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authorLaurent Pinchart <laurent.pinchart@ideasonboard.com>2018-05-26 23:51:57 +0200
committerLaurent Pinchart <laurent.pinchart@ideasonboard.com>2018-09-24 17:54:32 +0200
commit61ff10e0ea0cb39c737eab7e4fc5f0ae4d0fff33 (patch)
tree8e223ae0ac15fa3eaddddb4ca32a63b861ae7a64 /Documentation/ABI
parentusb: gadget: uvc: configfs: Add interface number attributes (diff)
downloadlinux-61ff10e0ea0cb39c737eab7e4fc5f0ae4d0fff33.tar.xz
linux-61ff10e0ea0cb39c737eab7e4fc5f0ae4d0fff33.zip
usb: gadget: uvc: configfs: Add bFormatIndex attributes
The UVC format description are numbered using the descriptor's bFormatIndex field. The index is used in UVC requests, and is thus needed to handle requests in userspace. Make it dynamically discoverable by exposing it in a bFormatIndex configfs attribute of the uncompressed and mjpeg format config items. The bFormatIndex value exposed through the attribute is stored in the config item private data. However, that value is never set: the driver instead computes the bFormatIndex value when linking the stream class header in the configfs hierarchy and stores it directly in the class descriptors in a separate structure. In order to expose the value through the configfs attribute, store it in the config item private data as well. This results in a small code simplification. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Diffstat (limited to 'Documentation/ABI')
-rw-r--r--Documentation/ABI/testing/configfs-usb-gadget-uvc8
1 files changed, 8 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/configfs-usb-gadget-uvc b/Documentation/ABI/testing/configfs-usb-gadget-uvc
index 490a0136fb02..a6cc8d6d398e 100644
--- a/Documentation/ABI/testing/configfs-usb-gadget-uvc
+++ b/Documentation/ABI/testing/configfs-usb-gadget-uvc
@@ -168,6 +168,10 @@ Description: Specific MJPEG format descriptors
All attributes read only,
except bmaControls and bDefaultFrameIndex:
+ bFormatIndex - unique id for this format descriptor;
+ only defined after parent header is
+ linked into the streaming class;
+ read-only
bmaControls - this format's data for bmaControls in
the streaming header
bmInterfaceFlags - specifies interlace information,
@@ -212,6 +216,10 @@ Date: Dec 2014
KernelVersion: 4.0
Description: Specific uncompressed format descriptors
+ bFormatIndex - unique id for this format descriptor;
+ only defined after parent header is
+ linked into the streaming class;
+ read-only
bmaControls - this format's data for bmaControls in
the streaming header
bmInterfaceFlags - specifies interlace information,