diff options
| -rw-r--r-- | drivers/media/video/gspca/pac7311.c | 30 |
1 files changed, 25 insertions, 5 deletions
diff --git a/drivers/media/video/gspca/pac7311.c b/drivers/media/video/gspca/pac7311.c index 54b4ab68f0b..5ccf0b41ffc 100644 --- a/drivers/media/video/gspca/pac7311.c +++ b/drivers/media/video/gspca/pac7311.c @@ -29,7 +29,18 @@ * 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 + * 0x80 Compression balance, interesting settings: + * 0x01 Use this to allow the camera to switch to higher compr. + * on the fly. Needed to stay within bandwidth @ 640x480@30 + * 0x1c From usb captures under Windows for 640x480 + * 0x2a Values >= this switch the camera to a lower compression, + * using the same table for both luminance and chrominance. + * This gives a sharper picture. Usable only at 640x480@ < + * 15 fps or 320x240 / 160x120. Note currently the driver + * does not use this as the quality gain is small and the + * generated JPG-s are only understood by v4l-utils >= 0.8.9 + * 0x3f From usb captures under Windows for 320x240 + * 0x69 From usb captures under Windows for 160x120 * * Register page 4: * @@ -408,12 +419,21 @@ static void setexposure(struct gspca_dev *gspca_dev) * 640x480 mode and page 4 reg 2 <= 3 then it must be 9 */ reg_w(gspca_dev, 0xff, 0x01); - if (gspca_dev->cam.cam_mode[(int)gspca_dev->curr_mode].priv && - sd->ctrls[EXPOSURE].val <= 3) { + if (gspca_dev->width != 640 && sd->ctrls[EXPOSURE].val <= 3) reg_w(gspca_dev, 0x08, 0x09); - } else { + else reg_w(gspca_dev, 0x08, 0x08); - } + + /* + * Page1 register 80 sets the compression balance, normally we + * want / use 0x1c, but for 640x480@30fps we must allow the + * camera to use higher compression or we may run out of + * bandwidth. + */ + if (gspca_dev->width == 640 && sd->ctrls[EXPOSURE].val == 2) + reg_w(gspca_dev, 0x80, 0x01); + else + reg_w(gspca_dev, 0x80, 0x1c); /* load registers to sensor (Bit 0, auto clear) */ reg_w(gspca_dev, 0x11, 0x01); |