drm/exynos: added new funtion to get/put dma address.

this function would be used for drm based 2d acceleration driver
to get/put dma address through gem handle.
when exynos_drm_get_dma_address is called reference count of
gem object would be increased not to be released by gem close and
when exynos_drm_put_dma_address is called the reference count of
this gem object would be decreased to be released.

Signed-off-by: Inki Dae <inki.dae@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/gpu/drm/exynos/exynos_drm_gem.c

@@ -386,6 +386,64 @@ int exynos_drm_gem_create_ioctl(struct drm_device *dev, void *data,
 	return 0;
 }
 
+void *exynos_drm_gem_get_dma_addr(struct drm_device *dev,
+					unsigned int gem_handle,
+					struct drm_file *file_priv)
+{
+	struct exynos_drm_gem_obj *exynos_gem_obj;
+	struct drm_gem_object *obj;
+
+	obj = drm_gem_object_lookup(dev, file_priv, gem_handle);
+	if (!obj) {
+		DRM_ERROR("failed to lookup gem object.\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	exynos_gem_obj = to_exynos_gem_obj(obj);
+
+	if (exynos_gem_obj->flags & EXYNOS_BO_NONCONTIG) {
+		DRM_DEBUG_KMS("not support NONCONTIG type.\n");
+		drm_gem_object_unreference_unlocked(obj);
+
+		/* TODO */
+		return ERR_PTR(-EINVAL);
+	}
+
+	return &exynos_gem_obj->buffer->dma_addr;
+}
+
+void exynos_drm_gem_put_dma_addr(struct drm_device *dev,
+					unsigned int gem_handle,
+					struct drm_file *file_priv)
+{
+	struct exynos_drm_gem_obj *exynos_gem_obj;
+	struct drm_gem_object *obj;
+
+	obj = drm_gem_object_lookup(dev, file_priv, gem_handle);
+	if (!obj) {
+		DRM_ERROR("failed to lookup gem object.\n");
+		return;
+	}
+
+	exynos_gem_obj = to_exynos_gem_obj(obj);
+
+	if (exynos_gem_obj->flags & EXYNOS_BO_NONCONTIG) {
+		DRM_DEBUG_KMS("not support NONCONTIG type.\n");
+		drm_gem_object_unreference_unlocked(obj);
+
+		/* TODO */
+		return;
+	}
+
+	drm_gem_object_unreference_unlocked(obj);
+
+	/*
+	 * decrease obj->refcount one more time because we has already
+	 * increased it at exynos_drm_gem_get_dma_addr().
+	 */
+	drm_gem_object_unreference_unlocked(obj);
+}
+
 int exynos_drm_gem_map_offset_ioctl(struct drm_device *dev, void *data,
 				    struct drm_file *file_priv)
 {

drivers/gpu/drm/exynos/exynos_drm_gem.h

@@ -88,6 +88,24 @@ struct exynos_drm_gem_obj *exynos_drm_gem_create(struct drm_device *dev,
 int exynos_drm_gem_create_ioctl(struct drm_device *dev, void *data,
 				struct drm_file *file_priv);
 
+/*
+ * get dma address from gem handle and this function could be used for
+ * other drivers such as 2d/3d acceleration drivers.
+ * with this function call, gem object reference count would be increased.
+ */
+void *exynos_drm_gem_get_dma_addr(struct drm_device *dev,
+					unsigned int gem_handle,
+					struct drm_file *file_priv);
+
+/*
+ * put dma address from gem handle and this function could be used for
+ * other drivers such as 2d/3d acceleration drivers.
+ * with this function call, gem object reference count would be decreased.
+ */
+void exynos_drm_gem_put_dma_addr(struct drm_device *dev,
+					unsigned int gem_handle,
+					struct drm_file *file_priv);
+
 /* get buffer offset to map to user space. */
 int exynos_drm_gem_map_offset_ioctl(struct drm_device *dev, void *data,
 				    struct drm_file *file_priv);