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1/*
2 hwmon.c - part of lm_sensors, Linux kernel modules for hardware monitoring
3
4 This file defines the sysfs class "hwmon", for use by sensors drivers.
5
6 Copyright (C) 2005 Mark M. Hoffman <mhoffman@lightlink.com>
7
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; version 2 of the License.
11*/
12
13#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14
15#include <linux/module.h>
16#include <linux/device.h>
17#include <linux/err.h>
18#include <linux/kdev_t.h>
19#include <linux/idr.h>
20#include <linux/hwmon.h>
21#include <linux/gfp.h>
22#include <linux/spinlock.h>
23#include <linux/pci.h>
24
25#define HWMON_ID_PREFIX "hwmon"
26#define HWMON_ID_FORMAT HWMON_ID_PREFIX "%d"
27
28static struct class *hwmon_class;
29
30static DEFINE_IDR(hwmon_idr);
31static DEFINE_SPINLOCK(idr_lock);
32
33/**
34 * hwmon_device_register - register w/ hwmon
35 * @dev: the device to register
36 *
37 * hwmon_device_unregister() must be called when the device is no
38 * longer needed.
39 *
40 * Returns the pointer to the new device.
41 */
42struct device *hwmon_device_register(struct device *dev)
43{
44 struct device *hwdev;
45 int id, err;
46
47again:
48 if (unlikely(idr_pre_get(&hwmon_idr, GFP_KERNEL) == 0))
49 return ERR_PTR(-ENOMEM);
50
51 spin_lock(&idr_lock);
52 err = idr_get_new(&hwmon_idr, NULL, &id);
53 spin_unlock(&idr_lock);
54
55 if (unlikely(err == -EAGAIN))
56 goto again;
57 else if (unlikely(err))
58 return ERR_PTR(err);
59
60 id = id & MAX_ID_MASK;
61 hwdev = device_create(hwmon_class, dev, MKDEV(0, 0), NULL,
62 HWMON_ID_FORMAT, id);
63
64 if (IS_ERR(hwdev)) {
65 spin_lock(&idr_lock);
66 idr_remove(&hwmon_idr, id);
67 spin_unlock(&idr_lock);
68 }
69
70 return hwdev;
71}
72
73/**
74 * hwmon_device_unregister - removes the previously registered class device
75 *
76 * @dev: the class device to destroy
77 */
78void hwmon_device_unregister(struct device *dev)
79{
80 int id;
81
82 if (likely(sscanf(dev_name(dev), HWMON_ID_FORMAT, &id) == 1)) {
83 device_unregister(dev);
84 spin_lock(&idr_lock);
85 idr_remove(&hwmon_idr, id);
86 spin_unlock(&idr_lock);
87 } else
88 dev_dbg(dev->parent,
89 "hwmon_device_unregister() failed: bad class ID!\n");
90}
91
92static void __init hwmon_pci_quirks(void)
93{
94#if defined CONFIG_X86 && defined CONFIG_PCI
95 struct pci_dev *sb;
96 u16 base;
97 u8 enable;
98
99 /* Open access to 0x295-0x296 on MSI MS-7031 */
100 sb = pci_get_device(PCI_VENDOR_ID_ATI, 0x436c, NULL);
101 if (sb &&
102 (sb->subsystem_vendor == 0x1462 && /* MSI */
103 sb->subsystem_device == 0x0031)) { /* MS-7031 */
104
105 pci_read_config_byte(sb, 0x48, &enable);
106 pci_read_config_word(sb, 0x64, &base);
107
108 if (base == 0 && !(enable & BIT(2))) {
109 dev_info(&sb->dev,
110 "Opening wide generic port at 0x295\n");
111 pci_write_config_word(sb, 0x64, 0x295);
112 pci_write_config_byte(sb, 0x48, enable | BIT(2));
113 }
114 }
115#endif
116}
117
118static int __init hwmon_init(void)
119{
120 hwmon_pci_quirks();
121
122 hwmon_class = class_create(THIS_MODULE, "hwmon");
123 if (IS_ERR(hwmon_class)) {
124 pr_err("couldn't create sysfs class\n");
125 return PTR_ERR(hwmon_class);
126 }
127 return 0;
128}
129
130static void __exit hwmon_exit(void)
131{
132 class_destroy(hwmon_class);
133}
134
135subsys_initcall(hwmon_init);
136module_exit(hwmon_exit);
137
138EXPORT_SYMBOL_GPL(hwmon_device_register);
139EXPORT_SYMBOL_GPL(hwmon_device_unregister);
140
141MODULE_AUTHOR("Mark M. Hoffman <mhoffman@lightlink.com>");
142MODULE_DESCRIPTION("hardware monitoring sysfs/class support");
143MODULE_LICENSE("GPL");
144
1/*
2 * hwmon.c - part of lm_sensors, Linux kernel modules for hardware monitoring
3 *
4 * This file defines the sysfs class "hwmon", for use by sensors drivers.
5 *
6 * Copyright (C) 2005 Mark M. Hoffman <mhoffman@lightlink.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; version 2 of the License.
11 */
12
13#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14
15#include <linux/module.h>
16#include <linux/device.h>
17#include <linux/err.h>
18#include <linux/slab.h>
19#include <linux/kdev_t.h>
20#include <linux/idr.h>
21#include <linux/hwmon.h>
22#include <linux/gfp.h>
23#include <linux/spinlock.h>
24#include <linux/pci.h>
25#include <linux/string.h>
26
27#define HWMON_ID_PREFIX "hwmon"
28#define HWMON_ID_FORMAT HWMON_ID_PREFIX "%d"
29
30struct hwmon_device {
31 const char *name;
32 struct device dev;
33};
34#define to_hwmon_device(d) container_of(d, struct hwmon_device, dev)
35
36static ssize_t
37show_name(struct device *dev, struct device_attribute *attr, char *buf)
38{
39 return sprintf(buf, "%s\n", to_hwmon_device(dev)->name);
40}
41static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
42
43static struct attribute *hwmon_dev_attrs[] = {
44 &dev_attr_name.attr,
45 NULL
46};
47
48static umode_t hwmon_dev_name_is_visible(struct kobject *kobj,
49 struct attribute *attr, int n)
50{
51 struct device *dev = container_of(kobj, struct device, kobj);
52
53 if (to_hwmon_device(dev)->name == NULL)
54 return 0;
55
56 return attr->mode;
57}
58
59static struct attribute_group hwmon_dev_attr_group = {
60 .attrs = hwmon_dev_attrs,
61 .is_visible = hwmon_dev_name_is_visible,
62};
63
64static const struct attribute_group *hwmon_dev_attr_groups[] = {
65 &hwmon_dev_attr_group,
66 NULL
67};
68
69static void hwmon_dev_release(struct device *dev)
70{
71 kfree(to_hwmon_device(dev));
72}
73
74static struct class hwmon_class = {
75 .name = "hwmon",
76 .owner = THIS_MODULE,
77 .dev_groups = hwmon_dev_attr_groups,
78 .dev_release = hwmon_dev_release,
79};
80
81static DEFINE_IDA(hwmon_ida);
82
83/**
84 * hwmon_device_register_with_groups - register w/ hwmon
85 * @dev: the parent device
86 * @name: hwmon name attribute
87 * @drvdata: driver data to attach to created device
88 * @groups: List of attribute groups to create
89 *
90 * hwmon_device_unregister() must be called when the device is no
91 * longer needed.
92 *
93 * Returns the pointer to the new device.
94 */
95struct device *
96hwmon_device_register_with_groups(struct device *dev, const char *name,
97 void *drvdata,
98 const struct attribute_group **groups)
99{
100 struct hwmon_device *hwdev;
101 int err, id;
102
103 /* Do not accept invalid characters in hwmon name attribute */
104 if (name && (!strlen(name) || strpbrk(name, "-* \t\n")))
105 return ERR_PTR(-EINVAL);
106
107 id = ida_simple_get(&hwmon_ida, 0, 0, GFP_KERNEL);
108 if (id < 0)
109 return ERR_PTR(id);
110
111 hwdev = kzalloc(sizeof(*hwdev), GFP_KERNEL);
112 if (hwdev == NULL) {
113 err = -ENOMEM;
114 goto ida_remove;
115 }
116
117 hwdev->name = name;
118 hwdev->dev.class = &hwmon_class;
119 hwdev->dev.parent = dev;
120 hwdev->dev.groups = groups;
121 hwdev->dev.of_node = dev ? dev->of_node : NULL;
122 dev_set_drvdata(&hwdev->dev, drvdata);
123 dev_set_name(&hwdev->dev, HWMON_ID_FORMAT, id);
124 err = device_register(&hwdev->dev);
125 if (err)
126 goto free;
127
128 return &hwdev->dev;
129
130free:
131 kfree(hwdev);
132ida_remove:
133 ida_simple_remove(&hwmon_ida, id);
134 return ERR_PTR(err);
135}
136EXPORT_SYMBOL_GPL(hwmon_device_register_with_groups);
137
138/**
139 * hwmon_device_register - register w/ hwmon
140 * @dev: the device to register
141 *
142 * hwmon_device_unregister() must be called when the device is no
143 * longer needed.
144 *
145 * Returns the pointer to the new device.
146 */
147struct device *hwmon_device_register(struct device *dev)
148{
149 return hwmon_device_register_with_groups(dev, NULL, NULL, NULL);
150}
151EXPORT_SYMBOL_GPL(hwmon_device_register);
152
153/**
154 * hwmon_device_unregister - removes the previously registered class device
155 *
156 * @dev: the class device to destroy
157 */
158void hwmon_device_unregister(struct device *dev)
159{
160 int id;
161
162 if (likely(sscanf(dev_name(dev), HWMON_ID_FORMAT, &id) == 1)) {
163 device_unregister(dev);
164 ida_simple_remove(&hwmon_ida, id);
165 } else
166 dev_dbg(dev->parent,
167 "hwmon_device_unregister() failed: bad class ID!\n");
168}
169EXPORT_SYMBOL_GPL(hwmon_device_unregister);
170
171static void devm_hwmon_release(struct device *dev, void *res)
172{
173 struct device *hwdev = *(struct device **)res;
174
175 hwmon_device_unregister(hwdev);
176}
177
178/**
179 * devm_hwmon_device_register_with_groups - register w/ hwmon
180 * @dev: the parent device
181 * @name: hwmon name attribute
182 * @drvdata: driver data to attach to created device
183 * @groups: List of attribute groups to create
184 *
185 * Returns the pointer to the new device. The new device is automatically
186 * unregistered with the parent device.
187 */
188struct device *
189devm_hwmon_device_register_with_groups(struct device *dev, const char *name,
190 void *drvdata,
191 const struct attribute_group **groups)
192{
193 struct device **ptr, *hwdev;
194
195 if (!dev)
196 return ERR_PTR(-EINVAL);
197
198 ptr = devres_alloc(devm_hwmon_release, sizeof(*ptr), GFP_KERNEL);
199 if (!ptr)
200 return ERR_PTR(-ENOMEM);
201
202 hwdev = hwmon_device_register_with_groups(dev, name, drvdata, groups);
203 if (IS_ERR(hwdev))
204 goto error;
205
206 *ptr = hwdev;
207 devres_add(dev, ptr);
208 return hwdev;
209
210error:
211 devres_free(ptr);
212 return hwdev;
213}
214EXPORT_SYMBOL_GPL(devm_hwmon_device_register_with_groups);
215
216static int devm_hwmon_match(struct device *dev, void *res, void *data)
217{
218 struct device **hwdev = res;
219
220 return *hwdev == data;
221}
222
223/**
224 * devm_hwmon_device_unregister - removes a previously registered hwmon device
225 *
226 * @dev: the parent device of the device to unregister
227 */
228void devm_hwmon_device_unregister(struct device *dev)
229{
230 WARN_ON(devres_release(dev, devm_hwmon_release, devm_hwmon_match, dev));
231}
232EXPORT_SYMBOL_GPL(devm_hwmon_device_unregister);
233
234static void __init hwmon_pci_quirks(void)
235{
236#if defined CONFIG_X86 && defined CONFIG_PCI
237 struct pci_dev *sb;
238 u16 base;
239 u8 enable;
240
241 /* Open access to 0x295-0x296 on MSI MS-7031 */
242 sb = pci_get_device(PCI_VENDOR_ID_ATI, 0x436c, NULL);
243 if (sb) {
244 if (sb->subsystem_vendor == 0x1462 && /* MSI */
245 sb->subsystem_device == 0x0031) { /* MS-7031 */
246 pci_read_config_byte(sb, 0x48, &enable);
247 pci_read_config_word(sb, 0x64, &base);
248
249 if (base == 0 && !(enable & BIT(2))) {
250 dev_info(&sb->dev,
251 "Opening wide generic port at 0x295\n");
252 pci_write_config_word(sb, 0x64, 0x295);
253 pci_write_config_byte(sb, 0x48,
254 enable | BIT(2));
255 }
256 }
257 pci_dev_put(sb);
258 }
259#endif
260}
261
262static int __init hwmon_init(void)
263{
264 int err;
265
266 hwmon_pci_quirks();
267
268 err = class_register(&hwmon_class);
269 if (err) {
270 pr_err("couldn't register hwmon sysfs class\n");
271 return err;
272 }
273 return 0;
274}
275
276static void __exit hwmon_exit(void)
277{
278 class_unregister(&hwmon_class);
279}
280
281subsys_initcall(hwmon_init);
282module_exit(hwmon_exit);
283
284MODULE_AUTHOR("Mark M. Hoffman <mhoffman@lightlink.com>");
285MODULE_DESCRIPTION("hardware monitoring sysfs/class support");
286MODULE_LICENSE("GPL");
287