions(+)
>
> diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
> index 9429c50cc1bc..eae02819e3bb 100644
> --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
> +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
> @@ -19,12 +19,14 @@
> #include <linux/platform_device.h>
>
> #include <drm/bridge/analogix_dp.h>
> +#include <drm/display/drm_dp_aux_bus.h>
> #include <drm/drm_atomic.h>
> #include <drm/drm_atomic_helper.h>
> #include <drm/drm_bridge.h>
> #include <drm/drm_crtc.h>
> #include <drm/drm_device.h>
> #include <drm/drm_edid.h>
> +#include <drm/drm_of.h>
> #include <drm/drm_panel.h>
> #include <drm/drm_print.h>
> #include <drm/drm_probe_helper.h>
> @@ -1733,6 +1735,23 @@ int analogix_dp_bind(struct analogix_dp_device *dp, struct drm_device *drm_dev)
> goto err_disable_pm_runtime;
> }
>
> + if (!dp->plat_data->panel) {
> + /*
> + * If the edp-panel module has not yet been initialized, the
> + * devm_of_dp_aux_populate_bus() function will return 0 and
> + * the done_probing() callback will not be called either.
> + * Consequently, the panel will never be found.
> + *
> + * This is the reason why we do not use the done_probing()
> + * callback and do not check the reture value here.
NAK. It is there for exactly this reason, to account for the panel
driver being not present yet. Please make a use of the done_probing()
callback.
> + */
> + devm_of_dp_aux_populate_bus(&dp->aux, NULL);
> + ret = drm_of_find_panel_or_bridge(dp->dev->of_node, 1, 0,
> + &dp->plat_data->panel, NULL);
> + if (ret)
> + goto err_unregister_aux;
> + }
> +
> ret = analogix_dp_create_bridge(drm_dev, dp);
> if (ret) {
> DRM_ERROR("failed to create bridge (%d)\n", ret);
> --
> 2.34.1
>
--
With best wishes
Dmitry
