[PATCH 10/17] drm/tegra: gem: Use dma_mmap_writecombine()

[Thierry Reding]

From: Thierry Reding <tred...@nvidia.com>

Use the existing API rather than open-coding equivalent functionality
in the driver.

Signed-off-by: Thierry Reding <treding at nvidia.com>
---
 drivers/gpu/drm/tegra/gem.c | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/tegra/gem.c b/drivers/gpu/drm/tegra/gem.c
index 5bc59c5109e0..b513df33f17a 100644
--- a/drivers/gpu/drm/tegra/gem.c
+++ b/drivers/gpu/drm/tegra/gem.c
@@ -310,6 +310,7 @@ const struct vm_operations_struct tegra_bo_vm_ops = {

 int tegra_drm_mmap(struct file *file, struct vm_area_struct *vma)
 {
+       unsigned long vm_pgoff = vma->vm_pgoff;
        struct drm_gem_object *gem;
        struct tegra_bo *bo;
        int ret;
@@ -321,12 +322,19 @@ int tegra_drm_mmap(struct file *file, struct 
vm_area_struct *vma)
        gem = vma->vm_private_data;
        bo = to_tegra_bo(gem);

-       ret = remap_pfn_range(vma, vma->vm_start, bo->paddr >> PAGE_SHIFT,
-                             vma->vm_end - vma->vm_start, vma->vm_page_prot);
-       if (ret)
+       vma->vm_flags &= ~VM_PFNMAP;
+       vma->vm_pgoff = 0;
+
+       ret = dma_mmap_writecombine(gem->dev->dev, vma, bo->vaddr, bo->paddr,
+                                   gem->size);
+       if (ret) {
                drm_gem_vm_close(vma);
+               return ret;
+       }
+
+       vma->vm_pgoff = vm_pgoff;

-       return ret;
+       return 0;
 }

 static struct sg_table *
-- 
2.1.2