Hi Alan,
sorry for being a bit slow to respond this time.
On Thu, Jul 15, 2021 at 3:44 AM Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote:
[...]
> Martin, here's another test you can try, on both the Odroid and PC
> systems. Boot with usb.autosuspend=-1 on the command line to disable
Please note that in my tests below I used usbcore.autosuspend=-1 (so
s/usb./usbcore./)
I am assuming that usb.autosuspend is a typo because it doesn't seem
to make a difference for me.
usbcore.autosuspend=-1 is the one you recommended earlier which did
work around the issue on Odroid-C1.
> default runtime suspend. But then before plugging in the drive, start a
> usbmon trace and do:
>
> echo 2 >/sys/bus/usb/devices/1-2/power/autosuspend
>
> to enable runtime suspend for the Genesys Logic hub. (On the PC,
> replace the 1-2 with 1-5 or whatever the appropriate device path is for
> the GL hub.)
The steps on my PC are:
- boot with usbcore.autosuspend=-1 in the kernel cmdline (confirmed
using cat /proc/cmdline)
- start: cat /sys/kernel/debug/usb/usbmon/1u > 1u.mon-pc.out
- echo 2 > /sys/bus/usb/devices/1-7/power/autosuspend (which I chose
based on the lsusb output below)
- wait at least 5 seconds
- plug in my Corsair Voyager USB 3.0 flash drive
- wait one or two seconds until the device shows up in dmesg
- stop the cat command
- lsusb -vvt
/: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/10p, 480M
ID 1d6b:0002 Linux Foundation 2.0 root hub
/sys/bus/usb/devices/usb1 /dev/bus/usb/001/001
[...]
|__ Port 7: Dev 5, If 0, Class=Hub, Driver=hub/4p, 480M
ID 05e3:0610 Genesys Logic, Inc. Hub
/sys/bus/usb/devices/1-7 /dev/bus/usb/001/005
|__ Port 3: Dev 10, If 0, Class=Mass Storage, Driver=usb-storage, 480M
ID 1b1c:1a03 Corsair Voyager 3.0
/sys/bus/usb/devices/1-7.3 /dev/bus/usb/001/010
Please note that virtually all USB2 devices are connected through hubs
on bus 01 port 01 on this motherboard.
So the 1u.mon-pc.out output probably contains information for other
devices than the ones which are relevant here as well.
Then on my Odroid-C1:
- boot with usbcore.autosuspend=-1 in the kernel cmdline (confirmed
using cat /proc/cmdline)
- start: cat /sys/kernel/debug/usb/usbmon/0u > 0u.mon-odroidc1.out
- echo 2 > /sys/bus/usb/devices/1-1/power/autosuspend (which I chose
based on the lsusb output below)
- wait at least 5 seconds
- plug in my Corsair Voyager USB 3.0 flash drive
- wait a few seconds, the device is *not* being detected (no sign on
life in dmesg)
- stop the cat command
- lsusb -vvt
/: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=dwc2/1p, 480M
ID 1d6b:0002 Linux Foundation 2.0 root hub
/sys/bus/usb/devices/usb1 /dev/bus/usb/001/001
|__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/4p, 480M
ID 05e3:0610 Genesys Logic, Inc. Hub
/sys/bus/usb/devices/1-1 /dev/bus/usb/001/002
>From what I can tell the outputs related to device 005 (on my PC) as
well as 002 (on my Odroid-C1) are identical up to the point where
Odroid-C1 is then just silent.
The first message to the USB bus is different between the two (001) in
both cases. If I had to guess then the difference comes to the device
number of the hub within the payload.
> Wait at least two seconds for the hub to go into runtime suspend before
> plugging in the Corsair drive and stopping the trace. It might turn out
> that allowing the GL hub to suspend while keeping the DWC2 root hub
> active will make a difference.
>
> (The reason for doing this on the PC as well as on the Odroid is to make
> sure that the sequence of USB requests sent to the hub and responses
> received from it is exactly the same in both cases.)
If you want me to run any additional commands (either on my PC or
Odroid-C1) then please let me know.
In case it's of any help I attached the sysfs attributes for both
hubs. The only differences are:
- bcdDevice: 6060 (on my PC) vs 3298 (on Odroid-C1)
- urbnum: 72 (on my PC) vs 26 (on Odroid-C1)
As always: many thanks in advance, everyone's help on this is highly
appreciated!
Best regards,
Martin
authorized:1 avoid_reset_quirk:0 bcdDevice:6060 bConfigurationValue:1 bDeviceClass:09 bDeviceProtocol:02 bDeviceSubClass:00 bmAttributes:e0 bMaxPacketSize0:64 bMaxPower:100mA bNumConfigurations:1 bNumInterfaces: 1 busnum:1 idProduct:0610 idVendor:05e3 ltm_capable:no maxchild:4 product:USB2.0 Hub quirks:0x0 removable:unknown rx_lanes:1 speed:480 tx_lanes:1 urbnum:72 version: 2.00
Attachment:
1u.mon-pc.out
Description: Binary data
Attachment:
0u.mon-odroidc1.out
Description: Binary data
authorized:1 avoid_reset_quirk:0 bcdDevice:3298 bConfigurationValue:1 bDeviceClass:09 bDeviceProtocol:02 bDeviceSubClass:00 bmAttributes:e0 bMaxPacketSize0:64 bMaxPower:100mA bNumConfigurations:1 bNumInterfaces: 1 busnum:1 idProduct:0610 idVendor:05e3 ltm_capable:no maxchild:4 product:USB2.0 Hub quirks:0x0 removable:unknown rx_lanes:1 speed:480 tx_lanes:1 urbnum:26 version: 2.00
