Re: [PATCH v7 00/48] atmel_mxt_ts misc

[Dmitry Osipenko]

23.03.2020 05:25, Wang, Jiada ÐÐÑÐÑ:
> Hello Dmitry
> 
> On 2020/03/21 0:53, Dmitry Osipenko wrote:
>> Hello Jiada,
>>
>> 20.03.2020 06:37, Wang, Jiada ÐÐÑÐÑ:
>>> 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.