diff --git a/Documentation/hwmon/acpi_power_meter b/Documentation/hwmon/acpi_power_meter new file mode 100644 index 000000000000..c80399a00c50 --- /dev/null +++ b/Documentation/hwmon/acpi_power_meter @@ -0,0 +1,51 @@ +Kernel driver power_meter +========================= + +This driver talks to ACPI 4.0 power meters. + +Supported systems: + * Any recent system with ACPI 4.0. + Prefix: 'power_meter' + Datasheet: http://acpi.info/, section 10.4. + +Author: Darrick J. Wong + +Description +----------- + +This driver implements sensor reading support for the power meters exposed in +the ACPI 4.0 spec (Chapter 10.4). These devices have a simple set of +features--a power meter that returns average power use over a configurable +interval, an optional capping mechanism, and a couple of trip points. The +sysfs interface conforms with the specification outlined in the "Power" section +of Documentation/hwmon/sysfs-interface. + +Special Features +---------------- + +The power[1-*]_is_battery knob indicates if the power supply is a battery. +Both power[1-*]_average_{min,max} must be set before the trip points will work. +When both of them are set, an ACPI event will be broadcast on the ACPI netlink +socket and a poll notification will be sent to the appropriate +power[1-*]_average sysfs file. + +The power[1-*]_{model_number, serial_number, oem_info} fields display arbitrary +strings that ACPI provides with the meter. The measures/ directory contains +symlinks to the devices that this meter measures. + +Some computers have the ability to enforce a power cap in hardware. If this is +the case, the power[1-*]_cap and related sysfs files will appear. When the +average power consumption exceeds the cap, an ACPI event will be broadcast on +the netlink event socket and a poll notification will be sent to the +appropriate power[1-*]_alarm file to indicate that capping has begun, and the +hardware has taken action to reduce power consumption. Most likely this will +result in reduced performance. + +There are a few other ACPI notifications that can be sent by the firmware. In +all cases the ACPI event will be broadcast on the ACPI netlink event socket as +well as sent as a poll notification to a sysfs file. The events are as +follows: + +power[1-*]_cap will be notified if the firmware changes the power cap. +power[1-*]_interval will be notified if the firmware changes the averaging +interval. diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig index 7ec7d88c5999..2c1cab5642ff 100644 --- a/drivers/acpi/Kconfig +++ b/drivers/acpi/Kconfig @@ -82,6 +82,17 @@ config ACPI_PROCFS_POWER Say N to delete power /proc/acpi/ directories that have moved to /sys/ +config ACPI_POWER_METER + tristate "ACPI 4.0 power meter" + depends on HWMON + help + This driver exposes ACPI 4.0 power meters as hardware monitoring + devices. Say Y (or M) if you have a computer with ACPI 4.0 firmware + and a power meter. + + To compile this driver as a module, choose M here: + the module will be called power-meter. + config ACPI_SYSFS_POWER bool "Future power /sys interface" select POWER_SUPPLY diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile index 03a985be3fe3..82cd49dc603b 100644 --- a/drivers/acpi/Makefile +++ b/drivers/acpi/Makefile @@ -56,6 +56,7 @@ obj-$(CONFIG_ACPI_HOTPLUG_MEMORY) += acpi_memhotplug.o obj-$(CONFIG_ACPI_BATTERY) += battery.o obj-$(CONFIG_ACPI_SBS) += sbshc.o obj-$(CONFIG_ACPI_SBS) += sbs.o +obj-$(CONFIG_ACPI_POWER_METER) += power_meter.o # processor has its own "processor." module_param namespace processor-y := processor_core.o processor_throttling.o diff --git a/drivers/acpi/power_meter.c b/drivers/acpi/power_meter.c new file mode 100644 index 000000000000..e6bfd77986b8 --- /dev/null +++ b/drivers/acpi/power_meter.c @@ -0,0 +1,1018 @@ +/* + * A hwmon driver for ACPI 4.0 power meters + * Copyright (C) 2009 IBM + * + * Author: Darrick J. Wong + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define ACPI_POWER_METER_NAME "power_meter" +ACPI_MODULE_NAME(ACPI_POWER_METER_NAME); +#define ACPI_POWER_METER_DEVICE_NAME "Power Meter" +#define ACPI_POWER_METER_CLASS "power_meter_resource" + +#define NUM_SENSORS 17 + +#define POWER_METER_CAN_MEASURE (1 << 0) +#define POWER_METER_CAN_TRIP (1 << 1) +#define POWER_METER_CAN_CAP (1 << 2) +#define POWER_METER_CAN_NOTIFY (1 << 3) +#define POWER_METER_IS_BATTERY (1 << 8) +#define UNKNOWN_HYSTERESIS 0xFFFFFFFF + +#define METER_NOTIFY_CONFIG 0x80 +#define METER_NOTIFY_TRIP 0x81 +#define METER_NOTIFY_CAP 0x82 +#define METER_NOTIFY_CAPPING 0x83 +#define METER_NOTIFY_INTERVAL 0x84 + +#define POWER_AVERAGE_NAME "power1_average" +#define POWER_CAP_NAME "power1_cap" +#define POWER_AVG_INTERVAL_NAME "power1_average_interval" +#define POWER_ALARM_NAME "power1_alarm" + +static int cap_in_hardware; +static int force_cap_on; + +static int can_cap_in_hardware(void) +{ + return force_cap_on || cap_in_hardware; +} + +static struct acpi_device_id power_meter_ids[] = { + {"ACPI000D", 0}, + {"", 0}, +}; +MODULE_DEVICE_TABLE(acpi, power_meter_ids); + +struct acpi_power_meter_capabilities { + acpi_integer flags; + acpi_integer units; + acpi_integer type; + acpi_integer accuracy; + acpi_integer sampling_time; + acpi_integer min_avg_interval; + acpi_integer max_avg_interval; + acpi_integer hysteresis; + acpi_integer configurable_cap; + acpi_integer min_cap; + acpi_integer max_cap; +}; + +struct acpi_power_meter_resource { + struct acpi_device *acpi_dev; + acpi_bus_id name; + struct mutex lock; + struct device *hwmon_dev; + struct acpi_power_meter_capabilities caps; + acpi_string model_number; + acpi_string serial_number; + acpi_string oem_info; + acpi_integer power; + acpi_integer cap; + acpi_integer avg_interval; + int sensors_valid; + unsigned long sensors_last_updated; + struct sensor_device_attribute sensors[NUM_SENSORS]; + int num_sensors; + int trip[2]; + int num_domain_devices; + struct acpi_device **domain_devices; + struct kobject *holders_dir; +}; + +struct ro_sensor_template { + char *label; + ssize_t (*show)(struct device *dev, + struct device_attribute *devattr, + char *buf); + int index; +}; + +struct rw_sensor_template { + char *label; + ssize_t (*show)(struct device *dev, + struct device_attribute *devattr, + char *buf); + ssize_t (*set)(struct device *dev, + struct device_attribute *devattr, + const char *buf, size_t count); + int index; +}; + +/* Averaging interval */ +static int update_avg_interval(struct acpi_power_meter_resource *resource) +{ + unsigned long long data; + acpi_status status; + + status = acpi_evaluate_integer(resource->acpi_dev->handle, "_GAI", + NULL, &data); + if (ACPI_FAILURE(status)) { + ACPI_EXCEPTION((AE_INFO, status, "Evaluating _GAI")); + return -ENODEV; + } + + resource->avg_interval = data; + return 0; +} + +static ssize_t show_avg_interval(struct device *dev, + struct device_attribute *devattr, + char *buf) +{ + struct acpi_device *acpi_dev = to_acpi_device(dev); + struct acpi_power_meter_resource *resource = acpi_dev->driver_data; + + mutex_lock(&resource->lock); + update_avg_interval(resource); + mutex_unlock(&resource->lock); + + return sprintf(buf, "%llu\n", resource->avg_interval); +} + +static ssize_t set_avg_interval(struct device *dev, + struct device_attribute *devattr, + const char *buf, size_t count) +{ + struct acpi_device *acpi_dev = to_acpi_device(dev); + struct acpi_power_meter_resource *resource = acpi_dev->driver_data; + union acpi_object arg0 = { ACPI_TYPE_INTEGER }; + struct acpi_object_list args = { 1, &arg0 }; + int res; + unsigned long temp; + unsigned long long data; + acpi_status status; + + res = strict_strtoul(buf, 10, &temp); + if (res) + return res; + + if (temp > resource->caps.max_avg_interval || + temp < resource->caps.min_avg_interval) + return -EINVAL; + arg0.integer.value = temp; + + mutex_lock(&resource->lock); + status = acpi_evaluate_integer(resource->acpi_dev->handle, "_PAI", + &args, &data); + if (!ACPI_FAILURE(status)) + resource->avg_interval = temp; + mutex_unlock(&resource->lock); + + if (ACPI_FAILURE(status)) { + ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PAI")); + return -EINVAL; + } + + /* _PAI returns 0 on success, nonzero otherwise */ + if (data) + return -EINVAL; + + return count; +} + +/* Cap functions */ +static int update_cap(struct acpi_power_meter_resource *resource) +{ + unsigned long long data; + acpi_status status; + + status = acpi_evaluate_integer(resource->acpi_dev->handle, "_GHL", + NULL, &data); + if (ACPI_FAILURE(status)) { + ACPI_EXCEPTION((AE_INFO, status, "Evaluating _GHL")); + return -ENODEV; + } + + resource->cap = data; + return 0; +} + +static ssize_t show_cap(struct device *dev, + struct device_attribute *devattr, + char *buf) +{ + struct acpi_device *acpi_dev = to_acpi_device(dev); + struct acpi_power_meter_resource *resource = acpi_dev->driver_data; + + mutex_lock(&resource->lock); + update_cap(resource); + mutex_unlock(&resource->lock); + + return sprintf(buf, "%llu\n", resource->cap * 1000); +} + +static ssize_t set_cap(struct device *dev, struct device_attribute *devattr, + const char *buf, size_t count) +{ + struct acpi_device *acpi_dev = to_acpi_device(dev); + struct acpi_power_meter_resource *resource = acpi_dev->driver_data; + union acpi_object arg0 = { ACPI_TYPE_INTEGER }; + struct acpi_object_list args = { 1, &arg0 }; + int res; + unsigned long temp; + unsigned long long data; + acpi_status status; + + res = strict_strtoul(buf, 10, &temp); + if (res) + return res; + + temp /= 1000; + if (temp > resource->caps.max_cap || temp < resource->caps.min_cap) + return -EINVAL; + arg0.integer.value = temp; + + mutex_lock(&resource->lock); + status = acpi_evaluate_integer(resource->acpi_dev->handle, "_SHL", + &args, &data); + if (!ACPI_FAILURE(status)) + resource->cap = temp; + mutex_unlock(&resource->lock); + + if (ACPI_FAILURE(status)) { + ACPI_EXCEPTION((AE_INFO, status, "Evaluating _SHL")); + return -EINVAL; + } + + /* _SHL returns 0 on success, nonzero otherwise */ + if (data) + return -EINVAL; + + return count; +} + +/* Power meter trip points */ +static int set_acpi_trip(struct acpi_power_meter_resource *resource) +{ + union acpi_object arg_objs[] = { + {ACPI_TYPE_INTEGER}, + {ACPI_TYPE_INTEGER} + }; + struct acpi_object_list args = { 2, arg_objs }; + unsigned long long data; + acpi_status status; + + /* Both trip levels must be set */ + if (resource->trip[0] < 0 || resource->trip[1] < 0) + return 0; + + /* This driver stores min, max; ACPI wants max, min. */ + arg_objs[0].integer.value = resource->trip[1]; + arg_objs[1].integer.value = resource->trip[0]; + + status = acpi_evaluate_integer(resource->acpi_dev->handle, "_PTP", + &args, &data); + if (ACPI_FAILURE(status)) { + ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PTP")); + return -EINVAL; + } + + return data; +} + +static ssize_t set_trip(struct device *dev, struct device_attribute *devattr, + const char *buf, size_t count) +{ + struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); + struct acpi_device *acpi_dev = to_acpi_device(dev); + struct acpi_power_meter_resource *resource = acpi_dev->driver_data; + int res; + unsigned long temp; + + res = strict_strtoul(buf, 10, &temp); + if (res) + return res; + + temp /= 1000; + if (temp < 0) + return -EINVAL; + + mutex_lock(&resource->lock); + resource->trip[attr->index - 7] = temp; + res = set_acpi_trip(resource); + mutex_unlock(&resource->lock); + + if (res) + return res; + + return count; +} + +/* Power meter */ +static int update_meter(struct acpi_power_meter_resource *resource) +{ + unsigned long long data; + acpi_status status; + unsigned long local_jiffies = jiffies; + + if (time_before(local_jiffies, resource->sensors_last_updated + + msecs_to_jiffies(resource->caps.sampling_time)) && + resource->sensors_valid) + return 0; + + status = acpi_evaluate_integer(resource->acpi_dev->handle, "_PMM", + NULL, &data); + if (ACPI_FAILURE(status)) { + ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PMM")); + return -ENODEV; + } + + resource->power = data; + resource->sensors_valid = 1; + resource->sensors_last_updated = jiffies; + return 0; +} + +static ssize_t show_power(struct device *dev, + struct device_attribute *devattr, + char *buf) +{ + struct acpi_device *acpi_dev = to_acpi_device(dev); + struct acpi_power_meter_resource *resource = acpi_dev->driver_data; + + mutex_lock(&resource->lock); + update_meter(resource); + mutex_unlock(&resource->lock); + + return sprintf(buf, "%llu\n", resource->power * 1000); +} + +/* Miscellaneous */ +static ssize_t show_str(struct device *dev, + struct device_attribute *devattr, + char *buf) +{ + struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); + struct acpi_device *acpi_dev = to_acpi_device(dev); + struct acpi_power_meter_resource *resource = acpi_dev->driver_data; + acpi_string val; + + switch (attr->index) { + case 0: + val = resource->model_number; + break; + case 1: + val = resource->serial_number; + break; + case 2: + val = resource->oem_info; + break; + default: + BUG(); + } + + return sprintf(buf, "%s\n", val); +} + +static ssize_t show_val(struct device *dev, + struct device_attribute *devattr, + char *buf) +{ + struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); + struct acpi_device *acpi_dev = to_acpi_device(dev); + struct acpi_power_meter_resource *resource = acpi_dev->driver_data; + acpi_integer val = 0; + + switch (attr->index) { + case 0: + val = resource->caps.min_avg_interval; + break; + case 1: + val = resource->caps.max_avg_interval; + break; + case 2: + val = resource->caps.min_cap * 1000; + break; + case 3: + val = resource->caps.max_cap * 1000; + break; + case 4: + if (resource->caps.hysteresis == UNKNOWN_HYSTERESIS) + return sprintf(buf, "unknown\n"); + + val = resource->caps.hysteresis * 1000; + break; + case 5: + if (resource->caps.flags & POWER_METER_IS_BATTERY) + val = 1; + else + val = 0; + break; + case 6: + if (resource->power > resource->cap) + val = 1; + else + val = 0; + break; + case 7: + case 8: + if (resource->trip[attr->index - 7] < 0) + return sprintf(buf, "unknown\n"); + + val = resource->trip[attr->index - 7] * 1000; + break; + default: + BUG(); + } + + return sprintf(buf, "%llu\n", val); +} + +static ssize_t show_accuracy(struct device *dev, + struct device_attribute *devattr, + char *buf) +{ + struct acpi_device *acpi_dev = to_acpi_device(dev); + struct acpi_power_meter_resource *resource = acpi_dev->driver_data; + unsigned int acc = resource->caps.accuracy; + + return sprintf(buf, "%u.%u%%\n", acc / 1000, acc % 1000); +} + +static ssize_t show_name(struct device *dev, + struct device_attribute *devattr, + char *buf) +{ + return sprintf(buf, "%s\n", ACPI_POWER_METER_NAME); +} + +/* Sensor descriptions. If you add a sensor, update NUM_SENSORS above! */ +static struct ro_sensor_template meter_ro_attrs[] = { +{POWER_AVERAGE_NAME, show_power, 0}, +{"power1_accuracy", show_accuracy, 0}, +{"power1_average_interval_min", show_val, 0}, +{"power1_average_interval_max", show_val, 1}, +{"power1_is_battery", show_val, 5}, +{NULL, NULL, 0}, +}; + +static struct rw_sensor_template meter_rw_attrs[] = { +{POWER_AVG_INTERVAL_NAME, show_avg_interval, set_avg_interval, 0}, +{NULL, NULL, NULL, 0}, +}; + +static struct ro_sensor_template misc_cap_attrs[] = { +{"power1_cap_min", show_val, 2}, +{"power1_cap_max", show_val, 3}, +{"power1_cap_hyst", show_val, 4}, +{POWER_ALARM_NAME, show_val, 6}, +{NULL, NULL, 0}, +}; + +static struct ro_sensor_template ro_cap_attrs[] = { +{POWER_CAP_NAME, show_cap, 0}, +{NULL, NULL, 0}, +}; + +static struct rw_sensor_template rw_cap_attrs[] = { +{POWER_CAP_NAME, show_cap, set_cap, 0}, +{NULL, NULL, NULL, 0}, +}; + +static struct rw_sensor_template trip_attrs[] = { +{"power1_average_min", show_val, set_trip, 7}, +{"power1_average_max", show_val, set_trip, 8}, +{NULL, NULL, NULL, 0}, +}; + +static struct ro_sensor_template misc_attrs[] = { +{"name", show_name, 0}, +{"power1_model_number", show_str, 0}, +{"power1_oem_info", show_str, 2}, +{"power1_serial_number", show_str, 1}, +{NULL, NULL, 0}, +}; + +/* Read power domain data */ +static void remove_domain_devices(struct acpi_power_meter_resource *resource) +{ + int i; + + if (!resource->num_domain_devices) + return; + + for (i = 0; i < resource->num_domain_devices; i++) { + struct acpi_device *obj = resource->domain_devices[i]; + if (!obj) + continue; + + sysfs_remove_link(resource->holders_dir, + kobject_name(&obj->dev.kobj)); + put_device(&obj->dev); + } + + kfree(resource->domain_devices); + kobject_put(resource->holders_dir); +} + +static int read_domain_devices(struct acpi_power_meter_resource *resource) +{ + int res = 0; + int i; + struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; + union acpi_object *pss; + acpi_status status; + + status = acpi_evaluate_object(resource->acpi_dev->handle, "_PMD", NULL, + &buffer); + if (ACPI_FAILURE(status)) { + ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PMD")); + return -ENODEV; + } + + pss = buffer.pointer; + if (!pss || + pss->type != ACPI_TYPE_PACKAGE) { + dev_err(&resource->acpi_dev->dev, ACPI_POWER_METER_NAME + "Invalid _PMD data\n"); + res = -EFAULT; + goto end; + } + + if (!pss->package.count) + goto end; + + resource->domain_devices = kzalloc(sizeof(struct acpi_device *) * + pss->package.count, GFP_KERNEL); + if (!resource->domain_devices) { + res = -ENOMEM; + goto end; + } + + resource->holders_dir = kobject_create_and_add("measures", + &resource->acpi_dev->dev.kobj); + if (!resource->holders_dir) { + res = -ENOMEM; + goto exit_free; + } + + resource->num_domain_devices = pss->package.count; + + for (i = 0; i < pss->package.count; i++) { + struct acpi_device *obj; + union acpi_object *element = &(pss->package.elements[i]); + + /* Refuse non-references */ + if (element->type != ACPI_TYPE_LOCAL_REFERENCE) + continue; + + /* Create a symlink to domain objects */ + resource->domain_devices[i] = NULL; + status = acpi_bus_get_device(element->reference.handle, + &resource->domain_devices[i]); + if (ACPI_FAILURE(status)) + continue; + + obj = resource->domain_devices[i]; + get_device(&obj->dev); + + res = sysfs_create_link(resource->holders_dir, &obj->dev.kobj, + kobject_name(&obj->dev.kobj)); + if (res) { + put_device(&obj->dev); + resource->domain_devices[i] = NULL; + } + } + + res = 0; + goto end; + +exit_free: + kfree(resource->domain_devices); +end: + kfree(buffer.pointer); + return res; +} + +/* Registration and deregistration */ +static int register_ro_attrs(struct acpi_power_meter_resource *resource, + struct ro_sensor_template *ro) +{ + struct device *dev = &resource->acpi_dev->dev; + struct sensor_device_attribute *sensors = + &resource->sensors[resource->num_sensors]; + int res = 0; + + while (ro->label) { + sensors->dev_attr.attr.name = ro->label; + sensors->dev_attr.attr.mode = S_IRUGO; + sensors->dev_attr.show = ro->show; + sensors->index = ro->index; + + res = device_create_file(dev, &sensors->dev_attr); + if (res) { + sensors->dev_attr.attr.name = NULL; + goto error; + } + sensors++; + resource->num_sensors++; + ro++; + } + +error: + return res; +} + +static int register_rw_attrs(struct acpi_power_meter_resource *resource, + struct rw_sensor_template *rw) +{ + struct device *dev = &resource->acpi_dev->dev; + struct sensor_device_attribute *sensors = + &resource->sensors[resource->num_sensors]; + int res = 0; + + while (rw->label) { + sensors->dev_attr.attr.name = rw->label; + sensors->dev_attr.attr.mode = S_IRUGO | S_IWUSR; + sensors->dev_attr.show = rw->show; + sensors->dev_attr.store = rw->set; + sensors->index = rw->index; + + res = device_create_file(dev, &sensors->dev_attr); + if (res) { + sensors->dev_attr.attr.name = NULL; + goto error; + } + sensors++; + resource->num_sensors++; + rw++; + } + +error: + return res; +} + +static void remove_attrs(struct acpi_power_meter_resource *resource) +{ + int i; + + for (i = 0; i < resource->num_sensors; i++) { + if (!resource->sensors[i].dev_attr.attr.name) + continue; + device_remove_file(&resource->acpi_dev->dev, + &resource->sensors[i].dev_attr); + } + + remove_domain_devices(resource); + + resource->num_sensors = 0; +} + +static int setup_attrs(struct acpi_power_meter_resource *resource) +{ + int res = 0; + + res = read_domain_devices(resource); + if (res) + return res; + + if (resource->caps.flags & POWER_METER_CAN_MEASURE) { + res = register_ro_attrs(resource, meter_ro_attrs); + if (res) + goto error; + res = register_rw_attrs(resource, meter_rw_attrs); + if (res) + goto error; + } + + if (resource->caps.flags & POWER_METER_CAN_CAP) { + if (!can_cap_in_hardware()) { + dev_err(&resource->acpi_dev->dev, + "Ignoring unsafe software power cap!\n"); + goto skip_unsafe_cap; + } + + if (resource->caps.configurable_cap) { + res = register_rw_attrs(resource, rw_cap_attrs); + if (res) + goto error; + } else { + res = register_ro_attrs(resource, ro_cap_attrs); + if (res) + goto error; + } + res = register_ro_attrs(resource, misc_cap_attrs); + if (res) + goto error; + } +skip_unsafe_cap: + + if (resource->caps.flags & POWER_METER_CAN_TRIP) { + res = register_rw_attrs(resource, trip_attrs); + if (res) + goto error; + } + + res = register_ro_attrs(resource, misc_attrs); + if (res) + goto error; + + return res; +error: + remove_domain_devices(resource); + remove_attrs(resource); + return res; +} + +static void free_capabilities(struct acpi_power_meter_resource *resource) +{ + acpi_string *str; + int i; + + str = &resource->model_number; + for (i = 0; i < 3; i++, str++) + kfree(*str); +} + +static int read_capabilities(struct acpi_power_meter_resource *resource) +{ + int res = 0; + int i; + struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; + struct acpi_buffer state = { 0, NULL }; + struct acpi_buffer format = { sizeof("NNNNNNNNNNN"), "NNNNNNNNNNN" }; + union acpi_object *pss; + acpi_string *str; + acpi_status status; + + status = acpi_evaluate_object(resource->acpi_dev->handle, "_PMC", NULL, + &buffer); + if (ACPI_FAILURE(status)) { + ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PMC")); + return -ENODEV; + } + + pss = buffer.pointer; + if (!pss || + pss->type != ACPI_TYPE_PACKAGE || + pss->package.count != 14) { + dev_err(&resource->acpi_dev->dev, ACPI_POWER_METER_NAME + "Invalid _PMC data\n"); + res = -EFAULT; + goto end; + } + + /* Grab all the integer data at once */ + state.length = sizeof(struct acpi_power_meter_capabilities); + state.pointer = &resource->caps; + + status = acpi_extract_package(pss, &format, &state); + if (ACPI_FAILURE(status)) { + ACPI_EXCEPTION((AE_INFO, status, "Invalid data")); + res = -EFAULT; + goto end; + } + + if (resource->caps.units) { + dev_err(&resource->acpi_dev->dev, ACPI_POWER_METER_NAME + "Unknown units %llu.\n", + resource->caps.units); + res = -EINVAL; + goto end; + } + + /* Grab the string data */ + str = &resource->model_number; + + for (i = 11; i < 14; i++) { + union acpi_object *element = &(pss->package.elements[i]); + + if (element->type != ACPI_TYPE_STRING) { + res = -EINVAL; + goto error; + } + + *str = kzalloc(sizeof(u8) * (element->string.length + 1), + GFP_KERNEL); + if (!*str) { + res = -ENOMEM; + goto error; + } + + strncpy(*str, element->string.pointer, element->string.length); + str++; + } + + dev_info(&resource->acpi_dev->dev, "Found ACPI power meter.\n"); + goto end; +error: + str = &resource->model_number; + for (i = 0; i < 3; i++, str++) + kfree(*str); +end: + kfree(buffer.pointer); + return res; +} + +/* Handle ACPI event notifications */ +static void acpi_power_meter_notify(struct acpi_device *device, u32 event) +{ + struct acpi_power_meter_resource *resource; + int res; + + if (!device || !acpi_driver_data(device)) + return; + + resource = acpi_driver_data(device); + + mutex_lock(&resource->lock); + switch (event) { + case METER_NOTIFY_CONFIG: + free_capabilities(resource); + res = read_capabilities(resource); + if (res) + break; + + remove_attrs(resource); + setup_attrs(resource); + break; + case METER_NOTIFY_TRIP: + sysfs_notify(&device->dev.kobj, NULL, POWER_AVERAGE_NAME); + update_meter(resource); + break; + case METER_NOTIFY_CAP: + sysfs_notify(&device->dev.kobj, NULL, POWER_CAP_NAME); + update_cap(resource); + break; + case METER_NOTIFY_INTERVAL: + sysfs_notify(&device->dev.kobj, NULL, POWER_AVG_INTERVAL_NAME); + update_avg_interval(resource); + break; + case METER_NOTIFY_CAPPING: + sysfs_notify(&device->dev.kobj, NULL, POWER_ALARM_NAME); + dev_info(&device->dev, "Capping in progress.\n"); + break; + default: + BUG(); + } + mutex_unlock(&resource->lock); + + acpi_bus_generate_netlink_event(ACPI_POWER_METER_CLASS, + dev_name(&device->dev), event, 0); +} + +static int acpi_power_meter_add(struct acpi_device *device) +{ + int res; + struct acpi_power_meter_resource *resource; + + if (!device) + return -EINVAL; + + resource = kzalloc(sizeof(struct acpi_power_meter_resource), + GFP_KERNEL); + if (!resource) + return -ENOMEM; + + resource->sensors_valid = 0; + resource->acpi_dev = device; + mutex_init(&resource->lock); + strcpy(acpi_device_name(device), ACPI_POWER_METER_DEVICE_NAME); + strcpy(acpi_device_class(device), ACPI_POWER_METER_CLASS); + device->driver_data = resource; + + free_capabilities(resource); + res = read_capabilities(resource); + if (res) + goto exit_free; + + resource->trip[0] = resource->trip[1] = -1; + + res = setup_attrs(resource); + if (res) + goto exit_free; + + resource->hwmon_dev = hwmon_device_register(&device->dev); + if (IS_ERR(resource->hwmon_dev)) { + res = PTR_ERR(resource->hwmon_dev); + goto exit_remove; + } + + res = 0; + goto exit; + +exit_remove: + remove_attrs(resource); +exit_free: + kfree(resource); +exit: + return res; +} + +static int acpi_power_meter_remove(struct acpi_device *device, int type) +{ + struct acpi_power_meter_resource *resource; + + if (!device || !acpi_driver_data(device)) + return -EINVAL; + + resource = acpi_driver_data(device); + hwmon_device_unregister(resource->hwmon_dev); + + free_capabilities(resource); + remove_attrs(resource); + + kfree(resource); + return 0; +} + +static int acpi_power_meter_resume(struct acpi_device *device) +{ + struct acpi_power_meter_resource *resource; + + if (!device || !acpi_driver_data(device)) + return -EINVAL; + + resource = acpi_driver_data(device); + free_capabilities(resource); + read_capabilities(resource); + + return 0; +} + +static struct acpi_driver acpi_power_meter_driver = { + .name = "power_meter", + .class = ACPI_POWER_METER_CLASS, + .ids = power_meter_ids, + .ops = { + .add = acpi_power_meter_add, + .remove = acpi_power_meter_remove, + .resume = acpi_power_meter_resume, + .notify = acpi_power_meter_notify, + }, +}; + +/* Module init/exit routines */ +static int __init enable_cap_knobs(const struct dmi_system_id *d) +{ + cap_in_hardware = 1; + return 0; +} + +static struct dmi_system_id __initdata pm_dmi_table[] = { + { + enable_cap_knobs, "IBM Active Energy Manager", + { + DMI_MATCH(DMI_SYS_VENDOR, "IBM") + }, + }, + {} +}; + +static int __init acpi_power_meter_init(void) +{ + int result; + + if (acpi_disabled) + return -ENODEV; + + dmi_check_system(pm_dmi_table); + + result = acpi_bus_register_driver(&acpi_power_meter_driver); + if (result < 0) + return -ENODEV; + + return 0; +} + +static void __exit acpi_power_meter_exit(void) +{ + acpi_bus_unregister_driver(&acpi_power_meter_driver); +} + +MODULE_AUTHOR("Darrick J. Wong "); +MODULE_DESCRIPTION("ACPI 4.0 power meter driver"); +MODULE_LICENSE("GPL"); + +module_param(force_cap_on, bool, 0644); +MODULE_PARM_DESC(force_cap_on, "Enable power cap even it is unsafe to do so."); + +module_init(acpi_power_meter_init); +module_exit(acpi_power_meter_exit);