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Merge tag 'pm+acpi-for-3.8-rc1' of git://git.kernel.org/pub/scm/linux…
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…/kernel/git/rafael/linux-pm

Pull ACPI and power management updates from Rafael Wysocki:

 - Introduction of device PM QoS flags.

 - ACPI device power management update allowing subsystems other than
   PCI to use it more easily.

 - ACPI device enumeration rework allowing additional kinds of devices
   to be enumerated via ACPI.  From Mika Westerberg, Adrian Hunter,
   Mathias Nyman, Andy Shevchenko, and Rafael J. Wysocki.

 - ACPICA update to version 20121018 from Bob Moore and Lv Zheng.

 - ACPI memory hotplug update from Wen Congyang and Yasuaki Ishimatsu.

 - Introduction of acpi_handle_<level>() messaging macros and ACPI-based
   CPU hot-remove support from Toshi Kani.

 - ACPI EC updates from Feng Tang.

 - cpufreq updates from Viresh Kumar, Fabio Baltieri and others.

 - cpuidle changes to quickly notice governor prediction failure from
   Youquan Song.

 - Support for using multiple cpuidle drivers at the same time and
   cpuidle cleanups from Daniel Lezcano.

 - devfreq updates from Nishanth Menon and others.

 - cpupower update from Thomas Renninger.

 - Fixes and small cleanups all over the place.

* tag 'pm+acpi-for-3.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (196 commits)
  mmc: sdhci-acpi: enable runtime-pm for device HID INT33C6
  ACPI: add Haswell LPSS devices to acpi_platform_device_ids list
  ACPI: add documentation about ACPI 5 enumeration
  pnpacpi: fix incorrect TEST_ALPHA() test
  ACPI / PM: Fix header of acpi_dev_pm_detach() in acpi.h
  ACPI / video: ignore BIOS initial backlight value for HP Folio 13-2000
  ACPI : do not use Lid and Sleep button for S5 wakeup
  ACPI / PNP: Do not crash due to stale pointer use during system resume
  ACPI / video: Add "Asus UL30VT" to ACPI video detect blacklist
  ACPI: do acpisleep dmi check when CONFIG_ACPI_SLEEP is set
  spi / ACPI: add ACPI enumeration support
  gpio / ACPI: add ACPI support
  PM / devfreq: remove compiler error with module governors (2)
  cpupower: IvyBridge (0x3a and 0x3e models) support
  cpupower: Provide -c param for cpupower monitor to schedule process on all cores
  cpupower tools: Fix warning and a bug with the cpu package count
  cpupower tools: Fix malloc of cpu_info structure
  cpupower tools: Fix issues with sysfs_topology_read_file
  cpupower tools: Fix minor warnings
  cpupower tools: Update .gitignore for files created in the debug directories
  ...
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Linus Torvalds committed Dec 11, 2012
2 parents b58ed04 + f316fc5 commit bad73c5
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Showing 233 changed files with 9,470 additions and 3,326 deletions.
44 changes: 36 additions & 8 deletions Documentation/ABI/testing/sysfs-class-devfreq
Original file line number Diff line number Diff line change
Expand Up @@ -11,23 +11,24 @@ What: /sys/class/devfreq/.../governor
Date: September 2011
Contact: MyungJoo Ham <myungjoo.ham@samsung.com>
Description:
The /sys/class/devfreq/.../governor shows the name of the
The /sys/class/devfreq/.../governor show or set the name of the
governor used by the corresponding devfreq object.

What: /sys/class/devfreq/.../cur_freq
Date: September 2011
Contact: MyungJoo Ham <myungjoo.ham@samsung.com>
Description:
The /sys/class/devfreq/.../cur_freq shows the current
frequency of the corresponding devfreq object.
frequency of the corresponding devfreq object. Same as
target_freq when get_cur_freq() is not implemented by
devfreq driver.

What: /sys/class/devfreq/.../central_polling
Date: September 2011
Contact: MyungJoo Ham <myungjoo.ham@samsung.com>
What: /sys/class/devfreq/.../target_freq
Date: September 2012
Contact: Rajagopal Venkat <rajagopal.venkat@linaro.org>
Description:
The /sys/class/devfreq/.../central_polling shows whether
the devfreq ojbect is using devfreq-provided central
polling mechanism or not.
The /sys/class/devfreq/.../target_freq shows the next governor
predicted target frequency of the corresponding devfreq object.

What: /sys/class/devfreq/.../polling_interval
Date: September 2011
Expand All @@ -43,10 +44,37 @@ Description:
(/sys/class/devfreq/.../central_polling is 0), this value
may be useless.

What: /sys/class/devfreq/.../trans_stat
Date: October 2012
Contact: MyungJoo Ham <myungjoo.ham@samsung.com>
Descrtiption:
This ABI shows the statistics of devfreq behavior on a
specific device. It shows the time spent in each state and
the number of transitions between states.
In order to activate this ABI, the devfreq target device
driver should provide the list of available frequencies
with its profile.

What: /sys/class/devfreq/.../userspace/set_freq
Date: September 2011
Contact: MyungJoo Ham <myungjoo.ham@samsung.com>
Description:
The /sys/class/devfreq/.../userspace/set_freq shows and
sets the requested frequency for the devfreq object if
userspace governor is in effect.

What: /sys/class/devfreq/.../available_frequencies
Date: October 2012
Contact: Nishanth Menon <nm@ti.com>
Description:
The /sys/class/devfreq/.../available_frequencies shows
the available frequencies of the corresponding devfreq object.
This is a snapshot of available frequencies and not limited
by the min/max frequency restrictions.

What: /sys/class/devfreq/.../available_governors
Date: October 2012
Contact: Nishanth Menon <nm@ti.com>
Description:
The /sys/class/devfreq/.../available_governors shows
currently available governors in the system.
31 changes: 31 additions & 0 deletions Documentation/ABI/testing/sysfs-devices-power
Original file line number Diff line number Diff line change
Expand Up @@ -204,3 +204,34 @@ Description:

This attribute has no effect on system-wide suspend/resume and
hibernation.

What: /sys/devices/.../power/pm_qos_no_power_off
Date: September 2012
Contact: Rafael J. Wysocki <rjw@sisk.pl>
Description:
The /sys/devices/.../power/pm_qos_no_power_off attribute
is used for manipulating the PM QoS "no power off" flag. If
set, this flag indicates to the kernel that power should not
be removed entirely from the device.

Not all drivers support this attribute. If it isn't supported,
it is not present.

This attribute has no effect on system-wide suspend/resume and
hibernation.

What: /sys/devices/.../power/pm_qos_remote_wakeup
Date: September 2012
Contact: Rafael J. Wysocki <rjw@sisk.pl>
Description:
The /sys/devices/.../power/pm_qos_remote_wakeup attribute
is used for manipulating the PM QoS "remote wakeup required"
flag. If set, this flag indicates to the kernel that the
device is a source of user events that have to be signaled from
its low-power states.

Not all drivers support this attribute. If it isn't supported,
it is not present.

This attribute has no effect on system-wide suspend/resume and
hibernation.
14 changes: 14 additions & 0 deletions Documentation/ABI/testing/sysfs-devices-sun
Original file line number Diff line number Diff line change
@@ -0,0 +1,14 @@
Whatt: /sys/devices/.../sun
Date: October 2012
Contact: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Description:
The file contains a Slot-unique ID which provided by the _SUN
method in the ACPI namespace. The value is written in Advanced
Configuration and Power Interface Specification as follows:

"The _SUN value is required to be unique among the slots of
the same type. It is also recommended that this number match
the slot number printed on the physical slot whenever possible."

So reading the sysfs file, we can identify a physical position
of the slot in the system.
227 changes: 227 additions & 0 deletions Documentation/acpi/enumeration.txt
Original file line number Diff line number Diff line change
@@ -0,0 +1,227 @@
ACPI based device enumeration
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
ACPI 5 introduced a set of new resources (UartTSerialBus, I2cSerialBus,
SpiSerialBus, GpioIo and GpioInt) which can be used in enumerating slave
devices behind serial bus controllers.

In addition we are starting to see peripherals integrated in the
SoC/Chipset to appear only in ACPI namespace. These are typically devices
that are accessed through memory-mapped registers.

In order to support this and re-use the existing drivers as much as
possible we decided to do following:

o Devices that have no bus connector resource are represented as
platform devices.

o Devices behind real busses where there is a connector resource
are represented as struct spi_device or struct i2c_device
(standard UARTs are not busses so there is no struct uart_device).

As both ACPI and Device Tree represent a tree of devices (and their
resources) this implementation follows the Device Tree way as much as
possible.

The ACPI implementation enumerates devices behind busses (platform, SPI and
I2C), creates the physical devices and binds them to their ACPI handle in
the ACPI namespace.

This means that when ACPI_HANDLE(dev) returns non-NULL the device was
enumerated from ACPI namespace. This handle can be used to extract other
device-specific configuration. There is an example of this below.

Platform bus support
~~~~~~~~~~~~~~~~~~~~
Since we are using platform devices to represent devices that are not
connected to any physical bus we only need to implement a platform driver
for the device and add supported ACPI IDs. If this same IP-block is used on
some other non-ACPI platform, the driver might work out of the box or needs
some minor changes.

Adding ACPI support for an existing driver should be pretty
straightforward. Here is the simplest example:

#ifdef CONFIG_ACPI
static struct acpi_device_id mydrv_acpi_match[] = {
/* ACPI IDs here */
{ }
};
MODULE_DEVICE_TABLE(acpi, mydrv_acpi_match);
#endif

static struct platform_driver my_driver = {
...
.driver = {
.acpi_match_table = ACPI_PTR(mydrv_acpi_match),
},
};

If the driver needs to perform more complex initialization like getting and
configuring GPIOs it can get its ACPI handle and extract this information
from ACPI tables.

Currently the kernel is not able to automatically determine from which ACPI
device it should make the corresponding platform device so we need to add
the ACPI device explicitly to acpi_platform_device_ids list defined in
drivers/acpi/scan.c. This limitation is only for the platform devices, SPI
and I2C devices are created automatically as described below.

SPI serial bus support
~~~~~~~~~~~~~~~~~~~~~~
Slave devices behind SPI bus have SpiSerialBus resource attached to them.
This is extracted automatically by the SPI core and the slave devices are
enumerated once spi_register_master() is called by the bus driver.

Here is what the ACPI namespace for a SPI slave might look like:

Device (EEP0)
{
Name (_ADR, 1)
Name (_CID, Package() {
"ATML0025",
"AT25",
})
...
Method (_CRS, 0, NotSerialized)
{
SPISerialBus(1, PolarityLow, FourWireMode, 8,
ControllerInitiated, 1000000, ClockPolarityLow,
ClockPhaseFirst, "\\_SB.PCI0.SPI1",)
}
...

The SPI device drivers only need to add ACPI IDs in a similar way than with
the platform device drivers. Below is an example where we add ACPI support
to at25 SPI eeprom driver (this is meant for the above ACPI snippet):

#ifdef CONFIG_ACPI
static struct acpi_device_id at25_acpi_match[] = {
{ "AT25", 0 },
{ },
};
MODULE_DEVICE_TABLE(acpi, at25_acpi_match);
#endif

static struct spi_driver at25_driver = {
.driver = {
...
.acpi_match_table = ACPI_PTR(at25_acpi_match),
},
};

Note that this driver actually needs more information like page size of the
eeprom etc. but at the time writing this there is no standard way of
passing those. One idea is to return this in _DSM method like:

Device (EEP0)
{
...
Method (_DSM, 4, NotSerialized)
{
Store (Package (6)
{
"byte-len", 1024,
"addr-mode", 2,
"page-size, 32
}, Local0)

// Check UUIDs etc.

Return (Local0)
}

Then the at25 SPI driver can get this configation by calling _DSM on its
ACPI handle like:

struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
struct acpi_object_list input;
acpi_status status;

/* Fill in the input buffer */

status = acpi_evaluate_object(ACPI_HANDLE(&spi->dev), "_DSM",
&input, &output);
if (ACPI_FAILURE(status))
/* Handle the error */

/* Extract the data here */

kfree(output.pointer);

I2C serial bus support
~~~~~~~~~~~~~~~~~~~~~~
The slaves behind I2C bus controller only need to add the ACPI IDs like
with the platform and SPI drivers. However the I2C bus controller driver
needs to call acpi_i2c_register_devices() after it has added the adapter.

An I2C bus (controller) driver does:

...
ret = i2c_add_numbered_adapter(adapter);
if (ret)
/* handle error */

of_i2c_register_devices(adapter);
/* Enumerate the slave devices behind this bus via ACPI */
acpi_i2c_register_devices(adapter);

Below is an example of how to add ACPI support to the existing mpu3050
input driver:

#ifdef CONFIG_ACPI
static struct acpi_device_id mpu3050_acpi_match[] = {
{ "MPU3050", 0 },
{ },
};
MODULE_DEVICE_TABLE(acpi, mpu3050_acpi_match);
#endif

static struct i2c_driver mpu3050_i2c_driver = {
.driver = {
.name = "mpu3050",
.owner = THIS_MODULE,
.pm = &mpu3050_pm,
.of_match_table = mpu3050_of_match,
.acpi_match_table ACPI_PTR(mpu3050_acpi_match),
},
.probe = mpu3050_probe,
.remove = __devexit_p(mpu3050_remove),
.id_table = mpu3050_ids,
};

GPIO support
~~~~~~~~~~~~
ACPI 5 introduced two new resources to describe GPIO connections: GpioIo
and GpioInt. These resources are used be used to pass GPIO numbers used by
the device to the driver. For example:

Method (_CRS, 0, NotSerialized)
{
Name (SBUF, ResourceTemplate()
{
GpioIo (Exclusive, PullDefault, 0x0000, 0x0000,
IoRestrictionOutputOnly, "\\_SB.PCI0.GPI0",
0x00, ResourceConsumer,,)
{
// Pin List
0x0055
}
...

Return (SBUF)
}
}

These GPIO numbers are controller relative and path "\\_SB.PCI0.GPI0"
specifies the path to the controller. In order to use these GPIOs in Linux
we need to translate them to the Linux GPIO numbers.

The driver can do this by including <linux/acpi_gpio.h> and then calling
acpi_get_gpio(path, gpio). This will return the Linux GPIO number or
negative errno if there was no translation found.

Other GpioIo parameters must be converted first by the driver to be
suitable to the gpiolib before passing them.

In case of GpioInt resource an additional call to gpio_to_irq() must be
done before calling request_irq().
42 changes: 42 additions & 0 deletions Documentation/devicetree/bindings/cpufreq/cpufreq-spear.txt
Original file line number Diff line number Diff line change
@@ -0,0 +1,42 @@
SPEAr cpufreq driver
-------------------

SPEAr SoC cpufreq driver for CPU frequency scaling.
It supports both uniprocessor (UP) and symmetric multiprocessor (SMP) systems
which share clock across all CPUs.

Required properties:
- cpufreq_tbl: Table of frequencies CPU could be transitioned into, in the
increasing order.

Optional properties:
- clock-latency: Specify the possible maximum transition latency for clock, in
unit of nanoseconds.

Both required and optional properties listed above must be defined under node
/cpus/cpu@0.

Examples:
--------
cpus {

<...>

cpu@0 {
compatible = "arm,cortex-a9";
reg = <0>;

<...>

cpufreq_tbl = < 166000
200000
250000
300000
400000
500000
600000 >;
};

<...>

};
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