drivers/hwmon/hwmon.c - kernel/quantenna - Git at Google

 /*
  * 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");
	/*
	* 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");