static int startup(void)
{
dev_t dev = MKDEV(major, minor);
int result = 0;
memory = NULL;
printk(KERN_INFO "hello: startup\n");
if (! request_region(lpt_port, SHORT_NR_PORTS, "MY_LPT")) {
printk(KERN_INFO "hello: can't get I/O mem address 0x%lx\n", lpt_port);
return -ENODEV;
}
printk(KERN_WARNING "hello: request_region: port 0x%lx hooked\n", lpt_port);
// get a driver number
if (major) {
dev = MKDEV(major, minor);
result = register_chrdev_region(dev, 1, "hello");
} else {
result = alloc_chrdev_region(&dev, minor, 1, "hello");
major = MAJOR(dev);
}
if (result < 0) {
printk(KERN_WARNING "hello: can't get version %d:%d\n", major, minor);
return result;
}
// Initialize the device.
my_cdev = cdev_alloc();
if(!my_cdev) {
printk(KERN_WARNING "hello: cdev_alloc failed");
return -1;
}
my_cdev->ops = &my_ops;
if(cdev_add(my_cdev, dev, 1) < 0) {
printk(KERN_WARNING "hello: cdev_add failed");
return -1;
}
hello_create_proc(); // proc debugging
printk(KERN_WARNING "hello: got version %d:%d\n", major, minor);
printk(KERN_WARNING "hello: my_cdev allocated\n");
printk(KERN_WARNING "hello: my_cdev added\n");
return 0;
}
/*模块加载方法*/
static int __init hello_init(void){
int err = -1;
dev_t dev = 0;
struct device* temp = NULL;
printk(KERN_ALERT"Initializing hello device.\n");
/*动态分配主设备和从设备号*/
err = alloc_chrdev_region(&dev, 0, 1, HELLO_DEVICE_NODE_NAME);
if(err < 0) {
printk(KERN_ALERT"Failed to alloc char dev region.\n");
goto fail;
}
hello_major = MAJOR(dev);
hello_minor = MINOR(dev);
/* 分配hello设备结构体变量 */
hello_dev = kmalloc(sizeof(struct hello_android_dev), GFP_KERNEL);
if(!hello_dev) {
err = -ENOMEM;
printk(KERN_ALERT"Failed to alloc hello_dev.\n");
goto unregister;
}
/*初始化设备*/
err = __hello_setup_dev(hello_dev);
if(err) {
printk(KERN_ALERT"Failed to setup dev: %d.\n", err);
goto cleanup;
}
#ifdef HELLO_DEVFS_BUILD
/*在/sys/class/目录下创建设备类别目录hello*/
hello_class = class_create(THIS_MODULE, HELLO_DEVICE_CLASS_NAME);
if(IS_ERR(hello_class)) {
err = PTR_ERR(hello_class);
printk(KERN_ALERT"Failed to create hello class.\n");
goto destroy_cdev;
}
/*在/dev/目录和/sys/class/hello目录下分别创建设备文件hello*/
temp = device_create(hello_class, NULL, dev, "%s", HELLO_DEVICE_FILE_NAME);
if(IS_ERR(temp)) {
err = PTR_ERR(temp);
printk(KERN_ALERT"Failed to create hello device.");
goto destroy_class;
}
/*在/sys/class/hello/hello目录下创建属性文件val*/
err = device_create_file(temp, &dev_attr_val);
if(err < 0) {
printk(KERN_ALERT"Failed to create attribute val.");
goto destroy_device;
}
dev_set_drvdata(temp, hello_dev);
#endif /* #ifdef HELLO_DEVFS_BUILD */
#ifdef HELLO_PROC_BUILD
/*创建/proc/hello文件*/
hello_create_proc();
#endif
printk(KERN_ALERT"Succedded to initialize hello device.\n");
return 0;
destroy_device:
device_destroy(hello_class, dev);
destroy_class:
class_destroy(hello_class);
destroy_cdev:
cdev_del(&(hello_dev->dev));
cleanup:
kfree(hello_dev);
unregister:
unregister_chrdev_region(MKDEV(hello_major, hello_minor), 1);
fail:
return err;
}
static int __init hello_init(void) {
int err = -1;
dev_t dev = 0;
struct device* temp = NULL;
printk(KERN_ALERT "Initializing hello device.\n");
err = alloc_chrdev_region(&dev, 0, 1, HELLO_DEVICE_NODE_NAME);
if (err < 0) {
printk(KERN_ALERT "Failed to alloc char dev region. \n");
goto fail;
}
hello_major = MAJOR(dev);
hello_minor = MINOR(dev);
hello_dev = kmalloc(sizeof(struct hello_android_dev), GFP_KERNEL);
if (!hello_dev) {
err = -ENOMEM;
printk(KERN_ALERT "Failed to alloc hello_dev.\n");
goto unregister;
}
err = __hello_setup_dev(hello_dev);
if (err) {
printk(KERN_ALERT "Failed to setup dev: %d.\n", err);
goto cleanup;
}
/* create the hello directory under directory /sys/class */
hello_class = class_create(THIS_MODULE, HELLO_DEVICE_CLASS_NAME);
if (IS_ERR(hello_class)) {
err = PTR_ERR(hello_class);
printk(KERN_ALERT "Failed to create hello class.\n");
goto destroy_cdev;
}
/* create the hello file under directory /dev/ and /sys/class/hello */
temp = device_create(hello_class, NULL, dev, NULL, "%s", HELLO_DEVICE_FILE_NAME);
if (IS_ERR(temp)) {
err = PTR_ERR(temp);
printk(KERN_ALERT "Failed to create hello device.\n");
goto destroy_class;
}
/* crate the property file val under directory /sys/class/hello/hello */
err = device_create_file(temp, &dev_attr_val);
if (err < 0) {
printk(KERN_ALERT "Failed to create attribute val.\n");
goto destroy_device;
}
dev_set_drvdata(temp, hello_dev);
hello_create_proc();
printk(KERN_ALERT "Succedded to initialize hello device.\n");
return 0;
destroy_device:
device_destroy(hello_class, dev);
destroy_class:
class_destroy(hello_class);
destroy_cdev:
cdev_del(&(hello_dev->dev));
cleanup:
kfree(hello_dev);
unregister:
unregister_chrdev_region(MKDEV(hello_major, hello_minor), 1);
fail:
return err;
}
