On 06/29/2015 03:35 PM, Hyungwon Hwang wrote:

Dear Marek,

On Thu, 25 Jun 2015 15:10:12 +0200 Marek Szyprowski m.szyprowski@samsung.com wrote:

...

Some drivers (like Exynos mixer) calls drm_iommu_attach_device_if_possible before registering crtc, so additional check for NULL crtc pointer is required.

It seems reasonable.

Reviewed-by: Hyungwon Hwang human.hwang@samsung.com

This patch is ok but i think it can remove to use clear_channels function pointer and drm_iommu_attach_device_if_possible function because already drm_iommu_attach_device function checks whether support iommu internally.

I will ready related patch.

Thanks.

...

Signed-off-by: Marek Szyprowski m.szyprowski@samsung.com

drivers/gpu/drm/exynos/exynos_drm_iommu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/exynos/exynos_drm_iommu.c b/drivers/gpu/drm/exynos/exynos_drm_iommu.c index d4ec7465e9cc..d4eb730ba254 100644 --- a/drivers/gpu/drm/exynos/exynos_drm_iommu.c +++ b/drivers/gpu/drm/exynos/exynos_drm_iommu.c @@ -151,7 +151,7 @@ int drm_iommu_attach_device_if_possible(struct exynos_drm_crtc *exynos_crtc, int ret = 0; if (is_drm_iommu_supported(drm_dev)) {

• if (exynos_crtc->ops->clear_channels)
  

• if (exynos_crtc && exynos_crtc->ops->clear_channels)
  exynos_crtc->ops->clear_channels(exynos_crtc);
  

  return drm_iommu_attach_device(drm_dev, subdrv_dev); }