Hello, Making intensive use of the GPIOs on this SuperIO chip, I triggered a race condition causing apparently the wrong GPIO pins to be modified (and likely read) randomly. For some reason (unclear to me, I'm not used at all to kernel API), request_muxed_region/release_region as it is used in this driver is not sufficient to serialize accesses. Also, reading other drivers for the same chip, I see a different pattern: rather than accessing GPIO registers through the common IO region, this region is only used for device discovery. From there, per-function base address is retrieved, and that IO region gets requested once.
So I fixed the concurrent access by: - using the same access pattern as in other drivers - adding mutexes around IO region accesses Once this was done and I got a bit more comfortable with this driver, chip and gpiolib, I continued and fixed 3 minor issues/lacks. Regards, -- Vincent Pelletier -- To unsubscribe from this list: send the line "unsubscribe linux-gpio" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
