On Mon, Sep 11, 2023 at 01:02:01PM +0900, Damien Le Moal wrote:
> There is no direct device ancestry defined between an ata_device and
> its scsi device which prevents the power management code from correctly
> ordering suspend and resume operations. Create such ancestry with the
> ata device as the parent to ensure that the scsi device (child) is
> suspended before the ata device and that resume handles the ata device
> before the scsi device.
>
> The parent-child (supplier-consumer) relationship is established between
> the ata_port (parent) and the scsi device (child) with the function
> device_add_link(). The parent used is not the ata_device as the PM
> operations are defined per port and the status of all devices connected
> through that port is controlled from the port operations.
>
> The device link is established with the new function
> ata_scsi_dev_alloc(). This function is used to define the ->slave_alloc
> callback of the scsi host template of most drivers.
>
> Fixes: a19a93e4c6a9 ("scsi: core: pm: Rely on the device driver core for async power management")
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Damien Le Moal <dlemoal@xxxxxxxxxx>
Tested-by: Chia-Lin Kao (AceLan) <acelan.kao@xxxxxxxxxxxxx>
