这样,加载模块的时候,用户空间中的udev会自动响应 device_create(…)函数,去/sysfs下寻找对应的类从而创建设备节点。 注意,在2.6较早的内核版本中,device_create(…)函数名称不同,是class_device_create(…),所以在新的内核中编译以前的模块程序有时会报错,就是因为函数名称 不同,而且里面的参数设置
printk("Failed at class_create().Please exec [mknod] before operate the device/n"); } else { device_create(hello_class, NULL, devnum,NULL, devicename); } open_count = 0; langtype = english; inbuffer = (char *)kmalloc(IN_BUF_LEN, GFP_KERNEL); outbuffer = (char *)kmalloc(OUT_...
printk("Failed at class_create().Please exec [mknod] before operate the device/n"); } else { device_create(hello_class, NULL, devnum,NULL, devicename); } open_count = 0; langtype = english; inbuffer = (char *)kmalloc(IN_BUF_LEN, GFP_KERNEL); outbuffer = (char *)kmalloc(OUT_...
device_create_file不做详细解析,因为devices本来就是/sys文件系统中的重要概念 关键是devtmpfs_create_node 什么是Devtmpfs 的概念 Devtmpfs lets the kernel create a tmpfs very early at kernel initialization , before any driver core device is...
struct device_driver *driver; //设备使用的驱动 struct klist_node knode_class;//连接到设备类的klist struct class *class; //所属设备类 ... }; //所在文件/kernel/drivers/base/base.h struct device_private { struct klist klist_children
Linux Kernel设备驱动模型之 平台设备注册 /** * platform_device_register_full - add a platform-level device with * resources and platform-specific data * * @pdevinfo: data used to create device * * Returns &struct platform_device pointer on success, or ERR_PTR() on error....
device_create_file不做详细解析,因为devices本来就是/sys文件系统中的重要概念 关键是devtmpfs_create_node 什么是Devtmpfs 的概念 Devtmpfs lets the kernel create a tmpfs very early at kernel initialization , before any driver core device is registered . Every device with a major / minor will have a ...
_device_tree();// arch/arm/kernel/setup.c__unflatten_device_tree(initial_boot_params,NULL,&of_root,early_init_dt_alloc_memory_arch,false);// drivers/of/fdt.c/* First pass, scan for size */size=unflatten_dt_nodes(blob,NULL,dad,NULL);/* Allocate memory for the expanded device tree ...
使用DEVICE_ATTR,可以实现驱动在sys目录自动创建文件,我们只需要实现show和store函数即可. 诺谦 2018/10/22 3.5K0 驱动基础——字符设备1 linuxnode.jskernelflash 使用命令建立一个设备 s 驱动代码 #include <linux/module.h> #include <linux/kernel.h> #include <linux/init.h> #include <linux/fs.h> #...
(GFP_KERNEL);if(!mydrv_queue){pr_err("mydrv: request queue creation failed\n");gotoerr_queue;}/* Set request function */blk_queue_make_request(mydrv_queue,mydrv_request);/* Initialize volumes */if(!init_volumes(&mydrv_queue,&disk)){pr_err("mydrv: volume initialization failed\n");...