Commit Graph

33 Commits

Author SHA1 Message Date
Viresh Kumar 2c2709dc69 PM / OPP: Rename structures for clarity
Stephen pointed out recently, that few structures always confuse him as
they aren't named properly. And this patch tries to address that:

Names are updated as:
- device_opp or dev_opp -> opp_table
- dev_opp_list -> opp_tables
- dev_opp_list_lock -> opp_table_lock
- device_list_opp -> opp_device (it was never a list, but a structure)
- list_dev -> opp_dev
- And similar changes in comments and function names as well.

This also fixes checkpatch warnings that were generated with this patch.

No functional changes.

Suggested-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-02-21 14:24:35 +01:00
Viresh Kumar a5da64477e PM / OPP: Fix incorrect comments
Some comments were just copy/pasted from other sections and don't match
to the routines they were added for. Fix them.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-02-21 14:24:04 +01:00
Viresh Kumar 0c717d0f9c PM / OPP: Initialize regulator pointer to an error value
We are currently required to do two checks for regulator pointer:
IS_ERR() and IS_NULL().

And multiple instances are reported, about both of these not being used
consistently and so resulting in crashes.

Fix that by initializing regulator pointer with an error value and
checking it only against an error.

This makes code more consistent and more efficient.

Fixes: 7d34d56ef3 (PM / OPP: Disable OPPs that aren't supported by the regulator)
Reported-and-tested-by: Jon Hunter <jonathanh@nvidia.com>
Reported-and-tested-by: Tony Lindgren <tony@atomide.com>
Reported-and-tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[ rjw: Initialize to -ENXIO ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-02-16 13:12:41 +01:00
Viresh Kumar c88c395f4a PM / OPP: Initialize u_volt_min/max to a valid value
We kept u_volt_min/max initialized to 0, when only the target voltage is
present in DT, instead of the target/min/max triplet.

This didn't go well with the regulator framework, as on few calls the
min voltage was set to target and max was set to 0 and so resulted in a
kernel crash like below:

kernel BUG at ../drivers/regulator/core.c:216!

[<c0684af4>] (regulator_check_voltage) from [<c06857ac>] (regulator_set_voltage_unlocked+0x58/0x230)
[<c06857ac>] (regulator_set_voltage_unlocked) from [<c06859ac>] (regulator_set_voltage+0x28/0x54)
[<c06859ac>] (regulator_set_voltage) from [<c0775b28>] (_set_opp_voltage+0x30/0x98)
[<c0775b28>] (_set_opp_voltage) from [<c0776630>] (dev_pm_opp_set_rate+0xf0/0x28c)
[<c0776630>] (dev_pm_opp_set_rate) from [<c096f784>] (__cpufreq_driver_target+0x184/0x2b4)
[<c096f784>] (__cpufreq_driver_target) from [<c0973760>] (dbs_check_cpu+0x1b0/0x1f4)
[<c0973760>] (dbs_check_cpu) from [<c0973f30>] (cpufreq_governor_dbs+0x324/0x5c4)
[<c0973f30>] (cpufreq_governor_dbs) from [<c0970958>] (__cpufreq_governor+0xe4/0x1ec)
[<c0970958>] (__cpufreq_governor) from [<c09711e0>] (cpufreq_init_policy+0x64/0x8c)
[<c09711e0>] (cpufreq_init_policy) from [<c09718cc>] (cpufreq_online+0x2fc/0x708)
[<c09718cc>] (cpufreq_online) from [<c0765ff0>] (subsys_interface_register+0x94/0xd8)
[<c0765ff0>] (subsys_interface_register) from [<c0970530>] (cpufreq_register_driver+0x14c/0x19c)
[<c0970530>] (cpufreq_register_driver) from [<c09746dc>] (dt_cpufreq_probe+0x70/0xec)
[<c09746dc>] (dt_cpufreq_probe) from [<c076907c>] (platform_drv_probe+0x4c/0xb0)
[<c076907c>] (platform_drv_probe) from [<c07678e0>] (driver_probe_device+0x214/0x2c0)
[<c07678e0>] (driver_probe_device) from [<c0767a18>] (__driver_attach+0x8c/0x90)
[<c0767a18>] (__driver_attach) from [<c0765c2c>] (bus_for_each_dev+0x68/0x9c)
[<c0765c2c>] (bus_for_each_dev) from [<c0766d78>] (bus_add_driver+0x1a0/0x218)
[<c0766d78>] (bus_add_driver) from [<c076810c>] (driver_register+0x78/0xf8)
[<c076810c>] (driver_register) from [<c0301d74>] (do_one_initcall+0x90/0x1d8)
[<c0301d74>] (do_one_initcall) from [<c1100e14>] (kernel_init_freeable+0x15c/0x1fc)
[<c1100e14>] (kernel_init_freeable) from [<c0b27a0c>] (kernel_init+0x8/0xf0)
[<c0b27a0c>] (kernel_init) from [<c0307d78>] (ret_from_fork+0x14/0x3c)
Code: e1550004 baffffeb e3a00000 e8bd8070 (e7f001f2)

Fix that by initializing u_volt_min/max to the target voltage in such cases.

Reported-and-tested-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Fixes: 274659029c (PM / OPP: Add support to parse "operating-points-v2" bindings)
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-02-15 22:55:35 +01:00
Jon Hunter 78ecc56247 PM / OPP: Fix NULL pointer dereference crash when disabling OPPs
Commit 7d34d56ef3 (PM / OPP: Disable OPPs that aren't supported by
the regulator) causes a crash to happen on Tegra124 Jetson TK1 when
using the DFLL clock source for the CPU.  The DFLL manages the voltage
itself and so there is no regulator specified for the OPPs and so we
get a crash when we try to dereference the regulator pointer.  Fix
this by checking to see if the regulator IS_ERR_OR_NULL before
dereferencing it.

Fixes: 7d34d56ef3 (PM / OPP: Disable OPPs that aren't supported by the regulator)
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Reported-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
[ rjw: Changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-02-11 22:05:38 +01:00
Viresh Kumar 6a0712f6f1 PM / OPP: Add dev_pm_opp_set_rate()
This adds a routine, dev_pm_opp_set_rate(), responsible for configuring
power-supply and clock source for an OPP.

The OPP is found by matching against the target_freq passed to the
routine. This shall replace similar code present in most of the OPP
users and help simplify them a lot.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-02-10 01:11:54 +01:00
Viresh Kumar d54974c251 PM / OPP: Manage device clk
OPP core has got almost everything now to manage device's OPP
transitions, the only thing left is device's clk. Get that as well.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-02-10 01:11:54 +01:00
Viresh Kumar 50f8cfbd58 PM / OPP: Parse clock-latency and voltage-tolerance for v1 bindings
V2 bindings have better support for clock-latency and voltage-tolerance
and doesn't need special care. To use callbacks, like
dev_pm_opp_get_max_{transition|volt}_latency(), irrespective of the
bindings, the core needs to know clock-latency/voltage-tolerance for the
earlier bindings.

This patch reads clock-latency/voltage-tolerance from the device node,
irrespective of the bindings (to keep it simple) and use them only for
V1 bindings.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-02-10 01:11:54 +01:00
Viresh Kumar 2174344765 PM / OPP: Introduce dev_pm_opp_get_max_transition_latency()
In few use cases (like: cpufreq), it is desired to get the maximum
latency for changing OPPs. Add support for that.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-02-10 01:11:53 +01:00
Viresh Kumar 655c9df961 PM / OPP: Introduce dev_pm_opp_get_max_volt_latency()
In few use cases (like: cpufreq), it is desired to get the maximum
voltage latency for changing OPPs. Add support for that.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-02-10 01:11:53 +01:00
Viresh Kumar 7d34d56ef3 PM / OPP: Disable OPPs that aren't supported by the regulator
Disable any OPPs where the connected regulator isn't able to provide the
specified voltage.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-02-10 01:11:53 +01:00
Viresh Kumar 9f8ea969d5 PM / OPP: get/put regulators from OPP core
This allows the OPP core to request/free the regulator resource,
attached to a device OPP. The regulator device is fetched using the name
provided by the driver, while calling: dev_pm_opp_set_regulator().

This will work for both OPP-v1 and v2 bindings.

This is a preliminary step for moving the OPP switching logic into the
OPP core.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-02-10 01:11:53 +01:00
Viresh Kumar 5ff24d6010 PM / OPP: Use snprintf() instead of sprintf()
sprintf() can access memory outside of the range of the character array,
and is risky in some situations. The driver specified prop_name string
can be longer than NAME_MAX here (only an attacker will do that though)
and so blindly copying it into the character array of size NAME_MAX
isn't safe. Instead we must use snprintf() here.

Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-01-06 02:38:27 +01:00
Pi-Cheng Chen d9de19b1cc PM / OPP: Set cpu_dev->id in cpumask first
Set cpu_dev->id in cpumask first when setting up cpumask for CPUs that
share the same OPP table. This might be helpful when handling cpumask
without the original CPU bitfield set.

Signed-off-by: Pi-Cheng Chen <pi-cheng.chen@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-01-02 00:48:11 +01:00
Bartlomiej Zolnierkiewicz fd8d8e6346 PM / OPP: Fix parsing of opp-microvolt and opp-microamp properties
Commit 01fb4d3c39 ("PM / OPP: Parse 'opp-<prop>-<name>'
bindings") broke support for parsing standard opp-microvolt and
opp-microamp properties.  Fix it by setting 'name' string to
proper value for !prop cases.

Fixes: 01fb4d3c39 ("PM / OPP: Parse 'opp-<prop>-<name> 'bindings")
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-12-28 01:48:21 +01:00
Viresh Kumar 01fb4d3c39 PM / OPP: Parse 'opp-<prop>-<name>' bindings
OPP bindings (for few properties) allow a platform to choose a
value/range among a set of available options. The options are present as
opp-<prop>-<name>, where the platform needs to supply the <name> string.

The OPP properties which allow such an option are: opp-microvolt and
opp-microamp.

Add support to the OPP-core to parse these bindings, by introducing
dev_pm_opp_{set|put}_prop_name() APIs.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-12-10 23:08:51 +01:00
Viresh Kumar 7de36b0aa5 PM / OPP: Parse 'opp-supported-hw' binding
OPP bindings allow a platform to enable OPPs based on the version of the
hardware they are used for.

Add support to the OPP-core to parse these bindings, by introducing
dev_pm_opp_{set|put}_supported_hw() APIs.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-12-10 23:08:51 +01:00
Viresh Kumar dc4e7b1fa2 PM / OPP: Add missing doc comments
Few doc-style comments were missing, add them. Rearrange another one to
match the sequence within the structure.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-11-23 23:42:40 +01:00
Viresh Kumar deaa514651 PM / OPP: Add debugfs support
This patch adds debugfs support to OPP layer to export OPPs and their
properties for all the devices.

This creates a top level directory: /sys/kernel/debug/opp and then
device specific directories (based on device names) inside it. For
example: 'cpu0', 'cpu1', etc..

If multiple devices share the OPP table, then the real directory is
created only for the first device. For all others, links are created to
the real directory.

Inside the device specific directory, a separate directory is created
for each OPP. And within that files per opp property.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-11-23 23:38:23 +01:00
Linus Torvalds be23c9d20b More power management and ACPI updates for v4.4-rc1
- Support for the ACPI _CCA configuration object intended to tell
    the OS whether or not a bus master device supports hardware
    managed cache coherency and a new set of functions to allow
    drivers to check the cache coherency support for devices in a
    platform firmware interface agnostic way (Suravee Suthikulpanit,
    Jeremy Linton).
 
  - ACPI backlight quirks for ESPRIMO Mobile M9410 and Dell XPS L421X
    (Aaron Lu, Hans de Goede).
 
  - Fixes for the arm_big_little and s5pv210-cpufreq cpufreq drivers
    (Jon Medhurst, Nicolas Pitre).
 
  - kfree()-related fixup for the recently introduced CPPC cpufreq
    frontend (Markus Elfring).
 
  - intel_pstate fix reducing kernel log noise on systems where
    P-states are managed by hardware (Prarit Bhargava).
 
  - intel_pstate maintainers information update (Srinivas Pandruvada).
 
  - cpufreq core optimization related to the handling of delayed work
    items used by governors (Viresh Kumar).
 
  - Locking fixes and cleanups of the Operating Performance Points
    (OPP) framework (Viresh Kumar).
 
  - Generic power domains framework cleanups (Lina Iyer).
 
  - cpupower tool updates (Jacob Tanenbaum, Sriram Raghunathan,
    Thomas Renninger).
 
  - turbostat tool updates (Len Brown).
 
 /
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Merge tag 'pm+acpi-4.4-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull more power management and ACPI updates from Rafael Wysocki:
 "The only new feature in this batch is support for the ACPI _CCA device
  configuration object, which it a pre-requisite for future ACPI PCI
  support on ARM64, but should not affect the other architectures.

  The rest is fixes and cleanups, mostly in cpufreq (including
  intel_pstate), the Operating Performace Points (OPP) framework and
  tools (cpupower and turbostat).

  Specifics:

   - Support for the ACPI _CCA configuration object intended to tell the
     OS whether or not a bus master device supports hardware managed
     cache coherency and a new set of functions to allow drivers to
     check the cache coherency support for devices in a platform
     firmware interface agnostic way (Suravee Suthikulpanit, Jeremy
     Linton).

   - ACPI backlight quirks for ESPRIMO Mobile M9410 and Dell XPS L421X
     (Aaron Lu, Hans de Goede).

   - Fixes for the arm_big_little and s5pv210-cpufreq cpufreq drivers
     (Jon Medhurst, Nicolas Pitre).

   - kfree()-related fixup for the recently introduced CPPC cpufreq
     frontend (Markus Elfring).

   - intel_pstate fix reducing kernel log noise on systems where
     P-states are managed by hardware (Prarit Bhargava).

   - intel_pstate maintainers information update (Srinivas Pandruvada).

   - cpufreq core optimization related to the handling of delayed work
     items used by governors (Viresh Kumar).

   - Locking fixes and cleanups of the Operating Performance Points
     (OPP) framework (Viresh Kumar).

   - Generic power domains framework cleanups (Lina Iyer).

   - cpupower tool updates (Jacob Tanenbaum, Sriram Raghunathan, Thomas
     Renninger).

   - turbostat tool updates (Len Brown)"

* tag 'pm+acpi-4.4-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (32 commits)
  PCI: ACPI: Add support for PCI device DMA coherency
  PCI: OF: Move of_pci_dma_configure() to pci_dma_configure()
  of/pci: Fix pci_get_host_bridge_device leak
  device property: ACPI: Remove unused DMA APIs
  device property: ACPI: Make use of the new DMA Attribute APIs
  device property: Adding DMA Attribute APIs for Generic Devices
  ACPI: Adding DMA Attribute APIs for ACPI Device
  device property: Introducing enum dev_dma_attr
  ACPI: Honor ACPI _CCA attribute setting
  cpufreq: CPPC: Delete an unnecessary check before the function call kfree()
  PM / OPP: Add opp_rcu_lockdep_assert() to _find_device_opp()
  PM / OPP: Hold dev_opp_list_lock for writers
  PM / OPP: Protect updates to list_dev with mutex
  PM / OPP: Propagate error properly from dev_pm_opp_set_sharing_cpus()
  cpufreq: s5pv210-cpufreq: fix wrong do_div() usage
  MAINTAINERS: update for intel P-state driver
  Creating a common structure initialization pattern for struct option
  cpupower: Enable disabled Cstates if they are below max latency
  cpupower: Remove debug message when using cpupower idle-set -D switch
  cpupower: cpupower monitor reports uninitialized values for offline cpus
  ...
2015-11-12 11:50:33 -08:00
Linus Torvalds baf51c4392 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux
Pull thermal updates from Zhang Rui:

 - Implement generic devfreq cooling mechanism through frequency
   reduction for devices using devfreq.  From Ørjan Eide and Javi
   Merino.

 - Introduce OMAP3 support on TI SoC thermal driver.  From Pavel Mack
   and Eduardo Valentin.

 - A bounch of small fixes on devfreq_cooling, Exynos, IMX, Armada, and
   Rockchip thermal drivers.

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux: (24 commits)
  thermal: exynos: Directly return 0 instead of using local ret variable
  thermal: exynos: Remove unneeded semicolon
  thermal: exynos: Use IS_ERR() because regulator cannot be NULL
  thermal: exynos: Fix first temperature read after registering sensor
  thermal: exynos: Fix unbalanced regulator disable on probe failure
  devfreq_cooling: return on allocation failure
  thermal: rockchip: support the sleep pinctrl state to avoid glitches in s2r
  dt-bindings: rockchip-thermal: Add the pinctrl states in this document
  thermal: devfreq_cooling: Make power a u64
  thermal: devfreq_cooling: use a thermal_cooling_device for register and unregister
  thermal: underflow bug in imx_set_trip_temp()
  thermal: armada: Fix possible overflow in the Armada 380 thermal sensor formula
  thermal: imx: register irq handler later in probe
  thermal: rockhip: fix setting thermal shutdown polarity
  thermal: rockchip: fix handling of invalid readings
  devfreq_cooling: add trace information
  thermal: Add devfreq cooling
  PM / OPP: get the voltage for all OPPs
  tools/thermal: tmon: use pkg-config also for CFLAGS
  linux/thermal.h: rename KELVIN_TO_CELSIUS to DECI_KELVIN_TO_CELSIUS
  ...
2015-11-11 09:03:01 -08:00
Rafael J. Wysocki 1ede53f731 Merge branch 'pm-opp'
* pm-opp:
  PM / OPP: Add opp_rcu_lockdep_assert() to _find_device_opp()
  PM / OPP: Hold dev_opp_list_lock for writers
  PM / OPP: Protect updates to list_dev with mutex
  PM / OPP: Propagate error properly from dev_pm_opp_set_sharing_cpus()
  PM / OPP: Parse all power-supply related bindings together
  PM / OPP: Rename routines specific to old bindings with _v1
  PM / OPP: Improve print messages with pr_fmt
2015-11-07 01:30:40 +01:00
Viresh Kumar 0597e81850 PM / OPP: Add opp_rcu_lockdep_assert() to _find_device_opp()
_find_device_opp() should be called with rcu-read lock or
dev_opp_list_lock held. Add the opp_rcu_lockdep_assert() check to make
sure caller have taken appropriate locks.

Fix comment over the routine as well.

Suggested-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-11-06 23:59:42 +01:00
Viresh Kumar 4a3a1353a8 PM / OPP: Hold dev_opp_list_lock for writers
Writers need to update OPP device and their list with dev_opp_list_lock
mutex held, which was missed at few places. Fix it.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: 4.3 <stable@vger.kernel.org> # 4.3
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-11-06 23:59:41 +01:00
Viresh Kumar 87b4115db0 PM / OPP: Protect updates to list_dev with mutex
dev_opp_list_lock is used everywhere to protect device and OPP lists,
but dev_pm_opp_set_sharing_cpus() is missed somehow. And instead we used
rcu-lock, which wouldn't help here as we are adding a new list_dev.

This also fixes a problem where we have called kzalloc(..., GFP_KERNEL)
from within rcu-lock, which isn't allowed as kzalloc can sleep when
called with GFP_KERNEL.

With CONFIG_DEBUG_ATOMIC_SLEEP set, we get following lockdep-splat:

include/linux/rcupdate.h:578 Illegal context switch in RCU read-side critical section!

other info that might help us debug this:

rcu_scheduler_active = 1, debug_locks = 0
5 locks held by swapper/0/1:
 #0:  (&dev->mutex){......}, at: [<c02f68f4>] __driver_attach+0x48/0x98
 #1:  (&dev->mutex){......}, at: [<c02f6904>] __driver_attach+0x58/0x98
 #2:  (cpu_hotplug.lock){++++++}, at: [<c00249d0>] get_online_cpus+0x40/0xb0
 #3:  (subsys mutex#5){+.+.+.}, at: [<c02f4f8c>] subsys_interface_register+0x44/0xdc
 #4:  (rcu_read_lock){......}, at: [<c0305c80>] dev_pm_opp_set_sharing_cpus+0x0/0x1e4

stack backtrace:
CPU: 1 PID: 1 Comm: swapper/0 Tainted: G        W       4.3.0-rc7-00047-g81f5932958a8 #59
Hardware name: SAMSUNG EXYNOS (Flattened Device Tree)
[<c0016874>] (unwind_backtrace) from [<c001355c>] (show_stack+0x10/0x14)
[<c001355c>] (show_stack) from [<c022553c>] (dump_stack+0x94/0xbc)
[<c022553c>] (dump_stack) from [<c004904c>] (___might_sleep+0x24c/0x298)
[<c004904c>] (___might_sleep) from [<c00f07e4>] (kmem_cache_alloc+0xe8/0x164)
[<c00f07e4>] (kmem_cache_alloc) from [<c0305354>] (_add_list_dev+0x30/0x58)
[<c0305354>] (_add_list_dev) from [<c0305d50>] (dev_pm_opp_set_sharing_cpus+0xd0/0x1e4)
[<c0305d50>] (dev_pm_opp_set_sharing_cpus) from [<c040eda4>] (cpufreq_init+0x4cc/0x62c)
[<c040eda4>] (cpufreq_init) from [<c040a964>] (cpufreq_online+0xbc/0x73c)
[<c040a964>] (cpufreq_online) from [<c02f4fe0>] (subsys_interface_register+0x98/0xdc)
[<c02f4fe0>] (subsys_interface_register) from [<c040a640>] (cpufreq_register_driver+0x110/0x17c)
[<c040a640>] (cpufreq_register_driver) from [<c040ef64>] (dt_cpufreq_probe+0x60/0x8c)
[<c040ef64>] (dt_cpufreq_probe) from [<c02f8084>] (platform_drv_probe+0x44/0xa4)
[<c02f8084>] (platform_drv_probe) from [<c02f67c0>] (driver_probe_device+0x208/0x2f4)
[<c02f67c0>] (driver_probe_device) from [<c02f6940>] (__driver_attach+0x94/0x98)
[<c02f6940>] (__driver_attach) from [<c02f4c1c>] (bus_for_each_dev+0x68/0x9c)

Reported-by: Michael Turquette <mturquette@baylibre.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: 4.3 <stable@vger.kernel.org> # 4.3
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-11-06 23:59:41 +01:00
Viresh Kumar 1794ec1f95 PM / OPP: Propagate error properly from dev_pm_opp_set_sharing_cpus()
We are returning 0 even in case of errors, fix it.

Fixes: 8d4d4e98ac ("PM / OPP: Add helpers for initializing CPU OPPs")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: 4.3 <stable@vger.kernel.org> # 4.3
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-11-06 23:59:41 +01:00
Viresh Kumar ad623c3148 PM / OPP: Parse all power-supply related bindings together
Move all DT parsing for the power supplies to a single function, rather
than keeping them at separate places. This will help manage things
properly.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-11-02 01:51:23 +01:00
Viresh Kumar b64b9c3f90 PM / OPP: Rename routines specific to old bindings with _v1
Clearly distinguish routines based on what version of bindings they
parse. We have already postfixed routines properly with _v2 for new
bindings. Postfix the older ones now with _v1.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-11-02 01:48:48 +01:00
Viresh Kumar d6d2a5289a PM / OPP: Improve print messages with pr_fmt
To identify OPP core's print messages easily, prefix them with
KBUILD_MODNAME.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-11-02 01:47:43 +01:00
Rafael J. Wysocki 394f7164e6 Merge branch 'pm-opp'
* pm-opp:
  PM / OPP: passing NULL to PTR_ERR()
  PM / OPP: Move cpu specific code to opp/cpu.c
  PM / OPP: Move opp core to its own directory
  PM / OPP: Prefix exported opp routines with dev_pm_opp_
  PM / OPP: Rename opp init/free table routines
  PM / OPP: reuse of_parse_phandle()
2015-11-02 00:54:37 +01:00
Dan Carpenter a6eed752f5 PM / OPP: passing NULL to PTR_ERR()
The code was using PTR_ERR(NULL) which causes a static checker warning.
I have fixed up the printks and changed the return to -ENOENT.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-10-09 22:17:34 +02:00
Viresh Kumar f59d3ee848 PM / OPP: Move cpu specific code to opp/cpu.c
Move cpu device specific code out of generic opp library, and add it to
cpu.c.

Along with that, create a core-internal opp.h header, which will be used
to share structures and function prototypes within opp core.

Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-09-15 02:03:16 +02:00
Viresh Kumar 33692dc381 PM / OPP: Move opp core to its own directory
OPP code is expanding and is already present in multiple directories
(cpufreq and power). Lets move it to its own directory, to manage it
better.

This also moves/renames the cpufreq_opp file to cpu.c, as it will
contain helpers for cpu device. Its not just about cpufreq, other
frameworks can use OPPs as well.

Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-09-15 02:03:16 +02:00