[PATCH RFC] dt-bindings: sound: Convert cirrus,cs35l36 to DT schema

From: David Heidelberg via B4 Relay

Date: Thu Jun 18 2026 - 10:33:49 EST

From: David Heidelberg <david@xxxxxxx>

Convert CS35L36 Speaker Amplifier.

Changes:
- maintainers email to the generic Cirrus email
- Both the codec and downstream worked just fine without
VP-supply provided. Align with datasheet for similar models.
- add dai-common.yaml to cover for '#sound-dai-cells',
'sound-name-prefix'

Co-developed-by: Rob Herring (Arm) <robh@xxxxxxxxxx>
Signed-off-by: Rob Herring (Arm) <robh@xxxxxxxxxx>
Signed-off-by: David Heidelberg <david@xxxxxxx>
---
Relevant for Pixel 3 / 3XL / 4.
---
.../devicetree/bindings/sound/cirrus,cs35l36.yaml | 224 +++++++++++++++++++++
.../devicetree/bindings/sound/cs35l36.txt | 168 ----------------
2 files changed, 224 insertions(+), 168 deletions(-)

diff --git a/Documentation/devicetree/bindings/sound/cirrus,cs35l36.yaml b/Documentation/devicetree/bindings/sound/cirrus,cs35l36.yaml
new file mode 100644
index 0000000000000..af0acaaefb68e
--- /dev/null
+++ b/Documentation/devicetree/bindings/sound/cirrus,cs35l36.yaml
@@ -0,0 +1,224 @@
+# SPDX-License-Identifier: GPL-2.0-only
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/cirrus,cs35l36.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Cirrus Logic CS35L36 Speaker Amplifier
+
+maintainers:
+ - patches@xxxxxxxxxxxxxxxxxxxxx
+ - Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
+
+description: |
+ CS35L36 is a boosted mono Class D amplifier
+
+allOf:
+ - $ref: /schemas/sound/dai-common.yaml#
+
+properties:
+ compatible:
+ enum:
+ - cirrus,cs35l36
+
+ reg:
+ maxItems: 1
+
+ interrupts:
+ maxItems: 1
+
+ VA-supply:
+ description: Voltage regulator of analog internal section
+
+ VP-supply:
+ description: Voltage regulator of boost converter
+
+ reset-gpios:
+ maxItems: 1
+
+ cirrus,boost-ctl-millivolt:
+ description: Boost converter output voltage in millivolts (step 50)
+ $ref: /schemas/types.yaml#/definitions/uint32
+ minimum: 2550
+ maximum: 12000
+
+ cirrus,boost-peak-milliamp:
+ description: Boost-converter peak current limit in mA (step 50)
+ $ref: /schemas/types.yaml#/definitions/uint32
+ default: 4500
+ minimum: 1600
+ maximum: 4500
+
+ cirrus,boost-ind-nanohenry:
+ description: Initial inductor estimation reference value in nanohenry (1000=1μH, 1200=1.2μH)
+ $ref: /schemas/types.yaml#/definitions/uint32
+ default: 1000
+
+ cirrus,multi-amp-mode:
+ description: Hi-Z ASP port when more than one amplifier in system.
+ type: boolean
+
+ cirrus,boost-ctl-select:
+ description: Boost converter control source selection
+ $ref: /schemas/types.yaml#/definitions/uint32
+ default: 0x01
+ enum:
+ - 0x00 # Control Port
+ - 0x01 # Class
+ - 0x10 # Sync
+
+ cirrus,amp-pcm-inv:
+ description: Invert incoming PCM data when true.
+ type: boolean
+
+ cirrus,imon-pol-inv:
+ description: Invert polarity of outbound IMON feedback when true.
+ type: boolean
+
+ cirrus,vmon-pol-inv:
+ description: Invert polarity of outbound VMON feedback when true.
+ type: boolean
+
+ cirrus,dcm-mode-enable:
+ description: Enable boost converter automatic Discontinuous Conduction Mode.
+ type: boolean
+
+ cirrus,weak-fet-disable:
+ description: Reduce output driver strength in Weak-FET Drive Mode when true.
+ type: boolean
+
+ cirrus,classh-wk-fet-delay:
+ description: Weak-FET entry delay in ms
+ $ref: /schemas/types.yaml#/definitions/uint32
+ default: 100
+ enum:
+ - 0 # 0
+ - 1 # 5
+ - 2 # 10
+ - 3 # 50
+ - 4 # 100
+ - 5 # 200
+ - 6 # 500
+ - 7 # 1000
+
+ cirrus,classh-weak-fet-thld-millivolt:
+ description: Weak-FET drive threshold in mV
+ $ref: /schemas/types.yaml#/definitions/uint32
+ enum: [50, 100, 150, 200, 250, 300, 350, 400, 450, 500, 550, 600, 650, 700]
+
+ cirrus,temp-warn-threshold:
+ description: Overtemperature warning threshold
+ $ref: /schemas/types.yaml#/definitions/uint32
+ default: 2
+ enum:
+ - 0 # 105°C
+ - 1 # 115°C
+ - 2 # 125°C
+ - 3 # 135°C
+
+ cirrus,irq-drive-select:
+ description: Interrupt output driver type
+ $ref: /schemas/types.yaml#/definitions/uint32
+ default: 1
+ enum:
+ - 0 # open-drain
+ - 1 # push-pull
+
+ cirrus,irq-gpio-select:
+ description: Programmable IRQ pin selection
+ $ref: /schemas/types.yaml#/definitions/uint32
+ enum:
+ - 0 # PDM_DATA/SWIRE_SD/INT
+ - 1 # GPIO
+
+ cirrus,vpbr-config:
+ description: Brownout prevention configuration sub-node
+ type: object
+ additionalProperties: false
+
+ properties:
+ cirrus,vpbr-en:
+ description: VBST brownout prevention enable
+ $ref: /schemas/types.yaml#/definitions/uint32
+ default: 0
+ enum:
+ - 0 # disabled
+ - 1 # enabled
+
+ cirrus,vpbr-thld:
+ description: Initial VPBR threshold voltage
+ $ref: /schemas/types.yaml#/definitions/uint32
+
+ cirrus,vpbr-atk-rate:
+ description: Attenuation attack step rate
+ $ref: /schemas/types.yaml#/definitions/uint32
+
+ cirrus,vpbr-atk-vol:
+ description: VP brownout prevention step size
+ $ref: /schemas/types.yaml#/definitions/uint32
+
+ cirrus,vpbr-max-attn:
+ description: Maximum attenuation during VP brownout prevention
+ $ref: /schemas/types.yaml#/definitions/uint32
+
+ cirrus,vpbr-wait:
+ description: Delay between brownout clearance and attenuation release
+ $ref: /schemas/types.yaml#/definitions/uint32
+
+ cirrus,vpbr-rel-rate:
+ description: Attenuation release step rate
+ $ref: /schemas/types.yaml#/definitions/uint32
+
+ cirrus,vpbr-mute-en:
+ description: Mute audio if maximum attenuation reached
+ $ref: /schemas/types.yaml#/definitions/uint32
+
+required:
+ - compatible
+ - reg
+ - interrupts
+ - VA-supply
+
+unevaluatedProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/gpio/gpio.h>
+ #include <dt-bindings/interrupt-controller/irq.h>
+
+ i2c {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ codec@40 {
+ compatible = "cirrus,cs35l36";
+ reg = <0x40>;
+ VA-supply = <&dummy_vreg>;
+ VP-supply = <&dummy_vreg>;
+ reset-gpios = <&gpio0 54 GPIO_ACTIVE_HIGH>;
+ interrupts = <3 IRQ_TYPE_LEVEL_LOW>;
+
+ cirrus,boost-ind-nanohenry = <1000>;
+ cirrus,boost-ctl-millivolt = <10000>;
+ cirrus,boost-peak-milliamp = <4500>;
+ cirrus,boost-ctl-select = <0x00>;
+ cirrus,weak-fet-delay = <4>;
+ cirrus,weak-fet-thld = <0x01>;
+ cirrus,temp-warn-threshold = <1>;
+ cirrus,multi-amp-mode;
+ cirrus,irq-drive-select = <1>;
+ cirrus,irq-gpio-select = <0x01>;
+
+ cirrus,vpbr-config {
+ cirrus,vpbr-en = <0>;
+ cirrus,vpbr-thld = <0x05>;
+ cirrus,vpbr-atk-rate = <0x02>;
+ cirrus,vpbr-atk-vol = <0x01>;
+ cirrus,vpbr-max-attn = <0x09>;
+ cirrus,vpbr-wait = <0x01>;
+ cirrus,vpbr-rel-rate = <0x05>;
+ cirrus,vpbr-mute-en = <0x00>;
+ };
+ };
+ };
+...
diff --git a/Documentation/devicetree/bindings/sound/cs35l36.txt b/Documentation/devicetree/bindings/sound/cs35l36.txt
deleted file mode 100644
index d34117b8558e5..0000000000000
--- a/Documentation/devicetree/bindings/sound/cs35l36.txt
+++ /dev/null
@@ -1,168 +0,0 @@
-CS35L36 Speaker Amplifier
-
-Required properties:
-
- - compatible : "cirrus,cs35l36"
-
- - reg : the I2C address of the device for I2C
-
- - VA-supply, VP-supply : power supplies for the device,
- as covered in
- Documentation/devicetree/bindings/regulator/regulator.txt.
-
- - cirrus,boost-ctl-millivolt : Boost Voltage Value. Configures the boost
- converter's output voltage in mV. The range is from 2550mV to 12000mV with
- increments of 50mV.
- (Default) VP
-
- - cirrus,boost-peak-milliamp : Boost-converter peak current limit in mA.
- Configures the peak current by monitoring the current through the boost FET.
- Range starts at 1600mA and goes to a maximum of 4500mA with increments of
- 50mA.
- (Default) 4.50 Amps
-
- - cirrus,boost-ind-nanohenry : Inductor estimation LBST reference value.
- Seeds the digital boost converter's inductor estimation block with the initial
- inductance value to reference.
-
- 1000 = 1uH (Default)
- 1200 = 1.2uH
-
-Optional properties:
- - cirrus,multi-amp-mode : Boolean to determine if there are more than
- one amplifier in the system. If more than one it is best to Hi-Z the ASP
- port to prevent bus contention on the output signal
-
- - cirrus,boost-ctl-select : Boost converter control source selection.
- Selects the source of the BST_CTL target VBST voltage for the boost
- converter to generate.
- 0x00 - Control Port Value
- 0x01 - Class H Tracking (Default)
- 0x10 - MultiDevice Sync Value
-
- - cirrus,amp-pcm-inv : Boolean to determine Amplifier will invert incoming
- PCM data
-
- - cirrus,imon-pol-inv : Boolean to determine Amplifier will invert the
- polarity of outbound IMON feedback data
-
- - cirrus,vmon-pol-inv : Boolean to determine Amplifier will invert the
- polarity of outbound VMON feedback data
-
- - cirrus,dcm-mode-enable : Boost converter automatic DCM Mode enable.
- This enables the digital boost converter to operate in a low power
- (Discontinuous Conduction) mode during low loading conditions.
-
- - cirrus,weak-fet-disable : Boolean : The strength of the output drivers is
- reduced when operating in a Weak-FET Drive Mode and must not be used to drive
- a large load.
-
- - cirrus,classh-wk-fet-delay : Weak-FET entry delay. Controls the delay
- (in ms) before the Class H algorithm switches to the weak-FET voltage
- (after the audio falls and remains below the value specified in WKFET_AMP_THLD).
-
- 0 = 0ms
- 1 = 5ms
- 2 = 10ms
- 3 = 50ms
- 4 = 100ms (Default)
- 5 = 200ms
- 6 = 500ms
- 7 = 1000ms
-
- - cirrus,classh-weak-fet-thld-millivolt : Weak-FET amplifier drive threshold.
- Configures the signal threshold at which the PWM output stage enters
- weak-FET operation. The range is 50mV to 700mV in 50mV increments.
-
- - cirrus,temp-warn-threshold : Amplifier overtemperature warning threshold.
- Configures the threshold at which the overtemperature warning condition occurs.
- When the threshold is met, the overtemperature warning attenuation is applied
- and the TEMP_WARN_EINT interrupt status bit is set.
- If TEMP_WARN_MASK = 0, INTb is asserted.
-
- 0 = 105C
- 1 = 115C
- 2 = 125C (Default)
- 3 = 135C
-
- - cirrus,irq-drive-select : Selects the driver type of the selected interrupt
- output.
-
- 0 = Open-drain
- 1 = Push-pull (Default)
-
- - cirrus,irq-gpio-select : Selects the pin to serve as the programmable
- interrupt output.
-
- 0 = PDM_DATA / SWIRE_SD / INT (Default)
- 1 = GPIO
-
-Optional properties for the "cirrus,vpbr-config" Sub-node
-
- - cirrus,vpbr-en : VBST brownout prevention enable. Configures whether the
- VBST brownout prevention algorithm is enabled or disabled.
-
- 0 = VBST brownout prevention disabled (default)
- 1 = VBST brownout prevention enabled
-
- See Section 7.31.1 VPBR Config for configuration options & further details
-
- - cirrus,vpbr-thld : Initial VPBR threshold. Configures the VP brownout
- threshold voltage
-
- - cirrus,cirrus,vpbr-atk-rate : Attenuation attack step rate. Configures the
- amount delay between consecutive volume attenuation steps when a brownout
- condition is present and the VP brownout condition is in an attacking state.
-
- - cirrus,vpbr-atk-vol : VP brownout prevention step size. Configures the VP
- brownout prevention attacking attenuation step size when operating in either
- digital volume or analog gain modes.
-
- - cirrus,vpbr-max-attn : Maximum attenuation that the VP brownout prevention
- can apply to the audio signal.
-
- - cirrus,vpbr-wait : Configures the delay time between a brownout condition
- no longer being present and the VP brownout prevention entering an attenuation
- release state.
-
- - cirrus,vpbr-rel-rate : Attenuation release step rate. Configures the delay
- between consecutive volume attenuation release steps when a brownout condition
- is not longer present and the VP brownout is in an attenuation release state.
-
- - cirrus,vpbr-mute-en : During the attack state, if the vpbr-max-attn value
- is reached, the error condition still remains, and this bit is set, the audio
- is muted.
-
-Example:
-
-cs35l36: cs35l36@40 {
- compatible = "cirrus,cs35l36";
- reg = <0x40>;
- VA-supply = <&dummy_vreg>;
- VP-supply = <&dummy_vreg>;
- reset-gpios = <&gpio0 54 0>;
- interrupt-parent = <&gpio8>;
- interrupts = <3 IRQ_TYPE_LEVEL_LOW>;
-
- cirrus,boost-ind-nanohenry = <1000>;
- cirrus,boost-ctl-millivolt = <10000>;
- cirrus,boost-peak-milliamp = <4500>;
- cirrus,boost-ctl-select = <0x00>;
- cirrus,weak-fet-delay = <0x04>;
- cirrus,weak-fet-thld = <0x01>;
- cirrus,temp-warn-threshold = <0x01>;
- cirrus,multi-amp-mode;
- cirrus,irq-drive-select = <0x01>;
- cirrus,irq-gpio-select = <0x01>;
-
- cirrus,vpbr-config {
- cirrus,vpbr-en = <0x00>;
- cirrus,vpbr-thld = <0x05>;
- cirrus,vpbr-atk-rate = <0x02>;
- cirrus,vpbr-atk-vol = <0x01>;
- cirrus,vpbr-max-attn = <0x09>;
- cirrus,vpbr-wait = <0x01>;
- cirrus,vpbr-rel-rate = <0x05>;
- cirrus,vpbr-mute-en = <0x00>;
- };
-};

---
base-commit: 8cd9520d35a6c38db6567e97dd93b1f11f185dc6
change-id: 20260618-dt-cirrus-cs35l36-99c466fb13fd

Best regards,
--
David Heidelberg <david@xxxxxxx>