Hi, CK:
I've some idea as below.
On Fri, 2018-05-25 at 13:00 +0800, CK Hu wrote:
> Hi, Stu:
>
> On Fri, 2018-05-25 at 10:34 +0800, stu.hs...@mediatek.com wrote:
> > From: Stu Hsieh <stu.hs...@mediatek.com>
> >
> > This patch create third crtc by third ddp path
> >
>
> Apply this patch before the patch 'Add support for mediatek SOC MT2712'
> because this patch is necessary for mt2712.
>
> > Signed-off-by: Stu Hsieh <stu.hs...@mediatek.com>
> > ---
> > drivers/gpu/drm/mediatek/mtk_drm_drv.c | 5 +++++
> > 1 file changed, 5 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_drv.c
> > b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
> > index b32c4cc8d051..3a866e1d6af4 100644
> > --- a/drivers/gpu/drm/mediatek/mtk_drm_drv.c
> > +++ b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
> > @@ -267,6 +267,11 @@ static int mtk_drm_kms_init(struct drm_device *drm)
> > if (ret < 0)
> > goto err_component_unbind;
> >
> > + ret = mtk_drm_crtc_create(drm, private->data->third_path,
> > + private->data->third_len);
>
> I think you should prevent doing this for mt8173 and mt2701 because that
> two SoC has only two ddp path.
Now, 8173 and 2701 have only two ddp path, there is a problem on run
time.
There are three crtc for drm resource, and there is nothing in third
crtc.
Because 8173 and 2701 have no third ddp, and the third ddp_len is zero.
So, I want to add the condition like following in mtk_crtc_create()
if (path_len == 0)
return 0;
Then, the valur ret is zero and it would not create the null third crtc.
Regards,
Stu
>
> Regards,
> CK
>
> > + if (ret < 0)
> > + goto err_component_unbind;
> > +
> > /* Use OVL device for all DMA memory allocations */
> > np = private->comp_node[private->data->main_path[0]] ?:
> > private->comp_node[private->data->ext_path[0]];
>
>
