[PATCH 0/3] Add the Renesas X9250 potentiometers ASoC support

[PATCH 0/3] Add the Renesas X9250 potentiometers ASoC support

[Herve Codina]

Hi,

The Renesas X9250 is a quad digitally controlled potentiometers.

In the audio path, it can be present on amplifiers designs and it can
be used in ALSA as an auxiliary audio device to control these amplifiers.

Best regards,
Herve Codina

Herve Codina (3):
  dt-bindings: sound: Add the Renesas X9250 potentiometers
  ASoC: codecs: Add support for the Renesas X9250 potentiometers
  MAINTAINERS: add the Renesas X9250 ASoC entry

 .../bindings/sound/renesas,x9250.yaml         |  60 ++++
 MAINTAINERS                                   |   7 +
 sound/soc/codecs/Kconfig                      |  11 +
 sound/soc/codecs/Makefile                     |   2 +
 sound/soc/codecs/x9250.c                      | 276 ++++++++++++++++++
 5 files changed, 356 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/sound/renesas,x9250.yaml
 create mode 100644 sound/soc/codecs/x9250.c

-- 
2.39.0

[PATCH 1/3] dt-bindings: sound: Add the Renesas X9250 potentiometers

[Herve Codina]

The Renesas X9250 is a quad digitally controlled potentiometers.

Signed-off-by: Herve Codina <herve.codina@bootlin.com>
---
 .../bindings/sound/renesas,x9250.yaml         | 60 +++++++++++++++++++
 1 file changed, 60 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/sound/renesas,x9250.yaml

diff --git a/Documentation/devicetree/bindings/sound/renesas,x9250.yaml b/Documentation/devicetree/bindings/sound/renesas,x9250.yaml
new file mode 100644
index 000000000000..ad29ef465a18
--- /dev/null
+++ b/Documentation/devicetree/bindings/sound/renesas,x9250.yaml
@@ -0,0 +1,60 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/sound/renesas,x9250.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Renesas X9250 quad potentiometers
+
+maintainers:
+  - Herve Codina <herve.codina@bootlin.com>
+
+description: |
+  The Renesas X9250 is a quad digitally controlled potentiometers.
+
+  In the audio path, it can be present on amplifiers designs and it can be used
+  in ALSA as an auxiliary audio device to control these amplifiers.
+
+allOf:
+  - $ref: /schemas/spi/spi-peripheral-props.yaml
+  - $ref: dai-common.yaml#
+
+properties:
+  compatible:
+    const: renesas,x9250
+
+  reg:
+    description:
+      SPI device address.
+    maxItems: 1
+
+  spi-max-frequency:
+    maximum: 2000000
+
+patternProperties:
+  "^renesas,cmd[0-3]-invert$":
+    description:
+      The related command is inverted meaning that the minimum command value
+      set the wiper to Rh and the maximum command value set the wiper to Rl.
+      Without this property, the minimum command value set the wiper to Rl and
+      the maximum to Rh.
+    type: boolean
+
+required:
+  - compatible
+  - reg
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    spi {
+        #address-cells = <1>;
+        #size-cells = <0>;
+        x9250@0 {
+            compatible = "renesas,x9250";
+            reg = <0>;
+            spi-max-frequency = <2000000>;
+            renesas,cmd3-invert;
+        };
+    };
-- 
2.39.0

[PATCH 2/3] ASoC: codecs: Add support for the Renesas X9250 potentiometers

[Herve Codina]

The Renesas X9250 is a quad digitally controlled potentiometers.

Signed-off-by: Herve Codina <herve.codina@bootlin.com>
---
 sound/soc/codecs/Kconfig  |  11 ++
 sound/soc/codecs/Makefile |   2 +
 sound/soc/codecs/x9250.c  | 276 ++++++++++++++++++++++++++++++++++++++
 3 files changed, 289 insertions(+)
 create mode 100644 sound/soc/codecs/x9250.c

diff --git a/sound/soc/codecs/Kconfig b/sound/soc/codecs/Kconfig
index 5531bf8d4b3f..19afa0067305 100644
--- a/sound/soc/codecs/Kconfig
+++ b/sound/soc/codecs/Kconfig
@@ -314,6 +314,7 @@ config SND_SOC_ALL_CODECS
 	imply SND_SOC_WM9713
 	imply SND_SOC_WSA881X
 	imply SND_SOC_WSA883X
+	imply SND_SOC_X9250
 	imply SND_SOC_ZL38060
 	help
 	  Normally ASoC codec drivers are only built if a machine driver which
@@ -2053,6 +2054,16 @@ config SND_SOC_WSA883X
 	  This enables support for Qualcomm WSA8830/WSA8835 Class-D
 	  Smart Speaker Amplifier.
 
+config SND_SOC_X9250
+	tristate "Renesas X9250 quad controlled potentiometers"
+	depends on SPI
+	help
+	  Enable support for the Renesas X9250 quad controlled
+	  potentiometers.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called snd-soc-x9250.
+
 config SND_SOC_ZL38060
 	tristate "Microsemi ZL38060 Connected Home Audio Processor"
 	depends on SPI_MASTER
diff --git a/sound/soc/codecs/Makefile b/sound/soc/codecs/Makefile
index bcf95de654fd..a1d6de6a18f6 100644
--- a/sound/soc/codecs/Makefile
+++ b/sound/soc/codecs/Makefile
@@ -346,6 +346,7 @@ snd-soc-wm9713-objs := wm9713.o
 snd-soc-wm-hubs-objs := wm_hubs.o
 snd-soc-wsa881x-objs := wsa881x.o
 snd-soc-wsa883x-objs := wsa883x.o
+snd-soc-x9250-objs := x9250.o
 snd-soc-zl38060-objs := zl38060.o
 # Amp
 snd-soc-max9877-objs := max9877.o
@@ -708,6 +709,7 @@ obj-$(CONFIG_SND_SOC_WM_ADSP)	+= snd-soc-wm-adsp.o
 obj-$(CONFIG_SND_SOC_WM_HUBS)	+= snd-soc-wm-hubs.o
 obj-$(CONFIG_SND_SOC_WSA881X)	+= snd-soc-wsa881x.o
 obj-$(CONFIG_SND_SOC_WSA883X)	+= snd-soc-wsa883x.o
+obj-$(CONFIG_SND_SOC_X9250)	+= snd-soc-x9250.o
 obj-$(CONFIG_SND_SOC_ZL38060)	+= snd-soc-zl38060.o
 
 # Amp
diff --git a/sound/soc/codecs/x9250.c b/sound/soc/codecs/x9250.c
new file mode 100644
index 000000000000..14f80009f085
--- /dev/null
+++ b/sound/soc/codecs/x9250.c
@@ -0,0 +1,276 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// x9250.c  --  Renesas X9250 ALSA SoC driver
+//
+// Copyright 2023 CS GROUP France
+//
+// Author: Herve Codina <herve.codina@bootlin.com>
+
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/spi/spi.h>
+#include <sound/soc.h>
+#include <sound/tlv.h>
+
+#define X9250_NB_CHANNEL	4
+
+struct x9250 {
+	struct spi_device *spi;
+	u8 spi_tx_buf[3]; /* Cannot use stack area for SPI (dma-safe memory) */
+	u8 spi_rx_buf[3]; /* Cannot use stack area for SPI (dma-safe memory) */
+	int cmd_inv;
+};
+
+#define X9250_CMD_RD_WCR(_p)    (0x90 | (_p))
+#define X9250_CMD_WR_WCR(_p)    (0xa0 | (_p))
+
+static int x9250_write8(struct x9250 *x9250, u8 cmd, u8 val)
+{
+	struct spi_transfer xfer = {
+		.tx_buf = &x9250->spi_tx_buf,
+		.len = 3,
+	};
+
+	BUILD_BUG_ON(sizeof(x9250->spi_tx_buf) < 3);
+
+	x9250->spi_tx_buf[0] = 0x50;
+	x9250->spi_tx_buf[1] = cmd;
+	x9250->spi_tx_buf[2] = val;
+
+	return spi_sync_transfer(x9250->spi, &xfer, 1);
+}
+
+static int x9250_read8(struct x9250 *x9250, u8 cmd, u8 *val)
+{
+	struct spi_transfer xfer = {
+		.tx_buf = &x9250->spi_tx_buf,
+		.rx_buf = &x9250->spi_rx_buf,
+		.len = 3,
+	};
+	int ret;
+
+	BUILD_BUG_ON(sizeof(x9250->spi_tx_buf) < 3);
+	BUILD_BUG_ON(sizeof(x9250->spi_rx_buf) < 3);
+
+	x9250->spi_tx_buf[0] = 0x50;
+	x9250->spi_tx_buf[1] = cmd;
+
+	ret = spi_sync_transfer(x9250->spi, &xfer, 1);
+	if (ret)
+		return ret;
+
+	*val = x9250->spi_rx_buf[2];
+	return 0;
+}
+
+static const struct snd_soc_dapm_widget x9250_dapm_widgets[] = {
+	SND_SOC_DAPM_INPUT("IN0"),
+	SND_SOC_DAPM_INPUT("IN1"),
+	SND_SOC_DAPM_INPUT("IN2"),
+	SND_SOC_DAPM_INPUT("IN3"),
+
+	SND_SOC_DAPM_PGA("CH0 PGA", SND_SOC_NOPM, 0, 0, NULL, 0),
+	SND_SOC_DAPM_PGA("CH1 PGA", SND_SOC_NOPM, 0, 0, NULL, 0),
+	SND_SOC_DAPM_PGA("CH2 PGA", SND_SOC_NOPM, 0, 0, NULL, 0),
+	SND_SOC_DAPM_PGA("CH3 PGA", SND_SOC_NOPM, 0, 0, NULL, 0),
+
+	SND_SOC_DAPM_OUTPUT("OUT0"),
+	SND_SOC_DAPM_OUTPUT("OUT1"),
+	SND_SOC_DAPM_OUTPUT("OUT2"),
+	SND_SOC_DAPM_OUTPUT("OUT3"),
+};
+
+static const struct snd_soc_dapm_route x9250_dapm_routes[] = {
+	{ "CH0 PGA", NULL, "IN0" },
+	{ "CH1 PGA", NULL, "IN1" },
+	{ "CH2 PGA", NULL, "IN2" },
+	{ "CH3 PGA", NULL, "IN3" },
+
+	{ "OUT0", NULL, "CH0 PGA" },
+	{ "OUT1", NULL, "CH1 PGA" },
+	{ "OUT2", NULL, "CH2 PGA" },
+	{ "OUT3", NULL, "CH3 PGA" },
+};
+
+static int x8250_kctrl_cmd_get(struct snd_kcontrol *kcontrol,
+			       struct snd_ctl_elem_value *ucontrol)
+{
+	struct soc_mixer_control *mc = (struct soc_mixer_control *)kcontrol->private_value;
+	struct snd_soc_component *component = snd_soc_kcontrol_component(kcontrol);
+	struct x9250 *x9250 = snd_soc_component_get_drvdata(component);
+	int min = mc->min;
+	int max = mc->max;
+	unsigned int mask = (1 << fls(max)) - 1;
+	unsigned int invert = mc->invert;
+	int ret;
+	u8 val;
+	u8 wcr;
+
+	wcr = mc->reg;
+	if (wcr > 4)
+		return -EINVAL;
+
+	ret = x9250_read8(x9250, X9250_CMD_RD_WCR(wcr), &val);
+	if (ret)
+		return ret;
+
+	ucontrol->value.integer.value[0] = (val & mask) - min;
+	if (invert)
+		ucontrol->value.integer.value[0] = max - ucontrol->value.integer.value[0];
+
+	return 0;
+}
+
+static int x8250_kctrl_cmd_put(struct snd_kcontrol *kcontrol,
+			       struct snd_ctl_elem_value *ucontrol)
+{
+	struct soc_mixer_control *mc = (struct soc_mixer_control *)kcontrol->private_value;
+	struct snd_soc_component *component = snd_soc_kcontrol_component(kcontrol);
+	struct x9250 *x9250 = snd_soc_component_get_drvdata(component);
+	int min = mc->min;
+	int max = mc->max;
+	unsigned int mask = (1 << fls(max)) - 1;
+	unsigned int invert = mc->invert;
+	unsigned int val;
+	int ret;
+	u8 wcr;
+	u8 tmp;
+
+	wcr = mc->reg;
+	if (wcr > 4)
+		return -EINVAL;
+
+	val = ucontrol->value.integer.value[0];
+	if (val < 0)
+		return -EINVAL;
+	if (val > max - min)
+		return -EINVAL;
+
+	val = (val + min) & mask;
+	if (invert)
+		val = max - val;
+
+	ret = x9250_read8(x9250, X9250_CMD_RD_WCR(wcr), &tmp);
+	if (ret)
+		return ret;
+
+	if (tmp == val)
+		return 0;
+
+	ret = x9250_write8(x9250, X9250_CMD_WR_WCR(wcr), val);
+	if (ret)
+		return ret;
+
+	return 1; /* The value changed */
+}
+
+static const struct snd_kcontrol_new x9250_controls_std[] = {
+	SOC_SINGLE_EXT("CMD0", 0, 0, 255, 0, x8250_kctrl_cmd_get, x8250_kctrl_cmd_put),
+	SOC_SINGLE_EXT("CMD1", 1, 0, 255, 0, x8250_kctrl_cmd_get, x8250_kctrl_cmd_put),
+	SOC_SINGLE_EXT("CMD2", 2, 0, 255, 0, x8250_kctrl_cmd_get, x8250_kctrl_cmd_put),
+	SOC_SINGLE_EXT("CMD3", 3, 0, 255, 0, x8250_kctrl_cmd_get, x8250_kctrl_cmd_put),
+};
+
+static const struct snd_kcontrol_new x9250_controls_inv[] = {
+	SOC_SINGLE_EXT("CMD0", 0, 0, 255, 1, x8250_kctrl_cmd_get, x8250_kctrl_cmd_put),
+	SOC_SINGLE_EXT("CMD1", 1, 0, 255, 1, x8250_kctrl_cmd_get, x8250_kctrl_cmd_put),
+	SOC_SINGLE_EXT("CMD2", 2, 0, 255, 1, x8250_kctrl_cmd_get, x8250_kctrl_cmd_put),
+	SOC_SINGLE_EXT("CMD3", 3, 0, 255, 1, x8250_kctrl_cmd_get, x8250_kctrl_cmd_put),
+};
+
+static int x9250_component_probe(struct snd_soc_component *component)
+{
+	struct x9250 *x9250 = snd_soc_component_get_drvdata(component);
+	struct snd_kcontrol_new control[X9250_NB_CHANNEL];
+	int ret;
+	u8 wcr;
+	int i;
+
+	/* Check arrays compatibility */
+	BUILD_BUG_ON(ARRAY_SIZE(x9250_controls_std) != X9250_NB_CHANNEL);
+	BUILD_BUG_ON(ARRAY_SIZE(x9250_controls_inv) != X9250_NB_CHANNEL);
+	BUILD_BUG_ON(sizeof(control[0]) != sizeof(x9250_controls_std[0]));
+	BUILD_BUG_ON(sizeof(control[0]) != sizeof(x9250_controls_inv[0]));
+
+	for (i = 0; i < X9250_NB_CHANNEL; i++) {
+		if (x9250->cmd_inv & (1 << i)) {
+			wcr = 0xff;
+			memcpy(&control[i], &x9250_controls_inv[i], sizeof(control[i]));
+		} else {
+			wcr = 0x00;
+			memcpy(&control[i], &x9250_controls_std[i], sizeof(control[i]));
+		}
+		ret = x9250_write8(x9250, X9250_CMD_WR_WCR(i), wcr);
+		if (ret)
+			return ret;
+	}
+
+	return snd_soc_add_component_controls(component, control, ARRAY_SIZE(control));
+}
+
+static const struct snd_soc_component_driver x9250_component_driver = {
+	.probe			= x9250_component_probe,
+	.dapm_widgets		= x9250_dapm_widgets,
+	.num_dapm_widgets	= ARRAY_SIZE(x9250_dapm_widgets),
+	.dapm_routes		= x9250_dapm_routes,
+	.num_dapm_routes	= ARRAY_SIZE(x9250_dapm_routes),
+};
+
+static int x9250_spi_probe(struct spi_device *spi)
+{
+	struct x9250 *x9250;
+	int ret;
+
+	spi->bits_per_word = 8;
+	ret = spi_setup(spi);
+	if (ret < 0)
+		return ret;
+
+	x9250 = devm_kzalloc(&spi->dev, sizeof(*x9250), GFP_KERNEL);
+	if (x9250 == NULL)
+		return -ENOMEM;
+
+	x9250->spi = spi;
+
+	x9250->cmd_inv = 0;
+	if (of_property_read_bool(spi->dev.of_node, "renesas,cmd0-invert"))
+		x9250->cmd_inv |= (1 << 0);
+	if (of_property_read_bool(spi->dev.of_node, "renesas,cmd1-invert"))
+		x9250->cmd_inv |= (1 << 1);
+	if (of_property_read_bool(spi->dev.of_node, "renesas,cmd2-invert"))
+		x9250->cmd_inv |= (1 << 2);
+	if (of_property_read_bool(spi->dev.of_node, "renesas,cmd3-invert"))
+		x9250->cmd_inv |= (1 << 3);
+
+	spi_set_drvdata(spi, x9250);
+
+	return devm_snd_soc_register_component(&spi->dev, &x9250_component_driver,
+					       NULL, 0);
+}
+
+static const struct of_device_id x9250_of_match[] = {
+	{ .compatible = "renesas,x9250", },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, x9250_of_match);
+
+static const struct spi_device_id x9250_id_table[] = {
+	{ "x9250", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(spi, x9250_id_table);
+
+static struct spi_driver x9250_spi_driver = {
+	.driver  = {
+		.name   = "x9250",
+		.of_match_table = x9250_of_match,
+	},
+	.id_table = x9250_id_table,
+	.probe  = x9250_spi_probe,
+};
+
+module_spi_driver(x9250_spi_driver);
+
+MODULE_AUTHOR("Herve Codina <herve.codina@bootlin.com>");
+MODULE_DESCRIPTION("X9250 ALSA SoC driver");
+MODULE_LICENSE("GPL");
-- 
2.39.0

[PATCH 3/3] MAINTAINERS: add the Renesas X9250 ASoC entry

[Herve Codina]

After contributing the driver, add myself as the maintainer for the
Renesas X9250 ASoC driver.

Signed-off-by: Herve Codina <herve.codina@bootlin.com>
---
 MAINTAINERS | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index 31115a7e01c1..cd22e8e06561 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -17905,6 +17905,13 @@ S:	Maintained
 F:	Documentation/devicetree/bindings/clock/renesas,versaclock7.yaml
 F:	drivers/clk/clk-versaclock7.c
 
+RENESAS X9250 ASoC DRIVER
+M:	Herve Codina <herve.codina@bootlin.com>
+L:	alsa-devel@alsa-project.org (moderated for non-subscribers)
+S:	Maintained
+F:	Documentation/devicetree/bindings/sound/renesas,x9250.yaml
+F:	sound/soc/codecs/x9250.c
+
 RESET CONTROLLER FRAMEWORK
 M:	Philipp Zabel <p.zabel@pengutronix.de>
 S:	Maintained
-- 
2.39.0

Re: [PATCH 2/3] ASoC: codecs: Add support for the Renesas X9250 potentiometers

[Mark Brown]

[-- Attachment #1: Type: text/plain, Size: 820 bytes --]

On Fri, Feb 03, 2023 at 12:14:21PM +0100, Herve Codina wrote:

> +static const struct snd_kcontrol_new x9250_controls_std[] = {
> +	SOC_SINGLE_EXT("CMD0", 0, 0, 255, 0, x8250_kctrl_cmd_get, x8250_kctrl_cmd_put),
> +	SOC_SINGLE_EXT("CMD1", 1, 0, 255, 0, x8250_kctrl_cmd_get, x8250_kctrl_cmd_put),
> +	SOC_SINGLE_EXT("CMD2", 2, 0, 255, 0, x8250_kctrl_cmd_get, x8250_kctrl_cmd_put),
> +	SOC_SINGLE_EXT("CMD3", 3, 0, 255, 0, x8250_kctrl_cmd_get, x8250_kctrl_cmd_put),
> +};

These control names feel a bit icky but given that they have board
specific functions I don't see a way to sensibly rewrite them.  However
I do wonder if we might be better off having this as an IIO driver and
having a binding that lets us import IIO outputs into sound cards - I'm
guessing there are other non-audio applications for this hardware?

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 488 bytes --]

Re: [PATCH 1/3] dt-bindings: sound: Add the Renesas X9250 potentiometers

[Rob Herring]

On Fri, Feb 03, 2023 at 12:14:20PM +0100, Herve Codina wrote:
> The Renesas X9250 is a quad digitally controlled potentiometers.
> 
> Signed-off-by: Herve Codina <herve.codina@bootlin.com>
> ---
>  .../bindings/sound/renesas,x9250.yaml         | 60 +++++++++++++++++++
>  1 file changed, 60 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/sound/renesas,x9250.yaml
> 
> diff --git a/Documentation/devicetree/bindings/sound/renesas,x9250.yaml b/Documentation/devicetree/bindings/sound/renesas,x9250.yaml
> new file mode 100644
> index 000000000000..ad29ef465a18
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/sound/renesas,x9250.yaml
> @@ -0,0 +1,60 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/sound/renesas,x9250.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Renesas X9250 quad potentiometers
> +
> +maintainers:
> +  - Herve Codina <herve.codina@bootlin.com>
> +
> +description: |
> +  The Renesas X9250 is a quad digitally controlled potentiometers.

...is a chip with quad...

> +
> +  In the audio path, it can be present on amplifiers designs and it can be used
> +  in ALSA as an auxiliary audio device to control these amplifiers.

ALSA? Linux details should not be in bindings.

> +
> +allOf:
> +  - $ref: /schemas/spi/spi-peripheral-props.yaml
> +  - $ref: dai-common.yaml#
> +
> +properties:
> +  compatible:
> +    const: renesas,x9250
> +
> +  reg:
> +    description:
> +      SPI device address.
> +    maxItems: 1
> +
> +  spi-max-frequency:
> +    maximum: 2000000
> +
> +patternProperties:
> +  "^renesas,cmd[0-3]-invert$":
> +    description:
> +      The related command is inverted meaning that the minimum command value
> +      set the wiper to Rh and the maximum command value set the wiper to Rl.
> +      Without this property, the minimum command value set the wiper to Rl and
> +      the maximum to Rh.
> +    type: boolean
> +
> +required:
> +  - compatible
> +  - reg
> +
> +unevaluatedProperties: false
> +
> +examples:
> +  - |
> +    spi {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +        x9250@0 {
> +            compatible = "renesas,x9250";
> +            reg = <0>;
> +            spi-max-frequency = <2000000>;
> +            renesas,cmd3-invert;
> +        };
> +    };
> -- 
> 2.39.0
>