From: Russell King <rmk@dyn-67.arm.linux.org.uk>
Date: Sun, 24 Sep 2006 09:46:43 +0000 (+0100)
Subject: [MMC] Don't check READY_FOR_DATA when reading
X-Git-Tag: v2.6.19-rc1~886^2
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=2ed6d22cec37d9a3df4c5bacf1160dee7700106e;p=linux-2.6

[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>
---

diff --git a/drivers/mmc/mmc_block.c b/drivers/mmc/mmc_block.c
index 8d18b87bfd..db0e8ad439 100644
--- a/drivers/mmc/mmc_block.c
+++ b/drivers/mmc/mmc_block.c
@@ -231,27 +231,29 @@ static int mmc_blk_issue_rq(struct mmc_queue *mq, struct request *req)
 			goto cmd_err;
 		}
 
-		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);
-			if (err) {
-				printk(KERN_ERR "%s: error %d requesting status\n",
-				       req->rq_disk->disk_name, err);
-				goto cmd_err;
-			}
-		} while (!(cmd.resp[0] & R1_READY_FOR_DATA));
+		if (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);
+				if (err) {
+					printk(KERN_ERR "%s: error %d requesting status\n",
+					       req->rq_disk->disk_name, err);
+					goto cmd_err;
+				}
+			} while (!(cmd.resp[0] & R1_READY_FOR_DATA));
 
 #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;
+			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
+		}
 
 		/*
 		 * A block was successfully transferred.