1// SPDX-License-Identifier: GPL-2.0
  2#include <linux/kernel.h>
  3#include <linux/gfp.h>
  4#include <linux/ide.h>
  5#include <linux/jiffies.h>
  6#include <linux/blkdev.h>
  7
  8DECLARE_WAIT_QUEUE_HEAD(ide_park_wq);
  9
 10static void issue_park_cmd(ide_drive_t *drive, unsigned long timeout)
 11{
 12	ide_hwif_t *hwif = drive->hwif;
 13	struct request_queue *q = drive->queue;
 14	struct request *rq;
 15	int rc;
 16
 17	timeout += jiffies;
 18	spin_lock_irq(&hwif->lock);
 19	if (drive->dev_flags & IDE_DFLAG_PARKED) {
 20		int reset_timer = time_before(timeout, drive->sleep);
 21		int start_queue = 0;
 22
 23		drive->sleep = timeout;
 24		wake_up_all(&ide_park_wq);
 25		if (reset_timer && del_timer(&hwif->timer))
 26			start_queue = 1;
 27		spin_unlock_irq(&hwif->lock);
 28
 29		if (start_queue)
 30			blk_mq_run_hw_queues(q, true);
 31		return;
 32	}
 33	spin_unlock_irq(&hwif->lock);
 34
 35	rq = blk_get_request(q, REQ_OP_DRV_IN, 0);
 36	scsi_req(rq)->cmd[0] = REQ_PARK_HEADS;
 37	scsi_req(rq)->cmd_len = 1;
 38	ide_req(rq)->type = ATA_PRIV_MISC;
 39	ide_req(rq)->special = &timeout;
 40	blk_execute_rq(q, NULL, rq, 1);
 41	rc = scsi_req(rq)->result ? -EIO : 0;
 42	blk_put_request(rq);
 43	if (rc)
 44		goto out;
 45
 46	/*
 47	 * Make sure that *some* command is sent to the drive after the
 48	 * timeout has expired, so power management will be reenabled.
 49	 */
 50	rq = blk_get_request(q, REQ_OP_DRV_IN, BLK_MQ_REQ_NOWAIT);
 51	if (IS_ERR(rq))
 52		goto out;
 53
 54	scsi_req(rq)->cmd[0] = REQ_UNPARK_HEADS;
 55	scsi_req(rq)->cmd_len = 1;
 56	ide_req(rq)->type = ATA_PRIV_MISC;
 57	spin_lock_irq(&hwif->lock);
 58	ide_insert_request_head(drive, rq);
 59	spin_unlock_irq(&hwif->lock);
 60
 61out:
 62	return;
 63}
 64
 65ide_startstop_t ide_do_park_unpark(ide_drive_t *drive, struct request *rq)
 66{
 67	struct ide_cmd cmd;
 68	struct ide_taskfile *tf = &cmd.tf;
 69
 70	memset(&cmd, 0, sizeof(cmd));
 71	if (scsi_req(rq)->cmd[0] == REQ_PARK_HEADS) {
 72		drive->sleep = *(unsigned long *)ide_req(rq)->special;
 73		drive->dev_flags |= IDE_DFLAG_SLEEPING;
 74		tf->command = ATA_CMD_IDLEIMMEDIATE;
 75		tf->feature = 0x44;
 76		tf->lbal = 0x4c;
 77		tf->lbam = 0x4e;
 78		tf->lbah = 0x55;
 79		cmd.valid.out.tf = IDE_VALID_OUT_TF | IDE_VALID_DEVICE;
 80		cmd.valid.in.tf  = IDE_VALID_IN_TF  | IDE_VALID_DEVICE;
 81	} else		/* cmd == REQ_UNPARK_HEADS */
 82		tf->command = ATA_CMD_CHK_POWER;
 83
 84	cmd.tf_flags |= IDE_TFLAG_CUSTOM_HANDLER;
 85	cmd.protocol = ATA_PROT_NODATA;
 86
 87	cmd.rq = rq;
 88
 89	return do_rw_taskfile(drive, &cmd);
 90}
 91
 92ssize_t ide_park_show(struct device *dev, struct device_attribute *attr,
 93		      char *buf)
 94{
 95	ide_drive_t *drive = to_ide_device(dev);
 96	ide_hwif_t *hwif = drive->hwif;
 97	unsigned long now;
 98	unsigned int msecs;
 99
100	if (drive->dev_flags & IDE_DFLAG_NO_UNLOAD)
101		return -EOPNOTSUPP;
102
103	spin_lock_irq(&hwif->lock);
104	now = jiffies;
105	if (drive->dev_flags & IDE_DFLAG_PARKED &&
106	    time_after(drive->sleep, now))
107		msecs = jiffies_to_msecs(drive->sleep - now);
108	else
109		msecs = 0;
110	spin_unlock_irq(&hwif->lock);
111
112	return snprintf(buf, 20, "%u\n", msecs);
113}
114
115ssize_t ide_park_store(struct device *dev, struct device_attribute *attr,
116		       const char *buf, size_t len)
117{
118#define MAX_PARK_TIMEOUT 30000
119	ide_drive_t *drive = to_ide_device(dev);
120	long int input;
121	int rc;
122
123	rc = kstrtol(buf, 10, &input);
124	if (rc)
125		return rc;
126	if (input < -2)
127		return -EINVAL;
128	if (input > MAX_PARK_TIMEOUT) {
129		input = MAX_PARK_TIMEOUT;
130		rc = -EOVERFLOW;
131	}
132
133	mutex_lock(&ide_setting_mtx);
134	if (input >= 0) {
135		if (drive->dev_flags & IDE_DFLAG_NO_UNLOAD)
136			rc = -EOPNOTSUPP;
137		else if (input || drive->dev_flags & IDE_DFLAG_PARKED)
138			issue_park_cmd(drive, msecs_to_jiffies(input));
139	} else {
140		if (drive->media == ide_disk)
141			switch (input) {
142			case -1:
143				drive->dev_flags &= ~IDE_DFLAG_NO_UNLOAD;
144				break;
145			case -2:
146				drive->dev_flags |= IDE_DFLAG_NO_UNLOAD;
147				break;
148			}
149		else
150			rc = -EOPNOTSUPP;
151	}
152	mutex_unlock(&ide_setting_mtx);
153
154	return rc ? rc : len;
155}