sdio: add CD disable support

Add support to disconnect the pull-up resistor on CD/DAT[3] (pin 1)
of the card. This may be desired on certain setups of boards,
controllers and embedded sdio devices which do not need the card's
pull-up. As a result, card detection is disabled and power is saved.

[akpm@linux-foundation.org: simplify sdio_disable_cd() a bit]
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Acked-by: Matt Fleming <matt@console-pimps.org>
Cc: Ian Molton <ian@mnementh.co.uk>
Cc: "Roberto A. Foglietta" <roberto.foglietta@gmail.com>
Cc: Philip Langdale <philipl@overt.org>
Cc: Pierre Ossman <pierre@ossman.eu>
Cc: David Vrabel <david.vrabel@csr.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 2 insertions, 1 deletions

diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h
index 58f59174c64b..00db39cceadc 100644
--- a/include/linux/mmc/card.h
+++ b/include/linux/mmc/card.h
@@ -64,7 +64,8 @@ struct sdio_cccr {
                                 low_speed:1,
                                 wide_bus:1,
                                 high_power:1,
-                                high_speed:1;
+                                high_speed:1,
+                                disable_cd:1;
 };
 
 struct sdio_cis {