<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/drivers/acpi, branch v5.1.2</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>ACPI / LPSS: Use acpi_lpss_* instead of acpi_subsys_* functions for hibernate</title>
<updated>2019-05-11T05:49:55+00:00</updated>
<author>
<name>Hans de Goede</name>
<email>hdegoede@redhat.com</email>
</author>
<published>2019-04-18T11:39:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=cebdbdda4850e4ce844c2c2d03d838a43abbd63a'/>
<id>cebdbdda4850e4ce844c2c2d03d838a43abbd63a</id>
<content type='text'>
commit c8afd03486c26accdda4846e5561aa3f8e862a9d upstream.

Commit 48402cee6889 ("ACPI / LPSS: Resume BYT/CHT I2C controllers from
resume_noirq") makes acpi_lpss_{suspend_late,resume_early}() bail early
on BYT/CHT as resume_from_noirq is set.

This means that on resume from hibernate dw_i2c_plat_resume() doesn't get
called by the restore_early callback, acpi_lpss_resume_early(). Instead it
should be called by the restore_noirq callback matching how things are done
when resume_from_noirq is set and we are doing a regular resume.

Change the restore_noirq callback to acpi_lpss_resume_noirq so that
dw_i2c_plat_resume() gets properly called when resume_from_noirq is set
and we are resuming from hibernate.

Likewise also change the poweroff_noirq callback so that
dw_i2c_plat_suspend gets called properly.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202139
Fixes: 48402cee6889 ("ACPI / LPSS: Resume BYT/CHT I2C controllers from resume_noirq")
Reported-by: Kai-Heng Feng &lt;kai.heng.feng@canonical.com&gt;
Signed-off-by: Hans de Goede &lt;hdegoede@redhat.com&gt;
Cc: 4.20+ &lt;stable@vger.kernel.org&gt; # 4.20+
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>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit c8afd03486c26accdda4846e5561aa3f8e862a9d upstream.

Commit 48402cee6889 ("ACPI / LPSS: Resume BYT/CHT I2C controllers from
resume_noirq") makes acpi_lpss_{suspend_late,resume_early}() bail early
on BYT/CHT as resume_from_noirq is set.

This means that on resume from hibernate dw_i2c_plat_resume() doesn't get
called by the restore_early callback, acpi_lpss_resume_early(). Instead it
should be called by the restore_noirq callback matching how things are done
when resume_from_noirq is set and we are doing a regular resume.

Change the restore_noirq callback to acpi_lpss_resume_noirq so that
dw_i2c_plat_resume() gets properly called when resume_from_noirq is set
and we are resuming from hibernate.

Likewise also change the poweroff_noirq callback so that
dw_i2c_plat_suspend gets called properly.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202139
Fixes: 48402cee6889 ("ACPI / LPSS: Resume BYT/CHT I2C controllers from resume_noirq")
Reported-by: Kai-Heng Feng &lt;kai.heng.feng@canonical.com&gt;
Signed-off-by: Hans de Goede &lt;hdegoede@redhat.com&gt;
Cc: 4.20+ &lt;stable@vger.kernel.org&gt; # 4.20+
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>Revert "ACPICA: Clear status of GPEs before enabling them"</title>
<updated>2019-04-30T18:03:44+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2019-04-30T09:18:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=2c2a2fb1e2a9256714338875bede6b7cbd4b9542'/>
<id>2c2a2fb1e2a9256714338875bede6b7cbd4b9542</id>
<content type='text'>
Revert commit c8b1917c8987 ("ACPICA: Clear status of GPEs before
enabling them") that causes problems with Thunderbolt controllers
to occur if a dock device is connected at init time (the xhci_hcd
and thunderbolt modules crash which prevents peripherals connected
through them from working).

Commit c8b1917c8987 effectively causes commit ecc1165b8b74 ("ACPICA:
Dispatch active GPEs at init time") to get undone, so the problem
addressed by commit ecc1165b8b74 appears again as a result of it.

Fixes: c8b1917c8987 ("ACPICA: Clear status of GPEs before enabling them")
Link: https://lore.kernel.org/lkml/s5hy33siofw.wl-tiwai@suse.de/T/#u
Link: https://bugzilla.opensuse.org/show_bug.cgi?id=1132943
Reported-by: Michael Hirmke &lt;opensuse@mike.franken.de&gt;
Reported-by: Takashi Iwai &lt;tiwai@suse.de&gt;
Cc: 4.17+ &lt;stable@vger.kernel.org&gt; # 4.17+
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>
Revert commit c8b1917c8987 ("ACPICA: Clear status of GPEs before
enabling them") that causes problems with Thunderbolt controllers
to occur if a dock device is connected at init time (the xhci_hcd
and thunderbolt modules crash which prevents peripherals connected
through them from working).

Commit c8b1917c8987 effectively causes commit ecc1165b8b74 ("ACPICA:
Dispatch active GPEs at init time") to get undone, so the problem
addressed by commit ecc1165b8b74 appears again as a result of it.

Fixes: c8b1917c8987 ("ACPICA: Clear status of GPEs before enabling them")
Link: https://lore.kernel.org/lkml/s5hy33siofw.wl-tiwai@suse.de/T/#u
Link: https://bugzilla.opensuse.org/show_bug.cgi?id=1132943
Reported-by: Michael Hirmke &lt;opensuse@mike.franken.de&gt;
Reported-by: Takashi Iwai &lt;tiwai@suse.de&gt;
Cc: 4.17+ &lt;stable@vger.kernel.org&gt; # 4.17+
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'libnvdimm-fixes-5.1-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm</title>
<updated>2019-04-15T23:48:51+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2019-04-15T23:48:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=618d919cae2fcaadc752f27ddac8b939da8b441a'/>
<id>618d919cae2fcaadc752f27ddac8b939da8b441a</id>
<content type='text'>
Pull libnvdimm fixes from Dan Williams:
 "I debated holding this back for the v5.2 merge window due to the size
  of the "zero-key" changes, but affected users would benefit from
  having the fixes sooner. It did not make sense to change the zero-key
  semantic in isolation for the "secure-erase" command, but instead
  include it for all security commands.

  The short background on the need for these changes is that some NVDIMM
  platforms enable security with a default zero-key rather than let the
  OS specify the initial key. This makes the security enabling that
  landed in v5.0 unusable for some users.

  Summary:

   - Compatibility fix for nvdimm-security implementations with a
     default zero-key.

   - Miscellaneous small fixes for out-of-bound accesses, cleanup after
     initialization failures, and missing debug messages"

* tag 'libnvdimm-fixes-5.1-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  tools/testing/nvdimm: Retain security state after overwrite
  libnvdimm/pmem: fix a possible OOB access when read and write pmem
  libnvdimm/security, acpi/nfit: unify zero-key for all security commands
  libnvdimm/security: provide fix for secure-erase to use zero-key
  libnvdimm/btt: Fix a kmemdup failure check
  libnvdimm/namespace: Fix a potential NULL pointer dereference
  acpi/nfit: Always dump _DSM output payload
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull libnvdimm fixes from Dan Williams:
 "I debated holding this back for the v5.2 merge window due to the size
  of the "zero-key" changes, but affected users would benefit from
  having the fixes sooner. It did not make sense to change the zero-key
  semantic in isolation for the "secure-erase" command, but instead
  include it for all security commands.

  The short background on the need for these changes is that some NVDIMM
  platforms enable security with a default zero-key rather than let the
  OS specify the initial key. This makes the security enabling that
  landed in v5.0 unusable for some users.

  Summary:

   - Compatibility fix for nvdimm-security implementations with a
     default zero-key.

   - Miscellaneous small fixes for out-of-bound accesses, cleanup after
     initialization failures, and missing debug messages"

* tag 'libnvdimm-fixes-5.1-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  tools/testing/nvdimm: Retain security state after overwrite
  libnvdimm/pmem: fix a possible OOB access when read and write pmem
  libnvdimm/security, acpi/nfit: unify zero-key for all security commands
  libnvdimm/security: provide fix for secure-erase to use zero-key
  libnvdimm/btt: Fix a kmemdup failure check
  libnvdimm/namespace: Fix a potential NULL pointer dereference
  acpi/nfit: Always dump _DSM output payload
</pre>
</div>
</content>
</entry>
<entry>
<title>ACPICA: Namespace: remove address node from global list after method termination</title>
<updated>2019-04-09T08:05:11+00:00</updated>
<author>
<name>Erik Schmauss</name>
<email>erik.schmauss@intel.com</email>
</author>
<published>2019-04-08T20:42:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c5781ffbbd4f742a58263458145fe7f0ac01d9e0'/>
<id>c5781ffbbd4f742a58263458145fe7f0ac01d9e0</id>
<content type='text'>
ACPICA commit b233720031a480abd438f2e9c643080929d144c3

ASL operation_regions declare a range of addresses that it uses. In a
perfect world, the range of addresses should be used exclusively by
the AML interpreter. The OS can use this information to decide which
drivers to load so that the AML interpreter and device drivers use
different regions of memory.

During table load, the address information is added to a global
address range list. Each node in this list contains an address range
as well as a namespace node of the operation_region. This list is
deleted at ACPI shutdown.

Unfortunately, ASL operation_regions can be declared inside of control
methods. Although this is not recommended, modern firmware contains
such code. New module level code changes unintentionally removed the
functionality of adding and removing nodes to the global address
range list.

A few months ago, support for adding addresses has been re-
implemented. However, the removal of the address range list was
missed and resulted in some systems to crash due to the address list
containing bogus namespace nodes from operation_regions declared in
control methods. In order to fix the crash, this change removes
dynamic operation_regions after control method termination.

Link: https://github.com/acpica/acpica/commit/b2337200
Link: https://bugzilla.kernel.org/show_bug.cgi?id=202475
Fixes: 4abb951b73ff ("ACPICA: AML interpreter: add region addresses in global list during initialization")
Reported-by: Michael J Gruber &lt;mjg@fedoraproject.org&gt;
Signed-off-by: Erik Schmauss &lt;erik.schmauss@intel.com&gt;
Signed-off-by: Bob Moore &lt;robert.moore@intel.com&gt;
Cc: 4.20+ &lt;stable@vger.kernel.org&gt; # 4.20+
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>
ACPICA commit b233720031a480abd438f2e9c643080929d144c3

ASL operation_regions declare a range of addresses that it uses. In a
perfect world, the range of addresses should be used exclusively by
the AML interpreter. The OS can use this information to decide which
drivers to load so that the AML interpreter and device drivers use
different regions of memory.

During table load, the address information is added to a global
address range list. Each node in this list contains an address range
as well as a namespace node of the operation_region. This list is
deleted at ACPI shutdown.

Unfortunately, ASL operation_regions can be declared inside of control
methods. Although this is not recommended, modern firmware contains
such code. New module level code changes unintentionally removed the
functionality of adding and removing nodes to the global address
range list.

A few months ago, support for adding addresses has been re-
implemented. However, the removal of the address range list was
missed and resulted in some systems to crash due to the address list
containing bogus namespace nodes from operation_regions declared in
control methods. In order to fix the crash, this change removes
dynamic operation_regions after control method termination.

Link: https://github.com/acpica/acpica/commit/b2337200
Link: https://bugzilla.kernel.org/show_bug.cgi?id=202475
Fixes: 4abb951b73ff ("ACPICA: AML interpreter: add region addresses in global list during initialization")
Reported-by: Michael J Gruber &lt;mjg@fedoraproject.org&gt;
Signed-off-by: Erik Schmauss &lt;erik.schmauss@intel.com&gt;
Signed-off-by: Bob Moore &lt;robert.moore@intel.com&gt;
Cc: 4.20+ &lt;stable@vger.kernel.org&gt; # 4.20+
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'acpi-5.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm</title>
<updated>2019-04-05T00:48:11+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2019-04-05T00:48:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b512f71221d0bcb07ab32f3e958a84e164c85881'/>
<id>b512f71221d0bcb07ab32f3e958a84e164c85881</id>
<content type='text'>
Pull ACPI fix from Rafael Wysocki:
 "Prevent stale GPE events from triggering spurious system wakeups from
  suspend-to-idle (Furquan Shaikh)"

* tag 'acpi-5.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPICA: Clear status of GPEs before enabling them
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull ACPI fix from Rafael Wysocki:
 "Prevent stale GPE events from triggering spurious system wakeups from
  suspend-to-idle (Furquan Shaikh)"

* tag 'acpi-5.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPICA: Clear status of GPEs before enabling them
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'acpica' into acpi</title>
<updated>2019-04-04T20:08:47+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2019-04-04T20:08:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b59fb7ef5240c301ca8b5b70d4298c0f053bb0c3'/>
<id>b59fb7ef5240c301ca8b5b70d4298c0f053bb0c3</id>
<content type='text'>
* acpica:
  ACPICA: Clear status of GPEs before enabling them
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
* acpica:
  ACPICA: Clear status of GPEs before enabling them
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'acpi-5.1-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm</title>
<updated>2019-03-30T17:09:11+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2019-03-30T17:09:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=782492a7a4807317319a0b1832594d07ba79747d'/>
<id>782492a7a4807317319a0b1832594d07ba79747d</id>
<content type='text'>
Pull ACPI fix from Rafael Wysocki:
 "This corrects a previous attempt to make Linux use its own set of ACPI
  debug flags different from the upstream ACPICA's default (Erik
  Schmauss)"

* tag 'acpi-5.1-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI: use different default debug value than ACPICA
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull ACPI fix from Rafael Wysocki:
 "This corrects a previous attempt to make Linux use its own set of ACPI
  debug flags different from the upstream ACPICA's default (Erik
  Schmauss)"

* tag 'acpi-5.1-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI: use different default debug value than ACPICA
</pre>
</div>
</content>
</entry>
<entry>
<title>libnvdimm/security, acpi/nfit: unify zero-key for all security commands</title>
<updated>2019-03-30T15:27:07+00:00</updated>
<author>
<name>Dave Jiang</name>
<email>dave.jiang@intel.com</email>
</author>
<published>2019-03-27T18:12:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d2e5b6436c28e7ee4988497d31122e06217876fb'/>
<id>d2e5b6436c28e7ee4988497d31122e06217876fb</id>
<content type='text'>
With zero-key defined, we can remove previous detection of key id 0 or null
key in order to deal with a zero-key situation. Syncing all security
commands to use the zero-key. Helper functions are introduced to return the
data that points to the actual key payload or the zero_key. This helps
uniformly handle the key material even with zero_key.

Signed-off-by: Dave Jiang &lt;dave.jiang@intel.com&gt;
Signed-off-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
With zero-key defined, we can remove previous detection of key id 0 or null
key in order to deal with a zero-key situation. Syncing all security
commands to use the zero-key. Helper functions are introduced to return the
data that points to the actual key payload or the zero_key. This helps
uniformly handle the key material even with zero_key.

Signed-off-by: Dave Jiang &lt;dave.jiang@intel.com&gt;
Signed-off-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ACPICA: Clear status of GPEs before enabling them</title>
<updated>2019-03-28T09:27:02+00:00</updated>
<author>
<name>Furquan Shaikh</name>
<email>furquan@google.com</email>
</author>
<published>2019-03-20T22:28:44+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c8b1917c8987a6fa3695d479b4d60fbbbc3e537b'/>
<id>c8b1917c8987a6fa3695d479b4d60fbbbc3e537b</id>
<content type='text'>
Commit 18996f2db918 ("ACPICA: Events: Stop unconditionally clearing
ACPI IRQs during suspend/resume") was added to stop clearing event
status bits unconditionally in the system-wide suspend and resume
paths. This was done because of an issue with a laptop lid appaering
to be closed even when it was used to wake up the system from suspend
(see https://bugzilla.kernel.org/show_bug.cgi?id=196249), which
happened because event status bits were cleared unconditionally on
system resume. Though this change fixed the issue in the resume path,
it introduced regressions in a few suspend paths.

First regression was reported and fixed in the S5 entry path by commit
fa85015c0d95 ("ACPICA: Clear status of all events when entering S5").
Next regression was reported and fixed for all legacy sleep paths by
commit f317c7dc12b7 ("ACPICA: Clear status of all events when entering
sleep states").  However, there still is a suspend-to-idle regression,
since suspend-to-idle does not follow the legacy sleep paths.

In the suspend-to-idle case, wakeup is enabled as part of device
suspend.  If the status bits of wakeup GPEs are set when they are
enabled, it causes a premature system wakeup to occur.

To address that problem, partially revert commit 18996f2db918 to
restore GPE status bits clearing before the GPE is enabled in
acpi_ev_enable_gpe().

Fixes: 18996f2db918 ("ACPICA: Events: Stop unconditionally clearing ACPI IRQs during suspend/resume")
Signed-off-by: Furquan Shaikh &lt;furquan@google.com&gt;
Cc: 4.17+ &lt;stable@vger.kernel.org&gt; # 4.17+
[ rjw: Subject &amp; changelog ]
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>
Commit 18996f2db918 ("ACPICA: Events: Stop unconditionally clearing
ACPI IRQs during suspend/resume") was added to stop clearing event
status bits unconditionally in the system-wide suspend and resume
paths. This was done because of an issue with a laptop lid appaering
to be closed even when it was used to wake up the system from suspend
(see https://bugzilla.kernel.org/show_bug.cgi?id=196249), which
happened because event status bits were cleared unconditionally on
system resume. Though this change fixed the issue in the resume path,
it introduced regressions in a few suspend paths.

First regression was reported and fixed in the S5 entry path by commit
fa85015c0d95 ("ACPICA: Clear status of all events when entering S5").
Next regression was reported and fixed for all legacy sleep paths by
commit f317c7dc12b7 ("ACPICA: Clear status of all events when entering
sleep states").  However, there still is a suspend-to-idle regression,
since suspend-to-idle does not follow the legacy sleep paths.

In the suspend-to-idle case, wakeup is enabled as part of device
suspend.  If the status bits of wakeup GPEs are set when they are
enabled, it causes a premature system wakeup to occur.

To address that problem, partially revert commit 18996f2db918 to
restore GPE status bits clearing before the GPE is enabled in
acpi_ev_enable_gpe().

Fixes: 18996f2db918 ("ACPICA: Events: Stop unconditionally clearing ACPI IRQs during suspend/resume")
Signed-off-by: Furquan Shaikh &lt;furquan@google.com&gt;
Cc: 4.17+ &lt;stable@vger.kernel.org&gt; # 4.17+
[ rjw: Subject &amp; changelog ]
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ACPI / CPPC: Fix guaranteed performance handling</title>
<updated>2019-03-25T22:57:21+00:00</updated>
<author>
<name>Srinivas Pandruvada</name>
<email>srinivas.pandruvada@linux.intel.com</email>
</author>
<published>2019-03-25T16:04:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=edef1ef134180149694b86386277076f566d165c'/>
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As per the ACPI specification, "Guaranteed Performance Register" is
a "Buffer" field and it cannot be "Integer", so treat the "Integer"
type for "Guaranteed Performance Register" field as invalid and
ignore its value in that case.

Also save one cpc_read() call when "Guaranteed Performance Register"
is not present, which means a register defined as:
"Register(SystemMemory, 0, 0, 0, 0)".

Fixes: 29523f095397 ("ACPI / CPPC: Add support for guaranteed performance")
Suggested-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Srinivas Pandruvada &lt;srinivas.pandruvada@linux.intel.com&gt;
Cc: 4.20+ &lt;stable@vger.kernel.org&gt; # 4.20+
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
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As per the ACPI specification, "Guaranteed Performance Register" is
a "Buffer" field and it cannot be "Integer", so treat the "Integer"
type for "Guaranteed Performance Register" field as invalid and
ignore its value in that case.

Also save one cpc_read() call when "Guaranteed Performance Register"
is not present, which means a register defined as:
"Register(SystemMemory, 0, 0, 0, 0)".

Fixes: 29523f095397 ("ACPI / CPPC: Add support for guaranteed performance")
Suggested-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Srinivas Pandruvada &lt;srinivas.pandruvada@linux.intel.com&gt;
Cc: 4.20+ &lt;stable@vger.kernel.org&gt; # 4.20+
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
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