Re: [PATCH v2 4/5] drm/solomon: Move device info from ssd130x-i2c to the core driver

Javier Martinez Canillas
2022-04-12T13:06:12Z

On 4/12/22 13:22, Andy Shevchenko wrote:
> On Tue, Apr 12, 2022 at 02:21:08PM +0300, Andy Shevchenko wrote:
>> On Tue, Apr 12, 2022 at 10:07:02AM +0200, Javier Martinez Canillas wrote:
>>> On 4/12/22 09:23, Geert Uytterhoeven wrote:
>>>> On Mon, Apr 11, 2022 at 11:12 PM Javier Martinez Canillas
>>>> <javierm@redhat.com> wrote:
>
> ...
>
>>>>> - ssd130x->device_info = device_get_match_data(dev);
>>>>> +
>>>>> + variant = (enum ssd130x_variants)device_get_match_data(dev);
>>>>
>>>> (uintptr_t), to avoid a cast from pointer to integer of different
>>>> size warning.
>>>>
>>>
>>> Indeed. The kernel test robot reported the same.
>>
>> Not only because of this, but also with the non-NULL pointers I prefer the old
>> style without ugly castings.
>>
>> Instead, you may export the array (in the driver's namespace) and use
>> &info[ID] pointer for the specific device info.
>
> Note that device_get_match_data() has no clue if the data is absent or
> data == (void *)0.
>

Yep, we could make the enum start at 1 and check for !variant but that's
something that will also be prevented by your suggestion to just use the
&info[ID] instead.

--
Best regards,

Javier Martinez Canillas
Linux Engineering
Red Hat