| Message ID | 20211103205827.14559-1-verdre@v0yd.nl (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 84d94e16efa268e4f2887d858cd67ee37b870f25 |
| Delegated to: | Kalle Valo |
| Headers | show |
| Series | mwifiex: Ignore BTCOEX events from the 88W8897 firmware | expand |
Jonas Dreßler <verdre@v0yd.nl> wrote: > 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. > > 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. > > 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. > > Signed-off-by: Jonas Dreßler <verdre@v0yd.nl> Patch applied to wireless-drivers-next.git, thanks. 84d94e16efa2 mwifiex: Ignore BTCOEX events from the 88W8897 firmware
On Wed, Nov 03, 2021 at 09:58:27PM +0100, Jonas Dreßler wrote: > 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. > 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/ > 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.
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: > > 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. > > > 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/ > > > 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 :)
On 30.11.21 00:38, Bjorn Helgaas wrote: > 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: >>> 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. >> >>> 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/ >> >>> 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 :) > No problem, in case you still want to know about BTCOEX: From what I've seen that's not something defined in any standards, but it's usually the name of the (sometimes patented) tricks every manufacturer has to make wifi and bt (which are both on the 2.4ghz band) behave well together. In almost every wifi driver you'll find functionality named btcoex/coexist/coexistence. The way it usually works is that the card sends an event to the kernel driver (in our case that event is called BTCOEX), and then the driver decides which quirks to apply to make wifi more interference-resistant (here's where the patents come in because some of those quirks are quite tricky, see for example https://patents.google.com/patent/US9226102B1/en). Now with our Marvell card the firmware is buggy and sends those events so unreliably (the card "forgets" to inform us that the BT connection has ended) that we're better off ignoring them.
diff --git a/drivers/net/wireless/marvell/mwifiex/main.h b/drivers/net/wireless/marvell/mwifiex/main.h index 90012cbcfd15..486315691851 100644 --- a/drivers/net/wireless/marvell/mwifiex/main.h +++ b/drivers/net/wireless/marvell/mwifiex/main.h @@ -1055,6 +1055,8 @@ struct mwifiex_adapter { void *devdump_data; int devdump_len; struct timer_list devdump_timer; + + bool ignore_btcoex_events; }; void mwifiex_process_tx_queue(struct mwifiex_adapter *adapter); diff --git a/drivers/net/wireless/marvell/mwifiex/pcie.c b/drivers/net/wireless/marvell/mwifiex/pcie.c index c3f5583ea70d..d5fb29400bad 100644 --- a/drivers/net/wireless/marvell/mwifiex/pcie.c +++ b/drivers/net/wireless/marvell/mwifiex/pcie.c @@ -3152,6 +3152,9 @@ static int mwifiex_init_pcie(struct mwifiex_adapter *adapter) if (ret) goto err_alloc_buffers; + if (pdev->device == PCIE_DEVICE_ID_MARVELL_88W8897) + adapter->ignore_btcoex_events = true; + return 0; err_alloc_buffers: diff --git a/drivers/net/wireless/marvell/mwifiex/sta_event.c b/drivers/net/wireless/marvell/mwifiex/sta_event.c index 68c63268e2e6..80e5d44bad9d 100644 --- a/drivers/net/wireless/marvell/mwifiex/sta_event.c +++ b/drivers/net/wireless/marvell/mwifiex/sta_event.c @@ -1058,6 +1058,9 @@ int mwifiex_process_sta_event(struct mwifiex_private *priv) break; case EVENT_BT_COEX_WLAN_PARA_CHANGE: dev_dbg(adapter->dev, "EVENT: BT coex wlan param update\n"); + if (adapter->ignore_btcoex_events) + break; + mwifiex_bt_coex_wlan_param_update_event(priv, adapter->event_skb); break;
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. 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. 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. Signed-off-by: Jonas Dreßler <verdre@v0yd.nl> --- drivers/net/wireless/marvell/mwifiex/main.h | 2 ++ drivers/net/wireless/marvell/mwifiex/pcie.c | 3 +++ drivers/net/wireless/marvell/mwifiex/sta_event.c | 3 +++ 3 files changed, 8 insertions(+)