linux/drivers/hwmon/ltq-cputemp.c
Thomas Gleixner 1ccea77e2a treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 13
Based on 2 normalized pattern(s):

  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 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 you
  should have received a copy of the gnu general public license along
  with this program if not see http www gnu org licenses

  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 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 [based]
  [from] [clk] [highbank] [c] you should have received a copy of the
  gnu general public license along with this program if not see http
  www gnu org licenses

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 355 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Jilayne Lovejoy <opensource@jilayne.com>
Reviewed-by: Steve Winslow <swinslow@gmail.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190519154041.837383322@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 11:28:45 +02:00

134 lines
2.8 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/* Lantiq cpu temperature sensor driver
*
* Copyright (C) 2017 Florian Eckert <fe@dev.tdt.de>
*/
#include <linux/bitops.h>
#include <linux/delay.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/of_device.h>
#include <lantiq_soc.h>
/* gphy1 configuration register contains cpu temperature */
#define CGU_GPHY1_CR 0x0040
#define CGU_TEMP_PD BIT(19)
static void ltq_cputemp_enable(void)
{
ltq_cgu_w32(ltq_cgu_r32(CGU_GPHY1_CR) | CGU_TEMP_PD, CGU_GPHY1_CR);
}
static void ltq_cputemp_disable(void *data)
{
ltq_cgu_w32(ltq_cgu_r32(CGU_GPHY1_CR) & ~CGU_TEMP_PD, CGU_GPHY1_CR);
}
static int ltq_read(struct device *dev, enum hwmon_sensor_types type,
u32 attr, int channel, long *temp)
{
int value;
switch (attr) {
case hwmon_temp_input:
/* get the temperature including one decimal place */
value = (ltq_cgu_r32(CGU_GPHY1_CR) >> 9) & 0x01FF;
value = value * 5;
/* range -38 to +154 °C, register value zero is -38.0 °C */
value -= 380;
/* scale temp to millidegree */
value = value * 100;
break;
default:
return -EOPNOTSUPP;
}
*temp = value;
return 0;
}
static umode_t ltq_is_visible(const void *_data, enum hwmon_sensor_types type,
u32 attr, int channel)
{
if (type != hwmon_temp)
return 0;
switch (attr) {
case hwmon_temp_input:
return 0444;
default:
return 0;
}
}
static const struct hwmon_channel_info *ltq_info[] = {
HWMON_CHANNEL_INFO(chip,
HWMON_C_REGISTER_TZ),
HWMON_CHANNEL_INFO(temp,
HWMON_T_INPUT),
NULL
};
static const struct hwmon_ops ltq_hwmon_ops = {
.is_visible = ltq_is_visible,
.read = ltq_read,
};
static const struct hwmon_chip_info ltq_chip_info = {
.ops = &ltq_hwmon_ops,
.info = ltq_info,
};
static int ltq_cputemp_probe(struct platform_device *pdev)
{
struct device *hwmon_dev;
int err = 0;
/* available on vr9 v1.2 SoCs only */
if (ltq_soc_type() != SOC_TYPE_VR9_2)
return -ENODEV;
err = devm_add_action(&pdev->dev, ltq_cputemp_disable, NULL);
if (err)
return err;
ltq_cputemp_enable();
hwmon_dev = devm_hwmon_device_register_with_info(&pdev->dev,
"ltq_cputemp",
NULL,
&ltq_chip_info,
NULL);
if (IS_ERR(hwmon_dev)) {
dev_err(&pdev->dev, "Failed to register as hwmon device");
return PTR_ERR(hwmon_dev);
}
return 0;
}
const struct of_device_id ltq_cputemp_match[] = {
{ .compatible = "lantiq,cputemp" },
{},
};
MODULE_DEVICE_TABLE(of, ltq_cputemp_match);
static struct platform_driver ltq_cputemp_driver = {
.probe = ltq_cputemp_probe,
.driver = {
.name = "ltq-cputemp",
.of_match_table = ltq_cputemp_match,
},
};
module_platform_driver(ltq_cputemp_driver);
MODULE_AUTHOR("Florian Eckert <fe@dev.tdt.de>");
MODULE_DESCRIPTION("Lantiq cpu temperature sensor driver");
MODULE_LICENSE("GPL");