2 hwmon.c - part of lm_sensors, Linux kernel modules for hardware monitoring
4 This file defines the sysfs class "hwmon", for use by sensors drivers.
6 Copyright (C) 2005 Mark M. Hoffman <mhoffman@lightlink.com>
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.
13 #include <linux/module.h>
14 #include <linux/device.h>
15 #include <linux/err.h>
16 #include <linux/kdev_t.h>
17 #include <linux/idr.h>
18 #include <linux/hwmon.h>
19 #include <linux/gfp.h>
20 #include <linux/spinlock.h>
21 #include <linux/pci.h>
23 #define HWMON_ID_PREFIX "hwmon"
24 #define HWMON_ID_FORMAT HWMON_ID_PREFIX "%d"
26 static struct class *hwmon_class;
28 static DEFINE_IDR(hwmon_idr);
29 static DEFINE_SPINLOCK(idr_lock);
32 * hwmon_device_register - register w/ hwmon
33 * @dev: the device to register
35 * hwmon_device_unregister() must be called when the device is no
38 * Returns the pointer to the new device.
40 struct device *hwmon_device_register(struct device *dev)
46 if (unlikely(idr_pre_get(&hwmon_idr, GFP_KERNEL) == 0))
47 return ERR_PTR(-ENOMEM);
50 err = idr_get_new(&hwmon_idr, NULL, &id);
51 spin_unlock(&idr_lock);
53 if (unlikely(err == -EAGAIN))
55 else if (unlikely(err))
58 id = id & MAX_ID_MASK;
59 hwdev = device_create(hwmon_class, dev, MKDEV(0, 0), NULL,
64 idr_remove(&hwmon_idr, id);
65 spin_unlock(&idr_lock);
72 * hwmon_device_unregister - removes the previously registered class device
74 * @dev: the class device to destroy
76 void hwmon_device_unregister(struct device *dev)
80 if (likely(sscanf(dev_name(dev), HWMON_ID_FORMAT, &id) == 1)) {
81 device_unregister(dev);
83 idr_remove(&hwmon_idr, id);
84 spin_unlock(&idr_lock);
87 "hwmon_device_unregister() failed: bad class ID!\n");
90 static void __init hwmon_pci_quirks(void)
92 #if defined CONFIG_X86 && defined CONFIG_PCI
97 /* Open access to 0x295-0x296 on MSI MS-7031 */
98 sb = pci_get_device(PCI_VENDOR_ID_ATI, 0x436c, NULL);
100 (sb->subsystem_vendor == 0x1462 && /* MSI */
101 sb->subsystem_device == 0x0031)) { /* MS-7031 */
103 pci_read_config_byte(sb, 0x48, &enable);
104 pci_read_config_word(sb, 0x64, &base);
106 if (base == 0 && !(enable & BIT(2))) {
108 "Opening wide generic port at 0x295\n");
109 pci_write_config_word(sb, 0x64, 0x295);
110 pci_write_config_byte(sb, 0x48, enable | BIT(2));
116 static int __init hwmon_init(void)
120 hwmon_class = class_create(THIS_MODULE, "hwmon");
121 if (IS_ERR(hwmon_class)) {
122 printk(KERN_ERR "hwmon.c: couldn't create sysfs class\n");
123 return PTR_ERR(hwmon_class);
128 static void __exit hwmon_exit(void)
130 class_destroy(hwmon_class);
133 subsys_initcall(hwmon_init);
134 module_exit(hwmon_exit);
136 EXPORT_SYMBOL_GPL(hwmon_device_register);
137 EXPORT_SYMBOL_GPL(hwmon_device_unregister);
139 MODULE_AUTHOR("Mark M. Hoffman <mhoffman@lightlink.com>");
140 MODULE_DESCRIPTION("hardware monitoring sysfs/class support");
141 MODULE_LICENSE("GPL");