/*
* Marvell Armada 370/XP thermal sensor driver
*
* Copyright (C) 2013 Marvell
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
*/
#include <linux/device.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/of.h>
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/of_device.h>
#include <linux/thermal.h>
#define THERMAL_VALID_OFFSET 9
#define THERMAL_VALID_MASK 0x1
#define THERMAL_TEMP_OFFSET 10
#define THERMAL_TEMP_MASK 0x1ff
/* Thermal Manager Control and Status Register */
#define PMU_TDC0_SW_RST_MASK (0x1 << 1)
#define PMU_TM_DISABLE_OFFS 0
#define PMU_TM_DISABLE_MASK (0x1 << PMU_TM_DISABLE_OFFS)
#define PMU_TDC0_REF_CAL_CNT_OFFS 11
#define PMU_TDC0_REF_CAL_CNT_MASK (0x1ff << PMU_TDC0_REF_CAL_CNT_OFFS)
#define PMU_TDC0_OTF_CAL_MASK (0x1 << 30)
#define PMU_TDC0_START_CAL_MASK (0x1 << 25)
struct armada_thermal_ops;
/* Marvell EBU Thermal Sensor Dev Structure */
struct armada_thermal_priv {
void __iomem *sensor;
void __iomem *control;
struct armada_thermal_ops *ops;
};
struct armada_thermal_ops {
/* Initialize the sensor */
void (*init_sensor)(struct armada_thermal_priv *);
/* Test for a valid sensor value (optional) */
bool (*is_valid)(struct armada_thermal_priv *);
};
static void armadaxp_init_sensor(struct armada_thermal_priv *priv)
{
unsigned long reg;
reg = readl_relaxed(priv->control);
reg |= PMU_TDC0_OTF_CAL_MASK;
writel(reg, priv->control);
/* Reference calibration value */
reg &= ~PMU_TDC0_REF_CAL_CNT_MASK;
reg |= (0xf1 << PMU_TDC0_REF_CAL_CNT_OFFS);
writel(reg, priv->control);
/* Reset the sensor */
reg = readl_relaxed(priv->control);
writel((reg | PMU_TDC0_SW_RST_MASK), priv->control);
writel(reg, priv->control);
/* Enable the sensor */
reg = readl_relaxed(priv->sensor);
reg &= ~PMU_TM_DISABLE_MASK;
writel(reg, priv->sensor);
}
static void armada370_init_sensor(struct armada_thermal_priv *priv)
{
unsigned long reg;
reg = readl_relaxed(priv->control);
reg |= PMU_TDC0_OTF_CAL_MASK;
writel(reg, priv->control);
/* Reference calibration value */
reg &= ~PMU_TDC0_REF_CAL_CNT_MASK;
reg |= (0xf1 << PMU_TDC0_REF_CAL_CNT_OFFS);
writel(reg, priv->control);
reg &= ~PMU_TDC0_START_CAL_MASK;
writel(reg, priv->control);
mdelay(10);
}
static bool armada_is_valid(struct armada_thermal_priv *priv)
{
unsigned long reg = readl_relaxed(priv->sensor);
return (reg >> THERMAL_VALID_OFFSET) & THERMAL_VALID_MASK;
}
static int armada_get_temp(struct thermal_zone_device *thermal,
unsigned long *temp)
{
struct armada_thermal_priv *priv = thermal->devdata;
unsigned long reg;
/* Valid check */
if (priv->ops->is_valid && !priv->ops->is_valid(priv)) {
dev_err(&thermal->device,
"Temperature sensor reading not valid\n");
return -EIO;
}
reg = readl_relaxed(priv->sensor);
reg = (reg >> THERMAL_TEMP_OFFSET) & THERMAL_TEMP_MASK;
*temp = (3153000000UL - (10000000UL*reg)) / 13825;
return 0;
}
static struct thermal_zone_device_ops ops = {
.get_temp = armada_get_temp,
};
static const struct armada_thermal_ops armadaxp_ops = {
.init_sensor = armadaxp_init_sensor,
};
static const struct armada_thermal_ops armada370_ops = {
.is_valid = armada_is_valid,
.init_sensor = armada370_init_sensor,
};
static const struct of_device_id armada_thermal_id_table[] = {
{
.compatible = "marvell,armadaxp-thermal",
.data = &armadaxp_ops,
},
{
.compatible = "marvell,armada370-thermal",
.data = &armada370_ops,
},
{
/* sentinel */
},
};
MODULE_DEVICE_TABLE(of, armada_thermal_id_table);
static int armada_thermal_probe(struct platform_device *pdev)
{
struct thermal_zone_device *thermal;
const struct of_device_id *match;
struct armada_thermal_priv *priv;
struct resource *res;
match = of_match_device(armada_thermal_id_table, &pdev->dev);
if (!match)
return -ENODEV;
priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
priv->sensor = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(priv->sensor))
return PTR_ERR(priv->sensor);
res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
priv->control = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(priv->control))
return PTR_ERR(priv->control);
priv->ops = (struct armada_thermal_ops *)match->data;
priv->ops->init_sensor(priv);
thermal = thermal_zone_device_register("armada_thermal", 0, 0,
priv, &ops, NULL, 0, 0);
if (IS_ERR(thermal)) {
dev_err(&pdev->dev,
"Failed to register thermal zone device\n");
return PTR_ERR(thermal);
}
platform_set_drvdata(pdev, thermal);
return 0;
}
static int armada_thermal_exit(struct platform_device *pdev)
{
struct thermal_zone_device *armada_thermal =
platform_get_drvdata(pdev);
thermal_zone_device_unregister(armada_thermal);
return 0;
}
static struct platform_driver armada_thermal_driver = {
.probe = armada_thermal_probe,
.remove = armada_thermal_exit,
.driver = {
.name = "armada_thermal",
.owner = THIS_MODULE,
.of_match_table = armada_thermal_id_table,
},
};
module_platform_driver(armada_thermal_driver);
MODULE_AUTHOR("Ezequiel Garcia <ezequiel.garcia@free-electrons.com>");
MODULE_DESCRIPTION("Armada 370/XP thermal driver");
MODULE_LICENSE("GPL v2");
