#include <linux/videodev2.h>
#include <linux/v4l2-dv-timings.h>
#include <media/v4l2-dv-timings.h>
+#include <linux/math64.h>
MODULE_AUTHOR("Hans Verkuil");
MODULE_DESCRIPTION("V4L2 DV Timings Helper Functions");
#define CVT_MIN_V_BPORCH 7 /* lines */
#define CVT_MIN_V_PORCH_RND 3 /* lines */
#define CVT_MIN_VSYNC_BP 550 /* min time of vsync + back porch (us) */
+#define CVT_HSYNC_PERCENT 8 /* nominal hsync as percentage of line */
/* Normal blanking for CVT uses GTF to calculate horizontal blanking */
#define CVT_CELL_GRAN 8 /* character cell granularity */
else
return false;
+ if (hfreq == 0)
+ return false;
+
/* Vertical */
if (reduced_blanking) {
v_fp = CVT_RB_V_FPORCH;
}
image_height = (frame_height - v_fp - vsync - v_bp + 1) & ~0x1;
+ if (image_height < 0)
+ return false;
+
/* Aspect ratio based on vsync */
switch (vsync) {
case 4:
h_bp = h_blank / 2;
frame_width = image_width + h_blank;
- hsync = (frame_width * 8 + 50) / 100;
- hsync = hsync - hsync % CVT_CELL_GRAN;
+ hsync = frame_width * CVT_HSYNC_PERCENT / 100;
+ hsync = (hsync / CVT_CELL_GRAN) * CVT_CELL_GRAN;
h_fp = h_blank - hsync - h_bp;
}
else
return false;
+ if (hfreq == 0)
+ return false;
+
/* Vertical */
v_fp = GTF_V_FP;
v_bp = (GTF_MIN_VSYNC_BP * hfreq + 500000) / 1000000 - vsync;
image_height = (frame_height - v_fp - vsync - v_bp + 1) & ~0x1;
+ if (image_height < 0)
+ return false;
+
if (aspect.numerator == 0 || aspect.denominator == 0) {
aspect.numerator = 16;
aspect.denominator = 9;
image_width = (image_width + GTF_CELL_GRAN/2) & ~(GTF_CELL_GRAN - 1);
/* Horizontal */
- if (default_gtf)
- h_blank = ((image_width * GTF_D_C_PRIME * hfreq) -
- (image_width * GTF_D_M_PRIME * 1000) +
- (hfreq * (100 - GTF_D_C_PRIME) + GTF_D_M_PRIME * 1000) / 2) /
- (hfreq * (100 - GTF_D_C_PRIME) + GTF_D_M_PRIME * 1000);
- else
- h_blank = ((image_width * GTF_S_C_PRIME * hfreq) -
- (image_width * GTF_S_M_PRIME * 1000) +
- (hfreq * (100 - GTF_S_C_PRIME) + GTF_S_M_PRIME * 1000) / 2) /
- (hfreq * (100 - GTF_S_C_PRIME) + GTF_S_M_PRIME * 1000);
+ if (default_gtf) {
+ u64 num;
+ u32 den;
+
+ num = ((image_width * GTF_D_C_PRIME * (u64)hfreq) -
+ ((u64)image_width * GTF_D_M_PRIME * 1000));
+ den = hfreq * (100 - GTF_D_C_PRIME) + GTF_D_M_PRIME * 1000;
+ h_blank = div_u64((num + (den >> 1)), den);
+ } else {
+ u64 num;
+ u32 den;
+
+ num = ((image_width * GTF_S_C_PRIME * (u64)hfreq) -
+ ((u64)image_width * GTF_S_M_PRIME * 1000));
+ den = hfreq * (100 - GTF_S_C_PRIME) + GTF_S_M_PRIME * 1000;
+ h_blank = div_u64((num + (den >> 1)), den);
+ }
- h_blank = h_blank - h_blank % (2 * GTF_CELL_GRAN);
+ h_blank = ((h_blank + GTF_CELL_GRAN) / (2 * GTF_CELL_GRAN)) *
+ (2 * GTF_CELL_GRAN);
frame_width = image_width + h_blank;
pix_clk = (image_width + h_blank) * hfreq;
pix_clk = pix_clk / GTF_PXL_CLK_GRAN * GTF_PXL_CLK_GRAN;
hsync = (frame_width * 8 + 50) / 100;
- hsync = hsync - hsync % GTF_CELL_GRAN;
+ hsync = ((hsync + GTF_CELL_GRAN / 2) / GTF_CELL_GRAN) * GTF_CELL_GRAN;
h_fp = h_blank / 2 - hsync;