snowball/legacy-kernel.git/drivers/base, branch igloo-dev

PM: Limit race conditions between runtime PM and system sleep (v2)

2011-10-27T14:35:15+00:00

One of the roles of the PM core is to prevent different PM callbacks executed for the same device object from racing with each other. Unfortunately, after commit e8665002477f0278f84f898145b1f141ba26ee26 (PM: Allow pm_runtime_suspend() to succeed during system suspend) runtime PM callbacks may be executed concurrently with system suspend/resume callbacks for the same device. The main reason for commit e8665002477f0278f84f898145b1f141ba26ee26 was that some subsystems and device drivers wanted to use runtime PM helpers, pm_runtime_suspend() and pm_runtime_put_sync() in particular, for carrying out the suspend of devices in their .suspend() callbacks. However, as it's been determined recently, there are multiple reasons not to do so, inlcuding: * The caller really doesn't control the runtime PM usage counters, because user space can access them through sysfs and effectively block runtime PM. That means using pm_runtime_suspend() or pm_runtime_get_sync() to suspend devices during system suspend may or may not work. * If a driver calls pm_runtime_suspend() from its .suspend() callback, it causes the subsystem's .runtime_suspend() callback to be executed, which leads to the call sequence: subsys->suspend(dev) driver->suspend(dev) pm_runtime_suspend(dev) subsys->runtime_suspend(dev) recursive from the subsystem's point of view. For some subsystems that may actually work (e.g. the platform bus type), but for some it will fail in a rather spectacular fashion (e.g. PCI). In each case it means a layering violation. * Both the subsystem and the driver can provide .suspend_noirq() callbacks for system suspend that can do whatever the .runtime_suspend() callbacks do just fine, so it really isn't necessary to call pm_runtime_suspend() during system suspend. * The runtime PM's handling of wakeup devices is usually different from the system suspend's one, so .runtime_suspend() may simply be inappropriate for system suspend. * System suspend is supposed to work even if CONFIG_PM_RUNTIME is unset. * The runtime PM workqueue is frozen before system suspend, so if whatever the driver is going to do during system suspend depends on it, that simply won't work. Still, there is a good reason to allow pm_runtime_resume() to succeed during system suspend and resume (for instance, some subsystems and device drivers may legitimately use it to ensure that their devices are in full-power states before suspending them). Moreover, there is no reason to prevent runtime PM callbacks from being executed in parallel with the system suspend/resume .prepare() and .complete() callbacks and the code removed by commit e8665002477f0278f84f898145b1f141ba26ee26 went too far in this respect. On the other hand, runtime PM callbacks, including .runtime_resume(), must not be executed during system suspend's "late" stage of suspending devices and during system resume's "early" device resume stage. Taking all of the above into consideration, make the PM core acquire a runtime PM reference to every device and resume it if there's a runtime PM resume request pending right before executing the subsystem-level .suspend() callback for it. Make the PM core drop references to all devices right after executing the subsystem-level .resume() callbacks for them. Additionally, make the PM core disable the runtime PM framework for all devices during system suspend, after executing the subsystem-level .suspend() callbacks for them, and enable the runtime PM framework for all devices during system resume, right before executing the subsystem-level .resume() callbacks for them. Conflicts: drivers/base/power/main.c Change-Id: I184431a2e6663222685098d869272b5e84b93c11 Signed-off-by: Rafael J. Wysocki Acked-by: Kevin Hilman Signed-off-by: Ulf Hansson Reviewed-on: http://gerrit.lud.stericsson.com/gerrit/35337 Reviewed-by: QABUILD Reviewed-by: Linus WALLEIJ

PM: Introduce generic "noirq" callback routines for subsystems (v2)

2011-10-27T14:34:55+00:00

Introduce generic "noirq" power management callback routines for subsystems in addition to the "regular" generic PM callback routines. The new routines will be used, among other things, for implementing system-wide PM transitions support for generic PM domains. Signed-off-by: Rafael J. Wysocki Change-Id: I345a1c6d221b402f349837581681bc7b5c464ea9 Reviewed-on: http://gerrit.lud.stericsson.com/gerrit/35335 Reviewed-by: QABUILD Reviewed-by: Linus WALLEIJ Tested-by: Ulf HANSSON

Revert duplicate merge of "PM: Add support for device power domains"

2011-09-19T14:00:16+00:00

This reverts commit 56e7ee03819e3a43da7eb13428c19714c4d914c2: commit 56e7ee03819e3a43da7eb13428c19714c4d914c2 Author: Rafael J. Wysocki AuthorDate: Wed Feb 16 21:53:17 2011 +0100 Commit: Philippe Langlais CommitDate: Fri Jul 22 15:36:46 2011 +0200 PM: Add support for device power domains The correct commit is already present in 3.0, and the above was incorrectly merged, leading to power domain callbacks being called twice. The correct commit is: commit 7538e3db6e015e890825fbd9f8659952896ddd5b Author: Rafael J. Wysocki AuthorDate: Wed Feb 16 21:53:17 2011 +0100 Commit: Rafael J. Wysocki CommitDate: Tue Mar 15 00:43:16 2011 +0100 PM: Add support for device power domains

Merge linux-linaro-3.0-2011.07-1-android-1 into..

2011-09-19T13:40:54+00:00

..linux-linaro-3.0-2011.07-1_glk3.0 Conflicts: arch/arm/common/Makefile drivers/misc/Kconfig drivers/misc/Makefile kernel/printk.c Change-Id: I126f34edb1879981909072beefb2738cad26f951

Export SoC info through sysfs

2011-09-19T13:14:56+00:00

Common base to export System-on-Chip related informations through sysfs. Creation of a "socinfo" directory under /sys/. Creation of SoC information entries. Signed-off-by: Maxime COQUELIN Change-Id: I8f9cbccbed07293d26974e9df3bf1102d42e561c Reviewed-on: http://gerrit.lud.stericsson.com/gerrit/18178 Reviewed-by: Linus WALLEIJ

PM: Add support for device power domains

2011-09-19T13:14:37+00:00

The platform bus type is often used to handle Systems-on-a-Chip (SoC) where all devices are represented by objects of type struct platform_device. In those cases the same "platform" device driver may be used with multiple different system configurations, but the actions needed to put the devices it handles into a low-power state and back into the full-power state may depend on the design of the given SoC. The driver, however, cannot possibly include all the information necessary for the power management of its device on all the systems it is used with. Moreover, the device hierarchy in its current form also is not suitable for representing this kind of information. The patch below attempts to address this problem by introducing objects of type struct dev_power_domain that can be used for representing power domains within a SoC. Every struct dev_power_domain object provides a sets of device power management callbacks that can be used to perform what's needed for device power management in addition to the operations carried out by the device's driver and subsystem. Namely, if a struct dev_power_domain object is pointed to by the pwr_domain field in a struct device, the callbacks provided by its ops member will be executed in addition to the corresponding callbacks provided by the device's subsystem and driver during all power transitions. Signed-off-by: Rafael J. Wysocki Tested-and-acked-by: Kevin Hilman ST-Ericsson Linux next: - ST-Ericsson ID: ER323382 ST-Ericsson FOSS-OUT ID: Trivial Change-Id: I1f21456339aaa75905694bf4d87912b762c9d85e Reviewed-on: http://gerrit.lud.stericsson.com/gerrit/16674 Tested-by: Rabin VINCENT Reviewed-by: Jonas ABERG

Merge branch 'upstream/linaro-3.0' into linaro-android-3.0

2011-07-25T16:58:06+00:00

Merge commit 'v3.0-rc7' into android-3.0

2011-07-13T03:10:37+00:00

mm: Move definition of MIN_MEMORY_BLOCK_SIZE to a header

2011-07-12T01:08:01+00:00

The macro MIN_MEMORY_BLOCK_SIZE is currently defined twice in two .c files, and I need it in a third one to fix a powerpc bug, so let's first move it into a header Signed-off-by: Benjamin Herrenschmidt Acked-by: Ingo Molnar

PM: Reintroduce dropped call to check_wakeup_irqs

2011-07-11T08:51:49+00:00

Patch 2e711c04dbbf7a7732a3f7073b1fc285d12b369d (PM: Remove sysdev suspend, resume and shutdown operations) deleted sysdev_suspend(), which was being relied on to call check_wakeup_irqs() in suspend. If check_wakeup_irqs() is not called, wake interrupts that are pending when suspend is entered may be lost. It also breaks IRQCHIP_MASK_ON_SUSPEND, which is handled in check_wakeup_irqs(). This patch adds a call to check_wakeup_irqs() in syscore_suspend(), similar to what was deleted in sysdev_suspend(). Signed-off-by: Colin Cross Signed-off-by: Rafael J. Wysocki