From: Marc Kleine-Budde <mkl@pengutronix.de>
To: Florian Feldbauer <florian@ep1.ruhr-uni-bochum.de>,
linux-can@vger.kernel.org
Subject: Re: Writing socketCAN module for my own hardware
Date: Tue, 12 Aug 2014 10:24:07 +0200 [thread overview]
Message-ID: <53E9CF27.90400@pengutronix.de> (raw)
In-Reply-To: <53E9C774.3040401@ep1.ruhr-uni-bochum.de>
[-- Attachment #1: Type: text/plain, Size: 1444 bytes --]
On 08/12/2014 09:51 AM, Florian Feldbauer wrote:
> I have developed a CAN interface for the Raspberry Pi computer using the
> SJA1000 directly connected to the GPIOs of the CPU.
This sounds very slow :)
> So far this interface is used as chardev and works fine.
> But I'm also developing a user-space program using this CAN interface.
> This program should also be compatible with other CAN interfaces like
> the ones from PEAK or Kvazer. So I thought using socketCAN would be a
> good idea.
Yes.
> Is there any documentation on how to write a socketCAN compatible kernel
> module for my own hardware?
> I tried writing something similar to the sja1000_isa driver...
IMHO sja1000_platform.c is a better blueprint, as it uses the device
tree to describe the hardware and does not rely on module parameters.
> So far my modified kernel compiles and I can change bitrate and bring
> the interface up.
> But as soon as I try to send a CAN frame I get the error:
> Error 105: No buffer space available
You are sending CAN frames faster than the driver is able to send them,
you have to wait a bit, before sending new CAN frames.
Marc
--
Pengutronix e.K. | Marc Kleine-Budde |
Industrial Linux Solutions | Phone: +49-231-2826-924 |
Vertretung West/Dortmund | Fax: +49-5121-206917-5555 |
Amtsgericht Hildesheim, HRA 2686 | http://www.pengutronix.de |
[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 181 bytes --]
next prev parent reply other threads:[~2014-08-12 8:24 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-08-12 7:51 Writing socketCAN module for my own hardware Florian Feldbauer
2014-08-12 8:24 ` Marc Kleine-Budde [this message]
2014-08-12 8:57 ` Florian Feldbauer
2014-08-12 10:01 ` Marc Kleine-Budde
2014-10-01 7:26 ` Florian Feldbauer
2014-10-01 7:49 ` Marc Kleine-Budde
2014-10-01 12:32 ` Florian Feldbauer
2014-10-01 12:41 ` Marc Kleine-Budde
2014-10-01 12:56 ` Florian Feldbauer
2014-10-01 13:11 ` Marc Kleine-Budde
2014-10-09 15:06 ` Florian Feldbauer
2014-10-09 16:13 ` Marc Kleine-Budde
2014-10-10 7:43 ` Florian Feldbauer
2014-10-10 8:06 ` Marc Kleine-Budde
2014-10-10 8:09 ` Florian Feldbauer
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=53E9CF27.90400@pengutronix.de \
--to=mkl@pengutronix.de \
--cc=florian@ep1.ruhr-uni-bochum.de \
--cc=linux-can@vger.kernel.org \
/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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).