[PATCH v3 0/2] Enable audio support for J721S2 EVM

[PATCH v3 0/2] Enable audio support for J721S2 EVM

[Moteen Shah]

This patch series, adds support for analog audio on J721S2 EVM using
device tree overlays.

Earlier version of the patchset sent upstream[0] was rejected as
its dependency[1], which resolves the DTBS check errors introduced
by [0] also got rejected on the grounds of ABI breakage.

Another solution to fix the DTBS check errors introduced by [0] is
to modify the ti,j721e-system-controller.yaml binding to allow
audio-refclk as clock-controller child. This is done in the first
patch of this series.

Changes since v2:
Link to v2: https://lore.kernel.org/all/20260205130707.2033197-1-m-shah@ti.com/

- Fix Makefile entries to follow alphabetical ordering
- Update model string from "j721e-cpb" to "j721s2-cpb"
- Fix gpio-line-names typo: "UBS926_PWR_SW_CNTRL" -> "UB926_PWR_SW_CNTRL"

Changes since v1:
Link to v1: https://lore.kernel.org/all/20260112104536.83309-1-m-shah@ti.com/

- Convert the changes to an overlay
- Enumerate the I2C mux used
- Remove CANUART_MUX_SEL1 gpio hog
- Fix typos
- Add gpio-line-names
- Fix commit message to showcase the right idle-state for muxes
- Carry review from Rob and Hari

Test log: https://gist.github.com/Jamm02/4d4c00bf88fa76cddae6319124341c53

[0]: https://lore.kernel.org/linux-arm-kernel/20250604104656.38752-1-j-choudhary@ti.com/
[1]: https://lore.kernel.org/all/20250603095609.33569-4-j-choudhary@ti.com/

Jayesh Choudhary (1):
  arm64: dts: ti: Add audio overlay for k3-j721s2-evm

Moteen Shah (1):
  ti,j721e-system-controller.yaml: Allow audio-refclk as
    clock-controller child

 .../soc/ti/ti,j721e-system-controller.yaml    |   6 +-
 arch/arm64/boot/dts/ti/Makefile               |   4 +
 .../boot/dts/ti/k3-j721s2-evm-audio.dtso      | 161 ++++++++++++++++++
 3 files changed, 169 insertions(+), 2 deletions(-)
 create mode 100644 arch/arm64/boot/dts/ti/k3-j721s2-evm-audio.dtso

-- 
2.34.1

[PATCH v3 1/2] ti,j721e-system-controller.yaml: Allow audio-refclk as clock-controller child

[Moteen Shah]

The ti,j721e-system-controller binding currently only allows
clock-controller@ child nodes to reference the ti,am654-ehrpwm-tbclk
schema. However, the system controller on J721S2 also contains audio
reference clock controllers (ti,am62-audio-refclk) that use the same
clock-controller@XXXX naming pattern.

Hence, extend the clock-controller pattern to accept either ehrpwm-tbclk
or audio-refclk schemas using a oneOf constraint.

Signed-off-by: Moteen Shah <m-shah@ti.com>
---
 .../bindings/soc/ti/ti,j721e-system-controller.yaml         | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/soc/ti/ti,j721e-system-controller.yaml b/Documentation/devicetree/bindings/soc/ti/ti,j721e-system-controller.yaml
index f3bd0be3b279..d5d84a8f1257 100644
--- a/Documentation/devicetree/bindings/soc/ti/ti,j721e-system-controller.yaml
+++ b/Documentation/devicetree/bindings/soc/ti/ti,j721e-system-controller.yaml
@@ -53,9 +53,11 @@ patternProperties:
 
   "^clock-controller@[0-9a-f]+$":
     type: object
-    $ref: /schemas/clock/ti,am654-ehrpwm-tbclk.yaml#
+    oneOf:
+      - $ref: /schemas/clock/ti,am654-ehrpwm-tbclk.yaml#
+      - $ref: /schemas/clock/ti,am62-audio-refclk.yaml#
     description:
-      Clock provider for TI EHRPWM nodes.
+      Clock provider for TI EHRPWM or Audio Reference Clock nodes.
 
   "phy@[0-9a-f]+$":
     type: object
-- 
2.34.1

[PATCH v3 2/2] arm64: dts: ti: Add audio overlay for k3-j721s2-evm

[Moteen Shah]

From: Jayesh Choudhary <j-choudhary@ti.com>

Add device tree overlay to enable analog audio support on J721S2-EVM
using PCM3168A codec connected to McASP4 serializers.

- Add nodes for sound-card, audio codec, I2C3 and McASP4
- Add pinmux for I2C3, McASP4, AUDIO_EXT_REFCLK1 and WKUP_GPIO_0
- Add GPIO expander (TCA6408) for codec control
- Add GPIO hogs to route I2C3 lines and McASP serializers
- Set idle-state to 0 in mux0 and mux1 for McASP signal routing

Signed-off-by: Jayesh Choudhary <j-choudhary@ti.com>
Co-developed-by: Moteen Shah <m-shah@ti.com>
Signed-off-by: Moteen Shah <m-shah@ti.com>
---
 arch/arm64/boot/dts/ti/Makefile               |   4 +
 .../boot/dts/ti/k3-j721s2-evm-audio.dtso      | 161 ++++++++++++++++++
 2 files changed, 165 insertions(+)
 create mode 100644 arch/arm64/boot/dts/ti/k3-j721s2-evm-audio.dtso

diff --git a/arch/arm64/boot/dts/ti/Makefile b/arch/arm64/boot/dts/ti/Makefile
index ba01a929e06f..17048f2f5043 100644
--- a/arch/arm64/boot/dts/ti/Makefile
+++ b/arch/arm64/boot/dts/ti/Makefile
@@ -138,6 +138,7 @@ dtb-$(CONFIG_ARCH_K3) += k3-j721s2-common-proc-board.dtb
 dtb-$(CONFIG_ARCH_K3) += k3-j721s2-evm-gesi-exp-board.dtbo
 k3-j721s2-evm-dtbs := k3-j721s2-common-proc-board.dtb k3-j721s2-evm-gesi-exp-board.dtbo
 dtb-$(CONFIG_ARCH_K3) += k3-j721s2-evm.dtb
+dtb-$(CONFIG_ARCH_K3) += k3-j721s2-evm-audio.dtbo
 dtb-$(CONFIG_ARCH_K3) += k3-j721s2-evm-pcie1-ep.dtbo
 dtb-$(CONFIG_ARCH_K3) += k3-j721s2-evm-usb0-type-a.dtbo
 
@@ -264,6 +265,8 @@ k3-j721e-evm-pcie1-ep-dtbs := k3-j721e-common-proc-board.dtb \
 	k3-j721e-evm-pcie1-ep.dtbo
 k3-j721e-sk-csi2-dual-imx219-dtbs := k3-j721e-sk.dtb \
 	k3-j721e-sk-csi2-dual-imx219.dtbo
+k3-j721s2-evm-audio-dtbs := k3-j721s2-common-proc-board.dtb \
+	k3-j721s2-evm-audio.dtbo
 k3-j721s2-evm-pcie1-ep-dtbs := k3-j721s2-common-proc-board.dtb \
 	k3-j721s2-evm-pcie1-ep.dtbo
 k3-j721s2-evm-usb0-type-a-dtbs := k3-j721s2-common-proc-board.dtb \
@@ -328,6 +331,7 @@ dtb- += k3-am625-beagleplay-csi2-ov5640.dtb \
 	k3-j721e-evm-pcie0-ep.dtb \
 	k3-j721e-evm-pcie1-ep.dtb \
 	k3-j721e-sk-csi2-dual-imx219.dtb \
+	k3-j721s2-evm-audio.dtb \
 	k3-j721s2-evm-pcie1-ep.dtb \
 	k3-j721s2-evm-usb0-type-a.dtb \
 	k3-j722s-evm-csi2-quad-rpi-cam-imx219.dtb \
diff --git a/arch/arm64/boot/dts/ti/k3-j721s2-evm-audio.dtso b/arch/arm64/boot/dts/ti/k3-j721s2-evm-audio.dtso
new file mode 100644
index 000000000000..2a3ff1cfc650
--- /dev/null
+++ b/arch/arm64/boot/dts/ti/k3-j721s2-evm-audio.dtso
@@ -0,0 +1,161 @@
+// SPDX-License-Identifier: GPL-2.0-only OR MIT
+/*
+ * Device Tree Overlay for J721S2 Audio Support
+ *
+ * Copyright (C) 2026 Texas Instruments Incorporated - https://www.ti.com/
+ */
+
+/dts-v1/;
+/plugin/;
+
+#include <dt-bindings/gpio/gpio.h>
+
+#include "k3-pinctrl.h"
+
+&{/} {
+	codec_audio: sound {
+		compatible = "ti,j7200-cpb-audio";
+		model = "j721s2-cpb";
+
+		ti,cpb-mcasp = <&mcasp4>;
+		ti,cpb-codec = <&pcm3168a_1>;
+
+		clocks = <&k3_clks 213 0>, <&k3_clks 213 1>,
+			 <&k3_clks 157 299>, <&k3_clks 157 328>;
+		clock-names = "cpb-mcasp-auxclk", "cpb-mcasp-auxclk-48000",
+			      "cpb-codec-scki", "cpb-codec-scki-48000";
+	};
+
+	i2c_mux: mux-controller-2 {
+		compatible = "gpio-mux";
+		#mux-state-cells = <1>;
+		mux-gpios = <&wkup_gpio0 54 GPIO_ACTIVE_HIGH>;
+		idle-state = <1>;
+		pinctrl-names = "default";
+		pinctrl-0 = <&main_i2c3_mux_pins_default>;
+	};
+};
+
+&main_pmx0 {
+	mcasp4_pins_default: mcasp4-default-pins {
+		pinctrl-single,pins = <
+			J721S2_IOPAD(0x0c8, PIN_OUTPUT_PULLDOWN, 1) /* (AD28) MCASP4_ACLKX */
+			J721S2_IOPAD(0x06c, PIN_OUTPUT_PULLDOWN, 1) /* (V26) MCASP4_AFSX */
+			J721S2_IOPAD(0x068, PIN_INPUT_PULLDOWN, 1) /* (U28) MCASP4_AXR1 */
+			J721S2_IOPAD(0x0c4, PIN_OUTPUT_PULLDOWN, 1) /* (AB26) MCASP4_AXR2 */
+			J721S2_IOPAD(0x070, PIN_OUTPUT_PULLDOWN, 1) /* (R27) MCASP4_AXR3 */
+		>;
+	};
+
+	audio_ext_refclk1_pins_default: audio-ext-refclk1-default-pins {
+		pinctrl-single,pins = <
+			J721S2_IOPAD(0x078, PIN_OUTPUT, 1) /* (Y25) MCAN2_RX.AUDIO_EXT_REFCLK1 */
+		>;
+	};
+};
+
+&wkup_pmx2 {
+	main_i2c3_mux_pins_default: main-i2c3-mux-default-pins {
+		pinctrl-single,pins = <
+			J721S2_WKUP_IOPAD(0x038, PIN_OUTPUT, 7) /* (B27) WKUP_GPIO0_54 */
+		>;
+	};
+};
+
+&exp2 {
+	p09-hog {
+		/* P09 - MCASP/TRACE_MUX_S0 */
+		gpio-hog;
+		gpios = <9 GPIO_ACTIVE_HIGH>;
+		output-low;
+		line-name = "MCASP/TRACE_MUX_S0";
+	};
+
+	p10-hog {
+		/* P10 - MCASP/TRACE_MUX_S1 */
+		gpio-hog;
+		gpios = <10 GPIO_ACTIVE_HIGH>;
+		output-high;
+		line-name = "MCASP/TRACE_MUX_S1";
+	};
+};
+
+&mux0 {
+	idle-state = <0>;
+};
+
+&mux1 {
+	idle-state = <0>;
+};
+
+&scm_conf {
+	#address-cells = <1>;
+	#size-cells = <1>;
+
+	audio_refclk1: clock-controller@42e4 {
+		compatible = "ti,am62-audio-refclk";
+		reg = <0x42e4 0x4>;
+		clocks = <&k3_clks 157 299>;
+		assigned-clocks = <&k3_clks 157 299>;
+		assigned-clock-parents = <&k3_clks 157 328>;
+		#clock-cells = <0>;
+	};
+};
+
+&k3_clks {
+	/* Configure AUDIO_EXT_REFCLK1 pin as output */
+	pinctrl-names = "default";
+	pinctrl-0 = <&audio_ext_refclk1_pins_default>;
+};
+
+&main_i2c3 {
+	status = "okay";
+	pinctrl-names = "default";
+	pinctrl-0 = <&main_i2c3_pins_default>;
+	clock-frequency = <400000>;
+	mux-states = <&i2c_mux 1>;
+	#address-cells = <1>;
+	#size-cells = <0>;
+
+	exp3: gpio@20 {
+		compatible = "ti,tca6408";
+		reg = <0x20>;
+		gpio-controller;
+		#gpio-cells = <2>;
+		gpio-line-names = "CODEC_RSTZ", "CODEC_SPARE1",
+				  "UB926_RESETN", "UB926_LOCK",
+				  "UB926_PWR_SW_CNTRL", "UB926_TUNER_RESET",
+				  "UB926_GPIO_SPARE";
+	};
+
+	pcm3168a_1: audio-codec@44 {
+		compatible = "ti,pcm3168a";
+		reg = <0x44>;
+		#sound-dai-cells = <1>;
+		reset-gpios = <&exp3 0 GPIO_ACTIVE_LOW>;
+		clocks = <&audio_refclk1>;
+		clock-names = "scki";
+		VDD1-supply = <&vsys_3v3>;
+		VDD2-supply = <&vsys_3v3>;
+		VCCAD1-supply = <&vsys_5v0>;
+		VCCAD2-supply = <&vsys_5v0>;
+		VCCDA1-supply = <&vsys_5v0>;
+		VCCDA2-supply = <&vsys_5v0>;
+	};
+};
+
+&mcasp4 {
+	status = "okay";
+	#sound-dai-cells = <0>;
+	pinctrl-names = "default";
+	pinctrl-0 = <&mcasp4_pins_default>;
+	op-mode = <0>;          /* MCASP_IIS_MODE */
+	tdm-slots = <2>;
+	auxclk-fs-ratio = <256>;
+	serial-dir = <	/* 0: INACTIVE, 1: TX, 2: RX */
+		0 2 1 1
+		0 0 0 0
+		0 0 0 0
+		0 0 0 0
+	>;
+};
-- 
2.34.1

Re: [PATCH v3 1/2] ti,j721e-system-controller.yaml: Allow audio-refclk as clock-controller child

[Krzysztof Kozlowski]

On Mon, Mar 30, 2026 at 03:14:58PM +0530, Moteen Shah wrote:
> The ti,j721e-system-controller binding currently only allows
> clock-controller@ child nodes to reference the ti,am654-ehrpwm-tbclk
> schema. However, the system controller on J721S2 also contains audio

J721S2 or AM62?

> reference clock controllers (ti,am62-audio-refclk) that use the same
> clock-controller@XXXX naming pattern.
> 
> Hence, extend the clock-controller pattern to accept either ehrpwm-tbclk
> or audio-refclk schemas using a oneOf constraint.
> 
> Signed-off-by: Moteen Shah <m-shah@ti.com>
> ---
>  .../bindings/soc/ti/ti,j721e-system-controller.yaml         | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/soc/ti/ti,j721e-system-controller.yaml b/Documentation/devicetree/bindings/soc/ti/ti,j721e-system-controller.yaml
> index f3bd0be3b279..d5d84a8f1257 100644
> --- a/Documentation/devicetree/bindings/soc/ti/ti,j721e-system-controller.yaml
> +++ b/Documentation/devicetree/bindings/soc/ti/ti,j721e-system-controller.yaml
> @@ -53,9 +53,11 @@ patternProperties:
>  
>    "^clock-controller@[0-9a-f]+$":
>      type: object
> -    $ref: /schemas/clock/ti,am654-ehrpwm-tbclk.yaml#
> +    oneOf:
> +      - $ref: /schemas/clock/ti,am654-ehrpwm-tbclk.yaml#
> +      - $ref: /schemas/clock/ti,am62-audio-refclk.yaml#

Alphanumerical order.

There is no ti,am62 in the top level compatibles, so why am62 is here?
Top level has j721s2 but this ti,am62-audio-refclk.yaml only am62.

Best regards,
Krzysztof

Re: [PATCH v3 2/2] arm64: dts: ti: Add audio overlay for k3-j721s2-evm

[Krzysztof Kozlowski]

On Mon, Mar 30, 2026 at 03:14:59PM +0530, Moteen Shah wrote:
> +	p10-hog {
> +		/* P10 - MCASP/TRACE_MUX_S1 */
> +		gpio-hog;
> +		gpios = <10 GPIO_ACTIVE_HIGH>;
> +		output-high;
> +		line-name = "MCASP/TRACE_MUX_S1";
> +	};
> +};
> +
> +&mux0 {
> +	idle-state = <0>;
> +};
> +
> +&mux1 {
> +	idle-state = <0>;
> +};
> +
> +&scm_conf {
> +	#address-cells = <1>;
> +	#size-cells = <1>;
> +
> +	audio_refclk1: clock-controller@42e4 {
> +		compatible = "ti,am62-audio-refclk";

there is no am62 compatible or DTSI include in the parent SoC file, so
am62n seems to be completely different device than j721s2.

Why does am62b appear here in this context?

Best regards,
Krzysztof

Re: [PATCH v3 1/2] ti,j721e-system-controller.yaml: Allow audio-refclk as clock-controller child

[Moteen Shah]

Hey Krzysztof,

On 31/03/26 12:39, Krzysztof Kozlowski wrote:
> On Mon, Mar 30, 2026 at 03:14:58PM +0530, Moteen Shah wrote:
>> The ti,j721e-system-controller binding currently only allows
>> clock-controller@ child nodes to reference the ti,am654-ehrpwm-tbclk
>> schema. However, the system controller on J721S2 also contains audio
> J721S2 or AM62?
>
>> reference clock controllers (ti,am62-audio-refclk) that use the same
>> clock-controller@XXXX naming pattern.
>>
>> Hence, extend the clock-controller pattern to accept either ehrpwm-tbclk
>> or audio-refclk schemas using a oneOf constraint.
>>
>> Signed-off-by: Moteen Shah <m-shah@ti.com>
>> ---
>>   .../bindings/soc/ti/ti,j721e-system-controller.yaml         | 6 ++++--
>>   1 file changed, 4 insertions(+), 2 deletions(-)
>>
>> diff --git a/Documentation/devicetree/bindings/soc/ti/ti,j721e-system-controller.yaml b/Documentation/devicetree/bindings/soc/ti/ti,j721e-system-controller.yaml
>> index f3bd0be3b279..d5d84a8f1257 100644
>> --- a/Documentation/devicetree/bindings/soc/ti/ti,j721e-system-controller.yaml
>> +++ b/Documentation/devicetree/bindings/soc/ti/ti,j721e-system-controller.yaml
>> @@ -53,9 +53,11 @@ patternProperties:
>>   
>>     "^clock-controller@[0-9a-f]+$":
>>       type: object
>> -    $ref: /schemas/clock/ti,am654-ehrpwm-tbclk.yaml#
>> +    oneOf:
>> +      - $ref: /schemas/clock/ti,am654-ehrpwm-tbclk.yaml#
>> +      - $ref: /schemas/clock/ti,am62-audio-refclk.yaml#
> Alphanumerical order.
>
> There is no ti,am62 in the top level compatibles, so why am62 is here?
> Top level has j721s2 but this ti,am62-audio-refclk.yaml only am62.
>
> Best regards,
> Krzysztof

The "ti,am62-audio-refclk" compatible refers to a shared audio reference 
clock IP block that was first introduced/named on AM62 but is present on 
other TI K3 SoCs as well, including J721S2. The compatible string 
identifies the IP block, not the SoC family.

This is already an established pattern — 
k3-j784s4-j742s2-main-common.dtsi uses the same compatible for the 
J784S4/J742S2 audio refclk node.

The ti,j721e-system-controller.yaml binding (which covers 
ti,j721s2-system-controller) already lists ti,am62-audio-refclk as an 
allowed clock-controller child, which was updated in patch 1/2 of this 
series to make room for this node.

Best regards,
Moteen Shah

Re: [PATCH v3 1/2] ti,j721e-system-controller.yaml: Allow audio-refclk as clock-controller child

[Krzysztof Kozlowski]

On 07/04/2026 07:46, Moteen Shah wrote:
> Hey Krzysztof,
> 
> On 31/03/26 12:39, Krzysztof Kozlowski wrote:
>> On Mon, Mar 30, 2026 at 03:14:58PM +0530, Moteen Shah wrote:
>>> The ti,j721e-system-controller binding currently only allows
>>> clock-controller@ child nodes to reference the ti,am654-ehrpwm-tbclk
>>> schema. However, the system controller on J721S2 also contains audio
>> J721S2 or AM62?
>>
>>> reference clock controllers (ti,am62-audio-refclk) that use the same
>>> clock-controller@XXXX naming pattern.
>>>
>>> Hence, extend the clock-controller pattern to accept either ehrpwm-tbclk
>>> or audio-refclk schemas using a oneOf constraint.
>>>
>>> Signed-off-by: Moteen Shah <m-shah@ti.com>
>>> ---
>>>   .../bindings/soc/ti/ti,j721e-system-controller.yaml         | 6 ++++--
>>>   1 file changed, 4 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/Documentation/devicetree/bindings/soc/ti/ti,j721e-system-controller.yaml b/Documentation/devicetree/bindings/soc/ti/ti,j721e-system-controller.yaml
>>> index f3bd0be3b279..d5d84a8f1257 100644
>>> --- a/Documentation/devicetree/bindings/soc/ti/ti,j721e-system-controller.yaml
>>> +++ b/Documentation/devicetree/bindings/soc/ti/ti,j721e-system-controller.yaml
>>> @@ -53,9 +53,11 @@ patternProperties:
>>>   
>>>     "^clock-controller@[0-9a-f]+$":
>>>       type: object
>>> -    $ref: /schemas/clock/ti,am654-ehrpwm-tbclk.yaml#
>>> +    oneOf:
>>> +      - $ref: /schemas/clock/ti,am654-ehrpwm-tbclk.yaml#
>>> +      - $ref: /schemas/clock/ti,am62-audio-refclk.yaml#
>> Alphanumerical order.
>>
>> There is no ti,am62 in the top level compatibles, so why am62 is here?
>> Top level has j721s2 but this ti,am62-audio-refclk.yaml only am62.
>>
>> Best regards,
>> Krzysztof
> 
> The "ti,am62-audio-refclk" compatible refers to a shared audio reference 
> clock IP block that was first introduced/named on AM62 but is present on 
> other TI K3 SoCs as well, including J721S2. The compatible string 
> identifies the IP block, not the SoC family.
> 
> This is already an established pattern — 
> k3-j784s4-j742s2-main-common.dtsi uses the same compatible for the 
> J784S4/J742S2 audio refclk node.

Please read carefully writing-bindings doc.


Best regards,
Krzysztof