cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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max77620_thermal.c (4669B)


      1// SPDX-License-Identifier: GPL-2.0-only
      2/*
      3 * Junction temperature thermal driver for Maxim Max77620.
      4 *
      5 * Copyright (c) 2016, NVIDIA CORPORATION.  All rights reserved.
      6 *
      7 * Author: Laxman Dewangan <ldewangan@nvidia.com>
      8 *	   Mallikarjun Kasoju <mkasoju@nvidia.com>
      9 */
     10
     11#include <linux/irq.h>
     12#include <linux/interrupt.h>
     13#include <linux/mfd/max77620.h>
     14#include <linux/module.h>
     15#include <linux/of.h>
     16#include <linux/platform_device.h>
     17#include <linux/regmap.h>
     18#include <linux/slab.h>
     19#include <linux/thermal.h>
     20
     21#define MAX77620_NORMAL_OPERATING_TEMP	100000
     22#define MAX77620_TJALARM1_TEMP		120000
     23#define MAX77620_TJALARM2_TEMP		140000
     24
     25struct max77620_therm_info {
     26	struct device			*dev;
     27	struct regmap			*rmap;
     28	struct thermal_zone_device	*tz_device;
     29	int				irq_tjalarm1;
     30	int				irq_tjalarm2;
     31};
     32
     33/**
     34 * max77620_thermal_read_temp: Read PMIC die temperatue.
     35 * @data:	Device specific data.
     36 * @temp:	Temperature in millidegrees Celsius
     37 *
     38 * The actual temperature of PMIC die is not available from PMIC.
     39 * PMIC only tells the status if it has crossed or not the threshold level
     40 * of 120degC or 140degC.
     41 * If threshold has not been crossed then assume die temperature as 100degC
     42 * else 120degC or 140deG based on the PMIC die temp threshold status.
     43 *
     44 * Return 0 on success otherwise error number to show reason of failure.
     45 */
     46
     47static int max77620_thermal_read_temp(void *data, int *temp)
     48{
     49	struct max77620_therm_info *mtherm = data;
     50	unsigned int val;
     51	int ret;
     52
     53	ret = regmap_read(mtherm->rmap, MAX77620_REG_STATLBT, &val);
     54	if (ret < 0) {
     55		dev_err(mtherm->dev, "Failed to read STATLBT: %d\n", ret);
     56		return ret;
     57	}
     58
     59	if (val & MAX77620_IRQ_TJALRM2_MASK)
     60		*temp = MAX77620_TJALARM2_TEMP;
     61	else if (val & MAX77620_IRQ_TJALRM1_MASK)
     62		*temp = MAX77620_TJALARM1_TEMP;
     63	else
     64		*temp = MAX77620_NORMAL_OPERATING_TEMP;
     65
     66	return 0;
     67}
     68
     69static const struct thermal_zone_of_device_ops max77620_thermal_ops = {
     70	.get_temp = max77620_thermal_read_temp,
     71};
     72
     73static irqreturn_t max77620_thermal_irq(int irq, void *data)
     74{
     75	struct max77620_therm_info *mtherm = data;
     76
     77	if (irq == mtherm->irq_tjalarm1)
     78		dev_warn(mtherm->dev, "Junction Temp Alarm1(120C) occurred\n");
     79	else if (irq == mtherm->irq_tjalarm2)
     80		dev_crit(mtherm->dev, "Junction Temp Alarm2(140C) occurred\n");
     81
     82	thermal_zone_device_update(mtherm->tz_device,
     83				   THERMAL_EVENT_UNSPECIFIED);
     84
     85	return IRQ_HANDLED;
     86}
     87
     88static int max77620_thermal_probe(struct platform_device *pdev)
     89{
     90	struct max77620_therm_info *mtherm;
     91	int ret;
     92
     93	mtherm = devm_kzalloc(&pdev->dev, sizeof(*mtherm), GFP_KERNEL);
     94	if (!mtherm)
     95		return -ENOMEM;
     96
     97	mtherm->irq_tjalarm1 = platform_get_irq(pdev, 0);
     98	mtherm->irq_tjalarm2 = platform_get_irq(pdev, 1);
     99	if ((mtherm->irq_tjalarm1 < 0) || (mtherm->irq_tjalarm2 < 0)) {
    100		dev_err(&pdev->dev, "Alarm irq number not available\n");
    101		return -EINVAL;
    102	}
    103
    104	mtherm->dev = &pdev->dev;
    105	mtherm->rmap = dev_get_regmap(pdev->dev.parent, NULL);
    106	if (!mtherm->rmap) {
    107		dev_err(&pdev->dev, "Failed to get parent regmap\n");
    108		return -ENODEV;
    109	}
    110
    111	/*
    112	 * The reference taken to the parent's node which will be balanced on
    113	 * reprobe or on platform-device release.
    114	 */
    115	device_set_of_node_from_dev(&pdev->dev, pdev->dev.parent);
    116
    117	mtherm->tz_device = devm_thermal_zone_of_sensor_register(&pdev->dev, 0,
    118				mtherm, &max77620_thermal_ops);
    119	if (IS_ERR(mtherm->tz_device)) {
    120		ret = PTR_ERR(mtherm->tz_device);
    121		dev_err(&pdev->dev, "Failed to register thermal zone: %d\n",
    122			ret);
    123		return ret;
    124	}
    125
    126	ret = devm_request_threaded_irq(&pdev->dev, mtherm->irq_tjalarm1, NULL,
    127					max77620_thermal_irq,
    128					IRQF_ONESHOT | IRQF_SHARED,
    129					dev_name(&pdev->dev), mtherm);
    130	if (ret < 0) {
    131		dev_err(&pdev->dev, "Failed to request irq1: %d\n", ret);
    132		return ret;
    133	}
    134
    135	ret = devm_request_threaded_irq(&pdev->dev, mtherm->irq_tjalarm2, NULL,
    136					max77620_thermal_irq,
    137					IRQF_ONESHOT | IRQF_SHARED,
    138					dev_name(&pdev->dev), mtherm);
    139	if (ret < 0) {
    140		dev_err(&pdev->dev, "Failed to request irq2: %d\n", ret);
    141		return ret;
    142	}
    143
    144	platform_set_drvdata(pdev, mtherm);
    145
    146	return 0;
    147}
    148
    149static struct platform_device_id max77620_thermal_devtype[] = {
    150	{ .name = "max77620-thermal", },
    151	{},
    152};
    153MODULE_DEVICE_TABLE(platform, max77620_thermal_devtype);
    154
    155static struct platform_driver max77620_thermal_driver = {
    156	.driver = {
    157		.name = "max77620-thermal",
    158	},
    159	.probe = max77620_thermal_probe,
    160	.id_table = max77620_thermal_devtype,
    161};
    162
    163module_platform_driver(max77620_thermal_driver);
    164
    165MODULE_DESCRIPTION("Max77620 Junction temperature Thermal driver");
    166MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
    167MODULE_AUTHOR("Mallikarjun Kasoju <mkasoju@nvidia.com>");
    168MODULE_LICENSE("GPL v2");