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

Kai-Heng Feng kai.heng.feng at canonical.com
Fri Nov 13 16:15:50 UTC 2020


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.

Colin Ian King (1):
  Bluetooth: btrtl: fix incorrect skb allocation failure check

Kai-Heng Feng (1):
  Bluetooth: btrtl: Ask 8821C to drop old firmware

 drivers/bluetooth/btrtl.c | 46 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 46 insertions(+)

-- 
2.28.0




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