[Linux-parport] Re: [RFC]: add sysfs support to parport_pc, v3

Jason Dravet dravet at hotmail.com
Tue Jan 3 22:24:39 EST 2006

>From: Greg KH <greg at kroah.com>
> > +++ /usr/src/linux-2.6.14/drivers/parport/parport_pc.c	2006-01-01
> > 11:29:05.000000000 -0600
>Line wrapped so it can't be applied :(
> > + * Added sysfs and udev - Jason Dravet <dravet at hotmail.com>
> >  */
>Doesn't belong here, this goes in the change log.
My mistake.

> > +#include <linux/sysfs.h>
>Your email client also ate the leading spaces :(
My email client is hotmail.  I have come to realize how much hotmail sucks 
for email.  It eats the leading spaces, converts tabs to spaces, and line 
wraps.  I will work on getting a new mail account.

> > +	class_device_create(parallel_class, NULL, MKDEV(6, countports),
> > NULL, "lp%i", countports);
> > +	class_device_create(parallel_class, NULL, MKDEV(99, countports),
> > NULL, "parport%i", countports);
> > +	countports++;
>What does the 6 and 99 come from?  Aren't these #defined in a header file 
Good question.  The answer is I have no idea.  I booted Fedora Core and I 
did a ls -l /dev and wrote down the specs for lp0 and parport0.  lp0 looked 
like crw-rw----  root   lp   6,  0  date  lp0 so that is what I used.  After 
reading Linux Device Drivers I found out that 6 is the major number and 0 is 
the minor number.  The goal was to make sure that the nodes generated by my 
patch were the same as the nodes generated before my patch so I used those 
numbers.  Should I have used different major numbers?


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