If there is no backlight specified in the device tree and the panel has access to the DP AUX channel then create a DP AUX backlight if supported by the panel. Signed-off-by: Rajeev Nandan <rajeevny@xxxxxxxxxxxxxx> --- This patch depends on [1] (drm/panel: panel-simple: Stash DP AUX bus; allow using it for DDC) and the previous patch (2/5) of this series. Changes in v4: - New Changes in v5: - Address review comments and move backlight functions to drm_panel.c (Douglas) - Create and register DP AUX backlight if there is no backlight specified in the device tree and panel has the DP AUX channel. (Douglas) - The new drm_panel_dp_aux_backlight() will do the drm_edp_backlight_supported() check. [1] https://lore.kernel.org/dri-devel/20210524165920.v8.7.I18e60221f6d048d14d6c50a770b15f356fa75092@changeid/ drivers/gpu/drm/panel/panel-simple.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.c index b09be6e..047fad5 100644 --- a/drivers/gpu/drm/panel/panel-simple.c +++ b/drivers/gpu/drm/panel/panel-simple.c @@ -800,6 +800,12 @@ static int panel_simple_probe(struct device *dev, const struct panel_desc *desc, if (err) goto disable_pm_runtime; + if (!panel->base.backlight && panel->aux) { + err = drm_panel_dp_aux_backlight(&panel->base, panel->aux); + if (err) + goto disable_pm_runtime; + } + drm_panel_add(&panel->base); return 0; -- 2.7.4