From 2c0f62f9e4f2c450342369dfd5858db51bc90fe3 Mon Sep 17 00:00:00 2001 From: Andrzej Pietrasiewicz Date: Tue, 16 Dec 2014 14:56:29 +0100 Subject: [PATCH] Documentation: usb: FFS function testing Summary of how to test FFS (FunctionFS) function of USB gadget. Signed-off-by: Andrzej Pietrasiewicz Signed-off-by: Felipe Balbi --- Documentation/usb/gadget-testing.txt | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) diff --git a/Documentation/usb/gadget-testing.txt b/Documentation/usb/gadget-testing.txt index 50b0a6cc6674..141a1d01f312 100644 --- a/Documentation/usb/gadget-testing.txt +++ b/Documentation/usb/gadget-testing.txt @@ -5,6 +5,7 @@ provided by gadgets. 2. ECM function 3. ECM subset function 4. EEM function +5. FFS function 1. ACM function @@ -134,3 +135,26 @@ Configure IP addresses of the device and the host. Then: On the device: ping On the host: ping + +5. FFS function +=============== + +The function is provided by usb_f_fs.ko module. + +Function-specific configfs interface +------------------------------------ + +The function name to use when creating the function directory is "ffs". +The function directory is intentionally empty and not modifiable. + +After creating the directory there is a new instance (a "device") of FunctionFS +available in the system. Once a "device" is available, the user should follow +the standard procedure for using FunctionFS (mount it, run the userspace +process which implements the function proper). The gadget should be enabled +by writing a suitable string to usb_gadget//UDC. + +Testing the FFS function +------------------------ + +On the device: start the function's userspace daemon, enable the gadget +On the host: use the USB function provided by the device -- 2.20.1