Message ID | 20240628180852.1738922-1-dmitry.torokhov@gmail.com (mailing list archive) |
---|---|
Headers | show |
Series | ARM: pxa: use software nodes/properties for GPIOs | expand |
On Fri, Jun 28, 2024, at 20:08, Dmitry Torokhov wrote: > This series converts legacy pxa boards (spitz, gumstix) to use software > nodes/properties to describe various GPIOs instead of relying on GPIO > lookup tables. The benefit is that structure and behavior is closer to > DT-described GPIOs. > > The very first patch ("ARM: spitz: fix GPIO assignment for backlight") > is actually a fix that IMO should be applied sooner rather than later, > the rest of patches are enhancements. The reason it is sent with the > rest of the series is that later changes contextually depend on it. > > The last patch ("ARM: spitz: Use software nodes for the ADS7846 > touchscreen") soft-depends on corresponding changes by Linus Walleij to > the ads7846 driver in input tree. It compiles without it, but the device > will not sync with display refreshes. I have created an immutable branch > (branched from v6.9) at: > > git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input.git ib/ads7846-hsync > > in case you wish to pull it in. > > Regretfully it was only compiled as I do not have access to the relevant > hardware. Hi Dmitry, I'm happy to pull these in directly, hopefully with some extra review or ack from the maintainers. If there are no negative comments, feel free to resend them to soc@kernel.org for me to pick up. Is your goal to of the series to eventually convert all gpio descriptors over to software nodes, or are you working towards converting all of mach-pxa to DT? In the latter case, note that the reason we kept these specific board files is that they have reasonable support in qemu and you can probably figure out how to test them if you try hard enough. I have not tried myself though, and there is a high chance that current kernels won't boot without extra fixes. If your goal is to change all board files to software nodes, I think we should take a step back, since most of those boards are likely to get removed anyway. Two years ago, I removed almost 90% of the board files remaining at the time after showing that they were pretty much all unused. I kept the ones that either had known users, or that someone wanted to keep for some reason and work on doing the DT conversion. For most of these (including PXA), there has been no work on this in the past two years, so I think we should ask the same question again and see which ones we can just remove this time. Arnd
On Fri, Jun 28, 2024, at 22:59, Arnd Bergmann wrote: > I'm happy to pull these in directly, hopefully with some extra > review or ack from the maintainers. If there are no negative > comments, feel free to resend them to soc@kernel.org for me > to pick up. I just saw that you did in fact send it to soc@kernel.org already. I'll wait for comments then and just merge it if nobody has any objections. Arnd
Hi Arnd, On Fri, Jun 28, 2024 at 10:59:53PM +0200, Arnd Bergmann wrote: > On Fri, Jun 28, 2024, at 20:08, Dmitry Torokhov wrote: > > This series converts legacy pxa boards (spitz, gumstix) to use software > > nodes/properties to describe various GPIOs instead of relying on GPIO > > lookup tables. The benefit is that structure and behavior is closer to > > DT-described GPIOs. > > > > The very first patch ("ARM: spitz: fix GPIO assignment for backlight") > > is actually a fix that IMO should be applied sooner rather than later, > > the rest of patches are enhancements. The reason it is sent with the > > rest of the series is that later changes contextually depend on it. > > > > The last patch ("ARM: spitz: Use software nodes for the ADS7846 > > touchscreen") soft-depends on corresponding changes by Linus Walleij to > > the ads7846 driver in input tree. It compiles without it, but the device > > will not sync with display refreshes. I have created an immutable branch > > (branched from v6.9) at: > > > > git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input.git ib/ads7846-hsync > > > > in case you wish to pull it in. > > > > Regretfully it was only compiled as I do not have access to the relevant > > hardware. > > Hi Dmitry, > > I'm happy to pull these in directly, hopefully with some extra > review or ack from the maintainers. If there are no negative > comments, feel free to resend them to soc@kernel.org for me > to pick up. > > Is your goal to of the series to eventually convert all > gpio descriptors over to software nodes, or are you working > towards converting all of mach-pxa to DT? > > In the latter case, note that the reason we kept these > specific board files is that they have reasonable support in > qemu and you can probably figure out how to test them if you > try hard enough. I have not tried myself though, and there is > a high chance that current kernels won't boot without extra > fixes. > > If your goal is to change all board files to software nodes, > I think we should take a step back, since most of those boards > are likely to get removed anyway. Two years ago, I removed > almost 90% of the board files remaining at the time after > showing that they were pretty much all unused. I kept the > ones that either had known users, or that someone wanted to > keep for some reason and work on doing the DT conversion. > For most of these (including PXA), there has been no work > on this in the past two years, so I think we should ask the > same question again and see which ones we can just remove > this time. I would like to eventually switch everything to the software nodes/property entries. The GPIO lookup tables were introduced before we had software nodes and were really convenient way to describe GPIOs on non-ACPI non-DT boards. However now that we have software nodes/properties we can move away from both custom platform data and lookup tables in the board code and remove platform data support from the drivers, unifying the driver behavior. I am not in any rush with this, so if some boards are on a cutting block I am happy to wait. I started poking at Spitz and the rest of mach-pxa because Linus W sent out a patch to ads7846 ;) and I also remembered that you already dropped bunch of PXA boards that were no longer relevant so I assumed spitz and gumstix still have some use. Could you tell me which ones are likely to stay vs ones that might go? I think arch/arm/mach-s3c/mach-crag* is staying? jornada720? Thanks.
On Fri, Jun 28, 2024, at 23:44, Dmitry Torokhov wrote: > I would like to eventually switch everything to the software > nodes/property entries. The GPIO lookup tables were introduced before we > had software nodes and were really convenient way to describe GPIOs on > non-ACPI non-DT boards. However now that we have software > nodes/properties we can move away from both custom platform data and > lookup tables in the board code and remove platform data support from > the drivers, unifying the driver behavior. Right, makes sense. > I am not in any rush with this, so if some boards are on a cutting block > I am happy to wait. I started poking at Spitz and the rest of mach-pxa > because Linus W sent out a patch to ads7846 ;) and I also remembered > that you already dropped bunch of PXA boards that were no longer > relevant so I assumed spitz and gumstix still have some use. > > Could you tell me which ones are likely to stay vs ones that might go? I > think arch/arm/mach-s3c/mach-crag* is staying? jornada720? I think in the long run all of them will either get removed or converted to DT, though it looks like the DT conversion has not picked up for anything other than ep93xx. For the timeline, I need to ask the same people again that wanted the board files to stay two years ago. omap1 might be a good one to prioritize for software nodes, as that likely still has users and it would help getting closer to a DT version. Arnd
On Fri, Jun 28, 2024 at 8:09 PM Dmitry Torokhov <dmitry.torokhov@gmail.com> wrote: > This series converts legacy pxa boards (spitz, gumstix) to use software > nodes/properties to describe various GPIOs instead of relying on GPIO > lookup tables. The benefit is that structure and behavior is closer to > DT-described GPIOs. Reviewed-by: Linus Walleij <linus.walleij@linaro.org> for the patches I didn't write myself. What this really needs is testing... :/ If nobody is testing, I think you should just send a pull request to soc@kernel.org and users can find out the hard way and help fixing regressions. It's a bit hopeless to work on this sometimes. Yours, Linus Walleij
On Sun, Jun 30, 2024, at 10:07, Linus Walleij wrote: > On Fri, Jun 28, 2024 at 8:09 PM Dmitry Torokhov <dmitry.torokhov@gmail.com> wrote: > >> This series converts legacy pxa boards (spitz, gumstix) to use software >> nodes/properties to describe various GPIOs instead of relying on GPIO >> lookup tables. The benefit is that structure and behavior is closer to >> DT-described GPIOs. > Reviewed-by: Linus Walleij <linus.walleij@linaro.org> > for the patches I didn't write myself. Thanks for the review! > What this really needs is testing... :/ > > If nobody is testing, I think you should just send a pull request > to soc@kernel.org and users can find out the hard way and help > fixing regressions. It's a bit hopeless to work on this sometimes. No need, the patches are already in my patchwork queue and I will just apply them directly. Arnd