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-rw-r--r--drivers/hwmon/hwmon.c287
1 files changed, 287 insertions, 0 deletions
diff --git a/drivers/hwmon/hwmon.c b/drivers/hwmon/hwmon.c
new file mode 100644
index 000000000..a26c385a4
--- /dev/null
+++ b/drivers/hwmon/hwmon.c
@@ -0,0 +1,287 @@
+/*
+ * hwmon.c - part of lm_sensors, Linux kernel modules for hardware monitoring
+ *
+ * This file defines the sysfs class "hwmon", for use by sensors drivers.
+ *
+ * Copyright (C) 2005 Mark M. Hoffman <mhoffman@lightlink.com>
+ *
+ * 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.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/kdev_t.h>
+#include <linux/idr.h>
+#include <linux/hwmon.h>
+#include <linux/gfp.h>
+#include <linux/spinlock.h>
+#include <linux/pci.h>
+#include <linux/string.h>
+
+#define HWMON_ID_PREFIX "hwmon"
+#define HWMON_ID_FORMAT HWMON_ID_PREFIX "%d"
+
+struct hwmon_device {
+ const char *name;
+ struct device dev;
+};
+#define to_hwmon_device(d) container_of(d, struct hwmon_device, dev)
+
+static ssize_t
+show_name(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ return sprintf(buf, "%s\n", to_hwmon_device(dev)->name);
+}
+static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
+
+static struct attribute *hwmon_dev_attrs[] = {
+ &dev_attr_name.attr,
+ NULL
+};
+
+static umode_t hwmon_dev_name_is_visible(struct kobject *kobj,
+ struct attribute *attr, int n)
+{
+ struct device *dev = container_of(kobj, struct device, kobj);
+
+ if (to_hwmon_device(dev)->name == NULL)
+ return 0;
+
+ return attr->mode;
+}
+
+static struct attribute_group hwmon_dev_attr_group = {
+ .attrs = hwmon_dev_attrs,
+ .is_visible = hwmon_dev_name_is_visible,
+};
+
+static const struct attribute_group *hwmon_dev_attr_groups[] = {
+ &hwmon_dev_attr_group,
+ NULL
+};
+
+static void hwmon_dev_release(struct device *dev)
+{
+ kfree(to_hwmon_device(dev));
+}
+
+static struct class hwmon_class = {
+ .name = "hwmon",
+ .owner = THIS_MODULE,
+ .dev_groups = hwmon_dev_attr_groups,
+ .dev_release = hwmon_dev_release,
+};
+
+static DEFINE_IDA(hwmon_ida);
+
+/**
+ * hwmon_device_register_with_groups - register w/ hwmon
+ * @dev: the parent device
+ * @name: hwmon name attribute
+ * @drvdata: driver data to attach to created device
+ * @groups: List of attribute groups to create
+ *
+ * hwmon_device_unregister() must be called when the device is no
+ * longer needed.
+ *
+ * Returns the pointer to the new device.
+ */
+struct device *
+hwmon_device_register_with_groups(struct device *dev, const char *name,
+ void *drvdata,
+ const struct attribute_group **groups)
+{
+ struct hwmon_device *hwdev;
+ int err, id;
+
+ /* Do not accept invalid characters in hwmon name attribute */
+ if (name && (!strlen(name) || strpbrk(name, "-* \t\n")))
+ return ERR_PTR(-EINVAL);
+
+ id = ida_simple_get(&hwmon_ida, 0, 0, GFP_KERNEL);
+ if (id < 0)
+ return ERR_PTR(id);
+
+ hwdev = kzalloc(sizeof(*hwdev), GFP_KERNEL);
+ if (hwdev == NULL) {
+ err = -ENOMEM;
+ goto ida_remove;
+ }
+
+ hwdev->name = name;
+ hwdev->dev.class = &hwmon_class;
+ hwdev->dev.parent = dev;
+ hwdev->dev.groups = groups;
+ hwdev->dev.of_node = dev ? dev->of_node : NULL;
+ dev_set_drvdata(&hwdev->dev, drvdata);
+ dev_set_name(&hwdev->dev, HWMON_ID_FORMAT, id);
+ err = device_register(&hwdev->dev);
+ if (err)
+ goto free;
+
+ return &hwdev->dev;
+
+free:
+ kfree(hwdev);
+ida_remove:
+ ida_simple_remove(&hwmon_ida, id);
+ return ERR_PTR(err);
+}
+EXPORT_SYMBOL_GPL(hwmon_device_register_with_groups);
+
+/**
+ * hwmon_device_register - register w/ hwmon
+ * @dev: the device to register
+ *
+ * hwmon_device_unregister() must be called when the device is no
+ * longer needed.
+ *
+ * Returns the pointer to the new device.
+ */
+struct device *hwmon_device_register(struct device *dev)
+{
+ return hwmon_device_register_with_groups(dev, NULL, NULL, NULL);
+}
+EXPORT_SYMBOL_GPL(hwmon_device_register);
+
+/**
+ * hwmon_device_unregister - removes the previously registered class device
+ *
+ * @dev: the class device to destroy
+ */
+void hwmon_device_unregister(struct device *dev)
+{
+ int id;
+
+ if (likely(sscanf(dev_name(dev), HWMON_ID_FORMAT, &id) == 1)) {
+ device_unregister(dev);
+ ida_simple_remove(&hwmon_ida, id);
+ } else
+ dev_dbg(dev->parent,
+ "hwmon_device_unregister() failed: bad class ID!\n");
+}
+EXPORT_SYMBOL_GPL(hwmon_device_unregister);
+
+static void devm_hwmon_release(struct device *dev, void *res)
+{
+ struct device *hwdev = *(struct device **)res;
+
+ hwmon_device_unregister(hwdev);
+}
+
+/**
+ * devm_hwmon_device_register_with_groups - register w/ hwmon
+ * @dev: the parent device
+ * @name: hwmon name attribute
+ * @drvdata: driver data to attach to created device
+ * @groups: List of attribute groups to create
+ *
+ * Returns the pointer to the new device. The new device is automatically
+ * unregistered with the parent device.
+ */
+struct device *
+devm_hwmon_device_register_with_groups(struct device *dev, const char *name,
+ void *drvdata,
+ const struct attribute_group **groups)
+{
+ struct device **ptr, *hwdev;
+
+ if (!dev)
+ return ERR_PTR(-EINVAL);
+
+ ptr = devres_alloc(devm_hwmon_release, sizeof(*ptr), GFP_KERNEL);
+ if (!ptr)
+ return ERR_PTR(-ENOMEM);
+
+ hwdev = hwmon_device_register_with_groups(dev, name, drvdata, groups);
+ if (IS_ERR(hwdev))
+ goto error;
+
+ *ptr = hwdev;
+ devres_add(dev, ptr);
+ return hwdev;
+
+error:
+ devres_free(ptr);
+ return hwdev;
+}
+EXPORT_SYMBOL_GPL(devm_hwmon_device_register_with_groups);
+
+static int devm_hwmon_match(struct device *dev, void *res, void *data)
+{
+ struct device **hwdev = res;
+
+ return *hwdev == data;
+}
+
+/**
+ * devm_hwmon_device_unregister - removes a previously registered hwmon device
+ *
+ * @dev: the parent device of the device to unregister
+ */
+void devm_hwmon_device_unregister(struct device *dev)
+{
+ WARN_ON(devres_release(dev, devm_hwmon_release, devm_hwmon_match, dev));
+}
+EXPORT_SYMBOL_GPL(devm_hwmon_device_unregister);
+
+static void __init hwmon_pci_quirks(void)
+{
+#if defined CONFIG_X86 && defined CONFIG_PCI
+ struct pci_dev *sb;
+ u16 base;
+ u8 enable;
+
+ /* Open access to 0x295-0x296 on MSI MS-7031 */
+ sb = pci_get_device(PCI_VENDOR_ID_ATI, 0x436c, NULL);
+ if (sb) {
+ if (sb->subsystem_vendor == 0x1462 && /* MSI */
+ sb->subsystem_device == 0x0031) { /* MS-7031 */
+ pci_read_config_byte(sb, 0x48, &enable);
+ pci_read_config_word(sb, 0x64, &base);
+
+ if (base == 0 && !(enable & BIT(2))) {
+ dev_info(&sb->dev,
+ "Opening wide generic port at 0x295\n");
+ pci_write_config_word(sb, 0x64, 0x295);
+ pci_write_config_byte(sb, 0x48,
+ enable | BIT(2));
+ }
+ }
+ pci_dev_put(sb);
+ }
+#endif
+}
+
+static int __init hwmon_init(void)
+{
+ int err;
+
+ hwmon_pci_quirks();
+
+ err = class_register(&hwmon_class);
+ if (err) {
+ pr_err("couldn't register hwmon sysfs class\n");
+ return err;
+ }
+ return 0;
+}
+
+static void __exit hwmon_exit(void)
+{
+ class_unregister(&hwmon_class);
+}
+
+subsys_initcall(hwmon_init);
+module_exit(hwmon_exit);
+
+MODULE_AUTHOR("Mark M. Hoffman <mhoffman@lightlink.com>");
+MODULE_DESCRIPTION("hardware monitoring sysfs/class support");
+MODULE_LICENSE("GPL");
+