On Thu, Jul 18, 2024 at 9:00 AM Doug Anderson <dianders@xxxxxxxxxxxx> wrote: > > Hi, > > On Wed, Jul 17, 2024 at 6:09 PM Rob Clark <robdclark@xxxxxxxxx> wrote: > > > > On Wed, Jul 17, 2024 at 5:19 PM Doug Anderson <dianders@xxxxxxxxxxxx> wrote: > > > > > > Hi, > > > > > > On Wed, Jul 17, 2024 at 2:58 PM Rob Clark <robdclark@xxxxxxxxx> wrote: > > > > > > > > From: Rob Clark <robdclark@xxxxxxxxxxxx> > > > > > > > > Just a guess on the panel timings, but they appear to work. > > > > > > > > Signed-off-by: Rob Clark <robdclark@xxxxxxxxxxxx> > > > > --- > > > > This adds the panel I have on my lenovo yoga slim 7x laptop. I couldn't > > > > find any datasheet so timings is just a guess. But AFAICT everything > > > > works fine. > > > > > > > > drivers/gpu/drm/panel/panel-edp.c | 2 ++ > > > > 1 file changed, 2 insertions(+) > > > > > > Given that this is a Samsung ATNA<mumble>, is there any chance it's an > > > OLED panel? Should it be supported with the Samsung OLED panel driver > > > like this: > > > > > > https://lore.kernel.org/r/20240715-x1e80100-crd-backlight-v2-0-31b7f2f658a3@xxxxxxxxxx > > > > it is an OLED panel, and I did see that patchset and thought that > > samsung panel driver would work. But changing the compat string on > > the yoga dts only gave me a black screen (and I didn't see any of the > > other mentioned problems with bl control or dpms with panel-edp). So > > :shrug:? It could be I overlooked something else, but it _seems_ like > > panel-edp is fine for this panel. Plus, it would avoid awkwardness if > > it turned out there were other non-samsung 2nd sources, but so far > > with a sample size of two 100% of these laptops have the same panel > > Hmm, OK. One question for you: are you using the "enable" GPIO in > panel-edp? IMO the code handling that GPIO in panel-edp is somewhat > dodgy, but it predates my deeper involvement with panels. I've never > seen an eDP panel that could use panel-edp where it was actually > required--every instance where someone thought it was required was > better modeled by using that GPIO as the backlight enable. On the > other hand, the "enable" GPIO in the Samsung OLED panel driver came > straight from the panel datasheet and it makes sense for it to be in > the panel driver since the backlight is handled straight by the > panel... hmm, at least current dts doesn't have an enable gpio. Which could be why panel-samsung-atna33xc20 wasn't working. It is entirely possible we are relying on something left on by the bootloader. > In any case, I guess if things are working it doesn't really hurt to > take it in panel-edp for now... > I wonder if using compatible="edp-panel" everywhere isn't a great idea if we want to switch drivers later. But I guess that is already water under the bridge (so to speak) BR, -R > > But that was the reason for posting this as an RFC. I was hoping > > someone had some hint about where to find datasheets (my google'ing > > was not successful), etc. > > I don't personally have any hints. > > -Doug >
