[PATCH 3/3] MMC: add checking of r/w command response

Russell King - ARM Linux
2011-06-20T19:10:57Z

Check the status bits in the r/w command response for any errors.
If error bits are set, then we won't have seen any data transferred,
so its pointless doing any further checking.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
---
drivers/mmc/card/block.c | 26 +++++++++++++++++++++++++-
1 files changed, 25 insertions(+), 1 deletions(-)

diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c
index aa074c8..e5d1c8a 100644
--- a/drivers/mmc/card/block.c
+++ b/drivers/mmc/card/block.c
@@ -812,6 +812,14 @@ static inline void mmc_apply_rel_rw(struct mmc_blk_request *brq,
}
}

+#define CMD_ERRORS \
+ (R1_OUT_OF_RANGE | /* Command argument out of range */ \
+ R1_ADDRESS_ERROR | /* Misaligned address */ \
+ R1_BLOCK_LEN_ERROR | /* Transferred block length incorrect */\
+ R1_WP_VIOLATION | /* Tried to write to protected block */ \
+ R1_CC_ERROR | /* Card controller error */ \
+ R1_ERROR) /* General/unknown error */
+
static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct request *req)
{
struct mmc_blk_data *md = mq->data;
@@ -967,6 +975,22 @@ static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct request *req)
}
}

+ /*
+ * Check for errors relating to the execution of the
+ * initial command - such as address errors. No data
+ * has been transferred.
+ */
+ if (brq.cmd.resp[0] & CMD_ERRORS) {
+ pr_err("%s: r/w command failed, status = %#x\n",
+ req->rq_disk->disk_name, brq.cmd.resp[0]);
+ goto cmd_abort;
+ }
+
+ /*
+ * Everything else is either success, or a data error of some
+ * kind. If it was a write, we may have transitioned to
+ * program mode, which we have to wait for it to complete.
+ */
if (!mmc_host_is_spi(card->host) && rq_data_dir(req) != READ) {
u32 status;
do {
@@ -986,7 +1010,7 @@ static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct request *req)
}

if (brq.data.error) {
- pr_err("%s: error %d transferring data, sector %u nr %u, cmd response %#x card status %#x\n",
+ pr_err("%s: error %d transferring data, sector %u, nr %u, cmd response %#x, card status %#x\n",
req->rq_disk->disk_name, brq.data.error,
(unsigned)blk_rq_pos(req),
(unsigned)blk_rq_sectors(req),
--
1.7.4.4