USB device attached to different ttyUSB after resume from suspend to RAM
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
linux-lts-xenial (Ubuntu) |
Confirmed
|
Undecided
|
Unassigned |
Bug Description
Update: As for Xubuntu 11.04 at least, please read comment #13
OS: 8.10
USB device is attached to /dev/ttyUSB0 when I plug it in USB port. But when I suspend to RAM and resume, it gets attached to /dev/ttyUSB1. Consequently, the daemon configured using /dev/ttyUSB0 does not work after resume. I would expect the device to be attached to the same ttyUSB before and after.
Details of the device (from output of lsusb -v):
Bus 003 Device 010: ID 0403:6001 Future Technology Devices International, Ltd FT232 USB-Serial (UART) IC
Device Descriptor:
bLength 18
bDescriptorType 1
bcdUSB 2.00
bDeviceClass 0 (Defined at Interface level)
bDeviceSubClass 0
bDeviceProtocol 0
bMaxPacketSize0 8
idVendor 0x0403 Future Technology Devices International, Ltd
idProduct 0x6001 FT232 USB-Serial (UART) IC
bcdDevice 6.00
iManufacturer 1 FTDI
iProduct 2 FT232R USB UART
iSerial 3 A5001qxI
bNumConfigura
Configuration Descriptor:
bLength 9
bDescriptorType 2
wTotalLength 32
bNumInterfaces 1
bConfigurat
iConfiguration 0
bmAttributes 0xa0
(Bus Powered)
Remote Wakeup
MaxPower 90mA
Interface Descriptor:
bLength 9
bDescript
bInterfac
bAlternat
bNumEndpoints 2
bInterfac
bInterfac
bInterfac
iInterface 2 FT232R USB UART
Endpoint Descriptor:
bLength 7
Transfer Type Bulk
Synch Type None
Usage Type Data
bInterval 0
Endpoint Descriptor:
bLength 7
Transfer Type Bulk
Synch Type None
Usage Type Data
bInterval 0
Device Status: 0x0000
(Bus Powered)
Workaround is to run "/etc/init.d/lirc stop" before suspend and "/etc/init.d/lirc start" after resume; both as superuser. These can even be automated; see http:// en.opensuse. org/Pm- utils