Hi Brian,
On Wednesday 13 of November 2013 09:44:34 Brian Austin wrote:
Add Device Tree Binding for the CS42L52 Codec
v2 Adds clearer explaination of mic configs and select. Renames bindings to '-' instead of '_'. Definition of GPIO for reset pin.
Signed-off-by: Brian Austin brian.austin@cirrus.com
.../devicetree/bindings/sound/cs42l52.txt | 48 ++++++++++++++++++++++ 1 file changed, 48 insertions(+) create mode 100644 Documentation/devicetree/bindings/sound/cs42l52.txt
diff --git a/Documentation/devicetree/bindings/sound/cs42l52.txt b/Documentation/devicetree/bindings/sound/cs42l52.txt new file mode 100644 index 0000000..bd91ecf --- /dev/null +++ b/Documentation/devicetree/bindings/sound/cs42l52.txt @@ -0,0 +1,48 @@ +CS42L52 audio CODEC
+Required properties:
- compatible : "cirrus,cs42l52"
- reg : the I2C address of the device for I2C
+Optional properties:
- reset-gpio : GPIO controller's phandle and the number
of the GPIO used to reset the codec.
As Kumar has already mentioned, all device-specific properties should be prefixed with vendor prefix, "cirrus," in this case.
- chgfreq : Charge Pump Frequency values. Allowable values of
0x00 through 0x0F.Frequency = (64xFs)/(N+2)
I suppose N means the value of chgfreq property here, but this should be clearly stated. Same for Fs - I suppose it is sampling frequency, but is it default, minimum, maximum or maybe something else?
Personally I don't like this kind of raw values being passed using Device Tree, but this one can't be really represented reasonably in a generic way (such as in Hz units) without too much effort to calculate original value in the driver, then it's fine.
- mica-cfg : MIC A single-ended or differential select.
0x00 = Single-Ended0x01 = Differential
I'd rather make it boolean and call it cirrus,mic-a-differential.
- micb-cfg : MIC B single-ended or differential select.
0x00 = Single-Ended0x01 = Differential
Ditto.
- mica-sel : MIC A single ended input select. For Single-Ended
configuration, select which MIC to use.0x00 = MIC10x01 = MIC2
- micb-sel : MIC B single ended input select. For Single-Ended
configuration, select which MIC to use.0x00 = MIC10x01 = MIC2
Could you explain what are MIC A, MIC B, MIC1 and MIC2?
- micbias-lvl: Set the output voltage level on the MICBIAS Pin
0x00 = 0.5 x VA0x01 = 0.6 x VA0x02 = 0.7 x VA0x03 = 0.8 x VA0x04 = 0.83 x VA0x05 = 0.91 x VA
For such small range of values, decimal representation is preferred from readability reasons.
+Example:
+codec: cs42l52@4a {
coding style: Node name should be generic, i.e. codec@4a.
Best regards, Tomasz