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/*
* ST Thermal Sensor Driver for memory mapped sensors.
* 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/of.h>
#include <linux/module.h>
#include "st_thermal.h"
#define STIH416_MPE_CONF 0x0
#define STIH416_MPE_STATUS 0x4
#define STIH416_MPE_INT_THRESH 0x8
#define STIH416_MPE_INT_EN 0xC
/* Power control bits for the memory mapped thermal sensor */
#define THERMAL_PDN BIT(4)
#define THERMAL_SRSTN BIT(10)
static const struct reg_field st_mmap_thermal_regfields[MAX_REGFIELDS] = {
/*
* According to the STIH416 MPE temp sensor data sheet -
* the PDN (Power Down Bit) and SRSTN (Soft Reset Bit) need to be
* written simultaneously for powering on and off the temperature
* sensor. regmap_update_bits() will be used to update the register.
*/
[INT_THRESH_HI] = REG_FIELD(STIH416_MPE_INT_THRESH, 0, 7),
[DCORRECT] = REG_FIELD(STIH416_MPE_CONF, 5, 9),
[OVERFLOW] = REG_FIELD(STIH416_MPE_STATUS, 9, 9),
[DATA] = REG_FIELD(STIH416_MPE_STATUS, 11, 18),
[INT_ENABLE] = REG_FIELD(STIH416_MPE_INT_EN, 0, 0),
};
static irqreturn_t st_mmap_thermal_trip_handler(int irq, void *sdata)
{
struct st_thermal_sensor *sensor = sdata;
thermal_zone_device_update(sensor->thermal_dev,
THERMAL_EVENT_UNSPECIFIED);
return IRQ_HANDLED;
}
/* Private ops for the Memory Mapped based thermal sensors */
static int st_mmap_power_ctrl(struct st_thermal_sensor *sensor,
enum st_thermal_power_state power_state)
{
const unsigned int mask = (THERMAL_PDN | THERMAL_SRSTN);
const unsigned int val = power_state ? mask : 0;
return regmap_update_bits(sensor->regmap, STIH416_MPE_CONF, mask, val);
}
static int st_mmap_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->int_thresh_hi = devm_regmap_field_alloc(dev, regmap,
reg_fields[INT_THRESH_HI]);
sensor->int_enable = devm_regmap_field_alloc(dev, regmap,
reg_fields[INT_ENABLE]);
if (IS_ERR(sensor->int_thresh_hi) || IS_ERR(sensor->int_enable)) {
dev_err(dev, "failed to alloc mmap regfields\n");
return -EINVAL;
}
return 0;
}
static int st_mmap_enable_irq(struct st_thermal_sensor *sensor)
{
int ret;
/* Set upper critical threshold */
ret = regmap_field_write(sensor->int_thresh_hi,
sensor->cdata->crit_temp -
sensor->cdata->temp_adjust_val);
if (ret)
return ret;
return regmap_field_write(sensor->int_enable, 1);
}
static int st_mmap_register_enable_irq(struct st_thermal_sensor *sensor)
{
struct device *dev = sensor->dev;
struct platform_device *pdev = to_platform_device(dev);
int ret;
sensor->irq = platform_get_irq(pdev, 0);
if (sensor->irq < 0) {
dev_err(dev, "failed to register IRQ\n");
return sensor->irq;
}
ret = devm_request_threaded_irq(dev, sensor->irq,
NULL, st_mmap_thermal_trip_handler,
IRQF_TRIGGER_RISING | IRQF_ONESHOT,
dev->driver->name, sensor);
if (ret) {
dev_err(dev, "failed to register IRQ %d\n", sensor->irq);
return ret;
}
return st_mmap_enable_irq(sensor);
}
static const struct regmap_config st_416mpe_regmap_config = {
.reg_bits = 32,
.val_bits = 32,
.reg_stride = 4,
};
static int st_mmap_regmap_init(struct st_thermal_sensor *sensor)
{
struct device *dev = sensor->dev;
struct platform_device *pdev = to_platform_device(dev);
struct resource *res;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res) {
dev_err(dev, "no memory resources defined\n");
return -ENODEV;
}
sensor->mmio_base = devm_ioremap_resource(dev, res);
if (IS_ERR(sensor->mmio_base)) {
dev_err(dev, "failed to remap IO\n");
return PTR_ERR(sensor->mmio_base);
}
sensor->regmap = devm_regmap_init_mmio(dev, sensor->mmio_base,
&st_416mpe_regmap_config);
if (IS_ERR(sensor->regmap)) {
dev_err(dev, "failed to initialise regmap\n");
return PTR_ERR(sensor->regmap);
}
return 0;
}
static const struct st_thermal_sensor_ops st_mmap_sensor_ops = {
.power_ctrl = st_mmap_power_ctrl,
.alloc_regfields = st_mmap_alloc_regfields,
.regmap_init = st_mmap_regmap_init,
.register_enable_irq = st_mmap_register_enable_irq,
.enable_irq = st_mmap_enable_irq,
};
/* Compatible device data stih416 mpe thermal sensor */
static const struct st_thermal_compat_data st_416mpe_cdata = {
.reg_fields = st_mmap_thermal_regfields,
.ops = &st_mmap_sensor_ops,
.calibration_val = 14,
.temp_adjust_val = -95,
.crit_temp = 120,
};
/* Compatible device data stih407 thermal sensor */
static const struct st_thermal_compat_data st_407_cdata = {
.reg_fields = st_mmap_thermal_regfields,
.ops = &st_mmap_sensor_ops,
.calibration_val = 16,
.temp_adjust_val = -95,
.crit_temp = 120,
};
static const struct of_device_id st_mmap_thermal_of_match[] = {
{ .compatible = "st,stih416-mpe-thermal", .data = &st_416mpe_cdata },
{ .compatible = "st,stih407-thermal", .data = &st_407_cdata },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, st_mmap_thermal_of_match);
static int st_mmap_probe(struct platform_device *pdev)
{
return st_thermal_register(pdev, st_mmap_thermal_of_match);
}
static int st_mmap_remove(struct platform_device *pdev)
{
return st_thermal_unregister(pdev);
}
static struct platform_driver st_mmap_thermal_driver = {
.driver = {
.name = "st_thermal_mmap",
.pm = &st_thermal_pm_ops,
.of_match_table = st_mmap_thermal_of_match,
},
.probe = st_mmap_probe,
.remove = st_mmap_remove,
};
module_platform_driver(st_mmap_thermal_driver);
MODULE_AUTHOR("STMicroelectronics (R&D) Limited <ajitpal.singh@st.com>");
MODULE_DESCRIPTION("STMicroelectronics STi SoC Thermal Sensor Driver");
MODULE_LICENSE("GPL v2");