linux/Documentation/devicetree/bindings/sound/sgtl5000.txt
Alison Wang 5dc4ca2996
ASoC: sgtl5000: Allow SCLK pad drive strength to be changed
This patch introduces "sclk-strength" property to allow SCLK pad drive
strength to be changed via device tree.

When running playback test on LS1028ARDB, Tx Frame sync error interrupt
will occur sometimes. Some noises also exist. After changing SCLK pad
drive strength to the maximum value, the issues are gone.

Signed-off-by: Alison Wang <alison.wang@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2019-01-07 18:11:25 +00:00

61 lines
1.5 KiB
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* Freescale SGTL5000 Stereo Codec
Required properties:
- compatible : "fsl,sgtl5000".
- reg : the I2C address of the device
- #sound-dai-cells: must be equal to 0
- clocks : the clock provider of SYS_MCLK
- VDDA-supply : the regulator provider of VDDA
- VDDIO-supply: the regulator provider of VDDIO
Optional properties:
- VDDD-supply : the regulator provider of VDDD
- micbias-resistor-k-ohms : the bias resistor to be used in kOhms
The resistor can take values of 2k, 4k or 8k.
If set to 0 it will be off.
If this node is not mentioned or if the value is unknown, then
micbias resistor is set to 4K.
- micbias-voltage-m-volts : the bias voltage to be used in mVolts
The voltage can take values from 1.25V to 3V by 250mV steps
If this node is not mentioned or the value is unknown, then
the value is set to 1.25V.
- lrclk-strength: the LRCLK pad strength. Possible values are:
0, 1, 2 and 3 as per the table below:
VDDIO 1.8V 2.5V 3.3V
0 = Disable
1 = 1.66 mA 2.87 mA 4.02 mA
2 = 3.33 mA 5.74 mA 8.03 mA
3 = 4.99 mA 8.61 mA 12.05 mA
- sclk-strength: the SCLK pad strength. Possible values are:
0, 1, 2 and 3 as per the table below:
VDDIO 1.8V 2.5V 3.3V
0 = Disable
1 = 1.66 mA 2.87 mA 4.02 mA
2 = 3.33 mA 5.74 mA 8.03 mA
3 = 4.99 mA 8.61 mA 12.05 mA
Example:
sgtl5000: codec@a {
compatible = "fsl,sgtl5000";
reg = <0x0a>;
#sound-dai-cells = <0>;
clocks = <&clks 150>;
micbias-resistor-k-ohms = <2>;
micbias-voltage-m-volts = <2250>;
VDDA-supply = <&reg_3p3v>;
VDDIO-supply = <&reg_3p3v>;
};