This patch fixes the issue that mmc_blk_issue_rq still
flushes cache when eMMC cache has already been off
through user space tool, such as mmc-utils.
The reason is that card->ext_csd.cache_ctrl isn't reset.
Signed-off-by: beanhuo <bean...@micron.com>
---
drivers/mmc/core/block.c | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c
index 1621fa0..fb3635ac 100644
--- a/drivers/mmc/core/block.c
+++ b/drivers/mmc/core/block.c
@@ -64,6 +64,7 @@ MODULE_ALIAS("mmc:block");
#define MMC_BLK_TIMEOUT_MS (10 * 60 * 1000) /* 10 minute timeout */
#define MMC_SANITIZE_REQ_TIMEOUT 240000
#define MMC_EXTRACT_INDEX_FROM_ARG(x) ((x & 0x00FF0000) >> 16)
+#define MMC_EXTRACT_VALUE_FROM_ARG(x) ((x & 0x0000FF00) >> 8)
#define mmc_req_rel_wr(req) ((req->cmd_flags & REQ_FUA) && \
(rq_data_dir(req) == WRITE))
@@ -535,6 +536,14 @@ static int __mmc_blk_ioctl_cmd(struct mmc_card *card,
struct mmc_blk_data *md,
return data.error;
}
+ if ((MMC_EXTRACT_INDEX_FROM_ARG(cmd.arg) == EXT_CSD_CACHE_CTRL) &&
+ (cmd.opcode == MMC_SWITCH) && (card->ext_csd.cache_size > 0)) {
+ if (MMC_EXTRACT_VALUE_FROM_ARG(cmd.arg) & 1)
+ card->ext_csd.cache_ctrl = 1;
+ else
+ card->ext_csd.cache_ctrl = 0;
+ }
+
/*
* According to the SD specs, some commands require a delay after
* issuing the command.
--
2.7.4
