atmel_lcdfb: wiring BGR to RGB color mode

Adds different wiring mode for the LCD screen.

The legacy atmel LCDC IP uses a non standard color mode, "BGR-555.1" instead
"RGB-565".  The major part of graphic stacks for embedded systems uses only
"RGB-565".  It is possible to swap LCD IOs instead of doing this bit swapping
by software (See application note AT91SAM9 LCD Controller
http://www.atmel.com/dyn/resources/prod_documents/doc6300.pdf)

This wire swapping is done on the at91sam9rl-ek board (board code
using this patch will come later).

Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Hans-Christian Egtvedt <hcegtvedt@atmel.com>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Andrew Victor <avictor.za@gmail.com>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 10 insertions, 0 deletions

diff --git a/include/video/atmel_lcdc.h b/include/video/atmel_lcdc.h
index 2fd9fad922e5..ed64862c4e18 100644
--- a/include/video/atmel_lcdc.h
+++ b/include/video/atmel_lcdc.h
@@ -22,6 +22,15 @@
 #ifndef __ATMEL_LCDC_H__
 #define __ATMEL_LCDC_H__
 
+
+/* Way LCD wires are connected to the chip:
+ * Some Atmel chips use BGR color mode (instead of standard RGB)
+ * A swapped wiring onboard can bring to RGB mode.
+ */
+#define ATMEL_LCDC_WIRING_BGR   0
+#define ATMEL_LCDC_WIRING_RGB   1
+
+
  /* LCD Controller info data structure, stored in device platform_data */
 struct atmel_lcdfb_info {
         spinlock_t              lock;
@@ -42,6 +51,7 @@ struct atmel_lcdfb_info {
         u8                      saved_lcdcon;
 
         u8                      default_bpp;
+        u8                      lcd_wiring_mode;
         unsigned int            default_lcdcon2;
         unsigned int            default_dmacon;
         void (*atmel_lcdfb_power_control)(int on);