@@ -13,6 +13,10 @@ Required properties:
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 mentionned or the value is unknown, then
+ the value is set to 1.25V.
Example:
@@ -20,5 +24,6 @@ codec: sgtl5000@0a {
compatible = "fsl,sgtl5000";
reg = <0x0a>;
clocks = <&clks 150>;
- sgtl5000-micbias-resistor = <1>;
+ micbias-resistor-k-ohms = <2>;
+ micbias-voltage-m-volts = <2250>;
};
@@ -140,6 +140,7 @@ struct sgtl5000_priv {
struct clk *mclk;
int revision;
u8 micbias_resistor;
+ u8 micbias_voltage;
};
/*
@@ -1341,6 +1342,9 @@ static int sgtl5000_probe(struct snd_soc_codec *codec)
SGTL5000_BIAS_R_MASK,
sgtl5000->micbias_resistor << SGTL5000_BIAS_R_SHIFT);
+ snd_soc_update_bits(codec, SGTL5000_CHIP_MIC_CTRL,
+ SGTL5000_BIAS_R_MASK,
+ sgtl5000->micbias_voltage << SGTL5000_BIAS_R_SHIFT);
/*
* disable DAP
* TODO:
@@ -1510,10 +1514,19 @@ static int sgtl5000_i2c_probe(struct i2c_client *client,
/* default is 4Kohms */
sgtl5000->micbias_resistor = 2;
}
+ if (!of_property_read_u32(np,
+ "micbias-voltage-m-volts", &value)) {
+ /* 1250mV => 0 */
+ /* steps of 250mV */
+ if ((value >= 1250) && (value <= 3000))
+ sgtl5000->micbias_voltage = (value / 250) - 5;
+ else {
+ sgtl5000->micbias_voltage = 0;
dev_err(&client->dev,
"Unsuitable MicBias resistor\n");
}
} else {
+ sgtl5000->micbias_voltage = 0;
}
}
Some systems may require to specify a bias different than default (1.25V). This adds a property in sgtl5000 codec. The property is specified in milli-volts so that it is coherent with datasheet. Signed-off-by: Jean-Michel Hautbois <jean-michel.hautbois@vodalys.com> --- Documentation/devicetree/bindings/sound/sgtl5000.txt | 7 ++++++- sound/soc/codecs/sgtl5000.c | 13 +++++++++++++ 2 files changed, 19 insertions(+), 1 deletion(-)