From ea98b29a05e9c70dbe159cbc6254d111059a2bb9 Mon Sep 17 00:00:00 2001 From: Punit Agrawal Date: Thu, 21 May 2015 15:08:45 +0100 Subject: hwmon: Support sensors exported via ARM SCP interface Create a driver to add support for SoC sensors exported by the System Control Processor (SCP) via the System Control and Power Interface (SCPI). The supported sensor types is one of voltage, temperature, current, and power. The sensor labels and values provided by the SCP are exported via the hwmon sysfs interface. Signed-off-by: Punit Agrawal Acked-by: Guenter Roeck Cc: Sudeep Holla --- drivers/hwmon/Kconfig | 8 ++ drivers/hwmon/Makefile | 1 + drivers/hwmon/scpi-hwmon.c | 186 +++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 195 insertions(+) create mode 100644 drivers/hwmon/scpi-hwmon.c (limited to 'drivers/hwmon') diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig index 500b262b89bb..4663693b58f6 100644 --- a/drivers/hwmon/Kconfig +++ b/drivers/hwmon/Kconfig @@ -321,6 +321,14 @@ config SENSORS_APPLESMC Say Y here if you have an applicable laptop and want to experience the awesome power of applesmc. +config SENSORS_ARM_SCPI + tristate "ARM SCPI Sensors" + depends on ARM_SCPI_PROTOCOL + help + This driver provides support for temperature, voltage, current + and power sensors available on ARM Ltd's SCP based platforms. The + actual number and type of sensors exported depend on the platform. + config SENSORS_ASB100 tristate "Asus ASB100 Bach" depends on X86 && I2C diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile index 9e0f3dd2841d..66e7a4715da7 100644 --- a/drivers/hwmon/Makefile +++ b/drivers/hwmon/Makefile @@ -44,6 +44,7 @@ obj-$(CONFIG_SENSORS_ADT7462) += adt7462.o obj-$(CONFIG_SENSORS_ADT7470) += adt7470.o obj-$(CONFIG_SENSORS_ADT7475) += adt7475.o obj-$(CONFIG_SENSORS_APPLESMC) += applesmc.o +obj-$(CONFIG_SENSORS_ARM_SCPI) += scpi-hwmon.o obj-$(CONFIG_SENSORS_ASC7621) += asc7621.o obj-$(CONFIG_SENSORS_ATXP1) += atxp1.o obj-$(CONFIG_SENSORS_CORETEMP) += coretemp.o diff --git a/drivers/hwmon/scpi-hwmon.c b/drivers/hwmon/scpi-hwmon.c new file mode 100644 index 000000000000..c7d1d1423427 --- /dev/null +++ b/drivers/hwmon/scpi-hwmon.c @@ -0,0 +1,186 @@ +/* + * System Control and Power Interface(SCPI) based hwmon sensor driver + * + * Copyright (C) 2015 ARM Ltd. + * Punit Agrawal + * + * 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 program is distributed "as is" WITHOUT ANY WARRANTY of any + * kind, whether express or implied; without even the implied warranty + * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include +#include +#include +#include +#include +#include + +struct sensor_data { + struct scpi_sensor_info info; + struct device_attribute dev_attr_input; + struct device_attribute dev_attr_label; + char input[20]; + char label[20]; +}; + +struct scpi_sensors { + struct scpi_ops *scpi_ops; + struct sensor_data *data; + struct attribute **attrs; + struct attribute_group group; + const struct attribute_group *groups[2]; +}; + +/* hwmon callback functions */ +static ssize_t +scpi_show_sensor(struct device *dev, struct device_attribute *attr, char *buf) +{ + struct scpi_sensors *scpi_sensors = dev_get_drvdata(dev); + struct scpi_ops *scpi_ops = scpi_sensors->scpi_ops; + struct sensor_data *sensor; + u32 value; + int ret; + + sensor = container_of(attr, struct sensor_data, dev_attr_input); + + ret = scpi_ops->sensor_get_value(sensor->info.sensor_id, &value); + if (ret) + return ret; + + return sprintf(buf, "%u\n", value); +} + +static ssize_t +scpi_show_label(struct device *dev, struct device_attribute *attr, char *buf) +{ + struct sensor_data *sensor; + + sensor = container_of(attr, struct sensor_data, dev_attr_label); + + return sprintf(buf, "%s\n", sensor->info.name); +} + +static int scpi_hwmon_probe(struct platform_device *pdev) +{ + u16 nr_sensors, i; + int num_temp = 0, num_volt = 0, num_current = 0, num_power = 0; + struct scpi_ops *scpi_ops; + struct device *hwdev, *dev = &pdev->dev; + struct scpi_sensors *scpi_sensors; + int ret; + + scpi_ops = get_scpi_ops(); + if (!scpi_ops) + return -EPROBE_DEFER; + + ret = scpi_ops->sensor_get_capability(&nr_sensors); + if (ret) + return ret; + + if (!nr_sensors) + return -ENODEV; + + scpi_sensors = devm_kzalloc(dev, sizeof(*scpi_sensors), GFP_KERNEL); + if (!scpi_sensors) + return -ENOMEM; + + scpi_sensors->data = devm_kcalloc(dev, nr_sensors, + sizeof(*scpi_sensors->data), GFP_KERNEL); + if (!scpi_sensors->data) + return -ENOMEM; + + scpi_sensors->attrs = devm_kcalloc(dev, (nr_sensors * 2) + 1, + sizeof(*scpi_sensors->attrs), GFP_KERNEL); + if (!scpi_sensors->attrs) + return -ENOMEM; + + scpi_sensors->scpi_ops = scpi_ops; + + for (i = 0; i < nr_sensors; i++) { + struct sensor_data *sensor = &scpi_sensors->data[i]; + + ret = scpi_ops->sensor_get_info(i, &sensor->info); + if (ret) + return ret; + + switch (sensor->info.class) { + case TEMPERATURE: + snprintf(sensor->input, sizeof(sensor->input), + "temp%d_input", num_temp + 1); + snprintf(sensor->label, sizeof(sensor->input), + "temp%d_label", num_temp + 1); + num_temp++; + break; + case VOLTAGE: + snprintf(sensor->input, sizeof(sensor->input), + "in%d_input", num_volt); + snprintf(sensor->label, sizeof(sensor->input), + "in%d_label", num_volt); + num_volt++; + break; + case CURRENT: + snprintf(sensor->input, sizeof(sensor->input), + "curr%d_input", num_current + 1); + snprintf(sensor->label, sizeof(sensor->input), + "curr%d_label", num_current + 1); + num_current++; + break; + case POWER: + snprintf(sensor->input, sizeof(sensor->input), + "power%d_input", num_power + 1); + snprintf(sensor->label, sizeof(sensor->input), + "power%d_label", num_power + 1); + num_power++; + break; + default: + break; + } + + sensor->dev_attr_input.attr.mode = S_IRUGO; + sensor->dev_attr_input.show = scpi_show_sensor; + sensor->dev_attr_input.attr.name = sensor->input; + + sensor->dev_attr_label.attr.mode = S_IRUGO; + sensor->dev_attr_label.show = scpi_show_label; + sensor->dev_attr_label.attr.name = sensor->label; + + scpi_sensors->attrs[i << 1] = &sensor->dev_attr_input.attr; + scpi_sensors->attrs[(i << 1) + 1] = &sensor->dev_attr_label.attr; + + sysfs_attr_init(scpi_sensors->attrs[i << 1]); + sysfs_attr_init(scpi_sensors->attrs[(i << 1) + 1]); + } + + scpi_sensors->group.attrs = scpi_sensors->attrs; + scpi_sensors->groups[0] = &scpi_sensors->group; + + hwdev = devm_hwmon_device_register_with_groups(dev, + "scpi_sensors", scpi_sensors, scpi_sensors->groups); + + return PTR_ERR_OR_ZERO(hwdev); +} + +static const struct of_device_id scpi_of_match[] = { + {.compatible = "arm,scpi-sensors"}, + {}, +}; + +static struct platform_driver scpi_hwmon_platdrv = { + .driver = { + .name = "scpi-hwmon", + .owner = THIS_MODULE, + .of_match_table = scpi_of_match, + }, + .probe = scpi_hwmon_probe, +}; +module_platform_driver(scpi_hwmon_platdrv); + +MODULE_AUTHOR("Punit Agrawal "); +MODULE_DESCRIPTION("ARM SCPI HWMON interface driver"); +MODULE_LICENSE("GPL v2"); -- cgit v1.2.1 From 68acc77a2d5197141ba376fd8872eccb43bfcd7d Mon Sep 17 00:00:00 2001 From: Punit Agrawal Date: Wed, 24 Jun 2015 19:03:16 +0100 Subject: hwmon: Support thermal zones registration for SCP temperature sensors Add support to create thermal zones based on the temperature sensors provided by the SCP. The thermal zones can be defined using the thermal DT bindings and should refer to the SCP sensor id to select the sensor. Signed-off-by: Punit Agrawal Acked-by: Guenter Roeck Cc: Eduardo Valentin --- drivers/hwmon/scpi-hwmon.c | 104 ++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 103 insertions(+), 1 deletion(-) (limited to 'drivers/hwmon') diff --git a/drivers/hwmon/scpi-hwmon.c b/drivers/hwmon/scpi-hwmon.c index c7d1d1423427..2c1241bbf9af 100644 --- a/drivers/hwmon/scpi-hwmon.c +++ b/drivers/hwmon/scpi-hwmon.c @@ -20,6 +20,7 @@ #include #include #include +#include struct sensor_data { struct scpi_sensor_info info; @@ -29,14 +30,39 @@ struct sensor_data { char label[20]; }; +struct scpi_thermal_zone { + struct list_head list; + int sensor_id; + struct scpi_sensors *scpi_sensors; + struct thermal_zone_device *tzd; +}; + struct scpi_sensors { struct scpi_ops *scpi_ops; struct sensor_data *data; + struct list_head thermal_zones; struct attribute **attrs; struct attribute_group group; const struct attribute_group *groups[2]; }; +static int scpi_read_temp(void *dev, int *temp) +{ + struct scpi_thermal_zone *zone = dev; + struct scpi_sensors *scpi_sensors = zone->scpi_sensors; + struct scpi_ops *scpi_ops = scpi_sensors->scpi_ops; + struct sensor_data *sensor = &scpi_sensors->data[zone->sensor_id]; + u32 value; + int ret; + + ret = scpi_ops->sensor_get_value(sensor->info.sensor_id, &value); + if (ret) + return ret; + + *temp = value; + return 0; +} + /* hwmon callback functions */ static ssize_t scpi_show_sensor(struct device *dev, struct device_attribute *attr, char *buf) @@ -66,6 +92,24 @@ scpi_show_label(struct device *dev, struct device_attribute *attr, char *buf) return sprintf(buf, "%s\n", sensor->info.name); } +static void +unregister_thermal_zones(struct platform_device *pdev, + struct scpi_sensors *scpi_sensors) +{ + struct list_head *pos; + + list_for_each(pos, &scpi_sensors->thermal_zones) { + struct scpi_thermal_zone *zone; + + zone = list_entry(pos, struct scpi_thermal_zone, list); + thermal_zone_of_sensor_unregister(&pdev->dev, zone->tzd); + } +} + +static struct thermal_zone_of_device_ops scpi_sensor_ops = { + .get_temp = scpi_read_temp, +}; + static int scpi_hwmon_probe(struct platform_device *pdev) { u16 nr_sensors, i; @@ -160,10 +204,67 @@ static int scpi_hwmon_probe(struct platform_device *pdev) scpi_sensors->group.attrs = scpi_sensors->attrs; scpi_sensors->groups[0] = &scpi_sensors->group; + platform_set_drvdata(pdev, scpi_sensors); + hwdev = devm_hwmon_device_register_with_groups(dev, "scpi_sensors", scpi_sensors, scpi_sensors->groups); - return PTR_ERR_OR_ZERO(hwdev); + if (IS_ERR(hwdev)) + return PTR_ERR(hwdev); + + /* + * Register the temperature sensors with the thermal framework + * to allow their usage in setting up the thermal zones from + * device tree. + * + * NOTE: Not all temperature sensors maybe used for thermal + * control + */ + INIT_LIST_HEAD(&scpi_sensors->thermal_zones); + for (i = 0; i < nr_sensors; i++) { + struct sensor_data *sensor = &scpi_sensors->data[i]; + struct scpi_thermal_zone *zone; + + if (sensor->info.class != TEMPERATURE) + continue; + + zone = devm_kzalloc(dev, sizeof(*zone), GFP_KERNEL); + if (!zone) { + ret = -ENOMEM; + goto unregister_tzd; + } + + zone->sensor_id = i; + zone->scpi_sensors = scpi_sensors; + zone->tzd = thermal_zone_of_sensor_register(dev, i, zone, + &scpi_sensor_ops); + /* + * The call to thermal_zone_of_sensor_register returns + * an error for sensors that are not associated with + * any thermal zones or if the thermal subsystem is + * not configured. + */ + if (IS_ERR(zone->tzd)) { + devm_kfree(dev, zone); + continue; + } + list_add(&zone->list, &scpi_sensors->thermal_zones); + } + + return 0; + +unregister_tzd: + unregister_thermal_zones(pdev, scpi_sensors); + return ret; +} + +static int scpi_hwmon_remove(struct platform_device *pdev) +{ + struct scpi_sensors *scpi_sensors = platform_get_drvdata(pdev); + + unregister_thermal_zones(pdev, scpi_sensors); + + return 0; } static const struct of_device_id scpi_of_match[] = { @@ -178,6 +279,7 @@ static struct platform_driver scpi_hwmon_platdrv = { .of_match_table = scpi_of_match, }, .probe = scpi_hwmon_probe, + .remove = scpi_hwmon_remove, }; module_platform_driver(scpi_hwmon_platdrv); -- cgit v1.2.1