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

[Shivendra Pratap]

On 8/12/2026 1:48 PM, Lee Jones wrote:
> On Mon, 03 Aug 2026, Shivendra Pratap wrote:
>
> > The PSCI "reboot-mode" node does not define a compatible because it is a
> > configuration of boot-states provided by the underlying firmware. With
> > the new firmware-node based cells in mfd-core, this node can now be
> > exposed as a proper child cell.
> >
> > Add the psci-reboot-mode child cell to the psci-mfd driver with a
> > named_fwnode. Add psci-cpuidle-domain cell first to isolate it from
> > reboot-mode failures.
> >
> > Suggested-by: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxxxxxxxx>
> > Signed-off-by: Shivendra Pratap <shivendra.pratap@xxxxxxxxxxxxxxxx>
> > ---
> >   drivers/mfd/psci-mfd.c      | 27 ++++++++++++++++++++++++++-
> >   drivers/power/reset/Kconfig |  2 +-
> >   2 files changed, 27 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/mfd/psci-mfd.c b/drivers/mfd/psci-mfd.c
> > index 7affd6bb09dd..7befc4fa86f5 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 const struct mfd_cell psci_reboot_mode_cell[] = {
> > +	{
> > +		.name = "psci-reboot-mode",
> > +		.named_fwnode = "reboot-mode",
> > +	},
> > +};
> > +
> >   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);
>
> Okay Yoda, but why is this okay?
>
> Needs a comment.

sure. Will add a comment in code.

psci-mfd adds two child cells, psci-cpuidle-domain and psci-reboot-mode.
psci-cpuidle-domain is boot-critical on supported systems.
psci-reboot-mode is added separately as an optional child. For 
non-critical failures from psci_reboot_mode_cell, we want to continue 
the probe of psci-mfd.

thanks,
Shivendra