[MMC] Don't check READY_FOR_DATA when reading

There's no point checking to see if the card is ready to accept
data when we're reading from it - sending the command only wastes
precious bus bandwidth.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

drivers/mmc/mmc_block.c

@@ -231,6 +231,7 @@ static int mmc_blk_issue_rq(struct mmc_queue *mq, struct request *req)
 			goto cmd_err;
 		}
 
+		if (rq_data_dir(req) != READ) {
 			do {
 				int err;
 
@@ -252,6 +253,7 @@ static int mmc_blk_issue_rq(struct mmc_queue *mq, struct request *req)
 			if (mmc_decode_status(cmd.resp))
 				goto cmd_err;
 #endif
+		}
 
 		/*
 		 * A block was successfully transferred.