[BUG] Headset capture does not work with S16_LE format on IPC4-SDW platforms

[keqiaozhang]

Describe the bug
I was trying to enable alsabat test for headset capture on MTL platforms, I found that if I test capture with s16_le on MTL-SDW, the max peak always 99%-100%. The recorded wav is full of noise. But with same amixer settings, S32_LE works well. it can record the real data without noise. This issue should be a regression, but not sure how long it has existed.

Console output

arecord -Dhw:0,1 -f s16_le -r 48000  -c 2 test.wav -vvv -d 5
Recording WAVE 'test.wav' : Signed 16 bit Little Endian, Rate 48000 Hz, Stereo
Hardware PCM card 0 'sof-soundwire' device 1 subdevice 0
Its setup is:
  stream       : CAPTURE
  access       : RW_INTERLEAVED
  format       : S16_LE
  subformat    : STD
  channels     : 2
  rate         : 48000
  exact rate   : 48000 (48000/1)
  msbits       : 16
  buffer_size  : 16384
  period_size  : 4096
  period_time  : 85333
  tstamp_mode  : NONE
  tstamp_type  : MONOTONIC
  period_step  : 1
  avail_min    : 4096
  period_event : 0
  start_threshold  : 1
  stop_threshold   : 16384
  silence_threshold: 0
  silence_size : 0
  boundary     : 4611686018427387904
  appl_ptr     : 0
  hw_ptr       : 0
Max peak (8192 samples): 0x00007ff6 #################### 99%
Max peak (8192 samples): 0x00007ffc #################### 99%
Max peak (8192 samples): 0x00007ffe #################### 99%
Max peak (8192 samples): 0x00008000 #################### 100%
Max peak (8192 samples): 0x00007ffc #################### 99%
Max peak (8192 samples): 0x00007ffe #################### 99%
Max peak (8192 samples): 0x00007ffe #################### 99%
Max peak (8192 samples): 0x00007ff0 #################### 99%
Max peak (8192 samples): 0x00007ff2 #################### 99%
Max peak (8192 samples): 0x00008000 #################### 100%
Max peak (8192 samples): 0x00007ff8 #################### 99%
Max peak (8192 samples): 0x00007ff8 #################### 99%
Max peak (8192 samples): 0x00008000 #################### 100%
Max peak (8192 samples): 0x00008000 #################### 100%
....

To Reproduce
arecord -Dhw:0,1 -f s16_le -r 48000 -c 2 test.wav -vvv -d 5

Reproduction Rate
100%

Expected behavior
A clear and concise description of what you expected to happen.

Impact
What impact does this issue have on your progress (e.g., annoyance, showstopper)

Environment

1. Branch name and commit hash of the 2 repositories: sof (firmware/topology) and linux (kernel driver).
   • Kernel: {tip sof-dev}
   • SOF: {tip main}
2. Name of the topology file
   • Topology: {sof-mtl-rt711-4ch.tplg}
3. Name of the platform(s) on which the bug is observed.
   • Platform: {MTL-RVP-SDW}

[mszleszy]

@keqiaozhang during debugging of #6723
I've noticed that sw is doing bit conversion improperly when using sdw topology - Binding 32/32bit sink with 16/32bit source
that will cause glitches in captured data (confirmed in fw testing framework)

Are you able to check if it's not the same case?
I can help with that but I'll need ipc & payload logs

[bardliao]

@mszleszy It seems that we do 16/32 -> 16/16 conversion. Please see the log below and the full dmesg log is attached dmesg_sdw_s16_capture.txt.

[  337.592506] snd_sof:sof_ipc4_widget_setup: sof-audio-pci-intel-mtl 0000:00:1f.3: Create widget copier.host.10.1 instance 1 - pipe 10 - core 0
[  337.592527] snd_sof:sof_ipc4_log_header: sof-audio-pci-intel-mtl 0000:00:1f.3: ipc tx      : 0x40010004|0x10015: MOD_INIT_INSTANCE [data size: 84]
[  337.592916] snd_sof:sof_ipc4_log_header: sof-audio-pci-intel-mtl 0000:00:1f.3: ipc tx reply: 0x60000000|0x10015: MOD_INIT_INSTANCE
[  337.593122] snd_sof:sof_ipc4_log_header: sof-audio-pci-intel-mtl 0000:00:1f.3: ipc tx done : 0x40010004|0x10015: MOD_INIT_INSTANCE [data size: 84]
[  337.593166] Message payload: 00000000: 0000066f 00000180 000000c0 00000001
[  337.593184] Message payload: 00000010: 0000bb80 00000020 ffffff10 00000001
[  337.593201] Message payload: 00000020: 00000000 00001002 0000bb80 00000010
[  337.593215] Message payload: 00000030: ffffff10 00000001 00000000 00001002
[  337.593229] Message payload: 00000040: 00000000 00000100 00000180 00000001
[  337.593240] Message payload: 00000050: 00000000

Do you know the proper way to do the conversion?

[mszleszy]

@mszleszy It seems that we do 16/32 -> 16/16 conversion. Please see the log below and the full dmesg log is attached dmesg_sdw_s16_capture.txt.

[  337.592506] snd_sof:sof_ipc4_widget_setup: sof-audio-pci-intel-mtl 0000:00:1f.3: Create widget copier.host.10.1 instance 1 - pipe 10 - core 0
[  337.592527] snd_sof:sof_ipc4_log_header: sof-audio-pci-intel-mtl 0000:00:1f.3: ipc tx      : 0x40010004|0x10015: MOD_INIT_INSTANCE [data size: 84]
[  337.592916] snd_sof:sof_ipc4_log_header: sof-audio-pci-intel-mtl 0000:00:1f.3: ipc tx reply: 0x60000000|0x10015: MOD_INIT_INSTANCE
[  337.593122] snd_sof:sof_ipc4_log_header: sof-audio-pci-intel-mtl 0000:00:1f.3: ipc tx done : 0x40010004|0x10015: MOD_INIT_INSTANCE [data size: 84]
[  337.593166] Message payload: 00000000: 0000066f 00000180 000000c0 00000001
[  337.593184] Message payload: 00000010: 0000bb80 00000020 ffffff10 00000001
[  337.593201] Message payload: 00000020: 00000000 00001002 0000bb80 00000010
[  337.593215] Message payload: 00000030: ffffff10 00000001 00000000 00001002
[  337.593229] Message payload: 00000040: 00000000 00000100 00000180 00000001
[  337.593240] Message payload: 00000050: 00000000

Do you know the proper way to do the conversion?
@bardliao
Modules before are working on 32/32 and capture copier module is expecting16/32 on input. There is no module doing 32/32 to 16/32 conversion before.
I think this module should do conversion from 32/32 -> 16/16 conversion
payload would look something like that:

 00000000: 0000066f 00000180 000000c0 00000001
00000010: 0000bb80 00000020 ffffff10 00000001
00000020: 00000000 **00002002** 0000bb80 00000010
00000030: ffffff10 00000001 00000000 00001002
00000040: 00000000 00000100 00000180 00000001
00000050: 00000000

[bardliao]

Thanks @mszleszy
@keqiaozhang Could you test below change?

diff --git a/tools/topology/topology2/cavs-sdw.conf b/tools/topology/topology2/cavs-sdw.conf
index aa76bb35e5ab..ab768bb11a71 100644
--- a/tools/topology/topology2/cavs-sdw.conf
+++ b/tools/topology/topology2/cavs-sdw.conf
@@ -184,6 +184,7 @@ Object.Pipeline {
                                # 32 -> 16 bits conversion is done here,
                                # so in_bit_depth is 32 (and out_bit_depth is 16).
                                in_bit_depth    32
+                               in_valid_bit_depth      32
                        }
                }
        ]

[keqiaozhang]

Could you test below change?

@bardliao ,confirmed that above change can fix the issue on ADL. Please help to submit a PR.