[PATCH v2 4/4] drm/panel-edp: Choose correct preferred mode

From: Hsin-Yi Wang
Date: Thu Nov 02 2023 - 18:13:34 EST


If a non generic edp-panel is under aux-bus, the mode read from edid would
still be selected as preferred and results in multiple preferred modes,
which is ambiguous.

If a hard-coded mode is present, unset the preferred bit of the modes read
from edid.

Signed-off-by: Hsin-Yi Wang <hsinyi@xxxxxxxxxxxx>
---
v1->v2: split patches from drm_modes.
---
drivers/gpu/drm/panel/panel-edp.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/panel/panel-edp.c b/drivers/gpu/drm/panel/panel-edp.c
index 0fb439b5efb1..021322ff9f65 100644
--- a/drivers/gpu/drm/panel/panel-edp.c
+++ b/drivers/gpu/drm/panel/panel-edp.c
@@ -622,10 +622,13 @@ static int panel_edp_get_modes(struct drm_panel *panel,
* and no modes (the generic edp-panel case) because it will clobber
* the display_info that was already set by drm_add_edid_modes().
*/
- if (p->desc->num_timings || p->desc->num_modes)
+ if (p->desc->num_timings || p->desc->num_modes) {
+ /* hard-coded modes present, unset preferred modes from edid. */
+ drm_mode_unset_preferred_modes(connector);
num += panel_edp_get_non_edid_modes(p, connector);
- else if (!num)
+ } else if (!num) {
dev_warn(p->base.dev, "No display modes\n");
+ }

/*
* TODO: Remove once all drm drivers call
--
2.42.0.869.gea05f2083d-goog