Add programmable biquad filter configuration control for user space.
The filter is configurable for low pass filters, high pass filters,
Notch filter, etc in the ADC and DAC path.
Signed-off-by: John Hsu <KCHSU0@xxxxxxxxxxx>
---
sound/soc/codecs/nau8825.c | 53 ++++++++++++++++++++++++++++++++++++++++++++++
sound/soc/codecs/nau8825.h | 8 +++++++
2 files changed, 61 insertions(+)
diff --git a/sound/soc/codecs/nau8825.c b/sound/soc/codecs/nau8825.c
index e988f89..88e01f9 100644
--- a/sound/soc/codecs/nau8825.c
+++ b/sound/soc/codecs/nau8825.c
@@ -217,6 +217,7 @@ static bool nau8825_volatile_reg(struct device *dev, unsigned int reg)
case NAU8825_REG_SARDOUT_RAM_STATUS:
case NAU8825_REG_CHARGE_PUMP_INPUT_READ:
case NAU8825_REG_GENERAL_STATUS:
+ case NAU8825_REG_BIQ_CTRL ... NAU8825_REG_BIQ_COF10:
return true;
default:
return false;
@@ -293,6 +294,54 @@ static int nau8825_output_dac_event(struct snd_soc_dapm_widget *w,
return 0;
}
+static int nau8825_biq_coeff_get(struct snd_kcontrol *kcontrol,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_soc_component *component = snd_kcontrol_chip(kcontrol);
+ struct soc_bytes_ext *params = (void *)kcontrol->private_value;
+
+ if (!component->regmap)
+ return -EINVAL;
+
+ regmap_raw_read(component->regmap, NAU8825_REG_BIQ_COF1,
+ ucontrol->value.bytes.data, params->max);
+ return 0;
+}
+
+static int nau8825_biq_coeff_put(struct snd_kcontrol *kcontrol,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_soc_component *component = snd_kcontrol_chip(kcontrol);
+ struct soc_bytes_ext *params = (void *)kcontrol->private_value;
+ void *data;
+
+ if (!component->regmap)
+ return -EINVAL;
+
+ data = kmemdup(ucontrol->value.bytes.data,
+ params->max, GFP_KERNEL | GFP_DMA);
+ if (!data)
+ return -ENOMEM;
+
+ regmap_update_bits(component->regmap, NAU8825_REG_BIQ_CTRL,
+ NAU8825_BIQ_WRT_EN, 0);
+ regmap_raw_write(component->regmap, NAU8825_REG_BIQ_COF1,
+ data, params->max);
+ regmap_update_bits(component->regmap, NAU8825_REG_BIQ_CTRL,
+ NAU8825_BIQ_WRT_EN, NAU8825_BIQ_WRT_EN);
+
+ kfree(data);
+ return 0;
+}
+
+static const char * const nau8825_biq_path[] = {
+ "ADC", "DAC"
+};
+
+static const struct soc_enum nau8825_biq_path_enum =
+ SOC_ENUM_SINGLE(NAU8825_REG_BIQ_CTRL, NAU8825_BIQ_PATH_SFT,
+ ARRAY_SIZE(nau8825_biq_path), nau8825_biq_path);
+
static const char * const nau8825_adc_decimation[] = {
"32", "64", "128", "256"
};
@@ -329,6 +378,10 @@ static const struct snd_kcontrol_new nau8825_controls[] = {
SOC_ENUM("ADC Decimation Rate", nau8825_adc_decimation_enum),
SOC_ENUM("DAC Oversampling Rate", nau8825_dac_oversampl_enum),
+ /* programmable biquad filter */
+ SOC_ENUM("BIQ Path Select", nau8825_biq_path_enum),
+ SND_SOC_BYTES_EXT("BIQ Coefficeints", 20,
+ nau8825_biq_coeff_get, nau8825_biq_coeff_put),
};
/* DAC Mux 0x33[9] and 0x34[9] */
diff --git a/sound/soc/codecs/nau8825.h b/sound/soc/codecs/nau8825.h
index 9e6cb62..1293d1b 100644
--- a/sound/soc/codecs/nau8825.h
+++ b/sound/soc/codecs/nau8825.h
@@ -231,6 +231,14 @@
#define NAU8825_I2S_MS_MASTER (1 << NAU8825_I2S_MS_SFT)
#define NAU8825_I2S_MS_SLAVE (0 << NAU8825_I2S_MS_SFT)
+/* BIQ_CTRL (0x20) */
+#define NAU8825_BIQ_WRT_SFT 4
+#define NAU8825_BIQ_WRT_EN (1 << NAU8825_BIQ_WRT_SFT)
+#define NAU8825_BIQ_PATH_SFT 0
+#define NAU8825_BIQ_PATH_MASK (1 << NAU8825_BIQ_PATH_SFT)
+#define NAU8825_BIQ_PATH_ADC (0 << NAU8825_BIQ_PATH_SFT)
+#define NAU8825_BIQ_PATH_DAC (1 << NAU8825_BIQ_PATH_SFT)
+
/* ADC_RATE (0x2b) */
#define NAU8825_ADC_SYNC_DOWN_SFT 0
#define NAU8825_ADC_SYNC_DOWN_MASK 0x3
--
2.6.4
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