Re: [PATCH v3 13/15] media: sunxi: Add support for the A83T MIPI CSI-2 controller

From: Maxime Ripard <maxime@cerno.tech>
To: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Cc: linux-media@vger.kernel.org, devicetree@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org,
	devel@driverdev.osuosl.org, linux-sunxi@googlegroups.com,
	Yong Deng <yong.deng@magewell.com>,
	Mauro Carvalho Chehab <mchehab@kernel.org>,
	Rob Herring <robh+dt@kernel.org>, Chen-Yu Tsai <wens@csie.org>,
	Jernej Skrabec <jernej.skrabec@siol.net>,
	Jonathan Corbet <corbet@lwn.net>,
	Kishon Vijay Abraham I <kishon@ti.com>,
	Vinod Koul <vkoul@kernel.org>,
	Helen Koike <helen.koike@collabora.com>,
	Dafna Hirschfeld <dafna.hirschfeld@collabora.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Philipp Zabel <p.zabel@pengutronix.de>,
	Sakari Ailus <sakari.ailus@linux.intel.com>,
	Hans Verkuil <hans.verkuil@cisco.com>,
	Thomas Petazzoni <thomas.petazzoni@bootlin.com>,
	kevin.lhopital@hotmail.com
Subject: Re: [PATCH v3 13/15] media: sunxi: Add support for the A83T MIPI CSI-2 controller
Date: Mon, 14 Dec 2020 12:41:59 +0100	[thread overview]
Message-ID: <20201214114159.oqb4o5fdnnmr4n5q@gilmour> (raw)
In-Reply-To: <20201211155708.154710-14-paul.kocialkowski@bootlin.com>

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On Fri, Dec 11, 2020 at 04:57:06PM +0100, Paul Kocialkowski wrote:
> The A83T supports MIPI CSI-2 with a composite controller, covering
> both the protocol logic and the D-PHY implementation. This controller
> seems to be found on the A83T only and probably was abandoned since.
> 
> This implementation splits the protocol and D-PHY registers and
> uses the PHY framework internally. The D-PHY is not registered as a
> standalone PHY driver since it cannot be used with any other
> controller.
> 
> There are a few notable points about the controller:
> - The initialisation sequence involes writing specific magic init
>   values that do not seem to make any particular sense given the
>   concerned register fields;
> - Interrupts appear to be hitting regardless of the interrupt mask
>   registers, which can cause a serious flood when transmission errors
>   occur.
> 
> Only 8-bit and 10-bit Bayer formats are currently supported.
> While up to 4 internal channels to the CSI controller exist, only one
> is currently supported by this implementation.
> 
> This work is based on the first version of the driver submitted by
> Kévin L'hôpital, which was adapted to mainline from the Allwinner BSP.
> This version integrates MIPI CSI-2 support as a standalone V4L2 subdev
> instead of merging it in the sun6i-csi driver.
> 
> It was tested on a Banana Pi M3 board with an OV8865 sensor in a 4-lane
> configuration.
> 
> Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
> ---
>  arch/arm/boot/dts/sun8i-a83t-bananapi-m3.dts  |   2 +-
>  drivers/media/platform/sunxi/Kconfig          |   1 +
>  drivers/media/platform/sunxi/Makefile         |   1 +
>  .../sunxi/sun8i-a83t-mipi-csi2/Kconfig        |  11 +
>  .../sunxi/sun8i-a83t-mipi-csi2/Makefile       |   4 +
>  .../sun8i-a83t-mipi-csi2/sun8i_a83t_dphy.c    |  92 +++
>  .../sun8i-a83t-mipi-csi2/sun8i_a83t_dphy.h    |  39 ++
>  .../sun8i_a83t_mipi_csi2.c                    | 657 ++++++++++++++++++
>  .../sun8i_a83t_mipi_csi2.h                    | 197 ++++++
>  9 files changed, 1003 insertions(+), 1 deletion(-)
>  create mode 100644 drivers/media/platform/sunxi/sun8i-a83t-mipi-csi2/Kconfig
>  create mode 100644 drivers/media/platform/sunxi/sun8i-a83t-mipi-csi2/Makefile
>  create mode 100644 drivers/media/platform/sunxi/sun8i-a83t-mipi-csi2/sun8i_a83t_dphy.c
>  create mode 100644 drivers/media/platform/sunxi/sun8i-a83t-mipi-csi2/sun8i_a83t_dphy.h
>  create mode 100644 drivers/media/platform/sunxi/sun8i-a83t-mipi-csi2/sun8i_a83t_mipi_csi2.c
>  create mode 100644 drivers/media/platform/sunxi/sun8i-a83t-mipi-csi2/sun8i_a83t_mipi_csi2.h
> 
> diff --git a/arch/arm/boot/dts/sun8i-a83t-bananapi-m3.dts b/arch/arm/boot/dts/sun8i-a83t-bananapi-m3.dts
> index b437eaeb91e9..bebe843a069b 100644
> --- a/arch/arm/boot/dts/sun8i-a83t-bananapi-m3.dts
> +++ b/arch/arm/boot/dts/sun8i-a83t-bananapi-m3.dts
> @@ -151,7 +151,7 @@ port@1 {
>  
>  			csi_in_mipi_csi2: endpoint {
>  				remote-endpoint = <&mipi_csi2_out_csi>;
> -			}
> +			};
>  		};
>  	};
>  };

This looks unrelated?

(and there's the same issue with the macros)

Maxime

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