[U-Boot] [PATCH 4/6] mmc: Continue polling MMC card for OCR only if it is still not ready

[Andrew Gabbasov]

Some MMC cards come to ready state quite quickly, so that the respective
flag appears to be set in mmc_send_op_cond already. In this case trying
to continue polling the card with CMD1 in mmc_complete_op_cond is incorrect
and may lead to unpredictable results. So check the flag before polling
and skip it appropriately.

Signed-off-by: Andrew Gabbasov <andrew_gabbasov at mentor.com>
---
 drivers/mmc/mmc.c | 20 +++++++++++---------
 1 file changed, 11 insertions(+), 9 deletions(-)

diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
index d073d79..42af47c 100644
--- a/drivers/mmc/mmc.c
+++ b/drivers/mmc/mmc.c
@@ -403,15 +403,17 @@ static int mmc_complete_op_cond(struct mmc *mmc)
 	int err;
 
 	mmc->op_cond_pending = 0;
-	start = get_timer(0);
-	do {
-		err = mmc_send_op_cond_iter(mmc, 1);
-		if (err)
-			return err;
-		if (get_timer(start) > timeout)
-			return UNUSABLE_ERR;
-		udelay(100);
-	} while (!(mmc->ocr & OCR_BUSY));
+	if (!(mmc->ocr & OCR_BUSY)) {
+		start = get_timer(0);
+		do {
+			err = mmc_send_op_cond_iter(mmc, 1);
+			if (err)
+				return err;
+			if (get_timer(start) > timeout)
+				return UNUSABLE_ERR;
+			udelay(100);
+		} while (!(mmc->ocr & OCR_BUSY));
+	}
 
 	if (mmc_host_is_spi(mmc)) { /* read OCR for spi */
 		cmd.cmdidx = MMC_CMD_SPI_READ_OCR;
-- 
2.1.0