Bluetooh issues and "solutions"

[steph68]

Hello,

I have some trouble (Mint 19) with my a dell embedded bluetooth card (which doesn't occurs with external bluetooth dongle), the process systemd-udev related to this device consume all the cpu.
I read several things and one seems a consistent analysis.

From https://askubuntu.com/questions/1028883 ... -with-wifi
As I understand, before all hardware is discovered properly, bind/unbind start executing when no procedures are available and it does not get reinitialized. After stopping and starting, it gets all the procedures in place. Probably, it is booting sequence problem.

Solution is to restart some services:

sudo systemctl stop systemd-udevd systemd-udevd-kernel.socket systemd-udevd-control.socket
sudo systemctl start systemd-udevd systemd-udevd-kernel.socket systemd-udevd-control.socket

Could it be possible to :

• delay the startup of these services? how ? when ?

• execute these command later in the startup process (workaround) ?

Considering these analysis is correct, I suppose the usb card where I plug the external bluetooth dongle is started later. Does someone know how it's done ?


thanks for your help.

[steph68]

Hello,

I had and have several troubles with bluetooth on my Dell laptop and it seems applicable to many computers and kind of devices. I'm a real newbies on this kind of low level Linux topics, feel free to explain why these things work, what they mean, I love to understand...

Issue 1: systemd-udev consume 100% of a core CPU
Workaround:
https://askubuntu.com/questions/1028883 ... -with-wifi

sudo systemctl stop systemd-udevd systemd-udevd-kernel.socket systemd-udevd-control.socket
sudo systemctl start systemd-udevd systemd-udevd-kernel.socket systemd-udevd-control.socket

A solution:
Edit /lib/udev/rules.d/97-hid2hci.rules file and add this ACTION=="add", in front of the corresponding line :

ACTION=="add", ATTR{bInterfaceClass}=="03", ATTR{bInterfaceSubClass}=="01", ATTR{bInterfaceProtocol}=="02", \
ATTRS{bDeviceClass}=="00", ATTRS{idVendor}=="413c", ATTRS{bmAttributes}=="e0", \
RUN+="hid2hci --method=dell --devpath=%p", ENV{HID2HCI_SWITCH}="1"

Issue 2: can't pair a device, (connection failed)
Workaround (same as previous):
Post start:

sudo systemctl stop systemd-udevd systemd-udevd-kernel.socket systemd-udevd-control.socket
sudo systemctl start systemd-udevd systemd-udevd-kernel.socket systemd-udevd-control.socket

Issue 3:
Everything works fine with external USB dongle, with Mint 19 out of the box. Then devices works on internal bluetooth card wihtout issue 2 or issue 4.

Issue 4: Device doesn't stay connected
I use bluetoothctl to pair the device with the command line.

Thanks.

[JeremyB]

This only applies to a small number of bluetooth devices used on Dell computers, can you post lsusb results so people may have an idea of this actually applies?

[steph68]

Hello,

Here is the result of lsusb command:
Bus 002 Device 004: ID 413c:2513 Dell Computer Corp. internal USB Hub of E-Port Replicator
Bus 002 Device 003: ID 413c:2513 Dell Computer Corp. internal USB Hub of E-Port Replicator
Bus 002 Device 002: ID 8087:0020 Intel Corp. Integrated Rate Matching Hub
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 003 Device 002: ID 046d:c52f Logitech, Inc. Unifying Receiver
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 005: ID 0a5c:5800 Broadcom Corp. BCM5880 Secure Applications Processor
Bus 001 Device 004: ID 05ca:1815 Ricoh Co., Ltd
Bus 001 Device 003: ID 413c:8185 Dell Computer Corp. Gobi 2000 Wireless Modem (QDL mode)
Bus 001 Device 002: ID 8087:0020 Intel Corp. Integrated Rate Matching Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub