Re: Enabling continuous LE Active scan in 5.32?

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Fri, Jul 31, 2015 at 8:06 AM, Arun K. Singh <arunkat@xxxxxxxxx> wrote:
> Hi Jakub,
>
>>> Checking adapter.c, adapter->no_scan_restart_delay parameter looks
>>> promising if set to true. Still same result - next scan delay ~ 2 sec.
>>> Not sure if such delay is intentional or platform performance related
>>> My question is :- Is there a neat way to trigger continuous active LE
>>> scan even though it may sound power-wise inefficient. Tried to grep
>>> archives but couldn't find much help.
>> So there is something like that, but you'll probably have to update
>> your kernel (I think this feature is all in 4.0, or 4.1)
>> Recently kernel patch landed that enables simultaneous discovery, but
>> that works only for some controllers, you'll have to check wether your
>> controller have this quirk set: HCI_QUIRK_SIMULTANEOUS_DISCOVERY
>> http://git.kernel.org/cgit/linux/kernel/git/bluetooth/bluetooth-next.git/tree/include/net/bluetooth/hci.h#n164
>> What this does is: previously there was 5s le scan, then 5s classic
>> scan, then 5s break, now it's simulteanous le and br/edr scan.
>
> Thanks for the insight. But I am more interested in reducing the 5s
> break aka IDLE_DISCOV_TIMEOUT to zero.
> It is when I reduce this to zero or set adapter->no_scan_restart_delay
> parameter to True that I still find few
> seconds delay to restart scan. I have taken care of interleaved stuff
> by setting my device  to "le" only in main.conf.
> So all my scans are "le only" for 10 seconds.  Do you think it is
> entire possible to make scan continuous for say a minute'
> without any restart delay.

It sounds like a bug, maybe something platform or controller
dependent. It's working fine for me now on x64 platform with intel or
CSR controllers and latest kernel. Can you try running bluetoothd with
-nd flags (show debugging output + stay running in console) to gather
some logs ?
Also runing monitor/btmon at same time might be useful to see what's
going to controller.

>
> Thanks,
> Arun
--
To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html



[Index of Archives]     [Bluez Devel]     [Linux Wireless Networking]     [Linux Wireless Personal Area Networking]     [Linux ATH6KL]     [Linux USB Devel]     [Linux Media Drivers]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [Big List of Linux Books]

  Powered by Linux