fbdev: mm: Deferred IO support
This implements deferred IO support in fbdev. Deferred IO is a way to delay
and repurpose IO. This implementation is done using mm's page_mkwrite and
page_mkclean hooks in order to detect, delay and then rewrite IO. This
functionality is used by hecubafb.
[adaplas]
This is useful for graphics hardware with no directly addressable/mappable
framebuffer. Implementing this will allow the "framebuffer" to be accesible
from user space via mmap().
Signed-off-by: Jaya Kumar <jayakumar.lkml@gmail.com>
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>
diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
index 8dfa88a..61c0a03 100644
--- a/drivers/video/Kconfig
+++ b/drivers/video/Kconfig
@@ -91,6 +91,11 @@
blitting. This is used by drivers that don't provide their own
(accelerated) version.
+config FB_DEFERRED_IO
+ bool
+ depends on FB
+ default y
+
config FB_SVGALIB
tristate
depends on FB