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Mark M. Hoffman12364412005-07-15 21:38:08 -04001/*
Guenter Roeck5ed04882012-01-19 11:02:18 -08002 * 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 */
Mark M. Hoffman12364412005-07-15 21:38:08 -040012
Joe Perchesc95df1a2010-10-20 06:51:37 +000013#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14
Mark M. Hoffman12364412005-07-15 21:38:08 -040015#include <linux/module.h>
16#include <linux/device.h>
17#include <linux/err.h>
Guenter Roeckbab22432013-07-06 13:57:23 -070018#include <linux/slab.h>
Mark M. Hoffman12364412005-07-15 21:38:08 -040019#include <linux/kdev_t.h>
20#include <linux/idr.h>
21#include <linux/hwmon.h>
Tim Schmielau8c65b4a2005-11-07 00:59:43 -080022#include <linux/gfp.h>
Mark M. Hoffmanded2b662006-03-05 23:13:47 +010023#include <linux/spinlock.h>
Jean Delvare2958b1e2009-06-15 18:39:50 +020024#include <linux/pci.h>
Mark M. Hoffman12364412005-07-15 21:38:08 -040025
26#define HWMON_ID_PREFIX "hwmon"
27#define HWMON_ID_FORMAT HWMON_ID_PREFIX "%d"
28
Guenter Roeckbab22432013-07-06 13:57:23 -070029struct hwmon_device {
30 const char *name;
31 struct device dev;
32};
33#define to_hwmon_device(d) container_of(d, struct hwmon_device, dev)
34
35static ssize_t
36show_name(struct device *dev, struct device_attribute *attr, char *buf)
37{
38 return sprintf(buf, "%s\n", to_hwmon_device(dev)->name);
39}
40static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
41
42static struct attribute *hwmon_dev_attrs[] = {
43 &dev_attr_name.attr,
44 NULL
45};
46
47static umode_t hwmon_dev_name_is_visible(struct kobject *kobj,
48 struct attribute *attr, int n)
49{
50 struct device *dev = container_of(kobj, struct device, kobj);
51
52 if (to_hwmon_device(dev)->name == NULL)
53 return 0;
54
55 return attr->mode;
56}
57
58static struct attribute_group hwmon_dev_attr_group = {
59 .attrs = hwmon_dev_attrs,
60 .is_visible = hwmon_dev_name_is_visible,
61};
62
63static const struct attribute_group *hwmon_dev_attr_groups[] = {
64 &hwmon_dev_attr_group,
65 NULL
66};
67
68static void hwmon_dev_release(struct device *dev)
69{
70 kfree(to_hwmon_device(dev));
71}
72
73static struct class hwmon_class = {
74 .name = "hwmon",
75 .owner = THIS_MODULE,
76 .dev_groups = hwmon_dev_attr_groups,
77 .dev_release = hwmon_dev_release,
78};
Mark M. Hoffman12364412005-07-15 21:38:08 -040079
Jonathan Cameron4ca5f462011-10-31 17:10:09 -070080static DEFINE_IDA(hwmon_ida);
Mark M. Hoffman12364412005-07-15 21:38:08 -040081
82/**
Guenter Roeckbab22432013-07-06 13:57:23 -070083 * hwmon_device_register_with_groups - register w/ hwmon
84 * @dev: the parent device
85 * @name: hwmon name attribute
86 * @drvdata: driver data to attach to created device
87 * @groups: List of attribute groups to create
88 *
89 * hwmon_device_unregister() must be called when the device is no
90 * longer needed.
91 *
92 * Returns the pointer to the new device.
93 */
94struct device *
95hwmon_device_register_with_groups(struct device *dev, const char *name,
96 void *drvdata,
97 const struct attribute_group **groups)
98{
99 struct hwmon_device *hwdev;
100 int err, id;
101
102 id = ida_simple_get(&hwmon_ida, 0, 0, GFP_KERNEL);
103 if (id < 0)
104 return ERR_PTR(id);
105
106 hwdev = kzalloc(sizeof(*hwdev), GFP_KERNEL);
107 if (hwdev == NULL) {
108 err = -ENOMEM;
109 goto ida_remove;
110 }
111
112 hwdev->name = name;
113 hwdev->dev.class = &hwmon_class;
114 hwdev->dev.parent = dev;
115 hwdev->dev.groups = groups;
116 hwdev->dev.of_node = dev ? dev->of_node : NULL;
117 dev_set_drvdata(&hwdev->dev, drvdata);
118 dev_set_name(&hwdev->dev, HWMON_ID_FORMAT, id);
119 err = device_register(&hwdev->dev);
120 if (err)
121 goto free;
122
123 return &hwdev->dev;
124
125free:
126 kfree(hwdev);
127ida_remove:
128 ida_simple_remove(&hwmon_ida, id);
129 return ERR_PTR(err);
130}
131EXPORT_SYMBOL_GPL(hwmon_device_register_with_groups);
132
133/**
Tony Jones1beeffe2007-08-20 13:46:20 -0700134 * hwmon_device_register - register w/ hwmon
Mark M. Hoffman12364412005-07-15 21:38:08 -0400135 * @dev: the device to register
136 *
Tony Jones1beeffe2007-08-20 13:46:20 -0700137 * hwmon_device_unregister() must be called when the device is no
Mark M. Hoffman12364412005-07-15 21:38:08 -0400138 * longer needed.
139 *
Tony Jones1beeffe2007-08-20 13:46:20 -0700140 * Returns the pointer to the new device.
Mark M. Hoffman12364412005-07-15 21:38:08 -0400141 */
Tony Jones1beeffe2007-08-20 13:46:20 -0700142struct device *hwmon_device_register(struct device *dev)
Mark M. Hoffman12364412005-07-15 21:38:08 -0400143{
Guenter Roeckbab22432013-07-06 13:57:23 -0700144 return hwmon_device_register_with_groups(dev, NULL, NULL, NULL);
Mark M. Hoffman12364412005-07-15 21:38:08 -0400145}
Frans Meulenbroeks839a9ee2012-01-08 19:34:14 +0100146EXPORT_SYMBOL_GPL(hwmon_device_register);
Mark M. Hoffman12364412005-07-15 21:38:08 -0400147
148/**
149 * hwmon_device_unregister - removes the previously registered class device
150 *
Tony Jones1beeffe2007-08-20 13:46:20 -0700151 * @dev: the class device to destroy
Mark M. Hoffman12364412005-07-15 21:38:08 -0400152 */
Tony Jones1beeffe2007-08-20 13:46:20 -0700153void hwmon_device_unregister(struct device *dev)
Mark M. Hoffman12364412005-07-15 21:38:08 -0400154{
155 int id;
156
Kay Sievers739cf3a2009-01-06 10:44:41 -0800157 if (likely(sscanf(dev_name(dev), HWMON_ID_FORMAT, &id) == 1)) {
Tony Jones1beeffe2007-08-20 13:46:20 -0700158 device_unregister(dev);
Jonathan Cameron4ca5f462011-10-31 17:10:09 -0700159 ida_simple_remove(&hwmon_ida, id);
Mark M. Hoffman12364412005-07-15 21:38:08 -0400160 } else
Tony Jones1beeffe2007-08-20 13:46:20 -0700161 dev_dbg(dev->parent,
Mark M. Hoffman12364412005-07-15 21:38:08 -0400162 "hwmon_device_unregister() failed: bad class ID!\n");
163}
Frans Meulenbroeks839a9ee2012-01-08 19:34:14 +0100164EXPORT_SYMBOL_GPL(hwmon_device_unregister);
Mark M. Hoffman12364412005-07-15 21:38:08 -0400165
Guenter Roeck74188cb2013-07-11 20:00:12 -0700166static void devm_hwmon_release(struct device *dev, void *res)
167{
168 struct device *hwdev = *(struct device **)res;
169
170 hwmon_device_unregister(hwdev);
171}
172
173/**
174 * devm_hwmon_device_register_with_groups - register w/ hwmon
175 * @dev: the parent device
176 * @name: hwmon name attribute
177 * @drvdata: driver data to attach to created device
178 * @groups: List of attribute groups to create
179 *
180 * Returns the pointer to the new device. The new device is automatically
181 * unregistered with the parent device.
182 */
183struct device *
184devm_hwmon_device_register_with_groups(struct device *dev, const char *name,
185 void *drvdata,
186 const struct attribute_group **groups)
187{
188 struct device **ptr, *hwdev;
189
190 if (!dev)
191 return ERR_PTR(-EINVAL);
192
193 ptr = devres_alloc(devm_hwmon_release, sizeof(*ptr), GFP_KERNEL);
194 if (!ptr)
195 return ERR_PTR(-ENOMEM);
196
197 hwdev = hwmon_device_register_with_groups(dev, name, drvdata, groups);
198 if (IS_ERR(hwdev))
199 goto error;
200
201 *ptr = hwdev;
202 devres_add(dev, ptr);
203 return hwdev;
204
205error:
206 devres_free(ptr);
207 return hwdev;
208}
209EXPORT_SYMBOL_GPL(devm_hwmon_device_register_with_groups);
210
211static int devm_hwmon_match(struct device *dev, void *res, void *data)
212{
213 struct device **hwdev = res;
214
215 return *hwdev == data;
216}
217
218/**
219 * devm_hwmon_device_unregister - removes a previously registered hwmon device
220 *
221 * @dev: the parent device of the device to unregister
222 */
223void devm_hwmon_device_unregister(struct device *dev)
224{
225 WARN_ON(devres_release(dev, devm_hwmon_release, devm_hwmon_match, dev));
226}
227EXPORT_SYMBOL_GPL(devm_hwmon_device_unregister);
228
Jean Delvare2958b1e2009-06-15 18:39:50 +0200229static void __init hwmon_pci_quirks(void)
230{
231#if defined CONFIG_X86 && defined CONFIG_PCI
232 struct pci_dev *sb;
233 u16 base;
234 u8 enable;
235
236 /* Open access to 0x295-0x296 on MSI MS-7031 */
237 sb = pci_get_device(PCI_VENDOR_ID_ATI, 0x436c, NULL);
Jean Delvared6dab7d2012-12-19 22:16:59 +0100238 if (sb) {
239 if (sb->subsystem_vendor == 0x1462 && /* MSI */
240 sb->subsystem_device == 0x0031) { /* MS-7031 */
241 pci_read_config_byte(sb, 0x48, &enable);
242 pci_read_config_word(sb, 0x64, &base);
Jean Delvare2958b1e2009-06-15 18:39:50 +0200243
Jean Delvared6dab7d2012-12-19 22:16:59 +0100244 if (base == 0 && !(enable & BIT(2))) {
245 dev_info(&sb->dev,
246 "Opening wide generic port at 0x295\n");
247 pci_write_config_word(sb, 0x64, 0x295);
248 pci_write_config_byte(sb, 0x48,
249 enable | BIT(2));
250 }
Jean Delvare2958b1e2009-06-15 18:39:50 +0200251 }
Jean Delvared6dab7d2012-12-19 22:16:59 +0100252 pci_dev_put(sb);
Jean Delvare2958b1e2009-06-15 18:39:50 +0200253 }
254#endif
255}
256
Mark M. Hoffman12364412005-07-15 21:38:08 -0400257static int __init hwmon_init(void)
258{
Guenter Roeckbab22432013-07-06 13:57:23 -0700259 int err;
260
Jean Delvare2958b1e2009-06-15 18:39:50 +0200261 hwmon_pci_quirks();
262
Guenter Roeckbab22432013-07-06 13:57:23 -0700263 err = class_register(&hwmon_class);
264 if (err) {
265 pr_err("couldn't register hwmon sysfs class\n");
266 return err;
Mark M. Hoffman12364412005-07-15 21:38:08 -0400267 }
268 return 0;
269}
270
271static void __exit hwmon_exit(void)
272{
Guenter Roeckbab22432013-07-06 13:57:23 -0700273 class_unregister(&hwmon_class);
Mark M. Hoffman12364412005-07-15 21:38:08 -0400274}
275
David Brownell37f54ee2007-02-14 21:15:04 +0100276subsys_initcall(hwmon_init);
Mark M. Hoffman12364412005-07-15 21:38:08 -0400277module_exit(hwmon_exit);
278
Mark M. Hoffman12364412005-07-15 21:38:08 -0400279MODULE_AUTHOR("Mark M. Hoffman <mhoffman@lightlink.com>");
280MODULE_DESCRIPTION("hardware monitoring sysfs/class support");
281MODULE_LICENSE("GPL");
282