Re: [EXT] Re: [PATCH v6 4/8] phy: Add HDMI configuration options

[Dmitry Baryshkov]

On Mon, 10 Jul 2023 at 10:28, Sandor Yu <sandor.yu@xxxxxxx> wrote:
>
> Hi Dmitry,
>
> Thanks for your comments,
>
> > -----Original Message-----
> > From: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
> > Sent: 2023年6月25日 2:02
> > To: Sandor Yu <sandor.yu@xxxxxxx>; andrzej.hajda@xxxxxxxxx;
> > neil.armstrong@xxxxxxxxxx; robert.foss@xxxxxxxxxx;
> > Laurent.pinchart@xxxxxxxxxxxxxxxx; jonas@xxxxxxxxx;
> > jernej.skrabec@xxxxxxxxx; airlied@xxxxxxxxx; daniel@xxxxxxxx;
> > robh+dt@xxxxxxxxxx; krzysztof.kozlowski+dt@xxxxxxxxxx;
> > shawnguo@xxxxxxxxxx; s.hauer@xxxxxxxxxxxxxx; festevam@xxxxxxxxx;
> > vkoul@xxxxxxxxxx; dri-devel@xxxxxxxxxxxxxxxxxxxxx;
> > devicetree@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx;
> > linux-kernel@xxxxxxxxxxxxxxx; linux-phy@xxxxxxxxxxxxxxxxxxx
> > Cc: kernel@xxxxxxxxxxxxxx; dl-linux-imx <linux-imx@xxxxxxx>; Oliver Brown
> > <oliver.brown@xxxxxxx>
> > Subject: [EXT] Re: [PATCH v6 4/8] phy: Add HDMI configuration options

Is this part necessary?

> >
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> >
> >
> > On 15/06/2023 04:38, Sandor Yu wrote:
> > > Allow HDMI PHYs to be configured through the generic functions through
> > > a custom structure added to the generic union.
> > >
> > > The parameters added here are based on HDMI PHY implementation
> > > practices.  The current set of parameters should cover the potential
> > > users.
> > >
> > > Signed-off-by: Sandor Yu <Sandor.yu@xxxxxxx>
> > > ---
> > >   include/linux/phy/phy-hdmi.h | 38
> > ++++++++++++++++++++++++++++++++++++
> > >   include/linux/phy/phy.h      |  7 ++++++-
> > >   2 files changed, 44 insertions(+), 1 deletion(-)
> > >   create mode 100644 include/linux/phy/phy-hdmi.h
> > >
> > > diff --git a/include/linux/phy/phy-hdmi.h
> > > b/include/linux/phy/phy-hdmi.h new file mode 100644 index
> > > 000000000000..5765aa5bc175
> > > --- /dev/null
> > > +++ b/include/linux/phy/phy-hdmi.h
> > > @@ -0,0 +1,38 @@
> > > +/* SPDX-License-Identifier: GPL-2.0 */
> > > +/*
> > > + * Copyright 2022 NXP
> > > + */
> > > +
> > > +#ifndef __PHY_HDMI_H_
> > > +#define __PHY_HDMI_H_
> > > +
> > > +/**
> > > + * Pixel Encoding as HDMI Specification
> > > + * RGB, YUV422, YUV444:HDMI Specification 1.4a Section 6.5
> > > + * YUV420: HDMI Specification 2.a Section 7.1  */ enum
> > > +hdmi_phy_colorspace {
> > > +     HDMI_PHY_COLORSPACE_RGB,        /* RGB 4:4:4 */
> > > +     HDMI_PHY_COLORSPACE_YUV422,     /* YCbCr 4:2:2 */
> > > +     HDMI_PHY_COLORSPACE_YUV444,     /* YCbCr 4:4:4 */
> > > +     HDMI_PHY_COLORSPACE_YUV420,     /* YCbCr 4:2:0 */
> > > +     HDMI_PHY_COLORSPACE_RESERVED4,
> > > +     HDMI_PHY_COLORSPACE_RESERVED5,
> > > +     HDMI_PHY_COLORSPACE_RESERVED6,
> > > +};
> >
> > This enum duplicates enum hdmi_colorspace from <linux/hdmi.h> HDMI 2.0
> > defines '7' to be IDO-defined.
> >
> > Would it be better to use that enum instead?
> Accept. I will create head file hdmi_colorspace.h to reuse enum hdmi_colorspace in <linux/hdmi.h>.

Hmm, you need another header file to reuse this enum.

>
> B.R
> Sandor
> >
> > > +
> > > +/**
> > > + * struct phy_configure_opts_hdmi - HDMI configuration set
> > > + * @pixel_clk_rate:  Pixel clock of video modes in KHz.
> > > + * @bpc: Maximum bits per color channel.
> > > + * @color_space: Colorspace in enum hdmi_phy_colorspace.
> > > + *
> > > + * This structure is used to represent the configuration state of a HDMI phy.
> > > + */
> > > +struct phy_configure_opts_hdmi {
> > > +     unsigned int pixel_clk_rate;
> > > +     unsigned int bpc;
> > > +     enum hdmi_phy_colorspace color_space; };
> > > +
> > > +#endif /* __PHY_HDMI_H_ */
> >
> > [skipped the rest]
> >
> > --
> > With best wishes
> > Dmitry
>


-- 
With best wishes
Dmitry