'hcitool lescan' fails with 'Set scan parameters failed: Input/output error'

[Duncan Bayne]

I'm running Linux Mint 16 (Petra), 64-bit, Cinnamon. Kernel details are: 3.11.0-12-generic #19-Ubuntu SMP Wed Oct 9 16:20:46 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux.

Whenever I try to use hcitool to scan for my TI sensor tags, I receive the following error:

$ sudo hcitool lescan
Set scan parameters failed: Input/output error

This happens for the bluez version packaged with Petra, and if I build bluez from source (version 5.15).

I expect to see a list of available devices, like this (from http://mike.saunby.net/2013/04/raspberry-pi-and-ti-cc2541-sensortag.html):

LE Scan ...
90:59:AF:0A:A8:4E (unknown)
90:59:AF:0A:A8:4E SensorTag

[Duncan Bayne (dhgbayne)]

Oh, the device in question is a D-Link DBT-120:

$ lsusb
Bus 002 Device 003: ID 5986:03b4 Acer, Inc
Bus 002 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 003: ID 0a5c:217f Broadcom Corp. BCM2045B (BDC-2.1)
Bus 001 Device 007: ID 17f6:0310 Unicomp, Inc
Bus 001 Device 008: ID 07d1:fc01 D-Link System DBT-120 Bluetooth Adapter
Bus 001 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

$ hciconfig dev
hci0: Type: BR/EDR Bus: USB
        BD Address: 40:2C:F4:B5:74:1C ACL MTU: 1021:8 SCO MTU: 64:1
        UP RUNNING
        RX bytes:1004 acl:0 sco:0 events:47 errors:0
        TX bytes:692 acl:0 sco:0 commands:45 errors:0

[Kristian Andreas Vaksdal (vaksdal)]

Old bug report, but adding a comment here to help other people who turn up here looking for answers. The answer is that your bluetooth device is outdated and doesn't support BLE mode, so the lescan command fails.