ide-cd: clear sense buffer before issuing request sense

Impact: code simplification

ide_cd_request_sense_fixup() clears the tail of the sense buffer if
the device didn't completely fill it.  This patch makes
cdrom_queue_request_sense() clear the sense buffer before issuing the
command instead of clearing it afterwards.  This simplifies code and
eases future changes.
Signed-off-by: NTejun Heo <tj@kernel.org>

drivers/ide/ide-cd.c

@@ -217,6 +217,8 @@ static void cdrom_queue_request_sense(ide_drive_t *drive, void *sense,
 	if (sense == NULL)
 		sense = &info->sense_data;
 
+	memset(sense, 0, 18);
+
 	/* stuff the sense request in front of our current request */
 	blk_rq_init(NULL, rq);
 	rq->cmd_type = REQ_TYPE_ATA_PC;
@@ -504,14 +506,8 @@ static void ide_cd_request_sense_fixup(ide_drive_t *drive, struct ide_cmd *cmd)
 	 * and some drives don't send them.  Sigh.
 	 */
 	if (rq->cmd[0] == GPCMD_REQUEST_SENSE &&
-	    cmd->nleft > 0 && cmd->nleft <= 5) {
-		unsigned int ofs = cmd->nbytes - cmd->nleft;
-
-		while (cmd->nleft > 0) {
-			*((u8 *)rq->data + ofs++) = 0;
-			cmd->nleft--;
-		}
-	}
+	    cmd->nleft > 0 && cmd->nleft <= 5)
+		cmd->nleft = 0;
 }
 
 int ide_cd_queue_pc(ide_drive_t *drive, const unsigned char *cmd,