On Thu, Jul 18, 2024 at 9:31 AM Doug Anderson <dianders@xxxxxxxxxxxx> wrote: > > Hi, > > On Thu, Jul 18, 2024 at 9:25 AM Rob Clark <robdclark@xxxxxxxxx> wrote: > > > > 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. > > That would be my best guess. Is there any way for you to find out if > there's an enable GPIO? presumably it would be in the ACPI dump (which I've not much of a clue what I'm looking for there) BR, -R > > > > 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) > > For panels that aren't OLED it's all very standard and we're kinda > forced to use something generic since manufacturers want lots of 2nd > (and 3rd and 4th and ...) sourcing. As far as I've been able to tell > you can't do 2nd sourcing between OLED panels and other panels since > the wires hooked up to the panels are a little different for the OLED > panels and the power sequencing is a bit different. It would also be > pretty obvious to an end user if some of their devices had an OLED > panel and some didn't. I'm not aware of OLED panels other than the > Samsung ones, but I haven't done any real research here... > > -Doug >
