Re: [PATCH 3/3] ASoC: qcom: q6prm: Keep the clock controller across DSP restarts

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential
issue to consider:
- [High] ASoC: qcom: q6prm: clock restore in prm_probe() times out
  before callback setup
--

commit 02c1625331bd9fcb6147637d9b08efb05abcc888
Author: Shawn Guo <shengchao.guo@oss.qualcomm.com>

ASoC: qcom: q6prm: Keep the clock controller across DSP restarts

This commit keeps the q6prm LPASS clock controller platform device alive
across DSP restarts and restores prepared clocks when the q6prm GPR device
probes again.

> diff --git a/sound/soc/qcom/qdsp6/q6prm.c b/sound/soc/qcom/qdsp6/q6prm.c
> index 73b5a96e83119..861d48bdb5eaf 100644
> --- a/sound/soc/qcom/qdsp6/q6prm.c
> +++ b/sound/soc/qcom/qdsp6/q6prm.c
[ ... ]
> @@ -230,7 +350,29 @@ static int prm_probe(gpr_device_t *gdev)
>  	if (!q6apm_is_adsp_ready())
>  		return -EPROBE_DEFER;
>  
> -	return devm_of_platform_populate(dev);
> +	ret = q6prm_clkctl_attach(cc);
> +	if (ret)
> +		return ret;
> +
> +	if (cc->clkctl)
> +		q6dsp_clock_dsp_up(&cc->clkctl->pdev->dev);
> +
> +	return 0;
> +}

[Severity: High]
Will q6dsp_clock_dsp_up() always time out when restoring lost clocks inside
prm_probe()?

apr_device_probe() only installs adrv->gpr_callback into adev->svc.callback
after adrv->probe() returns 0:

drivers/soc/qcom/apr.c:apr_device_probe() {
    ...
	ret = adrv->probe(adev);
	if (!ret)
		adev->svc.callback = adrv->gpr_callback;
    ...
}

When q6dsp_clock_dsp_up() sends PRM_CMD_REQUEST_HW_RSC via
q6prm_send_cmd_sync() -> audioreach_send_cmd_sync() and waits on prm->wait,
gdev->svc.callback is still NULL, so gpr_do_rx_callback() drops the DSP
response without calling prm_callback(). Every lost clock waits 5 seconds
and fails with -ETIMEDOUT, leaving clk->lost set. The same happens if a
consumer requests a clock after q6prm_clkctl_attach() sets ctl->prm and
calls of_platform_device_create() before prm_probe() returns.

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20261115032027.414953-1-shengchao.guo@oss.qualcomm.com?part=3