Re: [PATCH v9 06/13] media: rppx1: awbg: Add support for white balance gain settings

From: Jacopo Mondi

Date: Wed Jun 03 2026 - 09:52:11 EST

Hi Niklas

On Sat, May 16, 2026 at 11:13:13PM +0200, Niklas Söderlund wrote:
> Extend the RPPX1 driver to allow setting the white balance gain
> configuration parameters. It uses the RPPX1 framework for parameters and
> its writer abstraction to allow the user to control how, and when,
> configuration is applied to the RPPX1.
>
> Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@xxxxxxxxxxxx>
> Co-developed-by: Jai Luthra <jai.luthra+renesas@xxxxxxxxxxxxxxxx>
> Signed-off-by: Jai Luthra <jai.luthra+renesas@xxxxxxxxxxxxxxxx>
> Co-developed-by: Jacopo Mondi <jacopo.mondi+renesas@xxxxxxxxxxxxxxxx>
> Signed-off-by: Jacopo Mondi <jacopo.mondi+renesas@xxxxxxxxxxxxxxxx>

Reviewed-by: Jacopo Mondi <jacopo.mondi@xxxxxxxxxxxxxxxx>

Thanks
j

> ---
> .../platform/dreamchip/rppx1/rpp_module.h | 1 +
> .../platform/dreamchip/rppx1/rpp_params.c | 5 +++
> .../platform/dreamchip/rppx1/rppx1_awbg.c | 32 +++++++++++++++
> .../uapi/linux/media/dreamchip/rppx1-config.h | 40 ++++++++++++++++++-
> 4 files changed, 77 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/media/platform/dreamchip/rppx1/rpp_module.h b/drivers/media/platform/dreamchip/rppx1/rpp_module.h
> index 64a1b848f1ea..0e36b717b4ef 100644
> --- a/drivers/media/platform/dreamchip/rppx1/rpp_module.h
> +++ b/drivers/media/platform/dreamchip/rppx1/rpp_module.h
> @@ -47,6 +47,7 @@ void rpp_module_clrset(struct rpp_module *mod, u32 offset, u32 mask, u32 value);
>
> union rppx1_params_block {
> struct v4l2_isp_block_header header;
> + struct rppx1_awbg_params awbg;
> struct rppx1_wbmeas_params wbmeas;
> };
>
> diff --git a/drivers/media/platform/dreamchip/rppx1/rpp_params.c b/drivers/media/platform/dreamchip/rppx1/rpp_params.c
> index 7325abeba92a..17bbcf366970 100644
> --- a/drivers/media/platform/dreamchip/rppx1/rpp_params.c
> +++ b/drivers/media/platform/dreamchip/rppx1/rpp_params.c
> @@ -17,6 +17,8 @@
>
> static const struct v4l2_isp_params_block_type_info
> rppx1_ext_params_blocks_info[] = {
> + RPPX1_PARAMS_BLOCK_INFO(AWBG_PRE1, awbg),
> + RPPX1_PARAMS_BLOCK_INFO(AWBG_PRE2, awbg),
> RPPX1_PARAMS_BLOCK_INFO(WBMEAS_POST, wbmeas),
> };
>
> @@ -51,6 +53,9 @@ int rppx1_params(struct rppx1 *rpp, struct vb2_buffer *vb, size_t max_size,
> block_offset += block->header.size;
>
> switch (block->header.type) {
> + case RPPX1_PARAMS_BLOCK_TYPE_AWBG_PRE1:
> + module = &rpp->pre1.awbg;
> + break;
> case RPPX1_PARAMS_BLOCK_TYPE_WBMEAS_POST:
> module = &rpp->post.wbmeas;
> break;
> diff --git a/drivers/media/platform/dreamchip/rppx1/rppx1_awbg.c b/drivers/media/platform/dreamchip/rppx1/rppx1_awbg.c
> index 4a242b41142b..f30e12d6f880 100644
> --- a/drivers/media/platform/dreamchip/rppx1/rppx1_awbg.c
> +++ b/drivers/media/platform/dreamchip/rppx1/rppx1_awbg.c
> @@ -26,6 +26,38 @@ static int rppx1_awbg_probe(struct rpp_module *mod)
> return 0;
> }
>
> +static int
> +rppx1_awbg_fill_params(struct rpp_module *mod,
> + const union rppx1_params_block *block,
> + rppx1_reg_write write, void *priv)
> +{
> + const struct rppx1_awbg_params *cfg = &block->awbg;
> +
> + /* If the modules is disabled, simply bypass it. */
> + if (cfg->header.flags & V4L2_ISP_PARAMS_FL_BLOCK_DISABLE) {
> + write(priv, mod->base + AWB_ENABLE_REG, 0);
> + return 0;
> + }
> +
> + /*
> + * RPP gains are 18-bit with 12 bit fractional part and 0x1000 = 1.0,
> + * giving a possible range of 0.0 to 64.0. NOTE: RPP documentation is
> + * contradictory this is the register definition, the function
> + * description states 0x400 = 1.0 AND 18-bit with 12 fractional bits,
> + * which is not possible...
> + */
> +
> + write(priv, mod->base + AWB_GAIN_GR_REG, cfg->gain_green_r);
> + write(priv, mod->base + AWB_GAIN_GB_REG, cfg->gain_green_b);
> + write(priv, mod->base + AWB_GAIN_R_REG, cfg->gain_red);
> + write(priv, mod->base + AWB_GAIN_B_REG, cfg->gain_blue);
> +
> + write(priv, mod->base + AWB_ENABLE_REG, AWB_ENABLE_AWB_GAIN_EN);
> +
> + return 0;
> +}
> +
> const struct rpp_module_ops rppx1_awbg_ops = {
> .probe = rppx1_awbg_probe,
> + .fill_params = rppx1_awbg_fill_params,
> };
> diff --git a/include/uapi/linux/media/dreamchip/rppx1-config.h b/include/uapi/linux/media/dreamchip/rppx1-config.h
> index 938f8f258f9e..5ed8a335c9de 100644
> --- a/include/uapi/linux/media/dreamchip/rppx1-config.h
> +++ b/include/uapi/linux/media/dreamchip/rppx1-config.h
> @@ -48,9 +48,15 @@ struct rppx1_window {
> * NOTE: Only append to the enumeration as the numbers are uAPI.
> *
> * @RPPX1_PARAMS_BLOCK_TYPE_WBMEAS_POST: AWB Measurement Configuration
> + * @RPPX1_PARAMS_BLOCK_TYPE_AWBG_PRE1: PRE1 pipe White Balance Gains
> + * @RPPX1_PARAMS_BLOCK_TYPE_AWBG_PRE2: PRE2 White Balance Gains
> + * @RPPX1_PARAMS_BLOCK_TYPE_AWBG_POST: MAIN_POST White Balance Gains
> */
> enum rppx1_params_block_type {
> RPPX1_PARAMS_BLOCK_TYPE_WBMEAS_POST,
> + RPPX1_PARAMS_BLOCK_TYPE_AWBG_PRE1,
> + RPPX1_PARAMS_BLOCK_TYPE_AWBG_PRE2,
> + RPPX1_PARAMS_BLOCK_TYPE_AWBG_POST,
> };
>
> /**
> @@ -109,6 +115,35 @@ struct rppx1_wbmeas_params {
> __u32 ccor_offs[3];
> };
>
> +/**
> + * struct rppx1_awbg_params - WB gain configuration
> + *
> + * The RPP-X1 White Balance Gain module is available in the PRE1 and PRE2
> + * pre-fusion pipes and in the MAIN_POST post-fusion pipe. Userspace selects
> + * which pipe to operate by setting the @header.type field to
> + * RPPX1_PARAMS_BLOCK_TYPE_AWBG_PRE1, RPPX1_PARAMS_BLOCK_TYPE_AWBG_PRE2
> + * or RPPX1_PARAMS_BLOCK_TYPE_AWBG_POST.
> + *
> + * The White Balance module allows to specify per-color channel gains, expressed
> + * as unsigned fixed-point values as 18 bits unsigned integers in Q6.12 format
> + * with a maximum of 63.999.
> + *
> + * @header: block header (type = RPPX1_PARAMS_BLOCK_TYPE_AWBG_PRE1 or
> + * type = RPPX1_PARAMS_BLOCK_TYPE_AWBG_PRE2 or
> + * type = RPPX1_PARAMS_BLOCK_TYPE_AWBG_POST)
> + * @gain_red: gain for red component, 18-bit (unsigned Q6.12)
> + * @gain_green_r: gain for green component in red lines, 18-bit (unsigned Q6.12)
> + * @gain_blue: gain for blue component, 18-bit (unsigned Q6.12)
> + * @gain_green_b: gain for green component in blue lines, 18-bit (unsigned Q6.12)
> + */
> +struct rppx1_awbg_params {
> + struct v4l2_isp_params_block_header header;
> + __u32 gain_red;
> + __u32 gain_green_r;
> + __u32 gain_blue;
> + __u32 gain_green_b;
> +};
> +
> /**
> * RPPX1_PARAMS_MAX_SIZE - Maximum size of all RPP-X1 parameter blocks
> *
> @@ -116,7 +151,10 @@ struct rppx1_wbmeas_params {
> * multiple pipes.
> */
> #define RPPX1_PARAMS_MAX_SIZE \
> - (sizeof(struct rppx1_wbmeas_params))
> + (sizeof(struct rppx1_wbmeas_params) + \
> + sizeof(struct rppx1_awbg_params) + \
> + sizeof(struct rppx1_awbg_params) + \
> + sizeof(struct rppx1_awbg_params))
>
> /* ---------------------------------------------------------------------------
> * Statistics Structures
> --
> 2.54.0
>