How to power on/ power off USB_VBUS ? (am3359. kernel 3.12.10)

Shamrel Alexander

Hello!
How to power on/ power off USB_VBUS ? Board is based on Beaglebone Black. Kernel -- 3.12.10-ti2013.12.01.
The previous time I did it in that way:
echo "suspend"> /sys/bus/usb/devices/usb1/power/level
This method doesn't work any more.
The documentation recommends to use: power/level and power/autosuspend
How does it work?
Is there some special settings to be implemented in the kernel?

over 10 years ago

0 Biser Gatchev-XID over 10 years ago

TI__Guru**** 393215 points

Hi,

Check this thread: http://e2e.ti.com/support/arm/sitara_arm/f/791/t/224721.aspx

0 Shamrel Alexander over 10 years ago in reply to Biser Gatchev-XID

Prodigy 170 points

It doesn't work.

By USB1 connected FT2232h:

# lsusb
Bus 001 Device 002: ID 0403:6010 Future Technology Devices International, Ltd FT2232C Dual USB-UART/FIFO IC
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

# cat /sys/bus/usb/devices/1-1/power/autosuspend
2

# cat /sys/bus/usb/devices/1-1/power/control
auto

# ls /sys/bus/usb/devices/
1-0:1.0 1-1 1-1:1.0 1-1:1.1 2-0:1.0 usb1 usb2

Disconnect the device:

# echo 1-1 >/sys/bus/usb/drivers/usb/unbind
[ 111.383167] ftdi_sio ttyUSB0: FTDI USB Serial Device converter now disconnected from ttyUSB0
[ 111.401570] ftdi_sio 1-1:1.0: device disconnected
[ 111.414922] ftdi_sio ttyUSB1: FTDI USB Serial Device converter now disconnected from ttyUSB1
[ 111.429080] ftdi_sio 1-1:1.1: device disconnected

But the line voltage VBUS saved! Where am I wrong?

0 Shamrel Alexander over 10 years ago in reply to Shamrel Alexander

Prodigy 170 points

Hi!

One way to turn off/on the power:

#devmem2 0x47401460 b 0x00
#devmem2 0x47401460 b 0x01

But this is not the right way!

Processors

Processors forum

How to power on/ power off USB_VBUS ? (am3359. kernel 3.12.10)