USB: otg: gpio_vbus transceiver stub

gpio_vbus provides simple GPIO VBUS sensing for peripheral
controllers with an internal transceiver.
Optionally, a second GPIO can be used to control D+ pullup.

It also interfaces with the regulator framework to limit charging
currents when powered via USB. gpio_vbus requests the regulator
supplying "vbus_draw" and can enable/disable it or limit its
current depending on USB state.

[dbrownell@users.sourceforge.net: use drivers/otg, cleanups ]

Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/otg/Kconfig b/drivers/usb/otg/Kconfig
index 8603429..afe91bf 100644
--- a/drivers/usb/otg/Kconfig
+++ b/drivers/usb/otg/Kconfig
@@ -14,6 +14,19 @@
 	  Select this to make sure the build includes objects from
 	  the OTG infrastructure directory.
 
+#
+# USB Transceiver Drivers
+#
+config USB_GPIO_VBUS
+	tristate "GPIO based peripheral-only VBUS sensing 'transceiver'"
+	depends on GENERIC_GPIO
+	select USB_OTG_UTILS
+	help
+	  Provides simple GPIO VBUS sensing for controllers with an
+	  internal transceiver via the otg_transceiver interface, and
+	  optionally control of a D+ pullup GPIO as well as a VBUS
+	  current limit regulator.
+
 config ISP1301_OMAP
 	tristate "Philips ISP1301 with OMAP OTG"
 	depends on I2C && ARCH_OMAP_OTG