Hi, On Thu, Jun 15, 2017 at 09:51:06AM +0300, Tomi Valkeinen wrote: > On 15/06/17 01:11, Aaro Koskinen wrote: > > When booting v4.12-rc5 on Nokia N900, omapdrm fails to probe and there > > is no display. > > Are you sure it doesn't probe? It fails the omapdss_stack_is_ready() > check? If that's the case then this is easier to debug. Yes I think so, I added debug prints to omap_connect_dssdevs() and pdev_probe(), and it's omapdss_stack_is_ready() that is failing. > > Bisected to: > > > > a09d2bc1503508c17ef3a71c6b1905e3660f3029 is the first bad commit > > commit a09d2bc1503508c17ef3a71c6b1905e3660f3029 > > Author: Peter Ujfalusi <peter.ujfalusi@xxxxxx> > > Date: Tue May 3 22:08:01 2016 +0300 > > > > drm/omap: Use omapdss_stack_is_ready() to check that the display stack is up > > > > Instead of 'guessing' based on aliases of the status of the DSS drivers, > > use the new interface to check that all needed drivers are loaded. > > In this way we can be sure that all needed drivers are loaded so it is > > safe to continue the probing of omapdrm. > > This method will allow the omapdrm to be probed 'headless', without > > outputs. > > > > Signed-off-by: Peter Ujfalusi <peter.ujfalusi@xxxxxx> > > Signed-off-by: Tomi Valkeinen <tomi.valkeinen@xxxxxx> > > > > Reverting the commit seems to fix the issue. > > This is probably "fixed" by adding the display aliases into the n900 dts > file. The aliases should not really be required, although they are > recommended. Without the aliases the order of the displays is random, > and n900 could end up using tv-out as the first display. But even then, > the displays should still work. I'm using up-to-date DTS from the kernel tree. A. -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
