Re: [PATCH v24 08/12] mfd: psci-mfd: Add psci-reboot-mode child cell

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] The MFD probe function swallows errors from devm_mfd_add_devices() instead of propagating them to abort the probe.
--

--- Patch [8]: [PATCH v24 08/12] mfd: psci-mfd: Add psci-reboot-mode child cell ---
commit 88cfe078ed8299db3dd71fd877f29ff443d5037e
Author: Shivendra Pratap <[email protected]>

mfd: psci-mfd: Add psci-reboot-mode child cell
    
This commit exposes the PSCI reboot-mode node as a proper child cell using
a named_fwnode. It also registers the psci-cpuidle-domain cell first to
isolate it from reboot-mode failures.

> diff --git a/drivers/mfd/psci-mfd.c b/drivers/mfd/psci-mfd.c
> index 7affd6bb09dd8..7befc4fa86f5d 100644
> --- a/drivers/mfd/psci-mfd.c
> +++ b/drivers/mfd/psci-mfd.c

[ ... ]

> @@ -14,10 +14,35 @@ static const struct mfd_cell psci_cells[] = {
>  static int psci_mfd_probe(struct platform_device *pdev)
>  {
> -	return devm_mfd_add_devices(&pdev->dev, PLATFORM_DEVID_AUTO, psci_cells,
> +	int ret;
> +
> +	ret = devm_mfd_add_devices(&pdev->dev, PLATFORM_DEVID_AUTO, psci_cells,
>  				   ARRAY_SIZE(psci_cells), NULL, 0, NULL);
> +	if (ret)
> +		goto out;
> +
> +	ret = devm_mfd_add_devices(&pdev->dev, PLATFORM_DEVID_AUTO,
> +				   psci_reboot_mode_cell,
> +				   ARRAY_SIZE(psci_reboot_mode_cell),
> +				   NULL, 0, NULL);
> +	if (ret) {
> +		if (ret == -ENOMEM)
> +			goto out;
> +		dev_warn(&pdev->dev, "reboot-mode child cell failed to add: %d\n", ret);
> +		ret = 0;
> +	}

[Severity: Medium]
Should this propagate the error instead of returning 0?

According to the MFD subsystem guidelines, if a child device fails to
register during an MFD probe, the entire probe must fail and unwind
previously registered children. By setting ret = 0 here, the driver reports
success for the parent probe even if the reboot-mode child cell fails to
register. Does this leave the device in an incomplete state and violate the
requirement to propagate devm_mfd_add_devices() errors?

> +
> +out:
> +	return ret;
>  }

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260803-arm-psci-system_reset2-vendor-reboots-v24-0-889281373870@oss.qualcomm.com?part=8