Hi, I am referring to the i.MX Linux® Reference Manual, specifically Section 39.2.4. I am attempting to replicate the instructions provided on how to set the USB OTG as a wakeup when the system enters Suspend-to-RAM.
echo enabled > /sys/bus/platform/devices/20c9000.usbphy/power/wakeup
echo enabled > /sys/bus/platform/devices/2184000.usb/power/wakeup
echo enabled > /sys/bus/platform/devices/ci_hdrc.0/power/wakeup
I do not see the these devices in the /sys/bus/platform/devices folder. Is there something that needs to be done on my end to make these devices available?
I'm specifically working off of a Google Coral Dev Board running the i.MX 8M SoC. I'm running Linux Mendel Eagle.
Solved! Go to Solution.
it is necessary to run the following command before suspend to enable USB wakeup:
echo enabled > /sys/devices/platform/usb@38200000/38200000.dwc3/xhci-hcd.0.auto/power/wakeup
Best regards
igor
Hi,
The patches have already been applied by the Google dev team about a year ago. So the Mendel Kernel image that I was using must have had this workaround already implemented.
With that in mind, how would I go about enabling wakeup on a USB device? What commands do I need write to the CLI?
Thanks
it is necessary to run the following command before suspend to enable USB wakeup:
echo enabled > /sys/devices/platform/usb@38200000/38200000.dwc3/xhci-hcd.0.auto/power/wakeup
Best regards
igor
Thank you Igor! This did the trick.
Hi murreletinnovation
unfortunately this may not work due to USB e11231 erratum
Mask Set Errata for Mask 2N14W
Best regards
igor
Hi Igor,
Thank you for the quick response. In the erratum, I see a potential workaround for this issue.
"Requires RUN/STOP bit to be set to 1 during suspend mode."
Where exactly can I set the RUN/STOP bit?
Thanks!
Hi murreletinnovation
additional patches were sent via mail.
Best regards
igor
Hi Igor,
I want to let an LTE USB device wake up the system. I have searched the kernel source tree (lf-5.10.y) but failed (maybe missed) to find the patch that implements the SW workaround for ERR11231.
Could you please send that patch to me as well? Thanks in advance.
BR
Ray
Hi Igor,
Thank you for the patches. I am trying to build the Mendel source tree with the patches. My environment wasn't originally set up to do so, so I am fixing that situation first. I will update when I am able to flash the device and verify if the USB Wakeup is functional.
Thank you