From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751997AbbDNFKc (ORCPT ); Tue, 14 Apr 2015 01:10:32 -0400 Received: from mail-wi0-f174.google.com ([209.85.212.174]:37186 "EHLO mail-wi0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751020AbbDNFKZ (ORCPT ); Tue, 14 Apr 2015 01:10:25 -0400 Message-ID: <552CA12F.30800@monstr.eu> Date: Tue, 14 Apr 2015 07:10:07 +0200 From: Michal Simek Reply-To: monstr@monstr.eu User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.6.0 MIME-Version: 1.0 To: Greg Kroah-Hartman , Michal Simek CC: linux-kernel@vger.kernel.org, Arnd Bergmann , stable@vger.kernel.org, linux-serial@vger.kernel.org, Jiri Slaby Subject: Re: [PATCH] serial: of-serial: Remove device_type = "serial" registration References: <20150413170044.GD32634@kroah.com> In-Reply-To: <20150413170044.GD32634@kroah.com> Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="P160ICejguaOlKl5Vsm6kivXSAGAmljHM" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --P160ICejguaOlKl5Vsm6kivXSAGAmljHM Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: quoted-printable Hi Greg, On 04/13/2015 07:00 PM, Greg Kroah-Hartman wrote: > On Mon, Apr 13, 2015 at 04:35:27PM +0200, Michal Simek wrote: >> Do not probe all serial drivers by of_serial.c which are using >> device_type =3D "serial"; property. Only drivers which have valid >> compatible strings listed in the driver should be probed. >=20 > Why? This was added for some reason, what has changed since then? I was discussing this patch with Arnd over IRC. This is what Arnd was saying yesterday. "when I wrote that driver initially, the idea was that it would get used as a stub to hook up all other serial drivers but after that, the common code learned to create platform devices from D= T" and resolution from our discussion was to remove this line because make no sense to probe all drivers which has device_type =3D "serial". It was causing the problem on one system with xilinx_uartps and 16550a IP where of_serial failed to register for xilinx_uartps and because of irq_dispose_mapping removed irq_desc. Then when xilinx_uartps was asking for irq with request_irq() it was returning EINVAL. The first problem was that of_serial tried to bind driver because of device_type =3D "serial"; and the second problem was in xilinx_uartps driver by incorrectly using platform_get_resources() which doesn't create irq mapping which is fixed by the second patch. Thanks, Michal --=20 Michal Simek, Ing. (M.Eng), OpenPGP -> KeyID: FE3D1F91 w: www.monstr.eu p: +42-0-721842854 Maintainer of Linux kernel - Microblaze cpu - http://www.monstr.eu/fdt/ Maintainer of Linux kernel - Xilinx Zynq ARM architecture Microblaze U-BOOT custodian and responsible for u-boot arm zynq platform --P160ICejguaOlKl5Vsm6kivXSAGAmljHM Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.14 (GNU/Linux) iEYEARECAAYFAlUsoT0ACgkQykllyylKDCFVLACeKj3XY5p2iz3vWXs8nP0pATNc wJwAoIMt+VSD1iWagIFIzakCQMBBFUr+ =OCGj -----END PGP SIGNATURE----- --P160ICejguaOlKl5Vsm6kivXSAGAmljHM--