316 lines
		
	
	
		
			6.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			316 lines
		
	
	
		
			6.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
 | 
						|
 * 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, int *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, int *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");
 |