On Sun, Sep 24, 2017 at 10:36 PM, Rob Herring <robh@xxxxxxxxxx> wrote: > On Wed, Sep 20, 2017 at 6:56 AM, Linus Walleij <linus.walleij@xxxxxxxxxx> wrote: >> On Sat, Sep 2, 2017 at 11:17 PM, Linus Walleij <linus.walleij@xxxxxxxxxx> wrote: >>>> Normally, we the physical panel is described which would imply all these >>>> settings. Are there lots of panels with this controller that would >>>> justify all these settings? >>> >>> The datasheet for the ili9322 just says it "drives panels" essentially. >>> Googling around gives at hand that it is used pretty frequently in >>> Shenzhen China for adapting different off-the-shelf panels to >>> different inputs. >>> >>> I can't really answer how many of these products that run one or >>> another OS using device tree to describe the configuration. It feels more >>> like I'm paving the road for others to travel. > > Not really a road I want to pave and encourage others. It's good when maintainers say "no"! :) >>>>> + - ilitek,entry-mode: the panel can be connected to various input streams >>>>> + and four of them can be selected by electronic straps on the display. >>>>> + However it is possible to select another mode or override the >>>>> + electronic default with this property. Valid values: >>>>> + 0: 8 bit serial RGB through >>>>> + 1: 8 bit serial RGB aligned >>>>> + 2: 8 bit serial RGB dummy 320x240 >>>>> + 3: 8 bit serial RGB dummy 360x240 >>>>> + 4: disabled >>>>> + 5: 24 bit parallel RGB through >>>>> + 6: 24 bit parallel RGB aligned >>>>> + 7: 24 bit YUV 640Y 320CbCr >>>>> + 8: 24 bit YUV 720Y 360CbCr >>>>> + 9: disabled >>>>> + 10: 8 bit ITU-R BT.656 720Y 360CbCr >>>>> + 11: 8 bit ITU-R BT.656 640Y 320CbCr >>>> >>>> To some extent, we have some standard bindings to describe this. >>> >>> I don't find any. Maybe I'm looking in the wrong places :( > > I guess bus-width is all we have. Normally, this is all implied by the > compatible strings of either the controller, panel or both. > > Another way to look at it is, we already have support for lots of > panels and controllers. If those haven't needed to specify this > information, then why do you? It's a question about devicetree vs driver configuration data altogether. An intuitive thing, gray area. Your intuition is likely better. I feel the same about the people who push too much pin control data into the device tree instead of the driver so I understand the issue. (If it is that.) >>> Also the input modes of ili9322 is coupled with resolution so >>> it would need two more cells or so for resolution so I feel >>> it would over-complicate things for these 12 enumerators. >> >> Can we proceed with these patches? >> >> Any opinion from DT or panel maintainers? > > You have my opinion. I don't think Thierry's will be different. > > My suggestion is to move the settings you need into the panel driver > and out of DT. We can always move things to DT later if it makes > sense. Sure thing. I will take the approach of compatible string like this: compatible = "ilitek,ili9322", "dlink,dir685-panel"; And use the latter compatible to set up all the stuff in the panel driver, what about that? Yours, Linus Walleij -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
