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>

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)
 {

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 */

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);

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),