MMC fix for 2.6.38

From: Chris Ball
Date: Mon Mar 07 2011 - 18:05:58 EST


Linus,

Please pull from:

git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc.git for-linus

to fix an SDIO initialization regression introduced in -rc1. Thanks.

The following changes since commit 214d93b02c4fe93638ad268613c9702a81ed9192:
Linus Torvalds (1):
Merge branch 'omap-fixes-for-linus' of git://git.kernel.org/.../tmlind/linux-omap-2.6

are available in the git repository at:

git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc.git for-linus

Dmitry Shmidt (1):
mmc: sdio: Allow sdio operations in other threads during sdio_add_func()

drivers/mmc/core/sdio.c | 3 +--
1 files changed, 1 insertions(+), 2 deletions(-)

From: Dmitry Shmidt <dimitrysh@xxxxxxxxxx>
Date: Thu, 3 Mar 2011 17:40:10 -0500
Subject: [PATCH] mmc: sdio: Allow sdio operations in other threads during sdio_add_func()

This fixes a bug introduced by 807e8e40673d ("mmc: Fix sd/sdio/mmc
initialization frequency retries") that prevented SDIO drivers from
performing SDIO commands in their probe routines -- the above patch
called mmc_claim_host() before sdio_add_func(), which causes a deadlock
if an external SDIO driver calls sdio_claim_host().

Fix tested on an OLPC XO-1.75 with libertas on SDIO.

Signed-off-by: Dmitry Shmidt <dimitrysh@xxxxxxxxxx>
Reviewed-and-Tested-by: Chris Ball <cjb@xxxxxxxxxx>
Signed-off-by: Chris Ball <cjb@xxxxxxxxxx>
---
drivers/mmc/core/sdio.c | 3 +--
1 files changed, 1 insertions(+), 2 deletions(-)

diff --git a/drivers/mmc/core/sdio.c b/drivers/mmc/core/sdio.c
index 5c4a54d..ebc62ad 100644
--- a/drivers/mmc/core/sdio.c
+++ b/drivers/mmc/core/sdio.c
@@ -792,7 +792,6 @@ int mmc_attach_sdio(struct mmc_host *host)
*/
mmc_release_host(host);
err = mmc_add_card(host->card);
- mmc_claim_host(host);
if (err)
goto remove_added;

@@ -805,12 +804,12 @@ int mmc_attach_sdio(struct mmc_host *host)
goto remove_added;
}

+ mmc_claim_host(host);
return 0;


remove_added:
/* Remove without lock if the device has been added. */
- mmc_release_host(host);
mmc_sdio_remove(host);
mmc_claim_host(host);
remove:
--
Chris Ball <cjb@xxxxxxxxxx> <http://printf.net/>
One Laptop Per Child
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