<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel/linux.git/drivers/base/power, branch linux-5.11.y</title>
<subtitle>Linux kernel stable tree (mirror)</subtitle>
<id>https://git.radix-linux.su/kernel/linux.git/atom?h=linux-5.11.y</id>
<link rel='self' href='https://git.radix-linux.su/kernel/linux.git/atom?h=linux-5.11.y'/>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/'/>
<updated>2021-05-19T08:29:26+00:00</updated>
<entry>
<title>PM: runtime: Fix unpaired parent child_count for force_resume</title>
<updated>2021-05-19T08:29:26+00:00</updated>
<author>
<name>Tony Lindgren</name>
<email>tony@atomide.com</email>
</author>
<published>2021-05-05T11:09:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=b7fefdce0ed1841291a6f56fef9c9f15190b8d85'/>
<id>urn:sha1:b7fefdce0ed1841291a6f56fef9c9f15190b8d85</id>
<content type='text'>
commit c745253e2a691a40c66790defe85c104a887e14a upstream.

As pm_runtime_need_not_resume() relies also on usage_count, it can return
a different value in pm_runtime_force_suspend() compared to when called in
pm_runtime_force_resume(). Different return values can happen if anything
calls PM runtime functions in between, and causes the parent child_count
to increase on every resume.

So far I've seen the issue only for omapdrm that does complicated things
with PM runtime calls during system suspend for legacy reasons:

omap_atomic_commit_tail() for omapdrm.0
 dispc_runtime_get()
  wakes up 58000000.dss as it's the dispc parent
   dispc_runtime_resume()
    rpm_resume() increases parent child_count
 dispc_runtime_put() won't idle, PM runtime suspend blocked
pm_runtime_force_suspend() for 58000000.dss, !pm_runtime_need_not_resume()
 __update_runtime_status()
system suspended
pm_runtime_force_resume() for 58000000.dss, pm_runtime_need_not_resume()
 pm_runtime_enable() only called because of pm_runtime_need_not_resume()
omap_atomic_commit_tail() for omapdrm.0
 dispc_runtime_get()
  wakes up 58000000.dss as it's the dispc parent
   dispc_runtime_resume()
    rpm_resume() increases parent child_count
 dispc_runtime_put() won't idle, PM runtime suspend blocked
...
rpm_suspend for 58000000.dss but parent child_count is now unbalanced

Let's fix the issue by adding a flag for needs_force_resume and use it in
pm_runtime_force_resume() instead of pm_runtime_need_not_resume().

Additionally omapdrm system suspend could be simplified later on to avoid
lots of unnecessary PM runtime calls and the complexity it adds. The
driver can just use internal functions that are shared between the PM
runtime and system suspend related functions.

Fixes: 4918e1f87c5f ("PM / runtime: Rework pm_runtime_force_suspend/resume()")
Signed-off-by: Tony Lindgren &lt;tony@atomide.com&gt;
Reviewed-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Tested-by: Tomi Valkeinen &lt;tomi.valkeinen@ideasonboard.com&gt;
Cc: 4.16+ &lt;stable@vger.kernel.org&gt; # 4.16+
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>PM: runtime: Fix ordering in pm_runtime_get_suppliers()</title>
<updated>2021-04-07T13:02:31+00:00</updated>
<author>
<name>Adrian Hunter</name>
<email>adrian.hunter@intel.com</email>
</author>
<published>2021-03-26T10:56:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=d0c537873218929667526ecd2a335843f3b4d897'/>
<id>urn:sha1:d0c537873218929667526ecd2a335843f3b4d897</id>
<content type='text'>
commit c0c33442f7203704aef345647e14c2fb86071001 upstream.

rpm_active indicates how many times the supplier usage_count has been
incremented. Consequently it must be updated after pm_runtime_get_sync() of
the supplier, not before.

Fixes: 4c06c4e6cf63 ("driver core: Fix possible supplier PM-usage counter imbalance")
Signed-off-by: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: 5.1+ &lt;stable@vger.kernel.org&gt; # 5.1+
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>PM: runtime: Fix race getting/putting suppliers at probe</title>
<updated>2021-04-07T13:02:31+00:00</updated>
<author>
<name>Adrian Hunter</name>
<email>adrian.hunter@intel.com</email>
</author>
<published>2021-03-26T10:56:19+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=2a59577a9d9e70d40f78bd61f9186cd4defac280'/>
<id>urn:sha1:2a59577a9d9e70d40f78bd61f9186cd4defac280</id>
<content type='text'>
commit 9dfacc54a8661bc8be6e08cffee59596ec59f263 upstream.

pm_runtime_put_suppliers() must not decrement rpm_active unless the
consumer is suspended. That is because, otherwise, it could suspend
suppliers for an active consumer.

That can happen as follows:

 static int driver_probe_device(struct device_driver *drv, struct device *dev)
 {
	int ret = 0;

	if (!device_is_registered(dev))
		return -ENODEV;

	dev-&gt;can_match = true;
	pr_debug("bus: '%s': %s: matched device %s with driver %s\n",
		 drv-&gt;bus-&gt;name, __func__, dev_name(dev), drv-&gt;name);

	pm_runtime_get_suppliers(dev);
	if (dev-&gt;parent)
		pm_runtime_get_sync(dev-&gt;parent);

 At this point, dev can runtime suspend so rpm_put_suppliers() can run,
 rpm_active becomes 1 (the lowest value).

	pm_runtime_barrier(dev);
	if (initcall_debug)
		ret = really_probe_debug(dev, drv);
	else
		ret = really_probe(dev, drv);

 Probe callback can have runtime resumed dev, and then runtime put
 so dev is awaiting autosuspend, but rpm_active is 2.

	pm_request_idle(dev);

	if (dev-&gt;parent)
		pm_runtime_put(dev-&gt;parent);

	pm_runtime_put_suppliers(dev);

 Now pm_runtime_put_suppliers() will put the supplier
 i.e. rpm_active 2 -&gt; 1, but consumer can still be active.

	return ret;
 }

Fix by checking the runtime status. For any status other than
RPM_SUSPENDED, rpm_active can be considered to be "owned" by
rpm_[get/put]_suppliers() and pm_runtime_put_suppliers() need do nothing.

Reported-by: Asutosh Das &lt;asutoshd@codeaurora.org&gt;
Fixes: 4c06c4e6cf63 ("driver core: Fix possible supplier PM-usage counter imbalance")
Signed-off-by: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: 5.1+ &lt;stable@vger.kernel.org&gt; # 5.1+
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>PM: runtime: Defer suspending suppliers</title>
<updated>2021-03-30T12:30:25+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2021-03-19T14:47:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=8b39e4df84a01ffab0165e985a39034076d11011'/>
<id>urn:sha1:8b39e4df84a01ffab0165e985a39034076d11011</id>
<content type='text'>
[ Upstream commit 5244f5e2d801259af877ee759e8c22364c607072 ]

Because the PM-runtime status of the device is not updated in
__rpm_callback(), attempts to suspend the suppliers of the given
device triggered by the rpm_put_suppliers() call in there may
cause a supplier to be suspended completely before the status of
the consumer is updated to RPM_SUSPENDED, which is confusing.

To avoid that (1) modify __rpm_callback() to only decrease the
PM-runtime usage counter of each supplier and (2) make rpm_suspend()
try to suspend the suppliers after changing the consumer's status to
RPM_SUSPENDED, in analogy with the device's parent.

Link: https://lore.kernel.org/linux-pm/CAPDyKFqm06KDw_p8WXsM4dijDbho4bb6T4k50UqqvR1_COsp8g@mail.gmail.com/
Fixes: 21d5c57b3726 ("PM / runtime: Use device links")
Reported-by: elaine.zhang &lt;zhangqing@rock-chips.com&gt;
Diagnosed-by: Ulf Hansson &lt;ulf.hansson@linaro.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;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>Revert "PM: runtime: Update device status before letting suppliers suspend"</title>
<updated>2021-03-24T10:53:58+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2021-03-19T14:47:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=1a33f12678fc766111c616e3e133275813e0c2c6'/>
<id>urn:sha1:1a33f12678fc766111c616e3e133275813e0c2c6</id>
<content type='text'>
commit 0cab893f409c53634d0d818fa414641cbcdb0dab upstream.

Revert commit 44cc89f76464 ("PM: runtime: Update device status
before letting suppliers suspend") that introduced a race condition
into __rpm_callback() which allowed a concurrent rpm_resume() to
run and resume the device prematurely after its status had been
changed to RPM_SUSPENDED by __rpm_callback().

Fixes: 44cc89f76464 ("PM: runtime: Update device status before letting suppliers suspend")
Link: https://lore.kernel.org/linux-pm/24dfb6fc-5d54-6ee2-9195-26428b7ecf8a@intel.com/
Reported-by: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: 4.10+ &lt;stable@vger.kernel.org&gt; # 4.10+
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Reviewed-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>PM: runtime: Update device status before letting suppliers suspend</title>
<updated>2021-03-09T10:21:20+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2021-02-25T18:23:27+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=2bc3dca7898a93bcea937a0a2faf22917278261a'/>
<id>urn:sha1:2bc3dca7898a93bcea937a0a2faf22917278261a</id>
<content type='text'>
commit 44cc89f764646b2f1f2ea5d1a08b230131707851 upstream.

Because the PM-runtime status of the device is not updated in
__rpm_callback(), attempts to suspend the suppliers of the given
device triggered by rpm_put_suppliers() called by it may fail.

Fix this by making __rpm_callback() update the device's status to
RPM_SUSPENDED before calling rpm_put_suppliers() if the current
status of the device is RPM_SUSPENDING and the callback just invoked
by it has returned 0 (success).

While at it, modify the code in __rpm_callback() to always check
the device's PM-runtime status under its PM lock.

Link: https://lore.kernel.org/linux-pm/CAPDyKFqm06KDw_p8WXsM4dijDbho4bb6T4k50UqqvR1_COsp8g@mail.gmail.com/
Fixes: 21d5c57b3726 ("PM / runtime: Use device links")
Reported-by: Elaine Zhang &lt;zhangqing@rock-chips.com&gt;
Diagnosed-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Tested-by: Elaine Zhang &lt;zhangiqng@rock-chips.com&gt;
Reviewed-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Cc: 4.10+ &lt;stable@vger.kernel.org&gt; # 4.10+
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>Merge branches 'pm-sleep', 'pm-acpi', 'pm-domains' and 'powercap'</title>
<updated>2020-12-15T14:26:14+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2020-12-15T14:26:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=42b4ca04cbfde952e7be132ffc7226890323bbe1'/>
<id>urn:sha1:42b4ca04cbfde952e7be132ffc7226890323bbe1</id>
<content type='text'>
* pm-sleep:
  PM: sleep: Add dev_wakeup_path() helper
  PM / suspend: fix kernel-doc markup
  PM: sleep: Print driver flags for all devices during suspend/resume

* pm-acpi:
  PM: ACPI: Refresh wakeup device power configuration every time
  PM: ACPI: PCI: Drop acpi_pm_set_bridge_wakeup()
  PM: ACPI: reboot: Use S5 for reboot

* pm-domains:
  PM: domains: create debugfs nodes when adding power domains
  PM: domains: replace -ENOTSUPP with -EOPNOTSUPP

* powercap:
  powercap: Adjust printing the constraint name with new line
  powercap: RAPL: Add AMD Fam19h RAPL support
  powercap: Add AMD Fam17h RAPL support
  powercap/intel_rapl_msr: Convert rapl_msr_priv into pointer
  x86/msr-index: sort AMD RAPL MSRs by address
</content>
</entry>
<entry>
<title>Merge branches 'pm-cpuidle' and 'pm-em'</title>
<updated>2020-12-15T14:25:37+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2020-12-15T14:25:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=4c5744a0c4fcb878e1500e77d53722197c0a3f7c'/>
<id>urn:sha1:4c5744a0c4fcb878e1500e77d53722197c0a3f7c</id>
<content type='text'>
* pm-cpuidle:
  cpuidle: Select polling interval based on a c-state with a longer target residency
  cpuidle: psci: Enable suspend-to-idle for PSCI OSI mode
  PM: domains: Enable dev_pm_genpd_suspend|resume() for suspend-to-idle
  PM: domains: Rename pm_genpd_syscore_poweroff|poweron()

* pm-em:
  PM / EM: Micro optimization in em_cpu_energy
  PM: EM: Update Energy Model with new flag indicating power scale
  PM: EM: update the comments related to power scale
  PM: EM: Clarify abstract scale usage for power values in Energy Model
</content>
</entry>
<entry>
<title>Merge branch 'opp/linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm</title>
<updated>2020-12-14T19:26:17+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2020-12-14T19:26:17+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=f0f6dbaf06f4329dbd07594ffcd55edf27ee4b45'/>
<id>urn:sha1:f0f6dbaf06f4329dbd07594ffcd55edf27ee4b45</id>
<content type='text'>
Pull OPP (Operating Performance Points) updates for 5.11-rc1 from
Viresh Kumar:

"This contains the following updates:

 - Allow empty (node-less) OPP tables in DT for passing just the
   dependency related information (Nicola Mazzucato).

 - Fix a potential lockdep in OPP core and other OPP core cleanups
   (Viresh Kumar).

 - Don't abuse dev_pm_opp_get_opp_table() to create an OPP table, fix
   cpufreq-dt driver for the same (Viresh Kumar).

 - dev_pm_opp_put_regulators() accepts a NULL argument now, updates to
   all the users as well (Viresh Kumar)."

* 'opp/linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm:
  opp: of: Allow empty opp-table with opp-shared
  dt-bindings: opp: Allow empty OPP tables
  media: venus: dev_pm_opp_put_*() accepts NULL argument
  drm/panfrost: dev_pm_opp_put_*() accepts NULL argument
  drm/lima: dev_pm_opp_put_*() accepts NULL argument
  PM / devfreq: exynos: dev_pm_opp_put_*() accepts NULL argument
  cpufreq: qcom-cpufreq-nvmem: dev_pm_opp_put_*() accepts NULL argument
  cpufreq: dt: dev_pm_opp_put_regulators() accepts NULL argument
  opp: Allow dev_pm_opp_put_*() APIs to accept NULL opp_table
  opp: Don't create an OPP table from dev_pm_opp_get_opp_table()
  cpufreq: dt: Don't (ab)use dev_pm_opp_get_opp_table() to create OPP table
  opp: Reduce the size of critical section in _opp_kref_release()
  opp: Don't return opp_dev from _find_opp_dev()
  opp: Allocate the OPP table outside of opp_table_lock
  opp: Always add entries in dev_list with opp_table-&gt;lock held
</content>
</entry>
<entry>
<title>PM: domains: create debugfs nodes when adding power domains</title>
<updated>2020-12-11T18:35:49+00:00</updated>
<author>
<name>Thierry Strudel</name>
<email>tstrudel@google.com</email>
</author>
<published>2020-12-08T19:19:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=718072ceb211833f3c71724f49d733d636067191'/>
<id>urn:sha1:718072ceb211833f3c71724f49d733d636067191</id>
<content type='text'>
debugfs nodes were created in genpd_debug_init alled in late_initcall
preventing power domains registered though loadable modules to have
a debugfs entry.

Create/remove debugfs nodes when the power domain is added/removed
to/from the internal gpd_list.

Signed-off-by: Thierry Strudel &lt;tstrudel@google.com&gt;
Reviewed-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.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>
</entry>
</feed>
