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
)