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-rw-r--r--drivers/hwmon/Kconfig13
-rw-r--r--drivers/hwmon/Makefile1
-rw-r--r--drivers/hwmon/scmi-hwmon.c259
3 files changed, 273 insertions, 0 deletions
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 80a73bfc1a65..6f50a6380789 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -321,6 +321,19 @@ 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 12a32398fdcc..1c873b80a4da 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-$(CONFIG_SENSORS_ARM_SCMI) += scmi-hwmon.o
obj-$(CONFIG_SENSORS_ARM_SCPI) += scpi-hwmon.o
obj-$(CONFIG_SENSORS_ASC7621) += asc7621.o
obj-$(CONFIG_SENSORS_ATXP1) += atxp1.o
diff --git a/drivers/hwmon/scmi-hwmon.c b/drivers/hwmon/scmi-hwmon.c
new file mode 100644
index 000000000000..1e7250fdd940
--- /dev/null
+++ b/drivers/hwmon/scmi-hwmon.c
@@ -0,0 +1,259 @@
+/*
+ * System Control and Management Interface(SCMI) based hwmon sensor driver
+ *
+ * Copyright (C) 2017 ARM Ltd.
+ * Punit Agrawal <punit.agrawal@arm.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 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 <linux/hwmon.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/scmi_protocol.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+#include <linux/thermal.h>
+
+struct sensor_data {
+ const struct scmi_sensor_info *info;
+ struct device_attribute dev_attr_input;
+ struct device_attribute dev_attr_label;
+ char input[20];
+ char label[20];
+};
+
+struct scmi_thermal_zone {
+ int sensor_id;
+ struct scmi_sensors *scmi_sensors;
+};
+
+struct scmi_sensors {
+ const struct scmi_handle *handle;
+ struct sensor_data *data;
+ struct list_head thermal_zones;
+ struct attribute **attrs;
+ struct attribute_group group;
+ const struct attribute_group *groups[2];
+};
+
+static int scmi_read_temp(void *dev, int *temp)
+{
+ struct scmi_thermal_zone *zone = dev;
+ struct scmi_sensors *scmi_sensors = zone->scmi_sensors;
+ const struct scmi_handle *handle = scmi_sensors->handle;
+ struct sensor_data *sensor = &scmi_sensors->data[zone->sensor_id];
+ u64 value;
+ int ret;
+
+ ret = handle->sensor_ops->reading_get(handle, sensor->info->id,
+ false, &value);
+ if (ret)
+ return ret;
+
+ *temp = value;
+ return 0;
+}
+
+/* hwmon callback functions */
+static ssize_t
+scmi_show_sensor(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct scmi_sensors *scmi_sensors = dev_get_drvdata(dev);
+ const struct scmi_handle *handle = scmi_sensors->handle;
+ struct sensor_data *sensor;
+ u64 value;
+ int ret;
+
+ sensor = container_of(attr, struct sensor_data, dev_attr_input);
+
+ ret = handle->sensor_ops->reading_get(handle, sensor->info->id,
+ false, &value);
+ if (ret)
+ return ret;
+
+ return sprintf(buf, "%llu\n", value);
+}
+
+static ssize_t
+scmi_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 struct thermal_zone_of_device_ops scmi_sensor_ops = {
+ .get_temp = scmi_read_temp,
+};
+
+static int scmi_hwmon_probe(struct platform_device *pdev)
+{
+ int idx;
+ u16 nr_sensors, i;
+ int num_temp = 0, num_volt = 0, num_current = 0, num_power = 0;
+ int num_energy = 0;
+ struct device *hwdev, *dev = &pdev->dev;
+ struct scmi_sensors *scmi_sensors;
+ const struct scmi_handle *handle = devm_scmi_handle_get(dev);
+
+ if (IS_ERR_OR_NULL(handle) || !handle->sensor_ops)
+ return -EPROBE_DEFER;
+
+ 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->data = devm_kcalloc(dev, nr_sensors,
+ sizeof(*scmi_sensors->data), GFP_KERNEL);
+ if (!scmi_sensors->data)
+ return -ENOMEM;
+
+ scmi_sensors->attrs = devm_kcalloc(dev, (nr_sensors * 2) + 1,
+ sizeof(*scmi_sensors->attrs), GFP_KERNEL);
+ if (!scmi_sensors->attrs)
+ return -ENOMEM;
+
+ scmi_sensors->handle = handle;
+
+ for (i = 0, idx = 0; i < nr_sensors; i++) {
+ struct sensor_data *sensor = &scmi_sensors->data[idx];
+
+ sensor->info = handle->sensor_ops->info_get(handle, i);
+ if (!sensor->info)
+ return PTR_ERR(sensor->info);
+
+ switch (sensor->info->type) {
+ case TEMPERATURE_C:
+ 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;
+ case ENERGY:
+ snprintf(sensor->input, sizeof(sensor->input),
+ "energy%d_input", num_energy + 1);
+ snprintf(sensor->label, sizeof(sensor->input),
+ "energy%d_label", num_energy + 1);
+ num_energy++;
+ break;
+ default:
+ continue;
+ }
+
+ sensor->dev_attr_input.attr.mode = S_IRUGO;
+ sensor->dev_attr_input.show = scmi_show_sensor;
+ sensor->dev_attr_input.attr.name = sensor->input;
+
+ sensor->dev_attr_label.attr.mode = S_IRUGO;
+ sensor->dev_attr_label.show = scmi_show_label;
+ sensor->dev_attr_label.attr.name = sensor->label;
+
+ scmi_sensors->attrs[idx << 1] = &sensor->dev_attr_input.attr;
+ scmi_sensors->attrs[(idx << 1) + 1] =
+ &sensor->dev_attr_label.attr;
+
+ sysfs_attr_init(scmi_sensors->attrs[idx << 1]);
+ sysfs_attr_init(scmi_sensors->attrs[(idx << 1) + 1]);
+ idx++;
+ }
+
+ scmi_sensors->group.attrs = scmi_sensors->attrs;
+ scmi_sensors->groups[0] = &scmi_sensors->group;
+
+ platform_set_drvdata(pdev, scmi_sensors);
+
+ hwdev = devm_hwmon_device_register_with_groups(dev, "scmi_sensors",
+ scmi_sensors,
+ scmi_sensors->groups);
+
+ 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(&scmi_sensors->thermal_zones);
+ for (i = 0; i < nr_sensors; i++) {
+ struct sensor_data *sensor = &scmi_sensors->data[i];
+ const struct scmi_sensor_info *info = sensor->info;
+ struct thermal_zone_device *z;
+ struct scmi_thermal_zone *zone;
+
+ if (info->type != TEMPERATURE_C)
+ continue;
+
+ zone = devm_kzalloc(dev, sizeof(*zone), GFP_KERNEL);
+ if (!zone)
+ return -ENOMEM;
+
+ zone->sensor_id = i;
+ zone->scmi_sensors = scmi_sensors;
+ z = devm_thermal_zone_of_sensor_register(dev, info->id, zone,
+ &scmi_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(z)) {
+ devm_kfree(dev, zone);
+ continue;
+ }
+ }
+
+ return 0;
+}
+
+static struct platform_driver scmi_hwmon_platdrv = {
+ .driver = {
+ .name = "scmi-hwmon",
+ },
+ .probe = scmi_hwmon_probe,
+};
+module_platform_driver(scmi_hwmon_platdrv);
+
+MODULE_AUTHOR("Punit Agrawal <punit.agrawal@arm.com>");
+MODULE_DESCRIPTION("ARM SCMI HWMON interface driver");
+MODULE_LICENSE("GPL v2");