2023-05-11 15:14:35

by Martin Povišer

[permalink] [raw]
Subject: [PATCH v2 2/2] ASoC: ssm3515: Add new amp driver

The Analog Devices' SSM3515 is a mono audio amplifier with digital
input, equipped on Apple's 2021 iMacs. Add an ASoC driver for it, and
register both the driver code and schema in MAINTAINERS.

Signed-off-by: Martin Povišer <[email protected]>
---
MAINTAINERS | 2 +
sound/soc/codecs/Kconfig | 6 +
sound/soc/codecs/Makefile | 2 +
sound/soc/codecs/ssm3515.c | 448 +++++++++++++++++++++++++++++++++++++
4 files changed, 458 insertions(+)
create mode 100644 sound/soc/codecs/ssm3515.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 460f953f331b..78136300b026 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1990,9 +1990,11 @@ M: Martin Povišer <[email protected]>
L: [email protected]
L: [email protected] (moderated for non-subscribers)
S: Maintained
+F: Documentation/devicetree/bindings/sound/adi,ssm3515.yaml
F: Documentation/devicetree/bindings/sound/apple,*
F: sound/soc/apple/*
F: sound/soc/codecs/cs42l83-i2c.c
+F: sound/soc/codecs/ssm3515.c

ARM/ARTPEC MACHINE SUPPORT
M: Jesper Nilsson <[email protected]>
diff --git a/sound/soc/codecs/Kconfig b/sound/soc/codecs/Kconfig
index 8020097d4e4c..d5665c21b6f3 100644
--- a/sound/soc/codecs/Kconfig
+++ b/sound/soc/codecs/Kconfig
@@ -1652,6 +1652,12 @@ config SND_SOC_SSM2602_I2C
select SND_SOC_SSM2602
select REGMAP_I2C

+config SND_SOC_SSM3515
+ tristate "Analog Devices SSM3515 amplifier driver"
+ select REGMAP_I2C
+ depends on I2C
+ depends on OF
+
config SND_SOC_SSM4567
tristate "Analog Devices ssm4567 amplifier driver support"
depends on I2C
diff --git a/sound/soc/codecs/Makefile b/sound/soc/codecs/Makefile
index 5cdbae88e6e3..8a35bc01c486 100644
--- a/sound/soc/codecs/Makefile
+++ b/sound/soc/codecs/Makefile
@@ -256,6 +256,7 @@ snd-soc-ssm2518-objs := ssm2518.o
snd-soc-ssm2602-objs := ssm2602.o
snd-soc-ssm2602-spi-objs := ssm2602-spi.o
snd-soc-ssm2602-i2c-objs := ssm2602-i2c.o
+snd-soc-ssm3515-objs := ssm3515.o
snd-soc-ssm4567-objs := ssm4567.o
snd-soc-sta32x-objs := sta32x.o
snd-soc-sta350-objs := sta350.o
@@ -623,6 +624,7 @@ obj-$(CONFIG_SND_SOC_SSM2518) += snd-soc-ssm2518.o
obj-$(CONFIG_SND_SOC_SSM2602) += snd-soc-ssm2602.o
obj-$(CONFIG_SND_SOC_SSM2602_SPI) += snd-soc-ssm2602-spi.o
obj-$(CONFIG_SND_SOC_SSM2602_I2C) += snd-soc-ssm2602-i2c.o
+obj-$(CONFIG_SND_SOC_SSM3515) += snd-soc-ssm3515.o
obj-$(CONFIG_SND_SOC_SSM4567) += snd-soc-ssm4567.o
obj-$(CONFIG_SND_SOC_STA32X) += snd-soc-sta32x.o
obj-$(CONFIG_SND_SOC_STA350) += snd-soc-sta350.o
diff --git a/sound/soc/codecs/ssm3515.c b/sound/soc/codecs/ssm3515.c
new file mode 100644
index 000000000000..784e890031a4
--- /dev/null
+++ b/sound/soc/codecs/ssm3515.c
@@ -0,0 +1,448 @@
+// SPDX-License-Identifier: GPL-2.0-only OR MIT
+//
+// Analog Devices' SSM3515 audio amp driver
+//
+// Copyright (C) The Asahi Linux Contributors
+
+#include <linux/bits.h>
+#include <linux/bitfield.h>
+#include <linux/device.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/regmap.h>
+
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+#include <sound/tlv.h>
+
+
+#define SSM3515_PWR 0x00
+#define SSM3515_PWR_APWDN_EN BIT(7)
+#define SSM3515_PWR_BSNS_PWDN BIT(6)
+#define SSM3515_PWR_S_RST BIT(1)
+#define SSM3515_PWR_SPWDN BIT(0)
+
+#define SSM3515_GEC 0x01
+#define SSM3515_GEC_EDGE BIT(4)
+#define SSM3515_GEC_EDGE_SHIFT 4
+#define SSM3515_GEC_ANA_GAIN GENMASK(1, 0)
+
+#define SSM3515_DAC 0x02
+#define SSM3515_DAC_HV BIT(7)
+#define SSM3515_DAC_MUTE BIT(6)
+#define SSM3515_DAC_HPF BIT(5)
+#define SSM3515_DAC_LPM BIT(4)
+#define SSM3515_DAC_FS GENMASK(2, 0)
+
+#define SSM3515_DAC_VOL 0x03
+
+#define SSM3515_SAI1 0x04
+#define SSM3515_SAI1_DAC_POL BIT(7)
+#define SSM3515_SAI1_BCLK_POL BIT(6)
+#define SSM3515_SAI1_TDM_BCLKS GENMASK(5, 3)
+#define SSM3515_SAI1_FSYNC_MODE BIT(2)
+#define SSM3515_SAI1_SDATA_FMT BIT(1)
+#define SSM3515_SAI1_SAI_MODE BIT(0)
+
+#define SSM3515_SAI2 0x05
+#define SSM3515_SAI2_DATA_WIDTH BIT(7)
+#define SSM3515_SAI2_AUTO_SLOT BIT(4)
+#define SSM3515_SAI2_TDM_SLOT GENMASK(3, 0)
+
+#define SSM3515_VBAT_OUT 0x06
+
+#define SSM3515_STATUS 0x0a
+#define SSM3515_STATUS_UVLO_REG BIT(6)
+#define SSM3515_STATUS_LIM_EG BIT(5)
+#define SSM3515_STATUS_CLIP BIT(4)
+#define SSM3515_STATUS_AMP_OC BIT(3)
+#define SSM3515_STATUS_OTF BIT(2)
+#define SSM3515_STATUS_OTW BIT(1)
+#define SSM3515_STATUS_BAT_WARN BIT(0)
+
+static bool ssm3515_volatile_reg(struct device *dev, unsigned int reg)
+{
+ switch (reg) {
+ case SSM3515_STATUS:
+ case SSM3515_VBAT_OUT:
+ return true;
+
+ default:
+ return false;
+ }
+}
+
+static const struct reg_default ssm3515_reg_defaults[] = {
+ { SSM3515_PWR, 0x81 },
+ { SSM3515_GEC, 0x01 },
+ { SSM3515_DAC, 0x32 },
+ { SSM3515_DAC_VOL, 0x40 },
+ { SSM3515_SAI1, 0x11 },
+ { SSM3515_SAI2, 0x00 },
+};
+
+static const struct regmap_config ssm3515_i2c_regmap = {
+ .reg_bits = 8,
+ .val_bits = 8,
+ .volatile_reg = ssm3515_volatile_reg,
+ .max_register = 0xb,
+ .reg_defaults = ssm3515_reg_defaults,
+ .num_reg_defaults = ARRAY_SIZE(ssm3515_reg_defaults),
+ .cache_type = REGCACHE_FLAT,
+};
+
+struct ssm3515_data {
+ struct device *dev;
+ struct regmap *regmap;
+};
+
+// The specced range is -71.25...24.00 dB with step size of 0.375 dB,
+// and a mute item below that. This is represented by -71.62...24.00 dB
+// with the mute item mapped onto the low end.
+static DECLARE_TLV_DB_MINMAX_MUTE(ssm3515_dac_volume, -7162, 2400);
+
+static const char * const ssm3515_ana_gain_text[] = {
+ "8.4 V Span", "12.6 V Span", "14 V Span", "15 V Span",
+};
+
+static SOC_ENUM_SINGLE_DECL(ssm3515_ana_gain_enum, SSM3515_GEC,
+ __bf_shf(SSM3515_GEC_ANA_GAIN),
+ ssm3515_ana_gain_text);
+
+static const struct snd_kcontrol_new ssm3515_snd_controls[] = {
+ SOC_SINGLE_TLV("DAC Playback Volume", SSM3515_DAC_VOL,
+ 0, 255, 1, ssm3515_dac_volume),
+ SOC_SINGLE("Low EMI Mode Switch", SSM3515_GEC,
+ __bf_shf(SSM3515_GEC_EDGE), 1, 0),
+ SOC_SINGLE("Soft Volume Ramping Switch", SSM3515_DAC,
+ __bf_shf(SSM3515_DAC_HV), 1, 1),
+ SOC_SINGLE("HPF Switch", SSM3515_DAC,
+ __bf_shf(SSM3515_DAC_HPF), 1, 0),
+ SOC_SINGLE("DAC Invert Switch", SSM3515_SAI1,
+ __bf_shf(SSM3515_SAI1_DAC_POL), 1, 0),
+ SOC_ENUM("DAC Analog Gain Select", ssm3515_ana_gain_enum),
+};
+
+static void ssm3515_read_faults(struct snd_soc_component *component)
+{
+ int ret;
+
+ ret = snd_soc_component_read(component, SSM3515_STATUS);
+ if (ret <= 0) {
+ /*
+ * If the read was erroneous, ASoC core has printed a message,
+ * and that's all that's appropriate in handling the error here.
+ */
+ return;
+ }
+
+ dev_err(component->dev, "device reports:%s%s%s%s%s%s%s\n",
+ FIELD_GET(SSM3515_STATUS_UVLO_REG, ret) ? " voltage regulator fault" : "",
+ FIELD_GET(SSM3515_STATUS_LIM_EG, ret) ? " limiter engaged" : "",
+ FIELD_GET(SSM3515_STATUS_CLIP, ret) ? " clipping detected" : "",
+ FIELD_GET(SSM3515_STATUS_AMP_OC, ret) ? " amp over-current fault" : "",
+ FIELD_GET(SSM3515_STATUS_OTF, ret) ? " overtemperature fault" : "",
+ FIELD_GET(SSM3515_STATUS_OTW, ret) ? " overtemperature warning" : "",
+ FIELD_GET(SSM3515_STATUS_BAT_WARN, ret) ? " bat voltage low warning" : "");
+}
+
+static int ssm3515_probe(struct snd_soc_component *component)
+{
+ int ret;
+
+ /* Start out muted */
+ ret = snd_soc_component_update_bits(component, SSM3515_DAC,
+ SSM3515_DAC_MUTE, SSM3515_DAC_MUTE);
+ if (ret < 0)
+ return ret;
+
+ /* Disable the 'master power-down' */
+ ret = snd_soc_component_update_bits(component, SSM3515_PWR,
+ SSM3515_PWR_SPWDN, 0);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static int ssm3515_mute(struct snd_soc_dai *dai, int mute, int direction)
+{
+ int ret;
+
+ ret = snd_soc_component_update_bits(dai->component,
+ SSM3515_DAC,
+ SSM3515_DAC_MUTE,
+ FIELD_PREP(SSM3515_DAC_MUTE, mute));
+ if (ret < 0)
+ return ret;
+ return 0;
+}
+
+static int ssm3515_hw_params(struct snd_pcm_substream *substream,
+ struct snd_pcm_hw_params *params,
+ struct snd_soc_dai *dai)
+{
+ struct snd_soc_component *component = dai->component;
+ int ret, rateval;
+
+ switch (params_format(params)) {
+ case SNDRV_PCM_FORMAT_S16:
+ case SNDRV_PCM_FORMAT_S24:
+ ret = snd_soc_component_update_bits(component,
+ SSM3515_SAI2, SSM3515_SAI2_DATA_WIDTH,
+ FIELD_PREP(SSM3515_SAI2_DATA_WIDTH,
+ params_width(params) == 16));
+ if (ret < 0)
+ return ret;
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ switch (params_rate(params)) {
+ case 8000 ... 12000:
+ rateval = 0;
+ break;
+ case 16000 ... 24000:
+ rateval = 1;
+ break;
+ case 32000 ... 48000:
+ rateval = 2;
+ break;
+ case 64000 ... 96000:
+ rateval = 3;
+ break;
+ case 128000 ... 192000:
+ rateval = 4;
+ break;
+ case 48001 ... 63999: /* this is ...72000 but overlaps */
+ rateval = 5;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ ret = snd_soc_component_update_bits(component,
+ SSM3515_DAC, SSM3515_DAC_FS,
+ FIELD_PREP(SSM3515_DAC_FS, rateval));
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static int ssm3515_set_fmt(struct snd_soc_dai *dai, unsigned int fmt)
+{
+ struct snd_soc_component *component = dai->component;
+ bool fpol_inv = false; /* non-inverted: frame starts with low-to-high FSYNC */
+ int ret;
+ u8 sai1 = 0;
+
+ switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
+ case SND_SOC_DAIFMT_IB_NF:
+ case SND_SOC_DAIFMT_IB_IF:
+ sai1 |= SSM3515_SAI1_BCLK_POL;
+ break;
+ }
+
+ switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
+ case SND_SOC_DAIFMT_I2S:
+ fpol_inv = 1;
+ sai1 &= ~SSM3515_SAI1_SDATA_FMT; /* 1 bit start delay */
+ break;
+ case SND_SOC_DAIFMT_LEFT_J:
+ fpol_inv = 0;
+ sai1 |= SSM3515_SAI1_SDATA_FMT; /* no start delay */
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
+ case SND_SOC_DAIFMT_NB_IF:
+ case SND_SOC_DAIFMT_IB_IF:
+ fpol_inv ^= 1;
+ break;
+ }
+
+ /* Set the serial input to 'TDM mode' */
+ sai1 |= SSM3515_SAI1_SAI_MODE;
+
+ if (fpol_inv) {
+ /*
+ * We configure the codec in a 'TDM mode', in which the
+ * FSYNC_MODE bit of SAI1 is supposed to select between
+ * what the datasheet calls 'Pulsed FSYNC mode' and '50%
+ * FSYNC mode'.
+ *
+ * Experiments suggest that this bit in fact simply selects
+ * the FSYNC polarity, so go with that.
+ */
+ sai1 |= SSM3515_SAI1_FSYNC_MODE;
+ }
+
+ ret = snd_soc_component_update_bits(component, SSM3515_SAI1,
+ SSM3515_SAI1_BCLK_POL | SSM3515_SAI1_SDATA_FMT |
+ SSM3515_SAI1_SAI_MODE | SSM3515_SAI1_FSYNC_MODE, sai1);
+
+ if (ret < 0)
+ return ret;
+ return 0;
+}
+
+static int ssm3515_set_tdm_slot(struct snd_soc_dai *dai,
+ unsigned int tx_mask,
+ unsigned int rx_mask,
+ int slots, int slot_width)
+{
+ struct snd_soc_component *component = dai->component;
+ int slot, tdm_bclks_val, ret;
+
+ if (tx_mask == 0 || rx_mask != 0)
+ return -EINVAL;
+
+ slot = __ffs(tx_mask);
+
+ if (tx_mask & ~BIT(slot))
+ return -EINVAL;
+
+ switch (slot_width) {
+ case 16:
+ tdm_bclks_val = 0;
+ break;
+ case 24:
+ tdm_bclks_val = 1;
+ break;
+ case 32:
+ tdm_bclks_val = 2;
+ break;
+ case 48:
+ tdm_bclks_val = 3;
+ break;
+ case 64:
+ tdm_bclks_val = 4;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ ret = snd_soc_component_update_bits(component, SSM3515_SAI1,
+ SSM3515_SAI1_TDM_BCLKS,
+ FIELD_PREP(SSM3515_SAI1_TDM_BCLKS, tdm_bclks_val));
+ if (ret < 0)
+ return ret;
+
+ ret = snd_soc_component_update_bits(component, SSM3515_SAI2,
+ SSM3515_SAI2_TDM_SLOT,
+ FIELD_PREP(SSM3515_SAI2_TDM_SLOT, slot));
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static int ssm3515_hw_free(struct snd_pcm_substream *substream,
+ struct snd_soc_dai *dai)
+{
+ /*
+ * We don't get live notification of faults, so at least at
+ * this time, when playback is over, check if we have tripped
+ * over anything and if so, log it.
+ */
+ ssm3515_read_faults(dai->component);
+ return 0;
+}
+
+static const struct snd_soc_dai_ops ssm3515_dai_ops = {
+ .mute_stream = ssm3515_mute,
+ .hw_params = ssm3515_hw_params,
+ .set_fmt = ssm3515_set_fmt,
+ .set_tdm_slot = ssm3515_set_tdm_slot,
+ .hw_free = ssm3515_hw_free,
+};
+
+static struct snd_soc_dai_driver ssm3515_dai_driver = {
+ .name = "SSM3515 SAI",
+ .id = 0,
+ .playback = {
+ .stream_name = "Playback",
+ .channels_min = 1,
+ .channels_max = 1,
+ .rates = SNDRV_PCM_RATE_CONTINUOUS,
+ .formats = SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S24_LE,
+ },
+ .ops = &ssm3515_dai_ops,
+};
+
+static const struct snd_soc_dapm_widget ssm3515_dapm_widgets[] = {
+ SND_SOC_DAPM_DAC("DAC", NULL, SND_SOC_NOPM, 0, 0),
+ SND_SOC_DAPM_OUTPUT("OUT"),
+};
+
+static const struct snd_soc_dapm_route ssm3515_dapm_routes[] = {
+ {"OUT", NULL, "DAC"},
+ {"DAC", NULL, "Playback"},
+};
+
+static const struct snd_soc_component_driver ssm3515_asoc_component = {
+ .probe = ssm3515_probe,
+ .controls = ssm3515_snd_controls,
+ .num_controls = ARRAY_SIZE(ssm3515_snd_controls),
+ .dapm_widgets = ssm3515_dapm_widgets,
+ .num_dapm_widgets = ARRAY_SIZE(ssm3515_dapm_widgets),
+ .dapm_routes = ssm3515_dapm_routes,
+ .num_dapm_routes = ARRAY_SIZE(ssm3515_dapm_routes),
+ .endianness = 1,
+};
+
+static int ssm3515_i2c_probe(struct i2c_client *client)
+{
+ struct ssm3515_data *data;
+ int ret;
+
+ data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->dev = &client->dev;
+ i2c_set_clientdata(client, data);
+
+ data->regmap = devm_regmap_init_i2c(client, &ssm3515_i2c_regmap);
+ if (IS_ERR(data->regmap))
+ return dev_err_probe(data->dev, PTR_ERR(data->regmap),
+ "initializing register map\n");
+
+ /* Perform a reset */
+ ret = regmap_update_bits(data->regmap, SSM3515_PWR,
+ SSM3515_PWR_S_RST, SSM3515_PWR_S_RST);
+ if (ret < 0)
+ return dev_err_probe(data->dev, ret,
+ "performing software reset\n");
+ regmap_reinit_cache(data->regmap, &ssm3515_i2c_regmap);
+
+ return devm_snd_soc_register_component(data->dev,
+ &ssm3515_asoc_component,
+ &ssm3515_dai_driver, 1);
+}
+
+static const struct of_device_id ssm3515_of_match[] = {
+ { .compatible = "adi,ssm3515" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, ssm3515_of_match);
+
+static struct i2c_driver ssm3515_i2c_driver = {
+ .driver = {
+ .name = "ssm3515",
+ .of_match_table = of_match_ptr(ssm3515_of_match),
+ },
+ .probe_new = ssm3515_i2c_probe,
+};
+module_i2c_driver(ssm3515_i2c_driver);
+
+MODULE_AUTHOR("Martin Povišer <[email protected]>");
+MODULE_DESCRIPTION("ASoC SSM3515 audio amp driver");
+MODULE_LICENSE("Dual MIT/GPL");
--
2.38.3