--- /dev/null
+/*
+ * ST Thermal Sensor Driver core routines
+ * Author: Ajit Pal Singh <ajitpal.singh@st.com>
+ *
+ * Copyright (C) 2003-2014 STMicroelectronics (R&D) Limited
+ *
+ * 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.
+ *
+ */
+
+#include <linux/clk.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+
+#include "st_thermal.h"
+
+/* The Thermal Framework expects millidegrees */
+#define mcelsius(temp) ((temp) * 1000)
+
+/*
+ * Function to allocate regfields which are common
+ * between syscfg and memory mapped based sensors
+ */
+static int st_thermal_alloc_regfields(struct st_thermal_sensor *sensor)
+{
+ struct device *dev = sensor->dev;
+ struct regmap *regmap = sensor->regmap;
+ const struct reg_field *reg_fields = sensor->cdata->reg_fields;
+
+ sensor->dcorrect = devm_regmap_field_alloc(dev, regmap,
+ reg_fields[DCORRECT]);
+
+ sensor->overflow = devm_regmap_field_alloc(dev, regmap,
+ reg_fields[OVERFLOW]);
+
+ sensor->temp_data = devm_regmap_field_alloc(dev, regmap,
+ reg_fields[DATA]);
+
+ if (IS_ERR(sensor->dcorrect) ||
+ IS_ERR(sensor->overflow) ||
+ IS_ERR(sensor->temp_data)) {
+ dev_err(dev, "failed to allocate common regfields\n");
+ return -EINVAL;
+ }
+
+ return sensor->ops->alloc_regfields(sensor);
+}
+
+static int st_thermal_sensor_on(struct st_thermal_sensor *sensor)
+{
+ int ret;
+ struct device *dev = sensor->dev;
+
+ ret = clk_prepare_enable(sensor->clk);
+ if (ret) {
+ dev_err(dev, "failed to enable clk\n");
+ return ret;
+ }
+
+ ret = sensor->ops->power_ctrl(sensor, POWER_ON);
+ if (ret) {
+ dev_err(dev, "failed to power on sensor\n");
+ clk_disable_unprepare(sensor->clk);
+ }
+
+ return ret;
+}
+
+static int st_thermal_sensor_off(struct st_thermal_sensor *sensor)
+{
+ int ret;
+
+ ret = sensor->ops->power_ctrl(sensor, POWER_OFF);
+ if (ret)
+ return ret;
+
+ clk_disable_unprepare(sensor->clk);
+
+ return 0;
+}
+
+static int st_thermal_calibration(struct st_thermal_sensor *sensor)
+{
+ int ret;
+ unsigned int val;
+ struct device *dev = sensor->dev;
+
+ /* Check if sensor calibration data is already written */
+ ret = regmap_field_read(sensor->dcorrect, &val);
+ if (ret) {
+ dev_err(dev, "failed to read calibration data\n");
+ return ret;
+ }
+
+ if (!val) {
+ /*
+ * Sensor calibration value not set by bootloader,
+ * default calibration data to be used
+ */
+ ret = regmap_field_write(sensor->dcorrect,
+ sensor->cdata->calibration_val);
+ if (ret)
+ dev_err(dev, "failed to set calibration data\n");
+ }
+
+ return ret;
+}
+
+/* Callback to get temperature from HW*/
+static int st_thermal_get_temp(struct thermal_zone_device *th,
+ unsigned long *temperature)
+{
+ struct st_thermal_sensor *sensor = th->devdata;
+ struct device *dev = sensor->dev;
+ unsigned int temp;
+ unsigned int overflow;
+ int ret;
+
+ ret = regmap_field_read(sensor->overflow, &overflow);
+ if (ret)
+ return ret;
+ if (overflow)
+ return -EIO;
+
+ ret = regmap_field_read(sensor->temp_data, &temp);
+ if (ret)
+ return ret;
+
+ temp += sensor->cdata->temp_adjust_val;
+ temp = mcelsius(temp);
+
+ dev_dbg(dev, "temperature: %d\n", temp);
+
+ *temperature = temp;
+
+ return 0;
+}
+
+static int st_thermal_get_trip_type(struct thermal_zone_device *th,
+ int trip, enum thermal_trip_type *type)
+{
+ struct st_thermal_sensor *sensor = th->devdata;
+ struct device *dev = sensor->dev;
+
+ switch (trip) {
+ case 0:
+ *type = THERMAL_TRIP_CRITICAL;
+ break;
+ default:
+ dev_err(dev, "invalid trip point\n");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int st_thermal_get_trip_temp(struct thermal_zone_device *th,
+ int trip, unsigned long *temp)
+{
+ struct st_thermal_sensor *sensor = th->devdata;
+ struct device *dev = sensor->dev;
+
+ switch (trip) {
+ case 0:
+ *temp = mcelsius(sensor->cdata->crit_temp);
+ break;
+ default:
+ dev_err(dev, "Invalid trip point\n");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static struct thermal_zone_device_ops st_tz_ops = {
+ .get_temp = st_thermal_get_temp,
+ .get_trip_type = st_thermal_get_trip_type,
+ .get_trip_temp = st_thermal_get_trip_temp,
+};
+
+int st_thermal_register(struct platform_device *pdev,
+ const struct of_device_id *st_thermal_of_match)
+{
+ struct st_thermal_sensor *sensor;
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ const struct of_device_id *match;
+
+ int polling_delay;
+ int ret;
+
+ if (!np) {
+ dev_err(dev, "device tree node not found\n");
+ return -EINVAL;
+ }
+
+ sensor = devm_kzalloc(dev, sizeof(*sensor), GFP_KERNEL);
+ if (!sensor)
+ return -ENOMEM;
+
+ sensor->dev = dev;
+
+ match = of_match_device(st_thermal_of_match, dev);
+ if (!(match && match->data))
+ return -EINVAL;
+
+ sensor->cdata = match->data;
+ if (!sensor->cdata->ops)
+ return -EINVAL;
+
+ sensor->ops = sensor->cdata->ops;
+
+ ret = sensor->ops->regmap_init(sensor);
+ if (ret)
+ return ret;
+
+ ret = st_thermal_alloc_regfields(sensor);
+ if (ret)
+ return ret;
+
+ sensor->clk = devm_clk_get(dev, "thermal");
+ if (IS_ERR(sensor->clk)) {
+ dev_err(dev, "failed to fetch clock\n");
+ return PTR_ERR(sensor->clk);
+ }
+
+ if (sensor->ops->register_enable_irq) {
+ ret = sensor->ops->register_enable_irq(sensor);
+ if (ret)
+ return ret;
+ }
+
+ ret = st_thermal_sensor_on(sensor);
+ if (ret)
+ return ret;
+
+ ret = st_thermal_calibration(sensor);
+ if (ret)
+ goto sensor_off;
+
+ polling_delay = sensor->ops->register_enable_irq ? 0 : 1000;
+
+ sensor->thermal_dev =
+ thermal_zone_device_register(dev_name(dev), 1, 0, sensor,
+ &st_tz_ops, NULL, 0, polling_delay);
+ if (IS_ERR(sensor->thermal_dev)) {
+ dev_err(dev, "failed to register thermal zone device\n");
+ ret = PTR_ERR(sensor->thermal_dev);
+ goto sensor_off;
+ }
+
+ platform_set_drvdata(pdev, sensor);
+
+ return 0;
+
+sensor_off:
+ st_thermal_sensor_off(sensor);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(st_thermal_register);
+
+int st_thermal_unregister(struct platform_device *pdev)
+{
+ struct st_thermal_sensor *sensor = platform_get_drvdata(pdev);
+
+ st_thermal_sensor_off(sensor);
+ thermal_zone_device_unregister(sensor->thermal_dev);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(st_thermal_unregister);
+
+#ifdef CONFIG_PM_SLEEP
+static int st_thermal_suspend(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct st_thermal_sensor *sensor = platform_get_drvdata(pdev);
+
+ return st_thermal_sensor_off(sensor);
+}
+
+static int st_thermal_resume(struct device *dev)
+{
+ int ret;
+ struct platform_device *pdev = to_platform_device(dev);
+ struct st_thermal_sensor *sensor = platform_get_drvdata(pdev);
+
+ ret = st_thermal_sensor_on(sensor);
+ if (ret)
+ return ret;
+
+ ret = st_thermal_calibration(sensor);
+ if (ret)
+ return ret;
+
+ if (sensor->ops->enable_irq) {
+ ret = sensor->ops->enable_irq(sensor);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+#endif
+
+SIMPLE_DEV_PM_OPS(st_thermal_pm_ops, st_thermal_suspend, st_thermal_resume);
+EXPORT_SYMBOL_GPL(st_thermal_pm_ops);
+
+MODULE_AUTHOR("STMicroelectronics (R&D) Limited <ajitpal.singh@st.com>");
+MODULE_DESCRIPTION("STMicroelectronics STi SoC Thermal Sensor Driver");
+MODULE_LICENSE("GPL v2");
Code Review / kvmfornfv.git / blobdiff