diff options
author | Zheng Da <zhengda1936@gmail.com> | 2010-05-31 12:41:21 +0200 |
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committer | Zheng Da <zhengda1936@gmail.com> | 2010-05-31 12:41:21 +0200 |
commit | b5b8ef16ea0e7517169d521c297784d5678d7518 (patch) | |
tree | 2e7d63329fe6ab07de6f972e39dd85ce74a69dde /windhoek/ide/ide-park.c | |
parent | 61cbf207a16ec76e4fefba4e5a3ad91c84dee447 (diff) |
check in the initial version of windhoek by DROPS.
Diffstat (limited to 'windhoek/ide/ide-park.c')
-rw-r--r-- | windhoek/ide/ide-park.c | 124 |
1 files changed, 124 insertions, 0 deletions
diff --git a/windhoek/ide/ide-park.c b/windhoek/ide/ide-park.c new file mode 100644 index 00000000..c875a957 --- /dev/null +++ b/windhoek/ide/ide-park.c @@ -0,0 +1,124 @@ +#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) +{ + 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) { + spin_lock_irq(q->queue_lock); + blk_start_queueing(q); + spin_unlock_irq(q->queue_lock); + } + 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; +} + +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; +} |