isp: Emulate global gain for sensors that only expose color gains

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

1 files changed, 70 insertions, 0 deletions

diff --git a/isp/controls.c b/isp/controls.c
index cce4265..05ab20b 100644
--- a/isp/controls.c
+++ b/isp/controls.c
@@ -343,6 +343,70 @@ int omap3_isp_preview_setup(struct omap3_isp_device *isp)
 #define V4L2_CID_GAIN_GREEN2		(V4L2_CTRL_CLASS_CAMERA | 0x1003)
 #define V4L2_CID_GAIN_BLUE		(V4L2_CTRL_CLASS_CAMERA | 0x1004)
 
+#define SENSOR_GAIN_GLOBAL		(1 << 0)
+#define SENSOR_GAIN_RED			(1 << 1)
+#define SENSOR_GAIN_GREEN1		(1 << 2)
+#define SENSOR_GAIN_GREEN2		(1 << 3)
+#define SENSOR_GAIN_BLUE		(1 << 4)
+#define SENSOR_GAIN_COLORS		(SENSOR_GAIN_RED | \
+					 SENSOR_GAIN_GREEN1 | \
+					 SENSOR_GAIN_GREEN2 | \
+					 SENSOR_GAIN_BLUE)
+
+int omap3_isp_sensor_init(struct omap3_isp_device *isp)
+{
+	struct v4l2_queryctrl query;
+	unsigned int gains = 0;
+	__u32 id;
+	int ret;
+
+	/* Retrieve the sensor default format. */
+	ret = v4l2_subdev_get_format(isp->sensor.entity, &isp->sensor.format, 0,
+				     V4L2_SUBDEV_FORMAT_TRY);
+	if (ret < 0) {
+		printf("error: unable to get sensor default format.\n");
+		return ret;
+	}
+
+	for (id = 0; ; id = query.id) {
+		memset(&query, 0, sizeof query);
+		query.id = id | V4L2_CTRL_FLAG_NEXT_CTRL;
+		ret = ioctl(isp->sensor.entity->fd, VIDIOC_QUERYCTRL, &query);
+		if (ret < 0) {
+			if (errno == EINVAL)
+				break;
+
+			printf("error: unable to get sensor default format.\n");
+			return -errno;
+		}
+
+		switch (query.id) {
+		case V4L2_CID_GAIN:
+			gains |= SENSOR_GAIN_GLOBAL;
+			break;
+		case V4L2_CID_GAIN_RED:
+			gains |= SENSOR_GAIN_RED;
+			break;
+		case V4L2_CID_GAIN_GREEN1:
+			gains |= SENSOR_GAIN_GREEN1;
+			break;
+		case V4L2_CID_GAIN_GREEN2:
+			gains |= SENSOR_GAIN_GREEN2;
+			break;
+		case V4L2_CID_GAIN_BLUE:
+			gains |= SENSOR_GAIN_BLUE;
+			break;
+		}
+	}
+
+	if ((gains & SENSOR_GAIN_COLORS) == SENSOR_GAIN_COLORS)
+		isp->sensor.has_color_gains = true;
+	if (gains & SENSOR_GAIN_GLOBAL)
+		isp->sensor.has_global_gain = true;
+
+	return 0;
+}
+
 int omap3_isp_sensor_get_exposure(struct omap3_isp_device *isp,
 				  unsigned int *exposure)
 {
@@ -374,6 +438,9 @@ int omap3_isp_sensor_set_gain(struct omap3_isp_device *isp, unsigned int gain)
 {
 	struct v4l2_ext_control ctrls[1];
 
+	if (!isp->sensor.has_global_gain)
+		return omap3_isp_sensor_set_gains(isp, gain, gain, gain);
+
 	ctrls[0].id = V4L2_CID_GAIN;
 	ctrls[0].value = gain;
 
@@ -386,6 +453,9 @@ int omap3_isp_sensor_set_gains(struct omap3_isp_device *isp,
 	struct v4l2_ext_control ctrls[4];
 	unsigned int i = 0;
 
+	if (!isp->sensor.has_color_gains)
+		return -EINVAL;
+
 	if (red != OMAP3_ISP_SENSOR_GAIN_KEEP) {
 		ctrls[i].id = V4L2_CID_GAIN_RED;
 		ctrls[i++].value = red;