[MMC] Don't check READY_FOR_DATA when reading
authorRussell King <rmk@dyn-67.arm.linux.org.uk>
Sun, 24 Sep 2006 09:46:43 +0000 (10:46 +0100)
committerRussell King <rmk+kernel@arm.linux.org.uk>
Sun, 24 Sep 2006 09:46:43 +0000 (10:46 +0100)
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

index 8d18b87bfd342e702c0edd79a932c247ea938ed1..db0e8ad439a5f6c8e09f873bf5734d9bc51df217 100644 (file)
@@ -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.