<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/include/linux/pm_runtime.h, branch v6.4-rc1</title>
<subtitle>Linux kernel for Apalis and Colibri modules</subtitle>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/'/>
<entry>
<title>PM: Improve EXPORT_*_DEV_PM_OPS macros</title>
<updated>2022-10-04T18:52:38+00:00</updated>
<author>
<name>Paul Cercueil</name>
<email>paul@crapouillou.net</email>
</author>
<published>2022-08-08T17:40:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=34e1ed189fab1b7533befb266b96051104c1deb6'/>
<id>34e1ed189fab1b7533befb266b96051104c1deb6</id>
<content type='text'>
Update the _EXPORT_DEV_PM_OPS() internal macro. It was not used anywhere
outside pm.h and pm_runtime.h, so it is safe to update it.

Before, this macro would take a few parameters to be used as sleep and
runtime callbacks. This made it unsuitable to use with different
callbacks, for instance the "noirq" ones.

It is now semantically different: instead of creating a conditionally
exported dev_pm_ops structure, it only contains part of the definition.

This macro should however never be used directly (hence the trailing
underscore). Instead, the following four macros are provided:
- EXPORT_DEV_PM_OPS(name)
- EXPORT_GPL_DEV_PM_OPS(name)
- EXPORT_NS_DEV_PM_OPS(name, ns)
- EXPORT_NS_GPL_DEV_PM_OPS(name, ns)

For instance, it is now possible to conditionally export noirq
suspend/resume PM functions like this:

EXPORT_GPL_DEV_PM_OPS(foo_pm_ops) = {
    NOIRQ_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
};

The existing helper macros EXPORT_*_SIMPLE_DEV_PM_OPS() and
EXPORT_*_RUNTIME_DEV_PM_OPS() have been updated to use these new macros.

Signed-off-by: Paul Cercueil &lt;paul@crapouillou.net&gt;
Reviewed-by: Jonathan Cameron &lt;Jonathan.Cameron@huawei.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Update the _EXPORT_DEV_PM_OPS() internal macro. It was not used anywhere
outside pm.h and pm_runtime.h, so it is safe to update it.

Before, this macro would take a few parameters to be used as sleep and
runtime callbacks. This made it unsuitable to use with different
callbacks, for instance the "noirq" ones.

It is now semantically different: instead of creating a conditionally
exported dev_pm_ops structure, it only contains part of the definition.

This macro should however never be used directly (hence the trailing
underscore). Instead, the following four macros are provided:
- EXPORT_DEV_PM_OPS(name)
- EXPORT_GPL_DEV_PM_OPS(name)
- EXPORT_NS_DEV_PM_OPS(name, ns)
- EXPORT_NS_GPL_DEV_PM_OPS(name, ns)

For instance, it is now possible to conditionally export noirq
suspend/resume PM functions like this:

EXPORT_GPL_DEV_PM_OPS(foo_pm_ops) = {
    NOIRQ_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
};

The existing helper macros EXPORT_*_SIMPLE_DEV_PM_OPS() and
EXPORT_*_RUNTIME_DEV_PM_OPS() have been updated to use these new macros.

Signed-off-by: Paul Cercueil &lt;paul@crapouillou.net&gt;
Reviewed-by: Jonathan Cameron &lt;Jonathan.Cameron@huawei.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>PM: runtime: Redefine pm_runtime_release_supplier()</title>
<updated>2022-07-01T19:04:02+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2022-06-27T18:42:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=07358194badf73e267289b40b761f5dc56928eab'/>
<id>07358194badf73e267289b40b761f5dc56928eab</id>
<content type='text'>
Instead of passing an extra bool argument to pm_runtime_release_supplier(),
make its callers take care of triggering a runtime-suspend of the
supplier device as needed.

No expected functional impact.

Suggested-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Reviewed-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Cc: 5.1+ &lt;stable@vger.kernel.org&gt; # 5.1+
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Instead of passing an extra bool argument to pm_runtime_release_supplier(),
make its callers take care of triggering a runtime-suspend of the
supplier device as needed.

No expected functional impact.

Suggested-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Reviewed-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Cc: 5.1+ &lt;stable@vger.kernel.org&gt; # 5.1+
</pre>
</div>
</content>
</entry>
<entry>
<title>PM: core: Add NS varients of EXPORT[_GPL]_SIMPLE_DEV_PM_OPS and runtime pm equiv</title>
<updated>2022-04-05T18:16:34+00:00</updated>
<author>
<name>Jonathan Cameron</name>
<email>Jonathan.Cameron@huawei.com</email>
</author>
<published>2022-04-01T14:06:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=a8e2512efc65892a1cbf608d9c03c8bcbe5a623a'/>
<id>a8e2512efc65892a1cbf608d9c03c8bcbe5a623a</id>
<content type='text'>
As more drivers start to use namespaces, we need to have varients of these
useful macros that allow the export to be in a particular namespace.

Signed-off-by: Jonathan Cameron &lt;Jonathan.Cameron@huawei.com&gt;
Cc: Paul Cercueil &lt;paul@crapouillou.net&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
As more drivers start to use namespaces, we need to have varients of these
useful macros that allow the export to be in a particular namespace.

Signed-off-by: Jonathan Cameron &lt;Jonathan.Cameron@huawei.com&gt;
Cc: Paul Cercueil &lt;paul@crapouillou.net&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>PM: runtime: Have devm_pm_runtime_enable() handle pm_runtime_dont_use_autosuspend()</title>
<updated>2022-03-04T17:26:54+00:00</updated>
<author>
<name>Douglas Anderson</name>
<email>dianders@chromium.org</email>
</author>
<published>2022-02-23T16:34:48+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=b4060db9251f919506e4d672737c6b8ab9a84701'/>
<id>b4060db9251f919506e4d672737c6b8ab9a84701</id>
<content type='text'>
The PM Runtime docs say:

  Drivers in -&gt;remove() callback should undo the runtime PM changes done
  in -&gt;probe(). Usually this means calling pm_runtime_disable(),
  pm_runtime_dont_use_autosuspend() etc.

From grepping code, it's clear that many people aren't aware of the
need to call pm_runtime_dont_use_autosuspend().

When brainstorming solutions, one idea that came up was to leverage
the new-ish devm_pm_runtime_enable() function. The idea here is that:

 * When the devm action is called we know that the driver is being
   removed. It's the perfect time to undo the use_autosuspend.

 * The code of pm_runtime_dont_use_autosuspend() already handles the
   case of being called when autosuspend wasn't enabled.

Suggested-by: Laurent Pinchart &lt;laurent.pinchart@ideasonboard.com&gt;
Signed-off-by: Douglas Anderson &lt;dianders@chromium.org&gt;
Reviewed-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The PM Runtime docs say:

  Drivers in -&gt;remove() callback should undo the runtime PM changes done
  in -&gt;probe(). Usually this means calling pm_runtime_disable(),
  pm_runtime_dont_use_autosuspend() etc.

From grepping code, it's clear that many people aren't aware of the
need to call pm_runtime_dont_use_autosuspend().

When brainstorming solutions, one idea that came up was to leverage
the new-ish devm_pm_runtime_enable() function. The idea here is that:

 * When the devm action is called we know that the driver is being
   removed. It's the perfect time to undo the use_autosuspend.

 * The code of pm_runtime_dont_use_autosuspend() already handles the
   case of being called when autosuspend wasn't enabled.

Suggested-by: Laurent Pinchart &lt;laurent.pinchart@ideasonboard.com&gt;
Signed-off-by: Douglas Anderson &lt;dianders@chromium.org&gt;
Reviewed-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>PM: runtime: Add EXPORT[_GPL]_RUNTIME_DEV_PM_OPS macros</title>
<updated>2022-01-12T18:59:05+00:00</updated>
<author>
<name>Paul Cercueil</name>
<email>paul@crapouillou.net</email>
</author>
<published>2022-01-07T18:17:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=d59ff7d9d84b03d22c5107f794e28fc8e1fce3a6'/>
<id>d59ff7d9d84b03d22c5107f794e28fc8e1fce3a6</id>
<content type='text'>
Similar to EXPORT[_GPL]_SIMPLE_DEV_PM_OPS, but for users with runtime-PM
suspend/resume callbacks.

Signed-off-by: Paul Cercueil &lt;paul@crapouillou.net&gt;
Acked-by: Jonathan Cameron &lt;Jonathan.Cameron@huawei.com&gt;
Reviewed-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Similar to EXPORT[_GPL]_SIMPLE_DEV_PM_OPS, but for users with runtime-PM
suspend/resume callbacks.

Signed-off-by: Paul Cercueil &lt;paul@crapouillou.net&gt;
Acked-by: Jonathan Cameron &lt;Jonathan.Cameron@huawei.com&gt;
Reviewed-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>PM: runtime: Add DEFINE_RUNTIME_DEV_PM_OPS() macro</title>
<updated>2022-01-12T18:59:05+00:00</updated>
<author>
<name>Paul Cercueil</name>
<email>paul@crapouillou.net</email>
</author>
<published>2022-01-07T18:17:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=9d8619190031af0a314bee865262d8975473e4dd'/>
<id>9d8619190031af0a314bee865262d8975473e4dd</id>
<content type='text'>
A lot of drivers create a dev_pm_ops struct with the system sleep
suspend/resume callbacks set to pm_runtime_force_suspend() and
pm_runtime_force_resume().

These drivers can now use the DEFINE_RUNTIME_DEV_PM_OPS() macro, which
will use pm_runtime_force_{suspend,resume}() as the system sleep
callbacks, while having the same dead code removal characteristic that
is already provided by DEFINE_SIMPLE_DEV_PM_OPS().

Signed-off-by: Paul Cercueil &lt;paul@crapouillou.net&gt;
Acked-by: Jonathan Cameron &lt;Jonathan.Cameron@huawei.com&gt;
Reviewed-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
A lot of drivers create a dev_pm_ops struct with the system sleep
suspend/resume callbacks set to pm_runtime_force_suspend() and
pm_runtime_force_resume().

These drivers can now use the DEFINE_RUNTIME_DEV_PM_OPS() macro, which
will use pm_runtime_force_{suspend,resume}() as the system sleep
callbacks, while having the same dead code removal characteristic that
is already provided by DEFINE_SIMPLE_DEV_PM_OPS().

Signed-off-by: Paul Cercueil &lt;paul@crapouillou.net&gt;
Acked-by: Jonathan Cameron &lt;Jonathan.Cameron@huawei.com&gt;
Reviewed-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>PM: runtime: Add safety net to supplier device release</title>
<updated>2021-12-17T15:25:14+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2021-12-10T16:10:13+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=d1579e61192e0e686faa4208500ef4c3b529b16c'/>
<id>d1579e61192e0e686faa4208500ef4c3b529b16c</id>
<content type='text'>
Because refcount_dec_not_one() returns true if the target refcount
becomes saturated, it is generally unsafe to use its return value as
a loop termination condition, but that is what happens when a device
link's supplier device is released during runtime PM suspend
operations and on device link removal.

To address this, introduce pm_runtime_release_supplier() to be used
in the above cases which will check the supplier device's runtime
PM usage counter in addition to the refcount_dec_not_one() return
value, so the loop can be terminated in case the rpm_active refcount
value becomes invalid, and update the code in question to use it as
appropriate.

This change is not expected to have any visible functional impact.

Reported-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Acked-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Acked-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Because refcount_dec_not_one() returns true if the target refcount
becomes saturated, it is generally unsafe to use its return value as
a loop termination condition, but that is what happens when a device
link's supplier device is released during runtime PM suspend
operations and on device link removal.

To address this, introduce pm_runtime_release_supplier() to be used
in the above cases which will check the supplier device's runtime
PM usage counter in addition to the refcount_dec_not_one() return
value, so the loop can be terminated in case the rpm_active refcount
value becomes invalid, and update the code in question to use it as
appropriate.

This change is not expected to have any visible functional impact.

Reported-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Acked-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Acked-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>PM: runtime: Fix pm_runtime_active() kerneldoc comment</title>
<updated>2021-12-08T14:21:55+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2021-12-03T16:19:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=444dd878e85fb33fcfb2682cfdab4c236f33ea3e'/>
<id>444dd878e85fb33fcfb2682cfdab4c236f33ea3e</id>
<content type='text'>
The kerneldoc comment of pm_runtime_active() does not reflect the
behavior of the function, so update it accordingly.

Fixes: 403d2d116ec0 ("PM: runtime: Add kerneldoc comments to multiple helpers")
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Reviewed-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The kerneldoc comment of pm_runtime_active() does not reflect the
behavior of the function, so update it accordingly.

Fixes: 403d2d116ec0 ("PM: runtime: Add kerneldoc comments to multiple helpers")
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Reviewed-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>PM: runtime: add devm_pm_runtime_enable helper</title>
<updated>2021-08-26T18:27:51+00:00</updated>
<author>
<name>Dmitry Baryshkov</name>
<email>dmitry.baryshkov@linaro.org</email>
</author>
<published>2021-07-31T19:50:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=b3636a3a2c51715736d3ec45f635ed03191962ce'/>
<id>b3636a3a2c51715736d3ec45f635ed03191962ce</id>
<content type='text'>
A typical code pattern for pm_runtime_enable() call is to call it in the
_probe function and to call pm_runtime_disable() both from _probe error
path and from _remove function. For some drivers the whole remove
function would consist of the call to pm_remove_disable().

Add helper function to replace this bolierplate piece of code. Calling
devm_pm_runtime_enable() removes the need for calling
pm_runtime_disable() both in the probe()'s error path and in the
remove() function.

Signed-off-by: Dmitry Baryshkov &lt;dmitry.baryshkov@linaro.org&gt;
Link: https://lore.kernel.org/r/20210731195034.979084-2-dmitry.baryshkov@linaro.org
Acked-by: Rafael J. Wysocki &lt;rafael@kernel.org&gt;
Signed-off-by: Stephen Boyd &lt;sboyd@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
A typical code pattern for pm_runtime_enable() call is to call it in the
_probe function and to call pm_runtime_disable() both from _probe error
path and from _remove function. For some drivers the whole remove
function would consist of the call to pm_remove_disable().

Add helper function to replace this bolierplate piece of code. Calling
devm_pm_runtime_enable() removes the need for calling
pm_runtime_disable() both in the probe()'s error path and in the
remove() function.

Signed-off-by: Dmitry Baryshkov &lt;dmitry.baryshkov@linaro.org&gt;
Link: https://lore.kernel.org/r/20210731195034.979084-2-dmitry.baryshkov@linaro.org
Acked-by: Rafael J. Wysocki &lt;rafael@kernel.org&gt;
Signed-off-by: Stephen Boyd &lt;sboyd@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>PM: runtime: document common mistake with pm_runtime_get_sync()</title>
<updated>2021-05-31T12:17:13+00:00</updated>
<author>
<name>Krzysztof Kozlowski</name>
<email>krzysztof.kozlowski@canonical.com</email>
</author>
<published>2021-05-26T16:22:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=c58e7ed28b4534ed073371843d03c433d6a9fe34'/>
<id>c58e7ed28b4534ed073371843d03c433d6a9fe34</id>
<content type='text'>
pm_runtime_get_sync(), contradictory to intuition, does not drop the
runtime PM usage counter on errors which lead to several wrong usages in
drivers (missing the put).  pm_runtime_resume_and_get() was added as a
better implementation so document the preference of using it, hoping it
will stop bad patterns.

Suggested-by: Marek Szyprowski &lt;m.szyprowski@samsung.com&gt;
Signed-off-by: Krzysztof Kozlowski &lt;krzysztof.kozlowski@canonical.com&gt;
[ rjw: Documentation change edits ]
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
pm_runtime_get_sync(), contradictory to intuition, does not drop the
runtime PM usage counter on errors which lead to several wrong usages in
drivers (missing the put).  pm_runtime_resume_and_get() was added as a
better implementation so document the preference of using it, hoping it
will stop bad patterns.

Suggested-by: Marek Szyprowski &lt;m.szyprowski@samsung.com&gt;
Signed-off-by: Krzysztof Kozlowski &lt;krzysztof.kozlowski@canonical.com&gt;
[ rjw: Documentation change edits ]
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
</feed>
