media: staging: rkisp1: replace 9 coeff* fields with a 3x3 array

The struct rkisp1_cif_isp_ctk_config has 9 fields 'coeff*' for the
3x3 color correction matrix. Replace these fields with one 3x3
array coeff[3][3] and document the field.
Signed-off-by: Dafna Hirschfeld <dafna.hirschfeld@collabora.com>
Acked-by: Helen Koike <helen.koike@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/staging/media/rkisp1/rkisp1-params.c

@@ -402,15 +402,12 @@ static void rkisp1_goc_config(struct rkisp1_params *params,
 static void rkisp1_ctk_config(struct rkisp1_params *params,
 			      const struct rkisp1_cif_isp_ctk_config *arg)
 {
-	rkisp1_write(params->rkisp1, arg->coeff0, RKISP1_CIF_ISP_CT_COEFF_0);
-	rkisp1_write(params->rkisp1, arg->coeff1, RKISP1_CIF_ISP_CT_COEFF_1);
-	rkisp1_write(params->rkisp1, arg->coeff2, RKISP1_CIF_ISP_CT_COEFF_2);
-	rkisp1_write(params->rkisp1, arg->coeff3, RKISP1_CIF_ISP_CT_COEFF_3);
-	rkisp1_write(params->rkisp1, arg->coeff4, RKISP1_CIF_ISP_CT_COEFF_4);
-	rkisp1_write(params->rkisp1, arg->coeff5, RKISP1_CIF_ISP_CT_COEFF_5);
-	rkisp1_write(params->rkisp1, arg->coeff6, RKISP1_CIF_ISP_CT_COEFF_6);
-	rkisp1_write(params->rkisp1, arg->coeff7, RKISP1_CIF_ISP_CT_COEFF_7);
-	rkisp1_write(params->rkisp1, arg->coeff8, RKISP1_CIF_ISP_CT_COEFF_8);
+	unsigned int i, j, k = 0;
+
+	for (i = 0; i < 3; i++)
+		for (j = 0; j < 3; j++)
+			rkisp1_write(params->rkisp1, arg->coeff[i][j],
+				     RKISP1_CIF_ISP_CT_COEFF_0 + 4 * k++);
 	rkisp1_write(params->rkisp1, arg->ct_offset_r,
 		     RKISP1_CIF_ISP_CT_OFFSET_R);
 	rkisp1_write(params->rkisp1, arg->ct_offset_g,

drivers/staging/media/rkisp1/uapi/rkisp1-config.h

@@ -417,19 +417,13 @@ struct rkisp1_cif_isp_bdm_config {
 /**
  * struct rkisp1_cif_isp_ctk_config - Configuration used by Cross Talk correction
  *
- * @coeff: color correction matrix
+ * @coeff: color correction matrix. Values 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.
  * @ct_offset_b: offset for the crosstalk correction matrix
  */
 struct rkisp1_cif_isp_ctk_config {
-	__u16 coeff0;
-	__u16 coeff1;
-	__u16 coeff2;
-	__u16 coeff3;
-	__u16 coeff4;
-	__u16 coeff5;
-	__u16 coeff6;
-	__u16 coeff7;
-	__u16 coeff8;
+	__u16 coeff[3][3];
 	__u16 ct_offset_r;
 	__u16 ct_offset_g;
 	__u16 ct_offset_b;