On Mon, 27 Sep 2021, Luis Chamberlain wrote:

This adds a new selftest module which can be used to test sysfs, which
would otherwise require using an existing driver. This lets us muck
with a template driver to test breaking things without affecting
system behaviour or requiring the dependencies of a real device
driver.

A series of 28 tests are added. Support for using two device types are
supported:

  * misc
  * block

I suppose the selftests will run for more than 45 seconds (default 
kselftest timeout), so you probably also want to set timeout to something 
sensible in tools/testing/selftests/sysfs/settings file (0 would disable 
it).

Miroslav