1===================================================== 2Intel INT3496 ACPI device extcon driver documentation 3===================================================== 4 5The Intel INT3496 ACPI device extcon driver is a driver for ACPI 6devices with an acpi-id of INT3496, such as found for example on 7Intel Baytrail and Cherrytrail tablets. 8 9This ACPI device describes how the OS can read the id-pin of the devices' 10USB-otg port, as well as how it optionally can enable Vbus output on the 11otg port and how it can optionally control the muxing of the data pins 12between an USB host and an USB peripheral controller. 13 14The ACPI devices exposes this functionality by returning an array with up 15to 3 gpio descriptors from its ACPI _CRS (Current Resource Settings) call: 16 17======= ===================================================================== 18Index 0 The input gpio for the id-pin, this is always present and valid 19Index 1 The output gpio for enabling Vbus output from the device to the otg 20 port, write 1 to enable the Vbus output (this gpio descriptor may 21 be absent or invalid) 22Index 2 The output gpio for muxing of the data pins between the USB host and 23 the USB peripheral controller, write 1 to mux to the peripheral 24 controller 25======= ===================================================================== 26 27There is a mapping between indices and GPIO connection IDs as follows 28 29 ======= ======= 30 id index 0 31 vbus index 1 32 mux index 2 33 ======= ======= 34