Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek...

[sfrench/cifs-2.6.git] / Documentation / devicetree / bindings / sound / rt5663.txt

diff --git a/Documentation/devicetree/bindings/sound/rt5663.txt b/Documentation/devicetree/bindings/sound/rt5663.txt
index ff381718c51755b5d3cb06ac7c0e3ae1a1c85f48..497bcfc58b712173b05ce876600f1595a3d20125 100644 (file)
--- a/Documentation/devicetree/bindings/sound/rt5663.txt
+++ b/Documentation/devicetree/bindings/sound/rt5663.txt
@@ -19,6 +19,22 @@ Optional properties:
   Based on the different PCB layout, add the manual offset value to
   compensate the DC offset for each L and R channel, and they are different
   between headphone and headset.
+- "realtek,impedance_sensing_num"
+  The matrix row number of the impedance sensing table.
+  If the value is 0, it means the impedance sensing is not supported.
+- "realtek,impedance_sensing_table"
+  The matrix rows of the impedance sensing table are consisted by impedance
+  minimum, impedance maximun, volume, DC offset w/o and w/ mic of each L and
+  R channel accordingly. Example is shown as following.
+  <   0    300  7  0xffd160  0xffd1c0  0xff8a10  0xff8ab0
+    301  65535  4  0xffe470  0xffe470  0xffb8e0  0xffb8e0>
+  The first and second column are defined for the impedance range. If the
+  detected impedance value is in the range, then the volume value of the
+  third column will be set to codec. In our codec design, each volume value
+  should compensate different DC offset to avoid the pop sound, and it is
+  also different between headphone and headset. In the example, the
+  "realtek,impedance_sensing_num" is 2. It means that there are 2 ranges of
+  impedance in the impedance sensing function.
 
 Pins on the device (for linking into audio routes) for RT5663: