On 4/10/24 3:00 PM, Wren Turkal wrote:
+Johan since he's a former BT drivers maintainer.
On 4/9/24 1:11 PM, Wren Turkal wrote:
On 4/9/24 1:03 PM, Luiz Augusto von Dentz wrote:
5.19 seems a little too old, imo, or has it been broken for that long,
did you at least tried with bluetooth-next? Try contacting the people
who actually wrote the driver.
Sorry, I didn't answer your question. Yes, I do think it's been broken
for longer than that, but I wanted to confirm.
Okay, so I tried 6.9-rc3 and every main release 5.19-6.8.
I have found the following:
* older kernels (6.3 and before) seem to be far less likely to kill on a
cycling the bluetooth service.
* 6.8/6.9-rcs consistently destroy bluetooth when stopping and
restarting the service
* If I destroy the bluetooth service with a BT service restart in
6.9-rc3 and warm reboot into any release back to 5.19, bluetooth does
not work
* cold boot works in all cases assuming I give the laptop about 5s
between power off/on
I just did another experiment on 6.9-rc3. I blacklisted relevant
bluetooth modules and then warm booted without the blacklist. I did this
for both the "bluetooth" and "btqca" modules. In both cases, I cold
booted with and appropriate "module_blacklist" kernel arg. After the
boot, I verified the module was not loaded. I then warm booted without
the blacklist, and the bluetooth works, so bluetooth only seems to fail
when the linux module code for closing the device is run before a warm boot.
So, I suspsect that the process of closing out the hardware may be
leaving it in a state that the reset cannot handle (and probably never
could handle).
I also found that qualcomm has docs here:
https://www.qualcomm.com/products/technology/wi-fi/fastconnect/fastconnect-6800#Documentation
However, I am not a member of a Qualcomm verified company (mentioned in
the doc links). Luiz, Marcel, or Johan, do you have any contacts that
might be able to help me in getting info about the technical docs for
this hardware? I would love to see if I can find any issues in how the
hardware is being reset.
As an independent dev, I don't even know what it takes to get that kind
of access. I would welcome any help here. Hey Qualcomm, are you hiring? :P
wt
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You're more amazing than you think!
