设备节点-Brief

2019-02-01 14:45:17
燚智能王工

linux创建设备节点——class_creat()

分类： LINUX

从linux内核2.6的某个版本之后，devfs不复存在，udev成为devfs的替代。相比devfs，udev有很多优势，在此就不罗嗦了，提醒一点，udev是应用层的东东，不要试图在内核的配置选项里找到它;加入对udev的支持很简单，以作者所写的一个字符设备驱动为例，在驱动初始化的代码里调用class_create为该设备创建一个class，再为每个设备调用 class_device_create创建对应的设备。大致用法如下：

struct class *myclass = class_create(THIS_MODULE, “my_device_driver”);

class_device_create(myclass, NULL, MKDEV(major_num, 0), NULL, “my_device”);

这样的module被加载时，udev daemon就会自动在/dev下创建my_device设备文件。

class_create()

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linux-2.6.22/include/linux/device.h

struct class *class_create(struct module *owner, const char *name)

class_create - create a struct class structure

@owner: pointer to the module that is to "own" this struct class

@name: pointer to a string for the name of this class.

在/sys/class/下创建类目录

class_device_create()

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linux-2.6.22/include/linux/device.h

struct class_device *class_device_create(struct class *cls,

struct class_device *parent,

dev_t devt,

struct device *device,

const char *fmt, ...)

class_device_create - creates a class device and registers it with sysfs

@cls: pointer to the struct class that this device should be registered to.

@parent: pointer to the parent struct class_device of this new device, if any.

@devt: the dev_t for the char device to be added.

@device: a pointer to a struct device that is assiociated with this class device.

@fmt: string for the class device's namelinux创建设备节点——class_creat() 2012-03-20 13:35:03

分类： LINUX

struct class *myclass = class_create(THIS_MODULE, “my_device_driver”);

class_device_create(myclass, NULL, MKDEV(major_num, 0), NULL, “my_device”);

这样的module被加载时，udev daemon就会自动在/dev下创建my_device设备文件。

class_create()

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linux-2.6.22/include/linux/device.h

struct class *class_create(struct module *owner, const char *name)

class_create - create a struct class structure

@owner: pointer to the module that is to "own" this struct class

@name: pointer to a string for the name of this class.

在/sys/class/下创建类目录

class_device_create()

-------------------------------------------------

linux-2.6.22/include/linux/device.h

struct class_device *class_device_create(struct class *cls,

struct class_device *parent,

dev_t devt,

struct device *device,

const char *fmt, ...)

class_device_create - creates a class device and registers it with sysfs

@cls: pointer to the struct class that this device should be registered to.

@parent: pointer to the parent struct class_device of this new device, if any.

@devt: the dev_t for the char device to be added.

@device: a pointer to a struct device that is assiociated with this class device.

@fmt: string for the class device's name

设备节点-Brief

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