1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * i5500_temp - Driver for Intel 5500/5520/X58 chipset thermal sensor
4 *
5 * Copyright (C) 2012, 2014 Jean Delvare <jdelvare@suse.de>
6 */
7
8#include <linux/bitops.h>
9#include <linux/module.h>
10#include <linux/init.h>
11#include <linux/slab.h>
12#include <linux/jiffies.h>
13#include <linux/device.h>
14#include <linux/pci.h>
15#include <linux/hwmon.h>
16#include <linux/err.h>
17#include <linux/mutex.h>
18
19/* Register definitions from datasheet */
20#define REG_TSTHRCATA	0xE2
21#define REG_TSCTRL	0xE8
22#define REG_TSTHRRPEX	0xEB
23#define REG_TSTHRLO	0xEC
24#define REG_TSTHRHI	0xEE
25#define REG_CTHINT	0xF0
26#define REG_TSFSC	0xF3
27#define REG_CTSTS	0xF4
28#define REG_TSTHRRQPI	0xF5
29#define REG_CTCTRL	0xF7
30#define REG_TSTIMER	0xF8
31
32static umode_t i5500_is_visible(const void *drvdata, enum hwmon_sensor_types type, u32 attr,
33				int channel)
34{
35	return 0444;
36}
37
38static int i5500_read(struct device *dev, enum hwmon_sensor_types type, u32 attr, int channel,
39		      long *val)
40{
41	struct pci_dev *pdev = to_pci_dev(dev->parent);
42	u16 tsthr;
43	s8 tsfsc;
44	u8 ctsts;
45
46	switch (type) {
47	case hwmon_temp:
48		switch (attr) {
49		/* Sensor resolution : 0.5 degree C */
50		case hwmon_temp_input:
51			pci_read_config_word(pdev, REG_TSTHRHI, &tsthr);
52			pci_read_config_byte(pdev, REG_TSFSC, &tsfsc);
53			*val = (tsthr - tsfsc) * 500;
54			return 0;
55		case hwmon_temp_max:
56			pci_read_config_word(pdev, REG_TSTHRHI, &tsthr);
57			*val = tsthr * 500;
58			return 0;
59		case hwmon_temp_max_hyst:
60			pci_read_config_word(pdev, REG_TSTHRLO, &tsthr);
61			*val = tsthr * 500;
62			return 0;
63		case hwmon_temp_crit:
64			pci_read_config_word(pdev, REG_TSTHRCATA, &tsthr);
65			*val = tsthr * 500;
66			return 0;
67		case hwmon_temp_max_alarm:
68			pci_read_config_byte(pdev, REG_CTSTS, &ctsts);
69			*val = !!(ctsts & BIT(1));
70			return 0;
71		case hwmon_temp_crit_alarm:
72			pci_read_config_byte(pdev, REG_CTSTS, &ctsts);
73			*val = !!(ctsts & BIT(0));
74			return 0;
75		default:
76			break;
77		}
78		break;
79	default:
80		break;
81	}
82
83	return -EOPNOTSUPP;
84}
85
86static const struct hwmon_ops i5500_ops = {
87	.is_visible = i5500_is_visible,
88	.read = i5500_read,
89};
90
91static const struct hwmon_channel_info * const i5500_info[] = {
92	HWMON_CHANNEL_INFO(chip, HWMON_C_REGISTER_TZ),
93	HWMON_CHANNEL_INFO(temp,
94			   HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MAX_HYST | HWMON_T_CRIT |
95			   HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM
96			   ),
97	NULL
98};
99
100static const struct hwmon_chip_info i5500_chip_info = {
101	.ops = &i5500_ops,
102	.info = i5500_info,
103};
104
105static const struct pci_device_id i5500_temp_ids[] = {
106	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x3438) },
107	{ 0 },
108};
109
110MODULE_DEVICE_TABLE(pci, i5500_temp_ids);
111
112static int i5500_temp_probe(struct pci_dev *pdev,
113			    const struct pci_device_id *id)
114{
115	int err;
116	struct device *hwmon_dev;
117	u32 tstimer;
118	s8 tsfsc;
119
120	err = pcim_enable_device(pdev);
121	if (err) {
122		dev_err(&pdev->dev, "Failed to enable device\n");
123		return err;
124	}
125
126	pci_read_config_byte(pdev, REG_TSFSC, &tsfsc);
127	pci_read_config_dword(pdev, REG_TSTIMER, &tstimer);
128	if (tsfsc == 0x7F && tstimer == 0x07D30D40) {
129		dev_notice(&pdev->dev, "Sensor seems to be disabled\n");
130		return -ENODEV;
131	}
132
133	hwmon_dev = devm_hwmon_device_register_with_info(&pdev->dev, "intel5500", NULL,
134							 &i5500_chip_info, NULL);
135	return PTR_ERR_OR_ZERO(hwmon_dev);
136}
137
138static struct pci_driver i5500_temp_driver = {
139	.name = "i5500_temp",
140	.id_table = i5500_temp_ids,
141	.probe = i5500_temp_probe,
142};
143
144module_pci_driver(i5500_temp_driver);
145
146MODULE_AUTHOR("Jean Delvare <jdelvare@suse.de>");
147MODULE_DESCRIPTION("Intel 5500/5520/X58 chipset thermal sensor driver");
148MODULE_LICENSE("GPL");
149