* Document the possibility to pass relative GPIO pin numbers. * Document what platform device IDs to use, so that they do not collide. Signed-off-by: Jean Delvare <khali@xxxxxxxxxxxx> Cc: Peter Korsgaard <peter.korsgaard@xxxxxxxxx> --- Documentation/i2c/muxes/i2c-mux-gpio | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) --- linux-3.7-rc0.orig/Documentation/i2c/muxes/i2c-mux-gpio 2012-07-21 22:58:29.000000000 +0200 +++ linux-3.7-rc0/Documentation/i2c/muxes/i2c-mux-gpio 2012-10-02 23:06:15.131690033 +0200 @@ -63,3 +63,21 @@ static struct platform_device myboard_i2 .platform_data = &myboard_i2cmux_data, }, }; + +If you don't know the absolute GPIO pin numbers at registration time, +you can instead provide a chip name (.chip_name) and relative GPIO pin +numbers, and the i2c-gpio-mux driver will do the work for you, +including deferred probing if the GPIO chip isn't immediately +available. + +Device Registration +------------------- + +When registering your i2c-gpio-mux device, you should pass the number +of any GPIO pin it uses as the device ID. This guarantees that every +instance has a different ID. + +Alternatively, if you don't need a stable device name, you can simply +pass PLATFORM_DEVID_AUTO as the device ID, and the platform core will +assign a dynamic ID to your device. If you do not know the absolute +GPIO pin numbers at registration time, this is even the only option. -- Jean Delvare -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
