Merge branch 'pm-runtime'

Merge changes related to the runtime power management of devices for
6.9-rc1:

 - Simplify pm_runtime_get_if_active() usage and add a replacement for
   pm_runtime_put_autosuspend() (Sakari Ailus).

 - Add a tracepoint for runtime_status changes tracking (Vilas Bhat).

 - Fix section title markdown in the runtime PM documentation (Yiwei
   Lin).

* pm-runtime:
  Documentation: PM: Fix runtime_pm.rst markdown syntax
  PM: runtime: add tracepoint for runtime_status changes
  PM: runtime: Add pm_runtime_put_autosuspend() replacement
  PM: runtime: Simplify pm_runtime_get_if_active() usage

Documentation/power/runtime_pm.rst

@@ -154,7 +154,7 @@ suspending the device are satisfied) and to queue up a suspend request for the
 device in that case.  If there is no idle callback, or if the callback returns
 0, then the PM core will attempt to carry out a runtime suspend of the device,
 also respecting devices configured for autosuspend.  In essence this means a
-call to pm_runtime_autosuspend() (do note that drivers needs to update the
+call to __pm_runtime_autosuspend() (do note that drivers needs to update the
 device last busy mark, pm_runtime_mark_last_busy(), to control the delay under
 this circumstance).  To prevent this (for example, if the callback routine has
 started a delayed suspend), the routine must return a non-zero value.  Negative
@@ -396,10 +396,9 @@ drivers/base/power/runtime.c and include/linux/pm_runtime.h:
       nonzero, increment the counter and return 1; otherwise return 0 without
       changing the counter
 
-  `int pm_runtime_get_if_active(struct device *dev, bool ign_usage_count);`
+  `int pm_runtime_get_if_active(struct device *dev);`
     - return -EINVAL if 'power.disable_depth' is nonzero; otherwise, if the
-      runtime PM status is RPM_ACTIVE, and either ign_usage_count is true
-      or the device's usage_count is non-zero, increment the counter and
+      runtime PM status is RPM_ACTIVE, increment the counter and
       return 1; otherwise return 0 without changing the counter
 
   `void pm_runtime_put_noidle(struct device *dev);`
@@ -410,6 +409,10 @@ drivers/base/power/runtime.c and include/linux/pm_runtime.h:
       pm_request_idle(dev) and return its result
 
   `int pm_runtime_put_autosuspend(struct device *dev);`
+    - does the same as __pm_runtime_put_autosuspend() for now, but in the
+      future, will also call pm_runtime_mark_last_busy() as well, DO NOT USE!
+
+  `int __pm_runtime_put_autosuspend(struct device *dev);`
     - decrement the device's usage counter; if the result is 0 then run
       pm_request_autosuspend(dev) and return its result
 
@@ -540,6 +543,7 @@ It is safe to execute the following helper functions from interrupt context:
 - pm_runtime_put_noidle()
 - pm_runtime_put()
 - pm_runtime_put_autosuspend()
+- __pm_runtime_put_autosuspend()
 - pm_runtime_enable()
 - pm_suspend_ignore_children()
 - pm_runtime_set_active()
@@ -730,6 +734,7 @@ out the following operations:
     for it, respectively.
 
 7. Generic subsystem callbacks
+==============================
 
 Subsystems may wish to conserve code space by using the set of generic power
 management callbacks provided by the PM core, defined in
@@ -865,9 +870,9 @@ automatically be delayed until the desired period of inactivity has elapsed.
 
 Inactivity is determined based on the power.last_busy field.  Drivers should
 call pm_runtime_mark_last_busy() to update this field after carrying out I/O,
-typically just before calling pm_runtime_put_autosuspend().  The desired length
-of the inactivity period is a matter of policy.  Subsystems can set this length
-initially by calling pm_runtime_set_autosuspend_delay(), but after device
+typically just before calling __pm_runtime_put_autosuspend().  The desired
+length of the inactivity period is a matter of policy.  Subsystems can set this
+length initially by calling pm_runtime_set_autosuspend_delay(), but after device
 registration the length should be controlled by user space, using the
 /sys/devices/.../power/autosuspend_delay_ms attribute.
 
@@ -878,7 +883,7 @@ instead of the non-autosuspend counterparts::
 
 	Instead of: pm_runtime_suspend    use: pm_runtime_autosuspend;
 	Instead of: pm_schedule_suspend   use: pm_request_autosuspend;
-	Instead of: pm_runtime_put        use: pm_runtime_put_autosuspend;
+	Instead of: pm_runtime_put        use: __pm_runtime_put_autosuspend;
 	Instead of: pm_runtime_put_sync   use: pm_runtime_put_sync_autosuspend.
 
 Drivers may also continue to use the non-autosuspend helper functions; they
@@ -917,7 +922,7 @@ Here is a schematic pseudo-code example::
 		lock(&foo->private_lock);
 		if (--foo->num_pending_requests == 0) {
 			pm_runtime_mark_last_busy(&foo->dev);
-			pm_runtime_put_autosuspend(&foo->dev);
+			__pm_runtime_put_autosuspend(&foo->dev);
 		} else {
 			foo_process_next_request(foo);
 		}

drivers/accel/ivpu/ivpu_pm.c

@@ -309,7 +309,7 @@ int ivpu_rpm_get_if_active(struct ivpu_device *vdev)
 {
 	int ret;
 
-	ret = pm_runtime_get_if_active(vdev->drm.dev, false);
+	ret = pm_runtime_get_if_in_use(vdev->drm.dev);
 	drm_WARN_ON(&vdev->drm, ret < 0);
 
 	return ret;

drivers/base/power/runtime.c

@@ -94,6 +94,7 @@ static void update_pm_runtime_accounting(struct device *dev)
 static void __update_runtime_status(struct device *dev, enum rpm_status status)
 {
 	update_pm_runtime_accounting(dev);
+	trace_rpm_status(dev, status);
 	dev->power.runtime_status = status;
 }
 
@@ -1176,7 +1177,7 @@ int __pm_runtime_resume(struct device *dev, int rpmflags)
 EXPORT_SYMBOL_GPL(__pm_runtime_resume);
 
 /**
- * pm_runtime_get_if_active - Conditionally bump up device usage counter.
+ * pm_runtime_get_conditional - Conditionally bump up device usage counter.
  * @dev: Device to handle.
  * @ign_usage_count: Whether or not to look at the current usage counter value.
  *
@@ -1197,7 +1198,7 @@ EXPORT_SYMBOL_GPL(__pm_runtime_resume);
  * The caller is responsible for decrementing the runtime PM usage counter of
  * @dev after this function has returned a positive value for it.
  */
-int pm_runtime_get_if_active(struct device *dev, bool ign_usage_count)
+static int pm_runtime_get_conditional(struct device *dev, bool ign_usage_count)
 {
 	unsigned long flags;
 	int retval;
@@ -1218,8 +1219,39 @@ int pm_runtime_get_if_active(struct device *dev, bool ign_usage_count)
 
 	return retval;
 }
+
+/**
+ * pm_runtime_get_if_active - Bump up runtime PM usage counter if the device is
+ *			      in active state
+ * @dev: Target device.
+ *
+ * Increment the runtime PM usage counter of @dev if its runtime PM status is
+ * %RPM_ACTIVE, in which case it returns 1. If the device is in a different
+ * state, 0 is returned. -EINVAL is returned if runtime PM is disabled for the
+ * device, in which case also the usage_count will remain unmodified.
+ */
+int pm_runtime_get_if_active(struct device *dev)
+{
+	return pm_runtime_get_conditional(dev, true);
+}
 EXPORT_SYMBOL_GPL(pm_runtime_get_if_active);
 
+/**
+ * pm_runtime_get_if_in_use - Conditionally bump up runtime PM usage counter.
+ * @dev: Target device.
+ *
+ * Increment the runtime PM usage counter of @dev if its runtime PM status is
+ * %RPM_ACTIVE and its runtime PM usage counter is greater than 0, in which case
+ * it returns 1. If the device is in a different state or its usage_count is 0,
+ * 0 is returned. -EINVAL is returned if runtime PM is disabled for the device,
+ * in which case also the usage_count will remain unmodified.
+ */
+int pm_runtime_get_if_in_use(struct device *dev)
+{
+	return pm_runtime_get_conditional(dev, false);
+}
+EXPORT_SYMBOL_GPL(pm_runtime_get_if_in_use);
+
 /**
  * __pm_runtime_set_status - Set runtime PM status of a device.
  * @dev: Device to handle.

drivers/gpu/drm/i915/intel_runtime_pm.c

@@ -246,7 +246,10 @@ static intel_wakeref_t __intel_runtime_pm_get_if_active(struct intel_runtime_pm
 		 * function, since the power state is undefined. This applies
 		 * atm to the late/early system suspend/resume handlers.
 		 */
-		if (pm_runtime_get_if_active(rpm->kdev, ignore_usecount) <= 0)
+		if ((ignore_usecount &&
+		     pm_runtime_get_if_active(rpm->kdev) <= 0) ||
+		    (!ignore_usecount &&
+		     pm_runtime_get_if_in_use(rpm->kdev) <= 0))
 			return 0;
 	}
 

drivers/gpu/drm/xe/xe_pm.c

@@ -330,7 +330,7 @@ int xe_pm_runtime_put(struct xe_device *xe)
 
 int xe_pm_runtime_get_if_active(struct xe_device *xe)
 {
-	return pm_runtime_get_if_active(xe->drm.dev, true);
+	return pm_runtime_get_if_active(xe->drm.dev);
 }
 
 void xe_pm_assert_unbounded_bridge(struct xe_device *xe)

drivers/media/i2c/ccs/ccs-core.c

@@ -674,7 +674,7 @@ static int ccs_set_ctrl(struct v4l2_ctrl *ctrl)
 		break;
 	}
 
-	pm_status = pm_runtime_get_if_active(&client->dev, true);
+	pm_status = pm_runtime_get_if_active(&client->dev);
 	if (!pm_status)
 		return 0;
 

drivers/media/i2c/ov64a40.c

@@ -3287,7 +3287,7 @@ static int ov64a40_set_ctrl(struct v4l2_ctrl *ctrl)
 					 exp_max, 1, exp_val);
 	}
 
-	pm_status = pm_runtime_get_if_active(ov64a40->dev, true);
+	pm_status = pm_runtime_get_if_active(ov64a40->dev);
 	if (!pm_status)
 		return 0;
 

drivers/media/i2c/thp7312.c

@@ -1052,7 +1052,7 @@ static int thp7312_s_ctrl(struct v4l2_ctrl *ctrl)
 	if (ctrl->flags & V4L2_CTRL_FLAG_INACTIVE)
 		return -EINVAL;
 
-	if (!pm_runtime_get_if_active(thp7312->dev, true))
+	if (!pm_runtime_get_if_active(thp7312->dev))
 		return 0;
 
 	switch (ctrl->id) {

drivers/net/ipa/ipa_smp2p.c

@@ -92,7 +92,7 @@ static void ipa_smp2p_notify(struct ipa_smp2p *smp2p)
 		return;
 
 	dev = &smp2p->ipa->pdev->dev;
-	smp2p->power_on = pm_runtime_get_if_active(dev, true) > 0;
+	smp2p->power_on = pm_runtime_get_if_active(dev) > 0;
 
 	/* Signal whether the IPA power is enabled */
 	mask = BIT(smp2p->enabled_bit);

drivers/pci/pci.c

@@ -2532,7 +2532,7 @@ static void pci_pme_list_scan(struct work_struct *work)
 			 * course of the call.
 			 */
 			if (bdev) {
-				bref = pm_runtime_get_if_active(bdev, true);
+				bref = pm_runtime_get_if_active(bdev);
 				if (!bref)
 					continue;
 

include/linux/pm_runtime.h

@@ -72,7 +72,8 @@ extern int pm_runtime_force_resume(struct device *dev);
 extern int __pm_runtime_idle(struct device *dev, int rpmflags);
 extern int __pm_runtime_suspend(struct device *dev, int rpmflags);
 extern int __pm_runtime_resume(struct device *dev, int rpmflags);
-extern int pm_runtime_get_if_active(struct device *dev, bool ign_usage_count);
+extern int pm_runtime_get_if_active(struct device *dev);
+extern int pm_runtime_get_if_in_use(struct device *dev);
 extern int pm_schedule_suspend(struct device *dev, unsigned int delay);
 extern int __pm_runtime_set_status(struct device *dev, unsigned int status);
 extern int pm_runtime_barrier(struct device *dev);
@@ -94,18 +95,6 @@ extern void pm_runtime_release_supplier(struct device_link *link);
 
 extern int devm_pm_runtime_enable(struct device *dev);
 
-/**
- * pm_runtime_get_if_in_use - Conditionally bump up runtime PM usage counter.
- * @dev: Target device.
- *
- * Increment the runtime PM usage counter of @dev if its runtime PM status is
- * %RPM_ACTIVE and its runtime PM usage counter is greater than 0.
- */
-static inline int pm_runtime_get_if_in_use(struct device *dev)
-{
-	return pm_runtime_get_if_active(dev, false);
-}
-
 /**
  * pm_suspend_ignore_children - Set runtime PM behavior regarding children.
  * @dev: Target device.
@@ -275,8 +264,7 @@ static inline int pm_runtime_get_if_in_use(struct device *dev)
 {
 	return -EINVAL;
 }
-static inline int pm_runtime_get_if_active(struct device *dev,
-					   bool ign_usage_count)
+static inline int pm_runtime_get_if_active(struct device *dev)
 {
 	return -EINVAL;
 }
@@ -460,6 +448,18 @@ static inline int pm_runtime_put(struct device *dev)
 	return __pm_runtime_idle(dev, RPM_GET_PUT | RPM_ASYNC);
 }
 
+/**
+ * __pm_runtime_put_autosuspend - Drop device usage counter and queue autosuspend if 0.
+ * @dev: Target device.
+ *
+ * Decrement the runtime PM usage counter of @dev and if it turns out to be
+ * equal to 0, queue up a work item for @dev like in pm_request_autosuspend().
+ */
+static inline int __pm_runtime_put_autosuspend(struct device *dev)
+{
+	return __pm_runtime_suspend(dev, RPM_GET_PUT | RPM_ASYNC | RPM_AUTO);
+}
+
 /**
  * pm_runtime_put_autosuspend - Drop device usage counter and queue autosuspend if 0.
  * @dev: Target device.

include/trace/events/rpm.h

@@ -101,6 +101,48 @@ TRACE_EVENT(rpm_return_int,
 		__entry->ret)
 );
 
+#define RPM_STATUS_STRINGS \
+	EM(RPM_INVALID, "RPM_INVALID") \
+	EM(RPM_ACTIVE, "RPM_ACTIVE") \
+	EM(RPM_RESUMING, "RPM_RESUMING") \
+	EM(RPM_SUSPENDED, "RPM_SUSPENDED") \
+	EMe(RPM_SUSPENDING, "RPM_SUSPENDING")
+
+/* Enums require being exported to userspace, for user tool parsing. */
+#undef EM
+#undef EMe
+#define EM(a, b)	TRACE_DEFINE_ENUM(a);
+#define EMe(a, b)	TRACE_DEFINE_ENUM(a);
+
+RPM_STATUS_STRINGS
+
+/*
+ * Now redefine the EM() and EMe() macros to map the enums to the strings that
+ * will be printed in the output.
+ */
+#undef EM
+#undef EMe
+#define EM(a, b)	{ a, b },
+#define EMe(a, b)	{ a, b }
+
+TRACE_EVENT(rpm_status,
+	TP_PROTO(struct device *dev, enum rpm_status status),
+	TP_ARGS(dev, status),
+
+	TP_STRUCT__entry(
+		__string(name,	dev_name(dev))
+		__field(int,	status)
+	),
+
+	TP_fast_assign(
+		__assign_str(name, dev_name(dev));
+		__entry->status = status;
+	),
+
+	TP_printk("%s status=%s", __get_str(name),
+		__print_symbolic(__entry->status, RPM_STATUS_STRINGS))
+);
+
 #endif /* _TRACE_RUNTIME_POWER_H */
 
 /* This part must be outside protection */

sound/hda/hdac_device.c

@@ -612,7 +612,7 @@ EXPORT_SYMBOL_GPL(snd_hdac_power_up_pm);
 int snd_hdac_keep_power_up(struct hdac_device *codec)
 {
 	if (!atomic_inc_not_zero(&codec->in_pm)) {
-		int ret = pm_runtime_get_if_active(&codec->dev, true);
+		int ret = pm_runtime_get_if_active(&codec->dev);
 		if (!ret)
 			return -1;
 		if (ret < 0)