On Tue, 2025-03-11 at 21:53 -0400, Luiz Augusto von Dentz wrote:
> Hi Chris, Sean, Hao,
>
> On Mon, Mar 10, 2025 at 5:24 PM Geraldo Nascimento
> <geraldogabriel@xxxxxxxxx> wrote:
> >
> > On Sun, Mar 09, 2025 at 06:02:11AM +1030, Geoffrey D. Bennett
> > wrote:
> > > This series (choose 1 of the 2 patches) addresses an issue where
> > > the
> > > MT7922 Bluetooth controller reset added in commit ccfc8948d7e4
> > > ("Bluetooth: btusb: mediatek: reset the controller before
> > > downloading
> > > the fw") is causing Focusrite USB audio devices to fail to
> > > initialise
> > > when connected during boot on kernels 6.11 and newer.
> > >
> > > Reported by three users here:
> > > https://github.com/geoffreybennett/linux-fcp/issues/24
> > >
> > > Two users confirmed they have an MT7922.
> > >
> > > I'm providing two possible solutions as I note there was a
> > > similar
> > > change made in commit a7208610761a ("Bluetooth: btmtk: Remove
> > > resetting mt7921 before downloading the fw"), so I'm not sure if
> > > the
> > > reset should be reverted for the MT7925 as well as the MT7922.
> > >
> > > Option 1: Revert the problematic reset behaviour entirely (MT7922
> > > +
> > > MT7925)
> > >
> > > Option 2: Remove the reset only for the MT7922
> > >
> > > Geoffrey D. Bennett (2):
> > >
> > > [PATCH 1/2] Revert "Bluetooth: btusb: mediatek: reset the
> > > controller
> > > before downloading the fw"
> > >
> > > [PATCH 2/2] Bluetooth: btmtk: Remove resetting mt7922 before
> > > downloading the fw
> > >
> > > --
> > > 2.45.0
> > >
> > >
> >
> > Hi Geoffrey,
> >
> > I understand there's no apparent nexus of causality here.
> >
> > However if three different users suddenly reported the same problem
> > and
> > the fix fixes it, we should take the report seriously and back down
> > on the problematic commit until we figure for sure what the heck is
> > going on.
> >
> > My bet is this is bona fide bug in the USB subsystem, but either
> > I'm not
> > looking hard enough or I'm looking into the wrong places, because
> > there's no way I can see in which way USB bluetooth driver from
> > MediaTek could cause clock detection to fail.
> >
> > No point in pressing this harder, but yeah, take the reports more
> > than
> > seriously, because if we don't understand in which way our own
> > (Linux)
> > code could be causing this, at least we should take cautionary
> > measures.
> >
> > In that sense, putting Takashi Iwai and Greg KH to Cc: in a modest
> > but
> > sincere belief that this issue is more than real, even though it
> > looks
> > like anticipated April 1st. Takashi can help with his expertise in
> > clock
> > detection and Greg could help pinpoint if this is indeed madness in
> > the
> > USB subsystem.
> >
> > Hope you and them don't mind the escalation :)
>
> Do you guys have any idea what could be possibly going on here? There
> really seems something is not right if one driver affects the other,
> especially if the devices are not actually related in any way.
>
>
Hello everyone,
I did the kernel bisection on this issue and tested Geoffrey's patches
since I own the affected combination of hardware and can reliably
reproduce the issue.
I was now able to capture both the sound device initialization failure
and the successful initialization from initramfs using the usbmon
module. One difference that is immediately noticeable is the amount of
URB_CONTROL data that is sent to the mediatek btusb device and a
considerable slow-down of the boot process (around 16s difference).
Following is some more information about the timing and other related
messages from the kernel message log. The first excerpt is from an
unpatched kernel 6.14.0-rc5:
[ 59.987242] lunar kernel: usb 1-2: new high-speed USB device number 2 using xhci_hcd
[ 59.987975] lunar kernel: usb 1-2: New USB device found, idVendor=1235, idProduct=8212, bcdDevice= 6.45
[ 59.988048] lunar kernel: usb 1-2: New USB device strings: Mfr=1, Product=3, SerialNumber=2
[ 59.988121] lunar kernel: usb 1-2: Product: Scarlett 4i4 USB
[ 59.988197] lunar kernel: usb 1-2: Manufacturer: Focusrite
[ 60.571193] lunar kernel: mt7921e 0000:0a:00.0: enabling device (0000 -> 0002)
[ 60.571314] lunar kernel: mt7921e 0000:0a:00.0: ASIC revision: 79220010
[ 60.571501] lunar kernel: usbcore: registered new interface driver btusb
[ 60.571513] lunar kernel: mt7921e 0000:0a:00.0: HW/SW Version: 0x8a108a10, Build Time: 20241106163228a
[ 60.571627] lunar kernel: mt7921e 0000:0a:00.0: WM Firmware Version: ____000000, Build Time: 20241106163310
[ 60.616673] lunar kernel: Bluetooth: hci0: HW/SW Version: 0x008a008a, Build Time: 20241106163512
[ 64.549017] lunar kernel: mt7921e 0000:0a:00.0 wlp10s0: renamed from wlan0
[ 70.700407] lunar kernel: usb 1-2: parse_audio_format_rates_v2v3(): unable to retrieve number of sample rates (clock 41)
[ 81.264360] lunar kernel: usb 1-2: parse_audio_format_rates_v2v3(): unable to retrieve number of sample rates (clock 41)
[ 81.264611] lunar kernel: usb 1-2: Focusrite Scarlett Gen 3 Mixer Driver enabled (pid=0x8212); report any issues to https://github.com/geoffreybennett/scarlett-gen2/issues
[ 81.264782] lunar kernel: usb 1-2: Error initialising Scarlett Gen 3 Mixer Driver: -71
[ 81.264903] lunar kernel: snd-usb-audio 1-2:1.0: probe with driver snd-usb-audio failed with error -71
[ 81.265040] lunar kernel: usb 1-2: Quirk or no altset; falling back to MIDI 1.0
[ 81.400030] lunar kernel: Bluetooth: hci0: Device setup in 20435397 usecs
[ 81.400114] lunar kernel: Bluetooth: hci0: HCI Enhanced Setup Synchronous Connection command is advertised, but not supported.
[ 81.680052] lunar kernel: Bluetooth: hci0: AOSP extensions version v1.00
[ 81.680170] lunar kernel: Bluetooth: hci0: AOSP quality report is supported
[ 87.373353] lunar kernel: usbcore: registered new interface driver snd-usb-audio
The following second excerpt is from the same kernel version with
Geoffrey's second patch applied:
[ 139.603887] lunar kernel: usb 1-2: new high-speed USB device number 2 using xhci_hcd
[ 139.604524] lunar kernel: usb 1-2: New USB device found, idVendor=1235, idProduct=8212, bcdDevice= 6.45
[ 139.604598] lunar kernel: usb 1-2: New USB device strings: Mfr=1, Product=3, SerialNumber=2
[ 139.604672] lunar kernel: usb 1-2: Product: Scarlett 4i4 USB
[ 139.604744] lunar kernel: usb 1-2: Manufacturer: Focusrite
[ 140.192488] lunar kernel: usbcore: registered new interface driver btusb
[ 140.192501] lunar kernel: mt7921e 0000:0a:00.0: enabling device (0000 -> 0002)
[ 140.192627] lunar kernel: Bluetooth: hci0: HW/SW Version: 0x008a008a, Build Time: 20241106163512
[ 140.192639] lunar kernel: mt7921e 0000:0a:00.0: ASIC revision: 79220010
[ 140.192753] lunar kernel: mt7921e 0000:0a:00.0: HW/SW Version: 0x8a108a10, Build Time: 20241106163228a
[ 140.192866] lunar kernel: mt7921e 0000:0a:00.0: WM Firmware Version: ____000000, Build Time: 20241106163310
[ 140.240011] lunar kernel: Bluetooth: hci0: Device setup in 188119 usecs
[ 140.240048] lunar kernel: Bluetooth: hci0: HCI Enhanced Setup Synchronous Connection command is advertised, but not supported.
[ 140.513341] lunar kernel: Bluetooth: hci0: AOSP extensions version v1.00
[ 140.513379] lunar kernel: Bluetooth: hci0: AOSP quality report is supported
[ 144.115475] lunar kernel: mt7921e 0000:0a:00.0 wlp10s0: renamed from wlan0
[ 144.115747] lunar kernel: usb 1-2: Focusrite Scarlett Gen 3 Mixer Driver enabled (pid=0x8212); report any issues to https://github.com/geoffreybennett/scarlett-gen2/issues
[ 144.115857] lunar kernel: usb 1-2: Firmware version 1605
[ 144.115954] lunar kernel: usb 1-2: Quirk or no altset; falling back to MIDI 1.0
[ 147.843340] lunar kernel: usbcore: registered new interface driver snd-usb-audio
Comparing the USB captures from the hub, filtered to just the first few
messages of the audio device yield the following exchanges. Again,
first the broken case:
No. Time Source Destination Protocol Length Info
7 0.011098 host 1.2.0 USB 64 GET DESCRIPTOR Request DEVICE
8 0.015218 1.2.0 host USB 82 GET DESCRIPTOR Response DEVICE
9 0.015272 host 1.2.0 USB 64 GET DESCRIPTOR Request CONFIGURATION
10 0.017966 1.2.0 host USB 73 GET DESCRIPTOR Response CONFIGURATION
11 0.018020 host 1.2.0 USB 64 GET DESCRIPTOR Request CONFIGURATION
12 0.025965 1.2.0 host USB 425 GET DESCRIPTOR Response CONFIGURATION
23 2.482241 host 1.2.0 USB 64 GET DESCRIPTOR Request STRING
24 2.484931 1.2.0 host USB 98 GET DESCRIPTOR Response STRING
25 2.484939 host 1.2.0 USB 64 GET DESCRIPTOR Request STRING
26 2.487916 1.2.0 host USB 84 GET DESCRIPTOR Response STRING
27 2.487941 host 1.2.0 USBAUDIO 65 SET CUR CX_CLOCK_SELECTOR_CONTROL request
2047 7.661154 1.2.0 host USBAUDIO 64 SET CUR CX_CLOCK_SELECTOR_CONTROL status
2048 7.661197 host 1.2.0 USBAUDIO 64 GET RANGE CS_SAM_FREQ_CONTROL request
4097 12.781553 1.2.0 host USBAUDIO 64 GET RANGE CS_SAM_FREQ_CONTROL[Malformed Packet]
The first discrepancy can be found in the URB status field of packet
no. 2047 (vs. 74 below) which is -2: No such file or directory (-
ENOENT).
In the second (following) case where the sound device initializes okay,
the URB status of the similar packet is Success (0) instead:
No. Time Source Destination Protocol Length Info
7 0.011565 host 1.2.0 USB 64 GET DESCRIPTOR Request DEVICE
8 0.015471 1.2.0 host USB 82 GET DESCRIPTOR Response DEVICE
9 0.015523 host 1.2.0 USB 64 GET DESCRIPTOR Request CONFIGURATION
10 0.018477 1.2.0 host USB 73 GET DESCRIPTOR Response CONFIGURATION
11 0.018537 host 1.2.0 USB 64 GET DESCRIPTOR Request CONFIGURATION
12 0.026331 1.2.0 host USB 425 GET DESCRIPTOR Response CONFIGURATION
23 4.168190 host 1.2.0 USB 64 GET DESCRIPTOR Request STRING
24 4.171031 1.2.0 host USB 98 GET DESCRIPTOR Response STRING
25 4.171040 host 1.2.0 USB 64 GET DESCRIPTOR Request STRING
26 4.174021 1.2.0 host USB 84 GET DESCRIPTOR Response STRING
27 4.174041 host 1.2.0 USBAUDIO 65 SET CUR CX_CLOCK_SELECTOR_CONTROL request
74 4.476033 1.2.0 host USBAUDIO 64 SET CUR CX_CLOCK_SELECTOR_CONTROL status
75 4.476050 host 1.2.0 USBAUDIO 64 GET CUR CX_CLOCK_SELECTOR_CONTROL request
76 4.479034 1.2.0 host USBAUDIO 65 GET CUR CX_CLOCK_SELECTOR_CONTROL response
77 4.479050 host 1.2.0 USBAUDIO 64 GET RANGE CS_SAM_FREQ_CONTROL request
202 4.582043 1.2.0 host USBAUDIO 66 GET RANGE CS_SAM_FREQ_CONTROL response
Please ask, if I should provide any more information or how and to whom
I can provide the full USB captures.
Thank you,
Ben
