Re: [PATCH] drm/hisilicon: fix build error without fbdev emulation

[Arnd Bergmann]

On Tue, Jul 25, 2017 at 5:53 PM, Daniel Vetter <daniel@xxxxxxxx> wrote:
> On Tue, Jul 25, 2017 at 05:33:25PM +0200, Arnd Bergmann wrote:

>>  drivers/gpu/drm/hisilicon/kirin/kirin_drm_drv.c | 5 ++++-
>>  1 file changed, 4 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/gpu/drm/hisilicon/kirin/kirin_drm_drv.c b/drivers/gpu/drm/hisilicon/kirin/kirin_drm_drv.c
>> index 1178341c3858..d48102d1a7a4 100644
>> --- a/drivers/gpu/drm/hisilicon/kirin/kirin_drm_drv.c
>> +++ b/drivers/gpu/drm/hisilicon/kirin/kirin_drm_drv.c
>> @@ -121,6 +121,7 @@ static int kirin_drm_kms_init(struct drm_device *dev)
>>       /* init kms poll for handling hpd */
>>       drm_kms_helper_poll_init(dev);
>>
>> +#ifdef CONFIG_DRM_FBDEV_EMULATION
>>       priv->fbdev = drm_fbdev_cma_init(dev, 32,
>>                                        dev->mode_config.num_connector);
>>       if (IS_ERR(priv->fbdev)) {
>> @@ -128,11 +129,13 @@ static int kirin_drm_kms_init(struct drm_device *dev)
>>               ret = PTR_ERR(priv->fbdev);
>>               goto err_cleanup_poll;
>>       }
>> -
>> +#endif
>
> Could we instead stop compling out priv->fbdev? There's nothing
> driver-specific here, so teh #ifdef are kinda annoying ...

Yes, I guess that would be better, I just didn't want to do too much
of a rework. If we remove the #ifdef here, we should replace all
instances in that driver.

I'll send a patch to do that and let you pick which one you apply.

> And saving that one pointer in a really huge structure is somewhat silly.

It looks like it's the only member in that structure, but that doesn't
make a big difference either, since there is only one instance in
the system.

>> +#ifdef CONFIG_DRM_FBDEV_EMULATION
>>  err_cleanup_poll:
>>       drm_kms_helper_poll_fini(dev);
>
> poll helpers aren't fbdev specific. Why do we need this? Is this just to
> shut up gcc?

Yes, gcc warns about the unused label here otherwise.

         Arnd