On Tue, Nov 16, 2021 at 9:44 AM Jani Nikula jani.nikula@linux.intel.com wrote:

Cc: Ville

On Mon, 15 Nov 2021, Angus Ainslie angus@akkea.ca wrote:

...

Lots of monitors nowdays support more than 1024x768 so if the EDID is unknown then add resolutions upto 1920x1080.

IIUC it's supposed to be the fallback that's pretty much guaranteed to work. What's going to happen if we add 1920x1080 and it fails?

Yeah unless we are now in a times where monitors fail to light up these very low resolutions then I don't think adding more here is a good idea. This absolute fallback list is _not_ about making things good, but about getting anything onto the screen. If we really, really need this (and then it needs good reasons) then a defensive approach might be to add more modes, but still leave the old 1024x768 as the preferred one. That would avoid any regression potential.

Otherwise this just becomes a game of "I want to have the best mode for my broken screen without working edid as the default", which is no-go. -Daniel

BR, Jani.

...

Signed-off-by: Angus Ainslie angus@akkea.ca

drivers/gpu/drm/drm_probe_helper.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/drm_probe_helper.c b/drivers/gpu/drm/drm_probe_helper.c index e7e1ee2aa352..5ad66ae9916e 100644 --- a/drivers/gpu/drm/drm_probe_helper.c +++ b/drivers/gpu/drm/drm_probe_helper.c @@ -517,7 +517,7 @@ int drm_helper_probe_single_connector_modes(struct drm_connector *connector,

  if (count == 0 && (connector->status == connector_status_connected ||
                     connector->status == connector_status_unknown))

•         count = drm_add_modes_noedid(connector, 1024, 768);
  

•         count = drm_add_modes_noedid(connector, 1920, 1080);
  count += drm_helper_probe_add_cmdline_mode(connector);
  if (count == 0)
          goto prune;
  

-- Jani Nikula, Intel Open Source Graphics Center