[PATCH v1 2/3] ipa: rpi: Add cam_helper for imx415

[David Plowman]

Hi everyone

On Wed, 8 Jan 2025 at 09:03, Naushir Patuck <naush at raspberrypi.com> wrote:
>
> From: Dave Stevenson <dave.stevenson at raspberrypi.com>
>
> As another Starvis sensor, it is near identical to imx290/327.
>
> Signed-off-by: Dave Stevenson <dave.stevenson at raspberrypi.com>
> Signed-off-by: Naushir Patuck <naush at raspberrypi.com>

Reviewed-by: David Plowman <david.plowman at raspberrypi.com>

If it's truly identical I suppose we could have re-registered the
imx290 helper under "imx415". But maybe we don't like that and this is
probably better!

Thanks
David

> ---
>  src/ipa/rpi/cam_helper/cam_helper_imx415.cpp | 64 ++++++++++++++++++++
>  src/ipa/rpi/cam_helper/meson.build           |  1 +
>  2 files changed, 65 insertions(+)
>  create mode 100644 src/ipa/rpi/cam_helper/cam_helper_imx415.cpp
>
> diff --git a/src/ipa/rpi/cam_helper/cam_helper_imx415.cpp b/src/ipa/rpi/cam_helper/cam_helper_imx415.cpp
> new file mode 100644
> index 000000000000..c0a09eee3dee
> --- /dev/null
> +++ b/src/ipa/rpi/cam_helper/cam_helper_imx415.cpp
> @@ -0,0 +1,64 @@
> +/* SPDX-License-Identifier: BSD-2-Clause */
> +/*
> + * Copyright (C) 2025, Raspberry Pi Ltd
> + *
> + * camera helper for imx415 sensor
> + */
> +
> +#include <cmath>
> +
> +#include "cam_helper.h"
> +
> +using namespace RPiController;
> +
> +class CamHelperImx415 : public CamHelper
> +{
> +public:
> +       CamHelperImx415();
> +       uint32_t gainCode(double gain) const override;
> +       double gain(uint32_t gainCode) const override;
> +       unsigned int hideFramesStartup() const override;
> +       unsigned int hideFramesModeSwitch() const override;
> +
> +private:
> +       /*
> +        * Smallest difference between the frame length and integration time,
> +        * in units of lines.
> +        */
> +       static constexpr int frameIntegrationDiff = 8;
> +};
> +
> +CamHelperImx415::CamHelperImx415()
> +       : CamHelper({}, frameIntegrationDiff)
> +{
> +}
> +
> +uint32_t CamHelperImx415::gainCode(double gain) const
> +{
> +       int code = 66.6667 * std::log10(gain);
> +       return std::max(0, std::min(code, 0xf0));
> +}
> +
> +double CamHelperImx415::gain(uint32_t gainCode) const
> +{
> +       return std::pow(10, 0.015 * gainCode);
> +}
> +
> +unsigned int CamHelperImx415::hideFramesStartup() const
> +{
> +       /* On startup, we seem to get 1 bad frame. */
> +       return 1;
> +}
> +
> +unsigned int CamHelperImx415::hideFramesModeSwitch() const
> +{
> +       /* After a mode switch, we seem to get 1 bad frame. */
> +       return 1;
> +}
> +
> +static CamHelper *create()
> +{
> +       return new CamHelperImx415();
> +}
> +
> +static RegisterCamHelper reg("imx415", &create);
> diff --git a/src/ipa/rpi/cam_helper/meson.build b/src/ipa/rpi/cam_helper/meson.build
> index 03e88fe082e2..abf021474b5c 100644
> --- a/src/ipa/rpi/cam_helper/meson.build
> +++ b/src/ipa/rpi/cam_helper/meson.build
> @@ -7,6 +7,7 @@ rpi_ipa_cam_helper_sources = files([
>      'cam_helper_imx283.cpp',
>      'cam_helper_imx290.cpp',
>      'cam_helper_imx296.cpp',
> +    'cam_helper_imx415.cpp',
>      'cam_helper_imx477.cpp',
>      'cam_helper_imx519.cpp',
>      'cam_helper_imx708.cpp',
> --
> 2.43.0
>