Hi all, Sorry, I see that an identical patch has already been applied to bluetooth-next https://lore.kernel.org/linux-bluetooth/20250315022730.11071-1-hao.qin@xxxxxxxxxxxx/ While I'm glad the issue is being addressed, my original patch https://lore.kernel.org/linux-bluetooth/Z8ybV04CVUfVAykH@xxxxxxx/ contained useful context and tags that didn't make it into the final commit. For getting this fix into current kernel releases 6.12/6.13/6.14, I think the patch needs the "Cc: stable@xxxxxxxxxxxxxxx" tag that was in my original submission but missing from Hao's. Since this is causing significant issues for users on kernels 6.11+ (audio interfaces failing to work), it's important this gets backported. Hao, is this something you can do? I think the instructions at https://www.kernel.org/doc/html/v6.14/process/stable-kernel-rules.html#option-3 need to be followed, but I've not done this before. Thanks, Geoffrey. On Fri, Mar 28, 2025 at 07:22:06AM +1030, Geoffrey D. Bennett wrote: > This reverts commit ccfc8948d7e4d93cab341a99774b24586717d89a. > > The MediaTek Bluetooth controller reset that was added increases the > Bluetooth device setup time from ~200ms to ~20s and interferes with > other devices on the bus. > > Three users (with Focusrite Scarlett 2nd Gen 6i6 and 3rd Gen Solo and > 4i4 audio interfaces) reported that since 6.11 (which added this > commit) their audio interface fails to initialise if connected during > boot. Two of the users confirmed they have an MT7922. > > Errors like this are observed in dmesg for the audio interface: > > usb 3-4: parse_audio_format_rates_v2v3(): unable to find clock source (clock -110) > usb 3-4: uac_clock_source_is_valid(): cannot get clock validity for id 41 > usb 3-4: clock source 41 is not valid, cannot use > > The problem only occurs when both devices and kernel modules are > present and loaded during system boot, so it can be worked around by > connecting the audio interface after booting. > > Fixes: ccfc8948d7e4 ("Bluetooth: btusb: mediatek: reset the controller before downloading the fw") > Closes: https://github.com/geoffreybennett/linux-fcp/issues/24 > Bisected-by: Benedikt Ziemons <ben@rs485.network> > Tested-by: Benedikt Ziemons <ben@rs485.network> > Cc: stable@xxxxxxxxxxxxxxx > Signed-off-by: Geoffrey D. Bennett <g@xxxxx> > --- > Changelog: > > v1 -> v2: > > - Updated commit message with additional information. > - No change to this patch's diff. > - Dropped alternate patch that only reverted for 0x7922. > - Chris, Sean, Hao agreed to reverting the change: > https://lore.kernel.org/linux-bluetooth/2025031352-octopus-quadrant-f7ca@gregkh/T/#m0b31a9a8e87b9499e1ec3370c08f03e43bfb54bf > > drivers/bluetooth/btmtk.c | 10 ---------- > 1 file changed, 10 deletions(-) > > diff --git a/drivers/bluetooth/btmtk.c b/drivers/bluetooth/btmtk.c > index 68846c5bd4f7..4390fd571dbd 100644 > --- a/drivers/bluetooth/btmtk.c > +++ b/drivers/bluetooth/btmtk.c > @@ -1330,13 +1330,6 @@ int btmtk_usb_setup(struct hci_dev *hdev) > break; > case 0x7922: > case 0x7925: > - /* Reset the device to ensure it's in the initial state before > - * downloading the firmware to ensure. > - */ > - > - if (!test_bit(BTMTK_FIRMWARE_LOADED, &btmtk_data->flags)) > - btmtk_usb_subsys_reset(hdev, dev_id); > - fallthrough; > case 0x7961: > btmtk_fw_get_filename(fw_bin_name, sizeof(fw_bin_name), dev_id, > fw_version, fw_flavor); > @@ -1345,12 +1338,9 @@ int btmtk_usb_setup(struct hci_dev *hdev) > btmtk_usb_hci_wmt_sync); > if (err < 0) { > bt_dev_err(hdev, "Failed to set up firmware (%d)", err); > - clear_bit(BTMTK_FIRMWARE_LOADED, &btmtk_data->flags); > return err; > } > > - set_bit(BTMTK_FIRMWARE_LOADED, &btmtk_data->flags); > - > /* It's Device EndPoint Reset Option Register */ > err = btmtk_usb_uhw_reg_write(hdev, MTK_EP_RST_OPT, > MTK_EP_RST_IN_OUT_OPT); > -- > 2.45.0 > > >
