From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759396AbcAULMT (ORCPT ); Thu, 21 Jan 2016 06:12:19 -0500 Received: from mezzanine.sirena.org.uk ([106.187.55.193]:37373 "EHLO mezzanine.sirena.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759234AbcAULMR (ORCPT ); Thu, 21 Jan 2016 06:12:17 -0500 Date: Thu, 21 Jan 2016 11:11:15 +0000 From: Mark Brown To: Lothar =?iso-8859-1?Q?Wa=DFmann?= Cc: =?iso-8859-1?Q?Beno=EEt?= Cousson , Ian Campbell , Kumar Gala , Liam Girdwood , Mark Rutland , Pawel Moll , Rob Herring , Russell King , Tony Lindgren , devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-omap@vger.kernel.org Message-ID: <20160121111115.GJ6588@sirena.org.uk> References: <1453292992-1788-1-git-send-email-LW@KARO-electronics.de> <1453292992-1788-2-git-send-email-LW@KARO-electronics.de> <20160120164258.GF6588@sirena.org.uk> <20160121080524.27af489f@ipc1.ka-ro> <20160121102015.GI6588@sirena.org.uk> <20160121112611.34e17cb2@ipc1.ka-ro> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="qb+6gLdVH5itmOEb" Content-Disposition: inline In-Reply-To: <20160121112611.34e17cb2@ipc1.ka-ro> X-Cookie: APL hackers do it in the quad. User-Agent: Mutt/1.5.24 (2015-08-30) X-SA-Exim-Connect-IP: 2a01:348:6:8808:fab::3 X-SA-Exim-Mail-From: broonie@sirena.org.uk Subject: Re: [PATCH 1/2] regulator: ltc3589: make IRQ optional X-SA-Exim-Version: 4.2.1 (built Mon, 26 Dec 2011 16:24:06 +0000) X-SA-Exim-Scanned: Yes (on mezzanine.sirena.org.uk) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --qb+6gLdVH5itmOEb Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, Jan 21, 2016 at 11:26:11AM +0100, Lothar Wa=DFmann wrote: > > On Thu, Jan 21, 2016 at 08:05:24AM +0100, Lothar Wa=DFmann wrote: > > > > On Wed, Jan 20, 2016 at 01:29:51PM +0100, Lothar Wa=DFmann wrote: > > > > > This pin is used as IRQ pin for the LTC3589 PMIC on the Ka-Ro > > > > > electronics TX48 module. Make the IRQ optional in the driver and = use a > > > > > polling routine instead if no IRQ is specified in DT. > > > > > Otherwise the driver will continuously generate interrupts and ma= ke > > > > > the system unusable. > > > > How will the driver generate interrupts if there is no interrupt > > > > physically present in the system? > > > It's using timer interrupts to poll the LTC3589 state. > > I know that is what your patch does, my question is why you say in your > > commit log that "Otherwise the driver will continuously generate > > interrupts and make the system unusable". > Because the interrupt is level triggered and the polarity of the > EXTINT pin is inverted, the interrupt will be constantly active when > the IRQ pin of the LTC3589 is inactive. So, to repeat my original question, how will that generate interrupts if there is no interrupt physically present in the system? --qb+6gLdVH5itmOEb Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQEcBAEBCAAGBQJWoLzSAAoJECTWi3JdVIfQJWUH/0kdI/s2MwYDzQXwZm+kxQ1u WeDpAM6O7jupQgg050TXcVq7aP4+0zl4tNEZT7/jB+eUDf3Xt6tNPgcIKcml7TyV q3HXshTUGhTtg8qw6WzfFAv3f3QZNR0EX2RUQ8LcTGusJWalfBQHlpw/7dZr/ykY jG8hanmJZMkuyVBnCJeqqu3zzwdQF09zRLyXdx5mahS2fisEx9zqcf2WCO3qt9su jgTakmLvzVTdCcmdE6QxWIaR5tcTGtdWYu8xwuLrDUS8/I4BMJsj9/LHdhuHd8uN ZgX36s8SEXA01yBDcBwG0rc33lsDBhlkXx88VW2SfM+KdU3laxfsdcqe+Rtvl8c= =kI6C -----END PGP SIGNATURE----- --qb+6gLdVH5itmOEb--