09.07.2020 12:07, Andy Shevchenko пишет: > On Thu, Jul 9, 2020 at 12:44 AM Dmitry Osipenko <digetx@xxxxxxxxx> wrote: >> 08.07.2020 23:57, Andy Shevchenko пишет: >>> On Wednesday, July 8, 2020, Dmitry Osipenko <digetx@xxxxxxxxx >>> <mailto:digetx@xxxxxxxxx>> wrote: > > ... > >>> I gave a second look and I think my suggestion is wrong. Here is an >>> interesting propagation of the parent device node to its grand son, >>> leaving son’s one untouched. Original code has intentions to do that way. >> >> The [1] says that gpio_chip.parent should point at the "device providing >> the GPIOs". > > Yes, physical device I believe. > >> That's the pdev->dev.parent in the case of this driver. >> MAX77620 is an MFD PMIC device that has virtual sub-devices like GPIO >> controller, PINCTRL and RTC. The MFD is the parent device that provides >> the GPIOs [2]. >> >> [1] >> https://elixir.bootlin.com/linux/v5.8-rc3/source/include/linux/gpio/driver.h#L276 >> >> [2] >> https://elixir.bootlin.com/linux/v5.8-rc3/source/arch/arm64/boot/dts/nvidia/tegra210-p2180.dtsi#L48 >> >> I think the old code was wrong and this patch is correct, please correct >> me if I'm missing something. > > Hmm... I have checked through GPIO drivers I have knowledge of / care > about and PMIC ones do like you suggested in this patch, the rest > (which are instantiated from MFD) take a virtual platform device. > > Looking at DT excerpt I think you're rather right than wrong, so I > leave it to you and maintainers. > Thanks! Okay, waiting for the maintainers then :) Thank you very much for the review!