forked from Minki/linux
2f556bdb9f
Add an extcon driver for USB OTG ports controlled by an Intel INT3496 ACPI device (e.g. Baytrail, Cherrytrail devices). Signed-off-by: David Cohen <david.a.cohen@intel.com> [hdgoede@redhat.com: Port to current kernel, cleanup, submit upstream] [hdgoede@redhat.com: Add Documentation/extcon/intel-int3496.txt] Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
23 lines
1.1 KiB
Plaintext
23 lines
1.1 KiB
Plaintext
Intel INT3496 ACPI device extcon driver documentation
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The Intel INT3496 ACPI device extcon driver is a driver for ACPI
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devices with an acpi-id of INT3496, such as found for example on
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Intel Baytrail and Cherrytrail tablets.
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This ACPI device describes how the OS can read the id-pin of the devices'
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USB-otg port, as well as how it optionally can enable Vbus output on the
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otg port and how it can optionally control the muxing of the data pins
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between an USB host and an USB peripheral controller.
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The ACPI devices exposes this functionality by returning an array with up
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to 3 gpio descriptors from its ACPI _CRS (Current Resource Settings) call:
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Index 0: The input gpio for the id-pin, this is always present and valid
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Index 1: The output gpio for enabling Vbus output from the device to the otg
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port, write 1 to enable the Vbus output (this gpio descriptor may
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be absent or invalid)
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Index 2: The output gpio for muxing of the data pins between the USB host and
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the USB peripheral controller, write 1 to mux to the peripheral
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controller
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