diff --git a/Documentation/ABI/testing/sysfs-bus-iio b/Documentation/ABI/testing/sysfs-bus-iio
index 2210042a11b9a56c15b169dfc2bca9e107427196..587300b388a842efc8a8143e74d49f3da76a8aea 100644
--- a/Documentation/ABI/testing/sysfs-bus-iio
+++ b/Documentation/ABI/testing/sysfs-bus-iio
@@ -665,6 +665,25 @@ Description:
 		Output frequency for channel Y in Hz. The number must always be
 		specified and unique if the output corresponds to a single
 		channel.
+		Some drivers have additional constraints:
+		ADF4371 has an integrated VCO with fundamendal output
+		frequency ranging from 4000000000 Hz 8000000000 Hz.
+
+		out_altvoltage0_frequency:
+			A divide by 1, 2, 4, 8, 16, 32 or circuit generates
+			frequencies from 62500000 Hz to 8000000000 Hz.
+		out_altvoltage1_frequency:
+			This channel duplicates the channel 0 frequency
+		out_altvoltage2_frequency:
+			A frequency doubler generates frequencies from
+			8000000000 Hz to 16000000000 Hz.
+		out_altvoltage3_frequency:
+			A frequency quadrupler generates frequencies from
+			16000000000 Hz to 32000000000 Hz.
+
+		Note: writes to one of the channels will affect the frequency of
+		all the other channels, since it involves changing the VCO
+		fundamental output frequency.
 
 What:		/sys/bus/iio/devices/iio:deviceX/out_altvoltageY_phase
 KernelVersion:	3.4.0
diff --git a/Documentation/ABI/testing/sysfs-bus-iio-frequency-adf4371 b/Documentation/ABI/testing/sysfs-bus-iio-frequency-adf4371
index 457f7590396325faacaeaf56a943a78d36f9bb3a..7fe6935d14487206cbb1908cffaa6ab1d59442cc 100644
--- a/Documentation/ABI/testing/sysfs-bus-iio-frequency-adf4371
+++ b/Documentation/ABI/testing/sysfs-bus-iio-frequency-adf4371
@@ -1,28 +1,3 @@
-What:		/sys/bus/iio/devices/iio:deviceX/out_altvoltageY_frequency
-KernelVersion:
-Contact:	linux-iio@vger.kernel.org
-Description:
-		Stores the PLL frequency in Hz for channel Y.
-		Reading returns the actual frequency in Hz.
-		The ADF4371 has an integrated VCO with fundamendal output
-		frequency ranging from 4000000000 Hz 8000000000 Hz.
-
-		out_altvoltage0_frequency:
-			A divide by 1, 2, 4, 8, 16, 32 or circuit generates
-			frequencies from 62500000 Hz to 8000000000 Hz.
-		out_altvoltage1_frequency:
-			This channel duplicates the channel 0 frequency
-		out_altvoltage2_frequency:
-			A frequency doubler generates frequencies from
-			8000000000 Hz to 16000000000 Hz.
-		out_altvoltage3_frequency:
-			A frequency quadrupler generates frequencies from
-			16000000000 Hz to 32000000000 Hz.
-
-		Note: writes to one of the channels will affect the frequency of
-		all the other channels, since it involves changing the VCO
-		fundamental output frequency.
-
 What:		/sys/bus/iio/devices/iio:deviceX/out_altvoltageY_name
 KernelVersion:
 Contact:	linux-iio@vger.kernel.org