On Fri, 2 Jan 2026 at 13:07, Bartosz Golaszewski <[email protected]> wrote:
>
> On Wed, Dec 31, 2025 at 12:36 AM Dmitry Baryshkov
> <[email protected]> wrote:
> >
> > The WCN39xx family of WiFi/BT chips incorporates a simple PMU, spreading
> > voltages over internal rails. Implement support for using powersequencer
> > for this family of ATH10k devices in addition to using regulators.
> >
> > Signed-off-by: Dmitry Baryshkov <[email protected]>
> > ---
>
> [snip]
>
> >
> > static void ath10k_snoc_wlan_disable(struct ath10k *ar)
> > @@ -1762,7 +1779,27 @@ static int ath10k_snoc_probe(struct platform_device
> > *pdev)
> > goto err_release_resource;
> > }
> >
> > - ar_snoc->num_vregs = ARRAY_SIZE(ath10k_regulators);
> > + /*
> > + * Backwards compatibility, ignore the defer error from pwrseq, if
> > it
> > + * should be used, we will get an error from regulator get.
> > + */
>
> Can you elaborate on this? I'm not exactly following. I suppose you
> mean the regulator_get() will return -EPROBE_DEFER? One of the
> supplies exposed by the PMU?
Yes. devm_pwrseq_get() can return -EPROBE_DEFER in two cases:
- it is not supposed to be used
- it is supposed to be used, but the driver hasn't probed yet.
There is no simple way to distinguish between these two cases, but:
- if it is not supposed to be used, then regulator_bulk_get() will
return all regulators as expected, continuing the probe
- if it is supposed to be used, but wasn't probed yet, we will get
-EPROBE_DEFER from regulator_bulk_get() too.
I can write that in a comment, if you think that it makes the code more obvious.
>
> Bart
>
> > + ar_snoc->pwrseq = devm_pwrseq_get(&pdev->dev, "wlan");
> > + if (IS_ERR(ar_snoc->pwrseq)) {
> > + ret = PTR_ERR(ar_snoc->pwrseq);
> > + ar_snoc->pwrseq = NULL;
> > + if (ret != -EPROBE_DEFER)
> > + goto err_free_irq;
> > +
> > + ar_snoc->num_vregs = ARRAY_SIZE(ath10k_regulators);
> > + } else {
> > + /*
> > + * The first regulator (vdd-0.8-cx-mx) is used to power on
> > part
> > + * of the SoC rather than the PMU on WCN399x, the rest are
> > + * handled via pwrseq.
> > + */
> > + ar_snoc->num_vregs = 1;
> > + }
> > +
--
With best wishes
Dmitry
