thermal: sti: Add support for ST's Memory Mapped based Thermal controller

config ST_THERMAL_SYSCFG

	select ST_THERMAL

	tristate "STi series syscfg register access based thermal sensors"

config ST_THERMAL_MEMMAP

	select ST_THERMAL

	tristate "STi series memory mapped access based thermal sensors"

obj-$(CONFIG_ST_THERMAL)		:= st_thermal.o

obj-$(CONFIG_ST_THERMAL_SYSCFG)		+= st_thermal_syscfg.o

obj-$(CONFIG_ST_THERMAL_MEMMAP)		+= st_thermal_memmap.o

/*

 * 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);

	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 */

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 */

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 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);

int st_mmap_probe(struct platform_device *pdev)

{

	return st_thermal_register(pdev,  st_mmap_thermal_of_match);

}

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",

		.owner  = THIS_MODULE,

		.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");