Re: [PATCH v9 2/2] phy: Add driver for mixel mipi dphy found on NXP's i.MX8 SoCs

From: Guido Günther
Date: Tue Apr 30 2019 - 12:58:30 EST


Hi Fabio,
On Tue, Apr 30, 2019 at 01:24:45PM -0300, Fabio Estevam wrote:
> Hi Guido,
>
> On Tue, Apr 30, 2019 at 11:40 AM Guido Günther <agx@xxxxxxxxxxx> wrote:
> >
> > This adds support for the Mixel DPHY as found on i.MX8 CPUs but since
> > this is an IP core it will likely be found on others in the future. So
> > instead of adding this to the nwl host driver make it a generic PHY
> > driver.
> >
> > The driver supports the i.MX8MQ. Support for i.MX8QM and i.MX8QXP can be
> > added once the necessary system controller bits are in via
> > mixel_dphy_devdata.
> >
> > Co-authored-by: Robert Chiras <robert.chiras@xxxxxxx>
> > Signed-off-by: Guido Günther <agx@xxxxxxxxxxx>
>
> I wish I could test it on a imx8m-evk , but there are some other
> pieces needed such as Northwest Logic driver, mxsfb changes for
> supporting mx8m, OLED panel driver, etc
>
> Anyway, it looks good to me and I have only a few minor comments:
>
> > ---
> > drivers/phy/freescale/Kconfig | 11 +
> > drivers/phy/freescale/Makefile | 1 +
> > .../phy/freescale/phy-fsl-imx8-mipi-dphy.c | 506 ++++++++++++++++++
> > 3 files changed, 518 insertions(+)
> > create mode 100644 drivers/phy/freescale/phy-fsl-imx8-mipi-dphy.c
> >
> > diff --git a/drivers/phy/freescale/Kconfig b/drivers/phy/freescale/Kconfig
> > index 832670b4952b..a111b130f9d2 100644
> > --- a/drivers/phy/freescale/Kconfig
> > +++ b/drivers/phy/freescale/Kconfig
> > @@ -3,3 +3,14 @@ config PHY_FSL_IMX8MQ_USB
> > depends on OF && HAS_IOMEM
> > select GENERIC_PHY
> > default ARCH_MXC && ARM64
> > +
> > +config PHY_MIXEL_MIPI_DPHY
> > + tristate "Mixel MIPI DSI PHY support"
> > + depends on OF && HAS_IOMEM
> > + select GENERIC_PHY
> > + select GENERIC_PHY_MIPI_DPHY
> > + select REGMAP_MMIO
> > + default ARCH_MXC && ARM64
>
> I don't think that this default is a good idea.
>
> There are imx8m systems that do not have display, so in this case it
> does not make sense to always force the build of this driver.

O.k. - we can enable this based on imx-nwl later on. I've also addressed
your other comments. Will wait for a v10 for a couple of days in case
there's more feedback.
Thanks,
-- Guido