Hello all, sub, 8. srp 2023. u 14:53 Marek Vasut <marex@xxxxxxx> napisao je: > > On 7/7/23 17:26, Paulo Pavacic wrote: > > Hello Marek, > > Hi, > > > čet, 6. srp 2023. u 17:26 Marek Vasut <marex@xxxxxxx> napisao je: > >> > >> On 7/6/23 17:18, Paulo Pavacic wrote: > >>> Hello Linus, > >>> > >>> čet, 22. lip 2023. u 10:22 Linus Walleij <linus.walleij@xxxxxxxxxx> napisao je: > >>>> > >>>> On Wed, Jun 21, 2023 at 5:09 PM Paulo Pavacic <pavacic.p@xxxxxxxxx> wrote: > >>>> > >>>>> A lot of modifications to st7701 are required. I believe it would > >>>>> result in a driver that doesn't look or work the same. e.g compare > >>>>> delays between initialization sequences of panel-fannal-c3004 and > >>>>> panel-st7701. I think it would be optimal to create st7701s driver and > >>>>> have special handling for st7701s panels. If there was a flag for > >>>>> whether panel is st7701 or st7701s it would end up looking like a > >>>>> mess. > >>>> > >>>> What matters is if the original authors of the old st7701 driver are > >>>> around and reviewing and testing patches at all. What we need is > >>>> active maintainers. (Added Jagan, Marek & Maya). > >>>> > >>>> I buy the reasoning that the st7701s is perhaps substantially different > >>>> from st7701. > >>>> > >>>> If st7701s is very different then I suppose it needs a separate driver, > >>>> then all we need to to name the driver properly, i.e. > >>>> panel-sitronix-st7701s.c. > >>> > >>> I had in person talk with Paul Kocialkowski and I have concluded that > >>> this is the best solution. > >>> I believe I should rename it to st7701s due to the hardware changes. I > >>> would like to create V5 patch with driver renamed to st7701s. > >>> Please let me know if you agree / disagree. > >> > >> If I recall it right, the ST7701 and ST7701S are basically the same > >> chip, aren't they ? > > > > I'm currently exploring all the differences. There aren't a lot of > > differences, but there are some. > > So far I can see that default register values are different, new > > previously unused registers are now used and there has been some > > reordering of how info is placed in registers [1] (data bits are in > > different order). Moreover, instructions to some commands have been > > changed and meaning of what data bits mean [2][3]. Also, new features > > have been added [2]; there is now PCLKS 3 for example. > > > > You can see few differences in following images. Same images were > > attached in this mail: > > [1] https://ibb.co/NmgbZmy - GAMACTRL_st7701.png > > [2] https://ibb.co/G79y235 - PCLKS2.png > > Ouch. I wonder if this is still something that can be abstracted out > with some helper accessor functions like: > > if (model == ST7701) > write something > else > write the other layout > > Or whether it makes sense to outright have a separate driver. The later > would introduce duplication, but maybe that much duplication is OK. I would like to create new driver because panel-st7701 seems to be outdated and is using non-standard macro (ST7701_WRITE()) and for me it is crashing kernel 5.15. Does anyone have similar issues with it? Br, Paulo
