[PATCH 1/3] MMC: allow get_card_status() to return error status

Russell King - ARM Linux
2011-06-20T19:10:08Z

If the MMC_SEND_STATUS command is not successful, we should not return
a zero status word, but instead allow the caller to know positively
that an error occurred.

Convert the open-coded get_card_status() to use the helper function,
and provide definitions for the card state field.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
---
drivers/mmc/card/block.c | 33 +++++++++------------------------
include/linux/mmc/mmc.h | 10 ++++++++++
2 files changed, 19 insertions(+), 24 deletions(-)

diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c
index 71da564..022edc3 100644
--- a/drivers/mmc/card/block.c
+++ b/drivers/mmc/card/block.c
@@ -525,7 +525,7 @@ static u32 mmc_sd_num_wr_blocks(struct mmc_card *card)
return result;
}

-static u32 get_card_status(struct mmc_card *card, struct request *req)
+static int get_card_status(struct mmc_card *card, u32 *status, int retries)
{
struct mmc_command cmd = {0};
int err;
@@ -534,11 +534,10 @@ static u32 get_card_status(struct mmc_card *card, struct request *req)
if (!mmc_host_is_spi(card->host))
cmd.arg = card->rca << 16;
cmd.flags = MMC_RSP_SPI_R2 | MMC_RSP_R1 | MMC_CMD_AC;
- err = mmc_wait_for_cmd(card->host, &cmd, 0);
- if (err)
- printk(KERN_ERR "%s: error %d sending status command",
- req->rq_disk->disk_name, err);
- return cmd.resp[0];
+ err = mmc_wait_for_cmd(card->host, &cmd, retries);
+ if (err == 0)
+ *status = cmd.resp[0];
+ return err;
}

static int mmc_blk_issue_discard_rq(struct mmc_queue *mq, struct request *req)
@@ -686,7 +685,6 @@ static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct request *req)
(md->flags & MMC_BLK_REL_WR);

do {
- struct mmc_command cmd = {0};
u32 readcmd, writecmd, status = 0;

memset(&brq, 0, sizeof(struct mmc_blk_request));
@@ -817,7 +815,7 @@ static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct request *req)
disable_multi = 1;
continue;
}
- status = get_card_status(card, req);
+ get_card_status(card, &status, 0);
}

if (brq.sbc.error) {
@@ -854,12 +852,7 @@ static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct request *req)

if (!mmc_host_is_spi(card->host) && rq_data_dir(req) != READ) {
do {
- int err;
-
- cmd.opcode = MMC_SEND_STATUS;
- cmd.arg = card->rca << 16;
- cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
- err = mmc_wait_for_cmd(card->host, &cmd, 5);
+ int err = get_card_status(card, &status, 5);
if (err) {
printk(KERN_ERR "%s: error %d requesting status\n",
req->rq_disk->disk_name, err);
@@ -870,16 +863,8 @@ static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct request *req)
* so make sure to check both the busy
* indication and the card state.
*/
- } while (!(cmd.resp[0] & R1_READY_FOR_DATA) ||
- (R1_CURRENT_STATE(cmd.resp[0]) == 7));
-
-#if 0
- if (cmd.resp[0] & ~0x00000900)
- printk(KERN_ERR "%s: status = %08x\n",
- req->rq_disk->disk_name, cmd.resp[0]);
- if (mmc_decode_status(cmd.resp))
- goto cmd_err;
-#endif
+ } while (!(status & R1_READY_FOR_DATA) ||
+ (R1_CURRENT_STATE(status) == R1_STATE_PRG));
}

if (brq.cmd.error || brq.stop.error || brq.data.error) {
diff --git a/include/linux/mmc/mmc.h b/include/linux/mmc/mmc.h
index ac26a68..8e425ab 100644
--- a/include/linux/mmc/mmc.h
+++ b/include/linux/mmc/mmc.h
@@ -140,6 +140,16 @@ static inline bool mmc_op_multi(u32 opcode)
#define R1_SWITCH_ERROR (1 << 7) /* sx, c */
#define R1_APP_CMD (1 << 5) /* sr, c */

+#define R1_STATE_IDLE 0
+#define R1_STATE_READY 1
+#define R1_STATE_IDENT 2
+#define R1_STATE_STBY 3
+#define R1_STATE_TRAN 4
+#define R1_STATE_DATA 5
+#define R1_STATE_RCV 6
+#define R1_STATE_PRG 7
+#define R1_STATE_DIS 8
+
/*
* MMC/SD in SPI mode reports R1 status always, and R2 for SEND_STATUS
* R1 is the low order byte; R2 is the next highest byte, when present.
--
1.7.4.4