Linux Sound subsystem development
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From: Mohammad Rafi Shaik <mohammad.rafi.shaik@oss.qualcomm.com>
To: Harendra Gautam <harendra.gautam@oss.qualcomm.com>,
	Srinivas Kandagatla <srini@kernel.org>
Cc: Mark Brown <broonie@kernel.org>,
	Liam Girdwood <lgirdwood@gmail.com>,
	Rob Herring <robh@kernel.org>,
	Krzysztof Kozlowski <krzk+dt@kernel.org>,
	Conor Dooley <conor+dt@kernel.org>,
	Jaroslav Kysela <perex@perex.cz>, Takashi Iwai <tiwai@suse.com>,
	linux-sound@vger.kernel.org, linux-arm-msm@vger.kernel.org,
	devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
	Prasad Kumpatla <prasad.kumpatla@oss.qualcomm.com>,
	Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>,
	Sarath Ganapathiraju <sarath.ganapathiraju@oss.qualcomm.com>,
	Kumar Anurag Singh <kumar.singh@oss.qualcomm.com>
Subject: Re: [PATCH v3 1/9] ASoC: dt-bindings: qcom,qaif-cpu: Add binding
Date: Wed, 26 Aug 2026 14:01:52 +0530	[thread overview]
Message-ID: <bf6e42b4-ff21-4b6c-a7d5-024e5b9a7da4@oss.qualcomm.com> (raw)
In-Reply-To: <20260824063627.3595610-2-harendra.gautam@oss.qualcomm.com>



On 8/24/2026 12:06 PM, Harendra Gautam wrote:
> QAIF routes audio between system memory, external PCM/TDM/MI2S serial
> interfaces and the internal Bolero/WCD codec. Platform Devicetree files
> need a binding to describe the controller resources, DAI cells and per-
> interface AIF configuration, and named constants to avoid raw numeric IDs
> in sound-dai references and child-node reg values.
> 
> Describe the MMIO region, interrupt, clocks, DMA IOMMU mapping and
> aif-interface child nodes required by the controller.
> 
> Signed-off-by: Harendra Gautam <harendra.gautam@oss.qualcomm.com>
> ---
>   .../bindings/sound/qcom,qaif-cpu.yaml         | 307 ++++++++++++++++++
>   include/dt-bindings/sound/qcom,qaif.h         |  97 ++++++
>   2 files changed, 404 insertions(+)
>   create mode 100644 Documentation/devicetree/bindings/sound/qcom,qaif-cpu.yaml
>   create mode 100644 include/dt-bindings/sound/qcom,qaif.h
> 
> diff --git a/Documentation/devicetree/bindings/sound/qcom,qaif-cpu.yaml b/Documentation/devicetree/bindings/sound/qcom,qaif-cpu.yaml
> new file mode 100644
> index 000000000000..134356114733
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/sound/qcom,qaif-cpu.yaml
> @@ -0,0 +1,307 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/sound/qcom,qaif-cpu.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Qualcomm Audio Interface (QAIF) CPU DAI Controller
> +
> +maintainers:
> +  - Harendra Gautam <harendra.gautam@oss.qualcomm.com>
> +
> +description: |
> +  The Qualcomm Audio Interface (QAIF) is a fully configurable DMA-based
> +  audio subsystem controller. It serialises and deserialises PCM audio
> +  between system memory and external serial audio peripherals (PCM, TDM,
> +  I2S, MI2S) through the AIF path, and transfers parallel audio between
> +  memory and an internal WCD codec through the CIF path.
> +
> +  AIF (Audio Interface): up to 13 multi-lane Unified Audio Interfaces,
> +  each supporting up to 8 independent data lanes. Each lane is individually
> +  configurable as TX (output/speaker) or RX (input/mic). All lanes of an
> +  interface share a single bit clock and frame sync. Supported modes are
> +  PCM (short/long sync), TDM, and MI2S (stereo/mono). Per-interface
> +  configuration includes sync source (master/slave), sync mode, sync delay,
> +  sync inversion, slot width (8/16/24/32-bit), sample width, active slot
> +  masks (up to 32 slots), bits-per-lane frame size, lane enable/direction
> +  masks, loopback, output-enable control, and full-cycle path support for
> +  long chip-to-chip connections.
> +
> +  CIF (Codec Interface): up to 10 RDDMA (playback) and 10 WRDMA (capture)
> +  channels connecting to an internal codec over a parallel bus. Each channel
> +  supports active-channel enable mask (up to 16 channels), frame-sync
> +  selection, frame-sync delay, frame-sync output gating, dynamic clock
> +  gating, and 16-bit packing/unpacking.
> +
> +  Note on RX/TX naming convention: in QAIF, TX refers to the output
> +  (speaker/playback) direction and RX refers to the input (mic/capture)
> +  direction. This applies to both AIF lane directions and CIF slot/mask
> +  properties.
> +
> +  DMA engine: RDDMA fetches audio from DDR/TCM/LPM into a shared SRAM
> +  latency buffer (SHRAM) and drains it to the interface. WRDMA collects
> +  data from the interface into SHRAM and writes it to memory. Each DMA
> +  owns a private SHRAM region defined by start address and length registers.
> +  Burst sizes of 1/2/4/8/16 beats (64-bit) are supported with up to 4
> +  outstanding transactions per DMA. Two QSB master ports (QXM0 for TCM,
> +  QXM1 for DDR/LPM) provide the memory interface.
> +
> +  Resources are partitioned among up to 5 Execution Engines (EEs) via
> +  EE map registers. Each EE owns a set of DMAs, audio interfaces, and
> +  interface groups, and receives its own independent interrupt output.
> +  The interrupt hierarchy has a two-level structure: a summary register
> +  identifies the event class (DMA period, underflow/overflow, error
> +  response, audio interface underflow/overflow, group done, rate detector,
> +  VFR), and per-resource status registers identify the specific channel.
> +
> +  Interface grouping (bonding) allows up to 6 groups of audio and codec
> +  interfaces to start synchronously and align their DMA period interrupts
> +  within half a frame duration using the RDDMA padding feature.
> +
> +  Two rate detector blocks measure the frequency of incoming frame sync or
> +  word select signals and generate interrupts on rate change, undetected
> +  rate, or sync timeout.
> +
> +  Block diagram::
> +
> +    System Memory (DDR / LPM / TCM)
> +    +---------------------------------+
> +    |  Circular Buffers (ping-pong)   |
> +    +----------+----------+-----------+
> +               |          ^
> +         64-bit AXI  64-bit AXI
> +               |          |
> +    +----------v----------+-----------+
> +    |        QSB Master Ports         |
> +    |  +----------+  +----------+     |
> +    |  |   QXM0   |  |   QXM1   |     |
> +    |  +----+-----+  +-----+----+     |
> +    +-------|--------------|----------+
> +            |              |
> +    +-------v--------------v----------+
> +    |         Shared RAM (SHRAM)       |
> +    |  +------------+  +------------+ |
> +    |  | QXM0 Read  |  | QXM0 Write | |
> +    |  | SHRAM      |  | SHRAM      | |
> +    |  +------------+  +------------+ |
> +    |  +------------+  +------------+ |
> +    |  | QXM1 Read  |  | QXM1 Write | |
> +    |  | SHRAM      |  | SHRAM      | |
> +    |  +------------+  +------------+ |
> +    +---+--------+--------+-------+---+
> +        |        |        |       |
> +    +---v--+  +--v---+ +--v---+ +-v----+
> +    |RDDMA |  |RDDMA | |WRDMA | |WRDMA |
> +    | AIF  |  | CIF  | | AIF  | | CIF  |
> +    |[0..n]|  |[0..n]| |[0..n]| |[0..n]|
> +    +--+---+  +--+---+ +--+---+ +-+----+
> +       |         |       ^          ^
> +       | TX      | TX    | RX       | RX
> +       v         v       |          |
> +    +--+--------------------+  +----+----------+
> +    |  Unified Audio Intf   |  | Codec DMA     |
> +    |  (AIF 0..12)          |  | Interface     |
> +    |                       |  | (CIF)         |
> +    |  AUD_INTFa block:     |  |               |
> +    |  - Serializer (TX)    |  | RDDMA: DDR -> |
> +    |  - De-serializer (RX) |  |   internal    |
> +    |  - Sync gen/detect    |  |   codec       |
> +    |  - Up to 8 data lanes |  | WRDMA: codec  |
> +    |  - PCM / TDM / MI2S   |  |   -> DDR      |
> +    |  - Near Pad Logic     |  | Up to 16 ch   |
> +    +--+--------------------+  +----+----------+
> +       |  Lane 0..7 (TX/RX)       |  Parallel bus
> +       |  Bit clk + Frame sync    |  + Frame sync
> +       v                          v
> +    +--+--------+          +------+------+
> +    | External  |          | Internal    |
> +    | Serial    |          | Digital     |
> +    | Peripherals|         | Codec       |
> +    | (PCM/TDM/ |          | (Bolero/    |
> +    |  MI2S)    |          |  WCD)       |
> +    +-----------+          +-------------+
> +
> +allOf:
> +  - $ref: dai-common.yaml#
> +
> +properties:
> +  compatible:
> +    const: qcom,shikra-qaif-cpu
> +
> +  reg:
> +    maxItems: 1
> +    description: QAIF core registers
> +
> +  interrupts:
> +    maxItems: 1
> +    description:
> +      QAIF summary interrupt for this Execution Engine. Signals DMA period
> +      completion, buffer underflow/overflow, error response, audio interface
> +      underflow/overflow, interface-group done, rate detector and VFR events.
> +
> +  iommus:
> +    maxItems: 1
> +    description: Phandle to apps_smmu node with sid mask
> +
> +  dma-coherent: true
> +
> +  clocks:
> +    minItems: 5
> +    maxItems: 9
> +
> +  clock-names:
> +    description:
> +      The first five clocks are always required. Any further entries are the
> +      per-AIF bit clocks (aif_if<N>_ibit), supplied in order starting from
> +      AIF interface 0 for as many serial AIF interfaces as the board uses.
> +    minItems: 5
> +    items:
> +      - const: lpass_config
> +      - const: lpass_core_axim
> +      - const: aud_dma
> +      - const: aud_dma_mem
> +      - const: bus
> +      - const: aif_if0_ibit
> +      - const: aif_if1_ibit
> +      - const: aif_if2_ibit
> +      - const: aif_if3_ibit
> +
> +  '#sound-dai-cells':
> +    const: 1
> +
> +  '#address-cells':
> +    const: 1
> +
> +  '#size-cells':
> +    const: 0
> +
> +patternProperties:
> +  '^aif@[0-9a-f]+$':
> +    type: object
> +    description:
> +      QAIF AIF interface child node for PCM, TDM or MI2S configuration.
> +
> +    properties:
> +      reg:
> +        maxItems: 1
> +        description:
> +          DAI ID of the AIF interface (QAIF_MI2S_AIF* or QAIF_TDM_AIF*).
> +
> +      dai-format:
> +        description: Serial audio interface format (MI2S, TDM or PCM).
> +        enum: [i2s, dsp_a, dsp_b]
> +
> +      dai-tdm-slot-width:
> +        $ref: /schemas/types.yaml#/definitions/uint32
> +        enum: [8, 16, 24, 32]
> +        description:
> +          Slot width in bits.
> +
> +      dai-tdm-slot-num:
> +        $ref: /schemas/types.yaml#/definitions/uint32
> +        description:
> +          Number of slots per lane.
> +        minimum: 1
> +        maximum: 32
> +
> +      dai-tdm-slot-rx-mask:
> +        $ref: /schemas/types.yaml#/definitions/uint32-array
> +        description:
> +          Active RX slots, one entry per slot. A nonzero value marks the
> +          slot as active.
> +        minItems: 1
> +        maxItems: 32
> +
> +      dai-tdm-slot-tx-mask:
> +        $ref: /schemas/types.yaml#/definitions/uint32-array
> +        description:
> +          Active TX slots, one entry per slot. A nonzero value marks the
> +          slot as active.
> +        minItems: 1
> +        maxItems: 32
> +
> +      qcom,qaif-aif-lane-map:
> +        $ref: /schemas/types.yaml#/definitions/uint32-array
> +        description:
> +          Per-lane direction map, one entry per lane starting from lane 0.
> +          Use 0 for TX (output/speaker) and 1 for RX (input/mic).
> +        minItems: 1
> +        maxItems: 8
> +        items:
> +          enum: [0, 1]
> +
> +    required:
> +      - reg
> +      - dai-format
> +      - qcom,qaif-aif-lane-map
> +
> +    if:
> +      properties:
> +        dai-format:
> +          enum: [dsp_a, dsp_b]
> +    then:
> +      required:
> +        - dai-tdm-slot-width
> +        - dai-tdm-slot-num
> +        - dai-tdm-slot-rx-mask
> +        - dai-tdm-slot-tx-mask
> +
> +    additionalProperties: false
> +
> +required:
> +  - compatible
> +  - reg
> +  - interrupts
> +  - iommus
> +  - clocks
> +  - clock-names
> +  - '#sound-dai-cells'
> +  - '#address-cells'
> +  - '#size-cells'
> +
> +unevaluatedProperties: false
> +
> +examples:
> +  - |
> +    soc {
> +        #address-cells = <2>;
> +        #size-cells = <2>;
> +
> +        qaif_cpu: audio-controller@a000000 {
> +            compatible = "qcom,shikra-qaif-cpu";
> +            reg = <0x0 0x0a000000 0x0 0x20000>;
> +            interrupts = <0 331 4>;
> +            iommus = <&apps_smmu 0x1c0 0x0>;
> +            clocks = <&gcc 213>,
> +                     <&gcc 214>,
> +                     <&audiocorecc 15>,
> +                     <&audiocorecc 17>,
> +                     <&audiocorecc 18>,
> +                     <&audiocorecc 5>,
> +                     <&audiocorecc 8>,
> +                     <&audiocorecc 11>,
> +                     <&audiocorecc 14>;
> +            clock-names = "lpass_config",
> +                          "lpass_core_axim",
> +                          "aud_dma",
> +                          "aud_dma_mem",
> +                          "bus",
> +                          "aif_if0_ibit",
> +                          "aif_if1_ibit",
> +                          "aif_if2_ibit",
> +                          "aif_if3_ibit";
> +            #sound-dai-cells = <1>;
> +            #address-cells = <1>;
> +            #size-cells = <0>;
> +
> +            aif@d7 {
> +                reg = <215>;
> +                dai-format = "dsp_a";
> +                dai-tdm-slot-width = <32>;
> +                dai-tdm-slot-num = <2>;
> +                dai-tdm-slot-rx-mask = <1 1>;
> +                dai-tdm-slot-tx-mask = <1 1>;
> +                qcom,qaif-aif-lane-map = <1 0>;
> +            };
> +        };
> +    };
> diff --git a/include/dt-bindings/sound/qcom,qaif.h b/include/dt-bindings/sound/qcom,qaif.h
> new file mode 100644
> index 000000000000..24706efd07d1
> --- /dev/null
> +++ b/include/dt-bindings/sound/qcom,qaif.h
> @@ -0,0 +1,97 @@
> +/* SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) */
> +/*
> + * Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries.
> + *
> + * DAI IDs for the Qualcomm Audio Interface (QAIF) controller.
> + * QAIF_MI2S_AIF* and QAIF_TDM_AIF* values are used in sound-dai
> + * references and as the reg value of aif@N child nodes.
> + * QAIF_CDC_DMA_* values are for sound-dai references only and must
> + * not be used as aif@N child node reg values.
> + */
> +#ifndef __DT_QCOM_QAIF_H
> +#define __DT_QCOM_QAIF_H
> +
> +/*
> + * MI2S DAI IDs -- one per physical AIF port in MI2S mode.
> + * Each port supports up to 2 channels (stereo I2S) over a single
> + * data lane sharing a bit clock and frame sync.
> + */
> +#define QAIF_MI2S_AIF0		200
> +#define QAIF_MI2S_AIF1		201
> +#define QAIF_MI2S_AIF2		202
> +#define QAIF_MI2S_AIF3		203
> +#define QAIF_MI2S_AIF4		204
> +#define QAIF_MI2S_AIF5		205
> +#define QAIF_MI2S_AIF6		206
> +#define QAIF_MI2S_AIF7		207
> +#define QAIF_MI2S_AIF8		208
> +#define QAIF_MI2S_AIF9		209
> +#define QAIF_MI2S_AIF10		210
> +#define QAIF_MI2S_AIF11		211
> +#define QAIF_MI2S_AIF12		212
> +
> +/*
> + * TDM DAI IDs -- one per physical AIF port in TDM mode.
> + * Each port supports up to 8 channels over up to 8 independent data
> + * lanes sharing a single bit clock and frame sync.
> + */
> +#define QAIF_TDM_AIF0		213
> +#define QAIF_TDM_AIF1		214
> +#define QAIF_TDM_AIF2		215
> +#define QAIF_TDM_AIF3		216
> +#define QAIF_TDM_AIF4		217
> +#define QAIF_TDM_AIF5		218
> +#define QAIF_TDM_AIF6		219
> +#define QAIF_TDM_AIF7		220
> +#define QAIF_TDM_AIF8		221
> +#define QAIF_TDM_AIF9		222
> +#define QAIF_TDM_AIF10		223
> +#define QAIF_TDM_AIF11		224
> +#define QAIF_TDM_AIF12		225
> +
> +/*
> + * CIF (Codec Interface) RX DAI IDs -- playback to internal codec.
> + * RDDMA channels fetch audio from memory and drain it to the codec.
> + */
> +#define QAIF_CDC_DMA_RX0	226
> +#define QAIF_CDC_DMA_RX1	227
> +#define QAIF_CDC_DMA_RX2	228
> +#define QAIF_CDC_DMA_RX3	229
> +#define QAIF_CDC_DMA_RX4	230
> +#define QAIF_CDC_DMA_RX5	231
> +#define QAIF_CDC_DMA_RX6	232
> +#define QAIF_CDC_DMA_RX7	233
> +#define QAIF_CDC_DMA_RX8	234
> +#define QAIF_CDC_DMA_RX9	235
> +
> +/*
> + * CIF (Codec Interface) TX DAI IDs -- capture from internal codec.
> + * WRDMA channels collect audio from the codec and write it to memory.
> + */
> +#define QAIF_CDC_DMA_TX0	236
> +#define QAIF_CDC_DMA_TX1	237
> +#define QAIF_CDC_DMA_TX2	238
> +#define QAIF_CDC_DMA_TX3	239
> +#define QAIF_CDC_DMA_TX4	240
> +#define QAIF_CDC_DMA_TX5	241
> +#define QAIF_CDC_DMA_TX6	242
> +#define QAIF_CDC_DMA_TX7	243
> +#define QAIF_CDC_DMA_TX8	244
> +#define QAIF_CDC_DMA_TX9	245
> +
> +/*
> + * CIF (Codec Interface) VA TX DAI IDs -- capture from voice activity codec.
> + * WRDMA channels collect audio from the VA codec and write it to memory.
> + */
> +#define QAIF_CDC_DMA_VA_TX0	246
> +#define QAIF_CDC_DMA_VA_TX1	247
> +#define QAIF_CDC_DMA_VA_TX2	248
> +#define QAIF_CDC_DMA_VA_TX3	249
> +#define QAIF_CDC_DMA_VA_TX4	250
> +#define QAIF_CDC_DMA_VA_TX5	251
> +#define QAIF_CDC_DMA_VA_TX6	252
> +#define QAIF_CDC_DMA_VA_TX7	253
> +#define QAIF_CDC_DMA_VA_TX8	254
> +#define QAIF_CDC_DMA_VA_TX9	255
> +

These DAI IDs exceed the LPASS_MAX_PORT limit, which will cause sound 
card registration to fail.

Check sound/soc/qcom/common.c, as the current indices (246-255) are 
beyond the supported LPASS port range.

Best Regards,
Rafi.

> +#endif /* __DT_QCOM_QAIF_H */


  parent reply	other threads:[~2026-08-26  8:32 UTC|newest]

Thread overview: 32+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-08-24  6:36 [PATCH v3 0/9] ASoC: qcom: Add QAIF driver for Shikra audio platform Harendra Gautam
2026-08-24  6:36 ` [PATCH v3 1/9] ASoC: dt-bindings: qcom,qaif-cpu: Add binding Harendra Gautam
2026-08-24  8:39   ` Manuel Ebner
2026-08-24  9:14     ` Harendra Gautam
2026-08-25  5:59     ` Krzysztof Kozlowski
2026-08-26  8:31   ` Mohammad Rafi Shaik [this message]
2026-08-26  9:39     ` Harendra Gautam
2026-08-26  9:43       ` Srinivas Kandagatla
2026-08-26  9:55         ` Harendra Gautam
2026-08-26 10:01           ` Srinivas Kandagatla
2026-08-26 10:06             ` Harendra Gautam
2026-08-26 10:25               ` Harendra Gautam
2026-08-26 23:32     ` Mark Brown
2026-08-27  4:00       ` Harendra Gautam
2026-08-24  6:36 ` [PATCH v3 2/9] ASoC: qcom: Add QAIF shared data structures and variant interface Harendra Gautam
2026-08-24  6:36 ` [PATCH v3 3/9] ASoC: qcom: Add QAIF hardware register map Harendra Gautam
2026-08-24  6:36 ` [PATCH v3 4/9] ASoC: qcom: Add QAIF CPU DAI ops, regmap, DT parsing and platform init Harendra Gautam
2026-08-24  6:36 ` [PATCH v3 5/9] ASoC: soc-core: Add snd_soc_of_xlate_dai_name() generic helper Harendra Gautam
2026-08-25  4:20   ` Kuninori Morimoto
2026-08-24  6:36 ` [PATCH v3 6/9] ASoC: qcom: Add QAIF PCM operations Harendra Gautam
2026-08-24  9:25   ` Markus Elfring
2026-08-24 10:10     ` Harendra Gautam
2026-08-25  6:07       ` Krzysztof Kozlowski
2026-08-24  6:36 ` [PATCH v3 7/9] ASoC: qcom: Add QAIF IRQ handling, suspend/resume and platform register Harendra Gautam
2026-08-24  6:36 ` [PATCH v3 8/9] ASoC: qcom: Add Shikra QAIF support Harendra Gautam
2026-08-26  8:35   ` Mohammad Rafi Shaik
2026-08-26  8:58     ` Harendra Gautam
2026-08-26 10:13       ` Srinivas Kandagatla
2026-08-26 10:37         ` Harendra Gautam
2026-08-24  6:36 ` [PATCH v3 9/9] MAINTAINERS: Add Qualcomm QAIF driver entry Harendra Gautam
2026-08-24  8:22   ` Abel Vesa
2026-08-24  8:31     ` Harendra Gautam

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