Merge branch 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...
[linux-2.6] / drivers / ide / ide-park.c
1 #include <linux/kernel.h>
2 #include <linux/ide.h>
3 #include <linux/jiffies.h>
4 #include <linux/blkdev.h>
5
6 DECLARE_WAIT_QUEUE_HEAD(ide_park_wq);
7
8 static void issue_park_cmd(ide_drive_t *drive, unsigned long timeout)
9 {
10         ide_hwif_t *hwif = drive->hwif;
11         struct request_queue *q = drive->queue;
12         struct request *rq;
13         int rc;
14
15         timeout += jiffies;
16         spin_lock_irq(&hwif->lock);
17         if (drive->dev_flags & IDE_DFLAG_PARKED) {
18                 int reset_timer = time_before(timeout, drive->sleep);
19                 int start_queue = 0;
20
21                 drive->sleep = timeout;
22                 wake_up_all(&ide_park_wq);
23                 if (reset_timer && del_timer(&hwif->timer))
24                         start_queue = 1;
25                 spin_unlock_irq(&hwif->lock);
26
27                 if (start_queue) {
28                         spin_lock_irq(q->queue_lock);
29                         blk_start_queueing(q);
30                         spin_unlock_irq(q->queue_lock);
31                 }
32                 return;
33         }
34         spin_unlock_irq(&hwif->lock);
35
36         rq = blk_get_request(q, READ, __GFP_WAIT);
37         rq->cmd[0] = REQ_PARK_HEADS;
38         rq->cmd_len = 1;
39         rq->cmd_type = REQ_TYPE_SPECIAL;
40         rq->special = &timeout;
41         rc = blk_execute_rq(q, NULL, rq, 1);
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, READ, GFP_NOWAIT);
51         if (unlikely(!rq))
52                 goto out;
53
54         rq->cmd[0] = REQ_UNPARK_HEADS;
55         rq->cmd_len = 1;
56         rq->cmd_type = REQ_TYPE_SPECIAL;
57         elv_add_request(q, rq, ELEVATOR_INSERT_FRONT, 1);
58
59 out:
60         return;
61 }
62
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 (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
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
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 = strict_strtol(buf, 10, &input);
122         if (rc || input < -2)
123                 return -EINVAL;
124         if (input > MAX_PARK_TIMEOUT) {
125                 input = MAX_PARK_TIMEOUT;
126                 rc = -EOVERFLOW;
127         }
128
129         mutex_lock(&ide_setting_mtx);
130         if (input >= 0) {
131                 if (drive->dev_flags & IDE_DFLAG_NO_UNLOAD)
132                         rc = -EOPNOTSUPP;
133                 else if (input || drive->dev_flags & IDE_DFLAG_PARKED)
134                         issue_park_cmd(drive, msecs_to_jiffies(input));
135         } else {
136                 if (drive->media == ide_disk)
137                         switch (input) {
138                         case -1:
139                                 drive->dev_flags &= ~IDE_DFLAG_NO_UNLOAD;
140                                 break;
141                         case -2:
142                                 drive->dev_flags |= IDE_DFLAG_NO_UNLOAD;
143                                 break;
144                         }
145                 else
146                         rc = -EOPNOTSUPP;
147         }
148         mutex_unlock(&ide_setting_mtx);
149
150         return rc ? rc : len;
151 }