All of lore.kernel.org
 help / color / mirror / Atom feed
From: Greg KH <greg@kroah.com>
To: "Murali K. Vemuri" <vemuri.muralikrishna@gmail.com>
Cc: Ryan Mallon <rmallon@gmail.com>, linux-kernel@vger.kernel.org
Subject: Re: kernel panic with simple driver
Date: Tue, 9 Aug 2011 19:16:30 -0700	[thread overview]
Message-ID: <20110810021630.GA23748@kroah.com> (raw)
In-Reply-To: <CAME+iuf=mNy=s16y6LFZ7MpFWFg26UxjTF64o6smtC3=WgERkw@mail.gmail.com>

On Wed, Aug 10, 2011 at 10:33:28AM +0900, Murali K. Vemuri wrote:
> There is no concurrent access to the timer. The design is that:
> 1.Driver provides an IOCTL for start / stop
> 2. when the driver receives START IOCTL, it toggles some GPIOs to ON / OFF.
> 3. the GPIOs will be ON for 500 MSec and OFF for 500 MSec.
> 4. Two successive START IOCTLs will not be honored.
> 5. There is only one application that uses these IOCTLs
> 6. When I receive a STOP IOCTL, I am doing :
> if (timer_pending (&my_timer))
> del_timer(&my_timer);

What kind of driver is this?  For what type of hardware?

Can't you control the gpios from userspace with out any need to write a
kernel driver?

thanks,

greg k-h

  reply	other threads:[~2011-08-10  2:17 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-08-10  0:16 kernel panic with simple driver Murali K. Vemuri
2011-08-10  0:42 ` Ryan Mallon
2011-08-10  1:33   ` Murali K. Vemuri
2011-08-10  2:16     ` Greg KH [this message]
2011-08-10  2:29       ` Murali K. Vemuri
2011-08-10  2:35         ` Ryan Mallon

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20110810021630.GA23748@kroah.com \
    --to=greg@kroah.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=rmallon@gmail.com \
    --cc=vemuri.muralikrishna@gmail.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.