Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030763Ab3DSOoo (ORCPT ); Fri, 19 Apr 2013 10:44:44 -0400 Received: from mga11.intel.com ([192.55.52.93]:12085 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030615Ab3DSOon convert rfc822-to-8bit (ORCPT ); Fri, 19 Apr 2013 10:44:43 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.87,509,1363158000"; d="scan'208";a="321733789" Message-ID: <1366382678.7932.104.camel@smile> Subject: Re: [PATCH] platform: fall-back to driver name check if there is no id found From: Andy Shevchenko To: Eric Miao Cc: Hein Tibosch , Mika Westerberg , Greg KH , Linux Kernel Mailing List Date: Fri, 19 Apr 2013 17:44:38 +0300 In-Reply-To: References: <51713A25.308@yahoo.es> Organization: Intel Finland Oy Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT X-Mailer: Evolution 3.4.4-3 Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2930 Lines: 68 On Fri, 2013-04-19 at 21:20 +0800, Eric Miao wrote: > On Fri, Apr 19, 2013 at 8:35 PM, Hein Tibosch wrote: > > Hi Andy, Mika, > > > > On 8 Feb 2013, Andy Shevchenko wrote: > > > >> Some of the platform devices rely on the name of their driver to match with. In > >> the current implementation, if platform id table is needed, they have to add > >> the name to the platform id table which sounds alogical. The patch adjustes the > >> logic of the id table matching to make sure we will fall-back to match by the > >> driver name. This will make it similar to the DT or ACPI cases. > >> > >> Signed-off-by: Andy Shevchenko > >> Reported-by: Mika Westerberg > >> Cc: Eric Miao > >> Cc: Greg Kroah-Hartman > >> --- > >> drivers/base/platform.c | 4 ++-- > >> 1 file changed, 2 insertions(+), 2 deletions(-) > >> > >> diff --git a/drivers/base/platform.c b/drivers/base/platform.c > >> index c0b8df3..452ba4b 100644 > >> --- a/drivers/base/platform.c > >> +++ b/drivers/base/platform.c > >> @@ -732,8 +732,8 @@ static int platform_match(struct device *dev, struct device_driver *drv) > >> return 1; > >> > >> /* Then try to match against the id table */ > >> - if (pdrv->id_table) > >> - return platform_match_id(pdrv->id_table, pdev) != NULL; > >> + if (pdrv->id_table && platform_match_id(pdrv->id_table, pdev)) > >> + return 1; > >> > >> /* fall-back to driver name match */ > >> return (strcmp(pdev->name, drv->name) == 0); > > > > When I upgraded an avr32 system from 3.8 to a recent next release, I found it was > > broken: DMA was not available because the dw_dma driver did not get probed anymore. > > > > The dw_dma driver does have a id_table, but the boards in arch/avr32 are still expecting > > driver identification by name. > > I think this is a different philosophy here. I'm actually fine with either. The > questions are really: > > 1. will it be a bit inconsistent if the driver is using id_table, > while the device > is still using a legacy way? Legacy way may be considered as a fall-back. > 2. instead of introducing a different logic in the platform driver core code, > is it possible this could be fixed at the board level? It might be fixed in the driver, though I think that is ugly approach, by adding name of the driver into its id_table. P.S. There are actually a few drivers in current mainline that uses mentioned approach, but with this patch it will be not needed anymore. -- Andy Shevchenko Intel Finland Oy -- 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/