From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pankaj Dubey Subject: RE: [PATCH v2] mfd: syscon: Decouple syscon interface from platform devices Date: Thu, 04 Sep 2014 10:15:27 +0530 Message-ID: <002701cfc7fb$110a7350$331f59f0$@samsung.com> References: <1409668935-10667-1-git-send-email-pankaj.dubey@samsung.com> <6034841.GFrG3XCMdb@wuerfel> <20140903151611.260a7218@bbrezillon> <4224773.hl3QDeILqz@wuerfel> <20140903161528.05f566e1@bbrezillon> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Return-path: Received: from mailout2.samsung.com ([203.254.224.25]:55344 "EHLO mailout2.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750908AbaIDEnT (ORCPT ); Thu, 4 Sep 2014 00:43:19 -0400 In-reply-to: <20140903161528.05f566e1@bbrezillon> Content-language: en-us Sender: linux-samsung-soc-owner@vger.kernel.org List-Id: linux-samsung-soc@vger.kernel.org To: 'Boris BREZILLON' , 'Arnd Bergmann' Cc: kgene.kim@samsung.com, linux@arm.linux.org.uk, 'Alexander Shiyan' , naushad@samsung.com, 'Tomasz Figa' , linux-kernel@vger.kernel.org, joshi@samsung.com, linux-samsung-soc@vger.kernel.org, thomas.ab@samsung.com, tomasz.figa@gmail.com, vikas.sajjan@samsung.com, chow.kim@samsung.com, lee.jones@linaro.org, 'Michal Simek' , linux-arm-kernel@lists.infradead.org, 'Mark Brown' Hi Boris, On Wednesday, September 03, 2014 Boris BREZILLON wrote, > To: Arnd Bergmann > Cc: Pankaj Dubey; kgene.kim@samsung.com; linux@arm.linux.org.uk; Alexander > Shiyan; naushad@samsung.com; Tomasz Figa; linux-kernel@vger.kernel.org; > joshi@samsung.com; linux-samsung-soc@vger.kernel.org; thomas.ab@samsung.com; > tomasz.figa@gmail.com; vikas.sajjan@samsung.com; chow.kim@samsung.com; > lee.jones@linaro.org; Michal Simek; linux-arm-kernel@lists.infradead.org; Mark > Brown > Subject: Re: [PATCH v2] mfd: syscon: Decouple syscon interface from platform > devices > > On Wed, 03 Sep 2014 15:49:04 +0200 > Arnd Bergmann wrote: > > > On Wednesday 03 September 2014 15:16:11 Boris BREZILLON wrote: > > > I checked that part, and it appears most of the code is already > > > there (see usage of regmap_attach_dev function here [1]). > > > > > > The only problem I see is that errors are still printed with > > > dev_err, which, AFAIK, will trigger a kernel panic if dev is NULL. > > > > Actually not: > > > > static int __dev_printk(const char *level, const struct device *dev, > > struct va_format *vaf) { > > if (!dev) > > return printk("%s(NULL device *): %pV", level, vaf); > > > > return dev_printk_emit(level[1] - '0', dev, > > "%s %s: %pV", > > dev_driver_string(dev), dev_name(dev), > > vaf); } > > > > My bad then (I don't know where I looked at to think NULL dev was not gracefully > handled :-)). Thanks for pointing this out. > Given that, I think it should work fine even with a NULL dev. > I'll give it a try on at91 ;-). > We have tested this patch, on Exynos board and found working well. In our use case DT based drivers such as USB Phy, SATA Phy, Watchdog are calling syscon_regmap_lookup_by APIs to get regmap handle to Exynos PMU and it worked well for these drivers. It would be great if after testing you share result here or give a Tested-By. Thanks, Pankaj Dubey > Best Regards, > > Boris > > -- > Boris Brezillon, Free Electrons > Embedded Linux and Kernel engineering > http://free-electrons.com From mboxrd@z Thu Jan 1 00:00:00 1970 From: pankaj.dubey@samsung.com (Pankaj Dubey) Date: Thu, 04 Sep 2014 10:15:27 +0530 Subject: [PATCH v2] mfd: syscon: Decouple syscon interface from platform devices In-Reply-To: <20140903161528.05f566e1@bbrezillon> References: <1409668935-10667-1-git-send-email-pankaj.dubey@samsung.com> <6034841.GFrG3XCMdb@wuerfel> <20140903151611.260a7218@bbrezillon> <4224773.hl3QDeILqz@wuerfel> <20140903161528.05f566e1@bbrezillon> Message-ID: <002701cfc7fb$110a7350$331f59f0$@samsung.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi Boris, On Wednesday, September 03, 2014 Boris BREZILLON wrote, > To: Arnd Bergmann > Cc: Pankaj Dubey; kgene.kim at samsung.com; linux at arm.linux.org.uk; Alexander > Shiyan; naushad at samsung.com; Tomasz Figa; linux-kernel at vger.kernel.org; > joshi at samsung.com; linux-samsung-soc at vger.kernel.org; thomas.ab at samsung.com; > tomasz.figa at gmail.com; vikas.sajjan at samsung.com; chow.kim at samsung.com; > lee.jones at linaro.org; Michal Simek; linux-arm-kernel at lists.infradead.org; Mark > Brown > Subject: Re: [PATCH v2] mfd: syscon: Decouple syscon interface from platform > devices > > On Wed, 03 Sep 2014 15:49:04 +0200 > Arnd Bergmann wrote: > > > On Wednesday 03 September 2014 15:16:11 Boris BREZILLON wrote: > > > I checked that part, and it appears most of the code is already > > > there (see usage of regmap_attach_dev function here [1]). > > > > > > The only problem I see is that errors are still printed with > > > dev_err, which, AFAIK, will trigger a kernel panic if dev is NULL. > > > > Actually not: > > > > static int __dev_printk(const char *level, const struct device *dev, > > struct va_format *vaf) { > > if (!dev) > > return printk("%s(NULL device *): %pV", level, vaf); > > > > return dev_printk_emit(level[1] - '0', dev, > > "%s %s: %pV", > > dev_driver_string(dev), dev_name(dev), > > vaf); } > > > > My bad then (I don't know where I looked at to think NULL dev was not gracefully > handled :-)). Thanks for pointing this out. > Given that, I think it should work fine even with a NULL dev. > I'll give it a try on at91 ;-). > We have tested this patch, on Exynos board and found working well. In our use case DT based drivers such as USB Phy, SATA Phy, Watchdog are calling syscon_regmap_lookup_by APIs to get regmap handle to Exynos PMU and it worked well for these drivers. It would be great if after testing you share result here or give a Tested-By. Thanks, Pankaj Dubey > Best Regards, > > Boris > > -- > Boris Brezillon, Free Electrons > Embedded Linux and Kernel engineering > http://free-electrons.com