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(struct thermal_zone_device *tz, int *temp)
48{
49 struct max77620_therm_info *mtherm = thermal_zone_device_priv(tzd: tz);
50 unsigned int val;
51 int ret;
52
53 ret = regmap_read(map: mtherm->rmap, MAX77620_REG_STATLBT, val: &val);
54 if (ret < 0)
55 return ret;
56
57 if (val & MAX77620_IRQ_TJALRM2_MASK)
58 *temp = MAX77620_TJALARM2_TEMP;
59 else if (val & MAX77620_IRQ_TJALRM1_MASK)
60 *temp = MAX77620_TJALARM1_TEMP;
61 else
62 *temp = MAX77620_NORMAL_OPERATING_TEMP;
63
64 return 0;
65}
66
67static const struct thermal_zone_device_ops max77620_thermal_ops = {
68 .get_temp = max77620_thermal_read_temp,
69};
70
71static irqreturn_t max77620_thermal_irq(int irq, void *data)
72{
73 struct max77620_therm_info *mtherm = data;
74
75 if (irq == mtherm->irq_tjalarm1)
76 dev_warn(mtherm->dev, "Junction Temp Alarm1(120C) occurred\n");
77 else if (irq == mtherm->irq_tjalarm2)
78 dev_crit(mtherm->dev, "Junction Temp Alarm2(140C) occurred\n");
79
80 thermal_zone_device_update(mtherm->tz_device,
81 THERMAL_EVENT_UNSPECIFIED);
82
83 return IRQ_HANDLED;
84}
85
86static int max77620_thermal_probe(struct platform_device *pdev)
87{
88 struct max77620_therm_info *mtherm;
89 int ret;
90
91 mtherm = devm_kzalloc(dev: &pdev->dev, size: sizeof(*mtherm), GFP_KERNEL);
92 if (!mtherm)
93 return -ENOMEM;
94
95 mtherm->irq_tjalarm1 = platform_get_irq(pdev, 0);
96 mtherm->irq_tjalarm2 = platform_get_irq(pdev, 1);
97 if ((mtherm->irq_tjalarm1 < 0) || (mtherm->irq_tjalarm2 < 0)) {
98 dev_err(&pdev->dev, "Alarm irq number not available\n");
99 return -EINVAL;
100 }
101
102 mtherm->dev = &pdev->dev;
103 mtherm->rmap = dev_get_regmap(dev: pdev->dev.parent, NULL);
104 if (!mtherm->rmap) {
105 dev_err(&pdev->dev, "Failed to get parent regmap\n");
106 return -ENODEV;
107 }
108
109 /*
110 * The reference taken to the parent's node which will be balanced on
111 * reprobe or on platform-device release.
112 */
113 device_set_of_node_from_dev(dev: &pdev->dev, dev2: pdev->dev.parent);
114
115 mtherm->tz_device = devm_thermal_of_zone_register(dev: &pdev->dev, id: 0,
116 data: mtherm, ops: &max77620_thermal_ops);
117 if (IS_ERR(ptr: mtherm->tz_device))
118 return PTR_ERR(ptr: mtherm->tz_device);
119
120 ret = devm_request_threaded_irq(dev: &pdev->dev, irq: mtherm->irq_tjalarm1, NULL,
121 thread_fn: max77620_thermal_irq,
122 IRQF_ONESHOT | IRQF_SHARED,
123 devname: dev_name(dev: &pdev->dev), dev_id: mtherm);
124 if (ret < 0) {
125 dev_err(&pdev->dev, "Failed to request irq1: %d\n", ret);
126 return ret;
127 }
128
129 ret = devm_request_threaded_irq(dev: &pdev->dev, irq: mtherm->irq_tjalarm2, NULL,
130 thread_fn: max77620_thermal_irq,
131 IRQF_ONESHOT | IRQF_SHARED,
132 devname: dev_name(dev: &pdev->dev), dev_id: mtherm);
133 if (ret < 0) {
134 dev_err(&pdev->dev, "Failed to request irq2: %d\n", ret);
135 return ret;
136 }
137
138 return 0;
139}
140
141static struct platform_device_id max77620_thermal_devtype[] = {
142 { .name = "max77620-thermal", },
143 {},
144};
145MODULE_DEVICE_TABLE(platform, max77620_thermal_devtype);
146
147static struct platform_driver max77620_thermal_driver = {
148 .driver = {
149 .name = "max77620-thermal",
150 },
151 .probe = max77620_thermal_probe,
152 .id_table = max77620_thermal_devtype,
153};
154
155module_platform_driver(max77620_thermal_driver);
156
157MODULE_DESCRIPTION("Max77620 Junction temperature Thermal driver");
158MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
159MODULE_AUTHOR("Mallikarjun Kasoju <mkasoju@nvidia.com>");
160MODULE_LICENSE("GPL v2");
161

source code of linux/drivers/thermal/max77620_thermal.c