media: i2c: alvium: enable acquisition frame rate

Alvium camera by default is in free running mode. Datasheet say that
acquisition frame rate reg can only be used if frame start trigger
mode is set to off.
Enable r/w acquisition frame rate and turn off trigger mode.
Signed-off-by: Tommaso Merciai <tomm.merciai@gmail.com>
[Sakari Ailus: Fix spelling of "acquisition".]
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

drivers/media/i2c/alvium-csi2.c

@@ -1189,6 +1189,20 @@ static int alvium_set_frame_rate(struct alvium_dev *alvium, u64 fr)
 	struct device *dev = &alvium->i2c_client->dev;
 	int ret;
 
+	ret = alvium_write_hshake(alvium, REG_BCRM_ACQUISITION_FRAME_RATE_EN_RW,
+				  1);
+	if (ret) {
+		dev_err(dev, "Fail to set acquisition frame rate enable reg\n");
+		return ret;
+	}
+
+	ret = alvium_write_hshake(alvium, REG_BCRM_FRAME_START_TRIGGER_MODE_RW,
+				  0);
+	if (ret) {
+		dev_err(dev, "Fail to set frame start trigger mode reg\n");
+		return ret;
+	}
+
 	ret = alvium_write_hshake(alvium, REG_BCRM_ACQUISITION_FRAME_RATE_RW,
 				  fr);
 	if (ret) {