From mboxrd@z Thu Jan 1 00:00:00 1970 From: lee.jones@linaro.org (Lee Jones) Date: Tue, 29 Apr 2014 10:27:23 +0100 Subject: [RESUBMIT RFC PATCH v2 3/3] drivers: mfd: Add support for Exynos PMU driver In-Reply-To: <535F5AA7.2050001@samsung.com> 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> Message-ID: <20140429092723.GG29462@lee--X1> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org > >>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 PMU IP > >>of Exynos SoC which will be required to configure before Suspend/Resume. > >>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 based > >>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 => drivers/mfd/exynos-pmu.c | 0 > >> 5 files changed, 12 insertions(+), 2 deletions(-) > >> rename arch/arm/mach-exynos/pmu.c => drivers/mfd/exynos-pmu.c (100%) > >So I just took a look at the code as zero changes looks suspicious to > >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? > > Exynos PMU chip controls different power states of Exynos, so mainly it > does power management related stuff. Apart from this it has few registers > which controls PHY of various IP blocks of Exynos such as USB, HDMI, > ADC etc. But these phy controlling register are currently being accessed > 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. -- Lee Jones Linaro STMicroelectronics Landing Team Lead Linaro.org ? Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog