[ARM] pxafb: add support for FBIOPAN_DISPLAY by dma braching

dma branching is enabled by extending the current setup_frame_dma()
function to allow a 2nd set of frame/palette dma descriptors to be
used.

As a result, pxafb_dma_buff.dma_desc[], pxafb_dma_buff.pal_desc[]
and pxafb_info.fdadr[] are doubled.

This allows maximum re-use of the current dma setup code, although
the pxafb_info.fdadr[xx] for FBRx register values looks a bit odd.

Signed-off-by: Eric Miao <eric.miao@marvell.com>
Signed-off-by: Eric Miao <ycmiao@ycmiao-hp520.(none)>

1 files changed, 6 insertions, 3 deletions

diff --git a/drivers/video/pxafb.h b/drivers/video/pxafb.h
index 0981938682ef..e0f90f4c467d 100644
--- a/drivers/video/pxafb.h
+++ b/drivers/video/pxafb.h
@@ -54,11 +54,14 @@ enum {
 #define PALETTE_SIZE    (256 * 4)
 #define CMD_BUFF_SIZE   (1024 * 50)
 
+/* NOTE: the palette and frame dma descriptors are doubled to allow
+ * the 2nd set for branch settings (FBRx)
+ */
 struct pxafb_dma_buff {
         unsigned char palette[PAL_MAX * PALETTE_SIZE];
         uint16_t cmd_buff[CMD_BUFF_SIZE];
-        struct pxafb_dma_descriptor pal_desc[PAL_MAX];
-        struct pxafb_dma_descriptor dma_desc[DMA_MAX];
+        struct pxafb_dma_descriptor pal_desc[PAL_MAX * 2];
+        struct pxafb_dma_descriptor dma_desc[DMA_MAX * 2];
 };
 
 struct pxafb_info {
@@ -71,7 +74,7 @@ struct pxafb_info {
         struct pxafb_dma_buff   *dma_buff;
         size_t                  dma_buff_size;
         dma_addr_t              dma_buff_phys;
-        dma_addr_t              fdadr[DMA_MAX];
+        dma_addr_t              fdadr[DMA_MAX * 2];
 
         void __iomem            *video_mem;     /* virtual address of frame buffer */
         unsigned long           video_mem_phys; /* physical address of frame buffer */