Disable USB power via PSW

[idata]

Looking at the schematic for the sparkfun base block (and I believe the mini-breakout board), the PSW pin on the edison connects to a MIC2039 to control power to the OTG USB connection. I'm working on a product that needs to disable the USB power. (the device it connects to is not smart enough to suspend correctly)

The above link mentions using echo '1-1' > unbind in /sys/bus/usb/drivers/usb but this does not appear to have any effect. My voltage meter in the usb path still shows 5v. Is there a way I can control the PSW pin to disable USB when needed?

Thanks,

Ryan

[idata]

Hi Ryan,

Please let us investigate this case a little bit more, we'll get back to you as soon as we have a more accurate answer.Regards,Pablo

[idata]

Thanks Pablo, any help here would be greatly appreciated.

- Ryan

[idata]

Pablo,

Any updates?

Thanks,

Ryan

[idata]

Hi Ryan,

Thank you for your patience. For the mini-breakout board, as you can see in the schematic in page 6 of the following document http://www.intel.com/content/dam/support/us/en/documents/edison/sb/mini_edison_breakout_hvm_8_26.pdf http://www.intel.com/content/dam/support/us/en/documents/edison/sb/mini_edison_breakout_hvm_8_26.pdf, VCC of the OTG USB is connected to VBUS, the connection needs to be disconnected at the hardware level on the board.Regards,Pablo

[idata]

Pablo, so PSW can't be controlled from linux?

[idata]

Hi Ryan,

It is no longer possible using the bind/unbind command, we also tested it and got the same results as you. We will investigate if there's any other way to control the pin from Linux. But for now, I would suggest you to go on with the hardware method as it is the one that will certainly work.Regards, Pablo

[idata]

Pablo,

Thanks for letting me know. Yea, looks like they removed support for that in the linux kernel (not sure why). We're ANDing PSW+a gpio pin on our board that goes to the enable on our usb power, so that should work.

Thanks,

Ryan