Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757588AbbGGONj (ORCPT ); Tue, 7 Jul 2015 10:13:39 -0400 Received: from sauhun.de ([89.238.76.85]:33658 "EHLO pokefinder.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757456AbbGGONT (ORCPT ); Tue, 7 Jul 2015 10:13:19 -0400 Date: Tue, 7 Jul 2015 16:13:12 +0200 From: Wolfram Sang To: Uwe =?utf-8?Q?Kleine-K=C3=B6nig?= Cc: Jan =?utf-8?B?TMO8YmJl?= , Grygorii Strashko , Sekhar Nori , linux-i2c@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Mike Looijmans , Kevin Hilman , Santosh Shilimkar , Murali Karicheri , devicetree@vger.kernel.org Subject: Re: [PATCH v2 5/5] i2c: davinci: use ICPFUNC to toggle I2C as gpio for bus recovery Message-ID: <20150707141312.GC3411@katana> References: <1417010393-30598-1-git-send-email-grygorii.strashko@ti.com> <1417010393-30598-6-git-send-email-grygorii.strashko@ti.com> <20141126160407.GN4431@pengutronix.de> <5476085B.40009@ti.com> <1436276269.3344.94.camel@pengutronix.de> <20150707134852.GE9671@pengutronix.de> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="nmemrqcdn5VTmUEE" Content-Disposition: inline In-Reply-To: <20150707134852.GE9671@pengutronix.de> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3606 Lines: 86 --nmemrqcdn5VTmUEE Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Jul 07, 2015 at 03:48:52PM +0200, Uwe Kleine-K=C3=B6nig wrote: > Hello, >=20 > On Tue, Jul 07, 2015 at 03:37:49PM +0200, Jan L=C3=BCbbe wrote: > > On Mi, 2014-11-26 at 19:05 +0200, Grygorii Strashko wrote: > > > On 11/26/2014 06:04 PM, Uwe Kleine-K=C3=B6nig wrote: > > > > On Wed, Nov 26, 2014 at 03:59:53PM +0200, Grygorii Strashko wrote: > > > >> Having a board where the I2C bus locks up occasionally made it cle= ar > > > >> that the bus recovery in the i2c-davinci driver will only work on > > > >> some boards, because on regular boards, this will only toggle GPIO > > > >> lines that aren't muxed to the actual pins. > > > >> > > > >> The I2C controller on SoCs like da850 (and da830), Keystone 2 has = the > > > >> built-in capability to bit-bang its lines by using the ICPFUNC reg= isters > > > >> of the i2c controller. > > > >> Implement the suggested procedure by toggling SCL and checking SDA= using > > > >> the ICPFUNC registers of the I2C controller when present. Allow pl= atforms > > > >> to indicate the presence of the ICPFUNC registers with a has_pfunc= platform > > > >> data flag and add optional DT property "ti,has-pfunc" to indicate > > > >> the same in DT. > > > > On what does it depend if this pfunc stuff works or not? Only the S= oC, > > > > or also on some board specific properties? > > >=20 > > > SoC / set of SoCs. Also, similar feature is supported by OMAP and AM3= 35x/AM437x SoCs > > > using I2C_SYSTEST register. > > >=20 > > > > Given the former using the > > > > compatible string to detect its availability would be better. (In t= his > > > > case also sorry, didn't consider this case when requesting the prop= erty > > > > in the last round.) > >=20 > > I only stumbled across this after it was merged, with the additional > I also wonder how it came to the Reviewed-by tag for me. The last thing > that I said about the patch was "On what does it depend if this pfunc > stuff works or not? Only the SoC, or also on some board specific > properties?" (see above) and "the patch looks ok". IMHO this hardly > justifies to add the Reviewed-by tag for the next round. :-( That needs to be discussed with Grygorii. I can't verify the correctness of tags for every patch, although I do try to keep an eye on it... --nmemrqcdn5VTmUEE Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBAgAGBQJVm954AAoJEBQN5MwUoCm2ltgQAJO2ysHyJhuGYg+qe7+hK2qB ZpOA7s0U9uSkVczWOBuNvdGorPsLX/L479LwfyzGYcMfqNLWOr9uj+m9V0rPzV2S JOISCDQ3rX3HNYZJW716S0c7LgL4QVCli8zbNYDioCJ7kCCM33Fsoa2TwMwD+UcX FfbBQRRw7Ou0DOJ3y3Nwo8NeUOUJv+L8N/JLs1Vz8lw13bBoRvWUtZCc3lEqsKPE TDUu2Oot2qqK6cYyAk0gi+gbikYPvj9GXWeVZRfYKz5Lr98s+gnuZSaS0/nJDwhu 6YQxZ6edwuqpuXubB1zW3VhBMc3LNSH0vvG2qWKWSfi0UnuNai/MiyPvd2OE/GPU Oux1Q0d+e3ZjL+lyz7NtCL7dm4J0SaVZcaMokT/kYjDuaGPhTzD61WMH9xqGIDYL F/6G5tjclrSU3lScl+hcmAENHRnodWaEbjML+vpoFnxOI5dQSsAAaci4ONfa4mqm teilrlSzjLczwlhd9Jvi3FqspJKH6RPCJT+E56yB404bym8VvXGWJv+uM/137acA as4n5fSdp8ydMotegIv7QirNAd6U03BKXD5hqK0Oq+c+1+JVbIfPC6xucfcrmItV CC5w/YEE2fHBpSzVvxsELUO/EPC/ZIFLCr0N9tiRHtO1DxXY0W2wtNgDLOJ9xdyV P30F6aQybrLPtXEpAIo/ =cxHH -----END PGP SIGNATURE----- --nmemrqcdn5VTmUEE-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/