On Thursday 01 September 2011, Stephen Warren wrote: > One question: When we add this field, how do drivers tell whether a value > of 0 is an uninitialized field, or a legitimate GPIO value of 0? Should we > add a flag to indicate validity, or just work hard to not enable driver- > side code to use this value until we've fixed up all places that instantiate > the driver to initialize the field to some invalid value like -1? I think it's enough to coordinate the driver with the initialization of the i2c data. If a driver requires a GPIO number, it can assume that it's valid. Drivers that don't need one don't care. If it's an optional feature, you might want to either use platform_data after all, or use different identifiers for devices that have a gpio vs. those that have none -- in effect those are different types of devices handled by the same driver. Arnd _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/devel
