Problems with adding a sysfs file

[Tobin C. Harding]

On Mon, Apr 17, 2017 at 02:04:48PM -0700, Abhishek Bhardwaj wrote:
> I used a pr_debug and printk KERN_INFO ,before my original email , to
> verify they weren't being called.

You will have more success on kernel mailing lists if you do not top
post as you have done :)

> On Apr 17, 2017 1:43 PM, <valdis.kletnieks at vt.edu> wrote:
> 
> > On Mon, 17 Apr 2017 01:17:08 -0700, Abhishek Bhardwaj said:
> > > I followed this link to add a sysfs file
> > > http://kroah.com/log/blog/2013/06/26/how-to-create-a-
> > sysfs-file-correctly/
> > > .
> > >
> > > I set the driver.groups field and declared the attribute and attribute
> > > groups required by the sysfs file. When I boot my kernel I see the
> > > file but my store and show handlers don't get called when I try to cat
> > > or echo to the file. Is there any step I'm missing ?.
> >
> > The traditional way to start debugging this is to add a line at the
> > beginning
> > of your show and store routines:
> >
> >         printk(KERN_DEBUG "Now in our special sysfs show routine\n");

You could have put your response here, that way readers would have a
reference to you comment.

> > and see if it shows up in your dmesg or not.  If not, your routine
> > is probably not being called.  If it is, the problem is in the routine.
> >
> > (You'd be surprised how often people say their routine isn't getting
> > called,
> > when it in fact is, or vice versa..)
> >

Good luck,
Tobin.