usb/acpi: Store info on device removability.

In the upcoming USB port power off patches, we need to know whether a
USB port can ever see a disconnect event.  Often USB ports are internal
to a system, and users can't disconnect USB devices from that port.
Sometimes those ports will remain empty, because the OEM chose not to
connect an internal USB device to that port.

According to ACPI Spec 9.13, PLD indicates whether USB port is
user visible and _UPC indicates whether a USB device can be connected to
the USB port (we'll call this "connectible").  Here's a matrix of the
possible combinations:

Visible Connectible
		Name		Example
-------------------------------------------------------------------------

Yes	No	Unknown		(Invalid state.)

Yes	Yes	Hot-plug	USB ports on the outside of a laptop.
				A user could freely connect and disconnect
				USB devices.

No	Yes	Hard-wired	A USB modem hard-wired to a port on the
				inside of a laptop.

No	No	Not used	The port is internal to the system and
				will remain empty.

Represent each of these four states with an enum usb_port_connect_type.
The four states are USB_PORT_CONNECT_TYPE_UNKNOWN,
USB_PORT_CONNECT_TYPE_HOT_PLUG, USB_PORT_CONNECT_TYPE_HARD_WIRED, and
USB_PORT_NOT_USED.  When we get the USB port's acpi_handle, store the
state in connect_type in struct usb_port.

Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 4 insertions, 0 deletions

diff --git a/drivers/usb/core/usb.h b/drivers/usb/core/usb.h
index 1633f6e99e35..1c528c1bf0be 100644
--- a/drivers/usb/core/usb.h
+++ b/drivers/usb/core/usb.h
@@ -169,6 +169,10 @@ extern void usb_notify_add_device(struct usb_device *udev);
 extern void usb_notify_remove_device(struct usb_device *udev);
 extern void usb_notify_add_bus(struct usb_bus *ubus);
 extern void usb_notify_remove_bus(struct usb_bus *ubus);
+extern enum usb_port_connect_type
+	usb_get_hub_port_connect_type(struct usb_device *hdev, int port1);
+extern void usb_set_hub_port_connect_type(struct usb_device *hdev, int port1,
+	enum usb_port_connect_type type);
 
 #ifdef CONFIG_ACPI
 extern int usb_acpi_register(void);