Re: [PATCH] mwifiex: Ignore BTCOEX events from the 88W8897 firmware
From: Bjorn Helgaas <helgaas@kernel.org>
Date: 2021-11-29 23:38:32
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On Mon, Nov 29, 2021 at 05:32:11PM -0600, Bjorn Helgaas wrote:
On Wed, Nov 03, 2021 at 09:58:27PM +0100, Jonas Dreßler wrote:quoted
The firmware of the 88W8897 PCIe+USB card sends those events very unreliably, sometimes bluetooth together with 2.4ghz-wifi is used and no COEX event comes in, and sometimes bluetooth is disabled but the coexistance mode doesn't get disabled.s/sends those events/sends BTCOEX events/ so it reads well without the subject. s/coexistance/coexistence/ Is BTCOEX a standard Bluetooth thing? Is there a spec reference that could be useful here? I've never seen those specs, so this is just curiosity. I did download the "Bluetooth Core Spec v5.3", which does have a "Wireless Coexistence Signaling and Interfaces" chapter, but "BTCOEX" doesn't appear in that doc.quoted
This means we sometimes end up capping the rx/tx window size while bluetooth is not enabled anymore, artifically limiting wifi speeds even though bluetooth is not being used.s/artifically/artificially/quoted
Since we can't fix the firmware, let's just ignore those events on the 88W8897 device. From some Wireshark capture sessions it seems that the Windows driver also doesn't change the rx/tx window sizes when bluetooth gets enabled or disabled, so this is fairly consistent with the Windows driver.
I hadn't read far enough to see that the patch was already applied, sorry for the noise :)