diff --git a/Documentation/video4linux/v4l2-framework.txt b/Documentation/video4linux/v4l2-framework.txt
index d54c1e4..ba4706a 100644
--- a/Documentation/video4linux/v4l2-framework.txt
+++ b/Documentation/video4linux/v4l2-framework.txt
@@ -390,6 +390,30 @@
 To see which chip variants are supported you can look in the i2c driver code
 for the i2c_device_id table. This lists all the possibilities.
 
+There are two more helper functions:
+
+v4l2_i2c_new_subdev_cfg: this function adds new irq and platform_data
+arguments and has both 'addr' and 'probed_addrs' arguments: if addr is not
+0 then that will be used (non-probing variant), otherwise the probed_addrs
+are probed.
+
+For example: this will probe for address 0x10:
+
+struct v4l2_subdev *sd = v4l2_i2c_new_subdev_cfg(v4l2_dev, adapter,
+	       "module_foo", "chipid", 0, NULL, 0, I2C_ADDRS(0x10));
+
+v4l2_i2c_new_subdev_board uses an i2c_board_info struct which is passed
+to the i2c driver and replaces the irq, platform_data and addr arguments.
+
+If the subdev supports the s_config core ops, then that op is called with
+the irq and platform_data arguments after the subdev was setup. The older
+v4l2_i2c_new_(probed_)subdev functions will call s_config as well, but with
+irq set to 0 and platform_data set to NULL.
+
+Note that in the next kernel release the functions v4l2_i2c_new_subdev,
+v4l2_i2c_new_probed_subdev and v4l2_i2c_new_probed_subdev_addr will all be
+replaced by a single v4l2_i2c_new_subdev that is identical to
+v4l2_i2c_new_subdev_cfg but without the irq and platform_data arguments.
 
 struct video_device
 -------------------