[PATCH] MMC: Flush mmc workqueue late in the boot sequence

[Haavard Skinnemoen <hskinnemoen@atmel.com>]

At some point before 2.6.20, the mmc subsystem moved the card
detection code to its own workqueue. One consequence of this change
is that when using an mmc card as a root device, the card may get
detected after the init task attempts to mount the root filesystem,
causing a kernel panic because the root device could not be opened.

This patch adds a call to mmc_flush_scheduled_work() late in the boot
sequence so that we can be sure the mmc card detection scans are
complete before attempting to use an mmc device as a root device.

Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
---
 drivers/mmc/core/sysfs.c |   13 +++++++++++++
 1 files changed, 13 insertions(+), 0 deletions(-)

diff --git a/drivers/mmc/core/sysfs.c b/drivers/mmc/core/sysfs.c
index 843b1fb..168b20f 100644
--- a/drivers/mmc/core/sysfs.c
+++ b/drivers/mmc/core/sysfs.c
@@ -358,3 +358,16 @@ static void __exit mmc_exit(void)
 
 module_init(mmc_init);
 module_exit(mmc_exit);
+
+#ifndef MODULE
+/*
+ * Make sure scanning for new cards has completed before attempting
+ * to mount the root filesystem.
+ */
+static int __init mmc_finish_detect(void)
+{
+	mmc_flush_scheduled_work();
+	return 0;
+}
+late_initcall(mmc_finish_detect);
+#endif
-- 
1.4.4.4

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