This is a driver for the on-die digital temperature sensor of
VIA's recent CPU models.
Signed-off-by: Harald Welte <HaraldWelte at viatech.com>
---
drivers/hwmon/Kconfig | 8 +
drivers/hwmon/Makefile | 1 +
drivers/hwmon/via-cputemp.c | 354 +++++++++++++++++++++++++++++++++++++++++++
3 files changed, 363 insertions(+), 0 deletions(-)
create mode 100644 drivers/hwmon/via-cputemp.c
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index d73f5f4..e863833 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -787,6 +787,14 @@ config SENSORS_THMC50
This driver can also be built as a module. If so, the module
will be called thmc50.
+config SENSORS_VIA_CPUTEMP
+ tristate "VIA CPU temperature sensor"
+ depends on X86
+ help
+ If you say yes here you get support for the temperature
+ sensor inside your CPU. Supported all are all known variants
+ of the VIA C7 and Nano.
+
config SENSORS_VIA686A
tristate "VIA686A"
depends on PCI
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index 0ae2698..3edf7fa 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -82,6 +82,7 @@ obj-$(CONFIG_SENSORS_SMSC47B397)+= smsc47b397.o
obj-$(CONFIG_SENSORS_SMSC47M1) += smsc47m1.o
obj-$(CONFIG_SENSORS_SMSC47M192)+= smsc47m192.o
obj-$(CONFIG_SENSORS_THMC50) += thmc50.o
+obj-$(CONFIG_SENSORS_VIA_CPUTEMP)+= via-cputemp.o
obj-$(CONFIG_SENSORS_VIA686A) += via686a.o
obj-$(CONFIG_SENSORS_VT1211) += vt1211.o
obj-$(CONFIG_SENSORS_VT8231) += vt8231.o
diff --git a/drivers/hwmon/via-cputemp.c b/drivers/hwmon/via-cputemp.c
new file mode 100644
index 0000000..1032355
--- /dev/null
+++ b/drivers/hwmon/via-cputemp.c
@@ -0,0 +1,354 @@
+/*
+ * via-cputemp.c - Driver for VIA CPU core temperature monitoring
+ * Copyright (C) 2009 VIA Technologies, Inc.
+ *
+ * based on existing coretemp.c, which is
+ *
+ * Copyright (C) 2007 Rudolf Marek <r.marek at assembler.cz>
+ *
+ * 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 "via-cputemp"
+
+typedef enum { SHOW_TEMP, SHOW_LABEL, SHOW_NAME } SHOW;
+
+/*
+ * Functions declaration
+ */
+
+struct via_cputemp_data {
+ struct device *hwmon_dev;
+ const char *name;
+ u32 id;
+ u32 msr;
+};
+
+/*
+ * 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 via_cputemp_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_temp(struct device *dev,
+ struct device_attribute *devattr, char *buf)
+{
+ struct via_cputemp_data *data = dev_get_drvdata(dev);
+ u32 eax, edx;
+ int err;
+
+ err = rdmsr_safe_on_cpu(data->id, data->msr, &eax, &edx);
+ if (err)
+ return -EAGAIN;
+
+ err = sprintf(buf, "%d\n", eax & 0xffffff);
+
+ return err;
+}
+
+static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL,
+ SHOW_TEMP);
+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 *via_cputemp_attributes[] = {
+ &sensor_dev_attr_name.dev_attr.attr,
+ &sensor_dev_attr_temp1_label.dev_attr.attr,
+ &sensor_dev_attr_temp1_input.dev_attr.attr,
+ NULL
+};
+
+static const struct attribute_group via_cputemp_group = {
+ .attrs = via_cputemp_attributes,
+};
+
+static int __devinit via_cputemp_probe(struct platform_device *pdev)
+{
+ struct via_cputemp_data *data;
+ struct cpuinfo_x86 *c = &cpu_data(pdev->id);
+ int err;
+ u32 eax, edx;
+
+ if (!(data = kzalloc(sizeof(struct via_cputemp_data), GFP_KERNEL))) {
+ err = -ENOMEM;
+ dev_err(&pdev->dev, "Out of memory\n");
+ goto exit;
+ }
+
+ data->id = pdev->id;
+ data->name = "via-cputemp";
+
+ switch (c->x86_model) {
+ case 0xA:
+ /* C7 A */
+ case 0xD:
+ /* C7 D */
+ data->msr = 0x1169;
+ break;
+ case 0xF:
+ /* Nano */
+ data->msr = 0x1423;
+ break;
+ default:
+ err = -ENODEV;
+ goto exit_free;
+ }
+
+ /* test if we can access the TEMPERATURE MSR */
+ err = rdmsr_safe_on_cpu(data->id, data->msr, &eax, &edx);
+ if (err) {
+ dev_err(&pdev->dev,
+ "Unable to access TEMPERATURE MSR, giving up\n");
+ goto exit_free;
+ }
+
+ platform_set_drvdata(pdev, data);
+
+ if ((err = sysfs_create_group(&pdev->dev.kobj, &via_cputemp_group)))
+ goto exit_free;
+
+ data->hwmon_dev = hwmon_device_register(&pdev->dev);
+ if (IS_ERR(data->hwmon_dev)) {
+ err = PTR_ERR(data->hwmon_dev);
+ dev_err(&pdev->dev, "Class registration failed (%d)\n",
+ err);
+ goto exit_class;
+ }
+
+ return 0;
+
+exit_class:
+ sysfs_remove_group(&pdev->dev.kobj, &via_cputemp_group);
+exit_free:
+ kfree(data);
+exit:
+ return err;
+}
+
+static int __devexit via_cputemp_remove(struct platform_device *pdev)
+{
+ struct via_cputemp_data *data = platform_get_drvdata(pdev);
+
+ hwmon_device_unregister(data->hwmon_dev);
+ sysfs_remove_group(&pdev->dev.kobj, &via_cputemp_group);
+ platform_set_drvdata(pdev, NULL);
+ kfree(data);
+ return 0;
+}
+
+static struct platform_driver via_cputemp_driver = {
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = DRVNAME,
+ },
+ .probe = via_cputemp_probe,
+ .remove = __devexit_p(via_cputemp_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 via_cputemp_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
+static void via_cputemp_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 __cpuinit via_cputemp_cpu_callback(struct notifier_block *nfb,
+ unsigned long action, void *hcpu)
+{
+ unsigned int cpu = (unsigned long) hcpu;
+
+ switch (action) {
+ case CPU_ONLINE:
+ case CPU_DOWN_FAILED:
+ via_cputemp_device_add(cpu);
+ break;
+ case CPU_DOWN_PREPARE:
+ via_cputemp_device_remove(cpu);
+ break;
+ }
+ return NOTIFY_OK;
+}
+
+static struct notifier_block via_cputemp_cpu_notifier __refdata = {
+ .notifier_call = via_cputemp_cpu_callback,
+};
+#endif /* !CONFIG_HOTPLUG_CPU */
+
+static int __init via_cputemp_init(void)
+{
+ int i, err = -ENODEV;
+ struct pdev_entry *p, *n;
+
+ if (cpu_data(0).x86_vendor != X86_VENDOR_CENTAUR) {
+ printk(KERN_DEBUG "not a VIA CPU\n");
+ goto exit;
+ }
+
+ err = platform_driver_register(&via_cputemp_driver);
+ if (err)
+ goto exit;
+
+ for_each_online_cpu(i) {
+ struct cpuinfo_x86 *c = &cpu_data(i);
+
+ if (c->x86 != 6)
+ continue;
+
+ if (c->x86_model < 0x0a)
+ continue;
+
+ if (c->x86_model > 0x0f) {
+ printk(KERN_WARNING DRVNAME ": Unknown CPU "
+ "model %x\n", c->x86_model);
+ continue;
+ }
+
+ err = via_cputemp_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(&via_cputemp_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(&via_cputemp_driver);
+exit:
+ return err;
+}
+
+static void __exit via_cputemp_exit(void)
+{
+ struct pdev_entry *p, *n;
+#ifdef CONFIG_HOTPLUG_CPU
+ unregister_hotcpu_notifier(&via_cputemp_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(&via_cputemp_driver);
+}
+
+MODULE_AUTHOR("Harald Welte <HaraldWelte at viatech.com>");
+MODULE_DESCRIPTION("VIA CPU temperature monitor");
+MODULE_LICENSE("GPL");
+
+module_init(via_cputemp_init)
+module_exit(via_cputemp_exit)
--
1.6.3.1
