1 files changed, 121 insertions, 0 deletions
diff --git a/drivers/ide/ide-park.c b/drivers/ide/ide-park.c
new file mode 100644
index 0000000..03b00e5
--- /dev/null
+++ b/drivers/ide/ide-park.c
@@ -0,0 +1,121 @@
+#include <linux/kernel.h>
+#include <linux/ide.h>
+#include <linux/jiffies.h>
+#include <linux/blkdev.h>
+
+DECLARE_WAIT_QUEUE_HEAD(ide_park_wq);
+
+static void issue_park_cmd(ide_drive_t *drive, unsigned long timeout)
+{
+	struct request_queue *q = drive->queue;
+	struct request *rq;
+	int rc;
+
+	timeout += jiffies;
+	spin_lock_irq(&ide_lock);
+	if (drive->dev_flags & IDE_DFLAG_PARKED) {
+		ide_hwgroup_t *hwgroup = drive->hwif->hwgroup;
+		int reset_timer;
+
+		reset_timer = time_before(timeout, drive->sleep);
+		drive->sleep = timeout;
+		wake_up_all(&ide_park_wq);
+		if (reset_timer && hwgroup->sleeping &&
+		    del_timer(&hwgroup->timer)) {
+			hwgroup->sleeping = 0;
+			hwgroup->busy = 0;
+			blk_start_queueing(q);
+		}
+		spin_unlock_irq(&ide_lock);
+		return;
+	}
+	spin_unlock_irq(&ide_lock);
+
+	rq = blk_get_request(q, READ, __GFP_WAIT);
+	rq->cmd[0] = REQ_PARK_HEADS;
+	rq->cmd_len = 1;
+	rq->cmd_type = REQ_TYPE_SPECIAL;
+	rq->special = &timeout;
+	rc = blk_execute_rq(q, NULL, rq, 1);
+	blk_put_request(rq);
+	if (rc)
+		goto out;
+
+	/*
+	 * Make sure that *some* command is sent to the drive after the
+	 * timeout has expired, so power management will be reenabled.
+	 */
+	rq = blk_get_request(q, READ, GFP_NOWAIT);
+	if (unlikely(!rq))
+		goto out;
+
+	rq->cmd[0] = REQ_UNPARK_HEADS;
+	rq->cmd_len = 1;
+	rq->cmd_type = REQ_TYPE_SPECIAL;
+	elv_add_request(q, rq, ELEVATOR_INSERT_FRONT, 1);
+
+out:
+	return;
+}
+
+ssize_t ide_park_show(struct device *dev, struct device_attribute *attr,
+		      char *buf)
+{
+	ide_drive_t *drive = to_ide_device(dev);
+	unsigned long now;
+	unsigned int msecs;
+
+	if (drive->dev_flags & IDE_DFLAG_NO_UNLOAD)
+		return -EOPNOTSUPP;
+
+	spin_lock_irq(&ide_lock);
+	now = jiffies;
+	if (drive->dev_flags & IDE_DFLAG_PARKED &&
+	    time_after(drive->sleep, now))
+		msecs = jiffies_to_msecs(drive->sleep - now);
+	else
+		msecs = 0;
+	spin_unlock_irq(&ide_lock);
+
+	return snprintf(buf, 20, "%u\n", msecs);
+}
+
+ssize_t ide_park_store(struct device *dev, struct device_attribute *attr,
+		       const char *buf, size_t len)
+{
+#define MAX_PARK_TIMEOUT 30000
+	ide_drive_t *drive = to_ide_device(dev);
+	long int input;
+	int rc;
+
+	rc = strict_strtol(buf, 10, &input);
+	if (rc || input < -2)
+		return -EINVAL;
+	if (input > MAX_PARK_TIMEOUT) {
+		input = MAX_PARK_TIMEOUT;
+		rc = -EOVERFLOW;
+	}
+
+	mutex_lock(&ide_setting_mtx);
+	if (input >= 0) {
+		if (drive->dev_flags & IDE_DFLAG_NO_UNLOAD)
+			rc = -EOPNOTSUPP;
+		else if (input || drive->dev_flags & IDE_DFLAG_PARKED)
+			issue_park_cmd(drive, msecs_to_jiffies(input));
+	} else {
+		if (drive->media == ide_disk)
+			switch (input) {
+			case -1:
+				drive->dev_flags &= ~IDE_DFLAG_NO_UNLOAD;
+				break;
+			case -2:
+				drive->dev_flags |= IDE_DFLAG_NO_UNLOAD;
+				break;
+			}
+		else
+			rc = -EOPNOTSUPP;
+	}
+	mutex_unlock(&ide_setting_mtx);
+
+	return rc ? rc : len;
+}