From 5fb2dde28122e74bbab9dae3cc04bcbc8c08b332 Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Wed, 17 Feb 2010 11:59:19 -0300 Subject: [PATCH] V4L/DVB: gspca_pac7302: much improved exposure control My experience with fixing up the controls for the PAS sensors in sonixb, has lead me to re-investigate the exposure control for the pac7302. I've now found a regular exposure register in register bank 3 (which seems to be the sensor registers bank), and with this added a proper fine grained exposure control. This patch also updates the do_autogain function to work properly with this new finer grained control. Signed-off-by: Hans de Goede Signed-off-by: Mauro Carvalho Chehab --- drivers/media/video/gspca/pac7302.c | 105 ++++++++++++++++----------------- drivers/media/video/gspca/pac_common.h | 9 ++- 2 files changed, 54 insertions(+), 60 deletions(-) diff --git a/drivers/media/video/gspca/pac7302.c b/drivers/media/video/gspca/pac7302.c index 19f0cd8..2a68220 100644 --- a/drivers/media/video/gspca/pac7302.c +++ b/drivers/media/video/gspca/pac7302.c @@ -24,33 +24,26 @@ */ /* Some documentation about various registers as determined by trial and error. - When the register addresses differ between the 7202 and the 7311 the 2 - different addresses are written as 7302addr/7311addr, when one of the 2 - addresses is a - sign that register description is not valid for the - matching IC. Register page 1: Address Description - -/0x08 Unknown compressor related, must always be 8 except when not - in 640x480 resolution and page 4 reg 2 <= 3 then set it to 9 ! - -/0x1b Auto white balance related, bit 0 is AWB enable (inverted) - bits 345 seem to toggle per color gains on/off (inverted) 0x78 Global control, bit 6 controls the LED (inverted) - -/0x80 JPEG compression ratio ? Best not touched - Register page 3/4: + Register page 3: Address Description - 0x02 Clock divider 2-63, fps =~ 60 / val. Must be a multiple of 3 on + 0x02 Clock divider 3-63, fps = 90 / val. Must be a multiple of 3 on 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) + 0x03 Variable framerate ctrl reg2==3: 0 -> ~30 fps, 255 -> ~22fps + 0x04 Another var framerate ctrl reg2==3, reg3==0: 0 -> ~30 fps, + 63 -> ~27 fps, the 2 msb's must always be 1 !! + 0x05 Another var framerate ctrl reg2==3, reg3==0, reg4==0xc0: + 1 -> ~30 fps, 2 -> ~20 fps + 0x0e Exposure bits 0-7, 0-448, 0 = use full frame time + 0x0f Exposure bit 8, 0-448, 448 = no exposure at all + 0x10 Master gain 0-31 0x21 Bitfield: 0-1 unused, 2-3 vflip/hflip, 4-5 unknown, 6-7 unused - -/0x27 Seems to toggle various gains on / off, Setting bit 7 seems to - completely disable the analog amplification block. Set to 0x68 - for max gain, 0x14 for minimal gain. The registers are accessed in the following functions: @@ -89,8 +82,8 @@ struct sd { unsigned char red_balance; unsigned char blue_balance; unsigned char gain; - unsigned char exposure; unsigned char autogain; + unsigned short exposure; __u8 hflip; __u8 vflip; u8 flags; @@ -128,7 +121,6 @@ static int sd_setexposure(struct gspca_dev *gspca_dev, __s32 val); static int sd_getexposure(struct gspca_dev *gspca_dev, __s32 *val); static const struct ctrl sd_ctrls[] = { -/* This control is pac7302 only */ { { .id = V4L2_CID_BRIGHTNESS, @@ -144,7 +136,6 @@ static const struct ctrl sd_ctrls[] = { .set = sd_setbrightness, .get = sd_getbrightness, }, -/* This control is for both the 7302 and the 7311 */ { { .id = V4L2_CID_CONTRAST, @@ -160,7 +151,6 @@ static const struct ctrl sd_ctrls[] = { .set = sd_setcontrast, .get = sd_getcontrast, }, -/* This control is pac7302 only */ { { .id = V4L2_CID_SATURATION, @@ -218,7 +208,6 @@ static const struct ctrl sd_ctrls[] = { .set = sd_setbluebalance, .get = sd_getbluebalance, }, -/* All controls below are for both the 7302 and the 7311 */ { { .id = V4L2_CID_GAIN, @@ -241,11 +230,10 @@ static const struct ctrl sd_ctrls[] = { .type = V4L2_CTRL_TYPE_INTEGER, .name = "Exposure", .minimum = 0, -#define EXPOSURE_MAX 255 - .maximum = EXPOSURE_MAX, + .maximum = 1023, .step = 1, -#define EXPOSURE_DEF 16 /* 32 ms / 30 fps */ -#define EXPOSURE_KNEE 50 /* 100 ms / 10 fps */ +#define EXPOSURE_DEF 66 /* 33 ms / 30 fps */ +#define EXPOSURE_KNEE 133 /* 66 ms / 15 fps */ .default_value = EXPOSURE_DEF, }, .set = sd_setexposure, @@ -381,7 +369,7 @@ static const __u8 start_7302[] = { #define SKIP 0xaa /* page 3 - the value SKIP says skip the index - see reg_w_page() */ static const __u8 page3_7302[] = { - 0x90, 0x40, 0x03, 0x50, 0xc2, 0x01, 0x14, 0x16, + 0x90, 0x40, 0x03, 0x00, 0xc0, 0x01, 0x14, 0x16, 0x14, 0x12, 0x00, 0x00, 0x00, 0x02, 0x33, 0x00, 0x0f, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x47, 0x01, 0xb3, 0x01, 0x00, @@ -653,23 +641,39 @@ static void setgain(struct gspca_dev *gspca_dev) static void setexposure(struct gspca_dev *gspca_dev) { struct sd *sd = (struct sd *) gspca_dev; - __u8 reg; - - /* register 2 of frame 3/4 contains the clock divider configuring the - no fps according to the formula: 60 / reg. sd->exposure is the - desired exposure time in ms. */ - reg = 120 * sd->exposure / 1000; - if (reg < 2) - reg = 2; - else if (reg > 63) - reg = 63; - - /* On the pac7302 reg2 MUST be a multiple of 3, so round it to - the nearest multiple of 3, except when between 6 and 12? */ - if (reg < 6 || reg > 12) - reg = ((reg + 1) / 3) * 3; + __u8 clockdiv; + __u16 exposure; + + /* register 2 of frame 3 contains the clock divider configuring the + no fps according to the formula: 90 / reg. sd->exposure is the + desired exposure time in 0.5 ms. */ + clockdiv = (90 * sd->exposure + 1999) / 2000; + + /* Note clockdiv = 3 also works, but when running at 30 fps, depending + on the scene being recorded, the camera switches to another + quantization table for certain JPEG blocks, and we don't know how + to decompress these blocks. So we cap the framerate at 15 fps */ + if (clockdiv < 6) + clockdiv = 6; + else if (clockdiv > 63) + clockdiv = 63; + + /* reg2 MUST be a multiple of 3, except when between 6 and 12? + Always round up, otherwise we cannot get the desired frametime + using the partial frame time exposure control */ + if (clockdiv < 6 || clockdiv > 12) + clockdiv = ((clockdiv + 2) / 3) * 3; + + /* frame exposure time in ms = 1000 * clockdiv / 90 -> + exposure = (sd->exposure / 2) * 448 / (1000 * clockdiv / 90) */ + exposure = (sd->exposure * 45 * 448) / (1000 * clockdiv); + /* 0 = use full frametime, 448 = no exposure, reverse it */ + exposure = 448 - exposure; + reg_w(gspca_dev, 0xff, 0x03); /* page 3 */ - reg_w(gspca_dev, 0x02, reg); + reg_w(gspca_dev, 0x02, clockdiv); + reg_w(gspca_dev, 0x0e, exposure & 0xff); + reg_w(gspca_dev, 0x0f, exposure >> 8); /* load registers to sensor (Bit 0, auto clear) */ reg_w(gspca_dev, 0x11, 0x01); @@ -756,22 +760,13 @@ 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, deadzone; + int desired_lum; + const int deadzone = 30; if (avg_lum == -1) return; - 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; + desired_lum = 270 + sd->brightness; if (sd->autogain_ignore_frames > 0) sd->autogain_ignore_frames--; diff --git a/drivers/media/video/gspca/pac_common.h b/drivers/media/video/gspca/pac_common.h index 20f67d9..8462a7c 100644 --- a/drivers/media/video/gspca/pac_common.h +++ b/drivers/media/video/gspca/pac_common.h @@ -24,11 +24,10 @@ */ /* We calculate the autogain at the end of the transfer of a frame, at this - moment a frame with the old settings is being transmitted, and a frame is - being captured with the old settings. So if we adjust the autogain we must - ignore atleast the 2 next frames for the new settings to come into effect - before doing any other adjustments */ -#define PAC_AUTOGAIN_IGNORE_FRAMES 3 + moment a frame with the old settings is being captured and transmitted. So + if we adjust the gain or exposure we must ignore atleast the next frame for + the new settings to come into effect before doing any other adjustments. */ +#define PAC_AUTOGAIN_IGNORE_FRAMES 2 static const unsigned char pac_sof_marker[5] = { 0xff, 0xff, 0x00, 0xff, 0x96 }; -- 2.7.4