Problem with booting & udev rules

[Miguel Ángel]

Hi!

I have a USB converter connected and I wrote the udev rules so you always had the same name. However, there are times in the boot the system does not give the same names to the Sierra modem. Apparently the system finds the USB converter while charging the modem and temporarily retains some names.

The correct case is this (dmesg output):

sierra 1-1:1.0: Sierra USB modem converter detected

usb 1-1: APM supported, enabling autosuspend.

usb 1-1: Sierra USB modem converter now attached to ttyUSB0

sierra 1-1:1.1: Sierra USB modem converter detected

usb 1-1: APM supported, enabling autosuspend.

usb 1-1: Sierra USB modem converter now attached to ttyUSB1

sierra 1-1:1.2: Sierra USB modem converter detected

usb 1-1: APM supported, enabling autosuspend.

usb 1-1: Sierra USB modem converter now attached to ttyUSB2

sierra 1-1:1.3: Sierra USB modem converter detected

usb 1-1: APM supported, enabling autosuspend.

usb 1-1: Sierra USB modem converter now attached to ttyUSB3

sierra 1-1:1.4: Sierra USB modem converter detected

usb 1-1: APM supported, enabling autosuspend.

usb 1-1: Sierra USB modem converter now attached to ttyUSB4

sierra 1-1:1.5: Sierra USB modem converter detected

usb 1-1: APM supported, enabling autosuspend.

usb 1-1: Sierra USB modem converter now attached to ttyUSB5

sierra 1-1:1.6: Sierra USB modem converter detected

usb 1-1: APM supported, enabling autosuspend.

usb 1-1: Sierra USB modem converter now attached to ttyUSB6

USB Serial support registered for FTDI USB Serial Device

ftdi_sio 1-2:1.0: FTDI USB Serial Device converter detected

usbcore: registered new interface driver sierra

usb 1-2: Detected FT232BM

usb 1-2: Number of endpoints 2

usb 1-2: Endpoint 1 MaxPacketSize 64

usb 1-2: Endpoint 2 MaxPacketSize 64

sierra: v.1.7.30:USB Driver for Sierra Wireless USB modems

usb 1-2: Setting MaxPacketSize 64

usb 1-2: FTDI USB Serial Device converter now attached to ttyUSB7

usbcore: registered new interface driver ftdi_sio

ftdi_sio: v1.5.0:USB FTDI Serial Converters Driver

The bad case is this (dmesg output):

sierra 1-1:1.0: Sierra USB modem converter detected

usb 1-1: APM supported, enabling autosuspend.

usb 1-1: Sierra USB modem converter now attached to ttyUSB0

sierra 1-1:1.1: Sierra USB modem converter detected

usb 1-1: APM supported, enabling autosuspend.

usb 1-1: Sierra USB modem converter now attached to ttyUSB1

sierra 1-1:1.2: Sierra USB modem converter detected

usb 1-1: APM supported, enabling autosuspend.

usb 1-1: Sierra USB modem converter now attached to ttyUSB2

sierra 1-1:1.3: Sierra USB modem converter detected

USB Serial support registered for FTDI USB Serial Device

usb 1-1: APM supported, enabling autosuspend.

ftdi_sio 1-2:1.0: FTDI USB Serial Device converter detected

usb 1-2: Detected FT232BM

usb 1-2: Number of endpoints 2

usb 1-1: Sierra USB modem converter now attached to ttyUSB4

usb 1-2: Endpoint 1 MaxPacketSize 64

usb 1-2: Endpoint 2 MaxPacketSize 64

usb 1-2: Setting MaxPacketSize 64

sierra 1-1:1.4: Sierra USB modem converter detected

usb 1-1: APM supported, enabling autosuspend.

usb 1-2: FTDI USB Serial Device converter now attached to ttyUSB3

usb 1-1: Sierra USB modem converter now attached to ttyUSB5

sierra 1-1:1.5: Sierra USB modem converter detected

usbcore: registered new interface driver ftdi_sio

usb 1-1: APM supported, enabling autosuspend.

ftdi_sio: v1.5.0:USB FTDI Serial Converters Driver

usb 1-1: Sierra USB modem converter now attached to ttyUSB6

sierra 1-1:1.6: Sierra USB modem converter detected

usb 1-1: APM supported, enabling autosuspend.

usb 1-1: Sierra USB modem converter now attached to ttyUSB7

usbcore: registered new interface driver sierra

sierra: v.1.7.30:USB Driver for Sierra Wireless USB modems

ls -l /dev output is (correct case):

crw-rw—- 1 root root 188, 0 Jan 30 16:39 ttyUSB0

crw-rw—- 1 root root 188, 1 Jan 30 16:40 ttyUSB1

lrwxrwxrwx 1 root root 11 Jan 30 16:39 ttyUSB10 -> usb_externo

crw-rw—- 1 root root 188, 2 Jan 30 16:39 ttyUSB2

crw-rw—- 1 root root 188, 3 Jan 30 16:39 ttyUSB3

crw-rw—- 1 root root 188, 4 Jan 30 16:39 ttyUSB4

crw-rw—- 1 root root 188, 6 Jan 30 16:40 ttyUSB6

crw-rw—- 1 root root 188, 7 Jan 30 16:39 ttyUSB7

-rw-r–r– 1 root root 19 Jan 30 16:39 udev_network_queue

crw-rw-rw- 1 root root 1, 9 Jan 30 16:39 urandom

crw-rw—- 1 root root 188, 5 Jan 30 16:40 usb_externo

ls -l /dev output is (bad case):

crw-rw—- 1 root root 188, 0 Jan 30 16:27 ttyUSB0

crw-rw—- 1 root root 188, 1 Jan 30 16:27 ttyUSB1

lrwxrwxrwx 1 root root 11 Jan 30 16:27 ttyUSB10 -> usb_externo

crw-rw—- 1 root root 188, 2 Jan 30 16:27 ttyUSB2

crw-rw—- 1 root root 188, 4 Jan 30 16:27 ttyUSB4

crw-rw—- 1 root root 188, 5 Jan 30 16:27 ttyUSB5

crw-rw—- 1 root root 188, 6 Jan 30 16:27 ttyUSB6

crw-rw—- 1 root root 188, 7 Jan 30 16:27 ttyUSB7

-rw-r–r– 1 root root 19 Jan 30 16:27 udev_network_queue

crw-rw-rw- 1 root root 1, 9 Jan 30 16:27 urandom

crw-rw—- 1 root root 188, 3 Jan 30 16:35 usb_externo

The udev rules is (name of file 99-proves.rules):

SUBSYSTEM==”tty”, ATTRS{idVendor}==”0403″, ATTRS{idProduct}==”6001″, NAME=”usb_externo”, SYMLINK+=”ttyUSB10″

What should I do for the Sierra modem provided by the same name?

[Jesse Gilles]

Hm, it looks like you did the right thing with the udev rule. Perhaps try changing the priority of your rule so it runs earlier?

Another option is to use the persistent serial dev names instead of /dev/ttyUSBX. Have a look in /dev/serial/by-id.

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