USB: gadget: Add support to enable streaming mode with required function
Supported different usb functions' has different throughput requirement.
USB controller supports streaming mode feature which enables double
buffering scheme on both IN and OUT endpoint, and reduces number of
NAKs for IN transfer. Hence noticeble throughput is increased with it.
Currently streaming mode is disable with USB controller. As supported
usb functions'like mtp, rndis are required to have higher throughput.
Add support which allows to enable streaming mode with usb controller
in device mode when particular function based composition is being enabled.
CRs-Fixed: 550553
Change-Id: Ibf6f3dc3f3b821647ba9beb15ed735a85c8ed586
Signed-off-by: Mayank Rana <mrana@codeaurora.org>
diff --git a/Documentation/devicetree/bindings/usb/msm-hsusb.txt b/Documentation/devicetree/bindings/usb/msm-hsusb.txt
index da36f3a..714311e 100644
--- a/Documentation/devicetree/bindings/usb/msm-hsusb.txt
+++ b/Documentation/devicetree/bindings/usb/msm-hsusb.txt
@@ -181,12 +181,19 @@
- qcom,android-usb-cdrom : if this property is present then device creates
a new LUN as CD-ROM
- qcom,android-usb-internal-ums : if this property is present then device
- creates a new LUN as internal usb mass storage
+ creates a new LUN as internal usb mass storage.
+- qcom,streaming-func : add list of usb function name. If mention usb function
+ is being enable as part of USB composition, streaming mode is enable with
+ usb device controller to get better throughput. NOTE: Inverted CRC and
+ turnaround timeout is observed on enabling streaming. Hence it is required
+ to see these errors and number of erros on enabling this at USB level to make
+ final decision to enable this feature or not.
Example Android USB device node :
android_usb@fc42b0c8 {
compatible = "qcom,android-usb";
reg = <0xfc42b0c8 0xc8>;
qcom,android-usb-swfi-latency = <1>;
+ qcom,streaming-func = "rndis","mtp";
};