linux-stable-rt/drivers/ide/ide-park.c

150 lines
3.5 KiB
C

#include <linux/kernel.h>
#include <linux/gfp.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)
{
ide_hwif_t *hwif = drive->hwif;
struct request_queue *q = drive->queue;
struct request *rq;
int rc;
timeout += jiffies;
spin_lock_irq(&hwif->lock);
if (drive->dev_flags & IDE_DFLAG_PARKED) {
int reset_timer = time_before(timeout, drive->sleep);
int start_queue = 0;
drive->sleep = timeout;
wake_up_all(&ide_park_wq);
if (reset_timer && del_timer(&hwif->timer))
start_queue = 1;
spin_unlock_irq(&hwif->lock);
if (start_queue)
blk_run_queue(q);
return;
}
spin_unlock_irq(&hwif->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;
}
ide_startstop_t ide_do_park_unpark(ide_drive_t *drive, struct request *rq)
{
struct ide_cmd cmd;
struct ide_taskfile *tf = &cmd.tf;
memset(&cmd, 0, sizeof(cmd));
if (rq->cmd[0] == REQ_PARK_HEADS) {
drive->sleep = *(unsigned long *)rq->special;
drive->dev_flags |= IDE_DFLAG_SLEEPING;
tf->command = ATA_CMD_IDLEIMMEDIATE;
tf->feature = 0x44;
tf->lbal = 0x4c;
tf->lbam = 0x4e;
tf->lbah = 0x55;
cmd.valid.out.tf = IDE_VALID_OUT_TF | IDE_VALID_DEVICE;
cmd.valid.in.tf = IDE_VALID_IN_TF | IDE_VALID_DEVICE;
} else /* cmd == REQ_UNPARK_HEADS */
tf->command = ATA_CMD_CHK_POWER;
cmd.tf_flags |= IDE_TFLAG_CUSTOM_HANDLER;
cmd.protocol = ATA_PROT_NODATA;
cmd.rq = rq;
return do_rw_taskfile(drive, &cmd);
}
ssize_t ide_park_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
ide_drive_t *drive = to_ide_device(dev);
ide_hwif_t *hwif = drive->hwif;
unsigned long now;
unsigned int msecs;
if (drive->dev_flags & IDE_DFLAG_NO_UNLOAD)
return -EOPNOTSUPP;
spin_lock_irq(&hwif->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(&hwif->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;
}