On Sun, 3 Mar 2019 22:46:20 +0000 living proof <
livingproof@live.de> wrote:
> for as well stretch-backports does not fix the problem
>
[ 2.574742] Bluetooth: hci0: rtl: loading rtl_bt/rtl8821a_config.bin
[ 2.575137] bluetooth hci0: firmware: failed to load rtl_bt/rtl8821a_config.bin (-2)
[ 2.575143] bluetooth hci0: Direct firmware load for rtl_bt/rtl8821a_config.bin failed with error -2
[ 2.575145] Bluetooth: hci0: Failed to load rtl_bt/rtl8821a_config.bin
copying rtl8723a_config.bin from https://github.com/lwfinger/rtl8723au_bt/ to /lib/firmware/rtl_bt/ does NOT solve the issue. You are actually pointing to a config file for a completly different device.
We are using the rtl8821a this config file is for the rtl8723au_bt...
Good evening.
I was fighting with this problem (Direct firmware load for rtl_bt/rtl8821a_config.bin failed with error -2) for some time. In /lib/firmware/rtl_bt/ directory I found that indeed this file has a
problem to load because this file does not even exist. For some reason only one file is present, rtl8821a_fw.bin, where another device has two (rtl8821c_config.bin and rtl8821c_fw.bin):
ls -al /lib/firmware/rtl_bt
...
-rw-r--r-- 1 root root 40520 Aug 23 02:04 rtl8812ae_fw.bin
-rw-r--r-- 1 root root 37420 Aug 23 02:04 rtl8821a_fw.bin
-rw-r--r-- 1 root root 10 Aug 23 02:04 rtl8821c_config.bin
-rw-r--r-- 1 root root 37356 Aug 23 02:04 rtl8821c_fw.bin
...
I had package firmware-realtek installed in newest version, so I downloaded .deb package from Debian webpage (https://packages.debian.org/buster-backports/firmware-realtek). Browsing it as
archive I found that file rtl_bt/rtl8821a_config.bin is also absent, for unknown to me reason.
Then I started looking for this file in other releases (sid and bullseye), with no positive result. I visited Realtek webpage, only to find that they have drivers only for Windows for this
device. Digging further, on address https://patchwork.ozlabs.org/patch/952071/ , I discovered following note about some Realtek devices:
> The Bluetooth parts of RTL8723D and RTL8723B share the same lmp
> subversion, thus we need to check both lmp subversion and hci revision
> to distinguish the two. The same situation is true for RTL8821A and
> RTL8821C. Accordingly, the selection code is revised.
> To improve maintainability, a new id_table struct is defined, and an
> array of such structs is constructed. Adding a new device can thus be
> as simple as adding another value to the table.
With lack of luck in my quest to find rtl8821a_config.bin file for Debian Buster I decided to try a crazy idea: duplicate rtl8821c_config.bin file and rename duplication on rtl8821a_config.bin.
-rw-r--r-- 1 root root 40520 Aug 23 02:04 rtl8812ae_fw.bin
-rw-r--r-- 1 root root 10 Feb 5 17:11 rtl8821a_config.bin
-rw-r--r-- 1 root root 37420 Aug 23 02:04 rtl8821a_fw.bin
-rw-r--r-- 1 root root 10 Aug 23 02:04 rtl8821c_config.bin
-rw-r--r-- 1 root root 37356 Aug 23 02:04 rtl8821c_fw.bin
If both devices are so similar, maybe providing fake rtl8821a_config.bin file will do the trick. After restart I I used dmesg and checked logs:
[ 26.389532] Bluetooth: hci0: RTL: rtl: examining hci_ver=06 hci_rev=000a lmp_ver=06 lmp_subver=8821
[ 26.390623] Bluetooth: hci0: RTL: rom_version status=0 version=1
[ 26.390624] Bluetooth: hci0: RTL: rtl: loading rtl_bt/rtl8821a_fw.bin
[ 26.392597] bluetooth hci0: firmware: direct-loading firmware rtl_bt/rtl8821a_fw.bin
[ 26.392605] Bluetooth: hci0: RTL: rtl: loading rtl_bt/rtl8821a_config.bin
[ 26.392748] bluetooth hci0: firmware: direct-loading firmware rtl_bt/rtl8821a_config.bin
[ 26.392757] Bluetooth: hci0: RTL: cfg_sz 10, total sz 17438
Well, it looked promising. I installed some additional Bluetooth-related packages (blueman, bluewho and entire family of bluez; bluetooth and bluez were installed earlier) and then I
launched Bluetooth Manager. It turns out that program not only detected Bluetooth device on my laptop but also I was able to send files between my laptop and my Nokia mobile on both
directions. I paired successfully both devices, but because lack of Bluetooth speakers I do not know if it is possible to play music via Bluetooth. It should be, I hope.
So, my "solution" seems to work, at least for me. But may I ask the question why file named rtl8821a_config.bin is not present in the firmware-realtek package? It does not exist at all or was
removed for some reason?
Also my method is nasty, I know about it, but if anyone will solve his/her problem by it, I will be happy.
With kindest regards,
Oliwia