????????????????????????????????????掳???????????????????????????????????????????????????????????????????????????C?????????????????????????????????????????????hold?????????????些?????????????????芯??????????
???????????????婕�??linux???????????????????????????????????????????led???????????????linux???????arm?????????????????????????????????????榈�??????????????????????????? ?????????泻???璞�???????????????????
????led????????????????????????????????????????????????????????鈥�??????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????效????
???????????????????led????????写??
???????????linux?????璞�?????????????????????????????????????????????锟�???linux??????????????????????linux??????????????????linux????娣�??linux???璞�?????????????????璞�/???璞�/?????璞�?????????????璞�????????????????????????????璞�?????????????????????????led???????璞�?榈�?????璞�?????????????????????????????????????????璞�???????????????璞�????姹�??????校?????????????! ?????????????????璞�???????????璞�?????????????????
?????????led????????????????????璞�?????????????????????????????????懈?????????伞???????????
????stop???????YY??????????璞�????????????????????????????????????????include?锟�??????????miscdivice.h??
????1 struct miscdevice  {
????2         int minor;
????3         const char *name;
????4         const struct file_operations *fops;
????5         struct list_head list;
????6         struct device *parent;
????7         struct device *this_device;
????8         const char *nodename;
????9         mode_t mode;
????10 };
?????e???????????娣�????????璀�???????????????????????????????????????璞�????澹�???????????????械???????????????????? f u c k
??????????????????????椋�?????????????????minor????????????????????????璞�??????????????????璞�????????璞�??????霉??????璞�??????????璞�???????????????????璞�????????????minor?????????写????????????????????????????????????????
?????????????????????????linux?????蟹??????????????????????????????? ???围?????file_operations????????????????????芯??????file_operatios??????濉�
????file_operations?????????????linux?薪??????璞�????????????????????????????????????????????????????????????????????????????????????????????read/write??????????????????????????????胁??????????wow???????????????????????????????奴??????????????????????????????????????????????????????????????????????????????????械??位???????linux???????械??位???????????????????????????????????????貌?????芯???linux??????????????????????
????????file_operations??????????????????? ???????????????奴????????????写????????so??let‘s go??
??????????????include/linux/fs.h??????????????澹�

 

1 struct file_operations {
2         struct module *owner;
3         loff_t (*llseek) (struct file *?? loff_t?? int);
4         ssize_t (*read) (struct file *?? char __user *?? size_t?? loff_t *);
5         ssize_t (*write) (struct file *?? const char __user *?? size_t?? loff_t *);
6         ssize_t (*aio_read) (struct kiocb *?? const struct iovec *?? unsigned long?? loff_t);
7         ssize_t (*aio_write) (struct kiocb *?? const struct iovec *?? unsigned long?? loff_t);
8         int (*readdir) (struct file *?? void *?? filldir_t);
9         unsigned int (*poll) (struct file *?? struct poll_table_struct *);
10         int (*ioctl) (struct inode *?? struct file *?? unsigned int?? unsigned long);
11         long (*unlocked_ioctl) (struct file *?? unsigned int?? unsigned long);
12         long (*compat_ioctl) (struct file *?? unsigned int?? unsigned long);
13         int (*mmap) (struct file *?? struct vm_area_struct *);
14         int (*open) (struct inode *?? struct file *);
15         int (*flush) (struct file *?? fl_owner_t id);
16         int (*release) (struct inode *?? struct file *);
17         int (*fsync) (struct file *?? struct dentry *?? int datasync);
18         int (*aio_fsync) (struct kiocb *?? int datasync);
19         int (*fasync) (int?? struct file *?? int);
20         int (*lock) (struct file *?? int?? struct file_lock *);
21         ssize_t (*sendpage) (struct file *?? struct page *?? int?? size_t?? loff_t *?? int);
22         unsigned long (*get_unmapped_area)(struct file *?? unsigned long?? unsigned long?? unsigned long?? unsigned long);
23          int (*check_flags)(int);
24         int (*flock) (struct file *?? int?? struct file_lock *);
25         ssize_t (*splice_write)(struct pipe_inode_info *?? struct file *?? loff_t *?? size_t?? unsigned int);
26         ssize_t (*splice_read)(struct file *?? loff_t *?? struct pipe_inode_info *?? size_t?? unsigned int);
27         int (*setlease)(struct file *?? long?? struct file_lock **);
28 };

????????????????????????????????????????????????????????????????????????????????????????????????????????????芯????????ower??ioctl????????????ower????????????????????椋�??ioctl?????????