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authorMauro Carvalho Chehab <mchehab+samsung@kernel.org>2019-06-28 15:20:37 +0300
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2019-07-03 14:00:26 +0300
commit5d8cbf7176a427cd904eaa6efdaf6960d717b0de (patch)
tree8e2d09552554626373520e270972211306222e41 /Documentation/firmware-guide
parent9fe51603d953419b8da74f455269eca8e6b84228 (diff)
downloadlinux-5d8cbf7176a427cd904eaa6efdaf6960d717b0de.tar.xz
docs: extcon: convert it to ReST and move to ACPI dir
The intel-int3496.txt file is a documentation for an ACPI driver. There's no reason to keep it on a separate directory. So, instead of keeping it on some random location, move it to a sub-directory inside the ACPI documentation dir, renaming it to .rst. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Acked-by: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'Documentation/firmware-guide')
-rw-r--r--Documentation/firmware-guide/acpi/extcon-intel-int3496.rst33
-rw-r--r--Documentation/firmware-guide/acpi/index.rst1
2 files changed, 34 insertions, 0 deletions
diff --git a/Documentation/firmware-guide/acpi/extcon-intel-int3496.rst b/Documentation/firmware-guide/acpi/extcon-intel-int3496.rst
new file mode 100644
index 000000000000..5137ca834b54
--- /dev/null
+++ b/Documentation/firmware-guide/acpi/extcon-intel-int3496.rst
@@ -0,0 +1,33 @@
+=====================================================
+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
+ ======= =======
diff --git a/Documentation/firmware-guide/acpi/index.rst b/Documentation/firmware-guide/acpi/index.rst
index ae609eec4679..90c90d42d9ad 100644
--- a/Documentation/firmware-guide/acpi/index.rst
+++ b/Documentation/firmware-guide/acpi/index.rst
@@ -24,3 +24,4 @@ ACPI Support
acpi-lid
lpit
video_extension
+ extcon-intel-int3496