Currently, the device tree of ata port and scsi host looks as below,
/sys/devices/pci0000:00/0000:00:1f.2 (ahci controller)
|-- ata1 (ata port)
|-- host0 (scsi host)
|-- target0:0:0 (scsi target)
|-- 0:0:0:0 (disk)
This patch makes ata port as parent device of scsi host, then it becomes
/sys/devices/pci0000:00/0000:00:1f.2 (ahci controller)
|-- ata1 (ata port)
|-- host0 (scsi host)
|-- target0:0:0 (scsi target)
|-- 0:0:0:0 (disk)
With this change, the ata port runtime PM is easier.
For example, the ata port runtime suspend will happen as,
disk suspend --> scsi target suspend --> scsi host suspend --> ata port
suspend.
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
9a6d6a2dda