V4L/DVB (8348): gspca: Add auto gain/exposure to sonixb and tas5110 / ov6650 sensors.

sonixb:   Do auto gain for tas5110 / ov6650 sensors.
pac207:   Move the auto_gain function to gspca.
gspca:    New function gspca_auto_gain_n_exposure().

Signed-off-by: Hans de Goede <j.w.r.degoede@hhs.nl>
Signed-off-by: Jean-Francois Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

4 files changed, 350 insertions, 109 deletions

diff --git a/drivers/media/video/gspca/gspca.c b/drivers/media/video/gspca/gspca.c
index 09f190c689d5..2ffb00ab0811 100644
--- a/drivers/media/video/gspca/gspca.c
+++ b/drivers/media/video/gspca/gspca.c
@@ -1790,6 +1790,94 @@ void gspca_disconnect(struct usb_interface *intf)
 }
 EXPORT_SYMBOL(gspca_disconnect);
 
+/* -- cam driver utility functions -- */
+
+/* auto gain and exposure algorithm based on the knee algorithm described here:
+   http://ytse.tricolour.net/docs/LowLightOptimization.html
+
+   Returns 0 if no changes were made, 1 if the gain and or exposure settings
+   where changed. */
+int gspca_auto_gain_n_exposure(struct gspca_dev *gspca_dev, int avg_lum,
+        int desired_avg_lum, int deadzone, int gain_knee, int exposure_knee)
+{
+        int i, steps, gain, orig_gain, exposure, orig_exposure, autogain;
+        const struct ctrl *gain_ctrl = NULL;
+        const struct ctrl *exposure_ctrl = NULL;
+        const struct ctrl *autogain_ctrl = NULL;
+        int retval = 0;
+
+        for (i = 0; i < gspca_dev->sd_desc->nctrls; i++) {
+                if (gspca_dev->sd_desc->ctrls[i].qctrl.id == V4L2_CID_GAIN)
+                        gain_ctrl = &gspca_dev->sd_desc->ctrls[i];
+                if (gspca_dev->sd_desc->ctrls[i].qctrl.id == V4L2_CID_EXPOSURE)
+                        exposure_ctrl = &gspca_dev->sd_desc->ctrls[i];
+                if (gspca_dev->sd_desc->ctrls[i].qctrl.id == V4L2_CID_AUTOGAIN)
+                        autogain_ctrl = &gspca_dev->sd_desc->ctrls[i];
+        }
+        if (!gain_ctrl || !exposure_ctrl || !autogain_ctrl) {
+                PDEBUG(D_ERR, "Error: gspca_auto_gain_n_exposure called "
+                        "on cam without (auto)gain/exposure");
+                return 0;
+        }
+
+        if (gain_ctrl->get(gspca_dev, &gain) ||
+                        exposure_ctrl->get(gspca_dev, &exposure) ||
+                        autogain_ctrl->get(gspca_dev, &autogain) || !autogain)
+                return 0;
+
+        orig_gain = gain;
+        orig_exposure = exposure;
+
+        /* If we are of a multiple of deadzone, do multiple steps to reach the
+           desired lumination fast (with the risc of a slight overshoot) */
+        steps = abs(desired_avg_lum - avg_lum) / deadzone;
+
+        PDEBUG(D_FRAM, "autogain: lum: %d, desired: %d, steps: %d\n",
+                avg_lum, desired_avg_lum, steps);
+
+        for (i = 0; i < steps; i++) {
+                if (avg_lum > desired_avg_lum) {
+                        if (gain > gain_knee)
+                                gain--;
+                        else if (exposure > exposure_knee)
+                                exposure--;
+                        else if (gain > gain_ctrl->qctrl.default_value)
+                                gain--;
+                        else if (exposure > exposure_ctrl->qctrl.minimum)
+                                exposure--;
+                        else if (gain > gain_ctrl->qctrl.minimum)
+                                gain--;
+                        else
+                                break;
+                } else {
+                        if (gain < gain_ctrl->qctrl.default_value)
+                                gain++;
+                        else if (exposure < exposure_knee)
+                                exposure++;
+                        else if (gain < gain_knee)
+                                gain++;
+                        else if (exposure < exposure_ctrl->qctrl.maximum)
+                                exposure++;
+                        else if (gain < gain_ctrl->qctrl.maximum)
+                                gain++;
+                        else
+                                break;
+                }
+        }
+
+        if (gain != orig_gain) {
+                gain_ctrl->set(gspca_dev, gain);
+                retval = 1;
+        }
+        if (exposure != orig_exposure) {
+                exposure_ctrl->set(gspca_dev, exposure);
+                retval = 1;
+        }
+
+        return retval;
+}
+EXPORT_SYMBOL(gspca_auto_gain_n_exposure);
+
 /* -- module insert / remove -- */
 static int __init gspca_init(void)
 {
diff --git a/drivers/media/video/gspca/gspca.h b/drivers/media/video/gspca/gspca.h
index 9b645af81a07..78fccefcd576 100644
--- a/drivers/media/video/gspca/gspca.h
+++ b/drivers/media/video/gspca/gspca.h
@@ -170,4 +170,6 @@ struct gspca_frame *gspca_frame_add(struct gspca_dev *gspca_dev,
                                     struct gspca_frame *frame,
                                     const __u8 *data,
                                     int len);
+int gspca_auto_gain_n_exposure(struct gspca_dev *gspca_dev, int avg_lum,
+        int desired_avg_lum, int deadzone, int gain_knee, int exposure_knee);
 #endif /* GSPCAV2_H */
diff --git a/drivers/media/video/gspca/pac207.c b/drivers/media/video/gspca/pac207.c
index 4f197c1f4a76..5d68d3f42262 100644
--- a/drivers/media/video/gspca/pac207.c
+++ b/drivers/media/video/gspca/pac207.c
@@ -357,70 +357,20 @@ static void sd_close(struct gspca_dev *gspca_dev)
 {
 }
 
-/* auto gain and exposure algorithm based on the knee algorithm described here:
- * <http://ytse.tricolour.net/docs/LowLightOptimization.html> */
 static void pac207_do_auto_gain(struct gspca_dev *gspca_dev)
 {
         struct sd *sd = (struct sd *) gspca_dev;
-        int i, steps, desired_avg_lum;
-        int orig_gain = sd->gain;
-        int orig_exposure = sd->exposure;
         int avg_lum = atomic_read(&sd->avg_lum);
 
-        if (!sd->autogain || avg_lum == -1)
+        if (avg_lum == -1)
                 return;
 
-        if (sd->autogain_ignore_frames > 0) {
+        if (sd->autogain_ignore_frames > 0)
                 sd->autogain_ignore_frames--;
-                return;
-        }
-
-        /* correct desired lumination for the configured brightness */
-        desired_avg_lum = 100 + sd->brightness / 2;
-
-        /* If we are of a multiple of deadzone, do multiple step to reach the
-           desired lumination fast (with the risc of a slight overshoot) */
-        steps = abs(desired_avg_lum - avg_lum) / PAC207_AUTOGAIN_DEADZONE;
-
-        for (i = 0; i < steps; i++) {
-                if (avg_lum > desired_avg_lum) {
-                        if (sd->gain > PAC207_GAIN_KNEE)
-                                sd->gain--;
-                        else if (sd->exposure > PAC207_EXPOSURE_KNEE)
-                                sd->exposure--;
-                        else if (sd->gain > PAC207_GAIN_DEFAULT)
-                                sd->gain--;
-                        else if (sd->exposure > PAC207_EXPOSURE_MIN)
-                                sd->exposure--;
-                        else if (sd->gain > PAC207_GAIN_MIN)
-                                sd->gain--;
-                        else
-                                break;
-                } else {
-                        if (sd->gain < PAC207_GAIN_DEFAULT)
-                                sd->gain++;
-                        else if (sd->exposure < PAC207_EXPOSURE_KNEE)
-                                sd->exposure++;
-                        else if (sd->gain < PAC207_GAIN_KNEE)
-                                sd->gain++;
-                        else if (sd->exposure < PAC207_EXPOSURE_MAX)
-                                sd->exposure++;
-                        else if (sd->gain < PAC207_GAIN_MAX)
-                                sd->gain++;
-                        else
-                                break;
-                }
-        }
-
-        if (sd->exposure != orig_exposure || sd->gain != orig_gain) {
-                if (sd->exposure != orig_exposure)
-                        pac207_write_reg(gspca_dev, 0x0002, sd->exposure);
-                if (sd->gain != orig_gain)
-                        pac207_write_reg(gspca_dev, 0x000e, sd->gain);
-                pac207_write_reg(gspca_dev, 0x13, 0x01); /* load reg to sen */
-                pac207_write_reg(gspca_dev, 0x1c, 0x01); /* not documented */
+        else if (gspca_auto_gain_n_exposure(gspca_dev, avg_lum,
+                        100 + sd->brightness / 2, PAC207_AUTOGAIN_DEADZONE,
+                        PAC207_GAIN_KNEE, PAC207_EXPOSURE_KNEE))
                 sd->autogain_ignore_frames = PAC207_AUTOGAIN_IGNORE_FRAMES;
-        }
 }
 
 static unsigned char *pac207_find_sof(struct gspca_dev *gspca_dev,
@@ -546,10 +496,6 @@ static int sd_setexposure(struct gspca_dev *gspca_dev, __s32 val)
 {
         struct sd *sd = (struct sd *) gspca_dev;
 
-        /* don't allow mucking with exposure when using autogain */
-        if (sd->autogain)
-                return -EINVAL;
-
         sd->exposure = val;
         if (gspca_dev->streaming)
                 setexposure(gspca_dev);
@@ -568,10 +514,6 @@ static int sd_setgain(struct gspca_dev *gspca_dev, __s32 val)
 {
         struct sd *sd = (struct sd *) gspca_dev;
 
-        /* don't allow mucking with gain when using autogain */
-        if (sd->autogain)
-                return -EINVAL;
-
         sd->gain = val;
         if (gspca_dev->streaming)
                 setgain(gspca_dev);
diff --git a/drivers/media/video/gspca/sonixb.c b/drivers/media/video/gspca/sonixb.c
index 95a6a8e98b97..274df69e6f6d 100644
--- a/drivers/media/video/gspca/sonixb.c
+++ b/drivers/media/video/gspca/sonixb.c
@@ -35,11 +35,19 @@ MODULE_LICENSE("GPL");
 struct sd {
         struct gspca_dev gspca_dev;     /* !! must be the first item */
 
+        struct sd_desc sd_desc;         /* our nctrls differ dependend upon the
+                                           sensor, so we use a per cam copy */
+        atomic_t avg_lum;
+
+        unsigned short gain;
+        unsigned short exposure;
         unsigned char brightness;
-        unsigned char contrast;
+        unsigned char autogain;
+        unsigned char autogain_ignore_frames;
 
         unsigned char fr_h_sz;          /* size of frame header */
         char sensor;                    /* Type of image sensor chip */
+        char sensor_has_gain;
 #define SENSOR_HV7131R 0
 #define SENSOR_OV6650 1
 #define SENSOR_OV7630 2
@@ -59,11 +67,24 @@ struct sd {
 
 #define SYS_CLK 0x04
 
+/* 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 AUTOGAIN_IGNORE_FRAMES 3
+#define AUTOGAIN_DEADZONE 500
+#define DESIRED_AVG_LUM 7000
+
 /* V4L2 controls supported by the driver */
 static int sd_setbrightness(struct gspca_dev *gspca_dev, __s32 val);
 static int sd_getbrightness(struct gspca_dev *gspca_dev, __s32 *val);
-static int sd_setcontrast(struct gspca_dev *gspca_dev, __s32 val);
-static int sd_getcontrast(struct gspca_dev *gspca_dev, __s32 *val);
+static int sd_setgain(struct gspca_dev *gspca_dev, __s32 val);
+static int sd_getgain(struct gspca_dev *gspca_dev, __s32 *val);
+static int sd_setexposure(struct gspca_dev *gspca_dev, __s32 val);
+static int sd_getexposure(struct gspca_dev *gspca_dev, __s32 *val);
+static int sd_setautogain(struct gspca_dev *gspca_dev, __s32 val);
+static int sd_getautogain(struct gspca_dev *gspca_dev, __s32 *val);
 
 static struct ctrl sd_ctrls[] = {
 #define SD_BRIGHTNESS 0
@@ -75,24 +96,59 @@ static struct ctrl sd_ctrls[] = {
                 .minimum = 0,
                 .maximum = 255,
                 .step    = 1,
-                .default_value = 127,
+#define BRIGHTNESS_DEF 127
+                .default_value = BRIGHTNESS_DEF,
             },
             .set = sd_setbrightness,
             .get = sd_getbrightness,
         },
-#define SD_CONTRAST 1
+#define SD_GAIN 1
         {
             {
-                .id      = V4L2_CID_CONTRAST,
+                .id      = V4L2_CID_GAIN,
                 .type    = V4L2_CTRL_TYPE_INTEGER,
-                .name    = "Contrast",
+                .name    = "Gain",
                 .minimum = 0,
-                .maximum = 255,
+                .maximum = 511,
                 .step    = 1,
-                .default_value = 127,
+#define GAIN_DEF 255
+#define GAIN_KNEE 400
+                .default_value = GAIN_DEF,
             },
-            .set = sd_setcontrast,
-            .get = sd_getcontrast,
+            .set = sd_setgain,
+            .get = sd_getgain,
+        },
+#define SD_EXPOSURE 2
+        {
+                {
+                        .id = V4L2_CID_EXPOSURE,
+                        .type = V4L2_CTRL_TYPE_INTEGER,
+                        .name = "Exposure",
+#define EXPOSURE_DEF 0
+#define EXPOSURE_KNEE 353 /* 10 fps */
+                        .minimum = 0,
+                        .maximum = 511,
+                        .step = 1,
+                        .default_value = EXPOSURE_DEF,
+                        .flags = 0,
+                },
+                .set = sd_setexposure,
+                .get = sd_getexposure,
+        },
+#define SD_AUTOGAIN 3
+        {
+                {
+                        .id = V4L2_CID_AUTOGAIN,
+                        .type = V4L2_CTRL_TYPE_BOOLEAN,
+                        .name = "Automatic Gain (and Exposure)",
+                        .minimum = 0,
+                        .maximum = 1,
+                        .step = 1,
+                        .default_value = 1,
+                        .flags = 0,
+                },
+                .set = sd_setautogain,
+                .get = sd_getautogain,
         },
 };
 
@@ -153,8 +209,12 @@ static const __u8 ov6650_sensor_init[][8] =
         /* Bright, contrast, etc are set througth SCBB interface.
          * AVCAP on win2 do not send any data on this   controls. */
         /* Anyway, some registers appears to alter bright and constrat */
+
+        /* Reset sensor */
         {0xa0, 0x60, 0x12, 0x80, 0x00, 0x00, 0x00, 0x10},
+        /* Set clock register 0x11 low nibble is clock divider */
         {0xd0, 0x60, 0x11, 0xc0, 0x1b, 0x18, 0xc1, 0x10},
+        /* Next some unknown stuff */
         {0xb0, 0x60, 0x15, 0x00, 0x02, 0x18, 0xc1, 0x10},
 /*      {0xa0, 0x60, 0x1b, 0x01, 0x02, 0x18, 0xc1, 0x10},
                  * THIS SET GREEN SCREEN
@@ -163,31 +223,18 @@ static const __u8 ov6650_sensor_init[][8] =
         {0xd0, 0x60, 0x26, 0x01, 0x14, 0xd8, 0xa4, 0x10}, /* format out? */
         {0xd0, 0x60, 0x26, 0x01, 0x14, 0xd8, 0xa4, 0x10},
         {0xa0, 0x60, 0x30, 0x3d, 0x0A, 0xd8, 0xa4, 0x10},
+        /* Disable autobright ? */
         {0xb0, 0x60, 0x60, 0x66, 0x68, 0xd8, 0xa4, 0x10},
+        /* Some more unknown stuff */
         {0xa0, 0x60, 0x68, 0x04, 0x68, 0xd8, 0xa4, 0x10},
         {0xd0, 0x60, 0x17, 0x24, 0xd6, 0x04, 0x94, 0x10}, /* Clipreg */
-        {0xa0, 0x60, 0x10, 0x5d, 0x99, 0x04, 0x94, 0x16},
-        {0xa0, 0x60, 0x2d, 0x0a, 0x99, 0x04, 0x94, 0x16},
-        {0xa0, 0x60, 0x32, 0x00, 0x99, 0x04, 0x94, 0x16},
-        {0xa0, 0x60, 0x33, 0x40, 0x99, 0x04, 0x94, 0x16},
-        {0xa0, 0x60, 0x11, 0xc0, 0x99, 0x04, 0x94, 0x16},
-        {0xa0, 0x60, 0x00, 0x16, 0x99, 0x04, 0x94, 0x15}, /* bright / Lumino */
-        {0xa0, 0x60, 0x2b, 0xab, 0x99, 0x04, 0x94, 0x15},
-                                                        /* ?flicker o brillo */
-        {0xa0, 0x60, 0x2d, 0x2a, 0x99, 0x04, 0x94, 0x15},
-        {0xa0, 0x60, 0x2d, 0x2b, 0x99, 0x04, 0x94, 0x16},
-        {0xa0, 0x60, 0x32, 0x00, 0x99, 0x04, 0x94, 0x16},
-        {0xa0, 0x60, 0x33, 0x00, 0x99, 0x04, 0x94, 0x16},
         {0xa0, 0x60, 0x10, 0x57, 0x99, 0x04, 0x94, 0x16},
-        {0xa0, 0x60, 0x2d, 0x2b, 0x99, 0x04, 0x94, 0x16},
-        {0xa0, 0x60, 0x32, 0x00, 0x99, 0x04, 0x94, 0x16},
-                /* Low Light (Enabled: 0x32 0x1 | Disabled: 0x32 0x00) */
-        {0xa0, 0x60, 0x33, 0x29, 0x99, 0x04, 0x94, 0x16},
-                /* Low Ligth (Enabled: 0x33 0x13 | Disabled: 0x33 0x29) */
-/*      {0xa0, 0x60, 0x11, 0xc1, 0x99, 0x04, 0x94, 0x16}, */
-        {0xa0, 0x60, 0x00, 0x17, 0x99, 0x04, 0x94, 0x15}, /* clip? r */
-        {0xa0, 0x60, 0x00, 0x18, 0x99, 0x04, 0x94, 0x15}, /* clip? r */
+        /* Framerate adjust register for artificial light 50 hz flicker
+           compensation, identical to ov6630 0x2b register, see 6630 datasheet.
+           0x4f -> (30 fps -> 25 fps), 0x00 -> no adjustment */
+        {0xa0, 0x60, 0x2b, 0x4f, 0x99, 0x04, 0x94, 0x15},
 };
+
 static const __u8 initOv7630[] = {
         0x04, 0x44, 0x00, 0x00, 0x00, 0x00, 0x00, 0x80, /* r01 .. r08 */
         0x21, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* r09 .. r10 */
@@ -469,8 +516,7 @@ static void setbrightness(struct gspca_dev *gspca_dev)
                         goto err;
                 break;
             }
-        case SENSOR_TAS5130CXX:
-        case SENSOR_TAS5110: {
+        case SENSOR_TAS5130CXX: {
                 __u8 i2c[] =
                         {0x30, 0x11, 0x02, 0x20, 0x70, 0x00, 0x00, 0x10};
 
@@ -481,24 +527,112 @@ static void setbrightness(struct gspca_dev *gspca_dev)
                         goto err;
                 break;
             }
+        case SENSOR_TAS5110:
+                /* FIXME figure out howto control brightness on TAS5110 */
+                break;
         }
         return;
 err:
         PDEBUG(D_ERR, "i2c error brightness");
 }
-static void setcontrast(struct gspca_dev *gspca_dev)
+
+static void setsensorgain(struct gspca_dev *gspca_dev)
+{
+        struct sd *sd = (struct sd *) gspca_dev;
+        unsigned short gain;
+
+        gain = (sd->gain + 1) >> 1;
+        if (gain > 255)
+                gain = 255;
+
+        switch (sd->sensor) {
+
+        case SENSOR_TAS5110: {
+                __u8 i2c[] =
+                        {0x30, 0x11, 0x02, 0x20, 0x70, 0x00, 0x00, 0x10};
+
+                i2c[4] = 255 - gain;
+                if (i2c_w(gspca_dev->dev, i2c) < 0)
+                        goto err;
+                break; }
+
+        case SENSOR_OV6650: {
+                __u8 i2c[] = {0xa0, 0x60, 0x00, 0x00, 0x00, 0x00, 0x00, 0x10};
+                i2c[3] = gain;
+                if (i2c_w(gspca_dev->dev, i2c) < 0)
+                        goto err;
+                break; }
+        }
+        return;
+err:
+        PDEBUG(D_ERR, "i2c error gain");
+}
+
+static void setgain(struct gspca_dev *gspca_dev)
 {
         struct sd *sd = (struct sd *) gspca_dev;
         __u8 gain;
         __u8 rgb_value;
 
-        gain = sd->contrast >> 4;
+        gain = sd->gain >> 5;
+
         /* red and blue gain */
         rgb_value = gain << 4 | gain;
         reg_w(gspca_dev->dev, 0x10, &rgb_value, 1);
         /* green gain */
         rgb_value = gain;
         reg_w(gspca_dev->dev, 0x11, &rgb_value, 1);
+
+        if (sd->sensor_has_gain)
+                setsensorgain(gspca_dev);
+}
+
+static void setexposure(struct gspca_dev *gspca_dev)
+{
+        struct sd *sd = (struct sd *) gspca_dev;
+        /* translate 0 - 255 to a number of fps in a 30 - 1 scale */
+        int fps = 30 - sd->exposure * 29 / 511;
+
+        switch (sd->sensor) {
+        case SENSOR_TAS5110: {
+                __u8 reg;
+
+                /* register 19's high nibble contains the sn9c10x clock divider
+                   The high nibble configures the no fps according to the
+                   formula: 60 / high_nibble. With a maximum of 30 fps */
+                reg = 60 / fps;
+                if (reg > 15)
+                        reg = 15;
+                reg = (reg << 4) | 0x0b;
+                reg_w(gspca_dev->dev, 0x19, &reg, 1);
+                break; }
+        case SENSOR_OV6650: {
+                __u8 i2c[] = {0xa0, 0x60, 0x11, 0xc0, 0x00, 0x00, 0x00, 0x10};
+                i2c[3] = 30 / fps - 1;
+                if (i2c[3] > 15)
+                        i2c[3] = 15;
+                i2c[3] |= 0xc0;
+                if (i2c_w(gspca_dev->dev, i2c) < 0)
+                        PDEBUG(D_ERR, "i2c error exposure");
+                break; }
+        }
+}
+
+
+static void do_autogain(struct gspca_dev *gspca_dev)
+{
+        struct sd *sd = (struct sd *) gspca_dev;
+        int avg_lum = atomic_read(&sd->avg_lum);
+
+        if (avg_lum == -1)
+                return;
+
+        if (sd->autogain_ignore_frames > 0)
+                sd->autogain_ignore_frames--;
+        else if (gspca_auto_gain_n_exposure(gspca_dev, avg_lum,
+                        sd->brightness * DESIRED_AVG_LUM / 127,
+                        AUTOGAIN_DEADZONE, GAIN_KNEE, EXPOSURE_KNEE))
+                sd->autogain_ignore_frames = AUTOGAIN_IGNORE_FRAMES;
 }
 
 /* this function is called at probe time */
@@ -511,7 +645,13 @@ static int sd_config(struct gspca_dev *gspca_dev,
         __u16 product;
         int sif = 0;
 
+        /* nctrls depends upon the sensor, so we use a per cam copy */
+        memcpy(&sd->sd_desc, gspca_dev->sd_desc, sizeof(struct sd_desc));
+        gspca_dev->sd_desc = &sd->sd_desc;
+
         sd->fr_h_sz = 12;               /* default size of the frame header */
+        sd->sd_desc.nctrls = 2;         /* default no ctrls */
+
 /*      vendor = id->idVendor; */
         product = id->idProduct;
 /*      switch (vendor) { */
@@ -521,6 +661,9 @@ static int sd_config(struct gspca_dev *gspca_dev,
                 case 0x6005:                    /* SN9C101 */
                 case 0x6007:                    /* SN9C101 */
                         sd->sensor = SENSOR_TAS5110;
+                        sd->sensor_has_gain = 1;
+                        sd->sd_desc.nctrls = 4;
+                        sd->sd_desc.dq_callback = do_autogain;
                         sif = 1;
                         break;
                 case 0x6009:                    /* SN9C101 */
@@ -531,6 +674,9 @@ static int sd_config(struct gspca_dev *gspca_dev,
                         break;
                 case 0x6011:                    /* SN9C101 - SN9C101G */
                         sd->sensor = SENSOR_OV6650;
+                        sd->sensor_has_gain = 1;
+                        sd->sd_desc.nctrls = 4;
+                        sd->sd_desc.dq_callback = do_autogain;
                         sif = 1;
                         break;
                 case 0x6019:                    /* SN9C101 */
@@ -570,8 +716,10 @@ static int sd_config(struct gspca_dev *gspca_dev,
                 cam->cam_mode = sif_mode;
                 cam->nmodes = sizeof sif_mode / sizeof sif_mode[0];
         }
-        sd->brightness = sd_ctrls[SD_BRIGHTNESS].qctrl.default_value;
-        sd->contrast = sd_ctrls[SD_CONTRAST].qctrl.default_value;
+        sd->brightness = BRIGHTNESS_DEF;
+        sd->gain = GAIN_DEF;
+        sd->exposure = EXPOSURE_DEF;
+        sd->autogain = 1;
         if (sd->sensor == SENSOR_OV7630_3)      /* jfm: from win trace */
                 reg_w(gspca_dev->dev, 0x01, probe_ov7630, sizeof probe_ov7630);
         return 0;
@@ -754,8 +902,12 @@ static void sd_start(struct gspca_dev *gspca_dev)
         reg_w(dev, 0x18, &reg17_19[1], 2);
         msleep(20);
 
-        setcontrast(gspca_dev);
+        setgain(gspca_dev);
         setbrightness(gspca_dev);
+        setexposure(gspca_dev);
+
+        sd->autogain_ignore_frames = 0;
+        atomic_set(&sd->avg_lum, -1);
 }
 
 static void sd_stopN(struct gspca_dev *gspca_dev)
@@ -779,8 +931,8 @@ static void sd_pkt_scan(struct gspca_dev *gspca_dev,
                         unsigned char *data,            /* isoc packet */
                         int len)                        /* iso packet length */
 {
-        struct sd *sd;
         int i;
+        struct sd *sd = (struct sd *) gspca_dev;
 
         if (len > 6 && len < 24) {
                 for (i = 0; i < len - 6; i++) {
@@ -792,7 +944,16 @@ static void sd_pkt_scan(struct gspca_dev *gspca_dev,
                             && data[5 + i] == 0x96) {   /* start of frame */
                                 frame = gspca_frame_add(gspca_dev, LAST_PACKET,
                                                         frame, data, 0);
-                                sd = (struct sd *) gspca_dev;
+                                if (i < (len - 10)) {
+                                        atomic_set(&sd->avg_lum, data[i + 8] +
+                                                        (data[i + 9] << 8));
+                                } else {
+                                        atomic_set(&sd->avg_lum, -1);
+#ifdef CONFIG_VIDEO_ADV_DEBUG
+                                        PDEBUG(D_STREAM, "packet too short to "
+                                                "get avg brightness");
+#endif
+                                }
                                 data += i + sd->fr_h_sz;
                                 len -= i + sd->fr_h_sz;
                                 gspca_frame_add(gspca_dev, FIRST_PACKET,
@@ -823,26 +984,74 @@ static int sd_getbrightness(struct gspca_dev *gspca_dev, __s32 *val)
         return 0;
 }
 
-static int sd_setcontrast(struct gspca_dev *gspca_dev, __s32 val)
+static int sd_setgain(struct gspca_dev *gspca_dev, __s32 val)
+{
+        struct sd *sd = (struct sd *) gspca_dev;
+
+        sd->gain = val;
+        if (gspca_dev->streaming)
+                setgain(gspca_dev);
+        return 0;
+}
+
+static int sd_getgain(struct gspca_dev *gspca_dev, __s32 *val)
 {
         struct sd *sd = (struct sd *) gspca_dev;
 
-        sd->contrast = val;
+        *val = sd->gain;
+        return 0;
+}
+
+static int sd_setexposure(struct gspca_dev *gspca_dev, __s32 val)
+{
+        struct sd *sd = (struct sd *) gspca_dev;
+
+        sd->exposure = val;
         if (gspca_dev->streaming)
-                setcontrast(gspca_dev);
+                setexposure(gspca_dev);
+        return 0;
+}
+
+static int sd_getexposure(struct gspca_dev *gspca_dev, __s32 *val)
+{
+        struct sd *sd = (struct sd *) gspca_dev;
+
+        *val = sd->exposure;
+        return 0;
+}
+
+static int sd_setautogain(struct gspca_dev *gspca_dev, __s32 val)
+{
+        struct sd *sd = (struct sd *) gspca_dev;
+
+        sd->autogain = val;
+        /* when switching to autogain set defaults to make sure
+           we are on a valid point of the autogain gain /
+           exposure knee graph, and give this change time to
+           take effect before doing autogain. */
+        if (sd->autogain) {
+                sd->exposure = EXPOSURE_DEF;
+                sd->gain = GAIN_DEF;
+                if (gspca_dev->streaming) {
+                        sd->autogain_ignore_frames = AUTOGAIN_IGNORE_FRAMES;
+                        setexposure(gspca_dev);
+                        setgain(gspca_dev);
+                }
+        }
+
         return 0;
 }
 
-static int sd_getcontrast(struct gspca_dev *gspca_dev, __s32 *val)
+static int sd_getautogain(struct gspca_dev *gspca_dev, __s32 *val)
 {
         struct sd *sd = (struct sd *) gspca_dev;
 
-        *val = sd->contrast;
+        *val = sd->autogain;
         return 0;
 }
 
 /* sub-driver description */
-static struct sd_desc sd_desc = {
+static const struct sd_desc sd_desc = {
         .name = MODULE_NAME,
         .ctrls = sd_ctrls,
         .nctrls = ARRAY_SIZE(sd_ctrls),