1 files changed, 25 insertions, 6 deletions

diff --git a/drivers/video/tegra/fb.c b/drivers/video/tegra/fb.c
index a28ba561477c..9f5bd9a71e68 100644
--- a/drivers/video/tegra/fb.c
+++ b/drivers/video/tegra/fb.c
@@ -79,10 +79,7 @@ static int tegra_fb_open(struct fb_info *info, int user)
 {
 	struct tegra_fb_info *tegra_fb = info->par;
 
-	if (atomic_xchg(&tegra_fb->in_use, 1))
-		return -EBUSY;
-
-	tegra_fb->user_nvmap = NULL;
+	atomic_inc(&tegra_fb->in_use);
 
 	return 0;
 }
@@ -92,6 +89,9 @@ static int tegra_fb_release(struct fb_info *info, int user)
 	struct tegra_fb_info *tegra_fb = info->par;
 	struct fb_var_screeninfo *var = &info->var;
 
+	if (atomic_dec_return(&tegra_fb->in_use))
+		return 0;
+
 	flush_workqueue(tegra_fb->flip_wq);
 
 	if (tegra_fb->win->cur_handle) {
@@ -116,8 +116,6 @@ static int tegra_fb_release(struct fb_info *info, int user)
 		tegra_fb->user_nvmap = NULL;
 	}
 
-	WARN_ON(!atomic_xchg(&tegra_fb->in_use, 0));
-
 	return 0;
 }
 
@@ -586,6 +584,26 @@ surf_err:
 	return err;
 }
 
+static int tegra_fb_mmap(struct fb_info *info, struct vm_area_struct *vma)
+{
+	struct tegra_fb_info *tegra_fb = info->par;
+	struct tegra_dc_win *win = tegra_fb->win;
+	unsigned long size = vma->vm_end - vma->vm_start;
+	unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;
+
+	if (offset + size > win->size)
+		return -EINVAL;
+
+	offset += win->phys_addr + win->offset;
+
+	if (remap_pfn_range(vma, vma->vm_start, offset >> PAGE_SHIFT,
+			    size, PAGE_READONLY))
+		return -EAGAIN;
+
+	vma->vm_flags |= VM_RESERVED;
+	return 0;
+}
+
 /* TODO: implement private window ioctls to set overlay x,y */
 
 static int tegra_fb_ioctl(struct fb_info *info, unsigned int cmd, unsigned long arg)
@@ -674,6 +692,7 @@ static struct fb_ops tegra_fb_ops = {
 	.fb_fillrect = tegra_fb_fillrect,
 	.fb_copyarea = tegra_fb_copyarea,
 	.fb_imageblit = tegra_fb_imageblit,
+	.fb_mmap = tegra_fb_mmap,
 	.fb_ioctl = tegra_fb_ioctl,
 };