xref: /openbmc/linux/drivers/hwmon/i5500_temp.c (revision 2c684d89)
1 /*
2  * i5500_temp - Driver for Intel 5500/5520/X58 chipset thermal sensor
3  *
4  * Copyright (C) 2012, 2014 Jean Delvare <jdelvare@suse.de>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  */
16 
17 #include <linux/module.h>
18 #include <linux/init.h>
19 #include <linux/slab.h>
20 #include <linux/jiffies.h>
21 #include <linux/device.h>
22 #include <linux/pci.h>
23 #include <linux/hwmon.h>
24 #include <linux/hwmon-sysfs.h>
25 #include <linux/err.h>
26 #include <linux/mutex.h>
27 
28 /* Register definitions from datasheet */
29 #define REG_TSTHRCATA	0xE2
30 #define REG_TSCTRL	0xE8
31 #define REG_TSTHRRPEX	0xEB
32 #define REG_TSTHRLO	0xEC
33 #define REG_TSTHRHI	0xEE
34 #define REG_CTHINT	0xF0
35 #define REG_TSFSC	0xF3
36 #define REG_CTSTS	0xF4
37 #define REG_TSTHRRQPI	0xF5
38 #define REG_CTCTRL	0xF7
39 #define REG_TSTIMER	0xF8
40 
41 /*
42  * Sysfs stuff
43  */
44 
45 /* Sensor resolution : 0.5 degree C */
46 static ssize_t show_temp(struct device *dev,
47 			 struct device_attribute *devattr, char *buf)
48 {
49 	struct pci_dev *pdev = to_pci_dev(dev->parent);
50 	long temp;
51 	u16 tsthrhi;
52 	s8 tsfsc;
53 
54 	pci_read_config_word(pdev, REG_TSTHRHI, &tsthrhi);
55 	pci_read_config_byte(pdev, REG_TSFSC, &tsfsc);
56 	temp = ((long)tsthrhi - tsfsc) * 500;
57 
58 	return sprintf(buf, "%ld\n", temp);
59 }
60 
61 static ssize_t show_thresh(struct device *dev,
62 			   struct device_attribute *devattr, char *buf)
63 {
64 	struct pci_dev *pdev = to_pci_dev(dev->parent);
65 	int reg = to_sensor_dev_attr(devattr)->index;
66 	long temp;
67 	u16 tsthr;
68 
69 	pci_read_config_word(pdev, reg, &tsthr);
70 	temp = tsthr * 500;
71 
72 	return sprintf(buf, "%ld\n", temp);
73 }
74 
75 static ssize_t show_alarm(struct device *dev,
76 			  struct device_attribute *devattr, char *buf)
77 {
78 	struct pci_dev *pdev = to_pci_dev(dev->parent);
79 	int nr = to_sensor_dev_attr(devattr)->index;
80 	u8 ctsts;
81 
82 	pci_read_config_byte(pdev, REG_CTSTS, &ctsts);
83 	return sprintf(buf, "%u\n", (unsigned int)ctsts & (1 << nr));
84 }
85 
86 static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL);
87 static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO, show_thresh, NULL, 0xE2);
88 static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IRUGO, show_thresh, NULL, 0xEC);
89 static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO, show_thresh, NULL, 0xEE);
90 static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL, 0);
91 static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, 1);
92 
93 static struct attribute *i5500_temp_attrs[] = {
94 	&dev_attr_temp1_input.attr,
95 	&sensor_dev_attr_temp1_crit.dev_attr.attr,
96 	&sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
97 	&sensor_dev_attr_temp1_max.dev_attr.attr,
98 	&sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
99 	&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
100 	NULL
101 };
102 
103 ATTRIBUTE_GROUPS(i5500_temp);
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_groups(&pdev->dev,
134 							   "intel5500", NULL,
135 							   i5500_temp_groups);
136 	return PTR_ERR_OR_ZERO(hwmon_dev);
137 }
138 
139 static struct pci_driver i5500_temp_driver = {
140 	.name = "i5500_temp",
141 	.id_table = i5500_temp_ids,
142 	.probe = i5500_temp_probe,
143 };
144 
145 module_pci_driver(i5500_temp_driver);
146 
147 MODULE_AUTHOR("Jean Delvare <jdelvare@suse.de>");
148 MODULE_DESCRIPTION("Intel 5500/5520/X58 chipset thermal sensor driver");
149 MODULE_LICENSE("GPL");
150