Software Interface; Sysfs; Procfs - Texas Instruments OMAP35 Series User Manual

10.4. Software Interface

The USB driver exposes its state/control through the sysfs and the procfs
interfaces. The following sections talks about these.

10.4.1. sysfs

Table 10.1. OMAP3 USB Driver: sysfs attributes

10.4.2. procfs

The profcs entry /proc/driver/musb_hdrc is used to control the driver
behaviour as well as check the status of the driver.
The following command will show the usage of this proc entry
Specifically the most important usage of this entry would be to start an USB
session(host mode) by issuing the following command:
Version 02.01.01.08
SYSFS attribute Description
mode The
musb_hdrc.0/mode is a read-only entry. It will
show the state of the OTG (though this feature
is not supported) state machine. This will be true
even if the driver has been compiled without
OTG support. Only the states like A_HOST,
B_PERIPHERAL, that makes sense for non-OTG
will show up.
vbus The
musb_hdrc.0/vbus is a write-only entry. It is used
to set the VBUS timeout value during OTG. If the
current OTG state is a_wait_bcon then then urb
submission is disabled.
$ echo "?" > /proc/driver/musb_hdrc
$ echo "F" > /proc/driver/musb_hdrc
Platform Support Products
entry
/sys/devices/platform/
entry
/sys/devices/platform/
USB Driver
Software Interface
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