From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752603AbbEHKe7 (ORCPT ); Fri, 8 May 2015 06:34:59 -0400 Received: from opensource.wolfsonmicro.com ([80.75.67.52]:54610 "EHLO opensource.wolfsonmicro.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751071AbbEHKe4 (ORCPT ); Fri, 8 May 2015 06:34:56 -0400 Date: Fri, 8 May 2015 11:34:54 +0100 From: Nariman Poushin To: Mark Brown Cc: linux-kernel@vger.kernel.org, patches@opensource.wolfsonmicro.com Subject: Re: [RFC][PATCH] regmap: make REGCACHE_NONE maps return error on regcache_sync Message-ID: <20150508103454.GA13160@opensource.wolfsonmicro.com> References: <20150508095537.GA15394@opensource.wolfsonmicro.com> <20150508102019.GX22845@sirena.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150508102019.GX22845@sirena.org.uk> User-Agent: Mutt/1.5.17+20080114 (2008-01-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, May 08, 2015 at 11:20:19AM +0100, Mark Brown wrote: > On Fri, May 08, 2015 at 10:55:37AM +0100, Nariman Poushin wrote: > > Signed-off-by: Nariman Poushin > > --- > > regcache currently causes a BUG_ON if cache_sync/sync_region is > > called on a map with cache_type REGCACHE_NONE. This is not > > consistent with the behaviour of regcache_read/write which > > currently just return -ENOSYS and only throws a BUG_ON if > > the cache_type is something that _should_ have cache ops, > > but doesn't. Sure your device might not work, it but doesn't > > seem right to panic the kernel. The other option I suppose > > is to change it to a WARN_ON. > > Please submit patches in the format covered in SubmittingPatches, the > changelog goes before the signoff. > Will do, apologies. > The reason this is so loud is that while it's reasonable that generic > code could end up triggering a write it's difficult to see any way in > which a sync could be triggered on a device without a cache without it > being an obvious bug. Since people frequently don't bother checking > return codes loud log messages are our only real way of reporting this, > given where syncs tend to happen it's not likely to happen in an obscure > code path that won't get seen. Fair enough, that makes sense. Thanks Nariman