From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lee Jones Subject: Re: [RESUBMIT RFC PATCH v2 3/3] drivers: mfd: Add support for Exynos PMU driver Date: Tue, 29 Apr 2014 10:27:23 +0100 Message-ID: <20140429092723.GG29462@lee--X1> References: <1398687607-4554-1-git-send-email-pankaj.dubey@samsung.com> <1398687607-4554-4-git-send-email-pankaj.dubey@samsung.com> <20140428122646.GF21279@lee--X1> <535F5AA7.2050001@samsung.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from mail-wi0-f171.google.com ([209.85.212.171]:43684 "EHLO mail-wi0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752134AbaD2J1a (ORCPT ); Tue, 29 Apr 2014 05:27:30 -0400 Received: by mail-wi0-f171.google.com with SMTP id bs8so871380wib.4 for ; Tue, 29 Apr 2014 02:27:29 -0700 (PDT) Content-Disposition: inline In-Reply-To: <535F5AA7.2050001@samsung.com> Sender: linux-samsung-soc-owner@vger.kernel.org List-Id: linux-samsung-soc@vger.kernel.org To: Pankaj Dubey Cc: linux-samsung-soc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kgene.kim@samsung.com, linux@arm.linux.org.uk, t.figa@samsung.com, chow.kim@samsung.com, yg1004.jang@samsung.com, vikas.sajjan@samsung.com, b.zolnierkie@samsung.com, Sangbeom Kim , Samuel Ortiz > >>This patch moves Exynos PMU driver implementation from > >>"arm/mach-exynos" to "drivers/mfd". > >>This driver is mainly used for setting misc bits of register from P= MU IP > >>of Exynos SoC which will be required to configure before Suspend/Re= sume. > >>Currently all these settings are done in "arch/arm/mach-exynos/pmu.= c" but > >>moving ahead for ARM64 based SoC support, there is a need of DT bas= ed > >>implementation of PMU driver. > >>This driver uses already existing DT binding information. > >> > >>CC: Sangbeom Kim > >>CC: Samuel Ortiz > >>CC: Lee Jones > >>Signed-off-by: Pankaj Dubey > >>--- > >> arch/arm/mach-exynos/Kconfig | 2 ++ > >> arch/arm/mach-exynos/Makefile | 2 -- > >> drivers/mfd/Kconfig | 9 +++= ++++++ > >> drivers/mfd/Makefile | 1 + > >> arch/arm/mach-exynos/pmu.c =3D> drivers/mfd/exynos-pmu.c | 0 > >> 5 files changed, 12 insertions(+), 2 deletions(-) > >> rename arch/arm/mach-exynos/pmu.c =3D> drivers/mfd/exynos-pmu.c (= 100%) > >So I just took a look at the code as zero changes looks suspicious t= o > >me. The driver can not simply be copied and pasted into the MFD > >subsystem in its current state. > > > >The fundamental question is; is this chip actually an MFD? What does > >it do besides Power Management? >=20 > Exynos PMU chip controls different power states of Exynos, so mainly = it > does power management related stuff. Apart from this it has few regis= ters > which controls PHY of various IP blocks of Exynos such as USB, HDMI, > ADC etc. But these phy controlling register are currently being acces= sed > via "syscon" driver provided regmap APIs. For same the same reason > Exynos PMU has second compatibility string as "syscon". I suggest that this is not suitable for the MFD subsystem then. Try drivers/power. --=20 Lee Jones Linaro STMicroelectronics Landing Team Lead Linaro.org =E2=94=82 Open source software for ARM SoCs =46ollow Linaro: Facebook | Twitter | Blog