diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2015-02-11 02:09:41 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-02-11 02:09:41 +0300 |
commit | 872912352c5be930e9568e5f3b6d73107d9f278d (patch) | |
tree | ecc18608e200307588ac5130774518a54a292756 /drivers/devfreq/devfreq-event.c | |
parent | c08f8467939e7d2eebcba7cf2330242c4f53f2f7 (diff) | |
parent | b5e82233cab43c25fc0a1c28d9136a086db4aa52 (diff) | |
download | linux-872912352c5be930e9568e5f3b6d73107d9f278d.tar.xz |
Merge tag 'pm+acpi-3.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI and power management updates from Rafael Wysocki:
"We have a few new features this time, including a new SFI-based
cpufreq driver, a new devfreq driver for Tegra Activity Monitor, a new
devfreq class for providing its governors with raw utilization data
and a new ACPI driver for AMD SoCs.
Still, the majority of changes here are reworks of existing code to
make it more straightforward or to prepare it for implementing new
features on top of it. The primary example is the rework of ACPI
resources handling from Jiang Liu, Thomas Gleixner and Lv Zheng with
support for IOAPIC hotplug implemented on top of it, but there is
quite a number of changes of this kind in the cpufreq core, ACPICA,
ACPI EC driver, ACPI processor driver and the generic power domains
core code too.
The most active developer is Viresh Kumar with his cpufreq changes.
Specifics:
- Rework of the core ACPI resources parsing code to fix issues in it
and make using resource offsets more convenient and consolidation
of some resource-handing code in a couple of places that have grown
analagous data structures and code to cover the the same gap in the
core (Jiang Liu, Thomas Gleixner, Lv Zheng).
- ACPI-based IOAPIC hotplug support on top of the resources handling
rework (Jiang Liu, Yinghai Lu).
- ACPICA update to upstream release 20150204 including an interrupt
handling rework that allows drivers to install raw handlers for
ACPI GPEs which then become entirely responsible for the given GPE
and the ACPICA core code won't touch it (Lv Zheng, David E Box,
Octavian Purdila).
- ACPI EC driver rework to fix several concurrency issues and other
problems related to events handling on top of the ACPICA's new
support for raw GPE handlers (Lv Zheng).
- New ACPI driver for AMD SoCs analogous to the LPSS (Low-Power
Subsystem) driver for Intel chips (Ken Xue).
- Two minor fixes of the ACPI LPSS driver (Heikki Krogerus, Jarkko
Nikula).
- Two new blacklist entries for machines (Samsung 730U3E/740U3E and
510R) where the native backlight interface doesn't work correctly
while the ACPI one does (Hans de Goede).
- Rework of the ACPI processor driver's handling of idle states to
make the code more straightforward and less bloated overall (Rafael
J Wysocki).
- Assorted minor fixes related to ACPI and SFI (Andreas Ruprecht,
Andy Shevchenko, Hanjun Guo, Jan Beulich, Rafael J Wysocki, Yaowei
Bai).
- PCI core power management modification to avoid resuming (some)
runtime-suspended devices during system suspend if they are in the
right states already (Rafael J Wysocki).
- New SFI-based cpufreq driver for Intel platforms using SFI
(Srinidhi Kasagar).
- cpufreq core fixes, cleanups and simplifications (Viresh Kumar,
Doug Anderson, Wolfram Sang).
- SkyLake CPU support and other updates for the intel_pstate driver
(Kristen Carlson Accardi, Srinivas Pandruvada).
- cpufreq-dt driver cleanup (Markus Elfring).
- Init fix for the ARM big.LITTLE cpuidle driver (Sudeep Holla).
- Generic power domains core code fixes and cleanups (Ulf Hansson).
- Operating Performance Points (OPP) core code cleanups and kernel
documentation update (Nishanth Menon).
- New dabugfs interface to make the list of PM QoS constraints
available to user space (Nishanth Menon).
- New devfreq driver for Tegra Activity Monitor (Tomeu Vizoso).
- New devfreq class (devfreq_event) to provide raw utilization data
to devfreq governors (Chanwoo Choi).
- Assorted minor fixes and cleanups related to power management
(Andreas Ruprecht, Krzysztof Kozlowski, Rickard Strandqvist, Pavel
Machek, Todd E Brandt, Wonhong Kwon).
- turbostat updates (Len Brown) and cpupower Makefile improvement
(Sriram Raghunathan)"
* tag 'pm+acpi-3.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (151 commits)
tools/power turbostat: relax dependency on APERF_MSR
tools/power turbostat: relax dependency on invariant TSC
Merge branch 'pci/host-generic' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci into acpi-resources
tools/power turbostat: decode MSR_*_PERF_LIMIT_REASONS
tools/power turbostat: relax dependency on root permission
ACPI / video: Add disable_native_backlight quirk for Samsung 510R
ACPI / PM: Remove unneeded nested #ifdef
USB / PM: Remove unneeded #ifdef and associated dead code
intel_pstate: provide option to only use intel_pstate with HWP
ACPI / EC: Add GPE reference counting debugging messages
ACPI / EC: Add query flushing support
ACPI / EC: Refine command storm prevention support
ACPI / EC: Add command flushing support.
ACPI / EC: Introduce STARTED/STOPPED flags to replace BLOCKED flag
ACPI: add AMD ACPI2Platform device support for x86 system
ACPI / table: remove duplicate NULL check for the handler of acpi_table_parse()
ACPI / EC: Update revision due to raw handler mode.
ACPI / EC: Reduce ec_poll() by referencing the last register access timestamp.
ACPI / EC: Fix several GPE handling issues by deploying ACPI_GPE_DISPATCH_RAW_HANDLER mode.
ACPICA: Events: Enable APIs to allow interrupt/polling adaptive request based GPE handling model
...
Diffstat (limited to 'drivers/devfreq/devfreq-event.c')
-rw-r--r-- | drivers/devfreq/devfreq-event.c | 494 |
1 files changed, 494 insertions, 0 deletions
diff --git a/drivers/devfreq/devfreq-event.c b/drivers/devfreq/devfreq-event.c new file mode 100644 index 000000000000..f304a0289eda --- /dev/null +++ b/drivers/devfreq/devfreq-event.c @@ -0,0 +1,494 @@ +/* + * devfreq-event: a framework to provide raw data and events of devfreq devices + * + * Copyright (C) 2015 Samsung Electronics + * Author: Chanwoo Choi <cw00.choi@samsung.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This driver is based on drivers/devfreq/devfreq.c. + */ + +#include <linux/devfreq-event.h> +#include <linux/kernel.h> +#include <linux/err.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/list.h> +#include <linux/of.h> + +static struct class *devfreq_event_class; + +/* The list of all devfreq event list */ +static LIST_HEAD(devfreq_event_list); +static DEFINE_MUTEX(devfreq_event_list_lock); + +#define to_devfreq_event(DEV) container_of(DEV, struct devfreq_event_dev, dev) + +/** + * devfreq_event_enable_edev() - Enable the devfreq-event dev and increase + * the enable_count of devfreq-event dev. + * @edev : the devfreq-event device + * + * Note that this function increase the enable_count and enable the + * devfreq-event device. The devfreq-event device should be enabled before + * using it by devfreq device. + */ +int devfreq_event_enable_edev(struct devfreq_event_dev *edev) +{ + int ret = 0; + + if (!edev || !edev->desc) + return -EINVAL; + + mutex_lock(&edev->lock); + if (edev->desc->ops && edev->desc->ops->enable + && edev->enable_count == 0) { + ret = edev->desc->ops->enable(edev); + if (ret < 0) + goto err; + } + edev->enable_count++; +err: + mutex_unlock(&edev->lock); + + return ret; +} +EXPORT_SYMBOL_GPL(devfreq_event_enable_edev); + +/** + * devfreq_event_disable_edev() - Disable the devfreq-event dev and decrease + * the enable_count of the devfreq-event dev. + * @edev : the devfreq-event device + * + * Note that this function decrease the enable_count and disable the + * devfreq-event device. After the devfreq-event device is disabled, + * devfreq device can't use the devfreq-event device for get/set/reset + * operations. + */ +int devfreq_event_disable_edev(struct devfreq_event_dev *edev) +{ + int ret = 0; + + if (!edev || !edev->desc) + return -EINVAL; + + mutex_lock(&edev->lock); + if (edev->enable_count <= 0) { + dev_warn(&edev->dev, "unbalanced enable_count\n"); + ret = -EIO; + goto err; + } + + if (edev->desc->ops && edev->desc->ops->disable + && edev->enable_count == 1) { + ret = edev->desc->ops->disable(edev); + if (ret < 0) + goto err; + } + edev->enable_count--; +err: + mutex_unlock(&edev->lock); + + return ret; +} +EXPORT_SYMBOL_GPL(devfreq_event_disable_edev); + +/** + * devfreq_event_is_enabled() - Check whether devfreq-event dev is enabled or + * not. + * @edev : the devfreq-event device + * + * Note that this function check whether devfreq-event dev is enabled or not. + * If return true, the devfreq-event dev is enabeld. If return false, the + * devfreq-event dev is disabled. + */ +bool devfreq_event_is_enabled(struct devfreq_event_dev *edev) +{ + bool enabled = false; + + if (!edev || !edev->desc) + return enabled; + + mutex_lock(&edev->lock); + + if (edev->enable_count > 0) + enabled = true; + + mutex_unlock(&edev->lock); + + return enabled; +} +EXPORT_SYMBOL_GPL(devfreq_event_is_enabled); + +/** + * devfreq_event_set_event() - Set event to devfreq-event dev to start. + * @edev : the devfreq-event device + * + * Note that this function set the event to the devfreq-event device to start + * for getting the event data which could be various event type. + */ +int devfreq_event_set_event(struct devfreq_event_dev *edev) +{ + int ret; + + if (!edev || !edev->desc) + return -EINVAL; + + if (!edev->desc->ops || !edev->desc->ops->set_event) + return -EINVAL; + + if (!devfreq_event_is_enabled(edev)) + return -EPERM; + + mutex_lock(&edev->lock); + ret = edev->desc->ops->set_event(edev); + mutex_unlock(&edev->lock); + + return ret; +} +EXPORT_SYMBOL_GPL(devfreq_event_set_event); + +/** + * devfreq_event_get_event() - Get {load|total}_count from devfreq-event dev. + * @edev : the devfreq-event device + * @edata : the calculated data of devfreq-event device + * + * Note that this function get the calculated event data from devfreq-event dev + * after stoping the progress of whole sequence of devfreq-event dev. + */ +int devfreq_event_get_event(struct devfreq_event_dev *edev, + struct devfreq_event_data *edata) +{ + int ret; + + if (!edev || !edev->desc) + return -EINVAL; + + if (!edev->desc->ops || !edev->desc->ops->get_event) + return -EINVAL; + + if (!devfreq_event_is_enabled(edev)) + return -EINVAL; + + edata->total_count = edata->load_count = 0; + + mutex_lock(&edev->lock); + ret = edev->desc->ops->get_event(edev, edata); + if (ret < 0) + edata->total_count = edata->load_count = 0; + mutex_unlock(&edev->lock); + + return ret; +} +EXPORT_SYMBOL_GPL(devfreq_event_get_event); + +/** + * devfreq_event_reset_event() - Reset all opeations of devfreq-event dev. + * @edev : the devfreq-event device + * + * Note that this function stop all operations of devfreq-event dev and reset + * the current event data to make the devfreq-event device into initial state. + */ +int devfreq_event_reset_event(struct devfreq_event_dev *edev) +{ + int ret = 0; + + if (!edev || !edev->desc) + return -EINVAL; + + if (!devfreq_event_is_enabled(edev)) + return -EPERM; + + mutex_lock(&edev->lock); + if (edev->desc->ops && edev->desc->ops->reset) + ret = edev->desc->ops->reset(edev); + mutex_unlock(&edev->lock); + + return ret; +} +EXPORT_SYMBOL_GPL(devfreq_event_reset_event); + +/** + * devfreq_event_get_edev_by_phandle() - Get the devfreq-event dev from + * devicetree. + * @dev : the pointer to the given device + * @index : the index into list of devfreq-event device + * + * Note that this function return the pointer of devfreq-event device. + */ +struct devfreq_event_dev *devfreq_event_get_edev_by_phandle(struct device *dev, + int index) +{ + struct device_node *node; + struct devfreq_event_dev *edev; + + if (!dev->of_node) { + dev_err(dev, "device does not have a device node entry\n"); + return ERR_PTR(-EINVAL); + } + + node = of_parse_phandle(dev->of_node, "devfreq-events", index); + if (!node) { + dev_err(dev, "failed to get phandle in %s node\n", + dev->of_node->full_name); + return ERR_PTR(-ENODEV); + } + + mutex_lock(&devfreq_event_list_lock); + list_for_each_entry(edev, &devfreq_event_list, node) { + if (!strcmp(edev->desc->name, node->name)) + goto out; + } + edev = NULL; +out: + mutex_unlock(&devfreq_event_list_lock); + + if (!edev) { + dev_err(dev, "unable to get devfreq-event device : %s\n", + node->name); + of_node_put(node); + return ERR_PTR(-ENODEV); + } + + of_node_put(node); + + return edev; +} +EXPORT_SYMBOL_GPL(devfreq_event_get_edev_by_phandle); + +/** + * devfreq_event_get_edev_count() - Get the count of devfreq-event dev + * @dev : the pointer to the given device + * + * Note that this function return the count of devfreq-event devices. + */ +int devfreq_event_get_edev_count(struct device *dev) +{ + int count; + + if (!dev->of_node) { + dev_err(dev, "device does not have a device node entry\n"); + return -EINVAL; + } + + count = of_property_count_elems_of_size(dev->of_node, "devfreq-events", + sizeof(u32)); + if (count < 0 ) { + dev_err(dev, + "failed to get the count of devfreq-event in %s node\n", + dev->of_node->full_name); + return count; + } + + return count; +} +EXPORT_SYMBOL_GPL(devfreq_event_get_edev_count); + +static void devfreq_event_release_edev(struct device *dev) +{ + struct devfreq_event_dev *edev = to_devfreq_event(dev); + + kfree(edev); +} + +/** + * devfreq_event_add_edev() - Add new devfreq-event device. + * @dev : the device owning the devfreq-event device being created + * @desc : the devfreq-event device's decriptor which include essential + * data for devfreq-event device. + * + * Note that this function add new devfreq-event device to devfreq-event class + * list and register the device of the devfreq-event device. + */ +struct devfreq_event_dev *devfreq_event_add_edev(struct device *dev, + struct devfreq_event_desc *desc) +{ + struct devfreq_event_dev *edev; + static atomic_t event_no = ATOMIC_INIT(0); + int ret; + + if (!dev || !desc) + return ERR_PTR(-EINVAL); + + if (!desc->name || !desc->ops) + return ERR_PTR(-EINVAL); + + if (!desc->ops->set_event || !desc->ops->get_event) + return ERR_PTR(-EINVAL); + + edev = kzalloc(sizeof(struct devfreq_event_dev), GFP_KERNEL); + if (!edev) + return ERR_PTR(-ENOMEM); + + mutex_init(&edev->lock); + edev->desc = desc; + edev->enable_count = 0; + edev->dev.parent = dev; + edev->dev.class = devfreq_event_class; + edev->dev.release = devfreq_event_release_edev; + + dev_set_name(&edev->dev, "event.%d", atomic_inc_return(&event_no) - 1); + ret = device_register(&edev->dev); + if (ret < 0) { + put_device(&edev->dev); + return ERR_PTR(ret); + } + dev_set_drvdata(&edev->dev, edev); + + INIT_LIST_HEAD(&edev->node); + + mutex_lock(&devfreq_event_list_lock); + list_add(&edev->node, &devfreq_event_list); + mutex_unlock(&devfreq_event_list_lock); + + return edev; +} +EXPORT_SYMBOL_GPL(devfreq_event_add_edev); + +/** + * devfreq_event_remove_edev() - Remove the devfreq-event device registered. + * @dev : the devfreq-event device + * + * Note that this function remove the registered devfreq-event device. + */ +int devfreq_event_remove_edev(struct devfreq_event_dev *edev) +{ + if (!edev) + return -EINVAL; + + WARN_ON(edev->enable_count); + + mutex_lock(&devfreq_event_list_lock); + list_del(&edev->node); + mutex_unlock(&devfreq_event_list_lock); + + device_unregister(&edev->dev); + + return 0; +} +EXPORT_SYMBOL_GPL(devfreq_event_remove_edev); + +static int devm_devfreq_event_match(struct device *dev, void *res, void *data) +{ + struct devfreq_event_dev **r = res; + + if (WARN_ON(!r || !*r)) + return 0; + + return *r == data; +} + +static void devm_devfreq_event_release(struct device *dev, void *res) +{ + devfreq_event_remove_edev(*(struct devfreq_event_dev **)res); +} + +/** + * devm_devfreq_event_add_edev() - Resource-managed devfreq_event_add_edev() + * @dev : the device owning the devfreq-event device being created + * @desc : the devfreq-event device's decriptor which include essential + * data for devfreq-event device. + * + * Note that this function manages automatically the memory of devfreq-event + * device using device resource management and simplify the free operation + * for memory of devfreq-event device. + */ +struct devfreq_event_dev *devm_devfreq_event_add_edev(struct device *dev, + struct devfreq_event_desc *desc) +{ + struct devfreq_event_dev **ptr, *edev; + + ptr = devres_alloc(devm_devfreq_event_release, sizeof(*ptr), GFP_KERNEL); + if (!ptr) + return ERR_PTR(-ENOMEM); + + edev = devfreq_event_add_edev(dev, desc); + if (IS_ERR(edev)) { + devres_free(ptr); + return ERR_PTR(-ENOMEM); + } + + *ptr = edev; + devres_add(dev, ptr); + + return edev; +} +EXPORT_SYMBOL_GPL(devm_devfreq_event_add_edev); + +/** + * devm_devfreq_event_remove_edev()- Resource-managed devfreq_event_remove_edev() + * @dev : the device owning the devfreq-event device being created + * @edev : the devfreq-event device + * + * Note that this function manages automatically the memory of devfreq-event + * device using device resource management. + */ +void devm_devfreq_event_remove_edev(struct device *dev, + struct devfreq_event_dev *edev) +{ + WARN_ON(devres_release(dev, devm_devfreq_event_release, + devm_devfreq_event_match, edev)); +} +EXPORT_SYMBOL_GPL(devm_devfreq_event_remove_edev); + +/* + * Device attributes for devfreq-event class. + */ +static ssize_t name_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct devfreq_event_dev *edev = to_devfreq_event(dev); + + if (!edev || !edev->desc) + return -EINVAL; + + return sprintf(buf, "%s\n", edev->desc->name); +} +static DEVICE_ATTR_RO(name); + +static ssize_t enable_count_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct devfreq_event_dev *edev = to_devfreq_event(dev); + + if (!edev || !edev->desc) + return -EINVAL; + + return sprintf(buf, "%d\n", edev->enable_count); +} +static DEVICE_ATTR_RO(enable_count); + +static struct attribute *devfreq_event_attrs[] = { + &dev_attr_name.attr, + &dev_attr_enable_count.attr, + NULL, +}; +ATTRIBUTE_GROUPS(devfreq_event); + +static int __init devfreq_event_init(void) +{ + devfreq_event_class = class_create(THIS_MODULE, "devfreq-event"); + if (IS_ERR(devfreq_event_class)) { + pr_err("%s: couldn't create class\n", __FILE__); + return PTR_ERR(devfreq_event_class); + } + + devfreq_event_class->dev_groups = devfreq_event_groups; + + return 0; +} +subsys_initcall(devfreq_event_init); + +static void __exit devfreq_event_exit(void) +{ + class_destroy(devfreq_event_class); +} +module_exit(devfreq_event_exit); + +MODULE_AUTHOR("Chanwoo Choi <cw00.choi@samsung.com>"); +MODULE_DESCRIPTION("DEVFREQ-Event class support"); +MODULE_LICENSE("GPL"); |