Since insert_resource() might return an error we don't need
to shadow its error code and would safely propagate to the user.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

It should have been 'management' not 'managemend'.

Fixes: 7945f929 ("drivers: provide devm_platform_ioremap_resource()")
Signed-off-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: NMukesh Ojha <mojha@codeaurora.org>
Reviewed-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

When adding the memory by probing memory block in sysfs interface, there is an
obvious issue that we will unlock the device_hotplug_lock when fails to takes it.

That issue was introduced in Commit 8df1d0e4
("mm/memory_hotplug: make add_memory() take the device_hotplug_lock")

We should drop out in time when fails to take the device_hotplug_lock.

Fixes: 8df1d0e4 ("mm/memory_hotplug: make add_memory() take the device_hotplug_lock")
Reported-by: NYang yingliang <yangyingliang@huawei.com>
Signed-off-by: Nzhong jiang <zhongjiang@huawei.com>
Reviewed-by: NOscar Salvador <osalvador@suse.de>
Reviewed-by: NDavid Hildenbrand <david@redhat.com>
Acked-by: NMichal Hocko <mhocko@suse.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

It is not absolutely clear from the docs how the cleanup path after
device_add() should look like so spell it out explicitly.

No functional changes, just documentation.
Signed-off-by: NBorislav Petkov <bp@suse.de>
Reviewed-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

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" <rafael@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

There were two files in the firmware_loader code that did not have SPDX
identifiers on them, so fix that up.

Cc: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The Makefile in the drivers/base/test/ directory did not have a SPDX
identifier on it, so fix that up.

Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

If user updates any cpu's cpu_capacity, then the new value is going to
be applied to all its online sibling cpus. But this need not to be correct
always, as sibling cpus (in ARM, same micro architecture cpus) would have
different cpu_capacity with different performance characteristics.
So, updating the user supplied cpu_capacity to all cpu siblings
is not correct.

And another problem is, current code assumes that 'all cpus in a cluster
or with same package_id (core_siblings), would have same cpu_capacity'.
But with commit '5bdd2b3f ("arm64: topology: add support to remove
cpu topology sibling masks")', when a cpu hotplugged out, the cpu
information gets cleared in its sibling cpus. So, user supplied
cpu_capacity would be applied to only online sibling cpus at the time.
After that, if any cpu hotplugged in, it would have different cpu_capacity
than its siblings, which breaks the above assumption.

So, instead of mucking around the core sibling mask for user supplied
value, use device-tree to set cpu capacity. And make the cpu_capacity
node as read-only to know the asymmetry between cpus in the system.
While at it, remove cpu_scale_mutex usage, which used for sysfs write
protection.
Tested-by: NDietmar Eggemann <dietmar.eggemann@arm.com>
Tested-by: NQuentin Perret <quentin.perret@arm.com>
Reviewed-by: NQuentin Perret <quentin.perret@arm.com>
Acked-by: NSudeep Holla <sudeep.holla@arm.com>
Signed-off-by: NLingutla Chandrasekhar <clingutla@codeaurora.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

System memory may have caches to help improve access speed to frequently
requested address ranges. While the system provided cache is transparent
to the software accessing these memory ranges, applications can optimize
their own access based on cache attributes.

Provide a new API for the kernel to register these memory-side caches
under the memory node that provides it.

The new sysfs representation is modeled from the existing cpu cacheinfo
attributes, as seen from /sys/devices/system/cpu/<cpu>/cache/.  Unlike CPU
cacheinfo though, the node cache level is reported from the view of the
memory. A higher level number is nearer to the CPU, while lower levels
are closer to the last level memory.

The exported attributes are the cache size, the line size, associativity
indexing, and write back policy, and add the attributes for the system
memory caches to sysfs stable documentation.
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: NBrice Goglin <Brice.Goglin@inria.fr>
Tested-by: NBrice Goglin <Brice.Goglin@inria.fr>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Heterogeneous memory systems provide memory nodes with different latency
and bandwidth performance attributes. Provide a new kernel interface
for subsystems to register the attributes under the memory target
node's initiator access class. If the system provides this information,
applications may query these attributes when deciding which node to
request memory.

The following example shows the new sysfs hierarchy for a node exporting
performance attributes:

  # tree -P "read*|write*"/sys/devices/system/node/nodeY/accessZ/initiators/
  /sys/devices/system/node/nodeY/accessZ/initiators/
  |-- read_bandwidth
  |-- read_latency
  |-- write_bandwidth
  `-- write_latency

The bandwidth is exported as MB/s and latency is reported in
nanoseconds. The values are taken from the platform as reported by the
manufacturer.

Memory accesses from an initiator node that is not one of the memory's
access "Z" initiator nodes linked in the same directory may observe
different performance than reported here. When a subsystem makes use
of this interface, initiators of a different access number may not have
the same performance relative to initiators in other access numbers, or
omitted from the any access class' initiators.

Descriptions for memory access initiator performance access attributes
are added to sysfs stable documentation.
Acked-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Tested-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: NBrice Goglin <Brice.Goglin@inria.fr>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Systems may be constructed with various specialized nodes. Some nodes
may provide memory, some provide compute devices that access and use
that memory, and others may provide both. Nodes that provide memory are
referred to as memory targets, and nodes that can initiate memory access
are referred to as memory initiators.

Memory targets will often have varying access characteristics from
different initiators, and platforms may have ways to express those
relationships. In preparation for these systems, provide interfaces for
the kernel to export the memory relationship among different nodes memory
targets and their initiators with symlinks to each other.

If a system provides access locality for each initiator-target pair, nodes
may be grouped into ranked access classes relative to other nodes. The
new interface allows a subsystem to register relationships of varying
classes if available and desired to be exported.

A memory initiator may have multiple memory targets in the same access
class. The target memory's initiators in a given class indicate the
nodes access characteristics share the same performance relative to other
linked initiator nodes. Each target within an initiator's access class,
though, do not necessarily perform the same as each other.

A memory target node may have multiple memory initiators. All linked
initiators in a target's class have the same access characteristics to
that target.

The following example show the nodes' new sysfs hierarchy for a memory
target node 'Y' with access class 0 from initiator node 'X':

  # symlinks -v /sys/devices/system/node/nodeX/access0/
  relative: /sys/devices/system/node/nodeX/access0/targets/nodeY -> ../../nodeY

  # symlinks -v /sys/devices/system/node/nodeY/access0/
  relative: /sys/devices/system/node/nodeY/access0/initiators/nodeX -> ../../nodeX

The new attributes are added to the sysfs stable documentation.
Reviewed-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Reviewed-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: NBrice Goglin <Brice.Goglin@inria.fr>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Since commit 7934779a ("Driver-Core: disable /sbin/hotplug by
default"), the help text for the /sbin/hotplug fork-bomb says
"This should not be used today [...] creates a high system load, or
[...] out-of-memory situations during bootup".  The rationale for this
was that no recent mainstream system used this anymore (in 2010!).

A few years later, the complete uevent helper support was made optional
in commit 86d56134 ("kobject: Make support for uevent_helper
optional.").  However, if was still left enabled by default, to support
ancient userland.

Time passed by, and nothing should use this anymore, so it can be
disabled by default.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Lockdep warns that prepare_lock and genpd->mlock can cause a deadlock
the deadlock scenario is like following:
First thread is probing cs2000
cs2000_probe()
  clk_register()
    __clk_core_init()
      clk_prepare_lock()                            ----> acquires prepare_lock
        cs2000_recalc_rate()
          i2c_smbus_read_byte_data()
            rcar_i2c_master_xfer()
              dma_request_chan()
                rcar_dmac_of_xlate()
                  rcar_dmac_alloc_chan_resources()
                    pm_runtime_get_sync()
                      __pm_runtime_resume()
                        rpm_resume()
                          rpm_callback()
                            genpd_runtime_resume()   ----> acquires genpd->mlock

Second thread is attaching any device to the same PM domain
genpd_add_device()
  genpd_lock()                                       ----> acquires genpd->mlock
    cpg_mssr_attach_dev()
      of_clk_get_from_provider()
        __of_clk_get_from_provider()
          __clk_create_clk()
            clk_prepare_lock()                       ----> acquires prepare_lock

Since currently no PM provider access genpd's critical section
in .attach_dev, and .detach_dev callbacks, so there is no need to protect
these two callbacks with genpd->mlock.
This patch avoids a potential deadlock by moving out .attach_dev and .detach_dev
from genpd->mlock, so that genpd->mlock won't be held when prepare_lock is acquired
in .attach_dev and .detach_dev
Signed-off-by: NJiada Wang <jiada_wang@mentor.com>
Reviewed-by: NUlf Hansson <ulf.hansson@linaro.org>
Tested-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Fix sparse warning:

drivers/base/swnode.c:475:22: warning: symbol 'software_node_get_parent' was not declared. Should it be static?
drivers/base/swnode.c:484:22: warning: symbol 'software_node_get_next_child' was not declared. Should it be static?
Signed-off-by: NYueHaibing <yuehaibing@huawei.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

After commit d856f39ac1cc ("PM / wakeup: Rework wakeup source timer
cancellation") wakeup_source_drop() is a trivial wrapper around
__pm_relax() and it has no users except for wakeup_source_destroy()
and wakeup_source_trash() which also has no users, so drop it along
with the latter and make wakeup_source_destroy() call __pm_relax()
directly.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>

If wakeup_source_add() is called right after wakeup_source_remove()
for the same wakeup source, timer_setup() may be called for a
potentially scheduled timer which is incorrect.

To avoid that, move the wakeup source timer cancellation from
wakeup_source_drop() to wakeup_source_remove().

Moreover, make wakeup_source_remove() clear the timer function after
canceling the timer to let wakeup_source_not_registered() treat
unregistered wakeup sources in the same way as the ones that have
never been registered.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Cc: 4.4+ <stable@vger.kernel.org> # 4.4+
[ rjw: Subject, changelog, merged two patches together ]
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Remove one unnecessary blank line
Signed-off-by: NDong Aisheng <aisheng.dong@nxp.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

It is strange to only return early for -EBUSY state and left other
errors to be still measured execution time.

As for error cases, the elapsed_ns computed actually is not quite
accurate and meaningful for governor to use. So let's simply return
for all error cases.
Signed-off-by: NDong Aisheng <aisheng.dong@nxp.com>
Reviewed-by: NUlf Hansson <ulf.hansson@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

It's possible a PM domain defines only one state and it does not need
a governor to work. For such case, a warning actually is not necessary.
Signed-off-by: NDong Aisheng <aisheng.dong@nxp.com>
Reviewed-by: NUlf Hansson <ulf.hansson@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Fix a typo in the file description comment.
Signed-off-by: NDong Aisheng <aisheng.dong@nxp.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

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: NUlf Hansson <ulf.hansson@linaro.org>
[ rjw: Changelog ]
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

In a step to consolidate the code for fetching the PM-runtime
active/suspended time for a device, add a common function for that
and make the existing pm_runtime_suspended_time() call it.

Also add a corresponding pm_runtime_active_time() calling the new
common function.
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
[ rjw: Changelog, function rename ]
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Prefix all printk/pr_<level> messages with "PM: " to make the
logging a bit more consistent.

Miscellanea:

 o Convert a few printks to pr_<level>
 o Whitespace to align to open parentheses
 o Remove embedded "PM: " from pr_debugs as pr_fmt adds it
Signed-off-by: NJoe Perches <joe@perches.com>
Reviewed-by: NKees Cook <keescook@chromium.org>
Reviewed-by: NKevin Hilman <khilman@baylibre.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

In platform_device_register_full() the err_alloc label is
misleading, we only ever jump to it if the pdev is NULL,
but it then proceeds to free it, which is a no-op.

Remove the label and simply exit the function immediately.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Reviewed-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This is intended for use with NVDIMMs that are physically persistent
(physically like flash) so that they can be used as a cost-effective
RAM replacement.  Intel Optane DC persistent memory is one
implementation of this kind of NVDIMM.

Currently, a persistent memory region is "owned" by a device driver,
either the "Direct DAX" or "Filesystem DAX" drivers.  These drivers
allow applications to explicitly use persistent memory, generally
by being modified to use special, new libraries. (DIMM-based
persistent memory hardware/software is described in great detail
here: Documentation/nvdimm/nvdimm.txt).

However, this limits persistent memory use to applications which
*have* been modified.  To make it more broadly usable, this driver
"hotplugs" memory into the kernel, to be managed and used just like
normal RAM would be.

To make this work, management software must remove the device from
being controlled by the "Device DAX" infrastructure:

	echo dax0.0 > /sys/bus/dax/drivers/device_dax/unbind

and then tell the new driver that it can bind to the device:

	echo dax0.0 > /sys/bus/dax/drivers/kmem/new_id

After this, there will be a number of new memory sections visible
in sysfs that can be onlined, or that may get onlined by existing
udev-initiated memory hotplug rules.

This rebinding procedure is currently a one-way trip.  Once memory
is bound to "kmem", it's there permanently and can not be
unbound and assigned back to device_dax.

The kmem driver will never bind to a dax device unless the device
is *explicitly* bound to the driver.  There are two reasons for
this: One, since it is a one-way trip, it can not be undone if
bound incorrectly.  Two, the kmem driver destroys data on the
device.  Think of if you had good data on a pmem device.  It
would be catastrophic if you compile-in "kmem", but leave out
the "device_dax" driver.  kmem would take over the device and
write volatile data all over your good data.

This inherits any existing NUMA information for the newly-added
memory from the persistent memory device that came from the
firmware.  On Intel platforms, the firmware has guarantees that
require each socket's persistent memory to be in a separate
memory-only NUMA node.  That means that this patch is not expected
to create NUMA nodes, but will simply hotplug memory into existing
nodes.

Because NUMA nodes are created, the existing NUMA APIs and tools
are sufficient to create policies for applications or memory areas
to have affinity for or an aversion to using this memory.

There is currently some metadata at the beginning of pmem regions.
The section-size memory hotplug restrictions, plus this small
reserved area can cause the "loss" of a section or two of capacity.
This should be fixable in follow-on patches.  But, as a first step,
losing 256MB of memory (worst case) out of hundreds of gigabytes
is a good tradeoff vs. the required code to fix this up precisely.
This calculation is also the reason we export
memory_block_size_bytes().
Signed-off-by: NDave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: NDan Williams <dan.j.williams@intel.com>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Ross Zwisler <zwisler@kernel.org>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: linux-nvdimm@lists.01.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-mm@kvack.org
Cc: Huang Ying <ying.huang@intel.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Yaowei Bai <baiyaowei@cmss.chinamobile.com>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Jerome Glisse <jglisse@redhat.com>
Reviewed-by: NVishal Verma <vishal.l.verma@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

If the provided fwnode is an OF node, set dev.of_node as well.

Also add an of_node_reused flag to struct platform_device_info and copy
this to the new device.  This is needed to avoid pinctrl settings being
requested twice.  See 4e75e1d7 ("driver core: add helper to reuse a
device-tree node") for a longer explanation.

Some drivers are just shims that create extra "glue" devices with the
DT device as parent and have the real driver bind to these.  In these
cases, the glue device needs to get a reference to the original DT node
in order for the main driver to access properties and child nodes.

For example, the sunxi-musb driver creates such a glue device using
platform_device_register_full().  Consequently, devices attached to
this USB interface don't get associated with DT nodes, if present,
the way they do with EHCI.

This change will allow sunxi-musb and similar drivers to easily
propagate the DT node to child devices as required.
Signed-off-by: NMans Rullgard <mans@mansr.com>
Reviewed-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

When no file /path was found, the error code of -ENOENT
enumerated in errno-base.h, is returned. Stating clearly that
the file was not found is much more useful for debugging, So
let's be explicit about that.
Signed-off-by: NJohn Zhao <yuankuiz@codeaurora.org>
Acked-by: NLuis Chamberlain <mcgrof@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

We only build devm_ioremap_resource() if HAS_IOMEM is selected, so this
dependency must cascade down to devm_platform_ioremap_resource().
Signed-off-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

There are currently 1200+ instances of using platform_get_resource()
and devm_ioremap_resource() together in the kernel tree.

This patch wraps these two calls in a single helper. Thanks to that
we don't have to declare a local variable for struct resource * and can
omit the redundant argument for resource type. We also have one
function call less.
Signed-off-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

When rpm_resume() desactivates the autosuspend timer, it should only
try to cancel hrtimer but not wait for the handler to finish, because
both rpm_resume() and pm_suspend_timer_fn() take the power.lock.

A deadlock is possible as follows:

CPU0                              CPU1
rpm_resume()
  spin_lock_irqsave
                                  pm_suspend_timer_fn()
                                    spin_lock_irqsave
  pm_runtime_deactivate_timer()
    hrtimer_cancel()

It is sufficient to call hrtimer_try_to_cancel() from
pm_runtime_deactivate_timer(), because dev->power.timer_expires
reset to 0 by it, so use that function instead of hrtimer_cancel().

Fixes: 8234f673 ("PM-runtime: Switch autosuspend over to using hrtimers")
Reported-by: NSunzhaosheng Sun(Zhaosheng) <sunzhaosheng@hisilicon.com>
Signed-off-by: NVincent Guittot <vincent.guittot@linaro.org>
[ rjw: Changelog ]
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

This is where all the related code already lives.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Commit 4c06c4e6 ("driver core: Fix possible supplier PM-usage
counter imbalance") introduced a regression that causes suppliers
to be suspended prematurely for device links added during consumer
driver probe if the initial PM-runtime status of the consumer is
"suspended" and the consumer is resumed after adding the link and
before pm_runtime_put_suppliers() is called.  In that case,
pm_runtime_put_suppliers() will drop the rpm_active refcount for
the link by one and (since rpm_active is equal to two after the
preceding consumer resume) the supplier's PM-runtime usage counter
will be decremented, which may cause the supplier to suspend even
though the consumer's PM-runtime status is "active".

For this reason, partially revert commit 4c06c4e6 as the problem
it tried to fix needs to be addressed somewhat differently, and
change pm_runtime_get_suppliers() and pm_runtime_put_suppliers() so
that the latter only drops rpm_active references acquired by the
former.  [This requires adding a new field to struct device_link,
but I coulnd't find a cleaner way to address the issue that would
work in all cases.]

This causes pm_runtime_put_suppliers() to effectively ignore device
links added during consumer probe, so device_link_add() doesn't need
to worry about ensuring that suppliers will remain active after
pm_runtime_put_suppliers() for links created with DL_FLAG_RPM_ACTIVE
set and it only needs to bump up rpm_active by one for those links,
so pm_runtime_active_link() is not necessary any more.

Fixes: 4c06c4e6 ("driver core: Fix possible supplier PM-usage counter imbalance")
Reported-by: NJon Hunter <jonathanh@nvidia.com>
Tested-by: NJon Hunter <jonathanh@nvidia.com>
Tested-by: NUlf Hansson <ulf.hansson@linaro.org>
Reviewed-by: NUlf Hansson <ulf.hansson@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: NThierry Reding <treding@nvidia.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Polish the kerneldoc a bit with suggestions from Randy.

v2: Randy found another typo: s/compent/component/
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Ramalingam C <ramalingam.c@intel.com>
Acked-by: NRandy Dunlap <rdunlap@infradead.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

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: NUlf Hansson <ulf.hansson@linaro.org>
Signed-off-by: NSudeep Holla <sudeep.holla@arm.com>
Tested-by: NEugeniu Rosca <erosca@de.adit-jv.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

As of the patch ("PM / Domains: Mark "name" const in
genpd_dev_pm_attach_by_name()") it's clear that the name in
dev_pm_domain_attach_by_name() can be const.  Mark it as so.  This
allows drivers to pass in a name that was declared "const" in a
driver.

Fixes: 27dceb81 ("PM / Domains: Introduce dev_pm_domain_attach_by_name()")
Signed-off-by: NDouglas Anderson <dianders@chromium.org>
Reviewed-by: NStephen Boyd <swboyd@chromium.org>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: NUlf Hansson <ulf.hansson@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The genpd_dev_pm_attach_by_name() simply takes the name and passes it
to of_property_match_string() where the argument is "const char *".
Adding a const here allows a later patch to add a const to
dev_pm_domain_attach_by_name() which allows drivers to pass in a name
that was declared "const" in a driver.

Fixes: 5d6be70a ("PM / Domains: Introduce option to attach a device by name to genpd")
Signed-off-by: NDouglas Anderson <dianders@chromium.org>
Reviewed-by: NStephen Boyd <swboyd@chromium.org>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: NUlf Hansson <ulf.hansson@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

This makes it possible to support drivers that use
fwnode_get_named_child_node() and device_get_named_child_node()
functions.

The node name is for now taken from a device property named
"name". That mimics the old style of naming of the nodes in
devicetree (though with modern flattened DT, the name is
matched against the actual node-name, it used to be done
with a property "name"). In Open Firmware DT the "name"
property is also still being used.
Signed-off-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

If connections between devices are described in OF graph or
ACPI device graph, we can find them by using the
fwnode_graph_*() functions.
Acked-by: NHans de Goede <hdegoede@redhat.com>
Reviewed-by: NAndy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: NJun Li <jun.li@nxp.com>
Tested-by: NJun Li <jun.li@nxp.com>
Signed-off-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

When the connections are defined in firmware, struct
device_connection will have the fwnode member pointing to
the device node (struct fwnode_handle) of the requested
device. The endpoint member for the device names will not be
used at all in that case.
Acked-by: NHans de Goede <hdegoede@redhat.com>
Reviewed-by: NAndy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: NJun Li <jun.li@nxp.com>
Tested-by: NJun Li <jun.li@nxp.com>
Signed-off-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Asynchronous driver probing can help much on kernel fastboot, and
this option can provide a flexible way to optimize and quickly verify
async driver probe.

Also it will help in below cases:
* Some driver actually covers several families of HWs, some of which
  could use async probing while others don't. So we can't simply
  turn on the PROBE_PREFER_ASYNCHRONOUS flag in driver, but use this
  cmdline option, like igb driver async patch discussed at
  https://www.spinics.net/lists/netdev/msg545986.html

* For SOC (System on Chip) with multiple spi or i2c controllers, most
  of the slave spi/i2c devices will be assigned with fixed controller
  number, while async probing may make those controllers get different
  index for each boot, which prevents those controller drivers to be
  async probed. For platforms not using these spi/i2c slave devices,
  they can use this cmdline option to benefit from the async probing.
Suggested-by: NAlexander Duyck <alexander.h.duyck@linux.intel.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: NFeng Tang <feng.tang@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>