linux/drivers/thermal/kirkwood_thermal.c
Thomas Gleixner 9c92ab6191 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 282
Based on 1 normalized pattern(s):

  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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 285 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141900.642774971@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05 17:36:37 +02:00

117 lines
2.8 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Kirkwood thermal sensor driver
*
* Copyright (C) 2012 Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
*/
#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/platform_device.h>
#include <linux/thermal.h>
#define KIRKWOOD_THERMAL_VALID_OFFSET 9
#define KIRKWOOD_THERMAL_VALID_MASK 0x1
#define KIRKWOOD_THERMAL_TEMP_OFFSET 10
#define KIRKWOOD_THERMAL_TEMP_MASK 0x1FF
/* Kirkwood Thermal Sensor Dev Structure */
struct kirkwood_thermal_priv {
void __iomem *sensor;
};
static int kirkwood_get_temp(struct thermal_zone_device *thermal,
int *temp)
{
unsigned long reg;
struct kirkwood_thermal_priv *priv = thermal->devdata;
reg = readl_relaxed(priv->sensor);
/* Valid check */
if (!((reg >> KIRKWOOD_THERMAL_VALID_OFFSET) &
KIRKWOOD_THERMAL_VALID_MASK)) {
dev_err(&thermal->device,
"Temperature sensor reading not valid\n");
return -EIO;
}
/*
* Calculate temperature. According to Marvell internal
* documentation the formula for this is:
* Celsius = (322-reg)/1.3625
*/
reg = (reg >> KIRKWOOD_THERMAL_TEMP_OFFSET) &
KIRKWOOD_THERMAL_TEMP_MASK;
*temp = ((3220000000UL - (10000000UL * reg)) / 13625);
return 0;
}
static struct thermal_zone_device_ops ops = {
.get_temp = kirkwood_get_temp,
};
static const struct of_device_id kirkwood_thermal_id_table[] = {
{ .compatible = "marvell,kirkwood-thermal" },
{}
};
static int kirkwood_thermal_probe(struct platform_device *pdev)
{
struct thermal_zone_device *thermal = NULL;
struct kirkwood_thermal_priv *priv;
struct resource *res;
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);
thermal = thermal_zone_device_register("kirkwood_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 kirkwood_thermal_exit(struct platform_device *pdev)
{
struct thermal_zone_device *kirkwood_thermal =
platform_get_drvdata(pdev);
thermal_zone_device_unregister(kirkwood_thermal);
return 0;
}
MODULE_DEVICE_TABLE(of, kirkwood_thermal_id_table);
static struct platform_driver kirkwood_thermal_driver = {
.probe = kirkwood_thermal_probe,
.remove = kirkwood_thermal_exit,
.driver = {
.name = "kirkwood_thermal",
.of_match_table = kirkwood_thermal_id_table,
},
};
module_platform_driver(kirkwood_thermal_driver);
MODULE_AUTHOR("Nobuhiro Iwamatsu <iwamatsu@nigauri.org>");
MODULE_DESCRIPTION("kirkwood thermal driver");
MODULE_LICENSE("GPL");