Merge branch 'integrity-check-patch-v2' of git://btrfs.giantdisaster.de/git/btrfs...
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / hwmon / hwmon.c
blob6460487e41b50f8c99b96ea61c09a566cf0aa170
1 /*
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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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>
25 #define HWMON_ID_PREFIX "hwmon"
26 #define HWMON_ID_FORMAT HWMON_ID_PREFIX "%d"
28 static struct class *hwmon_class;
30 static DEFINE_IDA(hwmon_ida);
32 /**
33 * hwmon_device_register - register w/ hwmon
34 * @dev: the device to register
36 * hwmon_device_unregister() must be called when the device is no
37 * longer needed.
39 * Returns the pointer to the new device.
41 struct device *hwmon_device_register(struct device *dev)
43 struct device *hwdev;
44 int id;
46 id = ida_simple_get(&hwmon_ida, 0, 0, GFP_KERNEL);
47 if (id < 0)
48 return ERR_PTR(id);
50 hwdev = device_create(hwmon_class, dev, MKDEV(0, 0), NULL,
51 HWMON_ID_FORMAT, id);
53 if (IS_ERR(hwdev))
54 ida_simple_remove(&hwmon_ida, id);
56 return hwdev;
59 /**
60 * hwmon_device_unregister - removes the previously registered class device
62 * @dev: the class device to destroy
64 void hwmon_device_unregister(struct device *dev)
66 int id;
68 if (likely(sscanf(dev_name(dev), HWMON_ID_FORMAT, &id) == 1)) {
69 device_unregister(dev);
70 ida_simple_remove(&hwmon_ida, id);
71 } else
72 dev_dbg(dev->parent,
73 "hwmon_device_unregister() failed: bad class ID!\n");
76 static void __init hwmon_pci_quirks(void)
78 #if defined CONFIG_X86 && defined CONFIG_PCI
79 struct pci_dev *sb;
80 u16 base;
81 u8 enable;
83 /* Open access to 0x295-0x296 on MSI MS-7031 */
84 sb = pci_get_device(PCI_VENDOR_ID_ATI, 0x436c, NULL);
85 if (sb &&
86 (sb->subsystem_vendor == 0x1462 && /* MSI */
87 sb->subsystem_device == 0x0031)) { /* MS-7031 */
89 pci_read_config_byte(sb, 0x48, &enable);
90 pci_read_config_word(sb, 0x64, &base);
92 if (base == 0 && !(enable & BIT(2))) {
93 dev_info(&sb->dev,
94 "Opening wide generic port at 0x295\n");
95 pci_write_config_word(sb, 0x64, 0x295);
96 pci_write_config_byte(sb, 0x48, enable | BIT(2));
99 #endif
102 static int __init hwmon_init(void)
104 hwmon_pci_quirks();
106 hwmon_class = class_create(THIS_MODULE, "hwmon");
107 if (IS_ERR(hwmon_class)) {
108 pr_err("couldn't create sysfs class\n");
109 return PTR_ERR(hwmon_class);
111 return 0;
114 static void __exit hwmon_exit(void)
116 class_destroy(hwmon_class);
119 subsys_initcall(hwmon_init);
120 module_exit(hwmon_exit);
122 EXPORT_SYMBOL_GPL(hwmon_device_register);
123 EXPORT_SYMBOL_GPL(hwmon_device_unregister);
125 MODULE_AUTHOR("Mark M. Hoffman <mhoffman@lightlink.com>");
126 MODULE_DESCRIPTION("hardware monitoring sysfs/class support");
127 MODULE_LICENSE("GPL");