[PATCH v1 2/2] driver core/PM: Set power.no_callbacks along with power.no_pm

Rafael J. Wysocki
2025-08-28T10:59:46Z

From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Devices with power.no_pm set are not expected to need any power
management at all, so modify device_set_pm_not_required() to set
power.no_callbacks for them too in case runtime PM will be enabled
for any of them (which in principle may be done for convenience if
such a device participates in a dependency chain).

Since device_set_pm_not_required() must be called before device_add()
or it would not have any effect, it can update power.no_callbacks
without locking, unlike pm_runtime_no_callbacks() that can be called
after registering the target device.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
include/linux/device.h | 3 +++
1 file changed, 3 insertions(+)

--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -851,6 +851,9 @@
static inline void device_set_pm_not_required(struct device *dev)
{
dev->power.no_pm = true;
+#ifdef CONFIG_PM
+ dev->power.no_callbacks = true;
+#endif
}

static inline void dev_pm_syscore_device(struct device *dev, bool val)