On Thu, May 7, 2020 at 2:45 PM Pali Rohár <pali@xxxxxxxxxx> wrote: > On Thursday 07 May 2020 19:27:47 Koba Ko wrote: > > don't understand "registration and deregistration would be optional', > > could you explain more!? > > After your patch led_classdev_register() function is not always called. > And led_classdev_unregister() should not be called when there is no > device registered. I think it's not a strong requirement after the commit https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit?id=1dbb9fb4082ce2a2f1cf9596881ddece062d15d0 -- With Best Regards, Andy Shevchenko