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authorLinus Torvalds <torvalds@linux-foundation.org>2011-06-23 06:08:52 +0200
committerLinus Torvalds <torvalds@linux-foundation.org>2011-06-23 06:08:52 +0200
commit68d0080f1e222757c85606d3eaf81b5c4aa7719f (patch)
tree5f177f7571a56e7dfe3888f67fcc86532be8235c
parentmm, hotplug: protect zonelist building with zonelists_mutex (diff)
parentPCI / PM: Block races between runtime PM and system sleep (diff)
downloadlinux-68d0080f1e222757c85606d3eaf81b5c4aa7719f.tar.xz
linux-68d0080f1e222757c85606d3eaf81b5c4aa7719f.zip
Merge branch 'pm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6
* 'pm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6: PCI / PM: Block races between runtime PM and system sleep PM / Domains: Update documentation PM / Runtime: Handle clocks correctly if CONFIG_PM_RUNTIME is unset PM: Fix async resume following suspend failure PM: Free memory bitmaps if opening /dev/snapshot fails PM: Rename dev_pm_info.in_suspend to is_prepared PM: Update documentation regarding sysdevs PM / Runtime: Update doc: usage count no longer incremented across system PM
-rw-r--r--Documentation/power/devices.txt67
-rw-r--r--Documentation/power/runtime_pm.txt5
-rw-r--r--drivers/base/power/clock_ops.c4
-rw-r--r--drivers/base/power/main.c28
-rw-r--r--drivers/pci/pci-driver.c4
-rw-r--r--drivers/usb/core/driver.c6
-rw-r--r--include/linux/device.h4
-rw-r--r--include/linux/pm.h3
-rw-r--r--kernel/power/user.c4
9 files changed, 50 insertions, 75 deletions
diff --git a/Documentation/power/devices.txt b/Documentation/power/devices.txt
index 88880839ece4..64565aac6e40 100644
--- a/Documentation/power/devices.txt
+++ b/Documentation/power/devices.txt
@@ -520,59 +520,20 @@ Support for power domains is provided through the pwr_domain field of struct
device. This field is a pointer to an object of type struct dev_power_domain,
defined in include/linux/pm.h, providing a set of power management callbacks
analogous to the subsystem-level and device driver callbacks that are executed
-for the given device during all power transitions, in addition to the respective
-subsystem-level callbacks. Specifically, the power domain "suspend" callbacks
-(i.e. ->runtime_suspend(), ->suspend(), ->freeze(), ->poweroff(), etc.) are
-executed after the analogous subsystem-level callbacks, while the power domain
-"resume" callbacks (i.e. ->runtime_resume(), ->resume(), ->thaw(), ->restore,
-etc.) are executed before the analogous subsystem-level callbacks. Error codes
-returned by the "suspend" and "resume" power domain callbacks are ignored.
-
-Power domain ->runtime_idle() callback is executed before the subsystem-level
-->runtime_idle() callback and the result returned by it is not ignored. Namely,
-if it returns error code, the subsystem-level ->runtime_idle() callback will not
-be called and the helper function rpm_idle() executing it will return error
-code. This mechanism is intended to help platforms where saving device state
-is a time consuming operation and should only be carried out if all devices
-in the power domain are idle, before turning off the shared power resource(s).
-Namely, the power domain ->runtime_idle() callback may return error code until
-the pm_runtime_idle() helper (or its asychronous version) has been called for
-all devices in the power domain (it is recommended that the returned error code
-be -EBUSY in those cases), preventing the subsystem-level ->runtime_idle()
-callback from being run prematurely.
-
-The support for device power domains is only relevant to platforms needing to
-use the same subsystem-level (e.g. platform bus type) and device driver power
-management callbacks in many different power domain configurations and wanting
-to avoid incorporating the support for power domains into the subsystem-level
-callbacks. The other platforms need not implement it or take it into account
-in any way.
-
-
-System Devices
---------------
-System devices (sysdevs) follow a slightly different API, which can be found in
-
- include/linux/sysdev.h
- drivers/base/sys.c
-
-System devices will be suspended with interrupts disabled, and after all other
-devices have been suspended. On resume, they will be resumed before any other
-devices, and also with interrupts disabled. These things occur in special
-"sysdev_driver" phases, which affect only system devices.
-
-Thus, after the suspend_noirq (or freeze_noirq or poweroff_noirq) phase, when
-the non-boot CPUs are all offline and IRQs are disabled on the remaining online
-CPU, then a sysdev_driver.suspend phase is carried out, and the system enters a
-sleep state (or a system image is created). During resume (or after the image
-has been created or loaded) a sysdev_driver.resume phase is carried out, IRQs
-are enabled on the only online CPU, the non-boot CPUs are enabled, and the
-resume_noirq (or thaw_noirq or restore_noirq) phase begins.
-
-Code to actually enter and exit the system-wide low power state sometimes
-involves hardware details that are only known to the boot firmware, and
-may leave a CPU running software (from SRAM or flash memory) that monitors
-the system and manages its wakeup sequence.
+for the given device during all power transitions, instead of the respective
+subsystem-level callbacks. Specifically, if a device's pm_domain pointer is
+not NULL, the ->suspend() callback from the object pointed to by it will be
+executed instead of its subsystem's (e.g. bus type's) ->suspend() callback and
+anlogously for all of the remaining callbacks. In other words, power management
+domain callbacks, if defined for the given device, always take precedence over
+the callbacks provided by the device's subsystem (e.g. bus type).
+
+The support for device power management domains is only relevant to platforms
+needing to use the same device driver power management callbacks in many
+different power domain configurations and wanting to avoid incorporating the
+support for power domains into subsystem-level callbacks, for example by
+modifying the platform bus type. Other platforms need not implement it or take
+it into account in any way.
Device Low Power (suspend) States
diff --git a/Documentation/power/runtime_pm.txt b/Documentation/power/runtime_pm.txt
index 654097b130b4..22accb3eb40e 100644
--- a/Documentation/power/runtime_pm.txt
+++ b/Documentation/power/runtime_pm.txt
@@ -566,11 +566,6 @@ to do this is:
pm_runtime_set_active(dev);
pm_runtime_enable(dev);
-The PM core always increments the run-time usage counter before calling the
-->prepare() callback and decrements it after calling the ->complete() callback.
-Hence disabling run-time PM temporarily like this will not cause any run-time
-suspend callbacks to be lost.
-
7. Generic subsystem callbacks
Subsystems may wish to conserve code space by using the set of generic power
diff --git a/drivers/base/power/clock_ops.c b/drivers/base/power/clock_ops.c
index eaa8a854af03..ad367c4139b1 100644
--- a/drivers/base/power/clock_ops.c
+++ b/drivers/base/power/clock_ops.c
@@ -387,7 +387,7 @@ static int pm_runtime_clk_notify(struct notifier_block *nb,
clknb = container_of(nb, struct pm_clk_notifier_block, nb);
switch (action) {
- case BUS_NOTIFY_ADD_DEVICE:
+ case BUS_NOTIFY_BIND_DRIVER:
if (clknb->con_ids[0]) {
for (con_id = clknb->con_ids; *con_id; con_id++)
enable_clock(dev, *con_id);
@@ -395,7 +395,7 @@ static int pm_runtime_clk_notify(struct notifier_block *nb,
enable_clock(dev, NULL);
}
break;
- case BUS_NOTIFY_DEL_DEVICE:
+ case BUS_NOTIFY_UNBOUND_DRIVER:
if (clknb->con_ids[0]) {
for (con_id = clknb->con_ids; *con_id; con_id++)
disable_clock(dev, *con_id);
diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c
index aa6320207745..06f09bf89cb2 100644
--- a/drivers/base/power/main.c
+++ b/drivers/base/power/main.c
@@ -57,7 +57,8 @@ static int async_error;
*/
void device_pm_init(struct device *dev)
{
- dev->power.in_suspend = false;
+ dev->power.is_prepared = false;
+ dev->power.is_suspended = false;
init_completion(&dev->power.completion);
complete_all(&dev->power.completion);
dev->power.wakeup = NULL;
@@ -91,7 +92,7 @@ void device_pm_add(struct device *dev)
pr_debug("PM: Adding info for %s:%s\n",
dev->bus ? dev->bus->name : "No Bus", dev_name(dev));
mutex_lock(&dpm_list_mtx);
- if (dev->parent && dev->parent->power.in_suspend)
+ if (dev->parent && dev->parent->power.is_prepared)
dev_warn(dev, "parent %s should not be sleeping\n",
dev_name(dev->parent));
list_add_tail(&dev->power.entry, &dpm_list);
@@ -511,7 +512,14 @@ static int device_resume(struct device *dev, pm_message_t state, bool async)
dpm_wait(dev->parent, async);
device_lock(dev);
- dev->power.in_suspend = false;
+ /*
+ * This is a fib. But we'll allow new children to be added below
+ * a resumed device, even if the device hasn't been completed yet.
+ */
+ dev->power.is_prepared = false;
+
+ if (!dev->power.is_suspended)
+ goto Unlock;
if (dev->pwr_domain) {
pm_dev_dbg(dev, state, "power domain ");
@@ -548,6 +556,9 @@ static int device_resume(struct device *dev, pm_message_t state, bool async)
}
End:
+ dev->power.is_suspended = false;
+
+ Unlock:
device_unlock(dev);
complete_all(&dev->power.completion);
@@ -670,7 +681,7 @@ void dpm_complete(pm_message_t state)
struct device *dev = to_device(dpm_prepared_list.prev);
get_device(dev);
- dev->power.in_suspend = false;
+ dev->power.is_prepared = false;
list_move(&dev->power.entry, &list);
mutex_unlock(&dpm_list_mtx);
@@ -835,11 +846,11 @@ static int __device_suspend(struct device *dev, pm_message_t state, bool async)
device_lock(dev);
if (async_error)
- goto End;
+ goto Unlock;
if (pm_wakeup_pending()) {
async_error = -EBUSY;
- goto End;
+ goto Unlock;
}
if (dev->pwr_domain) {
@@ -877,6 +888,9 @@ static int __device_suspend(struct device *dev, pm_message_t state, bool async)
}
End:
+ dev->power.is_suspended = !error;
+
+ Unlock:
device_unlock(dev);
complete_all(&dev->power.completion);
@@ -1042,7 +1056,7 @@ int dpm_prepare(pm_message_t state)
put_device(dev);
break;
}
- dev->power.in_suspend = true;
+ dev->power.is_prepared = true;
if (!list_empty(&dev->power.entry))
list_move_tail(&dev->power.entry, &dpm_prepared_list);
put_device(dev);
diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c
index 135df164a4c1..46767c53917a 100644
--- a/drivers/pci/pci-driver.c
+++ b/drivers/pci/pci-driver.c
@@ -624,7 +624,7 @@ static int pci_pm_prepare(struct device *dev)
* system from the sleep state, we'll have to prevent it from signaling
* wake-up.
*/
- pm_runtime_resume(dev);
+ pm_runtime_get_sync(dev);
if (drv && drv->pm && drv->pm->prepare)
error = drv->pm->prepare(dev);
@@ -638,6 +638,8 @@ static void pci_pm_complete(struct device *dev)
if (drv && drv->pm && drv->pm->complete)
drv->pm->complete(dev);
+
+ pm_runtime_put_sync(dev);
}
#else /* !CONFIG_PM_SLEEP */
diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c
index e35a17687c05..aa3cc465a601 100644
--- a/drivers/usb/core/driver.c
+++ b/drivers/usb/core/driver.c
@@ -375,7 +375,7 @@ static int usb_unbind_interface(struct device *dev)
* Just re-enable it without affecting the endpoint toggles.
*/
usb_enable_interface(udev, intf, false);
- } else if (!error && !intf->dev.power.in_suspend) {
+ } else if (!error && !intf->dev.power.is_prepared) {
r = usb_set_interface(udev, intf->altsetting[0].
desc.bInterfaceNumber, 0);
if (r < 0)
@@ -960,7 +960,7 @@ void usb_rebind_intf(struct usb_interface *intf)
}
/* Try to rebind the interface */
- if (!intf->dev.power.in_suspend) {
+ if (!intf->dev.power.is_prepared) {
intf->needs_binding = 0;
rc = device_attach(&intf->dev);
if (rc < 0)
@@ -1107,7 +1107,7 @@ static int usb_resume_interface(struct usb_device *udev,
if (intf->condition == USB_INTERFACE_UNBOUND) {
/* Carry out a deferred switch to altsetting 0 */
- if (intf->needs_altsetting0 && !intf->dev.power.in_suspend) {
+ if (intf->needs_altsetting0 && !intf->dev.power.is_prepared) {
usb_set_interface(udev, intf->altsetting[0].
desc.bInterfaceNumber, 0);
intf->needs_altsetting0 = 0;
diff --git a/include/linux/device.h b/include/linux/device.h
index c66111affca9..553fd37b173b 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -654,13 +654,13 @@ static inline int device_is_registered(struct device *dev)
static inline void device_enable_async_suspend(struct device *dev)
{
- if (!dev->power.in_suspend)
+ if (!dev->power.is_prepared)
dev->power.async_suspend = true;
}
static inline void device_disable_async_suspend(struct device *dev)
{
- if (!dev->power.in_suspend)
+ if (!dev->power.is_prepared)
dev->power.async_suspend = false;
}
diff --git a/include/linux/pm.h b/include/linux/pm.h
index 3160648ccdda..411e4f4be52b 100644
--- a/include/linux/pm.h
+++ b/include/linux/pm.h
@@ -425,7 +425,8 @@ struct dev_pm_info {
pm_message_t power_state;
unsigned int can_wakeup:1;
unsigned int async_suspend:1;
- unsigned int in_suspend:1; /* Owned by the PM core */
+ bool is_prepared:1; /* Owned by the PM core */
+ bool is_suspended:1; /* Ditto */
spinlock_t lock;
#ifdef CONFIG_PM_SLEEP
struct list_head entry;
diff --git a/kernel/power/user.c b/kernel/power/user.c
index 7d02d33be699..42ddbc6f0de6 100644
--- a/kernel/power/user.c
+++ b/kernel/power/user.c
@@ -113,8 +113,10 @@ static int snapshot_open(struct inode *inode, struct file *filp)
if (error)
pm_notifier_call_chain(PM_POST_RESTORE);
}
- if (error)
+ if (error) {
+ free_basic_memory_bitmaps();
atomic_inc(&snapshot_device_available);
+ }
data->frozen = 0;
data->ready = 0;
data->platform_support = 0;