On 04/20/2015 03:28 PM, Chris Wilson wrote: > The intention of using video=<connector>:<mode> is primarily to select > the user's preferred resolution at startup. Currently we always create a > new mode irrespective of whether the monitor has a native mode at the > desired resolution. This has the issue that we may then select the fake > mode rather the native mode during fb_helper->inital_config() and so > if the fake mode is invalid we then end up with a loss of signal. Oops. > This invalid fake mode would also be exported to userspace, who > potentially may make the same mistake. > > To avoid this issue, we filter out the added command line mode if we > detect the desired resolution (and clock if specified) amongst the > probed modes. This fixes the immediate problem of adding a duplicate > mode, but perhaps more generically we should avoid adding a GTF mode if > the monitor has an EDID that is not GTF-compatible, or similarly for > CVT. > > A second issue sneaked into this patch is to add the cmdline mode mode > ahead of the absolute fallback 1024x768 mode. That is if the user has > specified a mode that we create as a fallback, we do not need to add a > second unused fallback mode. > > Fixes regression from > > commit eaf99c749d43ae74ac7ffece5512f3c73f01dfd2 > Author: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> > Date: Wed Aug 6 10:08:32 2014 +0200 > > drm: Perform cmdline mode parsing during connector initialisation > > that breaks HDMI output on BeagleBone Black with LG TV (model 19LS4R-ZA). > > v2: Explicitly delete our earlier cmdline mode > > Reported-by: Radek Dostál <rd@xxxxxxxxxxxxxxx> > Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> > Cc: Radek Dostál <rd@xxxxxxxxxxxxxxx> > Cc: Jesse Barnes <jbarnes@xxxxxxxxxxxxxxxx> > Cc: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > Cc: Daniel Vetter <daniel.vetter@xxxxxxxx> > Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx > Cc: Julia Lemire <jlemire@xxxxxxxxxx> > Cc: Dave Airlie <airlied@xxxxxxxxxx> > Cc: stable@xxxxxxxxxxxxxxx works now :) Tested-by: Radek Dostál <rd@xxxxxxxxxxxxxxx> Thanks, Radek -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html