Setting Inquiry Transmit Power Level

Dear list,

I'm facing the same problem that Natale Vinto mentioned nearly a year ago [1] on this list. I'm trying to set the Inquiry Transmit Power Level of a Belkin USB Bluetooth adapter, unfortunately without much of success.

It is a Bluetooth 2.1 capable device as mentioned by hciconfig:

# hciconfig hci0 version
hci0:   Type: BR/EDR  Bus: USB
        BD Address: 00:19:0E:08:62:EC  ACL MTU: 1021:8  SCO MTU: 64:1
        HCI Version: 2.1 (0x4)  Revision: 0x5184
        LMP Version: 2.1 (0x4)  Subversion: 0x420e
        Manufacturer: Broadcom Corporation (15)
# hciconfig hci0 revision
hci0:   Type: BR/EDR  Bus: USB
        BD Address: 00:19:0E:08:62:EC  ACL MTU: 1021:8  SCO MTU: 64:1
        Firmware 132.66 / 14

Writing the inqtpl is supported, as shown by 'hciconfig hci0 commands'.

However:

# hciconfig hci0 inqtpl
hci0:   Type: BR/EDR  Bus: USB
        BD Address: 00:19:0E:08:62:EC  ACL MTU: 1021:8  SCO MTU: 64:1
        Inquiry transmit power level: 0
# hciconfig hci0 inqtpl 4
# hciconfig hci0 inqtpl  
hci0:   Type: BR/EDR  Bus: USB
        BD Address: 00:19:0E:08:62:EC  ACL MTU: 1021:8  SCO
        MTU: 64:1
        Inquiry transmit power level: 0

All this happens with Bluez 4.70 (the one from Debian unstable) on a (pretty much plain upstream) 2.6.32.22 kernel.

I'd like to hear from you if this is a hardware or firmware issue of the adapter/chip (in which case I suspect it can't be fixed and I need to find another adapter which isn't broken), or whether it can be a Bluez issue.

[1] http://www.spinics.net/lists/linux-bluetooth/msg03785.html

Thanks very much for your time.

Have a nice day,

Roel Huybrechts

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