[PATCH v2 3/3] drm/komeda: Fix IS_ERR() vs NULL check in komeda_component_get_avail_scaler()

[cuigaosheng]

Thanks for taking time to review this patch.

Maybe we can submit another separate patch to fix ERR_CAST(st), because I'm not
sure which commit should be used as a fixes-tag.

Also, Maybe we should fix ERR_CAST(st) in komeda_pipeline_get_state_and_set_crtc()
and komeda_component_get_state_and_set_user(), please make another separate patch.

Let me know if there's anything I can do, thanks for your work again!

Gaosheng,

On 2023/7/13 16:54, Liviu Dudau wrote:
> Hello,
>
> On Thu, Jul 13, 2023 at 10:05:56AM +0800, Gaosheng Cui wrote:
>> The komeda_pipeline_get_state() returns an ERR_PTR() on failure, we should
>> use IS_ERR() to check the return value.
> While reviewing the change I've realised that komeda_pipeline_get_state_and_set_crtc()
> is also mishandling the return value from komeda_pipeline_get_state(). If IS_ERR(st) is
> true it should use return ERR_CAST(st), following the same pattern as komeda_pipeline_get_state().
>
> If you don't want to update this patch I can send a separate patch. Otherwise,
> the change looks good to me.
>
> Reviewed-by: Liviu Dudau <liviu.dudau at arm.com>
>
> Best regards,
> Liviu
>
>
>> Fixes: 502932a03fce ("drm/komeda: Add the initial scaler support for CORE")
>> Signed-off-by: Gaosheng Cui <cuigaosheng1 at huawei.com>
>> ---
>>   drivers/gpu/drm/arm/display/komeda/komeda_pipeline_state.c | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/gpu/drm/arm/display/komeda/komeda_pipeline_state.c b/drivers/gpu/drm/arm/display/komeda/komeda_pipeline_state.c
>> index 3276a3e82c62..e9c92439398d 100644
>> --- a/drivers/gpu/drm/arm/display/komeda/komeda_pipeline_state.c
>> +++ b/drivers/gpu/drm/arm/display/komeda/komeda_pipeline_state.c
>> @@ -259,7 +259,7 @@ komeda_component_get_avail_scaler(struct komeda_component *c,
>>   	u32 avail_scalers;
>>   
>>   	pipe_st = komeda_pipeline_get_state(c->pipeline, state);
>> -	if (!pipe_st)
>> +	if (IS_ERR(pipe_st))
>>   		return NULL;
>>   
>>   	avail_scalers = (pipe_st->active_comps & KOMEDA_PIPELINE_SCALERS) ^
>> -- 
>> 2.25.1
>>