ahci_platform_get_resources handles resource management for
platform AHCI drivers, including getting a possible PHY
from the device tree. Since not all drivers need a PHY, it
ignores -ENODEV and -ENOSYS from devm_get_phy. However, when
the PHY subsystem is mistakenly disabled, -ENOSYS can be
returned even when a PHY is needed.

This patch modifies the -ENOSYS case to check if a "phys"
device tree node exists. If it exists, then clearly the PHY
subsystem is mistakenly disabled and the driver cannot work,
ahci_platform_get_resources will fail and propagate the error.

Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
Acked-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

Add a dynamic host_flags argument to make ahci_platform_init_host more flexible,
then remove the AHCI_HFLAGS(...) argument from some driver's ata_port_info,
and pass that in as the new argument.

Cc: Hans de Geode <hdegoede@redhat.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Kefeng Wang <kefeng.wang@linaro.org>
Signed-off-by: Tejun Heo <tj@kernel.org>

Move AHCI platform library code from ahci_platform.c to
libahci_platform.c and fix dependencies for ahci_st,
ahci_imx and ahci_sunxi drivers.

Acked-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Tejun Heo <tj@kernel.org>