[PATCH] drm/amd/display: fix the ability to use lower resolution modes on eDP

From: Hamza Mahfooz
Date: Thu Sep 14 2023 - 13:54:33 EST


On eDP we can receive invalid modes from dm_update_crtc_state() for
entirely new streams for which drm_mode_set_crtcinfo() shouldn't be
called on. So, instead of calling drm_mode_set_crtcinfo() from within
create_stream_for_sink() we can instead call it from
amdgpu_dm_connector_mode_valid(). Since, we are guaranteed to only call
drm_mode_set_crtcinfo() for valid modes from that function (invalid
modes are rejected by that callback) and that is the only user
of create_validate_stream_for_sink() that we need to call
drm_mode_set_crtcinfo() for (as before commit cb841d27b876
("drm/amd/display: Always pass connector_state to stream validation"),
that is the only place where create_validate_stream_for_sink()'s
dm_state was NULL).

Cc: stable@xxxxxxxxxxxxxxx
Link: https://gitlab.freedesktop.org/drm/amd/-/issues/2693
Fixes: cb841d27b876 ("drm/amd/display: Always pass connector_state to stream validation")
Signed-off-by: Hamza Mahfooz <hamza.mahfooz@xxxxxxx>
---
drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 933c9b5d5252..beef4fef7338 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -6128,8 +6128,6 @@ create_stream_for_sink(struct amdgpu_dm_connector *aconnector,

if (recalculate_timing)
drm_mode_set_crtcinfo(&saved_mode, 0);
- else if (!old_stream)
- drm_mode_set_crtcinfo(&mode, 0);

/*
* If scaling is enabled and refresh rate didn't change
@@ -6691,6 +6689,8 @@ enum drm_mode_status amdgpu_dm_connector_mode_valid(struct drm_connector *connec
goto fail;
}

+ drm_mode_set_crtcinfo(mode, 0);
+
stream = create_validate_stream_for_sink(aconnector, mode,
to_dm_connector_state(connector->state),
NULL);
--
2.42.0