Thanks, i remember that in the 3rd chapter of the Rubini'sbook
there explain something like you wrote to me.
Now I have understead to steps to do.
Thanks
Claudio Fiorini
Scrive Shine Mohamed Jabbar <shinemohamed_j@naturesoft.net>:
> On Tue, 2004-04-27 at 10:07, Claudio Fiorini wrote:
> > Hi,
> > I'm new to kernel hacking, I'm trying to devel a kernel module to use
> > parallel port with simple led because i do in user-space, but now
> > i want to do that in kernel-space.
> > I start to read the linux device driver 2nd edition and I'm
> > ok where i register a char device, but the book show
> > me the file_operations struct that has many pointers functions
> > this is what i do:
> >
> > struct file_operations *f_pport;
>
> In my opinion, u need to define file operations and
> then pass it over to the register_chrdev.
>
> Eg:
> struct file_operations f_pport {
>
> .owner = THIS_MODULE,
> .open = Your_open_function, /* U may refer any of the
> * character device code
> */
> .write = Your_write_function, /* Function pointer to do your
> * function, LED write
> */
> .read = Your_read_function, /* Function pointer to do your
> * function, LED read
> */
> ...
> }
>
>
> > pport = register_chrdev(PPORT_MAJOR_NUMBER, PPORT_CONST_NAME,
> > f_pport);
>
>
> Here u are registering a char device using
> the major number PPORT_MAJOR_NUMBER. Using this major number
> u can make a character device with a minor number from
> the userland. This can be done using command mknod.
>
> >
> > now if i want to open i have to do something like this?
> > f_pport->open(struct inode *, struct file *);
>
> I think u don't need to call the open function from the
> kernel module. When u try to open the character device
> file from userland after registration, it will be called
> ( kernel will do it ).
>
> Similarly, when u write to the device file your write function
> will be called. ( echo something > /dev/your_device )
>
> >
> > and in the book i don't understand which information i have
> > to give to struct inode and struct file.
> >
> > Thanks
> >
> > Claudio
>
> Regards,
> Shine Mohamed Jabbar
>
>
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