Re: [RESUBMIT RFC PATCH v2 3/3] drivers: mfd: Add support for Exynos PMU driver

[Catalin Marinas <catalin.marinas@arm.com>]

On Mon, Apr 28, 2014 at 01:26:46PM +0100, Lee Jones wrote:
> > 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@samsung.com>
> > CC: Samuel Ortiz <sameo@linux.intel.com>
> > CC: Lee Jones <lee.jones@linaro.org>
> > Signed-off-by: Pankaj Dubey <pankaj.dubey@samsung.com>
> > ---
> >  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?

I looked at the code briefly as well and I don't think it matches the
mfd idea. Maybe it could be merged together with
arch/arm/mach-exynos/pm.c and moved to drivers/power/ or a more
appropriate directory for platform_suspend_ops.

-- 
Catalin