Discussion:
[PATCH] ASoC: ssm4567: Add driver for Analog Devices SSM4567 amplifier
Anatol Pomozov
2014-09-26 16:08:41 UTC
Permalink
Analog Devices SSM4567 is a boost class-D audio amplifier.

Signed-off-by: Anatol Pomozov <***@gmail.com>
---
.../devicetree/bindings/sound/ssm4567.txt | 15 +
sound/soc/codecs/Kconfig | 4 +
sound/soc/codecs/Makefile | 2 +
sound/soc/codecs/ssm4567.c | 350 +++++++++++++++++++++
4 files changed, 371 insertions(+)
create mode 100644 Documentation/devicetree/bindings/sound/ssm4567.txt
create mode 100644 sound/soc/codecs/ssm4567.c

diff --git a/Documentation/devicetree/bindings/sound/ssm4567.txt b/Documentation/devicetree/bindings/sound/ssm4567.txt
new file mode 100644
index 0000000..ec3d9e7
--- /dev/null
+++ b/Documentation/devicetree/bindings/sound/ssm4567.txt
@@ -0,0 +1,15 @@
+Analog Devices SSM4567 audio amplifier
+
+This device supports I2C only.
+
+Required properties:
+ - compatible : Must be "adi,ssm4567"
+ - reg : the I2C address of the device. This will either be 0x34 (LR_SEL/ADDR connected to AGND),
+ 0x35 (LR_SEL/ADDR connected to IOVDD) or 0x36 (LR_SEL/ADDR open).
+
+Example:
+
+ ssm4567: ***@34 {
+ compatible = "adi,ssm4567";
+ reg = <0x34>;
+ };
diff --git a/sound/soc/codecs/Kconfig b/sound/soc/codecs/Kconfig
index 8ab1547..da45b5a 100644
--- a/sound/soc/codecs/Kconfig
+++ b/sound/soc/codecs/Kconfig
@@ -94,6 +94,7 @@ config SND_SOC_ALL_CODECS
select SND_SOC_SSM2518 if I2C
select SND_SOC_SSM2602_SPI if SPI_MASTER
select SND_SOC_SSM2602_I2C if I2C
+ select SND_SOC_SSM4567 if I2C
select SND_SOC_STA32X if I2C
select SND_SOC_STA350 if I2C
select SND_SOC_STA529 if I2C
@@ -546,6 +547,9 @@ config SND_SOC_SSM2602_I2C
select SND_SOC_SSM2602
tristate

+config SND_SOC_SSM4567
+ tristate "Analog Devices ssm4567 amplifier driver support"
+
config SND_SOC_STA32X
tristate

diff --git a/sound/soc/codecs/Makefile b/sound/soc/codecs/Makefile
index afba944..5dce451 100644
--- a/sound/soc/codecs/Makefile
+++ b/sound/soc/codecs/Makefile
@@ -95,6 +95,7 @@ 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-ssm4567-objs := ssm4567.o
snd-soc-sta32x-objs := sta32x.o
snd-soc-sta350-objs := sta350.o
snd-soc-sta529-objs := sta529.o
@@ -266,6 +267,7 @@ 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-$(CONFIG_SND_SOC_SSM4567) += snd-soc-ssm4567.o
obj-$(CONFIG_SND_SOC_STA32X) += snd-soc-sta32x.o
obj-$(CONFIG_SND_SOC_STA350) += snd-soc-sta350.o
obj-$(CONFIG_SND_SOC_STA529) += snd-soc-sta529.o
diff --git a/sound/soc/codecs/ssm4567.c b/sound/soc/codecs/ssm4567.c
new file mode 100644
index 0000000..fb92248
--- /dev/null
+++ b/sound/soc/codecs/ssm4567.c
@@ -0,0 +1,350 @@
+/*
+ * SSM4567 amplifier audio driver
+ *
+ * Copyright 2014 Google Chromium project.
+ * Author: Anatol Pomozov <***@chromium.org>
+ *
+ * Based on code copyright/by:
+ * Copyright 2013 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/i2c.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+#include <linux/gpio.h>
+#include <linux/of_gpio.h>
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+#include <sound/initval.h>
+#include <sound/tlv.h>
+
+#define SSM4567_REG_POWER_CTRL 0x00
+#define SSM4567_REG_AMP_SNS_CTRL 0x01
+#define SSM4567_REG_DAC_CTRL 0x02
+#define SSM4567_REG_DAC_VOLUME 0x03
+#define SSM4567_REG_SAI_CTRL_1 0x04
+#define SSM4567_REG_SAI_CTRL_2 0x05
+#define SSM4567_REG_SAI_PLACEMENT_1 0x06
+#define SSM4567_REG_SAI_PLACEMENT_2 0x07
+#define SSM4567_REG_SAI_PLACEMENT_3 0x08
+#define SSM4567_REG_SAI_PLACEMENT_4 0x09
+#define SSM4567_REG_SAI_PLACEMENT_5 0x0a
+#define SSM4567_REG_SAI_PLACEMENT_6 0x0b
+#define SSM4567_REG_BATTERY_V_OUT 0x0c
+#define SSM4567_REG_LIMITER_CTRL_1 0x0d
+#define SSM4567_REG_LIMITER_CTRL_2 0x0e
+#define SSM4567_REG_LIMITER_CTRL_3 0x0f
+#define SSM4567_REG_STATUS_1 0x10
+#define SSM4567_REG_STATUS_2 0x11
+#define SSM4567_REG_FAULT_CTRL 0x12
+#define SSM4567_REG_PDM_CTRL 0x13
+#define SSM4567_REG_MCLK_RATIO 0x14
+#define SSM4567_REG_BOOST_CTRL_1 0x15
+#define SSM4567_REG_BOOST_CTRL_2 0x16
+#define SSM4567_REG_SOFT_RESET 0xff
+
+/* POWER_CTRL */
+#define SSM4567_POWER_APWDN_EN BIT(7)
+#define SSM4567_POWER_BSNS_PWDN BIT(6)
+#define SSM4567_POWER_VSNS_PWDN BIT(5)
+#define SSM4567_POWER_ISNS_PWDN BIT(4)
+#define SSM4567_POWER_BOOST_PWDN BIT(3)
+#define SSM4567_POWER_AMP_PWDN BIT(2)
+#define SSM4567_POWER_VBAT_ONLY BIT(1)
+#define SSM4567_POWER_SPWDN BIT(0)
+
+/* DAC_CTRL */
+#define SSM4567_DAC_HV BIT(7)
+#define SSM4567_DAC_MUTE BIT(6)
+#define SSM4567_DAC_HPF BIT(5)
+#define SSM4567_DAC_LPM BIT(4)
+#define SSM4567_DAC_FS_MASK 0x7
+#define SSM4567_DAC_FS_8000_12000 0x0
+#define SSM4567_DAC_FS_16000_24000 0x1
+#define SSM4567_DAC_FS_32000_48000 0x2
+#define SSM4567_DAC_FS_64000_96000 0x3
+#define SSM4567_DAC_FS_128000_192000 0x4
+
+struct ssm4567 {
+ struct regmap *regmap;
+};
+
+static const struct reg_default ssm4567_reg_defaults[] = {
+ { SSM4567_REG_POWER_CTRL, 0x81 },
+ { SSM4567_REG_AMP_SNS_CTRL, 0x09 },
+ { SSM4567_REG_DAC_CTRL, 0x32 },
+ { SSM4567_REG_DAC_VOLUME, 0x40 },
+ { SSM4567_REG_SAI_CTRL_1, 0x00 },
+ { SSM4567_REG_SAI_CTRL_2, 0x08 },
+ { SSM4567_REG_SAI_PLACEMENT_1, 0x01 },
+ { SSM4567_REG_SAI_PLACEMENT_2, 0x20 },
+ { SSM4567_REG_SAI_PLACEMENT_3, 0x32 },
+ { SSM4567_REG_SAI_PLACEMENT_4, 0x07 },
+ { SSM4567_REG_SAI_PLACEMENT_5, 0x07 },
+ { SSM4567_REG_SAI_PLACEMENT_6, 0x07 },
+ { SSM4567_REG_BATTERY_V_OUT, 0x00 },
+ { SSM4567_REG_LIMITER_CTRL_1, 0xa4 },
+ { SSM4567_REG_LIMITER_CTRL_2, 0x73 },
+ { SSM4567_REG_LIMITER_CTRL_3, 0x00 },
+ { SSM4567_REG_STATUS_1, 0x00 },
+ { SSM4567_REG_STATUS_2, 0x00 },
+ { SSM4567_REG_FAULT_CTRL, 0x30 },
+ { SSM4567_REG_PDM_CTRL, 0x40 },
+ { SSM4567_REG_MCLK_RATIO, 0x11 },
+ { SSM4567_REG_BOOST_CTRL_1, 0x03 },
+ { SSM4567_REG_BOOST_CTRL_2, 0x00 },
+ { SSM4567_REG_SOFT_RESET, 0x00 },
+};
+
+
+static bool ssm4567_readable_reg(struct device *dev, unsigned int reg)
+{
+ switch (reg) {
+ case SSM4567_REG_POWER_CTRL ... SSM4567_REG_BOOST_CTRL_2:
+ return true;
+ default:
+ return false;
+ }
+
+}
+
+static bool ssm4567_writeable_reg(struct device *dev, unsigned int reg)
+{
+ switch (reg) {
+ case SSM4567_REG_POWER_CTRL ... SSM4567_REG_SAI_PLACEMENT_6:
+ case SSM4567_REG_LIMITER_CTRL_1 ... SSM4567_REG_LIMITER_CTRL_3:
+ case SSM4567_REG_FAULT_CTRL ... SSM4567_REG_BOOST_CTRL_2:
+ /* The datasheet states that soft reset register is read-only,
+ * but logically it is write-only. */
+ case SSM4567_REG_SOFT_RESET:
+ return true;
+ default:
+ return false;
+ }
+}
+
+static bool ssm4567_volatile_reg(struct device *dev, unsigned int reg)
+{
+ switch (reg) {
+ case SSM4567_REG_BATTERY_V_OUT:
+ case SSM4567_REG_STATUS_1 ... SSM4567_REG_STATUS_2:
+ case SSM4567_REG_SOFT_RESET:
+ return true;
+ default:
+ return false;
+ }
+}
+
+static const DECLARE_TLV_DB_MINMAX_MUTE(ssm4567_vol_tlv, -7125, 2400);
+
+static const struct snd_kcontrol_new ssm4567_snd_controls[] = {
+ SOC_SINGLE_TLV("Master Playback Volume", SSM4567_REG_DAC_VOLUME, 0,
+ 0xff, 1, ssm4567_vol_tlv),
+ SOC_SINGLE("Master Playback Switch", SSM4567_REG_DAC_CTRL, 6, 1, 1),
+ SOC_SINGLE("DAC Low Power Mode Switch", SSM4567_REG_DAC_CTRL, 4, 1, 0),
+};
+
+static const struct snd_soc_dapm_widget ssm4567_dapm_widgets[] = {
+ SND_SOC_DAPM_DAC("DAC", "HiFi Playback", SSM4567_REG_POWER_CTRL, 2, 1),
+
+ SND_SOC_DAPM_OUTPUT("OUT"),
+};
+
+static const struct snd_soc_dapm_route ssm4567_routes[] = {
+ { "OUT", NULL, "DAC" },
+};
+
+static int ssm4567_hw_params(struct snd_pcm_substream *substream,
+ struct snd_pcm_hw_params *params, struct snd_soc_dai *dai)
+{
+ struct snd_soc_codec *codec = dai->codec;
+ struct ssm4567 *ssm4567 = snd_soc_codec_get_drvdata(codec);
+ unsigned int rate = params_rate(params);
+ unsigned int dacfs;
+
+ if (rate >= 8000 && rate <= 12000)
+ dacfs = SSM4567_DAC_FS_8000_12000;
+ else if (rate >= 16000 && rate <= 24000)
+ dacfs = SSM4567_DAC_FS_16000_24000;
+ else if (rate >= 32000 && rate <= 48000)
+ dacfs = SSM4567_DAC_FS_32000_48000;
+ else if (rate >= 64000 && rate <= 96000)
+ dacfs = SSM4567_DAC_FS_64000_96000;
+ else if (rate >= 64000 && rate <= 96000)
+ dacfs = SSM4567_DAC_FS_64000_96000;
+ else if (rate >= 128000 && rate <= 192000)
+ dacfs = SSM4567_DAC_FS_128000_192000;
+ else
+ return -EINVAL;
+
+ return regmap_update_bits(ssm4567->regmap, SSM4567_REG_DAC_CTRL,
+ SSM4567_DAC_FS_MASK, dacfs);
+}
+
+static int ssm4567_mute(struct snd_soc_dai *dai, int mute)
+{
+ struct ssm4567 *ssm4567 = snd_soc_codec_get_drvdata(dai->codec);
+ unsigned int val;
+
+ val = mute ? SSM4567_DAC_MUTE : 0;
+ return regmap_update_bits(ssm4567->regmap, SSM4567_REG_DAC_CTRL,
+ SSM4567_DAC_MUTE, val);
+}
+
+static int ssm4567_set_power(struct ssm4567 *ssm4567, bool enable)
+{
+ int ret = 0;
+
+ if (!enable) {
+ ret = regmap_update_bits(ssm4567->regmap,
+ SSM4567_REG_POWER_CTRL,
+ SSM4567_POWER_SPWDN, SSM4567_POWER_SPWDN);
+ regcache_mark_dirty(ssm4567->regmap);
+ }
+
+ regcache_cache_only(ssm4567->regmap, !enable);
+
+ if (enable) {
+ ret = regmap_update_bits(ssm4567->regmap,
+ SSM4567_REG_POWER_CTRL,
+ SSM4567_POWER_SPWDN, 0x00);
+ regcache_sync(ssm4567->regmap);
+ }
+
+ return ret;
+}
+
+static int ssm4567_set_bias_level(struct snd_soc_codec *codec,
+ enum snd_soc_bias_level level)
+{
+ struct ssm4567 *ssm4567 = snd_soc_codec_get_drvdata(codec);
+ int ret = 0;
+
+ switch (level) {
+ case SND_SOC_BIAS_ON:
+ break;
+ case SND_SOC_BIAS_PREPARE:
+ break;
+ case SND_SOC_BIAS_STANDBY:
+ if (codec->dapm.bias_level == SND_SOC_BIAS_OFF)
+ ret = ssm4567_set_power(ssm4567, true);
+ break;
+ case SND_SOC_BIAS_OFF:
+ ret = ssm4567_set_power(ssm4567, false);
+ break;
+ }
+
+ if (ret)
+ return ret;
+
+ codec->dapm.bias_level = level;
+
+ return 0;
+}
+
+#define SSM4567_FORMATS (SNDRV_PCM_FMTBIT_S8 | SNDRV_PCM_FMTBIT_S16_LE | \
+ SNDRV_PCM_FMTBIT_S24_LE | SNDRV_PCM_FMTBIT_S32)
+
+static const struct snd_soc_dai_ops ssm4567_dai_ops = {
+ .hw_params = ssm4567_hw_params,
+ .digital_mute = ssm4567_mute,
+};
+
+static struct snd_soc_dai_driver ssm4567_dai = {
+ .name = "ssm4567-hifi",
+ .playback = {
+ .stream_name = "Playback",
+ .channels_min = 2,
+ .channels_max = 2,
+ .rates = SNDRV_PCM_RATE_8000_192000,
+ .formats = SSM4567_FORMATS,
+ },
+ .ops = &ssm4567_dai_ops,
+};
+
+static struct snd_soc_codec_driver ssm4567_codec_driver = {
+ .set_bias_level = ssm4567_set_bias_level,
+ .idle_bias_off = true,
+
+ .controls = ssm4567_snd_controls,
+ .num_controls = ARRAY_SIZE(ssm4567_snd_controls),
+ .dapm_widgets = ssm4567_dapm_widgets,
+ .num_dapm_widgets = ARRAY_SIZE(ssm4567_dapm_widgets),
+ .dapm_routes = ssm4567_routes,
+ .num_dapm_routes = ARRAY_SIZE(ssm4567_routes),
+};
+
+static const struct regmap_config ssm4567_regmap_config = {
+ .val_bits = 8,
+ .reg_bits = 8,
+
+ .max_register = SSM4567_REG_SOFT_RESET,
+ .readable_reg = ssm4567_readable_reg,
+ .writeable_reg = ssm4567_writeable_reg,
+ .volatile_reg = ssm4567_volatile_reg,
+
+ .cache_type = REGCACHE_RBTREE,
+ .reg_defaults = ssm4567_reg_defaults,
+ .num_reg_defaults = ARRAY_SIZE(ssm4567_reg_defaults),
+};
+
+static int ssm4567_i2c_probe(struct i2c_client *i2c,
+ const struct i2c_device_id *id)
+{
+ struct ssm4567 *ssm4567;
+ int ret;
+
+ ssm4567 = devm_kzalloc(&i2c->dev, sizeof(*ssm4567), GFP_KERNEL);
+ if (ssm4567 == NULL)
+ return -ENOMEM;
+
+ i2c_set_clientdata(i2c, ssm4567);
+
+ ssm4567->regmap = devm_regmap_init_i2c(i2c, &ssm4567_regmap_config);
+ if (IS_ERR(ssm4567->regmap))
+ return PTR_ERR(ssm4567->regmap);
+
+ ret = regmap_write(ssm4567->regmap, SSM4567_REG_SOFT_RESET, 0x00);
+ if (ret)
+ return ret;
+
+ ret = ssm4567_set_power(ssm4567, false);
+ if (ret)
+ return ret;
+
+ return snd_soc_register_codec(&i2c->dev, &ssm4567_codec_driver,
+ &ssm4567_dai, 1);
+}
+
+static int ssm4567_i2c_remove(struct i2c_client *client)
+{
+ snd_soc_unregister_codec(&client->dev);
+ return 0;
+}
+
+static const struct i2c_device_id ssm4567_i2c_ids[] = {
+ { "ssm4567", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, ssm4567_i2c_ids);
+
+static struct i2c_driver ssm4567_driver = {
+ .driver = {
+ .name = "ssm4567",
+ .owner = THIS_MODULE,
+ },
+ .probe = ssm4567_i2c_probe,
+ .remove = ssm4567_i2c_remove,
+ .id_table = ssm4567_i2c_ids,
+};
+module_i2c_driver(ssm4567_driver);
+
+MODULE_DESCRIPTION("ASoC SSM4567 driver");
+MODULE_AUTHOR("Anatol Pomozov <***@chromium.org>");
+MODULE_LICENSE("GPL");
--
2.1.0.rc2.206.gedb03e5
Lars-Peter Clausen
2014-09-26 17:13:45 UTC
Permalink
Post by Anatol Pomozov
Analog Devices SSM4567 is a boost class-D audio amplifier.
Looks mostly okay. I also have a driver for this chip which is getting ready
for upstream. It is a bit more complete feature wise, but I can rebase it
ontop of your driver.

https://github.com/analogdevicesinc/linux/blob/asoc-ssm4329/sound/soc/codecs/ssm4567.c

[...]
Post by Anatol Pomozov
diff --git a/sound/soc/codecs/Kconfig b/sound/soc/codecs/Kconfig
index 8ab1547..da45b5a 100644
--- a/sound/soc/codecs/Kconfig
+++ b/sound/soc/codecs/Kconfig
@@ -94,6 +94,7 @@ config SND_SOC_ALL_CODECS
[...]
Post by Anatol Pomozov
+config SND_SOC_SSM4567
+ tristate "Analog Devices ssm4567 amplifier driver support"
depends on I2C
Post by Anatol Pomozov
+
config SND_SOC_STA32X
tristate
diff --git a/sound/soc/codecs/ssm4567.c b/sound/soc/codecs/ssm4567.c
new file mode 100644
index 0000000..fb92248
--- /dev/null
+++ b/sound/soc/codecs/ssm4567.c
[...]
Post by Anatol Pomozov
+#include <linux/gpio.h>
+#include <linux/of_gpio.h>
No gpios in this driver

[...]
Post by Anatol Pomozov
+
+static const struct snd_kcontrol_new ssm4567_snd_controls[] = {
[...]
Post by Anatol Pomozov
+ SOC_SINGLE("Master Playback Switch", SSM4567_REG_DAC_CTRL, 6, 1, 1),
This one and ...

[...]
Post by Anatol Pomozov
+};
+
[...]
Post by Anatol Pomozov
+static int ssm4567_mute(struct snd_soc_dai *dai, int mute)
+{
+ struct ssm4567 *ssm4567 = snd_soc_codec_get_drvdata(dai->codec);
+ unsigned int val;
+
+ val = mute ? SSM4567_DAC_MUTE : 0;
+ return regmap_update_bits(ssm4567->regmap, SSM4567_REG_DAC_CTRL,
+ SSM4567_DAC_MUTE, val);
... this one control the same bit, so there will be conflicts.
Post by Anatol Pomozov
+}
+
Anatol Pomozov
2014-09-26 20:38:47 UTC
Permalink
Hi
Post by Lars-Peter Clausen
Post by Anatol Pomozov
Analog Devices SSM4567 is a boost class-D audio amplifier.
Looks mostly okay. I also have a driver for this chip which is getting ready
for upstream. It is a bit more complete feature wise,
D'oh I wish I knew it before start working on the driver.
Post by Lars-Peter Clausen
but I can rebase it ontop of your driver.
Thanks!
Post by Lars-Peter Clausen
https://github.com/analogdevicesinc/linux/blob/asoc-ssm4329/sound/soc/codecs/ssm4567.c
[...]
Post by Anatol Pomozov
diff --git a/sound/soc/codecs/Kconfig b/sound/soc/codecs/Kconfig
index 8ab1547..da45b5a 100644
--- a/sound/soc/codecs/Kconfig
+++ b/sound/soc/codecs/Kconfig
@@ -94,6 +94,7 @@ config SND_SOC_ALL_CODECS
[...]
Post by Anatol Pomozov
+config SND_SOC_SSM4567
+ tristate "Analog Devices ssm4567 amplifier driver support"
depends on I2C
Post by Anatol Pomozov
+
config SND_SOC_STA32X
tristate
diff --git a/sound/soc/codecs/ssm4567.c b/sound/soc/codecs/ssm4567.c
new file mode 100644
index 0000000..fb92248
--- /dev/null
+++ b/sound/soc/codecs/ssm4567.c
[...]
Post by Anatol Pomozov
+#include <linux/gpio.h>
+#include <linux/of_gpio.h>
No gpios in this driver
[...]
Post by Anatol Pomozov
+
+static const struct snd_kcontrol_new ssm4567_snd_controls[] = {
[...]
Post by Anatol Pomozov
+ SOC_SINGLE("Master Playback Switch", SSM4567_REG_DAC_CTRL, 6, 1,
1),
This one and ...
[...]
Post by Anatol Pomozov
+};
+
[...]
Post by Anatol Pomozov
+static int ssm4567_mute(struct snd_soc_dai *dai, int mute)
+{
+ struct ssm4567 *ssm4567 = snd_soc_codec_get_drvdata(dai->codec);
+ unsigned int val;
+
+ val = mute ? SSM4567_DAC_MUTE : 0;
+ return regmap_update_bits(ssm4567->regmap, SSM4567_REG_DAC_CTRL,
+ SSM4567_DAC_MUTE, val);
... this one control the same bit, so there will be conflicts.
Post by Anatol Pomozov
+}
+
I've fixed the items you mentioned.

One difference I spotted between your and mine patches is that you
don't call regcache_cache_only(regmap) before powering down the
device. Is it because I2C alive in power down mode? I guess I need to
remove regcache_cache_only() then.
Lars-Peter Clausen
2014-09-26 20:42:20 UTC
Permalink
Post by Anatol Pomozov
I've fixed the items you mentioned.
One difference I spotted between your and mine patches is that you
don't call regcache_cache_only(regmap) before powering down the
device. Is it because I2C alive in power down mode? I guess I need to
remove regcache_cache_only() then.
Yes, the interface should be alive, unless of course you disable the
regulator. But having the regcache_cache_only() should not hurt, except that
we need to resync the registers on power on, which can cause small
additional delays.

- Lars
Anatol Pomozov
2014-09-26 20:31:06 UTC
Permalink
Analog Devices SSM4567 is a boost class-D audio amplifier.

Signed-off-by: Anatol Pomozov <***@gmail.com>
---
.../devicetree/bindings/sound/ssm4567.txt | 15 +
sound/soc/codecs/Kconfig | 5 +
sound/soc/codecs/Makefile | 2 +
sound/soc/codecs/ssm4567.c | 345 +++++++++++++++++++++
4 files changed, 367 insertions(+)
create mode 100644 Documentation/devicetree/bindings/sound/ssm4567.txt
create mode 100644 sound/soc/codecs/ssm4567.c

diff --git a/Documentation/devicetree/bindings/sound/ssm4567.txt b/Documentation/devicetree/bindings/sound/ssm4567.txt
new file mode 100644
index 0000000..ec3d9e7
--- /dev/null
+++ b/Documentation/devicetree/bindings/sound/ssm4567.txt
@@ -0,0 +1,15 @@
+Analog Devices SSM4567 audio amplifier
+
+This device supports I2C only.
+
+Required properties:
+ - compatible : Must be "adi,ssm4567"
+ - reg : the I2C address of the device. This will either be 0x34 (LR_SEL/ADDR connected to AGND),
+ 0x35 (LR_SEL/ADDR connected to IOVDD) or 0x36 (LR_SEL/ADDR open).
+
+Example:
+
+ ssm4567: ***@34 {
+ compatible = "adi,ssm4567";
+ reg = <0x34>;
+ };
diff --git a/sound/soc/codecs/Kconfig b/sound/soc/codecs/Kconfig
index 8ab1547..3eb3efe 100644
--- a/sound/soc/codecs/Kconfig
+++ b/sound/soc/codecs/Kconfig
@@ -94,6 +94,7 @@ config SND_SOC_ALL_CODECS
select SND_SOC_SSM2518 if I2C
select SND_SOC_SSM2602_SPI if SPI_MASTER
select SND_SOC_SSM2602_I2C if I2C
+ select SND_SOC_SSM4567 if I2C
select SND_SOC_STA32X if I2C
select SND_SOC_STA350 if I2C
select SND_SOC_STA529 if I2C
@@ -546,6 +547,10 @@ config SND_SOC_SSM2602_I2C
select SND_SOC_SSM2602
tristate

+config SND_SOC_SSM4567
+ tristate "Analog Devices ssm4567 amplifier driver support"
+ depends on I2C
+
config SND_SOC_STA32X
tristate

diff --git a/sound/soc/codecs/Makefile b/sound/soc/codecs/Makefile
index afba944..5dce451 100644
--- a/sound/soc/codecs/Makefile
+++ b/sound/soc/codecs/Makefile
@@ -95,6 +95,7 @@ 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-ssm4567-objs := ssm4567.o
snd-soc-sta32x-objs := sta32x.o
snd-soc-sta350-objs := sta350.o
snd-soc-sta529-objs := sta529.o
@@ -266,6 +267,7 @@ 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-$(CONFIG_SND_SOC_SSM4567) += snd-soc-ssm4567.o
obj-$(CONFIG_SND_SOC_STA32X) += snd-soc-sta32x.o
obj-$(CONFIG_SND_SOC_STA350) += snd-soc-sta350.o
obj-$(CONFIG_SND_SOC_STA529) += snd-soc-sta529.o
diff --git a/sound/soc/codecs/ssm4567.c b/sound/soc/codecs/ssm4567.c
new file mode 100644
index 0000000..1dadacb
--- /dev/null
+++ b/sound/soc/codecs/ssm4567.c
@@ -0,0 +1,345 @@
+/*
+ * SSM4567 amplifier audio driver
+ *
+ * Copyright 2014 Google Chromium project.
+ * Author: Anatol Pomozov <***@chromium.org>
+ *
+ * Based on code copyright/by:
+ * Copyright 2013 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/i2c.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+#include <sound/initval.h>
+#include <sound/tlv.h>
+
+#define SSM4567_REG_POWER_CTRL 0x00
+#define SSM4567_REG_AMP_SNS_CTRL 0x01
+#define SSM4567_REG_DAC_CTRL 0x02
+#define SSM4567_REG_DAC_VOLUME 0x03
+#define SSM4567_REG_SAI_CTRL_1 0x04
+#define SSM4567_REG_SAI_CTRL_2 0x05
+#define SSM4567_REG_SAI_PLACEMENT_1 0x06
+#define SSM4567_REG_SAI_PLACEMENT_2 0x07
+#define SSM4567_REG_SAI_PLACEMENT_3 0x08
+#define SSM4567_REG_SAI_PLACEMENT_4 0x09
+#define SSM4567_REG_SAI_PLACEMENT_5 0x0a
+#define SSM4567_REG_SAI_PLACEMENT_6 0x0b
+#define SSM4567_REG_BATTERY_V_OUT 0x0c
+#define SSM4567_REG_LIMITER_CTRL_1 0x0d
+#define SSM4567_REG_LIMITER_CTRL_2 0x0e
+#define SSM4567_REG_LIMITER_CTRL_3 0x0f
+#define SSM4567_REG_STATUS_1 0x10
+#define SSM4567_REG_STATUS_2 0x11
+#define SSM4567_REG_FAULT_CTRL 0x12
+#define SSM4567_REG_PDM_CTRL 0x13
+#define SSM4567_REG_MCLK_RATIO 0x14
+#define SSM4567_REG_BOOST_CTRL_1 0x15
+#define SSM4567_REG_BOOST_CTRL_2 0x16
+#define SSM4567_REG_SOFT_RESET 0xff
+
+/* POWER_CTRL */
+#define SSM4567_POWER_APWDN_EN BIT(7)
+#define SSM4567_POWER_BSNS_PWDN BIT(6)
+#define SSM4567_POWER_VSNS_PWDN BIT(5)
+#define SSM4567_POWER_ISNS_PWDN BIT(4)
+#define SSM4567_POWER_BOOST_PWDN BIT(3)
+#define SSM4567_POWER_AMP_PWDN BIT(2)
+#define SSM4567_POWER_VBAT_ONLY BIT(1)
+#define SSM4567_POWER_SPWDN BIT(0)
+
+/* DAC_CTRL */
+#define SSM4567_DAC_HV BIT(7)
+#define SSM4567_DAC_MUTE BIT(6)
+#define SSM4567_DAC_HPF BIT(5)
+#define SSM4567_DAC_LPM BIT(4)
+#define SSM4567_DAC_FS_MASK 0x7
+#define SSM4567_DAC_FS_8000_12000 0x0
+#define SSM4567_DAC_FS_16000_24000 0x1
+#define SSM4567_DAC_FS_32000_48000 0x2
+#define SSM4567_DAC_FS_64000_96000 0x3
+#define SSM4567_DAC_FS_128000_192000 0x4
+
+struct ssm4567 {
+ struct regmap *regmap;
+};
+
+static const struct reg_default ssm4567_reg_defaults[] = {
+ { SSM4567_REG_POWER_CTRL, 0x81 },
+ { SSM4567_REG_AMP_SNS_CTRL, 0x09 },
+ { SSM4567_REG_DAC_CTRL, 0x32 },
+ { SSM4567_REG_DAC_VOLUME, 0x40 },
+ { SSM4567_REG_SAI_CTRL_1, 0x00 },
+ { SSM4567_REG_SAI_CTRL_2, 0x08 },
+ { SSM4567_REG_SAI_PLACEMENT_1, 0x01 },
+ { SSM4567_REG_SAI_PLACEMENT_2, 0x20 },
+ { SSM4567_REG_SAI_PLACEMENT_3, 0x32 },
+ { SSM4567_REG_SAI_PLACEMENT_4, 0x07 },
+ { SSM4567_REG_SAI_PLACEMENT_5, 0x07 },
+ { SSM4567_REG_SAI_PLACEMENT_6, 0x07 },
+ { SSM4567_REG_BATTERY_V_OUT, 0x00 },
+ { SSM4567_REG_LIMITER_CTRL_1, 0xa4 },
+ { SSM4567_REG_LIMITER_CTRL_2, 0x73 },
+ { SSM4567_REG_LIMITER_CTRL_3, 0x00 },
+ { SSM4567_REG_STATUS_1, 0x00 },
+ { SSM4567_REG_STATUS_2, 0x00 },
+ { SSM4567_REG_FAULT_CTRL, 0x30 },
+ { SSM4567_REG_PDM_CTRL, 0x40 },
+ { SSM4567_REG_MCLK_RATIO, 0x11 },
+ { SSM4567_REG_BOOST_CTRL_1, 0x03 },
+ { SSM4567_REG_BOOST_CTRL_2, 0x00 },
+ { SSM4567_REG_SOFT_RESET, 0x00 },
+};
+
+
+static bool ssm4567_readable_reg(struct device *dev, unsigned int reg)
+{
+ switch (reg) {
+ case SSM4567_REG_POWER_CTRL ... SSM4567_REG_BOOST_CTRL_2:
+ return true;
+ default:
+ return false;
+ }
+
+}
+
+static bool ssm4567_writeable_reg(struct device *dev, unsigned int reg)
+{
+ switch (reg) {
+ case SSM4567_REG_POWER_CTRL ... SSM4567_REG_SAI_PLACEMENT_6:
+ case SSM4567_REG_LIMITER_CTRL_1 ... SSM4567_REG_LIMITER_CTRL_3:
+ case SSM4567_REG_FAULT_CTRL ... SSM4567_REG_BOOST_CTRL_2:
+ /* The datasheet states that soft reset register is read-only,
+ * but logically it is write-only. */
+ case SSM4567_REG_SOFT_RESET:
+ return true;
+ default:
+ return false;
+ }
+}
+
+static bool ssm4567_volatile_reg(struct device *dev, unsigned int reg)
+{
+ switch (reg) {
+ case SSM4567_REG_BATTERY_V_OUT:
+ case SSM4567_REG_STATUS_1 ... SSM4567_REG_STATUS_2:
+ case SSM4567_REG_SOFT_RESET:
+ return true;
+ default:
+ return false;
+ }
+}
+
+static const DECLARE_TLV_DB_MINMAX_MUTE(ssm4567_vol_tlv, -7125, 2400);
+
+static const struct snd_kcontrol_new ssm4567_snd_controls[] = {
+ SOC_SINGLE_TLV("Master Playback Volume", SSM4567_REG_DAC_VOLUME, 0,
+ 0xff, 1, ssm4567_vol_tlv),
+ SOC_SINGLE("DAC Low Power Mode Switch", SSM4567_REG_DAC_CTRL, 4, 1, 0),
+};
+
+static const struct snd_soc_dapm_widget ssm4567_dapm_widgets[] = {
+ SND_SOC_DAPM_DAC("DAC", "HiFi Playback", SSM4567_REG_POWER_CTRL, 2, 1),
+
+ SND_SOC_DAPM_OUTPUT("OUT"),
+};
+
+static const struct snd_soc_dapm_route ssm4567_routes[] = {
+ { "OUT", NULL, "DAC" },
+};
+
+static int ssm4567_hw_params(struct snd_pcm_substream *substream,
+ struct snd_pcm_hw_params *params, struct snd_soc_dai *dai)
+{
+ struct snd_soc_codec *codec = dai->codec;
+ struct ssm4567 *ssm4567 = snd_soc_codec_get_drvdata(codec);
+ unsigned int rate = params_rate(params);
+ unsigned int dacfs;
+
+ if (rate >= 8000 && rate <= 12000)
+ dacfs = SSM4567_DAC_FS_8000_12000;
+ else if (rate >= 16000 && rate <= 24000)
+ dacfs = SSM4567_DAC_FS_16000_24000;
+ else if (rate >= 32000 && rate <= 48000)
+ dacfs = SSM4567_DAC_FS_32000_48000;
+ else if (rate >= 64000 && rate <= 96000)
+ dacfs = SSM4567_DAC_FS_64000_96000;
+ else if (rate >= 64000 && rate <= 96000)
+ dacfs = SSM4567_DAC_FS_64000_96000;
+ else if (rate >= 128000 && rate <= 192000)
+ dacfs = SSM4567_DAC_FS_128000_192000;
+ else
+ return -EINVAL;
+
+ return regmap_update_bits(ssm4567->regmap, SSM4567_REG_DAC_CTRL,
+ SSM4567_DAC_FS_MASK, dacfs);
+}
+
+static int ssm4567_mute(struct snd_soc_dai *dai, int mute)
+{
+ struct ssm4567 *ssm4567 = snd_soc_codec_get_drvdata(dai->codec);
+ unsigned int val;
+
+ val = mute ? SSM4567_DAC_MUTE : 0;
+ return regmap_update_bits(ssm4567->regmap, SSM4567_REG_DAC_CTRL,
+ SSM4567_DAC_MUTE, val);
+}
+
+static int ssm4567_set_power(struct ssm4567 *ssm4567, bool enable)
+{
+ int ret = 0;
+
+ if (!enable) {
+ ret = regmap_update_bits(ssm4567->regmap,
+ SSM4567_REG_POWER_CTRL,
+ SSM4567_POWER_SPWDN, SSM4567_POWER_SPWDN);
+ regcache_mark_dirty(ssm4567->regmap);
+ }
+
+ regcache_cache_only(ssm4567->regmap, !enable);
+
+ if (enable) {
+ ret = regmap_update_bits(ssm4567->regmap,
+ SSM4567_REG_POWER_CTRL,
+ SSM4567_POWER_SPWDN, 0x00);
+ regcache_sync(ssm4567->regmap);
+ }
+
+ return ret;
+}
+
+static int ssm4567_set_bias_level(struct snd_soc_codec *codec,
+ enum snd_soc_bias_level level)
+{
+ struct ssm4567 *ssm4567 = snd_soc_codec_get_drvdata(codec);
+ int ret = 0;
+
+ switch (level) {
+ case SND_SOC_BIAS_ON:
+ break;
+ case SND_SOC_BIAS_PREPARE:
+ break;
+ case SND_SOC_BIAS_STANDBY:
+ if (codec->dapm.bias_level == SND_SOC_BIAS_OFF)
+ ret = ssm4567_set_power(ssm4567, true);
+ break;
+ case SND_SOC_BIAS_OFF:
+ ret = ssm4567_set_power(ssm4567, false);
+ break;
+ }
+
+ if (ret)
+ return ret;
+
+ codec->dapm.bias_level = level;
+
+ return 0;
+}
+
+static const struct snd_soc_dai_ops ssm4567_dai_ops = {
+ .hw_params = ssm4567_hw_params,
+ .digital_mute = ssm4567_mute,
+};
+
+static struct snd_soc_dai_driver ssm4567_dai = {
+ .name = "ssm4567-hifi",
+ .playback = {
+ .stream_name = "Playback",
+ .channels_min = 1,
+ .channels_max = 1,
+ .rates = SNDRV_PCM_RATE_8000_192000,
+ .formats = SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S24_LE |
+ SNDRV_PCM_FMTBIT_S32,
+ },
+ .ops = &ssm4567_dai_ops,
+};
+
+static struct snd_soc_codec_driver ssm4567_codec_driver = {
+ .set_bias_level = ssm4567_set_bias_level,
+ .idle_bias_off = true,
+
+ .controls = ssm4567_snd_controls,
+ .num_controls = ARRAY_SIZE(ssm4567_snd_controls),
+ .dapm_widgets = ssm4567_dapm_widgets,
+ .num_dapm_widgets = ARRAY_SIZE(ssm4567_dapm_widgets),
+ .dapm_routes = ssm4567_routes,
+ .num_dapm_routes = ARRAY_SIZE(ssm4567_routes),
+};
+
+static const struct regmap_config ssm4567_regmap_config = {
+ .val_bits = 8,
+ .reg_bits = 8,
+
+ .max_register = SSM4567_REG_SOFT_RESET,
+ .readable_reg = ssm4567_readable_reg,
+ .writeable_reg = ssm4567_writeable_reg,
+ .volatile_reg = ssm4567_volatile_reg,
+
+ .cache_type = REGCACHE_RBTREE,
+ .reg_defaults = ssm4567_reg_defaults,
+ .num_reg_defaults = ARRAY_SIZE(ssm4567_reg_defaults),
+};
+
+static int ssm4567_i2c_probe(struct i2c_client *i2c,
+ const struct i2c_device_id *id)
+{
+ struct ssm4567 *ssm4567;
+ int ret;
+
+ ssm4567 = devm_kzalloc(&i2c->dev, sizeof(*ssm4567), GFP_KERNEL);
+ if (ssm4567 == NULL)
+ return -ENOMEM;
+
+ i2c_set_clientdata(i2c, ssm4567);
+
+ ssm4567->regmap = devm_regmap_init_i2c(i2c, &ssm4567_regmap_config);
+ if (IS_ERR(ssm4567->regmap))
+ return PTR_ERR(ssm4567->regmap);
+
+ ret = regmap_write(ssm4567->regmap, SSM4567_REG_SOFT_RESET, 0x00);
+ if (ret)
+ return ret;
+
+ ret = ssm4567_set_power(ssm4567, false);
+ if (ret)
+ return ret;
+
+ return snd_soc_register_codec(&i2c->dev, &ssm4567_codec_driver,
+ &ssm4567_dai, 1);
+}
+
+static int ssm4567_i2c_remove(struct i2c_client *client)
+{
+ snd_soc_unregister_codec(&client->dev);
+ return 0;
+}
+
+static const struct i2c_device_id ssm4567_i2c_ids[] = {
+ { "ssm4567", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, ssm4567_i2c_ids);
+
+static struct i2c_driver ssm4567_driver = {
+ .driver = {
+ .name = "ssm4567",
+ .owner = THIS_MODULE,
+ },
+ .probe = ssm4567_i2c_probe,
+ .remove = ssm4567_i2c_remove,
+ .id_table = ssm4567_i2c_ids,
+};
+module_i2c_driver(ssm4567_driver);
+
+MODULE_DESCRIPTION("ASoC SSM4567 driver");
+MODULE_AUTHOR("Anatol Pomozov <***@chromium.org>");
+MODULE_LICENSE("GPL");
--
2.1.0.rc2.206.gedb03e5
Lars-Peter Clausen
2014-09-26 20:46:52 UTC
Permalink
Post by Anatol Pomozov
Analog Devices SSM4567 is a boost class-D audio amplifier.
Acked-by: Lars-Peter Clausen <***@metafoo.de>

Thanks.
Anatol Pomozov
2014-09-26 20:49:38 UTC
Permalink
Hi
Post by Anatol Pomozov
Analog Devices SSM4567 is a boost class-D audio amplifier.
Thanks!

Once your changes will be ready I'll be glad to test them. We do not
use output sensing yet but we might do it in the future.
Mark Brown
2014-09-27 10:18:15 UTC
Permalink
Post by Anatol Pomozov
Analog Devices SSM4567 is a boost class-D audio amplifier.
Applied, but don't send patches in reply to existing threads especially
if you don't include a version tag in the header. This was very nearly
Post by Anatol Pomozov
+ ret = regmap_update_bits(ssm4567->regmap,
+ SSM4567_REG_POWER_CTRL,
+ SSM4567_POWER_SPWDN, 0x00);
+ regcache_sync(ssm4567->regmap);
This checks the return value of _update_bits() but not _sync() - make
your mind up please! I'd also split the _set_power() function into two,
there is much more conditional code for the two cases than common code
in there.
Dan Carpenter
2014-10-01 17:02:57 UTC
Permalink
Hello Anatol Pomozov,

The patch 1ee44ce03011: "ASoC: ssm4567: Add driver for Analog Devices
SSM4567 amplifier" from Sep 26, 2014, leads to the following static
checker warning:

sound/soc/codecs/ssm4567.c:176 ssm4567_hw_params()
warn: we tested 'rate <= 96000' before and it was 'false'

sound/soc/codecs/ssm4567.c
160 static int ssm4567_hw_params(struct snd_pcm_substream *substream,
161 struct snd_pcm_hw_params *params, struct snd_soc_dai *dai)
162 {
163 struct snd_soc_codec *codec = dai->codec;
164 struct ssm4567 *ssm4567 = snd_soc_codec_get_drvdata(codec);
165 unsigned int rate = params_rate(params);
166 unsigned int dacfs;
167
168 if (rate >= 8000 && rate <= 12000)
169 dacfs = SSM4567_DAC_FS_8000_12000;
170 else if (rate >= 16000 && rate <= 24000)
171 dacfs = SSM4567_DAC_FS_16000_24000;
172 else if (rate >= 32000 && rate <= 48000)
173 dacfs = SSM4567_DAC_FS_32000_48000;
174 else if (rate >= 64000 && rate <= 96000)
175 dacfs = SSM4567_DAC_FS_64000_96000;
176 else if (rate >= 64000 && rate <= 96000)
177 dacfs = SSM4567_DAC_FS_64000_96000;

These two lines are a cut and paste error. The intent is not clear.

178 else if (rate >= 128000 && rate <= 192000)
179 dacfs = SSM4567_DAC_FS_128000_192000;
180 else
181 return -EINVAL;
182
183 return regmap_update_bits(ssm4567->regmap, SSM4567_REG_DAC_CTRL,
184 SSM4567_DAC_FS_MASK, dacfs);
185 }

regards,
dan carpenter
Anatol Pomozov
2014-10-01 17:12:53 UTC
Permalink
Hi
Post by Dan Carpenter
Hello Anatol Pomozov,
The patch 1ee44ce03011: "ASoC: ssm4567: Add driver for Analog Devices
SSM4567 amplifier" from Sep 26, 2014, leads to the following static
Thanks!

What static checker do you use and how can I run locally?
Post by Dan Carpenter
sound/soc/codecs/ssm4567.c:176 ssm4567_hw_params()
warn: we tested 'rate <= 96000' before and it was 'false'
sound/soc/codecs/ssm4567.c
160 static int ssm4567_hw_params(struct snd_pcm_substream *substream,
161 struct snd_pcm_hw_params *params, struct snd_soc_dai *dai)
162 {
163 struct snd_soc_codec *codec = dai->codec;
164 struct ssm4567 *ssm4567 = snd_soc_codec_get_drvdata(codec);
165 unsigned int rate = params_rate(params);
166 unsigned int dacfs;
167
168 if (rate >= 8000 && rate <= 12000)
169 dacfs = SSM4567_DAC_FS_8000_12000;
170 else if (rate >= 16000 && rate <= 24000)
171 dacfs = SSM4567_DAC_FS_16000_24000;
172 else if (rate >= 32000 && rate <= 48000)
173 dacfs = SSM4567_DAC_FS_32000_48000;
174 else if (rate >= 64000 && rate <= 96000)
175 dacfs = SSM4567_DAC_FS_64000_96000;
176 else if (rate >= 64000 && rate <= 96000)
177 dacfs = SSM4567_DAC_FS_64000_96000;
These two lines are a cut and paste error. The intent is not clear.
It is a copy/paste error. Will send a fix soon.
Post by Dan Carpenter
178 else if (rate >= 128000 && rate <= 192000)
179 dacfs = SSM4567_DAC_FS_128000_192000;
180 else
181 return -EINVAL;
182
183 return regmap_update_bits(ssm4567->regmap, SSM4567_REG_DAC_CTRL,
184 SSM4567_DAC_FS_MASK, dacfs);
185 }
regards,
dan carpenter
Dan Carpenter
2014-10-01 17:44:02 UTC
Permalink
Post by Anatol Pomozov
Hi
Post by Dan Carpenter
Hello Anatol Pomozov,
The patch 1ee44ce03011: "ASoC: ssm4567: Add driver for Analog Devices
SSM4567 amplifier" from Sep 26, 2014, leads to the following static
Thanks!
What static checker do you use and how can I run locally?
This is a smatch warning, but you have to run with the --spammy option
to see it because these warnings are often false postives.

~/progs/smatch/devel/smatch_scripts/kchecker --spammy sound/soc/codecs/ssm4567.c

regards,
dan carpenter

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