[PATCH 1/3] gspca_zc3xx: Implement proper autogain and exposure control for OV7648

[Ondrej Zary]

The ZS0211 internal autogain causes pumping and flickering with OV7648
sensor on 0ac8:307b webcam.
Implement OV7648 autogain and exposure control and use that instead.

Signed-off-by: Ondrej Zary <li...@rainbow-software.org>
---
 drivers/media/usb/gspca/zc3xx.c | 42 +++++++++++++++++++++++++++++++++--------
 1 file changed, 34 insertions(+), 8 deletions(-)

diff --git a/drivers/media/usb/gspca/zc3xx.c b/drivers/media/usb/gspca/zc3xx.c
index 25b4dbe8e049..992918b3ad0c 100644
--- a/drivers/media/usb/gspca/zc3xx.c
+++ b/drivers/media/usb/gspca/zc3xx.c
@@ -5778,16 +5778,34 @@ static void setcontrast(struct gspca_dev *gspca_dev,
 
 static s32 getexposure(struct gspca_dev *gspca_dev)
 {
-       return (i2c_read(gspca_dev, 0x25) << 9)
-               | (i2c_read(gspca_dev, 0x26) << 1)
-               | (i2c_read(gspca_dev, 0x27) >> 7);
+       struct sd *sd = (struct sd *) gspca_dev;
+
+       switch (sd->sensor) {
+       case SENSOR_HV7131R:
+               return (i2c_read(gspca_dev, 0x25) << 9)
+                       | (i2c_read(gspca_dev, 0x26) << 1)
+                       | (i2c_read(gspca_dev, 0x27) >> 7);
+       case SENSOR_OV7620:
+               return i2c_read(gspca_dev, 0x10);
+       default:
+               return -1;
+       }
 }
 
 static void setexposure(struct gspca_dev *gspca_dev, s32 val)
 {
-       i2c_write(gspca_dev, 0x25, val >> 9, 0x00);
-       i2c_write(gspca_dev, 0x26, val >> 1, 0x00);
-       i2c_write(gspca_dev, 0x27, val << 7, 0x00);
+       struct sd *sd = (struct sd *) gspca_dev;
+
+       switch (sd->sensor) {
+       case SENSOR_HV7131R:
+               i2c_write(gspca_dev, 0x25, val >> 9, 0x00);
+               i2c_write(gspca_dev, 0x26, val >> 1, 0x00);
+               i2c_write(gspca_dev, 0x27, val << 7, 0x00);
+               break;
+       case SENSOR_OV7620:
+               i2c_write(gspca_dev, 0x10, val, 0x00);
+               break;
+       }
 }
 
 static void setquality(struct gspca_dev *gspca_dev)
@@ -5918,7 +5936,12 @@ static void setlightfreq(struct gspca_dev *gspca_dev, 
s32 val)
 
 static void setautogain(struct gspca_dev *gspca_dev, s32 val)
 {
-       reg_w(gspca_dev, val ? 0x42 : 0x02, 0x0180);
+       struct sd *sd = (struct sd *) gspca_dev;
+
+       if (sd->sensor == SENSOR_OV7620)
+               i2c_write(gspca_dev, 0x13, val ? 0xa3 : 0x80, 0x00);
+       else
+               reg_w(gspca_dev, val ? 0x42 : 0x02, 0x0180);
 }
 
 /*
@@ -6439,6 +6462,9 @@ static int sd_init_controls(struct gspca_dev *gspca_dev)
        if (sd->sensor == SENSOR_HV7131R)
                sd->exposure = v4l2_ctrl_new_std(hdl, &zcxx_ctrl_ops,
                        V4L2_CID_EXPOSURE, 0x30d, 0x493e, 1, 0x927);
+       else if (sd->sensor == SENSOR_OV7620)
+               sd->exposure = v4l2_ctrl_new_std(hdl, &zcxx_ctrl_ops,
+                       V4L2_CID_EXPOSURE, 0, 255, 1, 0x41);
        sd->autogain = v4l2_ctrl_new_std(hdl, &zcxx_ctrl_ops,
                        V4L2_CID_AUTOGAIN, 0, 1, 1, 1);
        if (sd->sensor != SENSOR_OV7630C)
@@ -6458,7 +6484,7 @@ static int sd_init_controls(struct gspca_dev *gspca_dev)
                return hdl->error;
        }
        v4l2_ctrl_cluster(3, &sd->gamma);
-       if (sd->sensor == SENSOR_HV7131R)
+       if (sd->sensor == SENSOR_HV7131R || sd->sensor == SENSOR_OV7620)
                v4l2_ctrl_auto_cluster(2, &sd->autogain, 0, true);
        return 0;
 }
-- 
Ondrej Zary