[alsa-devel] [PATCH] audio: sgtl5000: Add MicBias resistor support in DT
Some systems may require a different resistor than the default one (4K). This adds a property in sgtl5000 codec. It keeps the default of 4K when nothing is specified so it does not break existing code.
Signed-off-by: Jean-Michel Hautbois jean-michel.hautbois@vodalys.com --- .../devicetree/bindings/sound/sgtl5000.txt | 10 ++++ sound/soc/codecs/sgtl5000.c | 56 ++++++++++++++++++++-- 2 files changed, 62 insertions(+), 4 deletions(-)
diff --git a/Documentation/devicetree/bindings/sound/sgtl5000.txt b/Documentation/devicetree/bindings/sound/sgtl5000.txt index 955df60..dd38f84 100644 --- a/Documentation/devicetree/bindings/sound/sgtl5000.txt +++ b/Documentation/devicetree/bindings/sound/sgtl5000.txt @@ -7,10 +7,20 @@ Required properties:
- clocks : the clock provider of SYS_MCLK
+- sgtl5000-micbias-resistor : the bias resistor to be used + 1 or SGTL5000_MICBIAS_2K - MICBIAS resistor is set to 2K + 2 or SGTL5000_MICBIAS_4K - MICBIAS resistor is set to 4K + 3 or SGTL5000_MICBIAS_8K - MICBIAS resistor is set to 8K + 0 or SGTL5000_MICBIAS_OFF - MICBIAS resistor is not used + If this node is not mentioned or if the value is unknown, then + micbias resistor is set to 4K. + + Example:
codec: sgtl5000@0a { compatible = "fsl,sgtl5000"; reg = <0x0a>; clocks = <&clks 150>; + sgtl5000-micbias-resistor = <1>; }; diff --git a/sound/soc/codecs/sgtl5000.c b/sound/soc/codecs/sgtl5000.c index 6bb77d7..f538957 100644 --- a/sound/soc/codecs/sgtl5000.c +++ b/sound/soc/codecs/sgtl5000.c @@ -121,6 +121,13 @@ struct ldo_regulator { bool enabled; };
+enum sgtl5000_micbias_resistor { + SGTL5000_MICBIAS_OFF = 0, + SGTL5000_MICBIAS_2K = 1, + SGTL5000_MICBIAS_4K = 2, + SGTL5000_MICBIAS_8K = 3, +}; + /* sgtl5000 private structure in codec */ struct sgtl5000_priv { int sysclk; /* sysclk rate */ @@ -131,6 +138,7 @@ struct sgtl5000_priv { struct regmap *regmap; struct clk *mclk; int revision; + enum sgtl5000_micbias_resistor micbias_resistor; };
/* @@ -145,12 +153,14 @@ struct sgtl5000_priv { static int mic_bias_event(struct snd_soc_dapm_widget *w, struct snd_kcontrol *kcontrol, int event) { + struct sgtl5000_priv *sgtl5000 = snd_soc_codec_get_drvdata(w->codec); + switch (event) { case SND_SOC_DAPM_POST_PMU: - /* change mic bias resistor to 4Kohm */ + /* change mic bias resistor */ snd_soc_update_bits(w->codec, SGTL5000_CHIP_MIC_CTRL, - SGTL5000_BIAS_R_MASK, - SGTL5000_BIAS_R_4k << SGTL5000_BIAS_R_SHIFT); + SGTL5000_BIAS_R_MASK, + sgtl5000->micbias_resistor << SGTL5000_BIAS_R_SHIFT); break;
case SND_SOC_DAPM_PRE_PMD: @@ -1326,7 +1336,16 @@ static int sgtl5000_probe(struct snd_soc_codec *codec) SGTL5000_HP_ZCD_EN | SGTL5000_ADC_ZCD_EN);
- snd_soc_write(codec, SGTL5000_CHIP_MIC_CTRL, 2); + switch (sgtl5000->micbias_resistor) { + case SGTL5000_MICBIAS_2K: + case SGTL5000_MICBIAS_4K: + case SGTL5000_MICBIAS_8K: + snd_soc_update_bits(codec, SGTL5000_CHIP_MIC_CTRL, + SGTL5000_BIAS_R_MASK, + sgtl5000->micbias_resistor << SGTL5000_BIAS_R_SHIFT); + default: + break; + }
/* * disable DAP @@ -1418,6 +1437,8 @@ static int sgtl5000_i2c_probe(struct i2c_client *client, struct sgtl5000_priv *sgtl5000; int ret, reg, rev; unsigned int mclk; + struct device_node *np = client->dev.of_node; + u32 value;
sgtl5000 = devm_kzalloc(&client->dev, sizeof(struct sgtl5000_priv), GFP_KERNEL); @@ -1470,6 +1491,33 @@ static int sgtl5000_i2c_probe(struct i2c_client *client, dev_info(&client->dev, "sgtl5000 revision 0x%x\n", rev); sgtl5000->revision = rev;
+ if (np) { + if (!of_property_read_u32(np, + "sgtl5000-micbias-resistor", &value)) { + switch (value) { + case 1: + sgtl5000->micbias_resistor = + SGTL5000_MICBIAS_2K; + break; + case 2: + sgtl5000->micbias_resistor = + SGTL5000_MICBIAS_4K; + break; + case 3: + sgtl5000->micbias_resistor = + SGTL5000_MICBIAS_8K; + break; + default: + sgtl5000->micbias_resistor = + SGTL5000_MICBIAS_OFF; + dev_err(&client->dev, + "Unsuitable MicBias resistor\n"); + } + } else { + sgtl5000->micbias_resistor = SGTL5000_MICBIAS_4K; + } + } + i2c_set_clientdata(client, sgtl5000);
/* Ensure sgtl5000 will start with sane register values */
On Sun, Oct 12, 2014 at 3:39 PM, Jean-Michel Hautbois jean-michel.hautbois@vodalys.com wrote:
if (np) {
if (!of_property_read_u32(np,
"sgtl5000-micbias-resistor", &value)) {
switch (value) {
case 1:
sgtl5000->micbias_resistor =
SGTL5000_MICBIAS_2K;
break;
case 2:
sgtl5000->micbias_resistor =
SGTL5000_MICBIAS_4K;
break;
case 3:
sgtl5000->micbias_resistor =
SGTL5000_MICBIAS_8K;
break;
default:
sgtl5000->micbias_resistor =
SGTL5000_MICBIAS_OFF;
dev_err(&client->dev,
"Unsuitable MicBias resistor\n");
The case 0 should SGTL5000_MICBIAS_OFF and the default should be SGTL5000_MICBIAS_4K.
Hi Fabio,
2014-10-12 23:15 GMT+02:00 Fabio Estevam festevam@gmail.com:
On Sun, Oct 12, 2014 at 3:39 PM, Jean-Michel Hautbois jean-michel.hautbois@vodalys.com wrote:
if (np) {
if (!of_property_read_u32(np,
"sgtl5000-micbias-resistor", &value)) {
switch (value) {
case 1:
sgtl5000->micbias_resistor =
SGTL5000_MICBIAS_2K;
break;
case 2:
sgtl5000->micbias_resistor =
SGTL5000_MICBIAS_4K;
break;
case 3:
sgtl5000->micbias_resistor =
SGTL5000_MICBIAS_8K;
break;
default:
sgtl5000->micbias_resistor =
SGTL5000_MICBIAS_OFF;
dev_err(&client->dev,
"Unsuitable MicBias resistor\n");
The case 0 should SGTL5000_MICBIAS_OFF and the default should be SGTL5000_MICBIAS_4K.
You are right of course, second version sent. I have a patch wich adds MicBias voltage support too, but it will be on top of this one, is this a problem ?
Thanks, JM
Hi Jean-Michel,
On Sun, Oct 12, 2014 at 6:42 PM, Jean-Michel Hautbois jean-michel.hautbois@vodalys.com wrote:
You are right of course, second version sent. I have a patch wich adds MicBias voltage support too, but it will be on top of this one, is this a problem ?
In this case you could send a series of two patches: PATCH v3 1/2 and PATCH v3 2/2
2014-10-13 0:39 GMT+02:00 Fabio Estevam festevam@gmail.com:
Hi Jean-Michel,
On Sun, Oct 12, 2014 at 6:42 PM, Jean-Michel Hautbois jean-michel.hautbois@vodalys.com wrote:
You are right of course, second version sent. I have a patch wich adds MicBias voltage support too, but it will be on top of this one, is this a problem ?
In this case you could send a series of two patches: PATCH v3 1/2 and PATCH v3 2/2
I am using a "big" enum of 8 values, but there may be a nicer way to do it. In the datasheet it is said that MICBIAS_VOLT is set in 250mV steps, from 1.25V when register is 0 to 3.00V when register is 7.
Thanks, JM
participants (2)
-
Fabio Estevam
-
Jean-Michel Hautbois