[PATCH v6 08/12] media: rppx1: Add support for Color Correction Matrix

From: Niklas Söderlund

Date: Sat Mar 14 2026 - 18:12:07 EST


Extend the RPPX1 driver to allow setting the Color Correction Matrix
(CTK) configuration using the RkISP1 parameter buffer format. 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.

As the RkISP1 parameters buffer have lower precision then the RPPX1
hardware the values needs to be scaled. The behavior matches the RkISP1
hardware.

Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@xxxxxxxxxxxx>
Tested-by: Marek Vasut <marek.vasut+renesas@xxxxxxxxxxx>
---
* Changes since v5
- Fix commit message.
---
.../platform/dreamchip/rppx1/rpp_params.c | 4 +
.../platform/dreamchip/rppx1/rppx1_ccor.c | 74 +++++++++++++++++++
2 files changed, 78 insertions(+)

diff --git a/drivers/media/platform/dreamchip/rppx1/rpp_params.c b/drivers/media/platform/dreamchip/rppx1/rpp_params.c
index c1917585e19b..c807ccfef628 100644
--- a/drivers/media/platform/dreamchip/rppx1/rpp_params.c
+++ b/drivers/media/platform/dreamchip/rppx1/rpp_params.c
@@ -18,6 +18,7 @@ static const struct v4l2_isp_params_block_type_info
rkisp1_ext_params_blocks_info[] = {
RKISP1_PARAMS_BLOCK_INFO(BLS, bls),
RKISP1_PARAMS_BLOCK_INFO(AWB_GAIN, awb_gain),
+ RKISP1_PARAMS_BLOCK_INFO(CTK, ctk),
RKISP1_PARAMS_BLOCK_INFO(AWB_MEAS, awb_meas),
RKISP1_PARAMS_BLOCK_INFO(HST_MEAS, hst),
RKISP1_PARAMS_BLOCK_INFO(AEC_MEAS, aec),
@@ -61,6 +62,9 @@ int rppx1_params(struct rppx1 *rpp, struct vb2_buffer *vb, size_t max_size,
case RKISP1_EXT_PARAMS_BLOCK_TYPE_AWB_GAIN:
module = &rpp->pre1.awbg;
break;
+ case RKISP1_EXT_PARAMS_BLOCK_TYPE_CTK:
+ module = &rpp->post.ccor;
+ break;
case RKISP1_EXT_PARAMS_BLOCK_TYPE_AWB_MEAS:
module = &rpp->post.wbmeas;
break;
diff --git a/drivers/media/platform/dreamchip/rppx1/rppx1_ccor.c b/drivers/media/platform/dreamchip/rppx1/rppx1_ccor.c
index 4754b0bbce0a..0ccaed8ce55d 100644
--- a/drivers/media/platform/dreamchip/rppx1/rppx1_ccor.c
+++ b/drivers/media/platform/dreamchip/rppx1/rppx1_ccor.c
@@ -68,9 +68,83 @@ static int rppx1_ccor_start(struct rpp_module *mod,
return 0;
}

+static int
+rppx1_ccor_param_rkisp1(struct rpp_module *mod,
+ const union rppx1_params_rkisp1_config *block,
+ rppx1_reg_write write, void *priv)
+{
+ const struct rkisp1_ext_params_ctk_config *cfg = &block->ctk;
+
+ /* If the modules is disabled, configure in bypass mode. */
+ if (cfg->header.flags & RKISP1_EXT_PARAMS_FL_BLOCK_DISABLE) {
+ write(priv, mod->base + CCOR_COEFF_REG(0), 0x1000);
+ write(priv, mod->base + CCOR_COEFF_REG(1), 0x0000);
+ write(priv, mod->base + CCOR_COEFF_REG(2), 0x0000);
+
+ write(priv, mod->base + CCOR_COEFF_REG(3), 0x0000);
+ write(priv, mod->base + CCOR_COEFF_REG(4), 0x1000);
+ write(priv, mod->base + CCOR_COEFF_REG(5), 0x0000);
+
+ write(priv, mod->base + CCOR_COEFF_REG(6), 0x0000);
+ write(priv, mod->base + CCOR_COEFF_REG(7), 0x0000);
+ write(priv, mod->base + CCOR_COEFF_REG(8), 0x1000);
+
+ write(priv, mod->base + CCOR_OFFSET_R_REG, 0x00000000);
+ write(priv, mod->base + CCOR_OFFSET_G_REG, 0x00000000);
+ write(priv, mod->base + CCOR_OFFSET_B_REG, 0x00000000);
+
+ return 0;
+ }
+
+ /*
+ * Coefficient n for color correction matrix.
+ *
+ * RkISP1 coefficients are 11-bit signed fixed-point numbers with 4 bit
+ * integer and 7 bit fractional part, ranging from -8 (0x400) to +7.992
+ * (0x3FF). 0 is represented by 0x000 and a coefficient value of 1 as
+ * 0x080.
+ *
+ * RPP gains are 16-bit signed fixed-point numbers with 4 bit integer
+ * and 12 bit fractional part ranging from -8 (0x8000) to +7.9996
+ * (0x7FFF). 0 is represented by 0x0000 and a coefficient value of 1 as
+ * 0x1000.
+ *
+ * Map the RkISP1 value range by left shifting by 5.
+ */
+ write(priv, mod->base + CCOR_COEFF_REG(0), cfg->config.coeff[0][0] << 5);
+ write(priv, mod->base + CCOR_COEFF_REG(1), cfg->config.coeff[0][1] << 5);
+ write(priv, mod->base + CCOR_COEFF_REG(2), cfg->config.coeff[0][2] << 5);
+
+ write(priv, mod->base + CCOR_COEFF_REG(3), cfg->config.coeff[1][0] << 5);
+ write(priv, mod->base + CCOR_COEFF_REG(4), cfg->config.coeff[1][1] << 5);
+ write(priv, mod->base + CCOR_COEFF_REG(5), cfg->config.coeff[1][2] << 5);
+
+ write(priv, mod->base + CCOR_COEFF_REG(6), cfg->config.coeff[2][0] << 5);
+ write(priv, mod->base + CCOR_COEFF_REG(7), cfg->config.coeff[2][1] << 5);
+ write(priv, mod->base + CCOR_COEFF_REG(8), cfg->config.coeff[2][2] << 5);
+
+ /*
+ * Offset for color components correction matrix.
+ *
+ * Values are a two's complement integer with one sign bit.
+ *
+ * The RkISP params are 11-bit while the RPP can be 12, 20 or 24 bit,
+ * all values are excluding the sign bit. Figure out how much we need
+ * to adjust the input parameters.
+ */
+ const unsigned int shift = mod->info.wbmeas.colorbits - 12 + 1;
+
+ write(priv, mod->base + CCOR_OFFSET_R_REG, cfg->config.ct_offset[0] << shift);
+ write(priv, mod->base + CCOR_OFFSET_G_REG, cfg->config.ct_offset[1] << shift);
+ write(priv, mod->base + CCOR_OFFSET_B_REG, cfg->config.ct_offset[2] << shift);
+
+ return 0;
+}
+
const struct rpp_module_ops rppx1_ccor_ops = {
.probe = rppx1_ccor_probe,
.start = rppx1_ccor_start,
+ .param_rkisp1 = rppx1_ccor_param_rkisp1,
};

static int rppx1_ccor_csm_start(struct rpp_module *mod,
--
2.53.0