On Wed, Dec 05, 2018 at 10:21:04AM +0000, Adam Thomson wrote:
If the previous I2C access failed, how can we be sure that the write back to HW of 0xFF even succeeds? More importantly these error returns won't necessarily stop subsequent calls to controls within the Codec I believe, so you could still see unwanted writes to HW via I2C, if I2C is sporadically operational. Again I don't see this update resolving that. The key thing is to resolve why even just one I2C transaction fails.
Right, it's just not clear what we can constructively do if the I2C bus falls to bits other than log things and the I2C controllers will generally do that themselves. There's no guarantee what made it through to the device or what will in future make it through to the device.