Usb Otg (Hnp/Srp) Testing - Texas Instruments OMAP35 Series User Manual

For details on usage of USBNet, refer this url. [http://embedded.seattle.intel
research.net/wiki/index.php?title=Setting_up_USBnet]

10.3.13. USB OTG (HNP/SRP) testing

Please choose the configuration as described in driver configuration section for
OTG and follow the steps below for testing.
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Version 02.01.01.08
Boot the OTG build image on two OMAP35xx EVM.
If gadget driver is built as module then insert it to complete USB
initialization.
Connect mini-A side of the OTG cable to one of the EVM (say EVM-1) and
mini-B side on the other (say EVM-2).
In this scenario EVM-1 will become initial host or A-device and EVM-2
will become initial device or B-device.A-device will provide bus power
throughout the bus communication even if it becomes peripheral using HNP.
There will not be any connect event at this point of time as Vbus power is
not yet switched-on.Vbus power can be switched-on from A-device or from
B-device using SRP.
Request to switch-on the Vbus power using below command on any EVM.
$ echo "F" > /proc/driver/musb_hdrc
If this command is executed on B-device then SRP protocol will be used to
request A-device to switch-on the Vbus power.
Now the connect event occurs, enumeration will complete and gadget driver
on B-device will be ready to use if this driver is in "Targeted Peripheral List
(TPL)" of A-device.
If TPL is disabled on A-device then gadget driver will be ready to use soon
after enumeration.
If TPL is enabled and gadget driver of B-device is not in TPL list of A-device
then there will be an automatic trial of HNP from usb core by suspending
the bus.This will cause a role switch and B-device will enumerate A-device.
Now the gadget driver of A-device will be configured if it is on the TPL list
of B-device.
Currently this is the only way possible for HNP testing but we have added
a suspend proc entry to start HNP in other than this scenario.
Complete all the communication between A-device and B-device.
Start HNP by executing below command on host side.
Platform Support Products
USB Driver
USB OTG (HNP/SRP) testing
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