Check if hub is used - Githubissues

peteruithoven commented 11 years ago

People can easily forget to use the hub, or they might not understand why it's important. It would be nice to warn people when they are connecting the printer without the hub.

I would not disable the use of the printer unless we are 100% sure all printer and hub types are properly handled by this check.

peteruithoven commented 11 years ago

The application lsusb should be able to give more info about device on command, but this always gives me a segmentation fault.

Interesting information is added to logread log:

connecting arduino directly

Thu Jan 1 00:22:21 1970 kern.info kernel: [ 1341.320000] usb 1-1: new full-speed USB device number 5 using ehci-platform
Thu Jan 1 00:22:21 1970 kern.info kernel: [ 1341.490000] cdc_acm 1-1:1.0: ttyACM0: USB ACM device

disconnecting arduino directly

Thu Jan 1 00:23:00 1970 kern.info kernel: [ 1380.470000] usb 1-1: USB disconnect, device number 5

connecting hub

Thu Jan 1 00:23:17 1970 kern.info kernel: [ 1397.470000] usb 1-1: new high-speed USB device number 6 using ehci-platform
Thu Jan 1 00:23:17 1970 kern.info kernel: [ 1397.630000] hub 1-1:1.0: USB hub found
Thu Jan 1 00:23:17 1970 kern.info kernel: [ 1397.630000] hub 1-1:1.0: 4 ports detected

connecting arduino to hub

Thu Jan 1 00:23:31 1970 kern.info kernel: [ 1411.940000] usb 1-1.4: new full-speed USB device number 7 using ehci-platform
Thu Jan 1 00:23:32 1970 kern.info kernel: [ 1412.060000] cdc_acm 1-1.4:1.0: ttyACM0: USB ACM device

disconnecting hub, with arduino

Thu Jan 1 00:24:50 1970 kern.info kernel: [ 1490.540000] usb 1-1: USB disconnect, device number 6
Thu Jan 1 00:24:50 1970 kern.info kernel: [ 1490.540000] usb 1-1.4: USB disconnect, device number 7

connecting hub with arduino

Thu Jan 1 00:26:04 1970 kern.info kernel: [ 1564.760000] usb 1-1: new high-speed USB device number 8 using ehci-platform
Thu Jan 1 00:26:04 1970 kern.info kernel: [ 1564.920000] hub 1-1:1.0: USB hub found
Thu Jan 1 00:26:04 1970 kern.info kernel: [ 1564.920000] hub 1-1:1.0: 4 ports detected
Thu Jan 1 00:26:05 1970 kern.info kernel: [ 1565.210000] usb 1-1.4: new full-speed USB device number 9 using ehci-platform
Thu Jan 1 00:26:05 1970 kern.info kernel: [ 1565.330000] cdc_acm 1-1.4:1.0: ttyACM0: USB ACM device

So we could for example look for the latest new full-speed USB device and check if 1-1.4 instead of 1-1 is before that.

Thu Jan 1 00:22:21 1970 kern.info kernel: [ 1341.320000] usb 1-1: new full-speed USB device number 5 using ehci-platform

vs:

Thu Jan 1 00:26:05 1970 kern.info kernel: [ 1565.210000] usb 1-1.4: new full-speed USB device number 9 using ehci-platform

woutgg commented 11 years ago

This information can be found in the form of a directory tree in /sys/devices/platform/ehci-platform/usb1/1-1 (where usb1 is the so called 'root hub' and 1-1 is the device connected to the wifibox's usb port). If the connected device is a hub and a printer is connected to it, this will be nested another level deeper.

The tree contains a lot of dynamic files as well, describing the device at hand. For instance: the file speed will be 12 for a printer and 480 for a high-speed hub. This could be a first method of hub-detection (albeit a bit naive).