23.03.2020 05:25, Wang, Jiada пишет: > Hello Dmitry > > On 2020/03/21 0:53, Dmitry Osipenko wrote: >> Hello Jiada, >> >> 20.03.2020 06:37, Wang, Jiada пишет: >>> Hello Dmitry >>> >>> I have submitted v8 patch-set to address your comments towards v7 >>> patch-set, >>> most of checkpatch warnings and errors have been addressed, >>> >>> But I didn't update for following two types of warnings >>> since I want to keep consistency with legacy code >>> >>> WARNING: DEVICE_ATTR unusual permissions '0600' used >>> #290: FILE: drivers/input/touchscreen/atmel_mxt_ts.c:3761: >>> +static DEVICE_ATTR(debug_v2_enable, 0600, NULL, >> >> What will happen if you'll use 0644? Will an empty line be returned or >> driver will crash? >> > debug_v2_enable doesn't have .show callback implemented, so after change > permission to 644, read of it results in an I/O error, > > for other 0600 permission interfaces (t38_data, t25 and debug_enable) > added in this series, > change to 644 can return expected information when read. > > Do you think it's better to change debug_v2_enable to 0200, > and others to 0644? Since the debug_enable has mxt_debug_enable_show(), the same should be done for debug_v2_enable, for consistency. The permissions should be 0644 for everything that is read/write. The 0200 should be used for everything that is root-only and write-only.
