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

[Sandor Yu <sandor.yu@nxp.com>]

Hi Dmitry,

Thanks for your comments,

> -----Original Message-----
> From: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> Sent: 2023年6月25日 2:02
> To: Sandor Yu <sandor.yu@nxp.com>; andrzej.hajda@intel.com;
> neil.armstrong@linaro.org; robert.foss@linaro.org;
> Laurent.pinchart@ideasonboard.com; jonas@kwiboo.se;
> jernej.skrabec@gmail.com; airlied@gmail.com; daniel@ffwll.ch;
> robh+dt@kernel.org; krzysztof.kozlowski+dt@linaro.org;
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> vkoul@kernel.org; dri-devel@lists.freedesktop.org;
> devicetree@vger.kernel.org; linux-arm-kernel@lists.infradead.org;
> linux-kernel@vger.kernel.org; linux-phy@lists.infradead.org
> Cc: kernel@pengutronix.de; dl-linux-imx <linux-imx@nxp.com>; Oliver Brown
> <oliver.brown@nxp.com>
> Subject: [EXT] Re: [PATCH v6 4/8] phy: Add HDMI configuration options
> 
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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@nxp.com>
> > ---
> >   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>.

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