Re: [PATCH 4/4] ASoC: fsl_easrc: expose individual DAIs per conversion context

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [High] Concurrent streams will cause a data race on the shared `dma_params_tx` and `dma_params_rx` structures, leading to incorrect DMA FIFO address configuration and state corruption.
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--- Patch [4]: [PATCH 4/4] ASoC: fsl_easrc: expose individual DAIs per conversion context ---
commit 8f522766ccdfc101a1c60ab6f34e2623d03f39d0
Author: Shengjiu Wang <shengjiu.wang@nxp.com>

ASoC: fsl_easrc: expose individual DAIs per conversion context

The i.MX EASRC hardware supports four independent conversion contexts
(A, B, C, D). The driver previously registered a single DAI with generic
stream names "ASRC-Playback" and "ASRC-Capture", which prevents
individual contexts from being routed to separate audio paths
simultaneously. This commit replaces the single fsl_easrc_dai instance 
with an array of four DAI drivers.

> diff --git a/sound/soc/fsl/fsl_easrc.c b/sound/soc/fsl/fsl_easrc.c
> index 15a3424967601..dd0c3046a0075 100644
> --- a/sound/soc/fsl/fsl_easrc.c
> +++ b/sound/soc/fsl/fsl_easrc.c

[ ... ]

> @@ -2245,7 +2317,7 @@ static int fsl_easrc_probe(struct platform_device *pdev)
>  	regcache_cache_only(easrc->regmap, true);
>  
>  	ret = devm_snd_soc_register_component(dev, &fsl_easrc_component,
> -					      &fsl_easrc_dai, 1);
> +					      fsl_easrc_dai, ARRAY_SIZE(fsl_easrc_dai));

[Severity: High]
When multiple DAIs are registered and active concurrently, can this cause a
data race on the shared DMA parameters?

Since all four DAIs share the same operations, fsl_easrc_dai_probe()
initializes them all with the exact same pointers:

fsl_easrc_dai_probe() {
    ...
    snd_soc_dai_init_dma_data(cpu_dai,
                              &easrc->dma_params_tx,
                              &easrc->dma_params_rx);
    ...
}

If an application opens multiple PCM devices simultaneously, won't their
concurrent hardware parameters operations modify the shared parameters
without locking?

fsl_asrc_dma_hw_params() {
    ...
    dma_params_fe = snd_soc_dai_get_dma_data(snd_soc_rtd_to_cpu(rtd, 0), substream);
    dma_params_fe->addr = asrc->paddr + asrc->get_fifo_addr(!dir, index);
    dma_params_fe->maxburst = dma_params_be->maxburst;
    ...
}

Could this lead to incorrect DMA FIFO address configuration and state corruption
across the different DAI contexts?

>  	if (ret) {
>  		dev_err(dev, "failed to register ASoC DAI\n");
>  		goto err_pm_disable;

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260720095450.1618747-1-shengjiu.wang@oss.nxp.com?part=4