@@ -1,6 +1,5 @@
-obj-$(CONFIG_PM) += sysfs.o generic_ops.o common.o qos.o
+obj-$(CONFIG_PM) += sysfs.o generic_ops.o common.o qos.o runtime.o
obj-$(CONFIG_PM_SLEEP) += main.o wakeup.o
-obj-$(CONFIG_PM_RUNTIME) += runtime.o
obj-$(CONFIG_PM_TRACE_RTC) += trace.o
obj-$(CONFIG_PM_OPP) += opp.o
obj-$(CONFIG_PM_GENERIC_DOMAINS) += domain.o domain_governor.o
@@ -13,6 +13,7 @@
#include <trace/events/rpm.h>
#include "power.h"
+#ifdef CONFIG_PM_RUNTIME
static int rpm_resume(struct device *dev, int rpmflags);
static int rpm_suspend(struct device *dev, int rpmflags);
@@ -1401,3 +1402,112 @@ void pm_runtime_remove(struct device *dev)
if (dev->power.irq_safe && dev->parent)
pm_runtime_put(dev->parent);
}
+#endif
+
+#ifdef CONFIG_PM
+/**
+ * pm_runtime_force_suspend - Force a device into suspend state if needed.
+ * @dev: Device to suspend.
+ *
+ * Disable runtime PM so we safely can check the device's runtime PM status and
+ * if it is active, invoke it's .runtime_suspend callback to bring it into
+ * suspend state. Keep runtime PM disabled to preserve the state unless we
+ * encounter errors.
+ *
+ * Typically this function may be invoked from a system suspend callback to make
+ * sure the device is put into low power state.
+ */
+int pm_runtime_force_suspend(struct device *dev)
+{
+ int (*callback)(struct device *);
+ int ret = 0;
+
+ pm_runtime_disable(dev);
+
+ /*
+ * Note that pm_runtime_status_suspended() returns false while
+ * !CONFIG_PM_RUNTIME, which means the device will be put into low
+ * power state.
+ */
+ if (pm_runtime_status_suspended(dev))
+ return 0;
+
+ if (dev->pm_domain)
+ callback = dev->pm_domain->ops.runtime_suspend;
+ else if (dev->type && dev->type->pm)
+ callback = dev->type->pm->runtime_suspend;
+ else if (dev->class && dev->class->pm)
+ callback = dev->class->pm->runtime_suspend;
+ else if (dev->bus && dev->bus->pm)
+ callback = dev->bus->pm->runtime_suspend;
+ else
+ callback = NULL;
+
+ if (!callback && dev->driver && dev->driver->pm)
+ callback = dev->driver->pm->runtime_suspend;
+
+ if (!callback) {
+ ret = -ENOSYS;
+ goto err;
+ }
+
+ ret = callback(dev);
+ if (ret)
+ goto err;
+
+ pm_runtime_set_suspended(dev);
+ return 0;
+err:
+ pm_runtime_enable(dev);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(pm_runtime_force_suspend);
+
+/**
+ * pm_runtime_force_resume - Force a device into resume state.
+ * @dev: Device to resume.
+ *
+ * Prior invoking this function we expect the user to have brought the device
+ * into low power state by a call to pm_runtime_force_suspend(). Here we reverse
+ * those actions and brings the device into full power. We update the runtime PM
+ * status and re-enables runtime PM.
+ *
+ * Typically this function may be invoked from a system resume callback to make
+ * sure the device is put into full power state.
+ */
+int pm_runtime_force_resume(struct device *dev)
+{
+ int (*callback)(struct device *);
+ int ret = 0;
+
+ if (dev->pm_domain)
+ callback = dev->pm_domain->ops.runtime_resume;
+ else if (dev->type && dev->type->pm)
+ callback = dev->type->pm->runtime_resume;
+ else if (dev->class && dev->class->pm)
+ callback = dev->class->pm->runtime_resume;
+ else if (dev->bus && dev->bus->pm)
+ callback = dev->bus->pm->runtime_resume;
+ else
+ callback = NULL;
+
+ if (!callback && dev->driver && dev->driver->pm)
+ callback = dev->driver->pm->runtime_resume;
+
+ if (!callback) {
+ ret = -ENOSYS;
+ goto out;
+ }
+
+ ret = callback(dev);
+ if (ret)
+ goto out;
+
+ pm_runtime_set_active(dev);
+ pm_runtime_mark_last_busy(dev);
+out:
+ pm_runtime_enable(dev);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(pm_runtime_force_resume);
+#endif
@@ -26,9 +26,13 @@
#ifdef CONFIG_PM
extern int pm_generic_runtime_suspend(struct device *dev);
extern int pm_generic_runtime_resume(struct device *dev);
+extern int pm_runtime_force_suspend(struct device *dev);
+extern int pm_runtime_force_resume(struct device *dev);
#else
static inline int pm_generic_runtime_suspend(struct device *dev) { return 0; }
static inline int pm_generic_runtime_resume(struct device *dev) { return 0; }
+static inline int pm_runtime_force_suspend(struct device *dev) { return 0; }
+static inline int pm_runtime_force_resume(struct device *dev) { return 0; }
#endif
#ifdef CONFIG_PM_RUNTIME
This patch provides two new runtime PM helper functions which intend to be used from system suspend/resume callbacks, to make sure devices are put into low power state during system suspend and brought back to full power at system resume. The prerequisite is to have all levels of a device's runtime PM callbacks to be defined through the SET_PM_RUNTIME_PM_OPS macro, which means these are available for CONFIG_PM. By using the new runtime PM helper functions especially the two scenarios below will be addressed. 1) The PM core prevents .runtime_suspend callbacks from being invoked during system suspend. That means even for a runtime PM centric subsystem and driver, the device needs to be put into low power state from a system suspend callback. Otherwise it may very well be left in full power state (runtime resumed) while the system is suspended. By using the new helper functions, we make sure to walk the hierarchy of a device's power domain, subsystem and driver. 2) Subsystems and drivers need to cope with all the combinations of CONFIG_PM_SLEEP and CONFIG_PM_RUNTIME. The two new helper functions smothly addresses this. Cc: Kevin Hilman <khilman@linaro.org> Cc: Alan Stern <stern@rowland.harvard.edu> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Mark Brown <broonie@linaro.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> --- Some relevant background to this patch: Recent discussions on linux-pm mailing list regarding a similar patch, but which added similar functionality as pm_generic* functions, which concluded to be dropped. http://marc.info/?t=138556666500004&r=1&w=2 Responses on recent sent patches, which are rejected from subsystem maintainers, while trying to adopt suspend/resume callbacks when using SET_PM_RUNTIME_PM_OPS. http://marc.info/?t=139152977000004&r=1&w=2 http://marc.info/?t=139152958400001&r=1&w=2 --- drivers/base/power/Makefile | 3 +- drivers/base/power/runtime.c | 110 ++++++++++++++++++++++++++++++++++++++++++ include/linux/pm_runtime.h | 4 ++ 3 files changed, 115 insertions(+), 2 deletions(-)