Re: [PATCH v2 0/6] UHS-I support for sh_mobile_sdhi

From: Ben Hutchings <ben.hutchings@codethink.co.uk>
To: Ulf Hansson <ulf.hansson@linaro.org>
Cc: Ian Molton <ian@mnementh.co.uk>,
	linux-mmc <linux-mmc@vger.kernel.org>,
	Linux-sh list <linux-sh@vger.kernel.org>,
	"linux-gpio@vger.kernel.org" <linux-gpio@vger.kernel.org>,
	linux-kernel@lists.codethink.co.uk,
	Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>,
	Simon Horman <horms@verge.net.au>,
	Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>,
	Linus Walleij <linus.walleij@linaro.org>
Subject: Re: [PATCH v2 0/6] UHS-I support for sh_mobile_sdhi
Date: Wed, 10 Jun 2015 23:57:57 +0000	[thread overview]
Message-ID: <1433980677.12074.74.camel@codethink.co.uk> (raw)
In-Reply-To: <CAPDyKFq+fZrH1hMdMd8FEzy8h1U9pu8PbaMQtBDOEe+UySqJkA@mail.gmail.com>

On Wed, 2015-06-10 at 11:16 +0200, Ulf Hansson wrote:
> On 10 June 2015 at 01:21, Ben Hutchings <ben.hutchings@codethink.co.uk> wrote:
> > This series adds support for UHS-I in sh_mobile_sdhi, partly implemented
> > in tmio_mmc.  This does not yet include tuning for SDR-104, but SDR-50 now
> > works on the R8A7790 Lager board and another development board.
> >
> > The pfc block needs to be reconfigured from 3.3V to 1.8V signalling on
> > the pins wired to the SD card.  This is supported by adding separate
> > functions for 1.8V signalling in sh-pfc ("sdhi0_1v8" etc.).  I expect
> > that several SH SoCs have this capability, but I only have the R8A7790
> > data sheet so I only implemented it for that one.
> >
> > Changes since v1:
> > - Reword commit message for "mmc: tmio: Add UHS-I mode support"
> > - Make sh_mobile_sdhi_start_signal_voltage_switch() succeed if asked
> >   to switch to 3.3V and the regulator or pinctrl or pinctrl state is
> >   missing
> > - Drop change to mmcif clock on Lager
> > - Correct original author for sdhi clock changes on Lager
> >
> > Changes since the RFC:
> > - Replace the 'regulator' devices for signal voltage switching with
> >   pinctrl functions and states
> > - Drop 'mmc: sh_mobile_sdhi: Add actual clock rate support' as it's
> >   redundant
> > - Use a switch statement in sh_mobile_sdhi_start_signal_voltage_switch()
> > - Fix subject prefix for the DT changes
> >
> > Ben.
> >
> > Ben Hutchings (5):
> >   mmc: tmio: Add UHS-I mode support
> >   pinctrl: sh-pfc: Add set_mux operation to struct sh_pfc_function
> >   pinctrl: sh-pfc: r8a7790: Add separate functions for SDHI 1.8V
> >     operation
> >   mmc: sh_mobile_sdhi: Add UHS-I mode support
> >   ARM: shmobile: lager: Enable UHS-I SDR-50
> >
> > Ian Molton (1):
> >   ARM: shmobile: lager: Set clock rates for SDHI
> >
> >  arch/arm/boot/dts/r8a7790-lager.dts  | 24 +++++++++++--
> >  drivers/mmc/host/sh_mobile_sdhi.c    | 60 +++++++++++++++++++++++++++++++
> >  drivers/mmc/host/tmio_mmc.h          |  3 ++
> >  drivers/mmc/host/tmio_mmc_pio.c      | 31 ++++++++++++++++
> >  drivers/pinctrl/sh-pfc/core.c        |  2 +-
> >  drivers/pinctrl/sh-pfc/core.h        |  1 +
> >  drivers/pinctrl/sh-pfc/pfc-r8a7790.c | 70 +++++++++++++++++++++++++++++++++---
> >  drivers/pinctrl/sh-pfc/pinctrl.c     |  4 +++
> >  drivers/pinctrl/sh-pfc/sh_pfc.h      | 10 +++++-
> >  9 files changed, 197 insertions(+), 8 deletions(-)
> >
> > --
> > 2.1.4
> >
> 
> Hi Ben,
> 
> I have looked at the mmc patches, those looks good to me. Regarding
> the pinctrl and ARM patches, I suppose these can be taken through
> their respective trees and I can take the mmc patches?

The problem with that is that I think the device tree change will cause
a regression if it's applied without the driver changes.  I would much
prefer if I could get the pinctrl and device tree changes acked by the
respective maintainers to go through the MMC tree.  (I should probably
have said that up front.)

> BTW, I noticed that the pinctrl maintainer wasn't in the to-field, you
> may need to repost.

I have the relevant _list_ (linux-gpio) in cc and thought that would be
sufficient, but maybe not, so cc'ing this message.

Ben.