[PATCH] fbdev: Add generic ddc read functionality

Adds functionality to read the EDID information over the DDC bus in a generic
way.  This code is based on the DDC implementation in the radeon driver.

[adaplas]
- separate from fbmon.c and place in new file fb_ddc.c
- remove dependency to CONFIG_I2C and CONFIG_I2C_ALGOBIT, otherwise, feature
  will not compile if i2c support is compiled as a module
- feature is selectable only by drivers needing it. It must have a
  'select FB_DDC if xxx' in Kconfig
- change printk's to dev_*, the i2c people prefers it

Signed-off-by: Dennis Munsie <dmunsie@cecropia.com>
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

include/linux/fb.h

@@ -2,6 +2,7 @@
 #define _LINUX_FB_H
 
 #include <asm/types.h>
+#include <linux/i2c.h>
 
 /* Definitions of frame buffers						*/
 
@@ -940,6 +941,7 @@ extern void fb_edid_to_monspecs(unsigned char *edid,
 				struct fb_monspecs *specs);
 extern void fb_destroy_modedb(struct fb_videomode *modedb);
 extern int fb_find_mode_cvt(struct fb_videomode *mode, int margins, int rb);
+extern unsigned char *fb_ddc_read(struct i2c_adapter *adapter);
 
 /* drivers/video/modedb.c */
 #define VESA_MODEDB_SIZE 34