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linux/Documentation/devicetree/bindings/extcon/extcon-usb-gpio.txt

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extcon: usb-gpio: Introduce gpio usb extcon driver This driver observes the USB ID pin connected over a GPIO and updates the USB cable extcon states accordingly. The existing GPIO extcon driver is not suitable for this purpose as it needs to be taught to understand USB cable states and it can't handle more than one cable per instance. For the USB case we need to handle 2 cable states. 1) USB (attach/detach) 2) USB-HOST (attach/detach) This driver can be easily updated in the future to handle VBUS events in case it happens to be available on GPIO for any platform. Signed-off-by: Roger Quadros <rogerq@ti.com> Reviewed-by: Felipe Balbi <balbi@ti.com> Acked-by: Felipe Balbi <balbi@ti.com> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2015-02-02 18:21:59 +08:00
USB GPIO Extcon device
This is a virtual device used to generate USB cable states from the USB ID pin
connected to a GPIO pin.
Required properties:
- compatible: Should be "linux,extcon-usb-gpio"
extcon: usb-gpio: Add VBUS detection support Driver can now work with both ID and VBUS pins or either one of them. There can be the following 3 cases 1) Both ID and VBUS GPIOs are available: ID = LOW -> USB_HOST active, USB inactive ID = HIGH -> USB_HOST inactive, USB state is same as VBUS. 2) Only ID GPIO is available: ID = LOW -> USB_HOST active, USB inactive ID = HIGH -> USB_HOST inactive, USB active 3) Only VBUS GPIO is available: VBUS = LOW -> USB_HOST inactive, USB inactive VBUS = HIGH -> USB_HOST inactive, USB active Signed-off-by: Roger Quadros <rogerq@ti.com> Reviewed-by: Peter Chen <peter.chen@nxp.com> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2016-09-20 22:53:55 +08:00
Either one of id-gpio or vbus-gpio must be present. Both can be present as well.
extcon: usb-gpio: Introduce gpio usb extcon driver This driver observes the USB ID pin connected over a GPIO and updates the USB cable extcon states accordingly. The existing GPIO extcon driver is not suitable for this purpose as it needs to be taught to understand USB cable states and it can't handle more than one cable per instance. For the USB case we need to handle 2 cable states. 1) USB (attach/detach) 2) USB-HOST (attach/detach) This driver can be easily updated in the future to handle VBUS events in case it happens to be available on GPIO for any platform. Signed-off-by: Roger Quadros <rogerq@ti.com> Reviewed-by: Felipe Balbi <balbi@ti.com> Acked-by: Felipe Balbi <balbi@ti.com> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2015-02-02 18:21:59 +08:00
- id-gpio: gpio for USB ID pin. See gpio binding.
extcon: usb-gpio: Add VBUS detection support Driver can now work with both ID and VBUS pins or either one of them. There can be the following 3 cases 1) Both ID and VBUS GPIOs are available: ID = LOW -> USB_HOST active, USB inactive ID = HIGH -> USB_HOST inactive, USB state is same as VBUS. 2) Only ID GPIO is available: ID = LOW -> USB_HOST active, USB inactive ID = HIGH -> USB_HOST inactive, USB active 3) Only VBUS GPIO is available: VBUS = LOW -> USB_HOST inactive, USB inactive VBUS = HIGH -> USB_HOST inactive, USB active Signed-off-by: Roger Quadros <rogerq@ti.com> Reviewed-by: Peter Chen <peter.chen@nxp.com> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2016-09-20 22:53:55 +08:00
- vbus-gpio: gpio for USB VBUS pin.
extcon: usb-gpio: Introduce gpio usb extcon driver This driver observes the USB ID pin connected over a GPIO and updates the USB cable extcon states accordingly. The existing GPIO extcon driver is not suitable for this purpose as it needs to be taught to understand USB cable states and it can't handle more than one cable per instance. For the USB case we need to handle 2 cable states. 1) USB (attach/detach) 2) USB-HOST (attach/detach) This driver can be easily updated in the future to handle VBUS events in case it happens to be available on GPIO for any platform. Signed-off-by: Roger Quadros <rogerq@ti.com> Reviewed-by: Felipe Balbi <balbi@ti.com> Acked-by: Felipe Balbi <balbi@ti.com> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2015-02-02 18:21:59 +08:00
Example: Examples of extcon-usb-gpio node in dra7-evm.dts as listed below:
extcon_usb1 {
compatible = "linux,extcon-usb-gpio";
id-gpio = <&gpio6 1 GPIO_ACTIVE_HIGH>;
}
&omap_dwc3_1 {
extcon = <&extcon_usb1>;
};