bluetooth adapter is not detected on Asus M51Sr if the asus-laptop package is configured not to turn the Bluetooth LED on startup

[Dmytro Lapshyn]

It appears that on my laptop (see below for hardware specs), if the system starts up with the Bluetooth LED turned off (the asus_laptop kernel mode is configured not to "touch" the LED by default), the Bluetooth adapter hardware is NOT detected at all. This, in turn, leads to inability to turn on the adapter by regular means, as neither the hardware rfkill switch, nor the Fn-F2 hotkey have any effect (they DO however both work for the WiFi adapter).

If I manually turn the LED on by typing the following command in the terminal:
sudo sh -c "echo '1' > /sys/devices/platform/asus_laptop/bluetooth"

then the hardware gets detected, works as expected and CAN be controlled by the rfkill interface.

According to the Wiki pages of the acpi4asus project, it _could_ be the case that the sysfs file for the LED also controls the power state of the adapter (which is being attributed to DSDT specifics). However, what I would NOT expect is that setting the adapter's power state to "DOWN" prevents the very detection of the adapter hardware - that is, I would expect that if the BT adapter is turned off, I can still see it in the hciconfig output, just marked as "DOWN".

Interestingly, on Windows 7, the Bluetooth adapter ALSO disappears from the Device Manager if turned off either via the Asus wireless tray utility or by the hardware rfkill switch. The difference is, though, that the proprietary utility somehow "knows" that the adapter is still present and can enable it.

OS Version:
Description: Ubuntu 11.04

Hardware:
Asus M51Sr Laptop

Custom module configuration:

/etc/modprobe.d/asus_laptop.conf:
options asus_laptop wapf=1 wlan_status=-1 bluetooth_status=-1

(tried different wapf values as per the acpi4asus "WAPF" Wiki page with no effect)

NOTE: The following info can be obtained ONLY if I forcibly turn on the BT adapter on by typing
  sudo sh -c "echo '1' > /sys/devices/platform/asus_laptop/bluetooth"
in the terminal:

ubuntu@ubuntu:~$ lsusb
Bus 007 Device 003: ID 0b05:1712 ASUSTek Computer, Inc. BT-183 Bluetooth 2.0+EDR adapter

ubuntu@ubuntu:~$ hciconfig -a hci0
hci0: Type: BR/EDR Bus: USB
...
 UP RUNNING
...
 Features: 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
 Packet type: DM1 DH1 HV1
 Link policy:
 Link mode: SLAVE ACCEPT
 Name: 'ASUS BT183'
 Class: 0x000000
 Service Classes: Unspecified
 Device Class: Miscellaneous,
 HCI Version: 2.0 (0x3) Revision: 0x77b
 LMP Version: 2.0 (0x3) Subversion: 0x77b
 Manufacturer: Cambridge Silicon Radio (10)

[Konrad Zapałowicz (kzapalowicz)]

This is reported against an old version of Ubuntu and many things has changed since then. Because of that we won't fix this issue however if this behavior repeats on a modern version please fill a bug report against it and we will take it from there.