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+=====================================================
+Intel INT3496 ACPI device extcon driver documentation
+=====================================================
+
+The Intel INT3496 ACPI device extcon driver is a driver for ACPI
+devices with an acpi-id of INT3496, such as found for example on
+Intel Baytrail and Cherrytrail tablets.
+
+This ACPI device describes how the OS can read the id-pin of the devices'
+USB-otg port, as well as how it optionally can enable Vbus output on the
+otg port and how it can optionally control the muxing of the data pins
+between an USB host and an USB peripheral controller.
+
+The ACPI devices exposes this functionality by returning an array with up
+to 3 gpio descriptors from its ACPI _CRS (Current Resource Settings) call:
+
+======= =====================================================================
+Index 0 The input gpio for the id-pin, this is always present and valid
+Index 1 The output gpio for enabling Vbus output from the device to the otg
+ port, write 1 to enable the Vbus output (this gpio descriptor may
+ be absent or invalid)
+Index 2 The output gpio for muxing of the data pins between the USB host and
+ the USB peripheral controller, write 1 to mux to the peripheral
+ controller
+======= =====================================================================
+
+There is a mapping between indices and GPIO connection IDs as follows
+
+ ======= =======
+ id index 0
+ vbus index 1
+ mux index 2
+ ======= =======