[PATCH 02/12] drivers: mfd: Add support for Exynos PMU driver
lee.jones at linaro.org
Tue Nov 4 00:24:02 PST 2014
On Tue, 04 Nov 2014, Pankaj Dubey wrote:
> On Monday, November 03, 2014 8:56 PM, Lee Jones wrote,
> > Subject: Re: [PATCH 02/12] drivers: mfd: Add support for Exynos PMU driver
> > On Mon, 03 Nov 2014, Amit Daniel Kachhap wrote:
> > > From: Pankaj Dubey <pankaj.dubey at samsung.com>
> > >
> > > 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 <sbkim73 at samsung.com>
> > > CC: Samuel Ortiz <sameo at linux.intel.com>
> > > CC: Lee Jones <lee.jones at linaro.org>
> > > Signed-off-by: Pankaj Dubey <pankaj.dubey at samsung.com>
> > > Signed-off-by: Amit Daniel Kachhap <amit.daniel at samsung.com>
> > > ---
> > > arch/arm/mach-exynos/Kconfig | 1 +
> > > arch/arm/mach-exynos/Makefile | 2 +-
> > > drivers/mfd/Kconfig | 9 +++++++++
> > > drivers/mfd/Makefile | 1 +
> > > .../mach-exynos/pmu.c => drivers/mfd/exynos-pmu.c | 0
> > > 5 files changed, 12 insertions(+), 1 deletion(-) rename
> > > arch/arm/mach-exynos/pmu.c => drivers/mfd/exynos-pmu.c (100%)
> > I thought we spoke about this already ? What's changed?
> >  https://lkml.org/lkml/2014/4/29/193
> Yes correct, we had discussion about this in above post. But at that time I was not having enough points to
> put forward for keeping Exynos PMU driver in MFD folder.
There are no valid points for keeping PMU code in MFD.
> At that point there was only one idea behind keeping Exynos PMU that in future it will be reused for ARM64
> based SoC for PM related functionalities.
> But in this series we have implemented Exynos Power Domain for Samsung's ARM64 based SoCs.
> As far as I can see this will in following ways -
> 1: Moving out PM domain specific code from mach-exynos and reuse of same code for ARM64 based SoC also.
> 2: Since PM domain relies on PMU registers and does not have its own DT binding, MFD client and MFD device
> is most suitable for making this kind of platform drivers.
MFD can be used to register the device, but the driver must not live
in MFD. Please relocate it into drivers/power.
Linaro STMicroelectronics Landing Team Lead
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