Re: [PATCH v6 1/2] dt-bindings: input: Add Qualcomm SPMI PMIC haptics

[Rob Herring]

On Thu, Aug 06, 2026 at 11:21:40PM -0700, Fenglin Wu wrote:
> Add binding document for the haptics module inside Qualcomm PMIC
> PMIH0108.
> 
> Assisted-by: Claude:claude-4-8-opus
> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxxxxxxxx>
> Signed-off-by: Fenglin Wu <fenglin.wu@xxxxxxxxxxxxxxxx>
> ---
>  .../bindings/input/qcom,spmi-haptics.yaml          | 136 +++++++++++++++++++++
>  1 file changed, 136 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/input/qcom,spmi-haptics.yaml b/Documentation/devicetree/bindings/input/qcom,spmi-haptics.yaml
> new file mode 100644
> index 000000000000..b1a69e9886ee
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/input/qcom,spmi-haptics.yaml
> @@ -0,0 +1,136 @@
> +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/input/qcom,spmi-haptics.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Haptics device inside Qualcomm Technologies, Inc. PMIC
> +
> +maintainers:
> +  - Fenglin Wu <fenglin.wu@xxxxxxxxxxxxxxxx>
> +
> +description: |
> +  Certain Qualcomm PMICs integrate a haptics module, such as the HAP530_HV haptics
> +  module in the PMIH0108 PMIC, which drives an LRA (Linear Resonant Actuator) with
> +  an output voltage up to 10 V. Several play modes are supported in HAP530_HV:
> +
> +    DIRECT_PLAY: The hardware outputs sinusoidal waveforms whose period is
> +      defined by qcom,lra-period-us and whose peak voltage is defined by
> +      qcom,vmax-microvolt. The driving amplitude can be scaled in the range
> +      [0, 255] via a single register byte.  Hardware-based LRA auto-resonance
> +      tracking is enabled by default in this mode, allowing the haptics engine
> +      to follow the actual resonant frequency of the LRA and update the driving
> +      period accordingly to achieve stronger vibration magnitude.
> +
> +    FIFO: The hardware can play an arbitrary waveform composed of a sequence
> +      of 8-bit samples at a configurable play rate.  Samples are pre-filled
> +      into the internal FIFO memory of the haptics module and continuously
> +      replenished via the FIFO-empty IRQ until all samples have been played.
> +      An 8K-byte FIFO memory bank is available in the HAP530_HV haptics module,
> +      shared between the FIFO and PAT_MEM play modes. The memory partition
> +      between the two modes is configurable via registers, and FIFO mode always
> +      uses the 1st partition starting from offset 0.
> +
> +    PAT_MEM: This mode is very similar to FIFO streaming mode but without the
> +      data refilling capability. It is designed mainly for short, latency-critical
> +      vibrations. The memory space for PAT_MEM mode must be reserved for dedicated
> +      usage, and the waveform data should be preloaded and remain unchanged
> +      thereafter. The haptics module can play the waveform data from the memory
> +      region specified by the PAT_MEM play start address and length registers.
> +
> +    In either FIFO mode or PAT_MEM mode, the following play rates are supported:
> +      -- 0(T_LRA): each FIFO byte drives one full sinusoidal cycle with the
> +        period defined in qcom,lra-period-us.
> +      -- 1/2/3(T_LRA_DIV_2/4/8): each FIFO byte drives a half/quarter/eighth
> +        sinusoidal cycle with the period defined in qcom,lra-period-us.
> +      -- 4/5/6(T_LRA_X_2/4/8): each FIFO byte drives 2/4/8 sinusoidal cycles
> +        with the period defined in qcom,lra-period-us.
> +      -- 8/9/10/11/12/13(8KHz/16KHz/24KHz/32KHz/44.1KHz/48KHz): the FIFO
> +        data is treated as PCM samples and drives the output with an
> +        arbitrarily shaped waveform.  This mode is typically used to define
> +        custom driving waveforms for specific vibration effects such as fast
> +        attack, crisp brake, etc.
> +
> +    The drive voltage in FIFO or PAT_MEM mode can exceed the value defined in
> +    qcom,vmax-microvolt to achieve a special vibration effect, but the waveform
> +    must be short enough to prevent the LRA from being damaged by operating at
> +    an overvoltage.
> +
> +    Also, hardware-based LRA auto-resonance tracking is normally disabled in
> +    FIFO or PAT_MEM mode, as these modes are intended to drive arbitrary
> +    waveforms that may not follow the resonant frequency; autonomous hardware
> +    resonance correction would interfere with the intended output.
> +
> +properties:
> +  compatible:
> +    items:
> +      - const: qcom,pmih0108-haptics
> +      - const: qcom,spmi-haptics
> +
> +  reg:
> +    items:
> +      - description: HAP_CFG module base address
> +      - description: HAP_PTN module base address
> +
> +  reg-names:
> +    items:
> +      - const: cfg
> +      - const: ptn
> +
> +  interrupts:
> +    maxItems: 1
> +
> +  interrupt-names:
> +    items:
> +      - const: fifo-empty
> +
> +  qcom,vmax-microvolt:
> +    description:
> +      Maximum allowed output driving voltage in microvolts, must be a multiple
> +      of 50,000 uV. This is the peak driving voltage in DIRECT_PLAY mode,
> +      which outputs sinusoidal waveforms. The value should be equal to the
> +      square root of 2 times the Vrms voltage of the LRA.
> +    minimum: 50000
> +    maximum: 10000000
> +    multipleOf: 50000
> +
> +  qcom,lra-period-us:
> +    description:
> +      LRA actuator initial resonance period in microseconds
> +      (1,000,000 / resonant_freq_hz).  Used to configure T_LRA-based play
> +      rates and the auto-resonance zero-crossing window. It could be also used
> +      as the initial period if the LRA wants to be driven off resonance.
> +    minimum: 5
> +    maximum: 20475
> +    multipleOf: 5
> +
> +required:
> +  - compatible
> +  - reg
> +  - reg-names
> +  - interrupts
> +  - interrupt-names
> +  - qcom,vmax-microvolt
> +  - qcom,lra-period-us
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/interrupt-controller/irq.h>
> +
> +    pmic {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        haptics@f000 {

No incomplete examples please. Put this in the example for the PMIC.

And please comment on sashiko report. Looks valid to me.

Rob