Utility to Suspend/Disable/Enable Power Off USB ports

[Hans Petter Selasky]

Hi Anish,

I think that when you re-enable the port the kernel should do a 
re-enumeration.

Also when you suspend/resume a device, the "suspend" and "resume" methods of 
the device should get called. I will have a look at it.

--HPS

On Thursday 06 March 2008, Anish Mistry wrote:
> On Thursday 06 March 2008, Hans Petter Selasky wrote:
> > Hi,
> >
> > I think that we should have this functionality in the USB kernel
> > like a separate IOCTL, that only takes an USB address like
> > argument, hence every USB device in the kernel knows which is its
> > parent HUB.
>
> Yes, this would be ideal.
>
> > There is a problem when you do a port reset, and that is that the
> > USB device goes into the unaddressed state, and starts responding
> > to address 0. If another device is being enumerated at the same
> > time, this might cause problems.
>
> Hmmm...Any suggestions?
>
> > BTW: What are the main purposes of your program?
>
> To shutoff a USB device so that it knows to stop.  See my email
> earlier to the list entitled "Suspend/Sleep/Stop USB device".
> Basically my built-in camera was getting hot and drawing power.  I
> needed a way to shut it down as not to waste power.
>
> > --HPS
> >
> > On Wednesday 05 March 2008, Anish Mistry wrote:
> > > I've written the upower utility allows you to selectively suspend
> > > usb ports.  It acts similar to the Windows "Stop Removable
> > > Device" process.  It has only been tested on 7.0-RELEASE.
> > >
> > > WARNING: This program may eat your lunch and kick your dog.
> > > You've been warned.
> > >
> > > Download and compile.
> > >
> > > fetch http://am-productions.biz/docs/upower.c
> > > gcc -o upower upower.c
> > >
> > > You will need to be root or have rw access to the uhub devices.
> > > eg. /dev/usbX
> > >
> > > Use "usbdevs -v" to find the port/device to suspend.
> > > # usbdevs -v
> > > Controller /dev/usb0:
> > > addr 1: full speed, self powered, config 1, UHCI root
> > > hub(0x0000), Intel(0x0000), rev 1.00
> > >  port 1 powered
> > >  port 2 powered
> > > Controller /dev/usb1:
> > > addr 1: full speed, self powered, config 1, UHCI root
> > > hub(0x0000), Intel(0x0000), rev 1.00
> > >  port 1 powered
> > >  port 2 addr 2: low speed, power 100 mA, config 1, product 0x0009
> > > (0x0009), vendor 0x045e(0x045e), rev 1.05
> > > Controller /dev/usb2:
> > > addr 1: full speed, self powered, config 1, UHCI root
> > > hub(0x0000), Intel(0x0000), rev 1.00
> > >  port 1 powered
> > >  port 2 addr 2: full speed, power 100 mA, config 1, Fingerprint
> > > Sensor(0x2580), vendor 0x08ff(0x08ff), rev 6.23
> > > Controller /dev/usb3:
> > > addr 1: full speed, self powered, config 1, UHCI root
> > > hub(0x0000), Intel(0x0000), rev 1.00
> > >  port 1 powered
> > >  port 2 powered
> > > Controller /dev/usb4:
> > > addr 1: high speed, self powered, config 1, EHCI root
> > > hub(0x0000), Intel(0x0000), rev 1.00
> > >  port 1 powered
> > >  port 2 powered
> > >  port 3 addr 2: high speed, self powered, config 1, product
> > > 0x005a(0x005a), vendor 0x0409(0x0409), rev 1.00
> > >   port 1 powered
> > >   port 2 powered
> > >   port 3 powered
> > >   port 4 powered
> > >  port 4 powered
> > > Controller /dev/usb5:
> > > addr 1: high speed, self powered, config 1, EHCI root
> > > hub(0x0000), Intel(0x0000), rev 1.00
> > >  port 1 powered
> > >  port 2 powered
> > >  port 3 powered
> > >  port 4 addr 2: high speed, power 320 mA, config 1, Sirius USB2.0
> > > Camera(0x3343), Vimicro Corp.(0x0ac8), rev 1.00
> > >
> > >
> > > Since my built-in USB camera draws power when not in use, I'll
> > > suspend it to save battery time.
> > >
> > > # ./upower /dev/usb5 4 suspend