fbdev: consolidate common drawing functions into a header file

Consolidate common drawing functions into a single header file.

Signed-off-by: Antonino Daplas <adaplas@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 72 insertions, 0 deletions

diff --git a/drivers/video/fb_draw.h b/drivers/video/fb_draw.h
new file mode 100644
index 0000000..c5c4520
--- /dev/null
+++ b/drivers/video/fb_draw.h
@@ -0,0 +1,72 @@
+#ifndef _FB_DRAW_H
+#define _FB_DRAW_H
+
+#include <asm/types.h>
+
+    /*
+     *  Compose two values, using a bitmask as decision value
+     *  This is equivalent to (a & mask) | (b & ~mask)
+     */
+
+static inline unsigned long
+comp(unsigned long a, unsigned long b, unsigned long mask)
+{
+    return ((a ^ b) & mask) ^ b;
+}
+
+    /*
+     *  Create a pattern with the given pixel's color
+     */
+
+#if BITS_PER_LONG == 64
+static inline unsigned long
+pixel_to_pat( u32 bpp, u32 pixel)
+{
+	switch (bpp) {
+	case 1:
+		return 0xfffffffffffffffful*pixel;
+	case 2:
+		return 0x5555555555555555ul*pixel;
+	case 4:
+		return 0x1111111111111111ul*pixel;
+	case 8:
+		return 0x0101010101010101ul*pixel;
+	case 12:
+		return 0x0001001001001001ul*pixel;
+	case 16:
+		return 0x0001000100010001ul*pixel;
+	case 24:
+		return 0x0000000001000001ul*pixel;
+	case 32:
+		return 0x0000000100000001ul*pixel;
+	default:
+		panic("pixel_to_pat(): unsupported pixelformat\n");
+    }
+}
+#else
+static inline unsigned long
+pixel_to_pat( u32 bpp, u32 pixel)
+{
+	switch (bpp) {
+	case 1:
+		return 0xfffffffful*pixel;
+	case 2:
+		return 0x55555555ul*pixel;
+	case 4:
+		return 0x11111111ul*pixel;
+	case 8:
+		return 0x01010101ul*pixel;
+	case 12:
+		return 0x00001001ul*pixel;
+	case 16:
+		return 0x00010001ul*pixel;
+	case 24:
+		return 0x00000001ul*pixel;
+	case 32:
+		return 0x00000001ul*pixel;
+	default:
+		panic("pixel_to_pat(): unsupported pixelformat\n");
+    }
+}
+#endif
+#endif /* FB_DRAW_H */