Re:[PATCH 2/2] regulator: irq: freeze deferred hardware access during suspend

[jiale yao]

At 2026-10-16 18:05:22, "Jiale Yao" <yaojiale02@xxxxxxx> wrote:
>The regulator IRQ helper delays status checks and recovery callbacks on
>non-freezable workqueues. Those callbacks may access regulator hardware
>after the backing bus has been suspended.
>
>Use system_freezable_wq for normal-priority callbacks. Allocate a
>freezable high-priority workqueue when requested so the high_prio
>contract is preserved while hardware access is frozen across suspend.
>

Fixes: 7111c6d1b31b ("regulator: IRQ based event/error notification helpers")

>Signed-off-by: Jiale Yao <yaojiale02@xxxxxxx>
>---
> drivers/regulator/irq_helpers.c | 38 +++++++++++++++++++--------------
> 1 file changed, 22 insertions(+), 16 deletions(-)
>
>diff --git a/drivers/regulator/irq_helpers.c b/drivers/regulator/irq_helpers.c
>index 5b3cfac28667..cdbd170d2b15 100644
>--- a/drivers/regulator/irq_helpers.c
>+++ b/drivers/regulator/irq_helpers.c
>@@ -15,6 +15,7 @@
> #include <linux/regmap.h>
> #include <linux/slab.h>
> #include <linux/spinlock.h>
>+#include <linux/workqueue.h>
> #include <linux/regulator/driver.h>
> 
> #include "internal.h"
>@@ -27,6 +28,7 @@ struct regulator_irq {
> 	int irq;
> 	int retry_cnt;
> 	struct delayed_work isr_work;
>+	struct workqueue_struct *wq;
> };
> 
> /*
>@@ -145,12 +147,7 @@ static void regulator_notifier_isr_work(struct work_struct *work)
> 	return;
> 
> reschedule:
>-	if (!d->high_prio)
>-		mod_delayed_work(system_dfl_wq, &h->isr_work,
>-				 msecs_to_jiffies(tmo));
>-	else
>-		mod_delayed_work(system_highpri_wq, &h->isr_work,
>-				 msecs_to_jiffies(tmo));
>+	mod_delayed_work(h->wq, &h->isr_work, msecs_to_jiffies(tmo));
> }
> 
> static irqreturn_t regulator_notifier_isr(int irq, void *data)
>@@ -248,13 +245,8 @@ static irqreturn_t regulator_notifier_isr(int irq, void *data)
> 	}
> 
> 	if (d->irq_off_ms) {
>-		if (!d->high_prio)
>-			schedule_delayed_work(&h->isr_work,
>-					      msecs_to_jiffies(d->irq_off_ms));
>-		else
>-			mod_delayed_work(system_highpri_wq,
>-					 &h->isr_work,
>-					 msecs_to_jiffies(d->irq_off_ms));
>+		mod_delayed_work(h->wq, &h->isr_work,
>+				 msecs_to_jiffies(d->irq_off_ms));
> 	}
> 
> 	return IRQ_HANDLED;
>@@ -363,13 +355,25 @@ void *regulator_irq_helper(struct device *dev,
> 
> 	init_rdev_errors(h);
> 
>-	if (h->desc.irq_off_ms)
>+	if (h->desc.irq_off_ms) {
>+		if (h->desc.high_prio) {
>+			h->wq = alloc_workqueue("regulator_irq_highpri",
>+						WQ_FREEZABLE | WQ_HIGHPRI, 0);
>+			if (!h->wq)
>+				return ERR_PTR(-ENOMEM);
>+		} else {
>+			h->wq = system_freezable_wq;
>+		}
>+
> 		INIT_DELAYED_WORK(&h->isr_work, regulator_notifier_isr_work);
>+	}
> 
> 	ret = request_threaded_irq(h->irq, NULL, regulator_notifier_isr,
> 				   IRQF_ONESHOT | irq_flags, h->desc.name, h);
> 	if (ret) {
> 		dev_err(dev, "Failed to request IRQ %d\n", irq);
>+		if (h->desc.irq_off_ms && h->desc.high_prio)
>+			destroy_workqueue(h->wq);
> 
> 		return ERR_PTR(ret);
> 	}
>@@ -393,8 +397,11 @@ void regulator_irq_helper_cancel(void **handle)
> 		struct regulator_irq *h = *handle;
> 
> 		free_irq(h->irq, h);
>-		if (h->desc.irq_off_ms)
>+		if (h->desc.irq_off_ms) {
> 			cancel_delayed_work_sync(&h->isr_work);
>+			if (h->desc.high_prio)
>+				destroy_workqueue(h->wq);
>+		}
> 
> 		h = NULL;
> 	}
>@@ -441,4 +448,3 @@ int regulator_irq_map_event_simple(int irq, struct regulator_irq_data *rid,
> 	return 0;
> }
> EXPORT_SYMBOL_GPL(regulator_irq_map_event_simple);
>-
>-- 
>2.34.1