2 * via-cputemp.c - Driver for VIA CPU core temperature monitoring
3 * Copyright (C) 2009 VIA Technologies, Inc.
5 * based on existing coretemp.c, which is
7 * Copyright (C) 2007 Rudolf Marek <r.marek@assembler.cz>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; version 2 of the License.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
24 #include <linux/module.h>
25 #include <linux/init.h>
26 #include <linux/slab.h>
27 #include <linux/hwmon.h>
28 #include <linux/sysfs.h>
29 #include <linux/hwmon-sysfs.h>
30 #include <linux/err.h>
31 #include <linux/mutex.h>
32 #include <linux/list.h>
33 #include <linux/platform_device.h>
34 #include <linux/cpu.h>
36 #include <asm/processor.h>
38 #define DRVNAME "via_cputemp"
40 enum { SHOW_TEMP, SHOW_LABEL, SHOW_NAME };
43 * Functions declaration
46 struct via_cputemp_data {
47 struct device *hwmon_dev;
57 static ssize_t show_name(struct device *dev, struct device_attribute
61 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
62 struct via_cputemp_data *data = dev_get_drvdata(dev);
64 if (attr->index == SHOW_NAME)
65 ret = sprintf(buf, "%s\n", data->name);
67 ret = sprintf(buf, "Core %d\n", data->id);
71 static ssize_t show_temp(struct device *dev,
72 struct device_attribute *devattr, char *buf)
74 struct via_cputemp_data *data = dev_get_drvdata(dev);
78 err = rdmsr_safe_on_cpu(data->id, data->msr, &eax, &edx);
82 return sprintf(buf, "%lu\n", ((unsigned long)eax & 0xffffff) * 1000);
85 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL,
87 static SENSOR_DEVICE_ATTR(temp1_label, S_IRUGO, show_name, NULL, SHOW_LABEL);
88 static SENSOR_DEVICE_ATTR(name, S_IRUGO, show_name, NULL, SHOW_NAME);
90 static struct attribute *via_cputemp_attributes[] = {
91 &sensor_dev_attr_name.dev_attr.attr,
92 &sensor_dev_attr_temp1_label.dev_attr.attr,
93 &sensor_dev_attr_temp1_input.dev_attr.attr,
97 static const struct attribute_group via_cputemp_group = {
98 .attrs = via_cputemp_attributes,
101 static int __devinit via_cputemp_probe(struct platform_device *pdev)
103 struct via_cputemp_data *data;
104 struct cpuinfo_x86 *c = &cpu_data(pdev->id);
108 data = kzalloc(sizeof(struct via_cputemp_data), GFP_KERNEL);
111 dev_err(&pdev->dev, "Out of memory\n");
116 data->name = "via_cputemp";
118 switch (c->x86_model) {
134 /* test if we can access the TEMPERATURE MSR */
135 err = rdmsr_safe_on_cpu(data->id, data->msr, &eax, &edx);
138 "Unable to access TEMPERATURE MSR, giving up\n");
142 platform_set_drvdata(pdev, data);
144 err = sysfs_create_group(&pdev->dev.kobj, &via_cputemp_group);
148 data->hwmon_dev = hwmon_device_register(&pdev->dev);
149 if (IS_ERR(data->hwmon_dev)) {
150 err = PTR_ERR(data->hwmon_dev);
151 dev_err(&pdev->dev, "Class registration failed (%d)\n",
159 sysfs_remove_group(&pdev->dev.kobj, &via_cputemp_group);
161 platform_set_drvdata(pdev, NULL);
167 static int __devexit via_cputemp_remove(struct platform_device *pdev)
169 struct via_cputemp_data *data = platform_get_drvdata(pdev);
171 hwmon_device_unregister(data->hwmon_dev);
172 sysfs_remove_group(&pdev->dev.kobj, &via_cputemp_group);
173 platform_set_drvdata(pdev, NULL);
178 static struct platform_driver via_cputemp_driver = {
180 .owner = THIS_MODULE,
183 .probe = via_cputemp_probe,
184 .remove = __devexit_p(via_cputemp_remove),
188 struct list_head list;
189 struct platform_device *pdev;
193 static LIST_HEAD(pdev_list);
194 static DEFINE_MUTEX(pdev_list_mutex);
196 static int __cpuinit via_cputemp_device_add(unsigned int cpu)
199 struct platform_device *pdev;
200 struct pdev_entry *pdev_entry;
202 pdev = platform_device_alloc(DRVNAME, cpu);
205 printk(KERN_ERR DRVNAME ": Device allocation failed\n");
209 pdev_entry = kzalloc(sizeof(struct pdev_entry), GFP_KERNEL);
212 goto exit_device_put;
215 err = platform_device_add(pdev);
217 printk(KERN_ERR DRVNAME ": Device addition failed (%d)\n",
219 goto exit_device_free;
222 pdev_entry->pdev = pdev;
223 pdev_entry->cpu = cpu;
224 mutex_lock(&pdev_list_mutex);
225 list_add_tail(&pdev_entry->list, &pdev_list);
226 mutex_unlock(&pdev_list_mutex);
233 platform_device_put(pdev);
238 static void __cpuinit via_cputemp_device_remove(unsigned int cpu)
240 struct pdev_entry *p, *n;
241 mutex_lock(&pdev_list_mutex);
242 list_for_each_entry_safe(p, n, &pdev_list, list) {
244 platform_device_unregister(p->pdev);
249 mutex_unlock(&pdev_list_mutex);
252 static int __cpuinit via_cputemp_cpu_callback(struct notifier_block *nfb,
253 unsigned long action, void *hcpu)
255 unsigned int cpu = (unsigned long) hcpu;
259 case CPU_DOWN_FAILED:
260 via_cputemp_device_add(cpu);
262 case CPU_DOWN_PREPARE:
263 via_cputemp_device_remove(cpu);
269 static struct notifier_block via_cputemp_cpu_notifier __refdata = {
270 .notifier_call = via_cputemp_cpu_callback,
273 static int __init via_cputemp_init(void)
276 struct pdev_entry *p, *n;
278 if (cpu_data(0).x86_vendor != X86_VENDOR_CENTAUR) {
279 printk(KERN_DEBUG DRVNAME ": Not a VIA CPU\n");
284 err = platform_driver_register(&via_cputemp_driver);
288 for_each_online_cpu(i) {
289 struct cpuinfo_x86 *c = &cpu_data(i);
294 if (c->x86_model < 0x0a)
297 if (c->x86_model > 0x0f) {
298 printk(KERN_WARNING DRVNAME ": Unknown CPU "
299 "model 0x%x\n", c->x86_model);
303 err = via_cputemp_device_add(i);
305 goto exit_devices_unreg;
307 if (list_empty(&pdev_list)) {
309 goto exit_driver_unreg;
312 register_hotcpu_notifier(&via_cputemp_cpu_notifier);
316 mutex_lock(&pdev_list_mutex);
317 list_for_each_entry_safe(p, n, &pdev_list, list) {
318 platform_device_unregister(p->pdev);
322 mutex_unlock(&pdev_list_mutex);
324 platform_driver_unregister(&via_cputemp_driver);
329 static void __exit via_cputemp_exit(void)
331 struct pdev_entry *p, *n;
333 unregister_hotcpu_notifier(&via_cputemp_cpu_notifier);
334 mutex_lock(&pdev_list_mutex);
335 list_for_each_entry_safe(p, n, &pdev_list, list) {
336 platform_device_unregister(p->pdev);
340 mutex_unlock(&pdev_list_mutex);
341 platform_driver_unregister(&via_cputemp_driver);
344 MODULE_AUTHOR("Harald Welte <HaraldWelte@viatech.com>");
345 MODULE_DESCRIPTION("VIA CPU temperature monitor");
346 MODULE_LICENSE("GPL");
348 module_init(via_cputemp_init)
349 module_exit(via_cputemp_exit)