msm: wfd: Adds writeback start/stop functionality.

Removes register/unregister calls and replaces them
with start/stop. No need to pre-register the buffers
anymore.

Change-Id: I2f12c3a5791252ad09032cc628d93fb1dc50fee0
Signed-off-by: Vinay Kalia <vkalia@codeaurora.org>
diff --git a/include/linux/msm_mdp.h b/include/linux/msm_mdp.h
index f3ef5e2..cac7758 100644
--- a/include/linux/msm_mdp.h
+++ b/include/linux/msm_mdp.h
@@ -55,10 +55,8 @@
 #define MSMFB_OVERLAY_PLAY_WAIT _IOWR(MSMFB_IOCTL_MAGIC, 149, \
 						struct msmfb_overlay_data)
 #define MSMFB_WRITEBACK_INIT _IO(MSMFB_IOCTL_MAGIC, 150)
-#define MSMFB_WRITEBACK_REGISTER_BUFFER _IOW(MSMFB_IOCTL_MAGIC, 151, \
-						struct msmfb_writeback_data)
-#define MSMFB_WRITEBACK_UNREGISTER_BUFFER _IOW(MSMFB_IOCTL_MAGIC, 152, \
-						struct msmfb_writeback_data)
+#define MSMFB_WRITEBACK_START _IO(MSMFB_IOCTL_MAGIC, 151)
+#define MSMFB_WRITEBACK_STOP _IO(MSMFB_IOCTL_MAGIC, 152)
 #define MSMFB_WRITEBACK_QUEUE_BUFFER _IOW(MSMFB_IOCTL_MAGIC, 153, \
 						struct msmfb_data)
 #define MSMFB_WRITEBACK_DEQUEUE_BUFFER _IOW(MSMFB_IOCTL_MAGIC, 154, \
@@ -229,6 +227,7 @@
 	int id;
 	uint32_t flags;
 	uint32_t priv;
+	uint32_t iova;
 };
 
 #define MSMFB_NEW_REQUEST -1
@@ -446,14 +445,12 @@
 int get_fb_phys_info(unsigned long *start, unsigned long *len, int fb_num);
 struct fb_info *msm_fb_get_writeback_fb(void);
 int msm_fb_writeback_init(struct fb_info *info);
-int msm_fb_writeback_register_buffer(struct fb_info *info,
-		struct msmfb_writeback_data *data);
+int msm_fb_writeback_start(struct fb_info *info);
 int msm_fb_writeback_queue_buffer(struct fb_info *info,
 		struct msmfb_data *data);
 int msm_fb_writeback_dequeue_buffer(struct fb_info *info,
 		struct msmfb_data *data);
-int msm_fb_writeback_unregister_buffer(struct fb_info *info,
-		struct msmfb_writeback_data *data);
+int msm_fb_writeback_stop(struct fb_info *info);
 int msm_fb_writeback_terminate(struct fb_info *info);
 #endif