xref: /openbmc/linux/drivers/hwmon/i5500_temp.c (revision 2cf1c348)
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 
32 static umode_t i5500_is_visible(const void *drvdata, enum hwmon_sensor_types type, u32 attr,
33 				int channel)
34 {
35 	return 0444;
36 }
37 
38 static 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 
86 static const struct hwmon_ops i5500_ops = {
87 	.is_visible = i5500_is_visible,
88 	.read = i5500_read,
89 };
90 
91 static const struct hwmon_channel_info *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 
100 static const struct hwmon_chip_info i5500_chip_info = {
101 	.ops = &i5500_ops,
102 	.info = i5500_info,
103 };
104 
105 static const struct pci_device_id i5500_temp_ids[] = {
106 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x3438) },
107 	{ 0 },
108 };
109 
110 MODULE_DEVICE_TABLE(pci, i5500_temp_ids);
111 
112 static 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 = pci_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 
138 static struct pci_driver i5500_temp_driver = {
139 	.name = "i5500_temp",
140 	.id_table = i5500_temp_ids,
141 	.probe = i5500_temp_probe,
142 };
143 
144 module_pci_driver(i5500_temp_driver);
145 
146 MODULE_AUTHOR("Jean Delvare <jdelvare@suse.de>");
147 MODULE_DESCRIPTION("Intel 5500/5520/X58 chipset thermal sensor driver");
148 MODULE_LICENSE("GPL");
149