On Tue, Nov 30, 2021 at 5:20 PM Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> wrote: > > On Tue, Nov 30, 2021 at 06:14:01PM +0200, Andy Shevchenko wrote: > > On Tue, Nov 30, 2021 at 04:41:23PM +0100, Bartosz Golaszewski wrote: > > ... > > > Not sure I understand the proposal. Can you provide couple of (simplest) > > examples? > > > > And also it sounds like reinventing a wheel. What problem do you have that you > > need to solve this way? > > Have you seen these: > drivers/gpio/gpio-dwapb.c > drivers/mfd/intel_quark_i2c_gpio.c > ? > > GPIO driver has a main (controller level) node along with children on per bank > basis. Currently it works with the provided approach (see second driver). > > -- > With Best Regards, > Andy Shevchenko > > Yep, I know dwapd. What happens in probe is that each bank device is created using the properties from the associated child fwnode but the parent device's fwnode is actually assigned as the gpiochip's fwnode. This is logically wrong and OF doesn't do it - it assigns the child of_node to the child device if gpio_chip->of_node is assigned in the driver. I'm not sure if ACPI does this. Non-OF drivers don't have a way to do this and this patch enables it. I want to add it mostly because gpio-sim can then use the software node to identify the device in the configfs by that software node but IMO this is logically correct too. Bart
