On Wed, Jul 27, 2022 at 12:42 PM Potin Lai <potin.lai.pt@xxxxxxxxx> wrote: > On 7/27/22 18:00, Andy Shevchenko wrote: > > On Wed, Jul 27, 2022 at 8:46 AM Potin Lai <potin.lai.pt@xxxxxxxxx> wrote: ... > >> + data = device_get_match_data(&client->dev); > >> + if (data) { > > This check is redundant. Too much protective programming. Just oblige > > that matched ID has to always have an associated data. > Is it guaranteed that device_get_match_data will not return NULL? I find some examples in other drivers, all of them have a check on returned data. No, but as I said you may guarantee that by obliging developers not to shoot in their feet. > Will it be more appropriate if I move device_get_match_data to probe function, and return EINVAL when we get a NULL pointer from device_get_match_data? Why is this check needed? We do not like dead code. > >> + if (!data->support_mfr_check) > >> + return true; > >> + } -- With Best Regards, Andy Shevchenko