[ARM] amba-clcd: Allow RGB555 and RGB565 with 16bpp

Some folk want to use RGB555 rather tahn RGB565 with amba-clcd.
Allow amba-clcd to accept either pixel format.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

diff --git a/drivers/video/amba-clcd.c b/drivers/video/amba-clcd.c
index b2187175d03fcde37c6daa66f240b0cdb36c4a71..6761b68c35e97182046e1774d1755ef810423bb7 100644 (file)
--- a/drivers/video/amba-clcd.c
+++ b/drivers/video/amba-clcd.c
@@ -116,9 +116,10 @@ clcdfb_set_bitfields(struct clcd_fb *fb, struct fb_var_screeninfo *var)
        int ret = 0;
 
        memset(&var->transp, 0, sizeof(var->transp));
-       memset(&var->red, 0, sizeof(var->red));
-       memset(&var->green, 0, sizeof(var->green));
-       memset(&var->blue, 0, sizeof(var->blue));
+
+       var->red.msb_right = 0;
+       var->green.msb_right = 0;
+       var->blue.msb_right = 0;
 
        switch (var->bits_per_pixel) {
        case 1:
@@ -133,34 +134,20 @@ clcdfb_set_bitfields(struct clcd_fb *fb, struct fb_var_screeninfo *var)
                var->blue.offset        = 0;
                break;
        case 16:
-               var->red.length         = 5;
-               var->green.length       = 6;
-               var->blue.length        = 5;
-               if (fb->panel->cntl & CNTL_BGR) {
-                       var->red.offset         = 11;
-                       var->green.offset       = 5;
-                       var->blue.offset        = 0;
-               } else {
-                       var->red.offset         = 0;
-                       var->green.offset       = 5;
-                       var->blue.offset        = 11;
-               }
+               var->red.length = 5;
+               var->blue.length = 5;
+               /*
+                * Green length can be 5 or 6 depending whether
+                * we're operating in RGB555 or RGB565 mode.
+                */
+               if (var->green.length != 5 && var->green.length != 6)
+                       var->green.length = 6;
                break;
        case 32:
                if (fb->panel->cntl & CNTL_LCDTFT) {
                        var->red.length         = 8;
                        var->green.length       = 8;
                        var->blue.length        = 8;
-
-                       if (fb->panel->cntl & CNTL_BGR) {
-                               var->red.offset         = 16;
-                               var->green.offset       = 8;
-                               var->blue.offset        = 0;
-                       } else {
-                               var->red.offset         = 0;
-                               var->green.offset       = 8;
-                               var->blue.offset        = 16;
-                       }
                        break;
                }
        default:
@@ -168,6 +155,23 @@ clcdfb_set_bitfields(struct clcd_fb *fb, struct fb_var_screeninfo *var)
                break;
        }
 
+       /*
+        * >= 16bpp displays have separate colour component bitfields
+        * encoded in the pixel data.  Calculate their position from
+        * the bitfield length defined above.
+        */
+       if (ret == 0 && var->bits_per_pixel >= 16) {
+               if (fb->panel->cntl & CNTL_BGR) {
+                       var->blue.offset = 0;
+                       var->green.offset = var->blue.offset + var->blue.length;
+                       var->red.offset = var->green.offset + var->green.length;
+               } else {
+                       var->red.offset = 0;
+                       var->green.offset = var->red.offset + var->red.length;
+                       var->blue.offset = var->green.offset + var->green.length;
+               }
+       }
+
        return ret;
 }