PM: runtime: Document return values of suspend-related API functions

Document return values for device suspend and idle related API
functions.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Link: https://patch.msgid.link/20250616061212.2286741-2-sakari.ailus@linux.intel.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 138 insertions, 9 deletions

diff --git a/include/linux/pm_runtime.h b/include/linux/pm_runtime.h
index e7cb70fcc0af..9dd2e4031a27 100644
--- a/include/linux/pm_runtime.h
+++ b/include/linux/pm_runtime.h
@@ -337,6 +337,20 @@ static inline void pm_runtime_release_supplier(struct device_link *link) {}
  * Invoke the "idle check" callback of @dev and, depending on its return value,
  * set up autosuspend of @dev or suspend it (depending on whether or not
  * autosuspend has been enabled for it).
+ *
+ * Return:
+ * * 0: Success.
+ * * -EINVAL: Runtime PM error.
+ * * -EACCES: Runtime PM disabled.
+ * * -EAGAIN: Runtime PM usage_count non-zero, Runtime PM status change ongoing
+ *            or device not in %RPM_ACTIVE state.
+ * * -EBUSY: Runtime PM child_count non-zero.
+ * * -EPERM: Device PM QoS resume latency 0.
+ * * -EINPROGRESS: Suspend already in progress.
+ * * -ENOSYS: CONFIG_PM not enabled.
+ * * 1: Device already suspended.
+ * Other values and conditions for the above values are possible as returned by
+ * Runtime PM idle and suspend callbacks.
  */
 static inline int pm_runtime_idle(struct device *dev)
 {
@@ -346,6 +360,18 @@ static inline int pm_runtime_idle(struct device *dev)
 /**
  * pm_runtime_suspend - Suspend a device synchronously.
  * @dev: Target device.
+ *
+ * Return:
+ * * 0: Success.
+ * * -EINVAL: Runtime PM error.
+ * * -EACCES: Runtime PM disabled.
+ * * -EAGAIN: Runtime PM usage_count non-zero or Runtime PM status change ongoing.
+ * * -EBUSY: Runtime PM child_count non-zero.
+ * * -EPERM: Device PM QoS resume latency 0.
+ * * -ENOSYS: CONFIG_PM not enabled.
+ * * 1: Device already suspended.
+ * Other values and conditions for the above values are possible as returned by
+ * Runtime PM suspend callbacks.
  */
 static inline int pm_runtime_suspend(struct device *dev)
 {
@@ -358,6 +384,18 @@ static inline int pm_runtime_suspend(struct device *dev)
  *
  * Set up autosuspend of @dev or suspend it (depending on whether or not
  * autosuspend is enabled for it) without engaging its "idle check" callback.
+ *
+ * Return:
+ * * 0: Success.
+ * * -EINVAL: Runtime PM error.
+ * * -EACCES: Runtime PM disabled.
+ * * -EAGAIN: Runtime PM usage_count non-zero or Runtime PM status change ongoing.
+ * * -EBUSY: Runtime PM child_count non-zero.
+ * * -EPERM: Device PM QoS resume latency 0.
+ * * -ENOSYS: CONFIG_PM not enabled.
+ * * 1: Device already suspended.
+ * Other values and conditions for the above values are possible as returned by
+ * Runtime PM suspend callbacks.
  */
 static inline int pm_runtime_autosuspend(struct device *dev)
 {
@@ -379,6 +417,18 @@ static inline int pm_runtime_resume(struct device *dev)
  *
  * Queue up a work item to run an equivalent of pm_runtime_idle() for @dev
  * asynchronously.
+ *
+ * Return:
+ * * 0: Success.
+ * * -EINVAL: Runtime PM error.
+ * * -EACCES: Runtime PM disabled.
+ * * -EAGAIN: Runtime PM usage_count non-zero, Runtime PM status change ongoing
+ *            or device not in %RPM_ACTIVE state.
+ * * -EBUSY: Runtime PM child_count non-zero.
+ * * -EPERM: Device PM QoS resume latency 0.
+ * * -EINPROGRESS: Suspend already in progress.
+ * * -ENOSYS: CONFIG_PM not enabled.
+ * * 1: Device already suspended.
  */
 static inline int pm_request_idle(struct device *dev)
 {
@@ -400,6 +450,17 @@ static inline int pm_request_resume(struct device *dev)
  *
  * Queue up a work item to run an equivalent pm_runtime_autosuspend() for @dev
  * asynchronously.
+ *
+ * Return:
+ * * 0: Success.
+ * * -EINVAL: Runtime PM error.
+ * * -EACCES: Runtime PM disabled.
+ * * -EAGAIN: Runtime PM usage_count non-zero or Runtime PM status change ongoing.
+ * * -EBUSY: Runtime PM child_count non-zero.
+ * * -EPERM: Device PM QoS resume latency 0.
+ * * -EINPROGRESS: Suspend already in progress.
+ * * -ENOSYS: CONFIG_PM not enabled.
+ * * 1: Device already suspended.
  */
 static inline int pm_request_autosuspend(struct device *dev)
 {
@@ -464,6 +525,17 @@ static inline int pm_runtime_resume_and_get(struct device *dev)
  *
  * 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_idle().
+ *
+ * Return:
+ * * 0: Success.
+ * * -EINVAL: Runtime PM error.
+ * * -EACCES: Runtime PM disabled.
+ * * -EAGAIN: Runtime PM usage_count non-zero or Runtime PM status change ongoing.
+ * * -EBUSY: Runtime PM child_count non-zero.
+ * * -EPERM: Device PM QoS resume latency 0.
+ * * -EINPROGRESS: Suspend already in progress.
+ * * -ENOSYS: CONFIG_PM not enabled.
+ * * 1: Device already suspended.
  */
 static inline int pm_runtime_put(struct device *dev)
 {
@@ -478,6 +550,17 @@ DEFINE_FREE(pm_runtime_put, struct device *, if (_T) pm_runtime_put(_T))
  *
  * 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().
+ *
+ * Return:
+ * * 0: Success.
+ * * -EINVAL: Runtime PM error.
+ * * -EACCES: Runtime PM disabled.
+ * * -EAGAIN: Runtime PM usage_count non-zero or Runtime PM status change ongoing.
+ * * -EBUSY: Runtime PM child_count non-zero.
+ * * -EPERM: Device PM QoS resume latency 0.
+ * * -EINPROGRESS: Suspend already in progress.
+ * * -ENOSYS: CONFIG_PM not enabled.
+ * * 1: Device already suspended.
  */
 static inline int __pm_runtime_put_autosuspend(struct device *dev)
 {
@@ -490,6 +573,17 @@ static inline int __pm_runtime_put_autosuspend(struct device *dev)
  *
  * 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().
+ *
+ * Return:
+ * * 0: Success.
+ * * -EINVAL: Runtime PM error.
+ * * -EACCES: Runtime PM disabled.
+ * * -EAGAIN: Runtime PM usage_count non-zero or Runtime PM status change ongoing.
+ * * -EBUSY: Runtime PM child_count non-zero.
+ * * -EPERM: Device PM QoS resume latency 0.
+ * * -EINPROGRESS: Suspend already in progress.
+ * * -ENOSYS: CONFIG_PM not enabled.
+ * * 1: Device already suspended.
  */
 static inline int pm_runtime_put_autosuspend(struct device *dev)
 {
@@ -506,9 +600,20 @@ static inline int pm_runtime_put_autosuspend(struct device *dev)
  * return value, set up autosuspend of @dev or suspend it (depending on whether
  * or not autosuspend has been enabled for it).
  *
- * The possible return values of this function are the same as for
- * pm_runtime_idle() and the runtime PM usage counter of @dev remains
- * decremented in all cases, even if it returns an error code.
+ * The runtime PM usage counter of @dev remains decremented in all cases, even
+ * if it returns an error code.
+ *
+ * Return:
+ * * 0: Success.
+ * * -EINVAL: Runtime PM error.
+ * * -EACCES: Runtime PM disabled.
+ * * -EAGAIN: Runtime PM usage_count non-zero or Runtime PM status change ongoing.
+ * * -EBUSY: Runtime PM child_count non-zero.
+ * * -EPERM: Device PM QoS resume latency 0.
+ * * -ENOSYS: CONFIG_PM not enabled.
+ * * 1: Device already suspended.
+ * Other values and conditions for the above values are possible as returned by
+ * Runtime PM suspend callbacks.
  */
 static inline int pm_runtime_put_sync(struct device *dev)
 {
@@ -522,9 +627,21 @@ static inline int pm_runtime_put_sync(struct device *dev)
  * Decrement the runtime PM usage counter of @dev and if it turns out to be
  * equal to 0, carry out runtime-suspend of @dev synchronously.
  *
- * The possible return values of this function are the same as for
- * pm_runtime_suspend() and the runtime PM usage counter of @dev remains
- * decremented in all cases, even if it returns an error code.
+ * The runtime PM usage counter of @dev remains decremented in all cases, even
+ * if it returns an error code.
+ *
+ * Return:
+ * * 0: Success.
+ * * -EINVAL: Runtime PM error.
+ * * -EACCES: Runtime PM disabled.
+ * * -EAGAIN: Runtime PM usage_count non-zero or Runtime PM status change ongoing.
+ * * -EAGAIN: usage_count non-zero or Runtime PM status change ongoing.
+ * * -EBUSY: Runtime PM child_count non-zero.
+ * * -EPERM: Device PM QoS resume latency 0.
+ * * -ENOSYS: CONFIG_PM not enabled.
+ * * 1: Device already suspended.
+ * Other values and conditions for the above values are possible as returned by
+ * Runtime PM suspend callbacks.
  */
 static inline int pm_runtime_put_sync_suspend(struct device *dev)
 {
@@ -539,9 +656,21 @@ static inline int pm_runtime_put_sync_suspend(struct device *dev)
  * equal to 0, set up autosuspend of @dev or suspend it synchronously (depending
  * on whether or not autosuspend has been enabled for it).
  *
- * The possible return values of this function are the same as for
- * pm_runtime_autosuspend() and the runtime PM usage counter of @dev remains
- * decremented in all cases, even if it returns an error code.
+ * The runtime PM usage counter of @dev remains decremented in all cases, even
+ * if it returns an error code.
+ *
+ * Return:
+ * * 0: Success.
+ * * -EINVAL: Runtime PM error.
+ * * -EACCES: Runtime PM disabled.
+ * * -EAGAIN: Runtime PM usage_count non-zero or Runtime PM status change ongoing.
+ * * -EBUSY: Runtime PM child_count non-zero.
+ * * -EPERM: Device PM QoS resume latency 0.
+ * * -EINPROGRESS: Suspend already in progress.
+ * * -ENOSYS: CONFIG_PM not enabled.
+ * * 1: Device already suspended.
+ * Other values and conditions for the above values are possible as returned by
+ * Runtime PM suspend callbacks.
  */
 static inline int pm_runtime_put_sync_autosuspend(struct device *dev)
 {