summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--Documentation/power/pci.txt14
-rw-r--r--drivers/base/power/main.c6
-rw-r--r--drivers/pci/pci-driver.c103
-rw-r--r--include/linux/pm.h2
4 files changed, 108 insertions, 17 deletions
diff --git a/Documentation/power/pci.txt b/Documentation/power/pci.txt
index ab4e7d0540c1..304162ea377e 100644
--- a/Documentation/power/pci.txt
+++ b/Documentation/power/pci.txt
@@ -980,6 +980,20 @@ positive value from pci_pm_prepare() if the ->prepare callback provided by the
driver of the device returns a positive value. That allows the driver to opt
out from using the direct-complete mechanism dynamically.
+The DPM_FLAG_SMART_SUSPEND flag tells the PCI bus type that from the driver's
+perspective the device can be safely left in runtime suspend during system
+suspend. That causes pci_pm_suspend(), pci_pm_freeze() and pci_pm_poweroff()
+to skip resuming the device from runtime suspend unless there are PCI-specific
+reasons for doing that. Also, it causes pci_pm_suspend_late/noirq(),
+pci_pm_freeze_late/noirq() and pci_pm_poweroff_late/noirq() to return early
+if the device remains in runtime suspend in the beginning of the "late" phase
+of the system-wide transition under way. Moreover, if the device is in
+runtime suspend in pci_pm_resume_noirq() or pci_pm_restore_noirq(), its runtime
+power management status will be changed to "active" (as it is going to be put
+into D0 going forward), but if it is in runtime suspend in pci_pm_thaw_noirq(),
+the function will set the power.direct_complete flag for it (to make the PM core
+skip the subsequent "thaw" callbacks for it) and return.
+
3.2. Device Runtime Power Management
------------------------------------
In addition to providing device power management callbacks PCI device drivers
diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c
index 8d9024017645..6c6f1c74c24c 100644
--- a/drivers/base/power/main.c
+++ b/drivers/base/power/main.c
@@ -1861,3 +1861,9 @@ void device_pm_check_callbacks(struct device *dev)
!dev->driver->suspend && !dev->driver->resume));
spin_unlock_irq(&dev->power.lock);
}
+
+bool dev_pm_smart_suspend_and_suspended(struct device *dev)
+{
+ return dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) &&
+ pm_runtime_status_suspended(dev);
+}
diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c
index c1aeeb10539e..d19bd54d337e 100644
--- a/drivers/pci/pci-driver.c
+++ b/drivers/pci/pci-driver.c
@@ -734,18 +734,25 @@ static int pci_pm_suspend(struct device *dev)
if (!pm) {
pci_pm_default_suspend(pci_dev);
- goto Fixup;
+ return 0;
}
/*
- * PCI devices suspended at run time need to be resumed at this point,
- * because in general it is necessary to reconfigure them for system
- * suspend. Namely, if the device is supposed to wake up the system
- * from the sleep state, we may need to reconfigure it for this purpose.
- * In turn, if the device is not supposed to wake up the system from the
- * sleep state, we'll have to prevent it from signaling wake-up.
+ * PCI devices suspended at run time may need to be resumed at this
+ * point, because in general it may be necessary to reconfigure them for
+ * system suspend. Namely, if the device is expected to wake up the
+ * system from the sleep state, it may have to be reconfigured for this
+ * purpose, or if the device is not expected to wake up the system from
+ * the sleep state, it should be prevented from signaling wakeup events
+ * going forward.
+ *
+ * Also if the driver of the device does not indicate that its system
+ * suspend callbacks can cope with runtime-suspended devices, it is
+ * better to resume the device from runtime suspend here.
*/
- pm_runtime_resume(dev);
+ if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) ||
+ !pci_dev_keep_suspended(pci_dev))
+ pm_runtime_resume(dev);
pci_dev->state_saved = false;
if (pm->suspend) {
@@ -765,17 +772,27 @@ static int pci_pm_suspend(struct device *dev)
}
}
- Fixup:
- pci_fixup_device(pci_fixup_suspend, pci_dev);
-
return 0;
}
+static int pci_pm_suspend_late(struct device *dev)
+{
+ if (dev_pm_smart_suspend_and_suspended(dev))
+ return 0;
+
+ pci_fixup_device(pci_fixup_suspend, to_pci_dev(dev));
+
+ return pm_generic_suspend_late(dev);
+}
+
static int pci_pm_suspend_noirq(struct device *dev)
{
struct pci_dev *pci_dev = to_pci_dev(dev);
const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
+ if (dev_pm_smart_suspend_and_suspended(dev))
+ return 0;
+
if (pci_has_legacy_pm_support(pci_dev))
return pci_legacy_suspend_late(dev, PMSG_SUSPEND);
@@ -834,6 +851,14 @@ static int pci_pm_resume_noirq(struct device *dev)
struct device_driver *drv = dev->driver;
int error = 0;
+ /*
+ * Devices with DPM_FLAG_SMART_SUSPEND may be left in runtime suspend
+ * during system suspend, so update their runtime PM status to "active"
+ * as they are going to be put into D0 shortly.
+ */
+ if (dev_pm_smart_suspend_and_suspended(dev))
+ pm_runtime_set_active(dev);
+
pci_pm_default_resume_early(pci_dev);
if (pci_has_legacy_pm_support(pci_dev))
@@ -876,6 +901,7 @@ static int pci_pm_resume(struct device *dev)
#else /* !CONFIG_SUSPEND */
#define pci_pm_suspend NULL
+#define pci_pm_suspend_late NULL
#define pci_pm_suspend_noirq NULL
#define pci_pm_resume NULL
#define pci_pm_resume_noirq NULL
@@ -910,7 +936,8 @@ static int pci_pm_freeze(struct device *dev)
* devices should not be touched during freeze/thaw transitions,
* however.
*/
- pm_runtime_resume(dev);
+ if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND))
+ pm_runtime_resume(dev);
pci_dev->state_saved = false;
if (pm->freeze) {
@@ -925,11 +952,22 @@ static int pci_pm_freeze(struct device *dev)
return 0;
}
+static int pci_pm_freeze_late(struct device *dev)
+{
+ if (dev_pm_smart_suspend_and_suspended(dev))
+ return 0;
+
+ return pm_generic_freeze_late(dev);;
+}
+
static int pci_pm_freeze_noirq(struct device *dev)
{
struct pci_dev *pci_dev = to_pci_dev(dev);
struct device_driver *drv = dev->driver;
+ if (dev_pm_smart_suspend_and_suspended(dev))
+ return 0;
+
if (pci_has_legacy_pm_support(pci_dev))
return pci_legacy_suspend_late(dev, PMSG_FREEZE);
@@ -959,6 +997,16 @@ static int pci_pm_thaw_noirq(struct device *dev)
struct device_driver *drv = dev->driver;
int error = 0;
+ /*
+ * If the device is in runtime suspend, the code below may not work
+ * correctly with it, so skip that code and make the PM core skip all of
+ * the subsequent "thaw" callbacks for the device.
+ */
+ if (dev_pm_smart_suspend_and_suspended(dev)) {
+ dev->power.direct_complete = true;
+ return 0;
+ }
+
if (pcibios_pm_ops.thaw_noirq) {
error = pcibios_pm_ops.thaw_noirq(dev);
if (error)
@@ -1008,11 +1056,13 @@ static int pci_pm_poweroff(struct device *dev)
if (!pm) {
pci_pm_default_suspend(pci_dev);
- goto Fixup;
+ return 0;
}
/* The reason to do that is the same as in pci_pm_suspend(). */
- pm_runtime_resume(dev);
+ if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) ||
+ !pci_dev_keep_suspended(pci_dev))
+ pm_runtime_resume(dev);
pci_dev->state_saved = false;
if (pm->poweroff) {
@@ -1024,17 +1074,27 @@ static int pci_pm_poweroff(struct device *dev)
return error;
}
- Fixup:
- pci_fixup_device(pci_fixup_suspend, pci_dev);
-
return 0;
}
+static int pci_pm_poweroff_late(struct device *dev)
+{
+ if (dev_pm_smart_suspend_and_suspended(dev))
+ return 0;
+
+ pci_fixup_device(pci_fixup_suspend, to_pci_dev(dev));
+
+ return pm_generic_poweroff_late(dev);
+}
+
static int pci_pm_poweroff_noirq(struct device *dev)
{
struct pci_dev *pci_dev = to_pci_dev(dev);
struct device_driver *drv = dev->driver;
+ if (dev_pm_smart_suspend_and_suspended(dev))
+ return 0;
+
if (pci_has_legacy_pm_support(to_pci_dev(dev)))
return pci_legacy_suspend_late(dev, PMSG_HIBERNATE);
@@ -1076,6 +1136,10 @@ static int pci_pm_restore_noirq(struct device *dev)
struct device_driver *drv = dev->driver;
int error = 0;
+ /* This is analogous to the pci_pm_resume_noirq() case. */
+ if (dev_pm_smart_suspend_and_suspended(dev))
+ pm_runtime_set_active(dev);
+
if (pcibios_pm_ops.restore_noirq) {
error = pcibios_pm_ops.restore_noirq(dev);
if (error)
@@ -1124,10 +1188,12 @@ static int pci_pm_restore(struct device *dev)
#else /* !CONFIG_HIBERNATE_CALLBACKS */
#define pci_pm_freeze NULL
+#define pci_pm_freeze_late NULL
#define pci_pm_freeze_noirq NULL
#define pci_pm_thaw NULL
#define pci_pm_thaw_noirq NULL
#define pci_pm_poweroff NULL
+#define pci_pm_poweroff_late NULL
#define pci_pm_poweroff_noirq NULL
#define pci_pm_restore NULL
#define pci_pm_restore_noirq NULL
@@ -1243,10 +1309,13 @@ static const struct dev_pm_ops pci_dev_pm_ops = {
.prepare = pci_pm_prepare,
.complete = pci_pm_complete,
.suspend = pci_pm_suspend,
+ .suspend_late = pci_pm_suspend_late,
.resume = pci_pm_resume,
.freeze = pci_pm_freeze,
+ .freeze_late = pci_pm_freeze_late,
.thaw = pci_pm_thaw,
.poweroff = pci_pm_poweroff,
+ .poweroff_late = pci_pm_poweroff_late,
.restore = pci_pm_restore,
.suspend_noirq = pci_pm_suspend_noirq,
.resume_noirq = pci_pm_resume_noirq,
diff --git a/include/linux/pm.h b/include/linux/pm.h
index 43b5418e05bb..65d39115f06d 100644
--- a/include/linux/pm.h
+++ b/include/linux/pm.h
@@ -765,6 +765,8 @@ extern int pm_generic_poweroff_late(struct device *dev);
extern int pm_generic_poweroff(struct device *dev);
extern void pm_generic_complete(struct device *dev);
+extern bool dev_pm_smart_suspend_and_suspended(struct device *dev);
+
#else /* !CONFIG_PM_SLEEP */
#define device_pm_lock() do {} while (0)