linux-stable.git/drivers/base/power, branch v4.14.45

PM / wakeirq: Fix unbalanced IRQ enable for wakeirq

2018-04-26T09:02:20+00:00

[ Upstream commit 69728051f5bf15efaf6edfbcfe1b5a49a2437918 ]

If a device is runtime PM suspended when we enter suspend and has
a dedicated wake IRQ, we can get the following warning:

WARNING: CPU: 0 PID: 108 at kernel/irq/manage.c:526 enable_irq+0x40/0x94
[  102.087860] Unbalanced enable for IRQ 147
...
(enable_irq) from [] (dev_pm_arm_wake_irq+0x4c/0x60)
(dev_pm_arm_wake_irq) from []
 (device_wakeup_arm_wake_irqs+0x58/0x9c)
(device_wakeup_arm_wake_irqs) from []
(dpm_suspend_noirq+0x10/0x48)
(dpm_suspend_noirq) from []
(suspend_devices_and_enter+0x30c/0xf14)
(suspend_devices_and_enter) from []
(enter_state+0xad4/0xbd8)
(enter_state) from [] (pm_suspend+0x38/0x98)
(pm_suspend) from [] (state_store+0x68/0xc8)

This is because the dedicated wake IRQ for the device may have been
already enabled earlier by dev_pm_enable_wake_irq_check().  Fix the
issue by checking for runtime PM suspended status.

This issue can be easily reproduced by setting serial console log level
to zero, letting the serial console idle, and suspend the system from
an ssh terminal.  On resume, dmesg will have the warning above.

The reason why I have not run into this issue earlier has been that I
typically run my PM test cases from on a serial console instead over ssh.

Fixes: c84345597558 (PM / wakeirq: Enable dedicated wakeirq for suspend)
Signed-off-by: Tony Lindgren 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

PM / domains: Fix up domain-idle-states OF parsing

2018-04-26T09:02:18+00:00

[ Upstream commit a3381e3a65cbaf612c8f584906c4dba27e84267c ]

Commit b539cc82d493 (PM / Domains: Ignore domain-idle-states that are
not compatible), made it possible to ignore non-compatible
domain-idle-states OF nodes. However, in case that happens while doing
the OF parsing, the number of elements in the allocated array would
exceed the numbers actually needed, thus wasting memory.

Fix this by pre-iterating the genpd OF node and counting the number of
compatible domain-idle-states nodes, before doing the allocation. While
doing this, it makes sense to rework the code a bit to avoid open coding,
of parts responsible for the OF node iteration.

Let's also take the opportunity to clarify the function header for
of_genpd_parse_idle_states(), about what is being returned in case of
errors.

Fixes: b539cc82d493 (PM / Domains: Ignore domain-idle-states that are not compatible)
Signed-off-by: Ulf Hansson 
Reviewed-by: Lina Iyer 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

PM / runtime: Fix handling of suppliers with disabled runtime PM

2018-02-25T10:07:58+00:00

[ Upstream commit 31eb7431805493e10f4731f366cf4d4e3e952035 ]

Prevent rpm_get_suppliers() from returning an error code if runtime
PM is disabled for one or more of the supplier devices it wants to
runtime-resume, so as to make runtime PM work for devices with links
to suppliers that don't use runtime PM (such links may be created
during device enumeration even before it is known whether or not
runtime PM will be enabled for the devices in question, for example).

Fixes: 21d5c57b3726 (PM / runtime: Use device links)
Reported-by: Adrian Hunter 
Signed-off-by: Rafael J. Wysocki 
Reviewed-by: Lukas Wunner 
Tested-by: Adrian Hunter 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

PM / OPP: Move error message to debug level

2017-12-25T13:26:26+00:00

[ Upstream commit 035ed07208dc501d023873447113f3f178592156 ]

On some i.MX6 platforms which do not have speed grading
check, opp table will not be created in platform code,
so cpufreq driver prints the following error message:

cpu cpu0: dev_pm_opp_get_opp_count: OPP table not found (-19)

However, this is not really an error in this case because the
imx6q-cpufreq driver first calls dev_pm_opp_get_opp_count()
and if it fails, it means that platform code does not provide
OPP and then dev_pm_opp_of_add_table() will be called.

In order to avoid such confusing error message, move it to
debug level.

It is up to the caller of dev_pm_opp_get_opp_count() to check its
return value and decide if it will print an error or not.

Signed-off-by: Fabio Estevam 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

PM / Domains: Fix genpd to deal with drivers returning 1 from ->prepare()

2017-12-10T12:40:38+00:00

[ Upstream commit 5241ab40f6e742f8a1631f8826faf6dc6412b3b5 ]

During system-wide PM, genpd relies on its PM callbacks to be invoked for
all its attached devices, as to deal with powering off/on the PM domain. In
other words, genpd is not compatible with the direct_complete path, if
executed by the PM core for any of its attached devices.

However, when genpd's ->prepare() callback invokes pm_generic_prepare(), it
does not take into account that it may return 1. Instead it treats that as
an error internally and expects the PM core to abort the prepare phase and
roll back. This leads to genpd not properly powering on/off the PM domain,
because its internal counters gets wrongly balanced.

To fix the behaviour, allow drivers to return 1 from their ->prepare()
callbacks, but let's return 0 from genpd's ->prepare() callback in such
case, as that prevents the PM core from running the direct_complete path
for the device.

Signed-off-by: Ulf Hansson 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

PM / OPP: Add missing of_node_put(np)

2017-11-30T08:40:41+00:00

commit 7978db344719dab1e56d05e6fc04aaaddcde0a5e upstream.

The for_each_available_child_of_node() loop in _of_add_opp_table_v2()
doesn't drop the reference to "np" on errors. Fix that.

Fixes: 274659029c9d (PM / OPP: Add support to parse "operating-points-v2" bindings)
Signed-off-by: Tobias Jordan 
[ VK: Improved commit log. ]
Signed-off-by: Viresh Kumar 
Reviewed-by: Stephen Boyd 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02T10:10:55+00:00

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart 
Reviewed-by: Philippe Ombredanne 
Reviewed-by: Thomas Gleixner 
Signed-off-by: Greg Kroah-Hartman

PM / OPP: Call notifier without holding opp_table->lock

2017-09-25T22:44:32+00:00

The notifier callbacks may want to call some OPP helper routines which
may try to take the same opp_table->lock again and cause a deadlock. One
such usecase was reported by Chanwoo Choi, where calling
dev_pm_opp_disable() leads us to the devfreq's OPP notifier handler,
which further calls dev_pm_opp_find_freq_floor() and it deadlocks.

We don't really need the opp_table->lock to be held across the notifier
call though, all we want to make sure is that the 'opp' doesn't get
freed while being used from within the notifier chain. We can do it with
help of dev_pm_opp_get/put() as well. Let's do it.

Cc: 4.11+  # 4.11+
Fixes: 5b650b388844 "PM / OPP: Take kref from _find_opp_table()"
Reported-by: Chanwoo Choi 
Tested-by: Chanwoo Choi 
Reviewed-by: Stephen Boyd 
Reviewed-by: Chanwoo Choi 
Signed-off-by: Viresh Kumar 
Signed-off-by: Rafael J. Wysocki

Merge branches 'pm-core', 'pm-qos' and 'pm-docs'

2017-09-22T20:45:28+00:00

* pm-core:
  PM: core: Fix device_pm_check_callbacks()

* pm-qos:
  PM / QoS: Use the correct variable to check the QoS request type

* pm-docs:
  PM: docs: Drop an excess character from devices.rst
  driver core: Fix link to device power management documentation

PM: core: Fix device_pm_check_callbacks()

2017-09-19T20:58:27+00:00

The device_pm_check_callbacks() function doesn't check legacy
->suspend and ->resume callback pointers under the device's
bus type, class and driver, so in some cases it may set the
no_pm_callbacks flag for the device incorrectly and then the
callbacks may be skipped during system suspend/resume, which
shouldn't happen.

Fixes: aa8e54b55947 (PM / sleep: Go direct_complete if driver has no callbacks)
Signed-off-by: Rafael J. Wysocki 
Cc: 4.5+  # 4.5+