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Message-ID: <6f590bb6-7d17-3ae8-684d-2d4403d6ff55@linaro.org>
Date:   Sat, 24 Jun 2023 21:02:06 +0300
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Subject: Re: [PATCH v6 4/8] phy: Add HDMI configuration options
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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,
        shawnguo@kernel.org, s.hauer@pengutronix.de, festevam@gmail.com,
        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, linux-imx@nxp.com, oliver.brown@nxp.com
References: <cover.1686729444.git.Sandor.yu@nxp.com>
 <cec469206a166c4b070fd7d7bbf89a8df656ccc6.1686729444.git.Sandor.yu@nxp.com>
From:   Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
In-Reply-To: <cec469206a166c4b070fd7d7bbf89a8df656ccc6.1686729444.git.Sandor.yu@nxp.com>
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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?

> +
> +/**
> + * 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