Re: [PATCH v4 7/8] slimbus: qcom-ngd-ctrl: Remove data channels on stream disable

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Low] slimbus: missing -EREMOTEIO check on RECONFIG_NOW in qcom_slim_ngd_disable_stream()
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commit 7a7223e63ca0ed5ba65c3227ee6a4afb69755791
Author: David Heidelberg <david@ixit.cz>
Subject: slimbus: qcom-ngd-ctrl: Remove data channels on stream disable

This patch implements the disable_stream controller operation for explicitly
removing data channels on stream disable. It sends a CHAN_CTRL(REMOVE)
message followed by RECONFIG_NOW to the ADSP SLIMbus master to prevent
channels from remaining active on closed streams.

> diff --git a/drivers/slimbus/qcom-ngd-ctrl.c b/drivers/slimbus/qcom-ngd-ctrl.c
> --- a/drivers/slimbus/qcom-ngd-ctrl.c
> +++ b/drivers/slimbus/qcom-ngd-ctrl.c

[ ... ]

> +static int qcom_slim_ngd_disable_stream(struct slim_stream_runtime *rt)
> +{

[ ... ]

> +	txn.mc = SLIM_USR_MC_CHAN_CTRL;
> +	txn.rl = txn.msg->num_bytes + 4;
> +	ret = qcom_slim_ngd_xfer_msg_sync(ctrl, &txn);
> +	if (ret) {
> +		slim_free_txn_tid(ctrl, &txn);
> +		/* Controller restarting, the channels are gone anyway */
> +		if (ret == -EREMOTEIO)
> +			return 0;
> +		dev_err(&sdev->dev, "TX timed out:MC:0x%x,mt:0x%x", txn.mc,
> +				txn.mt);
> +		return ret;
> +	}

[ ... ]

> +	ret = qcom_slim_ngd_xfer_msg_sync(ctrl, &txn);
> +	if (ret) {
> +		slim_free_txn_tid(ctrl, &txn);
> +		dev_err(&sdev->dev, "TX timed out:MC:0x%x,mt:0x%x", txn.mc,
> +				txn.mt);
> +	}
> +
> +	return ret;
> +}

[Severity: Low]
If the controller restarts during the SLIM_USR_MC_RECONFIG_NOW transfer,
qcom_slim_ngd_xfer_msg_sync() will return -EREMOTEIO. 

Does this second transfer intentionally omit the -EREMOTEIO check that is
present in the preceding SLIM_USR_MC_CHAN_CTRL transfer? 

Without the check, this path appears to log a spurious "TX timed out" error
when the controller restarts during teardown.

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Sashiko AI review · https://sashiko.dev/#/patchset/20260924-pixel3-audio-v4-0-85b5d133aa5e@ixit.cz?part=7