This patch is to add usb port auto power off mechanism.
When usb device is suspending, usb core will suspend usb port and
usb port runtime pm callback will clear PORT_POWER feature to
power off port if all conditions were met. These conditions are
remote wakeup disable, pm qos NO_POWER_OFF flag clear and persist
enable. When it resumes, power on port again.

Add did_runtime_put in the struct usb_port to ensure
pm_runtime_get/put(portdev) to be called pairedly.  Set did_runtime_put
to true when call pm_runtime_put(portdev) during suspending. The
pm_runtime_get(portdev) only will be called when did_runtime_put
is set to true during resuming. Set did_runtime_put to false after
calling pm_runtime_get(portdev).

Make clear_port_feature() and hdev_to_hub() as global symbol.
Rename clear_port_feature() to usb_clear_port_feature() and
hdev_to_hub() to usb_hub_to_struct_hub().

Extend hub_port_debounce() with the fuction of debouncing to
be connected. Add two wraps: hub_port_debounce_be_connected()
and hub_port_debouce_be_stable().

Increase HUB_DEBOUNCE_TIMEOUT to 2000 because some usb ssds
needs around 1.5 or more to make the hub port status to be
connected steadily after being powered off and powered on.
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Acked-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: NLan Tianyu <tianyu.lan@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch is to add runtime pm callback for usb port device.
Set/clear PORT_POWER feature in the resume/suspend callback.
Add portnum for struct usb_port to record port number. Do
pm_rumtime_get_sync/put(portdev) when a device is plugged/unplugged
to prevent it from being powered off when it is active.
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Acked-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: NLan Tianyu <tianyu.lan@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch is to register usb port's acpi power resources. Create
link between usb port device and its acpi power resource.
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NLan Tianyu <tianyu.lan@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Some platforms provide usb port connect types through ACPI. This
patch is to add this new attribute to expose these information
to user space.
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NLan Tianyu <tianyu.lan@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch is to fix compilation error and warning on the arm and blackfin.
Add linux/slab.h head file to driver/usb/core/port.c. These are reported
from 0-DAY kernel build testing backend.

head:   6e30d7cb
commit: 6e30d7cb [26/26] usb: Add driver/usb/core/(port.c,hub.h) files
config: make ARCH=arm at91_dt_defconfig

All error/warnings:

   drivers/usb/core/port.c: In function 'usb_port_device_release':
>> drivers/usb/core/port.c:25:2: error: implicit declaration of function 'kfree' [-Werror=implicit-function-declaration]
   drivers/usb/core/port.c: In function 'usb_hub_create_port_device':
>> drivers/usb/core/port.c:38:2: error: implicit declaration of function 'kzalloc' [-Werror=implicit-function-declaration]
>> drivers/usb/core/port.c:38:40: error: 'GFP_KERNEL' undeclared (first use in this function)
   drivers/usb/core/port.c:38:40: note: each undeclared identifier is reported only once for each function it appears in
   cc1: some warnings being treated as errors

head:   6e30d7cb
commit: 6e30d7cb [26/26] usb: Add driver/usb/core/(port.c,hub.h) files
config: make ARCH=blackfin BF526-EZBRD_defconfig

All warnings:

   drivers/usb/core/port.c: In function 'usb_port_device_release':
   drivers/usb/core/port.c:25:2: error: implicit declaration of function 'kfree' [-Werror=implicit-function-declaration]
   drivers/usb/core/port.c: In function 'usb_hub_create_port_device':
   drivers/usb/core/port.c:38:2: error: implicit declaration of function 'kzalloc' [-Werror=implicit-function-declaration]
>> drivers/usb/core/port.c:38:11: warning: assignment makes pointer from integer without a cast [enabled by default]
   cc1: some warnings being treated as errors
Reported-by: NFengguang Wu <wfg@linux.intel.com>
Signed-off-by: NLan Tianyu <tianyu.lan@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch is to create driver/usb/core/(port.c,hub.h) files and move usb
port related code into port.c.
Signed-off-by: NLan Tianyu <tianyu.lan@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>