On 2020-03-03 16:05, Thierry Reding wrote: > On Tue, Mar 03, 2020 at 02:57:45PM +0000, Peter Rosin wrote: >> >> On 2020-03-03 15:20, Thierry Reding wrote: >>> On Mon, Mar 02, 2020 at 10:53:56PM +0000, Peter Rosin wrote: >>>> On 2020-03-02 21:34, Ville Syrjala wrote: >>>>> From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> >>>>> >>>>> The currently listed dotclock disagrees with the currently >>>>> listed vrefresh rate. Change the dotclock to match the vrefresh. >>>>> >>>>> Someone tell me which (if either) of the dotclock or vreresh is >>>>> correct? >>>> >>>> TL/DR; I do not care if you change the refresh rate or the dotclock. >>>> >>>> The whole entry for that panel in simple-panel is dubious. The panel >>>> is really an LVDS panel (capable of both VESA/Jeida RGB888, selectable >>>> with the SELLVDS pin). With Jeida you can, as usual, omit the 4th >>>> data channel and use the panel with RGB666. In either case, you need >>>> an LVDS signal and nothing else... >>>> >>>> The panel can also rotate the picture 180 degrees using the RL/UD pin. >>>> >>>> These options are of course not expressed in the simple panel driver >>>> (and we have always used fixed signals for those pins in our designs, >>>> IIRC). As far as I'm concerned, the panel can be removed from >>>> simple-panel. Our device trees are nowadays correctly expressing the >>>> hardware with an LVDS encoder between the RGB output and the panel >>>> and points to the panel-lvds driver for the panel. >>> >>> How do you make sure that you always bind against the correct driver? If >>> it matches simple-panel and panel-lvds, it's not deterministically going >>> to pick the right one. Well, it may actually be deterministic on Linux, >>> but perhaps only by accident. >> >> You are probably right that it's fragile, but no problems so far. That >> said, I did wonder why the panel-lvds driver "wins" over simple-panel for >> >> compatible = "sharp,lq150x1lg11", "panel-lvds"; >> >> I figured it was by design and didn't spend too much time thinking about >> it. Maybe I should have? > > It's most likely because panel-lvds.o is linked into the kernel before > panel-simple.o and the first match wins. You may want to move the entry > to panel-lvds to make this a little more robust. Ok, or because I dropped the simple-panel driver when we no longer depended on it. Either way, what do you mean "move to [..] panel-lvds"? It has no list of panels, you have to end with "panel-lvds" in the compatible for the driver to bind. Cheers, Peter _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
