'parent' is always overwritten before getting used and there is no need
to initialize it with NULL.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It is sometimes useful to know that a device is on the deferred probe
list rather than, say, not having a driver available. Expose this
information to user-space.
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If the device has no links to suppliers that should be used for
runtime PM (links with DEVICE_LINK_PM_RUNTIME set), there is no
reason to walk the list of suppliers for that device during
runtime suspend and resume.
Add a simple mechanism to detect that case and possibly avoid the
extra unnecessary overhead.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Modify the runtime PM framework to use device links to ensure that
supplier devices will not be suspended if any of their consumer
devices are active.
The idea is to reference count suppliers on the consumer's resume
and drop references to them on its suspend. The information on
whether or not the supplier has been reference counted by the
consumer's (runtime) resume is stored in a new field (rpm_active)
in the link object for each link.
It may be necessary to clean up those references when the
supplier is unbinding and that's why the links whose status is
DEVICE_LINK_SUPPLIER_UNBIND are skipped by the runtime suspend
and resume code.
The above means that if the consumer device is probed in the
runtime-active state, the supplier has to be resumed and reference
counted by device_link_add() so the code works as expected on its
(runtime) suspend. There is a new flag, DEVICE_LINK_RPM_ACTIVE,
to tell device_link_add() about that (in which case the caller
is responsible for making sure that the consumer really will
be runtime-active when runtime PM is enabled for it).
The other new link flag, DEVICE_LINK_PM_RUNTIME, tells the core
whether or not the link should be used for runtime PM at all.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently, there is a problem with taking functional dependencies
between devices into account.
What I mean by a "functional dependency" is when the driver of device
B needs device A to be functional and (generally) its driver to be
present in order to work properly. This has certain consequences
for power management (suspend/resume and runtime PM ordering) and
shutdown ordering of these devices. In general, it also implies that
the driver of A needs to be working for B to be probed successfully
and it cannot be unbound from the device before the B's driver.
Support for representing those functional dependencies between
devices is added here to allow the driver core to track them and act
on them in certain cases where applicable.
The argument for doing that in the driver core is that there are
quite a few distinct use cases involving device dependencies, they
are relatively hard to get right in a driver (if one wants to
address all of them properly) and it only gets worse if multiplied
by the number of drivers potentially needing to do it. Morever, at
least one case (asynchronous system suspend/resume) cannot be handled
in a single driver at all, because it requires the driver of A to
wait for B to suspend (during system suspend) and the driver of B to
wait for A to resume (during system resume).
For this reason, represent dependencies between devices as "links",
with the help of struct device_link objects each containing pointers
to the "linked" devices, a list node for each of them, status
information, flags, and an RCU head for synchronization.
Also add two new list heads, representing the lists of links to the
devices that depend on the given one (consumers) and to the devices
depended on by it (suppliers), and a "driver presence status" field
(needed for figuring out initial states of device links) to struct
device.
The entire data structure consisting of all of the lists of link
objects for all devices is protected by a mutex (for link object
addition/removal and for list walks during device driver probing
and removal) and by SRCU (for list walking in other case that will
be introduced by subsequent change sets). If CONFIG_SRCU is not
selected, however, an rwsem is used for protecting the entire data
structure.
In addition, each link object has an internal status field whose
value reflects whether or not drivers are bound to the devices
pointed to by the link or probing/removal of their drivers is in
progress etc. That field is only modified under the device links
mutex, but it may be read outside of it in some cases (introduced by
subsequent change sets), so modifications of it are annotated with
WRITE_ONCE().
New links are added by calling device_link_add() which takes three
arguments: pointers to the devices in question and flags. In
particular, if DL_FLAG_STATELESS is set in the flags, the link status
is not to be taken into account for this link and the driver core
will not manage it. In turn, if DL_FLAG_AUTOREMOVE is set in the
flags, the driver core will remove the link automatically when the
consumer device driver unbinds from it.
One of the actions carried out by device_link_add() is to reorder
the lists used for device shutdown and system suspend/resume to
put the consumer device along with all of its children and all of
its consumers (and so on, recursively) to the ends of those lists
in order to ensure the right ordering between all of the supplier
and consumer devices.
For this reason, it is not possible to create a link between two
devices if the would-be supplier device already depends on the
would-be consumer device as either a direct descendant of it or a
consumer of one of its direct descendants or one of its consumers
and so on.
There are two types of link objects, persistent and non-persistent.
The persistent ones stay around until one of the target devices is
deleted, while the non-persistent ones are removed automatically when
the consumer driver unbinds from its device (ie. they are assumed to
be valid only as long as the consumer device has a driver bound to
it). Persistent links are created by default and non-persistent
links are created when the DL_FLAG_AUTOREMOVE flag is passed
to device_link_add().
Both persistent and non-persistent device links can be deleted
with an explicit call to device_link_del().
Links created without the DL_FLAG_STATELESS flag set are managed
by the driver core using a simple state machine. There are 5 states
each link can be in: DORMANT (unused), AVAILABLE (the supplier driver
is present and functional), CONSUMER_PROBE (the consumer driver is
probing), ACTIVE (both supplier and consumer drivers are present and
functional), and SUPPLIER_UNBIND (the supplier driver is unbinding).
The driver core updates the link state automatically depending on
what happens to the linked devices and for each link state specific
actions are taken in addition to that.
For example, if the supplier driver unbinds from its device, the
driver core will also unbind the drivers of all of its consumers
automatically under the assumption that they cannot function
properly without the supplier. Analogously, the driver core will
only allow the consumer driver to bind to its device if the
supplier driver is present and functional (ie. the link is in
the AVAILABLE state). If that's not the case, it will rely on
the existing deferred probing mechanism to wait for the supplier
driver to become available.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull driver core updates from Greg KH:
"Here are the "big" driver core patches for 4.9-rc1. Also in here are a
number of debugfs fixes that cropped up due to the changes that
happened in 4.8 for that filesystem. Overall, nothing major, just a
few fixes and cleanups.
All of these have been in linux-next with no reported issues"
* tag 'driver-core-4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (23 commits)
drivers: dma-coherent: Move spinlock in dma_alloc_from_coherent()
drivers: dma-coherent: Fix DMA coherent size for less than page
MAINTAINERS: extend firmware_class maintainer list
debugfs: propagate release() call result
driver-core: platform: Catch errors from calls to irq_get_irq_data
sysfs print name of undiscoverable attribute group
carl9170: fix debugfs crashes
b43legacy: fix debugfs crash
b43: fix debugfs crash
debugfs: introduce a public file_operations accessor
device core: Remove deprecated create_singlethread_workqueue
drivers/base dmam_declare_coherent_memory leaks
platform: don't return 0 from platform_get_irq[_byname]() on error
cpu: clean up register_cpu func
dma-mapping: use vma_pages().
drivers: dma-coherent: use vma_pages().
attribute_container: Fix typo
base: soc: make it explicitly non-modular
drivers: base: dma-mapping: page align the size when unmap_kernel_range
platform driver: fix use-after-free in platform_device_del()
...
The global mutex of 'gdp_mutex' is used to serialize creating/querying
glue dir and its cleanup. Turns out it isn't a perfect way because
part(kobj_kset_leave()) of the actual cleanup action() is done inside
the release handler of the glue dir kobject. That means gdp_mutex has
to be held before releasing the last reference count of the glue dir
kobject.
This patch moves glue dir's cleanup after kobject_del() in device_del()
for avoiding the race.
Cc: Yijing Wang <wangyijing@huawei.com>
Reported-by: Chandra Sekhar Lingutla <clingutla@codeaurora.org>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If device_add_property_set() is called for a device, a secondary fwnode
is allocated and assigned to the device but currently not freed once the
device is removed.
This can be triggered on Apple Macs if a Thunderbolt device is plugged
in on boot since Apple's NHI EFI driver sets a number of properties for
that device which are leaked on unplug.
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
If multiple devices share single firmware node like it is case with MFD
devices, the same firmware node (ACPI) is assigned to all of them. The
function also modifies the shared firmware node in order to preserve
secondary firmware node of the device in question.
If the new device which is sharing the firmware node does not have
secondary node it will be NULL which will be assigned to the secondary node
of the shared firmware node losing all built-in properties.
Prevent this by setting the secondary firmware node only if the replacement
is non-NULL.
Print also warning if someone tries to overwrite secondary node that has
already been assigned.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
For now, in function device_add, the new device will be forced to
inherit the numa node of its parent. But this will override the device's
numa node which configured in devicetree.
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull power management and ACPI updates from Rafael Wysocki:
"From the number of commits perspective, the biggest items are ACPICA
and cpufreq changes with the latter taking the lead (over 50 commits).
On the cpufreq front, there are many cleanups and minor fixes in the
core and governors, driver updates etc. We also have a new cpufreq
driver for Mediatek MT8173 chips.
ACPICA mostly updates its debug infrastructure and adds a number of
fixes and cleanups for a good measure.
The Operating Performance Points (OPP) framework is updated with new
DT bindings and support for them among other things.
We have a few updates of the generic power domains framework and a
reorganization of the ACPI device enumeration code and bus type
operations.
And a lot of fixes and cleanups all over.
Included is one branch from the MFD tree as it contains some
PM-related driver core and ACPI PM changes a few other commits are
based on.
Specifics:
- ACPICA update to upstream revision 20150818 including method
tracing extensions to allow more in-depth AML debugging in the
kernel and a number of assorted fixes and cleanups (Bob Moore, Lv
Zheng, Markus Elfring).
- ACPI sysfs code updates and a documentation update related to AML
method tracing (Lv Zheng).
- ACPI EC driver fix related to serialized evaluations of _Qxx
methods and ACPI tools updates allowing the EC userspace tool to be
built from the kernel source (Lv Zheng).
- ACPI processor driver updates preparing it for future introduction
of CPPC support and ACPI PCC mailbox driver updates (Ashwin
Chaugule).
- ACPI interrupts enumeration fix for a regression related to the
handling of IRQ attribute conflicts between MADT and the ACPI
namespace (Jiang Liu).
- Fixes related to ACPI device PM (Mika Westerberg, Srinidhi
Kasagar).
- ACPI device registration code reorganization to separate the
sysfs-related code and bus type operations from the rest (Rafael J
Wysocki).
- Assorted cleanups in the ACPI core (Jarkko Nikula, Mathias Krause,
Andy Shevchenko, Rafael J Wysocki, Nicolas Iooss).
- ACPI cpufreq driver and ia64 cpufreq driver fixes and cleanups (Pan
Xinhui, Rafael J Wysocki).
- cpufreq core cleanups on top of the previous changes allowing it to
preseve its sysfs directories over system suspend/resume (Viresh
Kumar, Rafael J Wysocki, Sebastian Andrzej Siewior).
- cpufreq fixes and cleanups related to governors (Viresh Kumar).
- cpufreq updates (core and the cpufreq-dt driver) related to the
turbo/boost mode support (Viresh Kumar, Bartlomiej Zolnierkiewicz).
- New DT bindings for Operating Performance Points (OPP), support for
them in the OPP framework and in the cpufreq-dt driver plus related
OPP framework fixes and cleanups (Viresh Kumar).
- cpufreq powernv driver updates (Shilpasri G Bhat).
- New cpufreq driver for Mediatek MT8173 (Pi-Cheng Chen).
- Assorted cpufreq driver (speedstep-lib, sfi, integrator) cleanups
and fixes (Abhilash Jindal, Andrzej Hajda, Cristian Ardelean).
- intel_pstate driver updates including Skylake-S support, support
for enabling HW P-states per CPU and an additional vendor bypass
list entry (Kristen Carlson Accardi, Chen Yu, Ethan Zhao).
- cpuidle core fixes related to the handling of coupled idle states
(Xunlei Pang).
- intel_idle driver updates including Skylake Client support and
support for freeze-mode-specific idle states (Len Brown).
- Driver core updates related to power management (Andy Shevchenko,
Rafael J Wysocki).
- Generic power domains framework fixes and cleanups (Jon Hunter,
Geert Uytterhoeven, Rajendra Nayak, Ulf Hansson).
- Device PM QoS framework update to allow the latency tolerance
setting to be exposed to user space via sysfs (Mika Westerberg).
- devfreq support for PPMUv2 in Exynos5433 and a fix for an incorrect
exynos-ppmu DT binding (Chanwoo Choi, Javier Martinez Canillas).
- System sleep support updates (Alan Stern, Len Brown, SungEun Kim).
- rockchip-io AVS support updates (Heiko Stuebner).
- PM core clocks support fixup (Colin Ian King).
- Power capping RAPL driver update including support for Skylake H/S
and Broadwell-H (Radivoje Jovanovic, Seiichi Ikarashi).
- Generic device properties framework fixes related to the handling
of static (driver-provided) property sets (Andy Shevchenko).
- turbostat and cpupower updates (Len Brown, Shilpasri G Bhat,
Shreyas B Prabhu)"
* tag 'pm+acpi-4.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (180 commits)
cpufreq: speedstep-lib: Use monotonic clock
cpufreq: powernv: Increase the verbosity of OCC console messages
cpufreq: sfi: use kmemdup rather than duplicating its implementation
cpufreq: drop !cpufreq_driver check from cpufreq_parse_governor()
cpufreq: rename cpufreq_real_policy as cpufreq_user_policy
cpufreq: remove redundant 'policy' field from user_policy
cpufreq: remove redundant 'governor' field from user_policy
cpufreq: update user_policy.* on success
cpufreq: use memcpy() to copy policy
cpufreq: remove redundant CPUFREQ_INCOMPATIBLE notifier event
cpufreq: mediatek: Add MT8173 cpufreq driver
dt-bindings: mediatek: Add MT8173 CPU DVFS clock bindings
PM / Domains: Fix typo in description of genpd_dev_pm_detach()
PM / Domains: Remove unusable governor dummies
PM / Domains: Make pm_genpd_init() available to modules
PM / domains: Align column headers and data in pm_genpd_summary output
powercap / RAPL: disable the 2nd power limit properly
tools: cpupower: Fix error when running cpupower monitor
PM / OPP: Drop unlikely before IS_ERR(_OR_NULL)
PM / OPP: Fix static checker warning (broken 64bit big endian systems)
...
Pull irq updates from Thomas Gleixner:
"This updated pull request does not contain the last few GIC related
patches which were reported to cause a regression. There is a fix
available, but I let it breed for a couple of days first.
The irq departement provides:
- new infrastructure to support non PCI based MSI interrupts
- a couple of new irq chip drivers
- the usual pile of fixlets and updates to irq chip drivers
- preparatory changes for removal of the irq argument from interrupt
flow handlers
- preparatory changes to remove IRQF_VALID"
* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (129 commits)
irqchip/imx-gpcv2: IMX GPCv2 driver for wakeup sources
irqchip: Add bcm2836 interrupt controller for Raspberry Pi 2
irqchip: Add documentation for the bcm2836 interrupt controller
irqchip/bcm2835: Add support for being used as a second level controller
irqchip/bcm2835: Refactor handle_IRQ() calls out of MAKE_HWIRQ
PCI: xilinx: Fix typo in function name
irqchip/gic: Ensure gic_cpu_if_up/down() programs correct GIC instance
irqchip/gic: Only allow the primary GIC to set the CPU map
PCI/MSI: pci-xgene-msi: Consolidate chained IRQ handler install/remove
unicore32/irq: Prepare puv3_gpio_handler for irq argument removal
tile/pci_gx: Prepare trio_handle_level_irq for irq argument removal
m68k/irq: Prepare irq handlers for irq argument removal
C6X/megamode-pic: Prepare megamod_irq_cascade for irq argument removal
blackfin: Prepare irq handlers for irq argument removal
arc/irq: Prepare idu_cascade_isr for irq argument removal
sparc/irq: Use access helper irq_data_get_affinity_mask()
sparc/irq: Use helper irq_data_get_irq_handler_data()
parisc/irq: Use access helper irq_data_get_affinity_mask()
mn10300/irq: Use access helper irq_data_get_affinity_mask()
irqchip/i8259: Prepare i8259_irq_dispatch for irq argument removal
...
Now device's shutdown sequence is performed in reverse order of their
registration in devices_kset list and this sequence corresponds to the
reverse device's creation order. So, devices_kset data tracks
"parent<-child" device's dependencies only.
Unfortunately, that's not enough and causes problems in case of
implementing board's specific shutdown procedures. For example [1]:
"DRA7XX_evm uses PCF8575 and one of the PCF output lines feeds to
MMC/SD and this line should be driven high in order for the MMC/SD to
be detected. This line is modelled as regulator and the hsmmc driver
takes care of enabling and disabling it. In the case of 'reboot',
during shutdown path as part of it's cleanup process the hsmmc driver
disables this regulator. This makes MMC boot not functional."
To handle this issue the .shutdown() callback could be implemented
for PCF8575 device where corresponding GPIO pins will be configured to
states, required for correct warm/cold reset. This can be achieved
only when all .shutdown() callbacks have been called already for all
PCF8575's consumers. But devices_kset is not filled correctly now:
devices_kset: Device61 4e000000.dmm
devices_kset: Device62 48070000.i2c
devices_kset: Device63 48072000.i2c
devices_kset: Device64 48060000.i2c
devices_kset: Device65 4809c000.mmc
...
devices_kset: Device102 fixedregulator-sd
...
devices_kset: Device181 0-0020 // PCF8575
devices_kset: Device182 gpiochip496
devices_kset: Device183 0-0021 // PCF8575
devices_kset: Device184 gpiochip480
As can be seen from above .shutdown() callback for PCF8575 will be called
before its consumers, which, in turn means, that any changes of PCF8575
GPIO's pins will be or unsafe or overwritten later by GPIO's consumers.
The problem can be solved if devices_kset list will be filled not only
according device creation order, but also according device's probing
order to track "supplier<-consumer" dependencies also.
Hence, as a fix, lets add devices_kset_move_last(),
devices_kset_move_before(), devices_kset_move_after() and call them
from device_move() and also add call of devices_kset_move_last() in
really_probe(). After this change all entries in devices_kset will
be sorted according to device's creation ("parent<-child") and
probing ("supplier<-consumer") order.
devices_kset after:
devices_kset: Device121 48070000.i2c
devices_kset: Device122 i2c-0
...
devices_kset: Device147 regulator.24
devices_kset: Device148 0-0020
devices_kset: Device149 gpiochip496
devices_kset: Device150 0-0021
devices_kset: Device151 gpiochip480
devices_kset: Device152 0-0019
...
devices_kset: Device372 fixedregulator-sd
devices_kset: Device373 regulator.29
devices_kset: Device374 4809c000.mmc
devices_kset: Device375 mmc0
[1] http://www.spinics.net/lists/linux-mmc/msg29825.html
Cc: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The new function device_for_each_child_reverse() is helpful to traverse the
registered devices in a reversed order, e.g. in the case when an operation on
each device should be done first on the last added device, then on one before
last and so on.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Pull power management and ACPI updates from Rafael Wysocki:
"These are mostly fixes and cleanups all over, although there are a few
items that sort of fall into the new feature category.
First off, we have new callbacks for PM domains that should help us to
handle some issues related to device initialization in a better way.
There also is some consolidation in the unified device properties API
area allowing us to use that inferface for accessing data coming from
platform initialization code in addition to firmware-provided data.
We have some new device/CPU IDs in a few drivers, support for new
chips and a new cpufreq driver too.
Specifics:
- Generic PM domains support update including new PM domain callbacks
to handle device initialization better (Russell King, Rafael J
Wysocki, Kevin Hilman)
- Unified device properties API update including a new mechanism for
accessing data provided by platform initialization code (Rafael J
Wysocki, Adrian Hunter)
- ARM cpuidle update including ARM32/ARM64 handling consolidation
(Daniel Lezcano)
- intel_idle update including support for the Silvermont Core in the
Baytrail SOC and for the Airmont Core in the Cherrytrail and
Braswell SOCs (Len Brown, Mathias Krause)
- New cpufreq driver for Hisilicon ACPU (Leo Yan)
- intel_pstate update including support for the Knights Landing chip
(Dasaratharaman Chandramouli, Kristen Carlson Accardi)
- QorIQ cpufreq driver update (Tang Yuantian, Arnd Bergmann)
- powernv cpufreq driver update (Shilpasri G Bhat)
- devfreq update including Tegra support changes (Tomeu Vizoso,
MyungJoo Ham, Chanwoo Choi)
- powercap RAPL (Running-Average Power Limit) driver update including
support for Intel Broadwell server chips (Jacob Pan, Mathias Krause)
- ACPI device enumeration update related to the handling of the
special PRP0001 device ID allowing DT-style 'compatible' property
to be used for ACPI device identification (Rafael J Wysocki)
- ACPI EC driver update including limited _DEP support (Lan Tianyu,
Lv Zheng)
- ACPI backlight driver update including a new mechanism to allow
native backlight handling to be forced on non-Windows 8 systems and
a new quirk for Lenovo Ideapad Z570 (Aaron Lu, Hans de Goede)
- New Windows Vista compatibility quirk for Sony VGN-SR19XN (Chen Yu)
- Assorted ACPI fixes and cleanups (Aaron Lu, Martin Kepplinger,
Masanari Iida, Mika Westerberg, Nan Li, Rafael J Wysocki)
- Fixes related to suspend-to-idle for the iTCO watchdog driver and
the ACPI core system suspend/resume code (Rafael J Wysocki, Chen Yu)
- PM tracing support for the suspend phase of system suspend/resume
transitions (Zhonghui Fu)
- Configurable delay for the system suspend/resume testing facility
(Brian Norris)
- PNP subsystem cleanups (Peter Huewe, Rafael J Wysocki)"
* tag 'pm+acpi-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (74 commits)
ACPI / scan: Fix NULL pointer dereference in acpi_companion_match()
ACPI / scan: Rework modalias creation when "compatible" is present
intel_idle: mark cpu id array as __initconst
powercap / RAPL: mark rapl_ids array as __initconst
powercap / RAPL: add ID for Broadwell server
intel_pstate: Knights Landing support
intel_pstate: remove MSR test
cpufreq: fix qoriq uniprocessor build
ACPI / scan: Take the PRP0001 position in the list of IDs into account
ACPI / scan: Simplify acpi_match_device()
ACPI / scan: Generalize of_compatible matching
device property: Introduce firmware node type for platform data
device property: Make it possible to use secondary firmware nodes
PM / watchdog: iTCO: stop watchdog during system suspend
cpufreq: hisilicon: add acpu driver
ACPI / EC: Call acpi_walk_dep_device_list() after installing EC opregion handler
cpufreq: powernv: Report cpu frequency throttling
intel_idle: Add support for the Airmont Core in the Cherrytrail and Braswell SOCs
intel_idle: Update support for Silvermont Core in Baytrail SOC
PM / devfreq: tegra: Register governor on module init
...
Add a secondary pointer to struct fwnode_handle so as to make it
possible for a device to have two firmware nodes associated with
it at the same time, for example, an ACPI node and a node with
a set of properties provided by platform initialization code.
In the future that will allow device property lookup to fall back
from the primary firmware node to the secondary one if the given
property is not present there to make it easier to provide defaults
for device properties used by device drivers.
Introduce two helper routines, set_primary_fwnode() and
set_secondary_fwnode() allowing callers to add a primary/secondary
firmware node to the given device in such a way that
(1) If there's only one firmware node for that device, it will be
pointed to by the device's firmware node pointer.
(2) If both the primary and secondary firmware nodes are present,
the primary one will be pointed to by the device's firmware
node pointer, while the secondary one will be pointed to by the
primary node's secondary pointer.
(3) If one of these nodes is removed (by calling one of the new
nelpers with NULL as the second argument), the other one will
be preserved.
Make ACPI use set_primary_fwnode() for attaching its firmware nodes
to devices.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
So I've been annoyed lately with having a bunch of devices such as i2c
eeproms (for use by VPDs, server world !) and other bits and pieces that
I want to be able to identify from userspace, and possibly provide
additional data about from FW.
Basically, it boils down to correlating the sysfs device with the OF
tree device node, so that user space can use device-tree info such as
additional "location" or "label" (or whatever else we can come up with)
propreties to identify a given device, or get some attributes of use
about it, etc...
Now, so far, we've done that in some subsystem in a fairly ad-hoc basis
using "devspec" properties. For example, PCI creates them if it can
correlate the probed device with a DT node. Some powerpc specific busses
do that too.
However, i2c doesn't and it would be nice to have something more generic
since technically any device can have a corresponding device tree node.
This patch adds an "of_node" symlink to devices that have a non-NULL
dev->of_node pointer, the patch is pretty trivial and seems to work just
fine for me.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The put_device() function tests whether its argument is NULL and then
returns immediately. Thus the test around the call is not needed.
This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Viresh Kumar
Heiko Carstens
Ingo Molnar
Dan Williams
Greg Kroah-Hartman
Lukas Wunner
Ben Hutchings
Rafael J. Wysocki
Linus Torvalds
Ming Lei
Mika Westerberg
Zhen Lei
Grygorii Strashko
Andy Shevchenko
Jiang Liu
Rasmus Villemoes
Benjamin Herrenschmidt
Markus Elfring