Hi Andy, On Wed, Apr 24, 2024 at 03:08:14AM +0300, Andy Shevchenko wrote: > Wed, Apr 10, 2024 at 01:24:14PM +0200, Wolfram Sang kirjoitti: > > While working on another cleanup series, I stumbled over the fact that > > some drivers print an error on I2C or SMBus related timeouts. This is > > wrong because it may be an expected state. The client driver on top > > knows this, so let's keep error handling on this level and remove the > > prinouts from controller drivers. > > > > Looking forward to comments, > > I do not see an equivalent change in I²C core. There shouldn't be. The core neither knows if it is okay or not. The client driver knows. > IIRC in our case (DW or i801 or iSMT) we often have this message as the only Often? How often? > one that points to the issues (on non-debug level), it will be much harder to > debug for our customers with this going away. The proper fix is to print the error in the client driver. Maybe this needs a helper for client drivers which they can use like: i2c_report_error(client, retval, flags); The other thing which is also more helpful IMO is that we have trace_events for __i2c_transfer. There, you can see what was happening on the bus before the timeout. It can easily be that, if device X times out, it was because of the transfer before to device Y which locks up the bus. A simple "Bus timed out" message will not help you a lot there. And, keep in mind the false positives I mentioned in the coverletter. All the best, Wolfram
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