Hello Wolfram, On Sun, Dec 3, 2017 at 10:40 PM, Javier Martinez Canillas <javierm@xxxxxxxxxx> wrote: > The buses should honor the firmware interface used to register the device, > but the I2C core reports a MODALIAS of the form i2c:<device> even for I2C > devices registered via OF. > > This means that user-space will never get an OF stype uevent MODALIAS even > when the drivers modules contain aliases exported from both the I2C and OF > device ID tables. For example, an Atmel maXTouch Touchscreen registered by > a DT node with compatible "atmel,maxtouch" has the following module alias: > > $ cat /sys/class/i2c-adapter/i2c-8/8-004b/modalias > i2c:maxtouch > > So udev won't be able to auto-load a module for an OF-only device driver. > Many OF-only drivers duplicate the OF device ID table entries in an I2C ID > table only has a workaround for how the I2C core reports the module alias. > > This patch changes the I2C core to report an OF related MODALIAS uevent if > the device was registered via OF. So for the previous example, after this > patch, the reported MODALIAS for the Atmel maXTouch will be the following: > > $ cat /sys/class/i2c-adapter/i2c-8/8-004b/modalias > of:NtrackpadT<NULL>Catmel,maxtouch > > NOTE: This patch may break out-of-tree drivers that were relying on this > behavior, and only had an I2C device ID table even when the device > was registered via OF. There are no remaining drivers in mainline > that do this, but out-of-tree drivers have to be fixed and define > a proper OF device ID table to have module auto-loading working. > > Signed-off-by: Javier Martinez Canillas <javierm@xxxxxxxxxx> > --- Any comments on this patch? Best regards, Javier
