Hi Doug, Le mercredi 13 septembre 2023 à 09:25 -0700, Doug Anderson a écrit : > Hi, > > On Tue, Sep 5, 2023 at 1:16 PM Doug Anderson <dianders@xxxxxxxxxxxx> > wrote: > > > > Paul, > > > > On Mon, Sep 4, 2023 at 2:15 AM Paul Cercueil <paul@xxxxxxxxxxxxxxx> > > wrote: > > > > > > Hi Douglas, > > > > > > Le vendredi 01 septembre 2023 à 16:41 -0700, Douglas Anderson a > > > écrit : > > > > Based on grepping through the source code this driver appears > > > > to be > > > > missing a call to drm_atomic_helper_shutdown() at system > > > > shutdown > > > > time. Among other things, this means that if a panel is in use > > > > that > > > > it > > > > won't be cleanly powered off at system shutdown time. > > > > > > > > The fact that we should call drm_atomic_helper_shutdown() in > > > > the case > > > > of OS shutdown/restart comes straight out of the kernel doc > > > > "driver > > > > instance overview" in drm_drv.c. > > > > > > > > Since this driver uses the component model and shutdown happens > > > > at > > > > the > > > > base driver, we communicate whether we have to call > > > > drm_atomic_helper_shutdown() by seeing if drvdata is non-NULL. > > > > > > > > Suggested-by: Maxime Ripard <mripard@xxxxxxxxxx> > > > > Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx> > > > > > > LGTM. > > > Acked-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx> > > > > Thanks for the Ack! Would you expect this patch to land through > > "drm-misc", or do you expect it to go through some other tree? > > Running: > > > > ./scripts/get_maintainer.pl --scm -f > > drivers/gpu/drm/ingenic/ingenic-drm-drv.c > > > > ...does not show that this driver normally goes through drm-misc, > > but > > it also doesn't show that it goes through any other tree so maybe > > it's > > just an artifact of the way it's tagged in the MAINTAINERS file? If > > it's fine for this to go through drm-misc, I'll probably land it > > (with > > your Ack and Maxime's Review) sooner rather than later just to make > > this patch series less unwieldy. > > > > > > > > --- > > > > This commit is only compile-time tested. > > > > > > > > NOTE: this patch touches a lot more than other similar patches > > > > since > > > > the bind() function is long and we want to make sure that we > > > > unset > > > > the > > > > drvdata if bind() fails. > > > > > > > > While making this patch, I noticed that the bind() function of > > > > this > > > > driver is using "devm" and thus assumes it doesn't need to do > > > > much > > > > explicit error handling. That's actually a bug. As per kernel > > > > docs > > > > [1] > > > > "the lifetime of the aggregate driver does not align with any > > > > of the > > > > underlying struct device instances. Therefore devm cannot be > > > > used and > > > > all resources acquired or allocated in this callback must be > > > > explicitly released in the unbind callback". Fixing that is > > > > outside > > > > the scope of this commit. > > > > > > > > [1] https://docs.kernel.org/driver-api/component.html > > > > > > > > > > Noted, thanks. > > > > FWIW, I think that at least a few other DRM drivers handle this by > > doing some of their resource allocation / acquiring in the probe() > > function and then only doing things in the bind() that absolutely > > need > > to be in the bind. ;-) > > I've been collecting patches that are ready to land in drm-misc but, > right now, I'm not taking this patch since I didn't get any > clarification of whether it should land through drm-misc or somewhere > else. Sorry, you can take it in drm-misc, yes. Cheers, -Paul
