Re: [RFC PATCH] can: m_can: Add driver for M_CAN hardware in NVIDIA devices - Marc Kleine-Budde

From: Marc Kleine-Budde <mkl@pengutronix.de>
To: Thierry Reding <thierry.reding@gmail.com>
Cc: Brian Silverman <bsilver16384@gmail.com>,
	Brian Silverman <brian.silverman@bluerivertech.com>,
	Wolfgang Grandegger <wg@grandegger.com>,
	"David S. Miller" <davem@davemloft.net>,
	Jakub Kicinski <kuba@kernel.org>,
	Jonathan Hunter <jonathanh@nvidia.com>,
	Philipp Zabel <p.zabel@pengutronix.de>,
	Dan Murphy <dmurphy@ti.com>,
	open list <linux-kernel@vger.kernel.org>,
	"open list:CAN NETWORK DRIVERS" <linux-can@vger.kernel.org>,
	"open list:NETWORKING DRIVERS" <netdev@vger.kernel.org>,
	"open list:TEGRA ARCHITECTURE SUPPORT"
	<linux-tegra@vger.kernel.org>
Subject: Re: [RFC PATCH] can: m_can: Add driver for M_CAN hardware in NVIDIA devices
Date: Thu, 7 Apr 2022 15:01:18 +0200	[thread overview]
Message-ID: <20220407130118.hp5szzhg4v6szmbq@pengutronix.de> (raw)
In-Reply-To: <Yk2vOj8wKi4FdPg2@orome>

[-- Attachment #1: Type: text/plain, Size: 2258 bytes --]

On 06.04.2022 17:18:18, Thierry Reding wrote:
> On Wed, Jan 05, 2022 at 04:25:09PM -0800, Brian Silverman wrote:
> > It's a M_TTCAN with some NVIDIA-specific glue logic and clocks. The
> > existing m_can driver works with it after handling the glue logic.
> > 
> > The code is a combination of pieces from m_can_platform and NVIDIA's
> > driver [1].
> > 
> > [1] https://github.com/hartkopp/nvidia-t18x-can/blob/master/r32.2.1/nvidia/drivers/net/can/mttcan/hal/m_ttcan.c
> > 
> > Signed-off-by: Brian Silverman <brian.silverman@bluerivertech.com>
> > ---
> > I ran into bugs with the error handling in NVIDIA's m_ttcan driver, so I
> > switched to m_can which has been much better. I'm looking for feedback
> > on whether I should ensure rebasing hasn't broken anything, write up DT
> > documentation, and submit this patch for real. The driver works great,
> > but I've got some questions about submitting it.
> > 
> > question: This has liberal copying of GPL code from NVIDIA's
> > non-upstreamed m_ttcan driver. Is that OK?
> > 
> > corollary: I don't know what any of this glue logic does. I do know the
> > device doesn't work without it. I can't find any documentation of what
> > these addresses do.
> > 
> > question: There is some duplication between this and m_can_platform. It
> > doesn't seem too bad to me, but is this the preferred way to do it or is
> > there another alternative?
> > 
> > question: Do new DT bindings need to be in the YAML format, or is the
> > .txt one OK?
> > 
> >  drivers/net/can/m_can/Kconfig       |  10 +
> >  drivers/net/can/m_can/Makefile      |   1 +
> >  drivers/net/can/m_can/m_can_tegra.c | 362 ++++++++++++++++++++++++++++
> >  3 files changed, 373 insertions(+)
> >  create mode 100644 drivers/net/can/m_can/m_can_tegra.c
> 
> Sorry for the late reply, I completely missed this.

Brian Silverman left the company bluerivertech, I think there'll be no
progress on the tegra glue code. :/

Marc

-- 
Pengutronix e.K.                 | Marc Kleine-Budde           |
Embedded Linux                   | https://www.pengutronix.de  |
Vertretung West/Dortmund         | Phone: +49-231-2826-924     |
Amtsgericht Hildesheim, HRA 2686 | Fax:   +49-5121-206917-5555 |

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 488 bytes --]