I've a USB bluetooth dongle

root@maiko-cce-lin:~# lsusb | grep Bluetooth
Bus 001 Device 007: ID 0a12:0001 Cambridge Silicon Radio, Ltd Bluetooth Dongle (HCI mode)

that isn't working properly, hardly-ever it works but stops working in my next reboot.

what I've tried

it isn't software blocked

root@maiko-cce-lin:~# rfkill list
0: phy0: Wireless LAN
    Soft blocked: no
    Hard blocked: no
1: hci0: Bluetooth
    Soft blocked: no
    Hard blocked: no

my device is recognized by hciconfig

root@maiko-cce-lin:~# hciconfig -a
hci0:   Type: BR/EDR  Bus: USB
    BD Address: 00:1F:81:00:01:1C  ACL MTU: 1021:4  SCO MTU: 180:1
    DOWN 
    RX bytes:330 acl:0 sco:0 events:8 errors:0
    TX bytes:24 acl:0 sco:0 commands:30 errors:22
    Features: 0xff 0x3e 0x09 0x76 0x80 0x01 0x00 0x80
    Packet type: DM1 DM3 DM5 DH1 DH3 DH5 HV1 HV2 HV3 
    Link policy: 
    Link mode: SLAVE ACCEPT 

but I can't turn on my hci interface

root@maiko-cce-lin:~# hciconfig hci up
Can't init device hci0: Connection timed out (110)

I don't understand why.. the hcitool command doesn't show any device.

root@maiko-cce-lin:~# hcitool dev
Devices:

I've tried to restart my bluetooth service too with this command and make all these previous commands again but without success.

root@maiko-cce-lin:~# service bluetooth restart
 * Stopping bluetooth                                                    [ OK ] 
 * Starting bluetooth                                                    [ OK ] 
root@maiko-cce-lin:~# 

The dongle works if you disconnect it from usb, wait a few seconds and connect it again. so there must be better solution for it ( a solution not involving physically removing the dongle!)