On 05/09/2023 15:31, Lars-Peter Clausen wrote: > On 9/5/23 04:43, Tomas Melin wrote: >> Hi, >> >> Point is, that if the communication to the i2c bus has some temporary >> error like EAGAIN, why could it not be reasonable to try again at a >> later time instead of giving up completely. > > The way probe deferral works, or is supposed to work, is that if a > driver detects that it is missing a resource to initialize the device it > can return EPROBE_DEFER to try again later. Once a new resource becomes > available it will try again. In your case there is no resource > dependency, but just a random failure. So there is no guarantee that > probe will actually be called again since there might not be any new > resources that become available. > > The solution you've implemented might work on your specific platform, > but it does not work by design, it only works by chance. Returning > EPROBE_DEFER for things like IO errors is not the right approach. If you > need a quick hack you can for example write a small userspace script > that will trigger re-probe of the device at system startup. Right, I will need to take a different approach with this. Thanks for the input! Tomas > >
