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authorArnd Bergmann <arnd@arndb.de>2015-10-14 17:07:32 +0200
committerArnd Bergmann <arnd@arndb.de>2015-10-14 17:07:32 +0200
commitc049adc9fd2937562b4880bdc35b8303ff56d425 (patch)
treef75d32289b1053b3e65cb0e7d330079bee2c9a9b /drivers/hwmon
parent273395f0c2973b96a35772f8aa3b65c25517a45d (diff)
parent68acc77a2d5197141ba376fd8872eccb43bfcd7d (diff)
Merge tag 'arm-scpi-for-v4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux into next/drivers
Merge "ARM System Control and Power Interface(SCPI) support" from Sudeep Holla It adds support for the following features provided by SCP firmware using different subsystems in Linux: 1. SCPI mailbox protocol driver which using mailbox framework 2. Clocks provided by SCP using clock framework 3. CPU DVFS(cpufreq) using existing arm-big-little driver 4. SCPI based sensors including temperature sensors * tag 'arm-scpi-for-v4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux: hwmon: Support thermal zones registration for SCP temperature sensors hwmon: Support sensors exported via ARM SCP interface firmware: arm_scpi: Extend to support sensors Documentation: add DT bindings for ARM SCPI sensors cpufreq: arm_big_little: add SCPI interface driver clk: scpi: add support for cpufreq virtual device clk: add support for clocks provided by SCP(System Control Processor) firmware: add support for ARM System Control and Power Interface(SCPI) protocol Documentation: add DT binding for ARM System Control and Power Interface(SCPI) protocol
Diffstat (limited to 'drivers/hwmon')
-rw-r--r--drivers/hwmon/Kconfig8
-rw-r--r--drivers/hwmon/Makefile1
-rw-r--r--drivers/hwmon/scpi-hwmon.c288
3 files changed, 297 insertions, 0 deletions
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index e13c902e8966..50146bb69833 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..2c1241bbf9af
--- /dev/null
+++ b/drivers/hwmon/scpi-hwmon.c
@@ -0,0 +1,288 @@
+/*
+ * System Control and Power Interface(SCPI) based hwmon sensor driver
+ *
+ * Copyright (C) 2015 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/scpi_protocol.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+#include <linux/thermal.h>
+
+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_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)
+{
+ 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 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;
+ 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;
+
+ platform_set_drvdata(pdev, scpi_sensors);
+
+ hwdev = devm_hwmon_device_register_with_groups(dev,
+ "scpi_sensors", scpi_sensors, scpi_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(&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[] = {
+ {.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,
+ .remove = scpi_hwmon_remove,
+};
+module_platform_driver(scpi_hwmon_platdrv);
+
+MODULE_AUTHOR("Punit Agrawal <punit.agrawal@arm.com>");
+MODULE_DESCRIPTION("ARM SCPI HWMON interface driver");
+MODULE_LICENSE("GPL v2");