From 038ec7c772cb093411b163c22f389787722cfd8e Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Wed, 3 Sep 2008 17:12:18 -0300 Subject: [PATCH] V4L/DVB (8827): gspca: Stop pac7302 autogain oscillation. Signed-off-by: Hans de Goede Signed-off-by: Jean-Francois Moine Signed-off-by: Mauro Carvalho Chehab --- drivers/media/video/gspca/pac7311.c | 48 ++++++++++++++++++++++--------------- 1 file changed, 29 insertions(+), 19 deletions(-) diff --git a/drivers/media/video/gspca/pac7311.c b/drivers/media/video/gspca/pac7311.c index 35244cf..723219d 100644 --- a/drivers/media/video/gspca/pac7311.c +++ b/drivers/media/video/gspca/pac7311.c @@ -39,7 +39,7 @@ Address Description 0x02 Clock divider 2-63, fps =~ 60 / val. Must be a multiple of 3 on - the 7302, so one of 3, 6, 9, ... + the 7302, so one of 3, 6, 9, ..., except when between 6 and 12? -/0x0f Master gain 1-245, low value = high gain 0x10/- Master gain 0-31 -/0x10 Another gain 0-15, limited influence (1-2x gain I guess) @@ -626,8 +626,9 @@ static void setexposure(struct gspca_dev *gspca_dev) if (sd->sensor == SENSOR_PAC7302) { /* On the pac7302 reg2 MUST be a multiple of 3, so round it to - the nearest multiple of 3 */ - reg = ((reg + 1) / 3) * 3; + the nearest multiple of 3, except when between 6 and 12? */ + if (reg < 6 || reg > 12) + reg = ((reg + 1) / 3) * 3; reg_w(gspca_dev, 0xff, 0x03); /* page 3 */ reg_w(gspca_dev, 0x02, reg); } else { @@ -761,20 +762,32 @@ static void do_autogain(struct gspca_dev *gspca_dev) { struct sd *sd = (struct sd *) gspca_dev; int avg_lum = atomic_read(&sd->avg_lum); - int desired_lum; + int desired_lum, deadzone; if (avg_lum == -1) return; - if (sd->sensor == SENSOR_PAC7302) - desired_lum = 70 + sd->brightness * 2; - else + if (sd->sensor == SENSOR_PAC7302) { + desired_lum = 270 + sd->brightness * 4; + /* Hack hack, with the 7202 the first exposure step is + pretty large, so if we're about to make the first + exposure increase make the deadzone large to avoid + oscilating */ + if (desired_lum > avg_lum && sd->gain == GAIN_DEF && + sd->exposure > EXPOSURE_DEF && + sd->exposure < 42) + deadzone = 90; + else + deadzone = 30; + } else { desired_lum = 200; + deadzone = 20; + } if (sd->autogain_ignore_frames > 0) sd->autogain_ignore_frames--; else if (gspca_auto_gain_n_exposure(gspca_dev, avg_lum, desired_lum, - 10, GAIN_KNEE, EXPOSURE_KNEE)) + deadzone, GAIN_KNEE, EXPOSURE_KNEE)) sd->autogain_ignore_frames = PAC_AUTOGAIN_IGNORE_FRAMES; } @@ -802,7 +815,11 @@ static void sd_pkt_scan(struct gspca_dev *gspca_dev, int n, lum_offset, footer_length; if (sd->sensor == SENSOR_PAC7302) { - lum_offset = 34 + sizeof pac_sof_marker; + /* 6 bytes after the FF D9 EOF marker a number of lumination + bytes are send corresponding to different parts of the + image, the 14th and 15th byte after the EOF seem to + correspond to the center of the image */ + lum_offset = 61 + sizeof pac_sof_marker; footer_length = 74; } else { lum_offset = 24 + sizeof pac_sof_marker; @@ -829,18 +846,11 @@ static void sd_pkt_scan(struct gspca_dev *gspca_dev, /* Get average lumination */ if (gspca_dev->last_packet_type == LAST_PACKET && - n >= lum_offset) { - if (sd->sensor == SENSOR_PAC7302) - atomic_set(&sd->avg_lum, - (data[-lum_offset] << 8) | - data[-lum_offset + 1]); - else - atomic_set(&sd->avg_lum, - data[-lum_offset] + + n >= lum_offset) + atomic_set(&sd->avg_lum, data[-lum_offset] + data[-lum_offset + 1]); - } else { + else atomic_set(&sd->avg_lum, -1); - } /* Start the new frame with the jpeg header */ gspca_frame_add(gspca_dev, FIRST_PACKET, frame, -- 2.7.4