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 
8 DECLARE_WAIT_QUEUE_HEAD(ide_park_wq);
9 
issue_park_cmd(ide_drive_t * drive,unsigned long timeout)10 static 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_run_queue(q);
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 	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 	elv_add_request(q, rq, ELEVATOR_INSERT_FRONT);
58 
59 out:
60 	return;
61 }
62 
ide_do_park_unpark(ide_drive_t * drive,struct request * rq)63 ide_startstop_t ide_do_park_unpark(ide_drive_t *drive, struct request *rq)
64 {
65 	struct ide_cmd cmd;
66 	struct ide_taskfile *tf = &cmd.tf;
67 
68 	memset(&cmd, 0, sizeof(cmd));
69 	if (scsi_req(rq)->cmd[0] == REQ_PARK_HEADS) {
70 		drive->sleep = *(unsigned long *)rq->special;
71 		drive->dev_flags |= IDE_DFLAG_SLEEPING;
72 		tf->command = ATA_CMD_IDLEIMMEDIATE;
73 		tf->feature = 0x44;
74 		tf->lbal = 0x4c;
75 		tf->lbam = 0x4e;
76 		tf->lbah = 0x55;
77 		cmd.valid.out.tf = IDE_VALID_OUT_TF | IDE_VALID_DEVICE;
78 		cmd.valid.in.tf  = IDE_VALID_IN_TF  | IDE_VALID_DEVICE;
79 	} else		/* cmd == REQ_UNPARK_HEADS */
80 		tf->command = ATA_CMD_CHK_POWER;
81 
82 	cmd.tf_flags |= IDE_TFLAG_CUSTOM_HANDLER;
83 	cmd.protocol = ATA_PROT_NODATA;
84 
85 	cmd.rq = rq;
86 
87 	return do_rw_taskfile(drive, &cmd);
88 }
89 
ide_park_show(struct device * dev,struct device_attribute * attr,char * buf)90 ssize_t ide_park_show(struct device *dev, struct device_attribute *attr,
91 		      char *buf)
92 {
93 	ide_drive_t *drive = to_ide_device(dev);
94 	ide_hwif_t *hwif = drive->hwif;
95 	unsigned long now;
96 	unsigned int msecs;
97 
98 	if (drive->dev_flags & IDE_DFLAG_NO_UNLOAD)
99 		return -EOPNOTSUPP;
100 
101 	spin_lock_irq(&hwif->lock);
102 	now = jiffies;
103 	if (drive->dev_flags & IDE_DFLAG_PARKED &&
104 	    time_after(drive->sleep, now))
105 		msecs = jiffies_to_msecs(drive->sleep - now);
106 	else
107 		msecs = 0;
108 	spin_unlock_irq(&hwif->lock);
109 
110 	return snprintf(buf, 20, "%u\n", msecs);
111 }
112 
ide_park_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)113 ssize_t ide_park_store(struct device *dev, struct device_attribute *attr,
114 		       const char *buf, size_t len)
115 {
116 #define MAX_PARK_TIMEOUT 30000
117 	ide_drive_t *drive = to_ide_device(dev);
118 	long int input;
119 	int rc;
120 
121 	rc = kstrtol(buf, 10, &input);
122 	if (rc)
123 		return rc;
124 	if (input < -2)
125 		return -EINVAL;
126 	if (input > MAX_PARK_TIMEOUT) {
127 		input = MAX_PARK_TIMEOUT;
128 		rc = -EOVERFLOW;
129 	}
130 
131 	mutex_lock(&ide_setting_mtx);
132 	if (input >= 0) {
133 		if (drive->dev_flags & IDE_DFLAG_NO_UNLOAD)
134 			rc = -EOPNOTSUPP;
135 		else if (input || drive->dev_flags & IDE_DFLAG_PARKED)
136 			issue_park_cmd(drive, msecs_to_jiffies(input));
137 	} else {
138 		if (drive->media == ide_disk)
139 			switch (input) {
140 			case -1:
141 				drive->dev_flags &= ~IDE_DFLAG_NO_UNLOAD;
142 				break;
143 			case -2:
144 				drive->dev_flags |= IDE_DFLAG_NO_UNLOAD;
145 				break;
146 			}
147 		else
148 			rc = -EOPNOTSUPP;
149 	}
150 	mutex_unlock(&ide_setting_mtx);
151 
152 	return rc ? rc : len;
153 }
154