From mboxrd@z Thu Jan 1 00:00:00 1970 From: Heiko =?iso-8859-1?q?St=FCbner?= Subject: Re: [PATCH] i2c: s3c24xx: allow device core to setup default pin configuration Date: Thu, 21 Mar 2013 11:50:05 +0100 Message-ID: <201303211150.06891.heiko@sntech.de> References: <1362404573-30406-1-git-send-email-thomas.abraham@linaro.org> <20130321100032.GC19297@the-dreams.de> Mime-Version: 1.0 Content-Type: Text/Plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <20130321100032.GC19297-z923LK4zBo2bacvFa/9K2g@public.gmane.org> Sender: linux-i2c-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Wolfram Sang Cc: Thomas Abraham , linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-samsung-soc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linus.walleij-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org, kgene.kim-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org, ben-linux-elnMNo+KYs3YtjvyW6yDsg@public.gmane.org, t.figa-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org List-Id: linux-i2c@vger.kernel.org Am Donnerstag, 21. M=E4rz 2013, 11:00:32 schrieb Wolfram Sang: > On Mon, Mar 04, 2013 at 07:12:53PM +0530, Thomas Abraham wrote: > > With device core now able to setup the default pin configuration, > > the call to devm_pinctrl_get_select_default can be removed. And > > the pin configuration code based on the deprecated Samsung specific > > gpio bindings is also removed. > >=20 > > Signed-off-by: Thomas Abraham > > --- > >=20 > > Hi Heiko, Tomasz, > >=20 > > We have to make a choice on the path forward for pinctrl support > > on Samsung platforms. We have three cases to deal with. > >=20 > > A. Samsung platforms without DT support. > > B. Samsung platforms with DT support using old Samsung specific > >=20 > > gpio bindings for pin-configuration (s3c24xx and s3x64xx). > >=20 > > C. Samsung platforms with DT support using using pinctrl based > >=20 > > pin-configurations (Exynos4 and Exynos5). > >=20 > > For [A], we just let the platform specific callbacks handle the > > pin setup. For [B] and [C], based on Linus Walleij's pin grab > > by device core patch and subsequent discussions with him on the > > mailing list, would it be acceptable that we discontinue support > > for [B] in Samsung SoC device drivers. This will impact your > > current DT work on s3c24xx and s3c64xx platforms. Pinctrl is > > inevitable and we have to migrate to it. Instead of workarounds > > to maintain support for [B], it might be better that we migrate > > s3c24xx and s3c64xx platforms to pinctrl. > >=20 > > Please do let us know your opinion on this. >=20 > Dropping [B] sounds good, but I think it makes sense to wait with thi= s > patch until pinctrl support for s3c24xx is in place? s3c24xx does not currently have dt support in mainline at all and the n= on-dt=20 init is not touched at all. Also it seems the legacy gpio based dt init= does=20 not work at all currently, because the pinctrl function are no-ops and=20 therefore the legacy gpio init is never reached on such systems. So I would vote for dropping [B]. I'm already working a bit on a pinctr= l=20 driver for s3c24xx, so when I reintroduce s3c24xx dt support again, it = should=20 already have pinctrl support then. Heiko