kernel/linux.git/drivers/base/power/sysfs.c, branch linux-5.9.y

PM: sleep: core: Emit changed uevent on wakeup_sysfs_add/remove

2020-07-14T17:19:04+00:00

Udev rules that depend on the power/wakeup attribute don't get triggered correctly if device_set_wakeup_capable is called after the device is created. This can happen for several reasons (driver sets wakeup after device is created, wakeup is changed on parent device, etc) and it seems reasonable to emit a changed event when adding or removing attributes on the device. Signed-off-by: Abhishek Pandit-Subedi Reviewed-by: Greg Kroah-Hartman Reviewed-by: Stephen Boyd Signed-off-by: Rafael J. Wysocki

PM: runtime: Replace pm_runtime_callbacks_present()

2020-05-29T16:03:12+00:00

The name of pm_runtime_callbacks_present() is confusing, because it suggests that the device has PM-runtime callbacks if 'true' is returned by that function, but in fact that may not be the case, so replace it with pm_runtime_has_no_callbacks() which is not ambiguous. No functional impact. Signed-off-by: Rafael J. Wysocki Reviewed-by: Ulf Hansson

drivers/base/power: add dpm_sysfs_change_owner()

2020-02-27T04:07:25+00:00

Add a helper to change the owner of a device's power entries. This needs to happen when the ownership of a device is changed, e.g. when moving network devices between network namespaces. This function will be used to correctly account for ownership changes, e.g. when moving network devices between network namespaces. Reviewed-by: Greg Kroah-Hartman Reviewed-by: "Rafael J. Wysocki" Signed-off-by: Christian Brauner Signed-off-by: David S. Miller

PM / wakeup: Register wakeup class kobj after device is added

2019-08-20T22:25:16+00:00

The device_set_wakeup_enable() function can be called on a device that hasn't been registered with device_add() yet. This allows the device to be in a state where wakeup is enabled for it but the device isn't published to userspace in sysfs yet. After commit c8377adfa781 ("PM / wakeup: Show wakeup sources stats in sysfs"), calling device_set_wakeup_enable() will fail for a device that hasn't been registered with the driver core via device_add(). This is because we try to create sysfs entries for the device and associate a wakeup class kobject with it before the device has been registered. Let's follow a similar approach that device_set_wakeup_capable() takes here and register the wakeup class either from device_set_wakeup_enable() when the device is already registered, or from dpm_sysfs_add() when the device is being registered with the driver core via device_add(). Fixes: c8377adfa781 ("PM / wakeup: Show wakeup sources stats in sysfs") Reported-by: Qian Cai Reviewed-by: Tri Vo Signed-off-by: Stephen Boyd Signed-off-by: Rafael J. Wysocki

drivers: base: power: add proper SPDX identifiers on files that did not have them.

2019-04-04T18:03:40+00:00

There were a few files in the driver core power code that did not have SPDX identifiers on them, so fix that up. At the same time, remove the "free form" text that specified the license of the file, as that is impossible for any tool to properly parse. Cc: "Rafael J. Wysocki" Signed-off-by: Greg Kroah-Hartman

PM-runtime: Call pm_runtime_active|suspended_time() from sysfs

2019-03-07T10:23:17+00:00

Avoid the open-coding of the accounted time acquisition in runtime_active|suspend_time_show() and make them call pm_runtime_active|suspended_time() instead. Note that this change also indirectly avoids holding dev->power.lock around the do_div() computation and the sprintf() call which is an additional improvement. Signed-off-by: Ulf Hansson [ rjw: Changelog ] Signed-off-by: Rafael J. Wysocki

PM / core: Add support to skip power management in device/driver model

2019-02-19T09:42:43+00:00

All device objects in the driver model contain fields that control the handling of various power management activities. However, it's not always useful. There are few instances where pseudo devices are added to the model just to take advantage of many other features like kobjects, udev events, and so on. One such example is cpu devices and their caches. The sysfs for the cpu caches are managed by adding devices with cpu as the parent in cpu_device_create() when secondary cpu is brought online. Generally when the secondary CPUs are hotplugged back in as part of resume from suspend-to-ram, we call cpu_device_create() from the cpu hotplug state machine while the cpu device associated with that CPU is not yet ready to be resumed as the device_resume() call happens bit later. It's not really needed to set the flag is_prepared for cpu devices as they are mostly pseudo device and hotplug framework deals with state machine and not managed through the cpu device. This often results in annoying warning when resuming: Enabling non-boot CPUs ... CPU1: Booted secondary processor cache: parent cpu1 should not be sleeping CPU1 is up CPU2: Booted secondary processor cache: parent cpu2 should not be sleeping CPU2 is up .... and so on. So in order to fix these kind of errors, we could just completely avoid doing any power management related initialisations and operations if they are not used by these devices. Add no_pm flags to indicate that the device doesn't require any sort of PM activities and all of them can be completely skipped. We can use the same flag to also avoid adding not used *power* sysfs entries for these devices. For now, lets use this for cpu cache devices. Reviewed-by: Ulf Hansson Signed-off-by: Sudeep Holla Tested-by: Eugeniu Rosca Signed-off-by: Rafael J. Wysocki

PM-runtime: Replace jiffies-based accounting with ktime-based accounting

2019-01-31T09:45:10+00:00

Replace jiffies-based accounting for runtime_active_time and runtime_suspended_time with ktime-based accounting. This makes the runtime debug counters inline with genpd and other PM subsytems which use ktime-based accounting. Timekeeping is initialized before driver_init(). It's only at that time that PM-runtime can be enabled. Signed-off-by: Thara Gopinath [switch from ktime to raw nsec] Signed-off-by: Vincent Guittot Reviewed-by: Ulf Hansson Signed-off-by: Rafael J. Wysocki

PM / wakeup: Export wakeup_count instead of event_count via sysfs

2018-06-06T07:23:36+00:00

Currently we export event_count instead of wakeup_count via the per-device wakeup_count sysfs attribute. Change it to wakeup_count to make it more meaningful. wakeup_count increments only when events_check_enabled is set, that is whenever writes the current wakeup count to /sys/power/wakeup_count. Also events_check_enabled is cleared on every resume. User space is expected to write to this just before suspend. This way pm_wakeup_event(), when called from IRQs handles, will increment wakeup_count only if we are in system-wide suspend-resume cycle and should give a fair approximation of how many times a device may have triggered a wakeup from system suspend. event_count on the other hand will increment every time pm_wakeup_event() is called irrespective of whether we are in a suspend-resume cycle and some drivers call it on every interrupt which makes it less useful for system wakeup tracking. Signed-off-by: Ravi Chandra Sadineni Acked-by: Pavel Machek [ rjw: Subject & changelog ] Signed-off-by: Rafael J. Wysocki

PM / sysfs: Convert to use DEVICE_ATTR_RO / DEVICE_ATTR_RW

2017-12-05T00:59:57+00:00

Use DEVICE_ATTR_RO() and DEVICE_ATTR_RW() macros instead of open coding them. No functional change intended. Signed-off-by: Andy Shevchenko Acked-by: Pavel Machek Signed-off-by: Rafael J. Wysocki