hwmon: New coretemp driver
authorRudolf Marek <r.marek@assembler.cz>
Tue, 8 May 2007 15:22:02 +0000 (17:22 +0200)
committerJean Delvare <khali@hyperion.delvare>
Tue, 8 May 2007 15:22:02 +0000 (17:22 +0200)
Add the support for the digital temperature sensor found in recent
Intel Core CPUs.

Signed-off-by: Rudolf Marek <r.marek@assembler.cz>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
MAINTAINERS
drivers/hwmon/Kconfig
drivers/hwmon/Makefile
drivers/hwmon/coretemp.c [new file with mode: 0644]

index a328862731c6fa710dfb313abc0d27063d682bf2..1561f33e15b994b8e1983250a2e97d202747e7f0 100644 (file)
@@ -1031,6 +1031,12 @@ P:       Simon Arlott
 M:     cxacru@fire.lp0.eu
 S:     Maintained
 
+CORETEMP HARDWARE MONITORING DRIVER
+P:     Rudolf Marek
+M:     r.marek@assembler.cz
+L:     lm-sensors@lm-sensors.org
+S:     Maintained
+
 COSA/SRP SYNC SERIAL DRIVER
 P:     Jan "Yenya" Kasprzak
 M:     kas@fi.muni.cz
index 659a2abb3e90ff7a7ed114f22d4f083b5f654650..e488d691da4a8d8199e4643e7c96692f93abb89a 100644 (file)
@@ -229,6 +229,14 @@ config SENSORS_GL520SM
          This driver can also be built as a module.  If so, the module
          will be called gl520sm.
 
+config SENSORS_CORETEMP
+       tristate "Intel Core (2) Duo/Solo temperature sensor"
+       depends on HWMON && X86 && EXPERIMENTAL
+       help
+         If you say yes here you get support for the temperature
+         sensor inside your CPU. Supported all are all known variants
+         of Intel Core family.
+
 config SENSORS_IT87
        tristate "ITE IT87xx and compatibles"
        depends on HWMON && I2C
index bbbe86bf5da1e73b6d6055a040bce4263fc49e50..33780678bd4b877e0bca851f48902c74bebd5cb6 100644 (file)
@@ -22,6 +22,7 @@ obj-$(CONFIG_SENSORS_ADM1031) += adm1031.o
 obj-$(CONFIG_SENSORS_ADM9240)  += adm9240.o
 obj-$(CONFIG_SENSORS_AMS)      += ams/
 obj-$(CONFIG_SENSORS_ATXP1)    += atxp1.o
+obj-$(CONFIG_SENSORS_CORETEMP) += coretemp.o
 obj-$(CONFIG_SENSORS_DS1621)   += ds1621.o
 obj-$(CONFIG_SENSORS_F71805F)  += f71805f.o
 obj-$(CONFIG_SENSORS_FSCHER)   += fscher.o
diff --git a/drivers/hwmon/coretemp.c b/drivers/hwmon/coretemp.c
new file mode 100644 (file)
index 0000000..03b1f65
--- /dev/null
@@ -0,0 +1,406 @@
+/*
+ * coretemp.c - Linux kernel module for hardware monitoring
+ *
+ * Copyright (C) 2007 Rudolf Marek <r.marek@assembler.cz>
+ *
+ * Inspired from many hwmon drivers
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301 USA.
+ */
+
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/jiffies.h>
+#include <linux/hwmon.h>
+#include <linux/sysfs.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/err.h>
+#include <linux/mutex.h>
+#include <linux/list.h>
+#include <linux/platform_device.h>
+#include <linux/cpu.h>
+#include <asm/msr.h>
+#include <asm/processor.h>
+
+#define DRVNAME        "coretemp"
+
+typedef enum { SHOW_TEMP, SHOW_TJMAX, SHOW_LABEL, SHOW_NAME } SHOW;
+
+/*
+ * Functions declaration
+ */
+
+static struct coretemp_data *coretemp_update_device(struct device *dev);
+
+struct coretemp_data {
+       struct class_device *class_dev;
+       struct mutex update_lock;
+       const char *name;
+       u32 id;
+       char valid;             /* zero until following fields are valid */
+       unsigned long last_updated;     /* in jiffies */
+       int temp;
+       int tjmax;
+       u8 alarm;
+};
+
+static struct coretemp_data *coretemp_update_device(struct device *dev);
+
+/*
+ * Sysfs stuff
+ */
+
+static ssize_t show_name(struct device *dev, struct device_attribute
+                         *devattr, char *buf)
+{
+       int ret;
+       struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+       struct coretemp_data *data = dev_get_drvdata(dev);
+
+       if (attr->index == SHOW_NAME)
+               ret = sprintf(buf, "%s\n", data->name);
+       else    /* show label */
+               ret = sprintf(buf, "Core %d\n", data->id);
+       return ret;
+}
+
+static ssize_t show_alarm(struct device *dev, struct device_attribute
+                         *devattr, char *buf)
+{
+       struct coretemp_data *data = coretemp_update_device(dev);
+       /* read the Out-of-spec log, never clear */
+       return sprintf(buf, "%d\n", data->alarm);
+}
+
+static ssize_t show_temp(struct device *dev,
+                        struct device_attribute *devattr, char *buf)
+{
+       struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+       struct coretemp_data *data = coretemp_update_device(dev);
+       int err;
+
+       if (attr->index == SHOW_TEMP)
+               err = data->valid ? sprintf(buf, "%d\n", data->temp) : -EAGAIN;
+       else
+               err = sprintf(buf, "%d\n", data->tjmax);
+
+       return err;
+}
+
+static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL,
+                         SHOW_TEMP);
+static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO, show_temp, NULL,
+                         SHOW_TJMAX);
+static DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL);
+static SENSOR_DEVICE_ATTR(temp1_label, S_IRUGO, show_name, NULL, SHOW_LABEL);
+static SENSOR_DEVICE_ATTR(name, S_IRUGO, show_name, NULL, SHOW_NAME);
+
+static struct attribute *coretemp_attributes[] = {
+       &sensor_dev_attr_name.dev_attr.attr,
+       &sensor_dev_attr_temp1_label.dev_attr.attr,
+       &dev_attr_temp1_crit_alarm.attr,
+       &sensor_dev_attr_temp1_input.dev_attr.attr,
+       &sensor_dev_attr_temp1_crit.dev_attr.attr,
+       NULL
+};
+
+static const struct attribute_group coretemp_group = {
+       .attrs = coretemp_attributes,
+};
+
+static struct coretemp_data *coretemp_update_device(struct device *dev)
+{
+       struct coretemp_data *data = dev_get_drvdata(dev);
+
+       mutex_lock(&data->update_lock);
+
+       if (!data->valid || time_after(jiffies, data->last_updated + HZ)) {
+               u32 eax, edx;
+
+               data->valid = 0;
+               rdmsr_on_cpu(data->id, MSR_IA32_THERM_STATUS, &eax, &edx);
+               data->alarm = (eax >> 5) & 1;
+               /* update only if data has been valid */
+               if (eax & 0x80000000) {
+                       data->temp = data->tjmax - (((eax >> 16)
+                                                       & 0x7f) * 1000);
+                       data->valid = 1;
+               } else {
+                       dev_dbg(dev, "Temperature data invalid (0x%x)\n", eax);
+               }
+               data->last_updated = jiffies;
+       }
+
+       mutex_unlock(&data->update_lock);
+       return data;
+}
+
+static int __devinit coretemp_probe(struct platform_device *pdev)
+{
+       struct coretemp_data *data;
+       struct cpuinfo_x86 *c = &(cpu_data)[pdev->id];
+       int err;
+       u32 eax, edx;
+
+       if (!(data = kzalloc(sizeof(struct coretemp_data), GFP_KERNEL))) {
+               err = -ENOMEM;
+               dev_err(&pdev->dev, "Out of memory\n");
+               goto exit;
+       }
+
+       data->id = pdev->id;
+       data->name = "coretemp";
+       mutex_init(&data->update_lock);
+       /* Tjmax default is 100 degrees C */
+       data->tjmax = 100000;
+
+       /* test if we can access the THERM_STATUS MSR */
+       err = rdmsr_safe_on_cpu(data->id, MSR_IA32_THERM_STATUS, &eax, &edx);
+       if (err) {
+               dev_err(&pdev->dev,
+                       "Unable to access THERM_STATUS MSR, giving up\n");
+               goto exit_free;
+       }
+
+       /* Some processors have Tjmax 85 following magic should detect it
+          Intel won't disclose the information without signed NDA, but
+          individuals cannot sign it. Catch(ed) 22.
+       */
+
+       if (((c->x86_model == 0xf) && (c->x86_mask > 3)) ||
+               (c->x86_model == 0xe))  {
+               err = rdmsr_safe_on_cpu(data->id, 0xee, &eax, &edx);
+               if (err) {
+                       dev_warn(&pdev->dev,
+                                "Unable to access MSR 0xEE, Tjmax left at %d "
+                                "degrees C\n", data->tjmax/1000);
+               } else if (eax & 0x40000000) {
+                       data->tjmax = 85000;
+               }
+       }
+
+       platform_set_drvdata(pdev, data);
+
+       if ((err = sysfs_create_group(&pdev->dev.kobj, &coretemp_group)))
+               goto exit_free;
+
+       data->class_dev = hwmon_device_register(&pdev->dev);
+       if (IS_ERR(data->class_dev)) {
+               err = PTR_ERR(data->class_dev);
+               dev_err(&pdev->dev, "Class registration failed (%d)\n",
+                       err);
+               goto exit_class;
+       }
+
+       return 0;
+
+exit_class:
+       sysfs_remove_group(&pdev->dev.kobj, &coretemp_group);
+exit_free:
+       kfree(data);
+exit:
+       return err;
+}
+
+static int __devexit coretemp_remove(struct platform_device *pdev)
+{
+       struct coretemp_data *data = platform_get_drvdata(pdev);
+
+       hwmon_device_unregister(data->class_dev);
+       sysfs_remove_group(&pdev->dev.kobj, &coretemp_group);
+       platform_set_drvdata(pdev, NULL);
+       kfree(data);
+       return 0;
+}
+
+static struct platform_driver coretemp_driver = {
+       .driver = {
+               .owner = THIS_MODULE,
+               .name = DRVNAME,
+       },
+       .probe = coretemp_probe,
+       .remove = __devexit_p(coretemp_remove),
+};
+
+struct pdev_entry {
+       struct list_head list;
+       struct platform_device *pdev;
+       unsigned int cpu;
+};
+
+static LIST_HEAD(pdev_list);
+static DEFINE_MUTEX(pdev_list_mutex);
+
+static int __cpuinit coretemp_device_add(unsigned int cpu)
+{
+       int err;
+       struct platform_device *pdev;
+       struct pdev_entry *pdev_entry;
+
+       pdev = platform_device_alloc(DRVNAME, cpu);
+       if (!pdev) {
+               err = -ENOMEM;
+               printk(KERN_ERR DRVNAME ": Device allocation failed\n");
+               goto exit;
+       }
+
+       pdev_entry = kzalloc(sizeof(struct pdev_entry), GFP_KERNEL);
+       if (!pdev_entry) {
+               err = -ENOMEM;
+               goto exit_device_put;
+       }
+
+       err = platform_device_add(pdev);
+       if (err) {
+               printk(KERN_ERR DRVNAME ": Device addition failed (%d)\n",
+                      err);
+               goto exit_device_free;
+       }
+
+       pdev_entry->pdev = pdev;
+       pdev_entry->cpu = cpu;
+       mutex_lock(&pdev_list_mutex);
+       list_add_tail(&pdev_entry->list, &pdev_list);
+       mutex_unlock(&pdev_list_mutex);
+
+       return 0;
+
+exit_device_free:
+       kfree(pdev_entry);
+exit_device_put:
+       platform_device_put(pdev);
+exit:
+       return err;
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+void coretemp_device_remove(unsigned int cpu)
+{
+       struct pdev_entry *p, *n;
+       mutex_lock(&pdev_list_mutex);
+       list_for_each_entry_safe(p, n, &pdev_list, list) {
+               if (p->cpu == cpu) {
+                       platform_device_unregister(p->pdev);
+                       list_del(&p->list);
+                       kfree(p);
+               }
+       }
+       mutex_unlock(&pdev_list_mutex);
+}
+
+static int coretemp_cpu_callback(struct notifier_block *nfb,
+                                unsigned long action, void *hcpu)
+{
+       unsigned int cpu = (unsigned long) hcpu;
+
+       switch (action) {
+       case CPU_ONLINE:
+               coretemp_device_add(cpu);
+               break;
+       case CPU_DEAD:
+               coretemp_device_remove(cpu);
+               break;
+       }
+       return NOTIFY_OK;
+}
+
+static struct notifier_block __cpuinitdata coretemp_cpu_notifier = {
+       .notifier_call = coretemp_cpu_callback,
+};
+#endif                         /* !CONFIG_HOTPLUG_CPU */
+
+static int __init coretemp_init(void)
+{
+       int i, err = -ENODEV;
+       struct pdev_entry *p, *n;
+
+       printk(KERN_NOTICE DRVNAME ": This driver uses undocumented features "
+               "of Core CPU. Temperature might be wrong!\n");
+
+       /* quick check if we run Intel */
+       if (cpu_data[0].x86_vendor != X86_VENDOR_INTEL)
+               goto exit;
+
+       err = platform_driver_register(&coretemp_driver);
+       if (err)
+               goto exit;
+
+       for_each_online_cpu(i) {
+               struct cpuinfo_x86 *c = &(cpu_data)[i];
+
+               /* check if family 6, models e, f */
+               if ((c->cpuid_level < 0) || (c->x86 != 0x6) ||
+                   !((c->x86_model == 0xe) || (c->x86_model == 0xf))) {
+
+                       /* supported CPU not found, but report the unknown
+                          family 6 CPU */
+                       if ((c->x86 == 0x6) && (c->x86_model > 0xf))
+                               printk(KERN_WARNING DRVNAME ": Unknown CPU "
+                                       "model %x\n", c->x86_model);
+                       continue;
+               }
+
+               err = coretemp_device_add(i);
+               if (err)
+                       goto exit_devices_unreg;
+       }
+       if (list_empty(&pdev_list)) {
+               err = -ENODEV;
+               goto exit_driver_unreg;
+       }
+
+#ifdef CONFIG_HOTPLUG_CPU
+       register_hotcpu_notifier(&coretemp_cpu_notifier);
+#endif
+       return 0;
+
+exit_devices_unreg:
+       mutex_lock(&pdev_list_mutex);
+       list_for_each_entry_safe(p, n, &pdev_list, list) {
+               platform_device_unregister(p->pdev);
+               list_del(&p->list);
+               kfree(p);
+       }
+       mutex_unlock(&pdev_list_mutex);
+exit_driver_unreg:
+       platform_driver_unregister(&coretemp_driver);
+exit:
+       return err;
+}
+
+static void __exit coretemp_exit(void)
+{
+       struct pdev_entry *p, *n;
+#ifdef CONFIG_HOTPLUG_CPU
+       unregister_hotcpu_notifier(&coretemp_cpu_notifier);
+#endif
+       mutex_lock(&pdev_list_mutex);
+       list_for_each_entry_safe(p, n, &pdev_list, list) {
+               platform_device_unregister(p->pdev);
+               list_del(&p->list);
+               kfree(p);
+       }
+       mutex_unlock(&pdev_list_mutex);
+       platform_driver_unregister(&coretemp_driver);
+}
+
+MODULE_AUTHOR("Rudolf Marek <r.marek@assembler.cz>");
+MODULE_DESCRIPTION("Intel Core temperature monitor");
+MODULE_LICENSE("GPL");
+
+module_init(coretemp_init)
+module_exit(coretemp_exit)