mmc: support unsafe resume of cards

Since many have the system root on MMC/SD we must allow some foot
shooting when it comes to resume.

We cannot detect if a card is removed and reinserted during suspend,
so the safe approach would be to assume it was, avoiding potential
filesystem corruption. This will of course not work if you cannot
release the card before suspend.

This commit adds a compile time option that makes the MMC layer
assume the card wasn't touched if it is redetected upon resume.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>

1 files changed, 2 insertions, 0 deletions

diff --git a/drivers/mmc/core/core.h b/drivers/mmc/core/core.h
index fad8edc38099..177264d090ac 100644
--- a/drivers/mmc/core/core.h
+++ b/drivers/mmc/core/core.h
@@ -18,6 +18,8 @@
 struct mmc_bus_ops {
         void (*remove)(struct mmc_host *);
         void (*detect)(struct mmc_host *);
+        void (*suspend)(struct mmc_host *);
+        void (*resume)(struct mmc_host *);
 };
 
 void mmc_attach_bus(struct mmc_host *host, const struct mmc_bus_ops *ops);