diff options
Diffstat (limited to 'include/media/v4l2-dv-timings.h')
-rw-r--r-- | include/media/v4l2-dv-timings.h | 59 |
1 files changed, 59 insertions, 0 deletions
diff --git a/include/media/v4l2-dv-timings.h b/include/media/v4l2-dv-timings.h index 41075fa..4c7bb54 100644 --- a/include/media/v4l2-dv-timings.h +++ b/include/media/v4l2-dv-timings.h @@ -64,4 +64,63 @@ bool v4l2_find_dv_timings_cap(struct v4l2_dv_timings *t, const struct v4l2_dv_timings_cap *cap, unsigned pclock_delta); +/** v4l_match_dv_timings() - do two timings match? + * @measured: the measured timings data. + * @standard: the timings according to the standard. + * @pclock_delta: maximum delta in Hz between standard->pixelclock and + * the measured timings. + * + * Returns true if the two timings match, returns false otherwise. + */ +bool v4l_match_dv_timings(const struct v4l2_dv_timings *measured, + const struct v4l2_dv_timings *standard, + unsigned pclock_delta); + +/** v4l2_detect_cvt - detect if the given timings follow the CVT standard + * @frame_height - the total height of the frame (including blanking) in lines. + * @hfreq - the horizontal frequency in Hz. + * @vsync - the height of the vertical sync in lines. + * @polarities - the horizontal and vertical polarities (same as struct + * v4l2_bt_timings polarities). + * @fmt - the resulting timings. + * + * This function will attempt to detect if the given values correspond to a + * valid CVT format. If so, then it will return true, and fmt will be filled + * in with the found CVT timings. + */ +bool v4l2_detect_cvt(unsigned frame_height, unsigned hfreq, unsigned vsync, + u32 polarities, struct v4l2_dv_timings *fmt); + +/** v4l2_detect_gtf - detect if the given timings follow the GTF standard + * @frame_height - the total height of the frame (including blanking) in lines. + * @hfreq - the horizontal frequency in Hz. + * @vsync - the height of the vertical sync in lines. + * @polarities - the horizontal and vertical polarities (same as struct + * v4l2_bt_timings polarities). + * @aspect - preferred aspect ratio. GTF has no method of determining the + * aspect ratio in order to derive the image width from the + * image height, so it has to be passed explicitly. Usually + * the native screen aspect ratio is used for this. If it + * is not filled in correctly, then 16:9 will be assumed. + * @fmt - the resulting timings. + * + * This function will attempt to detect if the given values correspond to a + * valid GTF format. If so, then it will return true, and fmt will be filled + * in with the found GTF timings. + */ +bool v4l2_detect_gtf(unsigned frame_height, unsigned hfreq, unsigned vsync, + u32 polarities, struct v4l2_fract aspect, + struct v4l2_dv_timings *fmt); + +/** v4l2_calc_aspect_ratio - calculate the aspect ratio based on bytes + * 0x15 and 0x16 from the EDID. + * @hor_landscape - byte 0x15 from the EDID. + * @vert_portrait - byte 0x16 from the EDID. + * + * Determines the aspect ratio from the EDID. + * See VESA Enhanced EDID standard, release A, rev 2, section 3.6.2: + * "Horizontal and Vertical Screen Size or Aspect Ratio" + */ +struct v4l2_fract v4l2_calc_aspect_ratio(u8 hor_landscape, u8 vert_portrait); + #endif |