On Fri, 2 Jan 2026 at 13:07, Bartosz Golaszewski [off-list ref] wrote:

On Wed, Dec 31, 2025 at 12:36 AM Dmitry Baryshkov
[off-list ref] wrote:

quoted

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 <redacted>
---

[snip]

quoted

 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

quoted

+       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