linux/drivers/thermal/broadcom/ns-thermal.c

107 lines
2.7 KiB
C

/*
* Copyright (C) 2017 Rafał Miłecki <rafal@milecki.pl>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/module.h>
#include <linux/of_address.h>
#include <linux/platform_device.h>
#include <linux/thermal.h>
#define PVTMON_CONTROL0 0x00
#define PVTMON_CONTROL0_SEL_MASK 0x0000000e
#define PVTMON_CONTROL0_SEL_TEMP_MONITOR 0x00000000
#define PVTMON_CONTROL0_SEL_TEST_MODE 0x0000000e
#define PVTMON_STATUS 0x08
struct ns_thermal {
struct thermal_zone_device *tz;
void __iomem *pvtmon;
};
static int ns_thermal_get_temp(void *data, int *temp)
{
struct ns_thermal *ns_thermal = data;
int offset = thermal_zone_get_offset(ns_thermal->tz);
int slope = thermal_zone_get_slope(ns_thermal->tz);
u32 val;
val = readl(ns_thermal->pvtmon + PVTMON_CONTROL0);
if ((val & PVTMON_CONTROL0_SEL_MASK) != PVTMON_CONTROL0_SEL_TEMP_MONITOR) {
/* Clear current mode selection */
val &= ~PVTMON_CONTROL0_SEL_MASK;
/* Set temp monitor mode (it's the default actually) */
val |= PVTMON_CONTROL0_SEL_TEMP_MONITOR;
writel(val, ns_thermal->pvtmon + PVTMON_CONTROL0);
}
val = readl(ns_thermal->pvtmon + PVTMON_STATUS);
*temp = slope * val + offset;
return 0;
}
static const struct thermal_zone_of_device_ops ns_thermal_ops = {
.get_temp = ns_thermal_get_temp,
};
static int ns_thermal_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct ns_thermal *ns_thermal;
ns_thermal = devm_kzalloc(dev, sizeof(*ns_thermal), GFP_KERNEL);
if (!ns_thermal)
return -ENOMEM;
ns_thermal->pvtmon = of_iomap(dev_of_node(dev), 0);
if (WARN_ON(!ns_thermal->pvtmon))
return -ENOENT;
ns_thermal->tz = devm_thermal_zone_of_sensor_register(dev, 0,
ns_thermal,
&ns_thermal_ops);
if (IS_ERR(ns_thermal->tz)) {
iounmap(ns_thermal->pvtmon);
return PTR_ERR(ns_thermal->tz);
}
platform_set_drvdata(pdev, ns_thermal);
return 0;
}
static int ns_thermal_remove(struct platform_device *pdev)
{
struct ns_thermal *ns_thermal = platform_get_drvdata(pdev);
iounmap(ns_thermal->pvtmon);
return 0;
}
static const struct of_device_id ns_thermal_of_match[] = {
{ .compatible = "brcm,ns-thermal", },
{},
};
MODULE_DEVICE_TABLE(of, ns_thermal_of_match);
static struct platform_driver ns_thermal_driver = {
.probe = ns_thermal_probe,
.remove = ns_thermal_remove,
.driver = {
.name = "ns-thermal",
.of_match_table = ns_thermal_of_match,
},
};
module_platform_driver(ns_thermal_driver);
MODULE_AUTHOR("Rafał Miłecki <rafal@milecki.pl>");
MODULE_DESCRIPTION("Northstar thermal driver");
MODULE_LICENSE("GPL v2");