[RFC PATCH v2 0/2] v4l2-utils: add support for RB v2 in cvt

[RFC PATCH v2 0/2] v4l2-utils: add support for RB v2 in cvt

[Prashant Laddha]

Posting v2 of patches adding support for reduced blanking version 2 in
v4l2-utils. 

Changes compared to v1:
Incorporated comments on v1. Removed an extra option that was added for 
use-rb-v2. Instead, it now allows reduced-blanking = 2 to indicate the
version 2 of reduced blanking.

Prashant Laddha (2):
  v4l2-ctl-modes: add support for reduced blanking version 2
  v4l2-utils: Modify usage for set-dv-timing to support RB V2

 utils/v4l2-ctl/v4l2-ctl-modes.cpp | 63 +++++++++++++++++++++++++++++----------
 utils/v4l2-ctl/v4l2-ctl-stds.cpp  | 19 ++++++------
 utils/v4l2-ctl/v4l2-ctl.h         |  4 +--
 3 files changed, 58 insertions(+), 28 deletions(-)

-- 
1.9.1

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[RFC PATCH v2 1/2] v4l2-ctl-modes: add support for reduced blanking version 2

[Prashant Laddha]

Added support for reduced blanking version 2 (RB V2) in cvt
modeline calculations. Recently, RB V2 support was added to
v4l2-dv-timings. This patch follows up on that work.

Modified calc_cvt/gtf_modeline() api to capture the version of
reduced blanking. Instead of using a flag for reduced-blanking,
it now allows for passing a value to indicate version info.

Cc: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Prashant Laddha <prladdha@cisco.com>
---
 utils/v4l2-ctl/v4l2-ctl-modes.cpp | 63 +++++++++++++++++++++++++++++----------
 utils/v4l2-ctl/v4l2-ctl-stds.cpp  | 12 +++-----
 utils/v4l2-ctl/v4l2-ctl.h         |  4 +--
 3 files changed, 53 insertions(+), 26 deletions(-)

diff --git a/utils/v4l2-ctl/v4l2-ctl-modes.cpp b/utils/v4l2-ctl/v4l2-ctl-modes.cpp
index 7768998..88f7b6a 100644
--- a/utils/v4l2-ctl/v4l2-ctl-modes.cpp
+++ b/utils/v4l2-ctl/v4l2-ctl-modes.cpp
@@ -52,6 +52,7 @@ static bool valid_params(int width, int height, int refresh_rate)
  */
 
 #define CVT_PXL_CLK_GRAN    (250000)  /* pixel clock granularity */
+#define CVT_PXL_CLK_GRAN_RB_V2 (1000)	/* granularity for reduced blanking v2*/
 
 /* Normal blanking */
 #define CVT_MIN_V_BPORCH     (7)  /* lines */
@@ -77,6 +78,12 @@ static bool valid_params(int width, int height, int refresh_rate)
 #define CVT_RB_H_BPORCH       (80)       /* pixels */
 #define CVT_RB_H_BLANK       (160)       /* pixels */
 
+/* Reduce blanking Version 2 */
+#define CVT_RB_V2_H_BLANK     80       /* pixels */
+#define CVT_RB_MIN_V_FPORCH    3       /* lines  */
+#define CVT_RB_V2_MIN_V_FPORCH 1       /* lines  */
+#define CVT_RB_V_BPORCH        6       /* lines  */
+
 static int v_sync_from_aspect_ratio(int width, int height)
 {
 	if (((height * 4 / 3) / CVT_CELL_GRAN) * CVT_CELL_GRAN == width)
@@ -112,7 +119,8 @@ static int v_sync_from_aspect_ratio(int width, int height)
  * @image_width
  * @image_height
  * @refresh_rate
- * @reduced_blanking: whether to use reduced blanking
+ * @reduced_blanking: This value, if greater than 0, indicates that
+ * reduced blanking is to be used and value indicates the version.
  * @interlaced: whether to compute an interlaced mode
  * @cvt: stores results of cvt timing calculation
  *
@@ -122,7 +130,7 @@ static int v_sync_from_aspect_ratio(int width, int height)
  */
 
 bool calc_cvt_modeline(int image_width, int image_height,
-		       int refresh_rate, bool reduced_blanking,
+		       int refresh_rate, int reduced_blanking,
 		       bool interlaced, struct v4l2_bt_timings *cvt)
 {
 	int h_sync;
@@ -149,10 +157,18 @@ bool calc_cvt_modeline(int image_width, int image_height,
 	int interlace;
 	int v_refresh;
 	int pixel_clock;
+	int clk_gran;
+	bool use_rb = false;
+	bool rb_v2 = false;
 
 	if (!valid_params(image_width, image_height, refresh_rate))
 		return false;
 
+	use_rb = (reduced_blanking > 0) ? true : false;
+	rb_v2 = (reduced_blanking == 2) ? true : false;
+
+	clk_gran = rb_v2 ? CVT_PXL_CLK_GRAN_RB_V2 : CVT_PXL_CLK_GRAN;
+
 	h_pixel = image_width;
 	v_lines = image_height;
 
@@ -187,9 +203,9 @@ bool calc_cvt_modeline(int image_width, int image_height,
 	active_h_pixel = h_pixel_rnd;
 	active_v_lines = v_lines_rnd;
 
-	v_sync = v_sync_from_aspect_ratio(h_pixel, v_lines);
+	v_sync = rb_v2 ? 8 : v_sync_from_aspect_ratio(h_pixel, v_lines);
 
-	if (!reduced_blanking) {
+	if (!use_rb) {
 		int tmp1, tmp2;
 		int ideal_blank_duty_cycle;
 		int v_sync_bp;
@@ -233,12 +249,13 @@ bool calc_cvt_modeline(int image_width, int image_height,
 
 		pixel_clock =  ((long long)total_h_pixel * HV_FACTOR * 1000000)
 				/ h_period;
-		pixel_clock -= pixel_clock  % CVT_PXL_CLK_GRAN;
+		pixel_clock -= pixel_clock  % clk_gran;
 	} else {
 		/* Reduced blanking */
 
 		int vbi_lines;
 		int tmp1, tmp2;
+		int min_vbi_lines;
 
 		/* estimate horizontal period. */
 		tmp1 = HV_FACTOR * 1000000 -
@@ -249,10 +266,15 @@ bool calc_cvt_modeline(int image_width, int image_height,
 
 		vbi_lines = CVT_RB_MIN_V_BLANK * HV_FACTOR / h_period + 1;
 
-		if (vbi_lines < (CVT_RB_V_FPORCH + v_sync + CVT_MIN_V_BPORCH))
-			vbi_lines = CVT_RB_V_FPORCH + v_sync + CVT_MIN_V_BPORCH;
+		if (rb_v2)
+			min_vbi_lines = CVT_RB_V2_MIN_V_FPORCH + v_sync + CVT_RB_V_BPORCH;
+		else
+			min_vbi_lines = CVT_RB_V_FPORCH + v_sync + CVT_MIN_V_BPORCH;
+
+		if (vbi_lines < min_vbi_lines)
+			vbi_lines = min_vbi_lines;
 
-		h_blank = CVT_RB_H_BLANK;
+		h_blank = rb_v2 ? CVT_RB_V2_H_BLANK : CVT_RB_H_BLANK;
 		v_blank = vbi_lines;
 
 		total_h_pixel = active_h_pixel + h_blank;
@@ -263,12 +285,17 @@ bool calc_cvt_modeline(int image_width, int image_height,
 		h_bp = h_blank / 2;
 		h_fp = h_blank - h_bp - h_sync;
 
-		v_fp = CVT_RB_V_FPORCH;
-		v_bp = v_blank - v_fp - v_sync;
+		if (rb_v2) {
+			v_bp = CVT_RB_V_BPORCH;
+			v_fp = v_blank - v_bp - v_sync;
+		} else {
+			v_fp = CVT_RB_V_FPORCH;
+			v_bp = v_blank - v_fp - v_sync;
+		}
 
 		pixel_clock = v_refresh * total_h_pixel *
 			      (2 * total_v_lines + interlace) / 2;
-		pixel_clock -= pixel_clock  % CVT_PXL_CLK_GRAN;
+		pixel_clock -= pixel_clock  % clk_gran;
 	}
 
 	cvt->standards 	 = V4L2_DV_BT_STD_CVT;
@@ -300,7 +327,7 @@ bool calc_cvt_modeline(int image_width, int image_height,
 		cvt->flags |= V4L2_DV_FL_HALF_LINE;
 		cvt->il_vbackporch += 1;
 	}
-	if (reduced_blanking) {
+	if (use_rb) {
 		cvt->polarities = V4L2_DV_HSYNC_POS_POL;
 		cvt->flags |= V4L2_DV_FL_REDUCED_BLANKING;
 	} else
@@ -354,7 +381,8 @@ bool calc_cvt_modeline(int image_width, int image_height,
  * @image_width
  * @image_height
  * @refresh_rate
- * @reduced_blanking: whether to use reduced blanking
+ * @reduced_blanking: This value, if greater than 0, indicates that
+ * reduced blanking is to be used.
  * @interlaced: whether to compute an interlaced mode
  * @gtf: stores results of gtf timing calculation
  *
@@ -364,7 +392,7 @@ bool calc_cvt_modeline(int image_width, int image_height,
  */
 
 bool calc_gtf_modeline(int image_width, int image_height,
-		       int refresh_rate, bool reduced_blanking,
+		       int refresh_rate, int reduced_blanking,
 		       bool interlaced, struct v4l2_bt_timings *gtf)
 {
 	int h_sync;
@@ -397,6 +425,7 @@ bool calc_gtf_modeline(int image_width, int image_height,
 	int v_sync_bp;
 	int tmp1, tmp2;
 	int ideal_blank_duty_cycle;
+	bool use_rb = false;
 
 	if (!gtf) {
 		fprintf(stderr, "Null pointer to gtf modeline structure\n");
@@ -406,6 +435,8 @@ bool calc_gtf_modeline(int image_width, int image_height,
 	if (!valid_params(image_width, image_height, refresh_rate))
 		return false;
 
+	use_rb = (reduced_blanking > 0) ? true : false;
+
 	h_pixel = image_width;
 	v_lines = image_height;
 
@@ -452,7 +483,7 @@ bool calc_gtf_modeline(int image_width, int image_height,
 	h_period = ((long long)h_period_est * v_refresh_est) /
 		   (v_refresh * HV_FACTOR);
 
-	if (!reduced_blanking)
+	if (!use_rb)
 		ideal_blank_duty_cycle = (GTF_D_C_PRIME * HV_FACTOR) -
 				      GTF_D_M_PRIME * h_period / 1000;
 	else
@@ -507,7 +538,7 @@ bool calc_gtf_modeline(int image_width, int image_height,
 		gtf->flags |= V4L2_DV_FL_HALF_LINE;
 		gtf->il_vbackporch += 1;
 	}
-	if (reduced_blanking) {
+	if (use_rb) {
 		gtf->polarities = V4L2_DV_HSYNC_POS_POL;
 		gtf->flags |= V4L2_DV_FL_REDUCED_BLANKING;
 	} else
diff --git a/utils/v4l2-ctl/v4l2-ctl-stds.cpp b/utils/v4l2-ctl/v4l2-ctl-stds.cpp
index e725fa8..3e54ff6 100644
--- a/utils/v4l2-ctl/v4l2-ctl-stds.cpp
+++ b/utils/v4l2-ctl/v4l2-ctl-stds.cpp
@@ -237,15 +237,11 @@ static void get_cvt_gtf_timings(char *subopt, int standard,
 	}
 
 	if (standard == V4L2_DV_BT_STD_CVT) {
-		timings_valid = calc_cvt_modeline(width, height, fps,
-			              r_blank == 1 ? true : false,
-			              interlaced == 1 ? true : false,
-			              bt);
+		timings_valid = calc_cvt_modeline(width, height, fps, r_blank,
+						  interlaced == 1 ? true : false, bt);
 	} else {
-		timings_valid = calc_gtf_modeline(width, height, fps,
-			              r_blank == 1 ? true : false,
-			              interlaced == 1 ? true : false,
-			              bt);
+		timings_valid = calc_gtf_modeline(width, height, fps, r_blank,
+						  interlaced == 1 ? true : false, bt);
 	}
 
 	if (!timings_valid) {
diff --git a/utils/v4l2-ctl/v4l2-ctl.h b/utils/v4l2-ctl/v4l2-ctl.h
index efb5eb3..de65900 100644
--- a/utils/v4l2-ctl/v4l2-ctl.h
+++ b/utils/v4l2-ctl/v4l2-ctl.h
@@ -350,10 +350,10 @@ void edid_get(int fd);
 
 /* v4l2-ctl-modes.cpp */
 bool calc_cvt_modeline(int image_width, int image_height,
-		       int refresh_rate, bool reduced_blanking,
+		       int refresh_rate, int reduced_blanking,
 		       bool interlaced, struct v4l2_bt_timings *cvt);
 
 bool calc_gtf_modeline(int image_width, int image_height,
-		       int refresh_rate, bool reduced_blanking,
+		       int refresh_rate, int reduced_blanking,
 		       bool interlaced, struct v4l2_bt_timings *gtf);
 #endif
-- 
1.9.1

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[RFC PATCH v2 2/2] v4l2-utils: Modify usage for set-dv-timing to support RB V2

[Prashant Laddha]

To support the timings calculations for reduced blanking version 2
(RB v2), command line options now capture version info. Updated the
command usage for the same.

Cc: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Prashant Laddha <prladdha@cisco.com>
---
 utils/v4l2-ctl/v4l2-ctl-stds.cpp | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/utils/v4l2-ctl/v4l2-ctl-stds.cpp b/utils/v4l2-ctl/v4l2-ctl-stds.cpp
index 3e54ff6..aea46c9 100644
--- a/utils/v4l2-ctl/v4l2-ctl-stds.cpp
+++ b/utils/v4l2-ctl/v4l2-ctl-stds.cpp
@@ -41,7 +41,11 @@ void stds_usage(void)
 	       "                     index=<index>: use the index as provided by --list-dv-timings\n"
 	       "                     or specify timings using cvt/gtf options as follows:\n"
 	       "                     cvt/gtf,width=<width>,height=<height>,fps=<frames per sec>\n"
-	       "                     interlaced=<0/1>,reduced-blanking=<0/1>\n"
+	       "                     interlaced=<0/1>,reduced-blanking=<0/1/2>\n"
+	       "                     The value of reduced-blanking, if greater than 0, indicates\n"
+	       "                     that reduced blanking is to be used and the value indicate the\n"
+	       "                     version. For gtf, there is no version 2 for reduced blanking, and\n"
+	       "		     the value 1 or 2 will give same results.\n"
 	       "                     or give a fully specified timings:\n"
 	       "                     width=<width>,height=<height>,interlaced=<0/1>,\n"
 	       "                     polarities=<polarities mask>,pixelclock=<pixelclock Hz>,\n"
@@ -205,7 +209,6 @@ static void get_cvt_gtf_timings(char *subopt, int standard,
 	int fps = 0;
 	int r_blank = 0;
 	int interlaced = 0;
-
 	bool timings_valid = false;
 
 	char *subopt_str = subopt;
-- 
1.9.1

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