APPLIED[Unstable]: [SRU] [F/G/Unstable/OEM-5.6] [PATCH 0/2] Ask 8821C Bluetooth controller to drop old firmware

Seth Forshee seth.forshee at canonical.com
Fri Dec 18 23:04:51 UTC 2020


On Sat, Nov 14, 2020 at 12:15:50AM +0800, Kai-Heng Feng wrote:
> BugLink: https://bugs.launchpad.net/bugs/1904221
> 
> [Impact]
> Some platforms may keep USB power in S3/S4/S5, so Realtek 8821C retains
> its firmware even with a cold boot.
> 
> [Fix]
> Use vendor command to drop firmware if the version is old.
> 
> [Test case]
> Use dmesg to check if new firmware is loaded.
> With the patch applied, we can find new firmware is loaded.
> 
> [Where problems could occur]
> There's a 200ms delay which can slow down when BT controller is opened
> by userspace first time.

Applied to unstable/master, thanks!



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