From: Marc Kleine-Budde Subject: Re: [PATCH] socketcan: add a driver for FlexCAN controllers. Date: Fri, 18 Jun 2010 13:21:32 +0200 Message-ID: <4C1B56BC.1050303@pengutronix.de> References: <20100617105201.GA2015@bluebox.local> <4C1B4098.3090800@grandegger.com> <4C1B4796.3060506@pengutronix.de> <4C1B4B85.3010905@grandegger.com> <4C1B4DF0.2090103@pengutronix.de> <4C1B52A7.3060607@grandegger.com> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============5697370433625418308==" Cc: socketcan-core-0fE9KPoRgkgATYTw5x5z8w@public.gmane.org, netdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Wolfgang Grandegger Return-path: In-Reply-To: <4C1B52A7.3060607-5Yr1BZd7O62+XT7JhA+gdA@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: socketcan-core-bounces-0fE9KPoRgkgATYTw5x5z8w@public.gmane.org Errors-To: socketcan-core-bounces-0fE9KPoRgkgATYTw5x5z8w@public.gmane.org List-Id: netdev.vger.kernel.org This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --===============5697370433625418308== Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enigAFDCFDFE6A0A21398054C256" This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enigAFDCFDFE6A0A21398054C256 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Wolfgang Grandegger wrote: > On 06/18/2010 12:44 PM, Marc Kleine-Budde wrote: >> Wolfgang Grandegger wrote: >>> On 06/18/2010 12:16 PM, Marc Kleine-Budde wrote: >>>> Wolfgang Grandegger wrote: >>>>> Hi Hans-J=FCrgen, >>>>> >>>>> On 06/17/2010 12:52 PM, Hans J. Koch wrote: >>>>>> This adds a driver for FlexCAN based CAN controllers, >>>>>> e.g. found in Freescale i.MX35 SoCs. >>>>>> >>>>>> The original version of this driver was posted by Sascha Hauer in = July 2009: >>>>>> http://kerneltrap.org/mailarchive/linux-netdev/2009/7/29/6251621 >>>>>> >>>>>> I took this version, added NAPI support, and fixed some problems f= ound >>>>>> during testing. Well, here is the result. Please review. >>>>> I briefly browsed the patch and various bits and pieces are missing= or >>>>> not correctly implemented. Marc already pointed out a few of them: >>>>> >>>>> - I do not find can_put/get_echo_skb functions in the code. How is >>>>> IFF_ECHO supposed to work? >>>> the driver uses hardware loopback >>> OK, then >>> >>> dev =3D alloc_candev(sizeof(struct flexcan_priv), 0); >>> >>> should be used (and TX_ECHO_SKB_MAX removed) in Hans-J=FCrgens driver= =2E >>> >>>>> - Support for CAN_CTRLMODE_BERR_REPORTING and do_get_berr_counter()= >>>>> seems to be missing. >>>>> >>>>> - Make use of alloc_can_skb() and alloc_can_err_skb(). >>>> the last two points are already addressed in my version of the drive= r. >>> I do not see support for CAN_CTRLMODE_BERR_REPORTING in your driver >>> (which has nothing to do with do_get_berr_counter). >> oh yes...sorry, got confused. >> >> However I implemented CAN_CTRLMODE_BERR_REPORTING, i.e. turning of the= >> bit error interrupts by default. This has the effect that no bus warni= ng >> and bus passive interrupt was signalled. >> >> I should add a comment to my driver. >=20 > I'm confused, CAN_CTRLMODE_BERR_REPORTING means that the user can enabl= e > bus error reporting, which seems not be handled in the driver your sent= =2E > See: >=20 > http://lxr.linux.no/linux/drivers/net/can/sja1000/sja1000.c#L134 > http://lxr.linux.no/linux/drivers/net/can/sja1000/sja1000.c#L588 Which interrupts does "IRQ_BEI" include? What should CAN_CTRLMODE_BERR_REPORTING do? Looking at: http://lxr.linux.no/linux+v2.6.34/drivers/net/can/sja1000/sja1000.c#L393 it seems that BEI on the SJA just effects bit, form and stuff errors. If I disable the corresponding interrupt in the flexcan. This is ERR_MSK, (1 << 14 in CTRL), I don't get error warning or error passive interrupts either. I'm not sure about the bus off interrupt. =46rom my point of view this is not that what CAN_CTRLMODE_BERR_REPORTING= should do, is it? Marc --=20 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 | --------------enigAFDCFDFE6A0A21398054C256 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iEYEARECAAYFAkwbVsEACgkQjTAFq1RaXHP8eACfRlSXd74vbPAruTkJiFqncyO6 daUAoJLainmilniEgJuxWa7Rk/cYc3lq =ONIm -----END PGP SIGNATURE----- --------------enigAFDCFDFE6A0A21398054C256-- --===============5697370433625418308== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Socketcan-core mailing list Socketcan-core-0fE9KPoRgkgATYTw5x5z8w@public.gmane.org https://lists.berlios.de/mailman/listinfo/socketcan-core --===============5697370433625418308==--