Den 24.01.2022 17.42, skrev Rob Herring: > On Mon, Jan 24, 2022 at 10:28 AM Noralf Trønnes <noralf@xxxxxxxxxxx> wrote: >> >> >> >> Den 24.01.2022 17.08, skrev Rob Herring: >>> On Sun, Jan 23, 2022 at 11:25 AM Noralf Trønnes <noralf@xxxxxxxxxxx> wrote: >>>> >>>> Add binding for MIPI DBI compatible SPI panels. >>> >>> I'm sure we already have MIPI DBI panels. What's this for? >>> >> >> It aims to use one driver to cover all MIPI DBI panels where the >> controller setup is loaded from userspace in a firmware file. > > What's the solution when the user wants a splash screen in the > bootloader and also wants multiple panels supported? > In that case the bootloader needs builtin support for the screen. The OS driver can then detect that the controller is configured and just skip the configure stage. I have yet to see someone implement suppport for such a SPI panel in a bootloader though. > Also, 1 driver doesn't dictate 1 compatible. A one to many > relationship is fine and makes the decision entirely the OS's. > >> The cover >> letter points to the discussion where Maxime proposed this: >> >> https://lore.kernel.org/dri-devel/20211129093946.xhp22mvdut3m67sc@houat/ > > The proposal there is: > >> compatible = "panel-spi"; >> model = "panel-from-random-place-42"; > > The same thing can be accomplished with this: > > compatible = "panel-from-random-place-42", "panel-spi"; > > What's the advantage of hijacking 'model'? > That's what Maxime proposed, but having it in the compatible like this is even better. I suppose it's ok for the driver to use the compatible to load the firmware file? Noralf.
