iq: Make the IQ parameters configurable

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

1 files changed, 100 insertions, 34 deletions

diff --git a/iq.c b/iq.c
index b02c297..c407b6e 100644
--- a/iq.c
+++ b/iq.c
@@ -37,22 +37,14 @@ struct iq_tuning {
 
 	unsigned int frame_count;
 	unsigned int pix_max;
-	float mean_level;
 
-	unsigned int exposure;
-	unsigned int exposure_min;
-	unsigned int exposure_max;
-
-	unsigned int gain;
-	unsigned int gain_min;
-	unsigned int gain_max;
-
-	unsigned int black_level;
+	struct iq_params params;
 };
 
 void iq_aewb_process(struct iq_tuning *iq,
 		     const struct omap3_isp_aewb_stats *stats)
 {
+	struct iq_params *iqp = &iq->params;
 	unsigned int i;
 	float gains[4];
 	double factor;
@@ -77,24 +69,104 @@ void iq_aewb_process(struct iq_tuning *iq,
 	     + stats->accum[2] + stats->accum[3];
 	mean /= 4 * stats->npix;
 
-	factor = (iq->pix_max * iq->mean_level) / mean;
+	factor = (iq->pix_max * iqp->mean_level) / mean;
 
-	gain = factor * iq->exposure * iq->gain / iq->gain_min;
-	iq->exposure = clamp((unsigned int)gain,
-			    iq->exposure_min, iq->exposure_max);
+	gain = factor * iqp->exposure * iqp->gain / iqp->gain_min;
+	iqp->exposure = clamp((unsigned int)gain,
+			      iqp->exposure_min, iqp->exposure_max);
 
-	gain = gain / iq->exposure * iq->gain_min;
-	iq->gain = clamp((unsigned int)gain,
-			iq->gain_min, iq->gain_max);
+	gain = gain / iqp->exposure * iqp->gain_min;
+	iqp->gain = clamp((unsigned int)gain, iqp->gain_min, iqp->gain_max);
 
 	printf("AE: factor %.4f exposure %u sensor gain %u\n",
-		factor, iq->exposure, iq->gain);
+		factor, iqp->exposure, iqp->gain);
 
-	omap3_isp_sensor_set_exposure(iq->isp, iq->exposure);
-	omap3_isp_sensor_set_gain(iq->isp, iq->gain);
+	omap3_isp_sensor_set_exposure(iq->isp, iqp->exposure);
+	omap3_isp_sensor_set_gain(iq->isp, iqp->gain);
 }
 
-struct iq_tuning *iq_init(struct omap3_isp_device *isp)
+/**
+ * iq_params_init - Initialize IQ parameters
+ * @params: IQ parameters
+ *
+ * Fill the passed params structure with the default IQ parameters.
+ */
+void iq_params_init(struct iq_params *params)
+{
+	params->mean_level = 0.15;
+	params->exposure = 1000;
+	params->exposure_min = 10;
+	params->exposure_max = 2000;
+	params->gain = 8;
+	params->gain_min = 8;
+	params->gain_max = 1024;
+	params->black_level = 64;
+}
+
+/**
+ * iq_params_parse - Parse an IQ parameter string
+ * @params: IQ parameters
+ * @arg: Parameter string
+ *
+ * Parse the given parameter string and store the parameter value in the params
+ * structure. The parameter string must have the form
+ *
+ *	name=value
+ *
+ * Return 0 on success or a negative error code otherwise:
+ *
+ * -EINVAL: The string format or the parameter name is invalid
+ * -ERANGE: The parameter value is out of range for the given parameter
+ */
+int iq_params_parse(struct iq_params *params, const char *arg)
+{
+	unsigned int *val_uint;
+	const char *value;
+	unsigned int size;
+	char *endp;
+
+	value = strchr(arg, '=');
+	if (value == NULL)
+		return -EINVAL;
+
+	size = value - arg;
+	value++;
+
+	if (strncmp(arg, "mean-level", size) == 0) {
+		params->mean_level = strtof(value, &endp);
+		if (*endp != '\0')
+			return -EINVAL;
+
+		if (params->mean_level <= 0 || params-> mean_level >= 1)
+			return -ERANGE;
+
+		return 0;
+	}
+
+	if (strncmp(arg, "exposure-def", size) == 0)
+		val_uint = &params->exposure;
+	else if (strncmp(arg, "exposure-min", size) == 0)
+		val_uint = &params->exposure_min;
+	else if (strncmp(arg, "exposure-max", size) == 0)
+		val_uint = &params->exposure_max;
+	else if (strncmp(arg, "gain-def", size) == 0)
+		val_uint = &params->gain;
+	else if (strncmp(arg, "gain-min", size) == 0)
+		val_uint = &params->gain_min;
+	else if (strncmp(arg, "gain-max", size) == 0)
+		val_uint = &params->gain_max;
+	else
+		return -EINVAL;
+
+	*val_uint = strtoul(value, &endp, 10);
+	if (*endp != '\0')
+		return -EINVAL;
+
+	return 0;
+}
+
+struct iq_tuning *iq_init(struct omap3_isp_device *isp,
+			  const struct iq_params *params)
 {
 	struct v4l2_mbus_framefmt format;
 	struct v4l2_rect window;
@@ -107,18 +179,12 @@ struct iq_tuning *iq_init(struct omap3_isp_device *isp)
 	iq->isp = isp;
 	iq->frame_count = 0;
 	iq->pix_max = (1 << 10) - 1;
-	iq->mean_level = 0.15;
-	iq->exposure = 1000;
-	iq->exposure_min = 10;
-	iq->exposure_max = 2000;
-	iq->gain = 8;
-	iq->gain_min = 8;
-	iq->gain_max = 1024;
-	iq->black_level = 64;
-
-	omap3_isp_sensor_set_gain(isp, iq->gain);
-	omap3_isp_sensor_set_exposure(isp, iq->exposure);
-	omap3_isp_ccdc_set_black_level(isp, iq->black_level);
+
+	iq->params = *params;
+
+	omap3_isp_sensor_set_gain(isp, iq->params.gain);
+	omap3_isp_sensor_set_exposure(isp, iq->params.exposure);
+	omap3_isp_ccdc_set_black_level(isp, iq->params.black_level);
 
 	omap3_isp_stats_get_format(isp, &format);
 	window.left = 0;
@@ -126,7 +192,7 @@ struct iq_tuning *iq_init(struct omap3_isp_device *isp)
 	window.width = format.width;
 	window.height = format.height;
 
-	omap3_isp_aewb_configure(isp, &window, iq->pix_max - iq->black_level - 1);
+	omap3_isp_aewb_configure(isp, &window, iq->pix_max - iq->params.black_level - 1);
 	omap3_isp_stats_enable(isp, true);
 
 	return iq;