From fb66852d4c693d5159724aef2b0c5e956206940d Mon Sep 17 00:00:00 2001 From: Mauro Carvalho Chehab Date: Tue, 28 Jun 2016 23:17:34 -0300 Subject: [PATCH] [media] tw686x: use a formula instead of two tables for div Instead of using two tables to estimate the temporal decimation factor, use a formula. This allows to get the closest fps, which sounds better than the current tables. Also, the current code doesn't store the real framerate. This patch fixes the above issues. [Ezequiel: - introduce a TW686X_MAX_FPS macro for max_fps. - use hweight_long instead of open coding the set bits count.] Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Ezequiel Garcia Signed-off-by: Mauro Carvalho Chehab --- drivers/media/pci/tw686x/tw686x-video.c | 95 ++++++++++++++++--------- 1 file changed, 61 insertions(+), 34 deletions(-) diff --git a/drivers/media/pci/tw686x/tw686x-video.c b/drivers/media/pci/tw686x/tw686x-video.c index d681bd481bc6..487b078a5acc 100644 --- a/drivers/media/pci/tw686x/tw686x-video.c +++ b/drivers/media/pci/tw686x/tw686x-video.c @@ -28,6 +28,7 @@ #define TW686X_INPUTS_PER_CH 4 #define TW686X_VIDEO_WIDTH 720 #define TW686X_VIDEO_HEIGHT(id) ((id & V4L2_STD_525_60) ? 480 : 576) +#define TW686X_MAX_FPS(id) ((id & V4L2_STD_525_60) ? 30 : 25) #define TW686X_MAX_SG_ENTRY_SIZE 4096 #define TW686X_MAX_SG_DESC_COUNT 256 /* PAL 720x576 needs 203 4-KB pages */ @@ -340,53 +341,79 @@ static const struct tw686x_dma_ops sg_dma_ops = { .field = V4L2_FIELD_SEQ_TB, }; -static unsigned int tw686x_fields_map(v4l2_std_id std, unsigned int fps) +static const unsigned int fps_map[15] = { + /* + * bit 31 enables selecting the field control register + * bits 0-29 are a bitmask with fields that will be output. + * For NTSC (and PAL-M, PAL-60), all 30 bits are used. + * For other PAL standards, only the first 25 bits are used. + */ + 0x00000000, /* output all fields */ + 0x80000006, /* 2 fps (60Hz), 2 fps (50Hz) */ + 0x80018006, /* 4 fps (60Hz), 4 fps (50Hz) */ + 0x80618006, /* 6 fps (60Hz), 6 fps (50Hz) */ + 0x81818186, /* 8 fps (60Hz), 8 fps (50Hz) */ + 0x86186186, /* 10 fps (60Hz), 8 fps (50Hz) */ + 0x86619866, /* 12 fps (60Hz), 10 fps (50Hz) */ + 0x86666666, /* 14 fps (60Hz), 12 fps (50Hz) */ + 0x9999999e, /* 16 fps (60Hz), 14 fps (50Hz) */ + 0x99e6799e, /* 18 fps (60Hz), 16 fps (50Hz) */ + 0x9e79e79e, /* 20 fps (60Hz), 16 fps (50Hz) */ + 0x9e7e7e7e, /* 22 fps (60Hz), 18 fps (50Hz) */ + 0x9fe7f9fe, /* 24 fps (60Hz), 20 fps (50Hz) */ + 0x9ffe7ffe, /* 26 fps (60Hz), 22 fps (50Hz) */ + 0x9ffffffe, /* 28 fps (60Hz), 24 fps (50Hz) */ +}; + +static unsigned int tw686x_real_fps(unsigned int index, unsigned int max_fps) { - static const unsigned int map[15] = { - 0x00000000, 0x00000001, 0x00004001, 0x00104001, 0x00404041, - 0x01041041, 0x01104411, 0x01111111, 0x04444445, 0x04511445, - 0x05145145, 0x05151515, 0x05515455, 0x05551555, 0x05555555 - }; - - static const unsigned int std_625_50[26] = { - 0, 1, 1, 2, 3, 3, 4, 4, 5, 5, 6, 7, 7, - 8, 8, 9, 10, 10, 11, 11, 12, 13, 13, 14, 14, 0 - }; - - static const unsigned int std_525_60[31] = { - 0, 1, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, - 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 13, 13, 14, 0, 0 - }; + unsigned long mask; - unsigned int i; + if (!index || index >= ARRAY_SIZE(fps_map)) + return max_fps; - if (std & V4L2_STD_525_60) { - if (fps >= ARRAY_SIZE(std_525_60)) - fps = 30; - i = std_525_60[fps]; - } else { - if (fps >= ARRAY_SIZE(std_625_50)) - fps = 25; - i = std_625_50[fps]; - } + mask = GENMASK(max_fps - 1, 0); + return hweight_long(fps_map[index] & mask); +} + +static unsigned int tw686x_fps_idx(unsigned int fps, unsigned int max_fps) +{ + unsigned int idx, real_fps; + int delta; + + /* First guess */ + idx = (12 + 15 * fps) / max_fps; + + /* Minimal possible framerate is 2 frames per second */ + if (!idx) + return 1; + + /* Check if the difference is bigger than abs(1) and adjust */ + real_fps = tw686x_real_fps(idx, max_fps); + delta = real_fps - fps; + if (delta < -1) + idx++; + else if (delta > 1) + idx--; + + /* Max framerate */ + if (idx >= 15) + return 0; - return map[i]; + return idx; } static void tw686x_set_framerate(struct tw686x_video_channel *vc, unsigned int fps) { - unsigned int map; + unsigned int i; if (vc->fps == fps) return; - map = tw686x_fields_map(vc->video_standard, fps) << 1; - map |= map << 1; - if (map > 0) - map |= BIT(31); - reg_write(vc->dev, VIDEO_FIELD_CTRL[vc->ch], map); - vc->fps = fps; + i = tw686x_fps_idx(fps, TW686X_MAX_FPS(vc->video_standard)); + reg_write(vc->dev, VIDEO_FIELD_CTRL[vc->ch], fps_map[i]); + vc->fps = tw686x_real_fps(i, TW686X_MAX_FPS(vc->video_standard)); } static const struct tw686x_format *format_by_fourcc(unsigned int fourcc) -- 2.45.2