Re: [PATCH 1/4] ASoC: qcom: audioreach: compute active channel maps from channel_map

[Srinivas Kandagatla <srini@kernel.org>]

On 6/15/26 10:31 AM, Neil Armstrong wrote:
> On 6/15/26 10:38, Srinivas Kandagatla wrote:
>>
>>
>> On 6/10/26 8:41 AM, Neil Armstrong wrote:
>>> The Qualcom SM8650 based Ayaneo Pocket S2 gaming device has a set
>>> of 2 WSA speakers connected on the WSA2 lines.
>>>
>>> But the Audioreach DSP only handles WSA2 in pair with the WSA
>>> interface by using the upper bits of the active_channels_mask
>>> for WSA2 and the lower bits for WSA:
>>>
>>> /-------------------------------------------------\
>>> | Bits  |     3    |     2    |   1     |     0   |
>>> |-------------------------------------------------|
>>> | Line  | WSA2 Ch2 | WSA2 Ch1 | WSA Ch2 | WSA Ch1 |
>>> \-------------------------------------------------/
>>>
>> No, this is not totally correct, if the setup only has WSA2, then
>> channel 0 and 1 should be WSA2 channels.
>>
>> What is the backend dai id that is in DT, it should be
>>
>>     sound-dai = <&q6apmbedai WSA2_CODEC_DMA_RX_0>;
>>
>> I also noticed that you are using
>> https://github.com/linux-msm/audioreach-topology/blob/main/SM8550-HDK.m4
>> which has WSA as backend dai, that is not correct, you should have WSA2.
> 
> So I did try that, and DSP would error out when using the
> LPAIF_INTF_TYPE_WSA2,
> but I'm retrying from scratch right now.

Please share the failure logs, we need to change
1. dt : bedai id, codec dais with correct soundwire wsa2 instance, the
routes.
2. tplg


--srini
> 
> Thanks,
> Neil
> 
>>
>>
>>> Setting only the WSA2 upper bits is perfectly valid and
>>> functional but the current Audioreach code builds the bitmask
>>> from the channels count with:
>>>     active_channels_mask = (1 << num_channels) - 1;
>>>
>>> In order to enable the WSA2 bits the channel count should be 4,
>>> but the lower WSA bits are then also enabled and the DSP errors
>>> out when trying to play on the disabled WSA interface.
>>>
>>> A solution would've been to add a fake WSA2 topology element which
>>> would be translated into the top bits only, but it's not clean and
>>> add some special exceptions in the generic Audioreach code.
>>>
>>> The solution suggested by Srinivas is to use the channel mapping to
>>> set this bitmask.
>>>
>>> This works but makes all the other calls using the channel mapping fail
>>> because the DSP requires the channel_mapping table to start from index 0
>>> and using num_channel length in order to apply the mapping on the
>>> active_channels_mask bits in order.
>>>
>>> So we need to skip the empty channel mapping entries in all other
>>> users of the channel_map to build valid channel_mapping tables.
>>>
>>> This should not break any other usecases since the default channel
>>> mapping always start from index 0, and will add flexibilty to allow
>>> some special non linear mapping for other interfaces as well.
>>>
>>> Suggested-by: Srinivas Kandagatla <srinivas.kandagatla@oss.qualcomm.com>
>>> Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
>>> ---
>>>   sound/soc/qcom/qdsp6/audioreach.c | 47 ++++++++++++++++++++++++++++
>>> ++---------
>>>   1 file changed, 37 insertions(+), 10 deletions(-)
>>>
>>> diff --git a/sound/soc/qcom/qdsp6/audioreach.c b/sound/soc/qcom/
>>> qdsp6/audioreach.c
>>> index a13f753eff98..9b80cfa56e8a 100644
>>> --- a/sound/soc/qcom/qdsp6/audioreach.c
>>> +++ b/sound/soc/qcom/qdsp6/audioreach.c
>>> @@ -703,6 +703,7 @@ static int
>>> audioreach_codec_dma_set_media_format(struct q6apm_graph *graph,
>>>       int pm_sz = APM_HW_EP_PMODE_CFG_PSIZE;
>>>       int size = ic_sz + ep_sz + fs_sz + pm_sz;
>>>       void *p;
>>> +    int i;
>>>         struct gpr_pkt *pkt __free(kfree) =
>>> audioreach_alloc_apm_cmd_pkt(size, APM_CMD_SET_CFG, 0);
>>>       if (IS_ERR(pkt))
>>> @@ -741,7 +742,12 @@ static int
>>> audioreach_codec_dma_set_media_format(struct q6apm_graph *graph,
>>>         intf_cfg->cfg.lpaif_type = module->hw_interface_type;
>>>       intf_cfg->cfg.intf_index = module->hw_interface_idx;
>>> -    intf_cfg->cfg.active_channels_mask = (1 << cfg->num_channels) - 1;
>>> +    intf_cfg->cfg.active_channels_mask = 0;
>>> +    /* Convert the physical channel mapping into a bit field */
>>> +    for (i = 0; i < AR_PCM_MAX_NUM_CHANNEL; i++)
>>> +        if (cfg->channel_map[i])
>>> +            intf_cfg->cfg.active_channels_mask |= BIT(i);
>>> +
>>
>> This one looks good, this should be a bug fix patch.
>>
>>>       p += ic_sz;
>>>         pm_cfg = p;
>>> @@ -840,7 +846,7 @@ static int audioreach_mfc_set_media_format(struct
>>> q6apm_graph *graph,
>>>       uint32_t num_channels = cfg->num_channels;
>>>       int payload_size = APM_MFC_CFG_PSIZE(media_format, num_channels) +
>>>                   APM_MODULE_PARAM_DATA_SIZE;
>>> -    int i;
>>> +    int i, j;
>>>       void *p;
>>>         struct gpr_pkt *pkt __free(kfree) =
>>> audioreach_alloc_apm_cmd_pkt(payload_size, APM_CMD_SET_CFG, 0);
>>> @@ -860,8 +866,12 @@ static int
>>> audioreach_mfc_set_media_format(struct q6apm_graph *graph,
>>>       media_format->sample_rate = cfg->sample_rate;
>>>       media_format->bit_width = cfg->bit_width;
>>>       media_format->num_channels = cfg->num_channels;
>>> -    for (i = 0; i < num_channels; i++)
>>> -        media_format->channel_mapping[i] = cfg->channel_map[i];
>>> +    /* Convert the physical mapping to a logical mapping of the
>>> channels */
>>> +    for (i = 0, j = 0; i < AR_PCM_MAX_NUM_CHANNEL && j < cfg-
>>> >num_channels; i++) {
>>> +        if (!cfg->channel_map[i])
>>> +            continue;
>>> +        media_format->channel_mapping[j++] = cfg->channel_map[i];
>> Each element i of the channel_mapping[i] array, describes the channel i
>> inside the buffer where i is less than num_channels.  An unused channel
>> is set to 0.
>>
>> For some reason I get impression that user is trying to set a 4 channels
>> instead of 2 channel.
>>
>> Can you fix the backend-dai id and play it directly on WSA2 instead of
>> WSA.
>> Or was there a reason for not doing it otherwise?
>>
>> --srini
>>
>>> +    }
>>>         return q6apm_send_cmd_sync(graph->apm, pkt, 0);
>>>   }
>>> @@ -1080,6 +1090,7 @@ static int
>>> audioreach_pcm_set_media_format(struct q6apm_graph *graph,
>>>       struct apm_pcm_module_media_fmt_cmd *cfg;
>>>       struct apm_module_param_data *param_data;
>>>       int payload_size;
>>> +    int i, j;
>>>         if (num_channels > 4) {
>>>           dev_err(graph->dev, "Error: Invalid channels (%d)!\n",
>>> num_channels);
>>> @@ -1113,7 +1124,12 @@ static int
>>> audioreach_pcm_set_media_format(struct q6apm_graph *graph,
>>>       media_cfg->num_channels = mcfg->num_channels;
>>>       media_cfg->q_factor = mcfg->bit_width - 1;
>>>       media_cfg->bits_per_sample = mcfg->bit_width;
>>> -    memcpy(media_cfg->channel_mapping, mcfg->channel_map, mcfg-
>>> >num_channels);
>>> +    /* Convert the physical mapping to a logical mapping of the
>>> channels */
>>> +    for (i = 0, j = 0; i < AR_PCM_MAX_NUM_CHANNEL && j < mcfg-
>>> >num_channels; i++) {
>>> +        if (!mcfg->channel_map[i])
>>> +            continue;
>>> +        media_cfg->channel_mapping[j++] = mcfg->channel_map[i];
>>> +    }
>>>         return q6apm_send_cmd_sync(graph->apm, pkt, 0);
>>>   }
>>> @@ -1127,6 +1143,7 @@ static int
>>> audioreach_shmem_set_media_format(struct q6apm_graph *graph,
>>>       struct payload_media_fmt_pcm *cfg;
>>>       struct media_format *header;
>>>       int rc, payload_size;
>>> +    int i, j;
>>>       void *p;
>>>         if (num_channels > 4) {
>>> @@ -1166,7 +1183,12 @@ static int
>>> audioreach_shmem_set_media_format(struct q6apm_graph *graph,
>>>           cfg->q_factor = mcfg->bit_width - 1;
>>>           cfg->endianness = PCM_LITTLE_ENDIAN;
>>>           cfg->num_channels = mcfg->num_channels;
>>> -        memcpy(cfg->channel_mapping, mcfg->channel_map, mcfg-
>>> >num_channels);
>>> +        /* Convert the physical mapping to a logical mapping of the
>>> channels */
>>> +        for (i = 0, j = 0; i < AR_PCM_MAX_NUM_CHANNEL && j < cfg-
>>> >num_channels; i++) {
>>> +            if (!mcfg->channel_map[i])
>>> +                continue;
>>> +            cfg->channel_mapping[j++] = mcfg->channel_map[i];
>>> +        }
>>>       } else {
>>>           rc = audioreach_set_compr_media_format(header, p, mcfg);
>>>           if (rc)
>>> @@ -1243,7 +1265,7 @@ static int
>>> audioreach_speaker_protection_vi(struct q6apm_graph *graph,
>>>       struct apm_module_sp_vi_ex_mode_cfg *ex_cfg;
>>>       int op_sz, cm_sz, ex_sz;
>>>       struct apm_module_param_data *param_data;
>>> -    int rc, i, payload_size;
>>> +    int rc, i, payload_size, j;
>>>       struct gpr_pkt *pkt;
>>>       void *p;
>>>   @@ -1284,14 +1306,19 @@ static int
>>> audioreach_speaker_protection_vi(struct q6apm_graph *graph,
>>>       param_data->param_size = cm_sz - APM_MODULE_PARAM_DATA_SIZE;
>>>         cm_cfg->cfg.num_channels = num_channels * 2;
>>> -    for (i = 0; i < num_channels; i++) {
>>> +    /* Convert the physical mapping to a logical mapping of the
>>> channels */
>>> +    for (i = 0, j = 0; i < AR_PCM_MAX_NUM_CHANNEL && j <
>>> num_channels; i++) {
>>> +        if (!mcfg->channel_map[i])
>>> +            continue;
>>>           /*
>>>            * Map speakers into Vsense and then Isense of each channel.
>>>            * E.g. for PCM_CHANNEL_FL and PCM_CHANNEL_FR to:
>>>            * [1, 2, 3, 4]
>>>            */
>>> -        cm_cfg->cfg.channel_mapping[2 * i] = (mcfg->channel_map[i] -
>>> 1) * 2 + 1;
>>> -        cm_cfg->cfg.channel_mapping[2 * i + 1] = (mcfg-
>>> >channel_map[i] - 1) * 2 + 2;
>>> +        cm_cfg->cfg.channel_mapping[2 * j] = (mcfg->channel_map[i] -
>>> 1) * 2 + 1;
>>> +        cm_cfg->cfg.channel_mapping[2 * j + 1] = (mcfg-
>>> >channel_map[i] - 1) * 2 + 2;
>>> +
>>> +        ++j;
>>>       }
>>>         p += cm_sz;
>>>
>>
>