[PATCH] libata: reimplement per-dev PM

Reimplement per-dev PM.  The original implementation directly put the
device into suspended mode and didn't synchronize w/ EH operations
including hotplug.  This patch reimplements ata_scsi_device_suspend()
and ata_scsi_device_resume() such that they request EH to perform the
respective operations.  Both functions synchronize with hotplug such
that it doesn't operate on detached devices.

Suspend waits for completion but resume just issues request and
returns.  This allows parallel wake up of devices and thus speeds up
system resume.

Due to sdev detach synchronization, it's not feasible to separate out
EH requesting from sdev handling; thus, ata_device_suspend/resume()
are removed and everything is implemented in the respective
libata-scsi functions.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

1 files changed, 0 insertions, 84 deletions

diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index ad5cac7..51dbc52 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -5009,88 +5009,6 @@ int ata_flush_cache(struct ata_device *dev)
 	return 0;
 }
 
-static int ata_standby_drive(struct ata_device *dev)
-{
-	unsigned int err_mask;
-
-	err_mask = ata_do_simple_cmd(dev, ATA_CMD_STANDBYNOW1);
-	if (err_mask) {
-		ata_dev_printk(dev, KERN_ERR, "failed to standby drive "
-			       "(err_mask=0x%x)\n", err_mask);
-		return -EIO;
-	}
-
-	return 0;
-}
-
-static int ata_start_drive(struct ata_device *dev)
-{
-	unsigned int err_mask;
-
-	err_mask = ata_do_simple_cmd(dev, ATA_CMD_IDLEIMMEDIATE);
-	if (err_mask) {
-		ata_dev_printk(dev, KERN_ERR, "failed to start drive "
-			       "(err_mask=0x%x)\n", err_mask);
-		return -EIO;
-	}
-
-	return 0;
-}
-
-/**
- *	ata_device_resume - wakeup a previously suspended devices
- *	@dev: the device to resume
- *
- *	Kick the drive back into action, by sending it an idle immediate
- *	command and making sure its transfer mode matches between drive
- *	and host.
- *
- */
-int ata_device_resume(struct ata_device *dev)
-{
-	struct ata_port *ap = dev->ap;
-
-	if (ap->pflags & ATA_PFLAG_SUSPENDED) {
-		struct ata_device *failed_dev;
-
-		ata_busy_sleep(ap, ATA_TMOUT_BOOT_QUICK, ATA_TMOUT_BOOT);
-		ata_busy_wait(ap, ATA_BUSY | ATA_DRQ, 200000);
-
-		ap->pflags &= ~ATA_PFLAG_SUSPENDED;
-		while (ata_set_mode(ap, &failed_dev))
-			ata_dev_disable(failed_dev);
-	}
-	if (!ata_dev_enabled(dev))
-		return 0;
-	if (dev->class == ATA_DEV_ATA)
-		ata_start_drive(dev);
-
-	return 0;
-}
-
-/**
- *	ata_device_suspend - prepare a device for suspend
- *	@dev: the device to suspend
- *	@state: target power management state
- *
- *	Flush the cache on the drive, if appropriate, then issue a
- *	standbynow command.
- */
-int ata_device_suspend(struct ata_device *dev, pm_message_t state)
-{
-	struct ata_port *ap = dev->ap;
-
-	if (!ata_dev_enabled(dev))
-		return 0;
-	if (dev->class == ATA_DEV_ATA)
-		ata_flush_cache(dev);
-
-	if (state.event != PM_EVENT_FREEZE)
-		ata_standby_drive(dev);
-	ap->pflags |= ATA_PFLAG_SUSPENDED;
-	return 0;
-}
-
 /**
  *	ata_port_start - Set port up for dma.
  *	@ap: Port to initialize
@@ -5946,8 +5864,6 @@ EXPORT_SYMBOL_GPL(ata_pci_default_filter);
 EXPORT_SYMBOL_GPL(ata_pci_clear_simplex);
 #endif /* CONFIG_PCI */
 
-EXPORT_SYMBOL_GPL(ata_device_suspend);
-EXPORT_SYMBOL_GPL(ata_device_resume);
 EXPORT_SYMBOL_GPL(ata_scsi_device_suspend);
 EXPORT_SYMBOL_GPL(ata_scsi_device_resume);