media: staging: rkisp1: improve documentation in file rkisp1-config.h

There is some missing documentation of structs and
fields in rkisp1-config.h. This patch improves the
documentation.

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>

1 files changed, 103 insertions, 24 deletions

diff --git a/drivers/staging/media/rkisp1/uapi/rkisp1-config.h b/drivers/staging/media/rkisp1/uapi/rkisp1-config.h
index 76991b0073bb..6894ec768286 100644
--- a/drivers/staging/media/rkisp1/uapi/rkisp1-config.h
+++ b/drivers/staging/media/rkisp1/uapi/rkisp1-config.h
@@ -4,11 +4,6 @@
  * Copyright (C) 2017 Rockchip Electronics Co., Ltd.
  */
 
-/*
- * TODO: Improve documentation, mostly regarding abbreviation and hardware
- * specificities. Reference: "REF_01 - ISP_user_manual, Rev 2.57" (not public)
- */
-
 #ifndef _UAPI_RKISP1_CONFIG_H
 #define _UAPI_RKISP1_CONFIG_H
 
@@ -18,23 +13,41 @@
 #define V4L2_META_FMT_RK_ISP1_PARAMS   v4l2_fourcc('R', 'K', '1', 'P') /* Rockchip ISP1 params */
 #define V4L2_META_FMT_RK_ISP1_STAT_3A  v4l2_fourcc('R', 'K', '1', 'S') /* Rockchip ISP1 3A statistics */
 
+/* Defect Pixel Cluster Detection */
 #define RKISP1_CIF_ISP_MODULE_DPCC		BIT(0)
+/* Black Level Subtraction */
 #define RKISP1_CIF_ISP_MODULE_BLS		BIT(1)
+/* Sensor De-gamma */
 #define RKISP1_CIF_ISP_MODULE_SDG		BIT(2)
+/* Histogram */
 #define RKISP1_CIF_ISP_MODULE_HST		BIT(3)
+/* Lens Shade Control */
 #define RKISP1_CIF_ISP_MODULE_LSC		BIT(4)
+/* Auto White Balance Gain */
 #define RKISP1_CIF_ISP_MODULE_AWB_GAIN		BIT(5)
+/* Filter */
 #define RKISP1_CIF_ISP_MODULE_FLT		BIT(6)
+/* Bayer Demosaic */
 #define RKISP1_CIF_ISP_MODULE_BDM		BIT(7)
+/* Cross Talk */
 #define RKISP1_CIF_ISP_MODULE_CTK		BIT(8)
+/* Gamma Out Curve */
 #define RKISP1_CIF_ISP_MODULE_GOC		BIT(9)
+/* Color Processing */
 #define RKISP1_CIF_ISP_MODULE_CPROC		BIT(10)
+/* Auto Focus Control */
 #define RKISP1_CIF_ISP_MODULE_AFC		BIT(11)
+/* Auto White Balancing */
 #define RKISP1_CIF_ISP_MODULE_AWB		BIT(12)
+/* Image Effect */
 #define RKISP1_CIF_ISP_MODULE_IE		BIT(13)
+/* Auto Exposure Control */
 #define RKISP1_CIF_ISP_MODULE_AEC		BIT(14)
+/* Wide Dynamic Range */
 #define RKISP1_CIF_ISP_MODULE_WDR		BIT(15)
+/* Denoise Pre-Filter */
 #define RKISP1_CIF_ISP_MODULE_DPF		BIT(16)
+/* Denoise Pre-Filter Strength */
 #define RKISP1_CIF_ISP_MODULE_DPF_STRENGTH	BIT(17)
 
 #define RKISP1_CIF_ISP_CTK_COEFF_MAX            0x100
@@ -84,6 +97,7 @@
  */
 #define RKISP1_CIF_ISP_LSC_GRAD_TBL_SIZE           8
 #define RKISP1_CIF_ISP_LSC_SIZE_TBL_SIZE           8
+
 /*
  * The following matches the tuning process,
  * not the max capabilities of the chip.
@@ -158,6 +172,17 @@ enum rkisp1_cif_isp_exp_meas_mode {
 
 /*---------- PART1: Input Parameters ------------*/
 
+/**
+ * struct rkisp1_cif_isp_window -  measurement window.
+ *
+ * Measurements are calculated per window inside the frame.
+ * This struct represents a window for a measurement.
+ *
+ * @h_offs: the horizontal offset of the window from the left of the frame in pixels.
+ * @v_offs: the vertical offset of the window from the top of the frame in pixels.
+ * @h_size: the horizontal size of the window in pixels
+ * @v_size: the vertical size of the window in pixels.
+ */
 struct rkisp1_cif_isp_window {
 	__u16 h_offs;
 	__u16 v_offs;
@@ -247,10 +272,29 @@ struct rkisp1_cif_isp_dpcc_config {
 	__u32 rnd_offs;
 } __packed;
 
+/**
+ * struct rkisp1_cif_isp_gamma_corr_curve - gamma curve point definition y-axis (output).
+ *
+ * The reset values define a linear curve which has the same effect as bypass. Reset values are:
+ * gamma_y[0] = 0x0000, gamma_y[1] = 0x0100, ... gamma_y[15] = 0x0f00, gamma_y[16] = 0xfff
+ *
+ * @gamma_y: the values for the y-axis of gamma curve points. Each value is 12 bit.
+ */
 struct rkisp1_cif_isp_gamma_corr_curve {
 	__u16 gamma_y[RKISP1_CIF_ISP_DEGAMMA_CURVE_SIZE];
 } __packed;
 
+/**
+ * struct rkisp1_cif_isp_gamma_curve_x_axis_pnts - De-Gamma Curve definition x increments
+ *		(sampling points). gamma_dx0 is for the lower samples (1-8), gamma_dx1 is for the
+ *		higher samples (9-16). The reset values for both fields is 0x44444444. This means
+ *		that each sample is 4 units away from the previous one on the x-axis.
+ *
+ * @gamma_dx0: gamma curve sample points definitions. Bits 0:2 for sample 1. Bit 3 unused.
+ *		Bits 4:6 for sample 2. bit 7 unused ... Bits 28:30 for sample 8. Bit 31 unused
+ * @gamma_dx1: gamma curve sample points definitions. Bits 0:2 for sample 9. Bit 3 unused.
+ *		Bits 4:6 for sample 10. bit 7 unused ... Bits 28:30 for sample 16. Bit 31 unused
+ */
 struct rkisp1_cif_isp_gamma_curve_x_axis_pnts {
 	__u32 gamma_dx0;
 	__u32 gamma_dx1;
@@ -259,8 +303,10 @@ struct rkisp1_cif_isp_gamma_curve_x_axis_pnts {
 /**
  * struct rkisp1_cif_isp_sdg_config - Configuration used by sensor degamma
  *
- * @curve_x: gamma curve point definition axis for x
- * @xa_pnts: x increments
+ * @curve_r: gamma curve point definition axis for red
+ * @curve_g: gamma curve point definition axis for green
+ * @curve_b: gamma curve point definition axis for blue
+ * @xa_pnts: x axis increments
  */
 struct rkisp1_cif_isp_sdg_config {
 	struct rkisp1_cif_isp_gamma_corr_curve curve_r;
@@ -272,7 +318,16 @@ struct rkisp1_cif_isp_sdg_config {
 /**
  * struct rkisp1_cif_isp_lsc_config - Configuration used by Lens shading correction
  *
- * refer to REF_01 for details
+ * @r_data_tbl: sample table red
+ * @gr_data_tbl: sample table green (red)
+ * @gb_data_tbl: sample table green (blue)
+ * @b_data_tbl: sample table blue
+ * @x_grad_tbl: gradient table x
+ * @y_grad_tbl: gradient table y
+ * @x_size_tbl: size table x
+ * @y_size_tbl: size table y
+ * @config_width: not used at the moment
+ * @config_height: not used at the moment
  */
 struct rkisp1_cif_isp_lsc_config {
 	__u32 r_data_tbl[RKISP1_CIF_ISP_LSC_DATA_TBL_SIZE];
@@ -292,6 +347,11 @@ struct rkisp1_cif_isp_lsc_config {
 /**
  * struct rkisp1_cif_isp_ie_config - Configuration used by image effects
  *
+ * @effect: values from 'enum v4l2_colorfx'. Possible values are: V4L2_COLORFX_SEPIA,
+ *		V4L2_COLORFX_SET_CBCR, V4L2_COLORFX_AQUA, V4L2_COLORFX_EMBOSS,
+ *		V4L2_COLORFX_SKETCH,   V4L2_COLORFX_BW,   V4L2_COLORFX_NEGATIVE
+ * @color_sel: bits 0:2 - colors bitmask (001 - blue, 010 - green, 100 - red).
+ *		bits 8:15 - Threshold value of the RGB colors for the color selection effect.
  * @eff_mat_1: 3x3 Matrix Coefficients for Emboss Effect 1
  * @eff_mat_2: 3x3 Matrix Coefficients for Emboss Effect 2
  * @eff_mat_3: 3x3 Matrix Coefficients for Emboss 3/Sketch 1
@@ -335,8 +395,8 @@ struct rkisp1_cif_isp_cproc_config {
 /**
  * struct rkisp1_cif_isp_awb_meas_config - Configuration used by auto white balance
  *
+ * @awb_mode: the awb meas mode. From enum rkisp1_cif_isp_awb_mode_type.
  * @awb_wnd: white balance measurement window (in pixels)
- *	     (from enum rkisp1_cif_isp_awb_mode_type)
  * @max_y: only pixels values < max_y contribute to awb measurement, set to 0
  *	   to disable this feature
  * @min_y: only pixels values > min_y contribute to awb measurement
@@ -348,6 +408,7 @@ struct rkisp1_cif_isp_cproc_config {
  *	    (ucFrames=0 means 1 Frame)
  * @awb_ref_cr: reference Cr value for AWB regulation, target for AWB
  * @awb_ref_cb: reference Cb value for AWB regulation, target for AWB
+ * @enable_ymax_cmp: enable Y_MAX compare (Not valid in RGB measurement mode.)
  */
 struct rkisp1_cif_isp_awb_meas_config {
 	/*
@@ -368,7 +429,15 @@ struct rkisp1_cif_isp_awb_meas_config {
 /**
  * struct rkisp1_cif_isp_awb_gain_config - Configuration used by auto white balance gain
  *
- * out_data_x = ( AWB_GEAIN_X * in_data + 128) >> 8
+ * All fields in this struct are 10 bit, where:
+ * 0x100h = 1, unsigned integer value, range 0 to 4 with 8 bit fractional part.
+ *
+ * out_data_x = ( AWB_GAIN_X * in_data + 128) >> 8
+ *
+ * @gain_red: gain value for red component.
+ * @gain_green_r: gain value for green component in red line.
+ * @gain_blue: gain value for blue component.
+ * @gain_green_b: gain value for green component in blue line.
  */
 struct rkisp1_cif_isp_awb_gain_config {
 	__u16 gain_red;
@@ -380,14 +449,24 @@ struct rkisp1_cif_isp_awb_gain_config {
 /**
  * struct rkisp1_cif_isp_flt_config - Configuration used by ISP filtering
  *
- * @mode: ISP_FILT_MODE register fields (from enum rkisp1_cif_isp_flt_mode)
- * @grn_stage1: ISP_FILT_MODE register fields
- * @chr_h_mode: ISP_FILT_MODE register fields
- * @chr_v_mode: ISP_FILT_MODE register fields
+ * All 4 threshold fields (thresh_*) are 10 bits.
+ * All 6 factor fields (fac_*) are 6 bits.
  *
- * refer to REF_01 for details.
+ * @mode: ISP_FILT_MODE register fields (from enum rkisp1_cif_isp_flt_mode)
+ * @grn_stage1: Green filter stage 1 select (range 0x0...0x8)
+ * @chr_h_mode: Chroma filter horizontal mode
+ * @chr_v_mode: Chroma filter vertical mode
+ * @thresh_bl0: If thresh_bl1 < sum_grad < thresh_bl0 then fac_bl0 is selected (blurring th)
+ * @thresh_bl1: If sum_grad < thresh_bl1 then fac_bl1 is selected (blurring th)
+ * @thresh_sh0: If thresh_sh0 < sum_grad < thresh_sh1 then thresh_sh0 is selected (sharpening th)
+ * @thresh_sh1: If thresh_sh1 < sum_grad then thresh_sh1 is selected (sharpening th)
+ * @lum_weight: Parameters for luminance weight function.
+ * @fac_sh1: filter factor for sharp1 level
+ * @fac_sh0: filter factor for sharp0 level
+ * @fac_mid: filter factor for mid level and for static filter mode
+ * @fac_bl0: filter factor for blur 0 level
+ * @fac_bl1: filter factor for blur 1 level (max blur)
  */
-
 struct rkisp1_cif_isp_flt_config {
 	__u32 mode;
 	__u8 grn_stage1;
@@ -748,8 +827,8 @@ struct rkisp1_cif_isp_ae_stat {
 /**
  * struct rkisp1_cif_isp_af_meas_val - AF measured values
  *
- * @sum: sharpness, refer to REF_01 for definition
- * @lum: luminance, refer to REF_01 for definition
+ * @sum: sharpness value
+ * @lum: luminance value
  */
 struct rkisp1_cif_isp_af_meas_val {
 	__u32 sum;
@@ -781,12 +860,12 @@ struct rkisp1_cif_isp_hist_stat {
 } __packed;
 
 /**
- * struct rkisp1_stat_buffer - Rockchip ISP1 Statistics Data
+ * struct rkisp1_cif_isp_stat - Rockchip ISP1 Statistics Data
  *
- * @rkisp1_cif_isp_awb_stat: statistics data for automatic white balance
- * @rkisp1_cif_isp_ae_stat: statistics data for auto exposure
- * @rkisp1_cif_isp_af_stat: statistics data for auto focus
- * @rkisp1_cif_isp_hist_stat: statistics histogram data
+ * @awb: statistics data for automatic white balance
+ * @ae: statistics data for auto exposure
+ * @af: statistics data for auto focus
+ * @hist: statistics histogram data
  */
 struct rkisp1_cif_isp_stat {
 	struct rkisp1_cif_isp_awb_stat awb;
@@ -798,7 +877,7 @@ struct rkisp1_cif_isp_stat {
 /**
  * struct rkisp1_stat_buffer - Rockchip ISP1 Statistics Meta Data
  *
- * @meas_type: measurement types (RKISP1_CIF_ISP_STAT_ definitions)
+ * @meas_type: measurement types (RKISP1_CIF_ISP_STAT_* definitions)
  * @frame_id: frame ID for sync
  * @params: statistics data
  */