[mirror_ubuntu-focal-kernel.git] / drivers / powercap / powercap_sys.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Power capping class
 * Copyright (c) 2013, Intel Corporation.
 */

#include <linux/module.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/powercap.h>

#define to_powercap_zone(n) container_of(n, struct powercap_zone, dev)
#define to_powercap_control_type(n) \
			container_of(n, struct powercap_control_type, dev)

/* Power zone show function */
#define define_power_zone_show(_attr)		\
static ssize_t _attr##_show(struct device *dev, \
					struct device_attribute *dev_attr,\
					char *buf) \
{ \
	u64 value; \
	ssize_t len = -EINVAL; \
	struct powercap_zone *power_zone = to_powercap_zone(dev); \
	\
	if (power_zone->ops->get_##_attr) { \
		if (!power_zone->ops->get_##_attr(power_zone, &value)) \
			len = sprintf(buf, "%lld\n", value); \
	} \
	\
	return len; \
}

/* The only meaningful input is 0 (reset), others are silently ignored */
#define define_power_zone_store(_attr)		\
static ssize_t _attr##_store(struct device *dev,\
				struct device_attribute *dev_attr, \
				const char *buf, size_t count) \
{ \
	int err; \
	struct powercap_zone *power_zone = to_powercap_zone(dev); \
	u64 value; \
	\
	err = kstrtoull(buf, 10, &value); \
	if (err) \
		return -EINVAL; \
	if (value) \
		return count; \
	if (power_zone->ops->reset_##_attr) { \
		if (!power_zone->ops->reset_##_attr(power_zone)) \
			return count; \
	} \
	\
	return -EINVAL; \
}

/* Power zone constraint show function */
#define define_power_zone_constraint_show(_attr) \
static ssize_t show_constraint_##_attr(struct device *dev, \
				struct device_attribute *dev_attr,\
				char *buf) \
{ \
	u64 value; \
	ssize_t len = -ENODATA; \
	struct powercap_zone *power_zone = to_powercap_zone(dev); \
	int id; \
	struct powercap_zone_constraint *pconst;\
	\
	if (!sscanf(dev_attr->attr.name, "constraint_%d_", &id)) \
		return -EINVAL; \
	if (id >= power_zone->const_id_cnt)	\
		return -EINVAL; \
	pconst = &power_zone->constraints[id]; \
	if (pconst && pconst->ops && pconst->ops->get_##_attr) { \
		if (!pconst->ops->get_##_attr(power_zone, id, &value)) \
			len = sprintf(buf, "%lld\n", value); \
	} \
	\
	return len; \
}

/* Power zone constraint store function */
#define define_power_zone_constraint_store(_attr) \
static ssize_t store_constraint_##_attr(struct device *dev,\
				struct device_attribute *dev_attr, \
				const char *buf, size_t count) \
{ \
	int err; \
	u64 value; \
	struct powercap_zone *power_zone = to_powercap_zone(dev); \
	int id; \
	struct powercap_zone_constraint *pconst;\
	\
	if (!sscanf(dev_attr->attr.name, "constraint_%d_", &id)) \
		return -EINVAL; \
	if (id >= power_zone->const_id_cnt)	\
		return -EINVAL; \
	pconst = &power_zone->constraints[id]; \
	err = kstrtoull(buf, 10, &value); \
	if (err) \
		return -EINVAL; \
	if (pconst && pconst->ops && pconst->ops->set_##_attr) { \
		if (!pconst->ops->set_##_attr(power_zone, id, value)) \
			return count; \
	} \
	\
	return -ENODATA; \
}

/* Power zone information callbacks */
define_power_zone_show(power_uw);
define_power_zone_show(max_power_range_uw);
define_power_zone_show(energy_uj);
define_power_zone_store(energy_uj);
define_power_zone_show(max_energy_range_uj);

/* Power zone attributes */
static DEVICE_ATTR_RO(max_power_range_uw);
static DEVICE_ATTR_RO(power_uw);
static DEVICE_ATTR_RO(max_energy_range_uj);
static DEVICE_ATTR_RW(energy_uj);

/* Power zone constraint attributes callbacks */
define_power_zone_constraint_show(power_limit_uw);
define_power_zone_constraint_store(power_limit_uw);
define_power_zone_constraint_show(time_window_us);
define_power_zone_constraint_store(time_window_us);
define_power_zone_constraint_show(max_power_uw);
define_power_zone_constraint_show(min_power_uw);
define_power_zone_constraint_show(max_time_window_us);
define_power_zone_constraint_show(min_time_window_us);

/* For one time seeding of constraint device attributes */
struct powercap_constraint_attr {
	struct device_attribute power_limit_attr;
	struct device_attribute time_window_attr;
	struct device_attribute max_power_attr;
	struct device_attribute min_power_attr;
	struct device_attribute max_time_window_attr;
	struct device_attribute min_time_window_attr;
	struct device_attribute name_attr;
};

static struct powercap_constraint_attr
				constraint_attrs[MAX_CONSTRAINTS_PER_ZONE];

/* A list of powercap control_types */
static LIST_HEAD(powercap_cntrl_list);
/* Mutex to protect list of powercap control_types */
static DEFINE_MUTEX(powercap_cntrl_list_lock);

#define POWERCAP_CONSTRAINT_NAME_LEN	30 /* Some limit to avoid overflow */
static ssize_t show_constraint_name(struct device *dev,
				struct device_attribute *dev_attr,
				char *buf)
{
	const char *name;
	struct powercap_zone *power_zone = to_powercap_zone(dev);
	int id;
	ssize_t len = -ENODATA;
	struct powercap_zone_constraint *pconst;

	if (!sscanf(dev_attr->attr.name, "constraint_%d_", &id))
		return -EINVAL;
	if (id >= power_zone->const_id_cnt)
		return -EINVAL;
	pconst = &power_zone->constraints[id];

	if (pconst && pconst->ops && pconst->ops->get_name) {
		name = pconst->ops->get_name(power_zone, id);
		if (name) {
			snprintf(buf, POWERCAP_CONSTRAINT_NAME_LEN,
								"%s\n", name);
			buf[POWERCAP_CONSTRAINT_NAME_LEN] = '\0';
			len = strlen(buf);
		}
	}

	return len;
}

static int create_constraint_attribute(int id, const char *name,
				int mode,
				struct device_attribute *dev_attr,
				ssize_t (*show)(struct device *,
					struct device_attribute *, char *),
				ssize_t (*store)(struct device *,
					struct device_attribute *,
				const char *, size_t)
				)
{

	dev_attr->attr.name = kasprintf(GFP_KERNEL, "constraint_%d_%s",
								id, name);
	if (!dev_attr->attr.name)
		return -ENOMEM;
	dev_attr->attr.mode = mode;
	dev_attr->show = show;
	dev_attr->store = store;

	return 0;
}

static void free_constraint_attributes(void)
{
	int i;

	for (i = 0; i < MAX_CONSTRAINTS_PER_ZONE; ++i) {
		kfree(constraint_attrs[i].power_limit_attr.attr.name);
		kfree(constraint_attrs[i].time_window_attr.attr.name);
		kfree(constraint_attrs[i].name_attr.attr.name);
		kfree(constraint_attrs[i].max_power_attr.attr.name);
		kfree(constraint_attrs[i].min_power_attr.attr.name);
		kfree(constraint_attrs[i].max_time_window_attr.attr.name);
		kfree(constraint_attrs[i].min_time_window_attr.attr.name);
	}
}

static int seed_constraint_attributes(void)
{
	int i;
	int ret;

	for (i = 0; i < MAX_CONSTRAINTS_PER_ZONE; ++i) {
		ret = create_constraint_attribute(i, "power_limit_uw",
					S_IWUSR | S_IRUGO,
					&constraint_attrs[i].power_limit_attr,
					show_constraint_power_limit_uw,
					store_constraint_power_limit_uw);
		if (ret)
			goto err_alloc;
		ret = create_constraint_attribute(i, "time_window_us",
					S_IWUSR | S_IRUGO,
					&constraint_attrs[i].time_window_attr,
					show_constraint_time_window_us,
					store_constraint_time_window_us);
		if (ret)
			goto err_alloc;
		ret = create_constraint_attribute(i, "name", S_IRUGO,
				&constraint_attrs[i].name_attr,
				show_constraint_name,
				NULL);
		if (ret)
			goto err_alloc;
		ret = create_constraint_attribute(i, "max_power_uw", S_IRUGO,
				&constraint_attrs[i].max_power_attr,
				show_constraint_max_power_uw,
				NULL);
		if (ret)
			goto err_alloc;
		ret = create_constraint_attribute(i, "min_power_uw", S_IRUGO,
				&constraint_attrs[i].min_power_attr,
				show_constraint_min_power_uw,
				NULL);
		if (ret)
			goto err_alloc;
		ret = create_constraint_attribute(i, "max_time_window_us",
				S_IRUGO,
				&constraint_attrs[i].max_time_window_attr,
				show_constraint_max_time_window_us,
				NULL);
		if (ret)
			goto err_alloc;
		ret = create_constraint_attribute(i, "min_time_window_us",
				S_IRUGO,
				&constraint_attrs[i].min_time_window_attr,
				show_constraint_min_time_window_us,
				NULL);
		if (ret)
			goto err_alloc;

	}

	return 0;

err_alloc:
	free_constraint_attributes();

	return ret;
}

static int create_constraints(struct powercap_zone *power_zone,
			int nr_constraints,
			const struct powercap_zone_constraint_ops *const_ops)
{
	int i;
	int ret = 0;
	int count;
	struct powercap_zone_constraint *pconst;

	if (!power_zone || !const_ops || !const_ops->get_power_limit_uw ||
					!const_ops->set_power_limit_uw ||
					!const_ops->get_time_window_us ||
					!const_ops->set_time_window_us)
		return -EINVAL;

	count = power_zone->zone_attr_count;
	for (i = 0; i < nr_constraints; ++i) {
		pconst = &power_zone->constraints[i];
		pconst->ops = const_ops;
		pconst->id = power_zone->const_id_cnt;
		power_zone->const_id_cnt++;
		power_zone->zone_dev_attrs[count++] =
				&constraint_attrs[i].power_limit_attr.attr;
		power_zone->zone_dev_attrs[count++] =
				&constraint_attrs[i].time_window_attr.attr;
		if (pconst->ops->get_name)
			power_zone->zone_dev_attrs[count++] =
				&constraint_attrs[i].name_attr.attr;
		if (pconst->ops->get_max_power_uw)
			power_zone->zone_dev_attrs[count++] =
				&constraint_attrs[i].max_power_attr.attr;
		if (pconst->ops->get_min_power_uw)
			power_zone->zone_dev_attrs[count++] =
				&constraint_attrs[i].min_power_attr.attr;
		if (pconst->ops->get_max_time_window_us)
			power_zone->zone_dev_attrs[count++] =
				&constraint_attrs[i].max_time_window_attr.attr;
		if (pconst->ops->get_min_time_window_us)
			power_zone->zone_dev_attrs[count++] =
				&constraint_attrs[i].min_time_window_attr.attr;
	}
	power_zone->zone_attr_count = count;

	return ret;
}

static bool control_type_valid(void *control_type)
{
	struct powercap_control_type *pos = NULL;
	bool found = false;

	mutex_lock(&powercap_cntrl_list_lock);

	list_for_each_entry(pos, &powercap_cntrl_list, node) {
		if (pos == control_type) {
			found = true;
			break;
		}
	}
	mutex_unlock(&powercap_cntrl_list_lock);

	return found;
}

static ssize_t name_show(struct device *dev,
				struct device_attribute *attr,
				char *buf)
{
	struct powercap_zone *power_zone = to_powercap_zone(dev);

	return sprintf(buf, "%s\n", power_zone->name);
}

static DEVICE_ATTR_RO(name);

/* Create zone and attributes in sysfs */
static void create_power_zone_common_attributes(
					struct powercap_zone *power_zone)
{
	int count = 0;

	power_zone->zone_dev_attrs[count++] = &dev_attr_name.attr;
	if (power_zone->ops->get_max_energy_range_uj)
		power_zone->zone_dev_attrs[count++] =
					&dev_attr_max_energy_range_uj.attr;
	if (power_zone->ops->get_energy_uj) {
		if (power_zone->ops->reset_energy_uj)
			dev_attr_energy_uj.attr.mode = S_IWUSR | S_IRUGO;
		else
			dev_attr_energy_uj.attr.mode = S_IRUGO;
		power_zone->zone_dev_attrs[count++] =
					&dev_attr_energy_uj.attr;
	}
	if (power_zone->ops->get_power_uw)
		power_zone->zone_dev_attrs[count++] =
					&dev_attr_power_uw.attr;
	if (power_zone->ops->get_max_power_range_uw)
		power_zone->zone_dev_attrs[count++] =
					&dev_attr_max_power_range_uw.attr;
	power_zone->zone_dev_attrs[count] = NULL;
	power_zone->zone_attr_count = count;
}

static void powercap_release(struct device *dev)
{
	bool allocated;

	if (dev->parent) {
		struct powercap_zone *power_zone = to_powercap_zone(dev);

		/* Store flag as the release() may free memory */
		allocated = power_zone->allocated;
		/* Remove id from parent idr struct */
		idr_remove(power_zone->parent_idr, power_zone->id);
		/* Destroy idrs allocated for this zone */
		idr_destroy(&power_zone->idr);
		kfree(power_zone->name);
		kfree(power_zone->zone_dev_attrs);
		kfree(power_zone->constraints);
		if (power_zone->ops->release)
			power_zone->ops->release(power_zone);
		if (allocated)
			kfree(power_zone);
	} else {
		struct powercap_control_type *control_type =
						to_powercap_control_type(dev);

		/* Store flag as the release() may free memory */
		allocated = control_type->allocated;
		idr_destroy(&control_type->idr);
		mutex_destroy(&control_type->lock);
		if (control_type->ops && control_type->ops->release)
			control_type->ops->release(control_type);
		if (allocated)
			kfree(control_type);
	}
}

static ssize_t enabled_show(struct device *dev,
				struct device_attribute *attr,
				char *buf)
{
	bool mode = true;

	/* Default is enabled */
	if (dev->parent) {
		struct powercap_zone *power_zone = to_powercap_zone(dev);
		if (power_zone->ops->get_enable)
			if (power_zone->ops->get_enable(power_zone, &mode))
				mode = false;
	} else {
		struct powercap_control_type *control_type =
						to_powercap_control_type(dev);
		if (control_type->ops && control_type->ops->get_enable)
			if (control_type->ops->get_enable(control_type, &mode))
				mode = false;
	}

	return sprintf(buf, "%d\n", mode);
}

static ssize_t enabled_store(struct device *dev,
				struct device_attribute *attr,
				const char *buf,  size_t len)
{
	bool mode;

	if (strtobool(buf, &mode))
		return -EINVAL;
	if (dev->parent) {
		struct powercap_zone *power_zone = to_powercap_zone(dev);
		if (power_zone->ops->set_enable)
			if (!power_zone->ops->set_enable(power_zone, mode))
				return len;
	} else {
		struct powercap_control_type *control_type =
						to_powercap_control_type(dev);
		if (control_type->ops && control_type->ops->set_enable)
			if (!control_type->ops->set_enable(control_type, mode))
				return len;
	}

	return -ENOSYS;
}

static DEVICE_ATTR_RW(enabled);

static struct attribute *powercap_attrs[] = {
	&dev_attr_enabled.attr,
	NULL,
};
ATTRIBUTE_GROUPS(powercap);

static struct class powercap_class = {
	.name = "powercap",
	.dev_release = powercap_release,
	.dev_groups = powercap_groups,
};

struct powercap_zone *powercap_register_zone(
			struct powercap_zone *power_zone,
			struct powercap_control_type *control_type,
			const char *name,
			struct powercap_zone *parent,
			const struct powercap_zone_ops *ops,
			int nr_constraints,
			const struct powercap_zone_constraint_ops *const_ops)
{
	int result;
	int nr_attrs;

	if (!name || !control_type || !ops ||
			nr_constraints > MAX_CONSTRAINTS_PER_ZONE ||
			(!ops->get_energy_uj && !ops->get_power_uw) ||
			!control_type_valid(control_type))
		return ERR_PTR(-EINVAL);

	if (power_zone) {
		if (!ops->release)
			return ERR_PTR(-EINVAL);
		memset(power_zone, 0, sizeof(*power_zone));
	} else {
		power_zone = kzalloc(sizeof(*power_zone), GFP_KERNEL);
		if (!power_zone)
			return ERR_PTR(-ENOMEM);
		power_zone->allocated = true;
	}
	power_zone->ops = ops;
	power_zone->control_type_inst = control_type;
	if (!parent) {
		power_zone->dev.parent = &control_type->dev;
		power_zone->parent_idr = &control_type->idr;
	} else {
		power_zone->dev.parent = &parent->dev;
		power_zone->parent_idr = &parent->idr;
	}
	power_zone->dev.class = &powercap_class;

	mutex_lock(&control_type->lock);
	/* Using idr to get the unique id */
	result = idr_alloc(power_zone->parent_idr, NULL, 0, 0, GFP_KERNEL);
	if (result < 0)
		goto err_idr_alloc;

	power_zone->id = result;
	idr_init(&power_zone->idr);
	result = -ENOMEM;
	power_zone->name = kstrdup(name, GFP_KERNEL);
	if (!power_zone->name)
		goto err_name_alloc;
	dev_set_name(&power_zone->dev, "%s:%x",
					dev_name(power_zone->dev.parent),
					power_zone->id);
	power_zone->constraints = kcalloc(nr_constraints,
					  sizeof(*power_zone->constraints),
					  GFP_KERNEL);
	if (!power_zone->constraints)
		goto err_const_alloc;

	nr_attrs = nr_constraints * POWERCAP_CONSTRAINTS_ATTRS +
						POWERCAP_ZONE_MAX_ATTRS + 1;
	power_zone->zone_dev_attrs = kcalloc(nr_attrs, sizeof(void *),
					     GFP_KERNEL);
	if (!power_zone->zone_dev_attrs)
		goto err_attr_alloc;
	create_power_zone_common_attributes(power_zone);
	result = create_constraints(power_zone, nr_constraints, const_ops);
	if (result)
		goto err_dev_ret;

	power_zone->zone_dev_attrs[power_zone->zone_attr_count] = NULL;
	power_zone->dev_zone_attr_group.attrs = power_zone->zone_dev_attrs;
	power_zone->dev_attr_groups[0] = &power_zone->dev_zone_attr_group;
	power_zone->dev_attr_groups[1] = NULL;
	power_zone->dev.groups = power_zone->dev_attr_groups;
	result = device_register(&power_zone->dev);
	if (result)
		goto err_dev_ret;

	control_type->nr_zones++;
	mutex_unlock(&control_type->lock);

	return power_zone;

err_dev_ret:
	kfree(power_zone->zone_dev_attrs);
err_attr_alloc:
	kfree(power_zone->constraints);
err_const_alloc:
	kfree(power_zone->name);
err_name_alloc:
	idr_remove(power_zone->parent_idr, power_zone->id);
err_idr_alloc:
	if (power_zone->allocated)
		kfree(power_zone);
	mutex_unlock(&control_type->lock);

	return ERR_PTR(result);
}
EXPORT_SYMBOL_GPL(powercap_register_zone);

int powercap_unregister_zone(struct powercap_control_type *control_type,
				struct powercap_zone *power_zone)
{
	if (!power_zone || !control_type)
		return -EINVAL;

	mutex_lock(&control_type->lock);
	control_type->nr_zones--;
	mutex_unlock(&control_type->lock);

	device_unregister(&power_zone->dev);

	return 0;
}
EXPORT_SYMBOL_GPL(powercap_unregister_zone);

struct powercap_control_type *powercap_register_control_type(
				struct powercap_control_type *control_type,
				const char *name,
				const struct powercap_control_type_ops *ops)
{
	int result;

	if (!name)
		return ERR_PTR(-EINVAL);
	if (control_type) {
		if (!ops || !ops->release)
			return ERR_PTR(-EINVAL);
		memset(control_type, 0, sizeof(*control_type));
	} else {
		control_type = kzalloc(sizeof(*control_type), GFP_KERNEL);
		if (!control_type)
			return ERR_PTR(-ENOMEM);
		control_type->allocated = true;
	}
	mutex_init(&control_type->lock);
	control_type->ops = ops;
	INIT_LIST_HEAD(&control_type->node);
	control_type->dev.class = &powercap_class;
	dev_set_name(&control_type->dev, "%s", name);
	result = device_register(&control_type->dev);
	if (result) {
		if (control_type->allocated)
			kfree(control_type);
		return ERR_PTR(result);
	}
	idr_init(&control_type->idr);

	mutex_lock(&powercap_cntrl_list_lock);
	list_add_tail(&control_type->node, &powercap_cntrl_list);
	mutex_unlock(&powercap_cntrl_list_lock);

	return control_type;
}
EXPORT_SYMBOL_GPL(powercap_register_control_type);

int powercap_unregister_control_type(struct powercap_control_type *control_type)
{
	struct powercap_control_type *pos = NULL;

	if (control_type->nr_zones) {
		dev_err(&control_type->dev, "Zones of this type still not freed\n");
		return -EINVAL;
	}
	mutex_lock(&powercap_cntrl_list_lock);
	list_for_each_entry(pos, &powercap_cntrl_list, node) {
		if (pos == control_type) {
			list_del(&control_type->node);
			mutex_unlock(&powercap_cntrl_list_lock);
			device_unregister(&control_type->dev);
			return 0;
		}
	}
	mutex_unlock(&powercap_cntrl_list_lock);

	return -ENODEV;
}
EXPORT_SYMBOL_GPL(powercap_unregister_control_type);

static int __init powercap_init(void)
{
	int result;

	result = seed_constraint_attributes();
	if (result)
		return result;

	return class_register(&powercap_class);
}

fs_initcall(powercap_init);

MODULE_DESCRIPTION("PowerCap sysfs Driver");
MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
f6cc69f1	1	// SPDX-License-Identifier: GPL-2.0-only
75d2364e SP	2	/*
	3	* Power capping class
	4	* Copyright (c) 2013, Intel Corporation.
75d2364e SP	5	*/
	6
	7	#include <linux/module.h>
	8	#include <linux/device.h>
	9	#include <linux/err.h>
	10	#include <linux/slab.h>
	11	#include <linux/powercap.h>
	12
	13	#define to_powercap_zone(n) container_of(n, struct powercap_zone, dev)
	14	#define to_powercap_control_type(n) \
	15	container_of(n, struct powercap_control_type, dev)
	16
	17	/* Power zone show function */
	18	#define define_power_zone_show(_attr) \
	19	static ssize_t _attr##_show(struct device *dev, \
	20	struct device_attribute *dev_attr,\
	21	char *buf) \
	22	{ \
	23	u64 value; \
	24	ssize_t len = -EINVAL; \
	25	struct powercap_zone *power_zone = to_powercap_zone(dev); \
	26	\
	27	if (power_zone->ops->get_##_attr) { \
	28	if (!power_zone->ops->get_##_attr(power_zone, &value)) \
	29	len = sprintf(buf, "%lld\n", value); \
	30	} \
	31	\
	32	return len; \
	33	}
	34
	35	/* The only meaningful input is 0 (reset), others are silently ignored */
	36	#define define_power_zone_store(_attr) \
	37	static ssize_t _attr##_store(struct device *dev,\
	38	struct device_attribute *dev_attr, \
	39	const char *buf, size_t count) \
	40	{ \
	41	int err; \
	42	struct powercap_zone *power_zone = to_powercap_zone(dev); \
	43	u64 value; \
	44	\
	45	err = kstrtoull(buf, 10, &value); \
	46	if (err) \
	47	return -EINVAL; \
	48	if (value) \
	49	return count; \
	50	if (power_zone->ops->reset_##_attr) { \
	51	if (!power_zone->ops->reset_##_attr(power_zone)) \
	52	return count; \
	53	} \
	54	\
	55	return -EINVAL; \
	56	}
	57
	58	/* Power zone constraint show function */
	59	#define define_power_zone_constraint_show(_attr) \
	60	static ssize_t show_constraint_##_attr(struct device *dev, \
	61	struct device_attribute *dev_attr,\
	62	char *buf) \
	63	{ \
	64	u64 value; \
	65	ssize_t len = -ENODATA; \
	66	struct powercap_zone *power_zone = to_powercap_zone(dev); \
	67	int id; \
	68	struct powercap_zone_constraint *pconst;\
69	\
70	if (!sscanf(dev_attr->attr.name, "constraint_%d_", &id)) \
71	return -EINVAL; \
72	if (id >= power_zone->const_id_cnt) \
73	return -EINVAL; \
74	pconst = &power_zone->constraints[id]; \
75	if (pconst && pconst->ops && pconst->ops->get_##_attr) { \
76	if (!pconst->ops->get_##_attr(power_zone, id, &value)) \
77	len = sprintf(buf, "%lld\n", value); \
78	} \
79	\
80	return len; \
81	}
82
83	/* Power zone constraint store function */
84	#define define_power_zone_constraint_store(_attr) \
85	static ssize_t store_constraint_##_attr(struct device *dev,\
86	struct device_attribute *dev_attr, \
87	const char *buf, size_t count) \
88	{ \
89	int err; \
90	u64 value; \
91	struct powercap_zone *power_zone = to_powercap_zone(dev); \
92	int id; \
93	struct powercap_zone_constraint *pconst;\
94	\
95	if (!sscanf(dev_attr->attr.name, "constraint_%d_", &id)) \
96	return -EINVAL; \
97	if (id >= power_zone->const_id_cnt) \
98	return -EINVAL; \
99	pconst = &power_zone->constraints[id]; \
100	err = kstrtoull(buf, 10, &value); \
101	if (err) \
102	return -EINVAL; \
103	if (pconst && pconst->ops && pconst->ops->set_##_attr) { \
104	if (!pconst->ops->set_##_attr(power_zone, id, value)) \
105	return count; \
106	} \
107	\
108	return -ENODATA; \
109	}
110
111	/* Power zone information callbacks */
112	define_power_zone_show(power_uw);
113	define_power_zone_show(max_power_range_uw);
114	define_power_zone_show(energy_uj);
115	define_power_zone_store(energy_uj);
116	define_power_zone_show(max_energy_range_uj);
117
118	/* Power zone attributes */
119	static DEVICE_ATTR_RO(max_power_range_uw);
120	static DEVICE_ATTR_RO(power_uw);
121	static DEVICE_ATTR_RO(max_energy_range_uj);
122	static DEVICE_ATTR_RW(energy_uj);
123
124	/* Power zone constraint attributes callbacks */
125	define_power_zone_constraint_show(power_limit_uw);
126	define_power_zone_constraint_store(power_limit_uw);
127	define_power_zone_constraint_show(time_window_us);
128	define_power_zone_constraint_store(time_window_us);
129	define_power_zone_constraint_show(max_power_uw);
130	define_power_zone_constraint_show(min_power_uw);
131	define_power_zone_constraint_show(max_time_window_us);
132	define_power_zone_constraint_show(min_time_window_us);
133
134	/* For one time seeding of constraint device attributes */
135	struct powercap_constraint_attr {
136	struct device_attribute power_limit_attr;
137	struct device_attribute time_window_attr;
138	struct device_attribute max_power_attr;
139	struct device_attribute min_power_attr;
140	struct device_attribute max_time_window_attr;
141	struct device_attribute min_time_window_attr;
142	struct device_attribute name_attr;
143	};
144
145	static struct powercap_constraint_attr
146	constraint_attrs[MAX_CONSTRAINTS_PER_ZONE];
147
148	/* A list of powercap control_types */
149	static LIST_HEAD(powercap_cntrl_list);
150	/* Mutex to protect list of powercap control_types */
151	static DEFINE_MUTEX(powercap_cntrl_list_lock);
152
153	#define POWERCAP_CONSTRAINT_NAME_LEN 30 /* Some limit to avoid overflow */
154	static ssize_t show_constraint_name(struct device *dev,
155	struct device_attribute *dev_attr,
156	char *buf)
157	{
158	const char *name;
159	struct powercap_zone *power_zone = to_powercap_zone(dev);
160	int id;
161	ssize_t len = -ENODATA;
162	struct powercap_zone_constraint *pconst;
163
164	if (!sscanf(dev_attr->attr.name, "constraint_%d_", &id))
165	return -EINVAL;
166	if (id >= power_zone->const_id_cnt)
167	return -EINVAL;
168	pconst = &power_zone->constraints[id];
169
170	if (pconst && pconst->ops && pconst->ops->get_name) {
171	name = pconst->ops->get_name(power_zone, id);
172	if (name) {
173	snprintf(buf, POWERCAP_CONSTRAINT_NAME_LEN,
174	"%s\n", name);
175	buf[POWERCAP_CONSTRAINT_NAME_LEN] = '\0';
176	len = strlen(buf);
177	}
178	}
179
180	return len;
181	}
182
183	static int create_constraint_attribute(int id, const char *name,
184	int mode,
185	struct device_attribute *dev_attr,
186	ssize_t (show)(struct device ,
187	struct device_attribute , char ),
188	ssize_t (store)(struct device ,
189	struct device_attribute *,
190	const char *, size_t)
191	)
192	{
193
194	dev_attr->attr.name = kasprintf(GFP_KERNEL, "constraint_%d_%s",
195	id, name);
196	if (!dev_attr->attr.name)
197	return -ENOMEM;
198	dev_attr->attr.mode = mode;
199	dev_attr->show = show;
200	dev_attr->store = store;
201
202	return 0;
203	}
204
205	static void free_constraint_attributes(void)
206	{
207	int i;
208
209	for (i = 0; i < MAX_CONSTRAINTS_PER_ZONE; ++i) {
210	kfree(constraint_attrs[i].power_limit_attr.attr.name);
211	kfree(constraint_attrs[i].time_window_attr.attr.name);
212	kfree(constraint_attrs[i].name_attr.attr.name);
213	kfree(constraint_attrs[i].max_power_attr.attr.name);
214	kfree(constraint_attrs[i].min_power_attr.attr.name);
215	kfree(constraint_attrs[i].max_time_window_attr.attr.name);
216	kfree(constraint_attrs[i].min_time_window_attr.attr.name);
217	}
218	}
219
220	static int seed_constraint_attributes(void)
221	{
222	int i;
223	int ret;
224
225	for (i = 0; i < MAX_CONSTRAINTS_PER_ZONE; ++i) {
226	ret = create_constraint_attribute(i, "power_limit_uw",
227	S_IWUSR \| S_IRUGO,
228	&constraint_attrs[i].power_limit_attr,
229	show_constraint_power_limit_uw,
230	store_constraint_power_limit_uw);
231	if (ret)
232	goto err_alloc;
233	ret = create_constraint_attribute(i, "time_window_us",
234	S_IWUSR \| S_IRUGO,
235	&constraint_attrs[i].time_window_attr,
236	show_constraint_time_window_us,
237	store_constraint_time_window_us);
238	if (ret)
239	goto err_alloc;
240	ret = create_constraint_attribute(i, "name", S_IRUGO,
241	&constraint_attrs[i].name_attr,
242	show_constraint_name,
243	NULL);
244	if (ret)
245	goto err_alloc;
246	ret = create_constraint_attribute(i, "max_power_uw", S_IRUGO,
247	&constraint_attrs[i].max_power_attr,
248	show_constraint_max_power_uw,
249	NULL);
250	if (ret)
251	goto err_alloc;
252	ret = create_constraint_attribute(i, "min_power_uw", S_IRUGO,
253	&constraint_attrs[i].min_power_attr,
254	show_constraint_min_power_uw,
255	NULL);
256	if (ret)
257	goto err_alloc;
258	ret = create_constraint_attribute(i, "max_time_window_us",
259	S_IRUGO,
260	&constraint_attrs[i].max_time_window_attr,
261	show_constraint_max_time_window_us,
262	NULL);
263	if (ret)
264	goto err_alloc;
265	ret = create_constraint_attribute(i, "min_time_window_us",
266	S_IRUGO,
267	&constraint_attrs[i].min_time_window_attr,
268	show_constraint_min_time_window_us,
269	NULL);
270	if (ret)
271	goto err_alloc;
272
273	}
274
275	return 0;
276
277	err_alloc:
278	free_constraint_attributes();
279
280	return ret;
281	}
282
283	static int create_constraints(struct powercap_zone *power_zone,
600c395b JL	284	int nr_constraints,
600c395b JL	285	const struct powercap_zone_constraint_ops *const_ops)
75d2364e SP	286	{
	287	int i;
	288	int ret = 0;
	289	int count;
	290	struct powercap_zone_constraint *pconst;
	291
	292	if (!power_zone \|\| !const_ops \|\| !const_ops->get_power_limit_uw \|\|
	293	!const_ops->set_power_limit_uw \|\|
	294	!const_ops->get_time_window_us \|\|
	295	!const_ops->set_time_window_us)
	296	return -EINVAL;
	297
	298	count = power_zone->zone_attr_count;
	299	for (i = 0; i < nr_constraints; ++i) {
	300	pconst = &power_zone->constraints[i];
	301	pconst->ops = const_ops;
	302	pconst->id = power_zone->const_id_cnt;
	303	power_zone->const_id_cnt++;
	304	power_zone->zone_dev_attrs[count++] =
	305	&constraint_attrs[i].power_limit_attr.attr;
	306	power_zone->zone_dev_attrs[count++] =
	307	&constraint_attrs[i].time_window_attr.attr;
	308	if (pconst->ops->get_name)
	309	power_zone->zone_dev_attrs[count++] =
	310	&constraint_attrs[i].name_attr.attr;
	311	if (pconst->ops->get_max_power_uw)
	312	power_zone->zone_dev_attrs[count++] =
	313	&constraint_attrs[i].max_power_attr.attr;
	314	if (pconst->ops->get_min_power_uw)
	315	power_zone->zone_dev_attrs[count++] =
	316	&constraint_attrs[i].min_power_attr.attr;
	317	if (pconst->ops->get_max_time_window_us)
	318	power_zone->zone_dev_attrs[count++] =
	319	&constraint_attrs[i].max_time_window_attr.attr;
	320	if (pconst->ops->get_min_time_window_us)
	321	power_zone->zone_dev_attrs[count++] =
	322	&constraint_attrs[i].min_time_window_attr.attr;
	323	}
	324	power_zone->zone_attr_count = count;
	325
	326	return ret;
	327	}
	328
	329	static bool control_type_valid(void *control_type)
	330	{
	331	struct powercap_control_type *pos = NULL;
	332	bool found = false;
	333
	334	mutex_lock(&powercap_cntrl_list_lock);
	335
	336	list_for_each_entry(pos, &powercap_cntrl_list, node) {
	337	if (pos == control_type) {
	338	found = true;
	339	break;
	340	}
	341	}
	342	mutex_unlock(&powercap_cntrl_list_lock);
	343
	344	return found;
	345	}
	346
	347	static ssize_t name_show(struct device *dev,
	348	struct device_attribute *attr,
	349	char *buf)
350	{
351	struct powercap_zone *power_zone = to_powercap_zone(dev);
352
353	return sprintf(buf, "%s\n", power_zone->name);
354	}
355
356	static DEVICE_ATTR_RO(name);
357
358	/* Create zone and attributes in sysfs */
359	static void create_power_zone_common_attributes(
360	struct powercap_zone *power_zone)
361	{
362	int count = 0;
363
364	power_zone->zone_dev_attrs[count++] = &dev_attr_name.attr;
365	if (power_zone->ops->get_max_energy_range_uj)
366	power_zone->zone_dev_attrs[count++] =
367	&dev_attr_max_energy_range_uj.attr;
95677a9a SP	368	if (power_zone->ops->get_energy_uj) {
	369	if (power_zone->ops->reset_energy_uj)
	370	dev_attr_energy_uj.attr.mode = S_IWUSR \| S_IRUGO;
	371	else
	372	dev_attr_energy_uj.attr.mode = S_IRUGO;
75d2364e SP	373	power_zone->zone_dev_attrs[count++] =
75d2364e SP	374	&dev_attr_energy_uj.attr;
95677a9a	375	}
75d2364e SP	376	if (power_zone->ops->get_power_uw)
	377	power_zone->zone_dev_attrs[count++] =
	378	&dev_attr_power_uw.attr;
	379	if (power_zone->ops->get_max_power_range_uw)
	380	power_zone->zone_dev_attrs[count++] =
	381	&dev_attr_max_power_range_uw.attr;
	382	power_zone->zone_dev_attrs[count] = NULL;
	383	power_zone->zone_attr_count = count;
	384	}
	385
	386	static void powercap_release(struct device *dev)
	387	{
	388	bool allocated;
	389
	390	if (dev->parent) {
	391	struct powercap_zone *power_zone = to_powercap_zone(dev);
	392
	393	/* Store flag as the release() may free memory */
	394	allocated = power_zone->allocated;
	395	/* Remove id from parent idr struct */
	396	idr_remove(power_zone->parent_idr, power_zone->id);
	397	/* Destroy idrs allocated for this zone */
	398	idr_destroy(&power_zone->idr);
	399	kfree(power_zone->name);
	400	kfree(power_zone->zone_dev_attrs);
	401	kfree(power_zone->constraints);
	402	if (power_zone->ops->release)
	403	power_zone->ops->release(power_zone);
	404	if (allocated)
	405	kfree(power_zone);
	406	} else {
	407	struct powercap_control_type *control_type =
	408	to_powercap_control_type(dev);
	409
	410	/* Store flag as the release() may free memory */
	411	allocated = control_type->allocated;
	412	idr_destroy(&control_type->idr);
	413	mutex_destroy(&control_type->lock);
	414	if (control_type->ops && control_type->ops->release)
	415	control_type->ops->release(control_type);
	416	if (allocated)
	417	kfree(control_type);
	418	}
	419	}
	420
	421	static ssize_t enabled_show(struct device *dev,
	422	struct device_attribute *attr,
	423	char *buf)
	424	{
	425	bool mode = true;
	426
	427	/* Default is enabled */
	428	if (dev->parent) {
	429	struct powercap_zone *power_zone = to_powercap_zone(dev);
	430	if (power_zone->ops->get_enable)
	431	if (power_zone->ops->get_enable(power_zone, &mode))
	432	mode = false;
	433	} else {
	434	struct powercap_control_type *control_type =
	435	to_powercap_control_type(dev);
	436	if (control_type->ops && control_type->ops->get_enable)
	437	if (control_type->ops->get_enable(control_type, &mode))
	438	mode = false;
	439	}
440
441	return sprintf(buf, "%d\n", mode);
442	}
443
444	static ssize_t enabled_store(struct device *dev,
445	struct device_attribute *attr,
446	const char *buf, size_t len)
447	{
448	bool mode;
449
450	if (strtobool(buf, &mode))
451	return -EINVAL;
452	if (dev->parent) {
453	struct powercap_zone *power_zone = to_powercap_zone(dev);
454	if (power_zone->ops->set_enable)
455	if (!power_zone->ops->set_enable(power_zone, mode))
456	return len;
457	} else {
458	struct powercap_control_type *control_type =
459	to_powercap_control_type(dev);
460	if (control_type->ops && control_type->ops->set_enable)
461	if (!control_type->ops->set_enable(control_type, mode))
462	return len;
463	}
464
465	return -ENOSYS;
466	}
467
9e3410b7 TR	468	static DEVICE_ATTR_RW(enabled);
	469
	470	static struct attribute *powercap_attrs[] = {
	471	&dev_attr_enabled.attr,
	472	NULL,
75d2364e	473	};
9e3410b7	474	ATTRIBUTE_GROUPS(powercap);
75d2364e SP	475
	476	static struct class powercap_class = {
	477	.name = "powercap",
	478	.dev_release = powercap_release,
9e3410b7	479	.dev_groups = powercap_groups,
75d2364e SP	480	};
	481
	482	struct powercap_zone *powercap_register_zone(
600c395b JL	483	struct powercap_zone *power_zone,
	484	struct powercap_control_type *control_type,
	485	const char *name,
	486	struct powercap_zone *parent,
	487	const struct powercap_zone_ops *ops,
	488	int nr_constraints,
	489	const struct powercap_zone_constraint_ops *const_ops)
75d2364e SP	490	{
	491	int result;
	492	int nr_attrs;
	493
	494	if (!name \|\| !control_type \|\| !ops \|\|
	495	nr_constraints > MAX_CONSTRAINTS_PER_ZONE \|\|
	496	(!ops->get_energy_uj && !ops->get_power_uw) \|\|
	497	!control_type_valid(control_type))
	498	return ERR_PTR(-EINVAL);
	499
	500	if (power_zone) {
	501	if (!ops->release)
	502	return ERR_PTR(-EINVAL);
	503	memset(power_zone, 0, sizeof(*power_zone));
	504	} else {
	505	power_zone = kzalloc(sizeof(*power_zone), GFP_KERNEL);
	506	if (!power_zone)
	507	return ERR_PTR(-ENOMEM);
	508	power_zone->allocated = true;
	509	}
	510	power_zone->ops = ops;
	511	power_zone->control_type_inst = control_type;
	512	if (!parent) {
	513	power_zone->dev.parent = &control_type->dev;
	514	power_zone->parent_idr = &control_type->idr;
	515	} else {
	516	power_zone->dev.parent = &parent->dev;
	517	power_zone->parent_idr = &parent->idr;
	518	}
	519	power_zone->dev.class = &powercap_class;
	520
	521	mutex_lock(&control_type->lock);
	522	/* Using idr to get the unique id */
	523	result = idr_alloc(power_zone->parent_idr, NULL, 0, 0, GFP_KERNEL);
	524	if (result < 0)
	525	goto err_idr_alloc;
	526
	527	power_zone->id = result;
	528	idr_init(&power_zone->idr);
216c4e9d	529	result = -ENOMEM;
75d2364e SP	530	power_zone->name = kstrdup(name, GFP_KERNEL);
	531	if (!power_zone->name)
	532	goto err_name_alloc;
	533	dev_set_name(&power_zone->dev, "%s:%x",
	534	dev_name(power_zone->dev.parent),
	535	power_zone->id);
6396bb22 KC	536	power_zone->constraints = kcalloc(nr_constraints,
	537	sizeof(*power_zone->constraints),
	538	GFP_KERNEL);
75d2364e SP	539	if (!power_zone->constraints)
	540	goto err_const_alloc;
	541
	542	nr_attrs = nr_constraints * POWERCAP_CONSTRAINTS_ATTRS +
	543	POWERCAP_ZONE_MAX_ATTRS + 1;
6396bb22 KC	544	power_zone->zone_dev_attrs = kcalloc(nr_attrs, sizeof(void *),
6396bb22 KC	545	GFP_KERNEL);
75d2364e SP	546	if (!power_zone->zone_dev_attrs)
	547	goto err_attr_alloc;
	548	create_power_zone_common_attributes(power_zone);
	549	result = create_constraints(power_zone, nr_constraints, const_ops);
	550	if (result)
	551	goto err_dev_ret;
	552
	553	power_zone->zone_dev_attrs[power_zone->zone_attr_count] = NULL;
	554	power_zone->dev_zone_attr_group.attrs = power_zone->zone_dev_attrs;
	555	power_zone->dev_attr_groups[0] = &power_zone->dev_zone_attr_group;
	556	power_zone->dev_attr_groups[1] = NULL;
	557	power_zone->dev.groups = power_zone->dev_attr_groups;
	558	result = device_register(&power_zone->dev);
	559	if (result)
	560	goto err_dev_ret;
	561
	562	control_type->nr_zones++;
	563	mutex_unlock(&control_type->lock);
	564
	565	return power_zone;
	566
	567	err_dev_ret:
	568	kfree(power_zone->zone_dev_attrs);
	569	err_attr_alloc:
	570	kfree(power_zone->constraints);
	571	err_const_alloc:
	572	kfree(power_zone->name);
	573	err_name_alloc:
	574	idr_remove(power_zone->parent_idr, power_zone->id);
	575	err_idr_alloc:
	576	if (power_zone->allocated)
	577	kfree(power_zone);
	578	mutex_unlock(&control_type->lock);
	579
	580	return ERR_PTR(result);
	581	}
	582	EXPORT_SYMBOL_GPL(powercap_register_zone);
	583
	584	int powercap_unregister_zone(struct powercap_control_type *control_type,
	585	struct powercap_zone *power_zone)
	586	{
	587	if (!power_zone \|\| !control_type)
	588	return -EINVAL;
	589
	590	mutex_lock(&control_type->lock);
	591	control_type->nr_zones--;
	592	mutex_unlock(&control_type->lock);
	593
	594	device_unregister(&power_zone->dev);
	595
	596	return 0;
	597	}
	598	EXPORT_SYMBOL_GPL(powercap_unregister_zone);
	599
	600	struct powercap_control_type *powercap_register_control_type(
	601	struct powercap_control_type *control_type,
	602	const char *name,
	603	const struct powercap_control_type_ops *ops)
	604	{
	605	int result;
	606
	607	if (!name)
	608	return ERR_PTR(-EINVAL);
	609	if (control_type) {
610	if (!ops \|\| !ops->release)
611	return ERR_PTR(-EINVAL);
612	memset(control_type, 0, sizeof(*control_type));
613	} else {
614	control_type = kzalloc(sizeof(*control_type), GFP_KERNEL);
615	if (!control_type)
616	return ERR_PTR(-ENOMEM);
617	control_type->allocated = true;
618	}
619	mutex_init(&control_type->lock);
620	control_type->ops = ops;
621	INIT_LIST_HEAD(&control_type->node);
622	control_type->dev.class = &powercap_class;
08ff4cbe	623	dev_set_name(&control_type->dev, "%s", name);
75d2364e SP	624	result = device_register(&control_type->dev);
	625	if (result) {
	626	if (control_type->allocated)
	627	kfree(control_type);
	628	return ERR_PTR(result);
	629	}
	630	idr_init(&control_type->idr);
	631
	632	mutex_lock(&powercap_cntrl_list_lock);
	633	list_add_tail(&control_type->node, &powercap_cntrl_list);
	634	mutex_unlock(&powercap_cntrl_list_lock);
	635
	636	return control_type;
	637	}
	638	EXPORT_SYMBOL_GPL(powercap_register_control_type);
	639
	640	int powercap_unregister_control_type(struct powercap_control_type *control_type)
	641	{
	642	struct powercap_control_type *pos = NULL;
	643
	644	if (control_type->nr_zones) {
	645	dev_err(&control_type->dev, "Zones of this type still not freed\n");
	646	return -EINVAL;
	647	}
	648	mutex_lock(&powercap_cntrl_list_lock);
	649	list_for_each_entry(pos, &powercap_cntrl_list, node) {
	650	if (pos == control_type) {
	651	list_del(&control_type->node);
	652	mutex_unlock(&powercap_cntrl_list_lock);
	653	device_unregister(&control_type->dev);
	654	return 0;
	655	}
	656	}
	657	mutex_unlock(&powercap_cntrl_list_lock);
	658
	659	return -ENODEV;
	660	}
	661	EXPORT_SYMBOL_GPL(powercap_unregister_control_type);
	662
	663	static int __init powercap_init(void)
	664	{
7f634489	665	int result;
75d2364e SP	666
	667	result = seed_constraint_attributes();
	668	if (result)
	669	return result;
	670
7f634489	671	return class_register(&powercap_class);
75d2364e SP	672	}
75d2364e SP	673
f76cb066	674	fs_initcall(powercap_init);
75d2364e SP	675
	676	MODULE_DESCRIPTION("PowerCap sysfs Driver");
	677	MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
	678	MODULE_LICENSE("GPL v2");