From b23688aefb8b2c5dd024c172f3143e8a99d2cf17 Mon Sep 17 00:00:00 2001 From: Sudeep Holla Date: Thu, 15 Jun 2017 10:53:17 +0100 Subject: hwmon: add support for sensors exported via ARM SCMI Create a driver to add support for SoC sensors exported by the System Control Processor (SCP) via the System Control and Management Interface (SCMI). 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. Cc: linux-hwmon@vger.kernel.org Acked-by: Guenter Roeck Signed-off-by: Sudeep Holla --- drivers/hwmon/Kconfig | 12 +++ drivers/hwmon/Makefile | 1 + drivers/hwmon/scmi-hwmon.c | 225 +++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 238 insertions(+) create mode 100644 drivers/hwmon/scmi-hwmon.c (limited to 'drivers/hwmon') diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig index ef23553ff5cb..033e57366d56 100644 --- a/drivers/hwmon/Kconfig +++ b/drivers/hwmon/Kconfig @@ -317,6 +317,18 @@ config SENSORS_APPLESMC Say Y here if you have an applicable laptop and want to experience the awesome power of applesmc. +config SENSORS_ARM_SCMI + tristate "ARM SCMI Sensors" + depends on ARM_SCMI_PROTOCOL + depends on THERMAL || !THERMAL_OF + help + This driver provides support for temperature, voltage, current + and power sensors available on SCMI based platforms. The actual + number and type of sensors exported depend on the platform. + + This driver can also be built as a module. If so, the module + will be called scmi-hwmon. + config SENSORS_ARM_SCPI tristate "ARM SCPI Sensors" depends on ARM_SCPI_PROTOCOL diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile index f814b4ace138..e7d52a36e6c4 100644 --- a/drivers/hwmon/Makefile +++ b/drivers/hwmon/Makefile @@ -46,6 +46,7 @@ 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-$(CONFIG_SENSORS_ARM_SCMI) += scmi-hwmon.o obj-$(CONFIG_SENSORS_ARM_SCPI) += scpi-hwmon.o obj-$(CONFIG_SENSORS_ASC7621) += asc7621.o obj-$(CONFIG_SENSORS_ASPEED) += aspeed-pwm-tacho.o diff --git a/drivers/hwmon/scmi-hwmon.c b/drivers/hwmon/scmi-hwmon.c new file mode 100644 index 000000000000..32e750373ced --- /dev/null +++ b/drivers/hwmon/scmi-hwmon.c @@ -0,0 +1,225 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * System Control and Management Interface(SCMI) based hwmon sensor driver + * + * Copyright (C) 2018 ARM Ltd. + * Sudeep Holla + */ + +#include +#include +#include +#include +#include +#include + +struct scmi_sensors { + const struct scmi_handle *handle; + const struct scmi_sensor_info **info[hwmon_max]; +}; + +static int scmi_hwmon_read(struct device *dev, enum hwmon_sensor_types type, + u32 attr, int channel, long *val) +{ + int ret; + u64 value; + const struct scmi_sensor_info *sensor; + struct scmi_sensors *scmi_sensors = dev_get_drvdata(dev); + const struct scmi_handle *h = scmi_sensors->handle; + + sensor = *(scmi_sensors->info[type] + channel); + ret = h->sensor_ops->reading_get(h, sensor->id, false, &value); + if (!ret) + *val = value; + + return ret; +} + +static int +scmi_hwmon_read_string(struct device *dev, enum hwmon_sensor_types type, + u32 attr, int channel, const char **str) +{ + const struct scmi_sensor_info *sensor; + struct scmi_sensors *scmi_sensors = dev_get_drvdata(dev); + + sensor = *(scmi_sensors->info[type] + channel); + *str = sensor->name; + + return 0; +} + +static umode_t +scmi_hwmon_is_visible(const void *drvdata, enum hwmon_sensor_types type, + u32 attr, int channel) +{ + const struct scmi_sensor_info *sensor; + const struct scmi_sensors *scmi_sensors = drvdata; + + sensor = *(scmi_sensors->info[type] + channel); + if (sensor && sensor->name) + return S_IRUGO; + + return 0; +} + +static const struct hwmon_ops scmi_hwmon_ops = { + .is_visible = scmi_hwmon_is_visible, + .read = scmi_hwmon_read, + .read_string = scmi_hwmon_read_string, +}; + +static struct hwmon_chip_info scmi_chip_info = { + .ops = &scmi_hwmon_ops, + .info = NULL, +}; + +static int scmi_hwmon_add_chan_info(struct hwmon_channel_info *scmi_hwmon_chan, + struct device *dev, int num, + enum hwmon_sensor_types type, u32 config) +{ + int i; + u32 *cfg = devm_kcalloc(dev, num + 1, sizeof(*cfg), GFP_KERNEL); + + if (!cfg) + return -ENOMEM; + + scmi_hwmon_chan->type = type; + scmi_hwmon_chan->config = cfg; + for (i = 0; i < num; i++, cfg++) + *cfg = config; + + return 0; +} + +static enum hwmon_sensor_types scmi_types[] = { + [TEMPERATURE_C] = hwmon_temp, + [VOLTAGE] = hwmon_in, + [CURRENT] = hwmon_curr, + [POWER] = hwmon_power, + [ENERGY] = hwmon_energy, +}; + +static u32 hwmon_attributes[] = { + [hwmon_chip] = HWMON_C_REGISTER_TZ, + [hwmon_temp] = HWMON_T_INPUT | HWMON_T_LABEL, + [hwmon_in] = HWMON_I_INPUT | HWMON_I_LABEL, + [hwmon_curr] = HWMON_C_INPUT | HWMON_C_LABEL, + [hwmon_power] = HWMON_P_INPUT | HWMON_P_LABEL, + [hwmon_energy] = HWMON_E_INPUT | HWMON_E_LABEL, +}; + +static int scmi_hwmon_probe(struct scmi_device *sdev) +{ + int i, idx; + u16 nr_sensors; + enum hwmon_sensor_types type; + struct scmi_sensors *scmi_sensors; + const struct scmi_sensor_info *sensor; + int nr_count[hwmon_max] = {0}, nr_types = 0; + const struct hwmon_chip_info *chip_info; + struct device *hwdev, *dev = &sdev->dev; + struct hwmon_channel_info *scmi_hwmon_chan; + const struct hwmon_channel_info **ptr_scmi_ci; + const struct scmi_handle *handle = sdev->handle; + + if (!handle || !handle->sensor_ops) + return -ENODEV; + + nr_sensors = handle->sensor_ops->count_get(handle); + if (!nr_sensors) + return -EIO; + + scmi_sensors = devm_kzalloc(dev, sizeof(*scmi_sensors), GFP_KERNEL); + if (!scmi_sensors) + return -ENOMEM; + + scmi_sensors->handle = handle; + + for (i = 0; i < nr_sensors; i++) { + sensor = handle->sensor_ops->info_get(handle, i); + if (!sensor) + return PTR_ERR(sensor); + + switch (sensor->type) { + case TEMPERATURE_C: + case VOLTAGE: + case CURRENT: + case POWER: + case ENERGY: + type = scmi_types[sensor->type]; + if (!nr_count[type]) + nr_types++; + nr_count[type]++; + break; + } + } + + if (nr_count[hwmon_temp]) + nr_count[hwmon_chip]++, nr_types++; + + scmi_hwmon_chan = devm_kcalloc(dev, nr_types, sizeof(*scmi_hwmon_chan), + GFP_KERNEL); + if (!scmi_hwmon_chan) + return -ENOMEM; + + ptr_scmi_ci = devm_kcalloc(dev, nr_types + 1, sizeof(*ptr_scmi_ci), + GFP_KERNEL); + if (!ptr_scmi_ci) + return -ENOMEM; + + scmi_chip_info.info = ptr_scmi_ci; + chip_info = &scmi_chip_info; + + for (type = 0; type < hwmon_max && nr_count[type]; type++) { + scmi_hwmon_add_chan_info(scmi_hwmon_chan, dev, nr_count[type], + type, hwmon_attributes[type]); + *ptr_scmi_ci++ = scmi_hwmon_chan++; + + scmi_sensors->info[type] = + devm_kcalloc(dev, nr_count[type], + sizeof(*scmi_sensors->info), GFP_KERNEL); + if (!scmi_sensors->info[type]) + return -ENOMEM; + } + + for (i = nr_sensors - 1; i >= 0 ; i--) { + sensor = handle->sensor_ops->info_get(handle, i); + if (!sensor) + continue; + + switch (sensor->type) { + case TEMPERATURE_C: + case VOLTAGE: + case CURRENT: + case POWER: + case ENERGY: + type = scmi_types[sensor->type]; + idx = --nr_count[type]; + *(scmi_sensors->info[type] + idx) = sensor; + break; + } + } + + hwdev = devm_hwmon_device_register_with_info(dev, "scmi_sensors", + scmi_sensors, chip_info, + NULL); + + return PTR_ERR_OR_ZERO(hwdev); +} + +static const struct scmi_device_id scmi_id_table[] = { + { SCMI_PROTOCOL_SENSOR }, + { }, +}; +MODULE_DEVICE_TABLE(scmi, scmi_id_table); + +static struct scmi_driver scmi_hwmon_drv = { + .name = "scmi-hwmon", + .probe = scmi_hwmon_probe, + .id_table = scmi_id_table, +}; +module_scmi_driver(scmi_hwmon_drv); + +MODULE_AUTHOR("Sudeep Holla "); +MODULE_DESCRIPTION("ARM SCMI HWMON interface driver"); +MODULE_LICENSE("GPL v2"); -- cgit v1.2.3