The TLV320DAC3100 Audio DAC has 25 built-in digital audio processing blocks
(PRBs). Each of these PRBs has a static filter structure with programmable
coefficients. Once a PRB is selected for use by the DAC, its filter
coefficients can be configured via a dedicated set of registers.
Define a new optional firmware which can be loaded by the TLV320DAC driver.
This firmware describes a full set of filter coefficients for all blocks
used by the various PRBs.
The firmware's binary format is heavily inspired by the one used in the
peb2466 driver. It includes a version marker to allow for potential
evolutions of the format.
Note that adaptive filtering is not supported i.e. filter coefficients are
loaded once before power-on and then cannot be changed while the DAC is
powered. This is why only page A coefficients are modified. Page B
coefficients are only used for adaptive filtering.
Signed-off-by: Romain Gantois <romain.gantois@xxxxxxxxxxx>
---
sound/soc/codecs/tlv320aic31xx.c | 100 +++++++++++++++++++++++++++++++++++++++
1 file changed, 100 insertions(+)
diff --git a/sound/soc/codecs/tlv320aic31xx.c b/sound/soc/codecs/tlv320aic31xx.c
index 2f94cfda0e33..7e624c4b77b6 100644
--- a/sound/soc/codecs/tlv320aic31xx.c
+++ b/sound/soc/codecs/tlv320aic31xx.c
@@ -12,6 +12,7 @@
* and mono/stereo Class-D speaker driver.
*/
+#include <asm/unaligned.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/init.h>
@@ -22,6 +23,7 @@
#include <linux/gpio/consumer.h>
#include <linux/regulator/consumer.h>
#include <linux/acpi.h>
+#include <linux/firmware.h>
#include <linux/of.h>
#include <linux/slab.h>
#include <sound/core.h>
@@ -1638,6 +1640,98 @@ static const struct i2c_device_id aic31xx_i2c_id[] = {
};
MODULE_DEVICE_TABLE(i2c, aic31xx_i2c_id);
+static int tlv320dac3100_fw_load(struct aic31xx_priv *aic31xx,
+ const u8 *data, size_t size)
+{
+ int ret, reg;
+ u16 val16;
+
+ /*
+ * Coefficients firmware binary structure. Multi-byte values are big-endian.
+ *
+ * @0, 16bits: Magic (0xB30C)
+ * @2, 16bits: Version (0x0100 for version 1.0)
+ * @4, 8bits: DAC Processing Block Selection
+ * @5, 62 16-bit values: Page 8 buffer A DAC programmable filter coefficients
+ * @129, 12 16-bit values: Page 9 Buffer A DAC programmable filter coefficients
+ *
+ * Filter coefficients are interpreted as two's complement values
+ * ranging from -32 768 to 32 767. For more details on filter coefficients,
+ * please refer to the TLV320DAC3100 datasheet, tables 6-120 and 6-123.
+ */
+
+ if (size != 153) {
+ dev_err(aic31xx->dev, "firmware size is %zu, expected 153 bytes\n", size);
+ return -EINVAL;
+ }
+
+ /* Check magic */
+ val16 = get_unaligned_be16(data);
+ if (val16 != 0xb30c) {
+ dev_err(aic31xx->dev, "fw magic is 0x%04x expected 0xb30c\n", val16);
+ return -EINVAL;
+ }
+ data += 2;
+
+ /* Check version */
+ val16 = get_unaligned_be16(data);
+ if (val16 != 0x0100) {
+ dev_err(aic31xx->dev, "invalid firmware version 0x%04x! expected 1", val16);
+ return -EINVAL;
+ }
+ data += 2;
+
+ ret = regmap_write(aic31xx->regmap, AIC31XX_DACPRB, *data);
+ if (ret) {
+ dev_err(aic31xx->dev, "failed to write PRB index: err %d\n", ret);
+ return ret;
+ }
+ data += 1;
+
+ /* Page 8 Buffer A coefficients */
+ for (reg = 2; reg < 126; reg++) {
+ ret = regmap_write(aic31xx->regmap, AIC31XX_REG(8, reg), *data);
+ if (ret) {
+ dev_err(aic31xx->dev,
+ "failed to write page 8 filter coefficient %d: err %d\n", reg, ret);
+ return ret;
+ }
+ data++;
+ }
+
+ /* Page 9 Buffer A coefficients */
+ for (reg = 2; reg < 26; reg++) {
+ ret = regmap_write(aic31xx->regmap, AIC31XX_REG(9, reg), *data);
+ if (ret) {
+ dev_err(aic31xx->dev,
+ "failed to write page 9 filter coefficient %d: err %d\n", reg, ret);
+ return ret;
+ }
+ data++;
+ }
+
+ dev_info(aic31xx->dev, "done loading DAC filter coefficients\n");
+
+ return ret;
+}
+
+static int tlv320dac3100_load_coeffs(struct aic31xx_priv *aic31xx,
+ const char *fw_name)
+{
+ const struct firmware *fw;
+ int ret;
+
+ ret = request_firmware(&fw, fw_name, aic31xx->dev);
+ if (ret)
+ return ret;
+
+ ret = tlv320dac3100_fw_load(aic31xx, fw->data, fw->size);
+
+ release_firmware(fw);
+
+ return ret;
+}
+
static int aic31xx_i2c_probe(struct i2c_client *i2c)
{
struct aic31xx_priv *aic31xx;
@@ -1727,6 +1821,12 @@ static int aic31xx_i2c_probe(struct i2c_client *i2c)
}
}
+ if (aic31xx->codec_type == DAC3100) {
+ ret = tlv320dac3100_load_coeffs(aic31xx, "tlv320dac3100-coeffs.bin");
+ if (ret)
+ dev_warn(aic31xx->dev, "Did not load any filter coefficients\n");
+ }
+
if (aic31xx->codec_type & DAC31XX_BIT)
return devm_snd_soc_register_component(&i2c->dev,
&soc_codec_driver_aic31xx,
---
base-commit: 8400291e289ee6b2bf9779ff1c83a291501f017b
change-id: 20240806-tlv320-filter-189edd66496c
Best regards,
--
Romain Gantois <romain.gantois@xxxxxxxxxxx>
