diff --git a/drivers/media/i2c/os04a10.c b/drivers/media/i2c/os04a10.c
index a2923aa2d624..5cd5dd9ad2dd 100644
--- a/drivers/media/i2c/os04a10.c
+++ b/drivers/media/i2c/os04a10.c
@@ -9,6 +9,7 @@
  * V0.0X01.0X02 add debug interface for conversion gain switch.
  * V0.0X01.0X03 support enum sensor fmt
  * V0.0X01.0X04 add quick stream on/off
+ * V0.0X01.0X05 support get dcg ratio from sensor
  */
 
 #include <linux/clk.h>
@@ -31,7 +32,7 @@
 #include <linux/rk-preisp.h>
 #include "../platform/rockchip/isp/rkisp_tb_helper.h"
 
-#define DRIVER_VERSION			KERNEL_VERSION(0, 0x01, 0x04)
+#define DRIVER_VERSION			KERNEL_VERSION(0, 0x01, 0x05)
 
 #ifndef V4L2_CID_DIGITAL_GAIN
 #define V4L2_CID_DIGITAL_GAIN		V4L2_CID_GAIN
@@ -190,6 +191,7 @@ struct os04a10 {
 	bool			is_thunderboot_ng;
 	bool			is_first_streamoff;
 	u8			flip;
+	u32			dcg_ratio;
 };
 
 #define to_os04a10(sd) container_of(sd, struct os04a10, subdev)
@@ -1223,6 +1225,10 @@ static int os04a10_set_hdrae(struct os04a10 *os04a10,
 	if (!os04a10->has_init_exp && !os04a10->streaming) {
 		os04a10->init_hdrae_exp = *ae;
 		os04a10->has_init_exp = true;
+		if (os04a10->init_hdrae_exp.short_exp_reg >= 0x90) {
+			dev_err(&os04a10->client->dev, "short exposure must less than 0x90 before start stream!\n");
+			return -EINVAL;
+		}
 		dev_dbg(&os04a10->client->dev, "os04a10 don't stream, record exp for hdr!\n");
 		return ret;
 	}
@@ -1445,6 +1451,7 @@ static long os04a10_ioctl(struct v4l2_subdev *sd, unsigned int cmd, void *arg)
 {
 	struct os04a10 *os04a10 = to_os04a10(sd);
 	struct rkmodule_hdr_cfg *hdr_cfg;
+	struct rkmodule_dcg_ratio *dcg;
 	long ret = 0;
 	u32 i, h, w;
 	u32 stream = 0;
@@ -1503,6 +1510,17 @@ static long os04a10_ioctl(struct v4l2_subdev *sd, unsigned int cmd, void *arg)
 			ret = os04a10_write_reg(os04a10->client, OS04A10_REG_CTRL_MODE,
 				OS04A10_REG_VALUE_08BIT, OS04A10_MODE_SW_STANDBY);
 		break;
+	case RKMODULE_GET_DCG_RATIO:
+		if (os04a10->dcg_ratio == 0)
+			return -EINVAL;
+		dcg = (struct rkmodule_dcg_ratio *)arg;
+		dcg->integer = (os04a10->dcg_ratio >> 8) & 0xff;
+		dcg->decimal = os04a10->dcg_ratio & 0xff;
+		dcg->div_coeff = 256;
+		dev_info(&os04a10->client->dev,
+			 "get dcg ratio integer %d, decimal %d div_coeff %d\n",
+			 dcg->integer, dcg->decimal, dcg->div_coeff);
+		break;
 	default:
 		ret = -ENOIOCTLCMD;
 		break;
@@ -1520,6 +1538,7 @@ static long os04a10_compat_ioctl32(struct v4l2_subdev *sd,
 	struct rkmodule_awb_cfg *cfg;
 	struct rkmodule_hdr_cfg *hdr;
 	struct preisp_hdrae_exp_s *hdrae;
+	struct rkmodule_dcg_ratio *dcg;
 	long ret;
 	u32 cg = 0;
 	u32 stream = 0;
@@ -1595,6 +1614,18 @@ static long os04a10_compat_ioctl32(struct v4l2_subdev *sd,
 		if (!ret)
 			ret = os04a10_ioctl(sd, cmd, &stream);
 		break;
+	case RKMODULE_GET_DCG_RATIO:
+		dcg = kzalloc(sizeof(*dcg), GFP_KERNEL);
+		if (!dcg) {
+			ret = -ENOMEM;
+			return ret;
+		}
+
+		ret = os04a10_ioctl(sd, cmd, dcg);
+		if (!ret)
+			ret = copy_to_user(up, dcg, sizeof(*dcg));
+		kfree(dcg);
+		break;
 	default:
 		ret = -ENOIOCTLCMD;
 		break;
@@ -2184,6 +2215,36 @@ static int os04a10_configure_regulators(struct os04a10 *os04a10)
 				       os04a10->supplies);
 }
 
+static int os04a10_get_dcg_ratio(struct os04a10 *os04a10)
+{
+	struct device *dev = &os04a10->client->dev;
+	u32 val = 0;
+	int ret = 0;
+
+	if (os04a10->is_thunderboot) {
+		ret = os04a10_read_reg(os04a10->client, 0x77fe,
+					OS04A10_REG_VALUE_16BIT, &val);
+	} else {
+		ret = os04a10_write_reg(os04a10->client, OS04A10_REG_CTRL_MODE,
+					OS04A10_REG_VALUE_08BIT, OS04A10_MODE_STREAMING);
+		usleep_range(5000, 6000);
+		ret |= os04a10_read_reg(os04a10->client, 0x77fe,
+					OS04A10_REG_VALUE_16BIT, &val);
+		ret |= os04a10_write_reg(os04a10->client, OS04A10_REG_CTRL_MODE,
+					OS04A10_REG_VALUE_08BIT, OS04A10_MODE_SW_STANDBY);
+	}
+
+	if (ret != 0 || val == 0) {
+		os04a10->dcg_ratio = 0;
+		dev_err(dev, "get dcg ratio fail, ret %d, dcg ratio %d\n", ret, val);
+	} else {
+		os04a10->dcg_ratio = val;
+		dev_info(dev, "get dcg ratio reg val 0x%04x\n", val);
+	}
+
+	return ret;
+}
+
 static int os04a10_probe(struct i2c_client *client,
 			const struct i2c_device_id *id)
 {
@@ -2285,6 +2346,7 @@ static int os04a10_probe(struct i2c_client *client,
 	ret = os04a10_check_sensor_id(os04a10, client);
 	if (ret)
 		goto err_power_off;
+	ret = os04a10_get_dcg_ratio(os04a10);
 
 #ifdef CONFIG_VIDEO_V4L2_SUBDEV_API
 	sd->internal_ops = &os04a10_internal_ops;
diff --git a/include/uapi/linux/rk-camera-module.h b/include/uapi/linux/rk-camera-module.h
index 14b8dce4d94e..526eb75f3652 100644
--- a/include/uapi/linux/rk-camera-module.h
+++ b/include/uapi/linux/rk-camera-module.h
@@ -96,6 +96,10 @@
 
 #define RKMODULE_GET_BT656_MBUS_INFO	\
 	_IOR('V', BASE_VIDIOC_PRIVATE + 17, struct rkmodule_bt656_mbus_info)
+
+#define RKMODULE_GET_DCG_RATIO	\
+	_IOR('V', BASE_VIDIOC_PRIVATE + 18, struct rkmodule_dcg_ratio)
+
 /**
  * struct rkmodule_base_inf - module base information
  *
@@ -419,5 +423,11 @@ struct rkmodule_bt656_mbus_info {
 	__u32 id_en_bits;
 } __attribute__ ((packed));
 
+/* DCG ratio (float) = integer + decimal / div_coeff */
+struct rkmodule_dcg_ratio {
+	u32 integer;
+	u32 decimal;
+	u32 div_coeff;
+};
 
 #endif /* _UAPI_RKMODULE_CAMERA_H */