mmc: mmc: Fix partition switch timeout for some eMMCs

[linux-2.6-block.git] / drivers / mmc / core / mmc.c

diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index 35873d4cc4426e52a19130040be6571bad096a73..b81b08f81325721037362213997618b7ebfc1e10 100644 (file)
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -333,6 +333,9 @@ static void mmc_manage_gp_partitions(struct mmc_card *card, u8 *ext_csd)
        }
 }
 
+/* Minimum partition switch timeout in milliseconds */
+#define MMC_MIN_PART_SWITCH_TIME       300
+
 /*
  * Decode extended CSD.
  */
@@ -397,6 +400,10 @@ static int mmc_decode_ext_csd(struct mmc_card *card, u8 *ext_csd)
 
                /* EXT_CSD value is in units of 10ms, but we store in ms */
                card->ext_csd.part_time = 10 * ext_csd[EXT_CSD_PART_SWITCH_TIME];
+               /* Some eMMC set the value too low so set a minimum */
+               if (card->ext_csd.part_time &&
+                   card->ext_csd.part_time < MMC_MIN_PART_SWITCH_TIME)
+                       card->ext_csd.part_time = MMC_MIN_PART_SWITCH_TIME;
 
                /* Sleep / awake timeout in 100ns units */
                if (sa_shift > 0 && sa_shift <= 0x17)