On Tue, May 19, 2015 at 05:03:29PM +0300, Robert Dolca wrote: > For i2c devices enumerated with ACPI you need to declare both > acpi_match_table and id_table. When using ACPI, the i2c_device_id structure > supplied to the probe function is null and you have to handle this case > in the driver. > > The current name for the i2c client when using ACPI is "HID:UID" where the > UID has 7 or 8 characters and the UID has 2 characters. The UID is not > relevant for identifying the chip so it does not have any practical > purpose. First of all, it is not "HID:UID" since the number after ":" is actually increasing number assigned by the ACPI core. Nothing to do with _UID. Secondly we do not list "_HID:nn" in drivers acpi_match_tables but instead it is either "HID" or "CID", no ":nn" there. > Modifying i2c_match_id we make the comparison by ignoring the UID from the > client name when the device was discovered using ACPI. The comparison is > case insensitive because the ACPI names are uppercase and the DT and ID > table names are lowercase. It would not make sense to have two different > chips with the same name and the only diference being the capitalized > letters. > > With these changes the probe function gets a valid i2c_device_id and the > driver doesn't have to declare acpi_match_table. No. We don't do that for DT and we definitely don't want to mix ACPI identifiers with arbitrary I2C device names. You are not supposed to put ACPI identifiers into i2c_device_id table. -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
