On 3/26/2026 3:40 PM, Krzysztof Kozlowski wrote:

On 26/03/2026 10:57, Mohammad Rafi Shaik wrote:

quoted

On 3/17/2026 12:41 PM, Krzysztof Kozlowski wrote:

quoted

On 17/03/2026 06:27, Mohammad Rafi Shaik wrote:

quoted

On 3/10/2026 3:25 PM, Krzysztof Kozlowski wrote:

quoted

On Mon, Mar 09, 2026 at 04:42:57PM +0530, Mohammad Rafi Shaik wrote:

quoted

Extend the qcom,q6apm-lpass-dais device tree binding to explicitly
describe Digital Audio Interface (DAI) child nodes.

Add #address-cells and #size-cells to allow representation of multiple
DAI instances as child nodes, and define a dai@<id> pattern to document
per-DAI properties such as the interface ID and associated clocks.

Qualcomm platforms like talos integrate third-party audio codecs or use
different external audio paths. These designs often require additional
configuration such as explicit MI2S MCLK settings for audio to work.

Co-developed-by: Srinivas Kandagatla <redacted>
Signed-off-by: Srinivas Kandagatla <redacted>
Signed-off-by: Mohammad Rafi Shaik <redacted>
---
    .../bindings/sound/qcom,q6apm-lpass-dais.yaml | 41 ++++++++++++++++++-
    1 file changed, 40 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/sound/qcom,q6apm-lpass-dais.yaml b/Documentation/devicetree/bindings/sound/qcom,q6apm-lpass-dais.yaml
index 2fb95544d..1d770cbcb 100644
--- a/Documentation/devicetree/bindings/sound/qcom,q6apm-lpass-dais.yaml
+++ b/Documentation/devicetree/bindings/sound/qcom,q6apm-lpass-dais.yaml

@@ -21,6 +21,34 @@ properties:
      '#sound-dai-cells':
        const: 1
    
+  '#address-cells':
+    const: 1
+
+  '#size-cells':
+    const: 0
+
+# Digital Audio Interfaces
+patternProperties:
+  '^dai@[0-9]+$':
+    type: object
+    description:
+      Q6DSP Digital Audio Interfaces.
+
+    properties:
+      reg:
+        description:
+          Digital Audio Interface ID
+
+      clocks:
+        minItems: 1
+        maxItems: 3
+
+      clock-names:
+        minItems: 1
+        maxItems: 3

No, this is just way too generic. There is no such syntax in the kernel
and this should stop you right there. You are not allowed to add your
own style.

I don't think DAI is here a separate device needing its own resources
expressed in DT. This is still part of ADSP so you just described in DT
internal routing between two services on ADSP.

Thanks for reviewing.

I’d like to clarify that this is not intended to model the DAI as a
separate physical device or to describe internal ADSP routing.

If you do not want to represent the physical device, then I don't think
it should be represented at all.

quoted

Requirement is to allow the kernel to send clock‑voting requests to the
ADSP. LPASS MCLK routing is not enabled by default on the ADSP, so the
kernel must explicitly request the ADSP to enable the relevant LPASS
MCLKs, which is a real hardware control requirement.

These clocks are LPASS‑owned, and driving them via a third‑party codec
is not appropriate. The intent of adding clock capabilities at the DAI
level is to allow the kernel to associate LPASS clock votes with a
specific DAI instance during stream activity.

While the DAI itself is not a physical device, some DT representation is
required to describe per‑DAI LPASS clock requirements.

DT's purpose is not to describe software constructs, thus DT is not the
answer to your requirement of mapping clocks to specific DAI needs.
Every person adding software properties made "some DT representation is
required" claim.

quoted

I’m open to considering alternative representations, but removing this
entirely would leave no generic way for the kernel to handle correct
LPASS MCLK voting.

I imagine that, since this is software construct, the software knows
which DAI needs which clock. Clocks are strictly defined, thus driver
should handle all this.

No, the MCLK connection is not fixed to a specific DAI.

The LPASS MCLKs
LPASS_CLK_ID_MCLK_1 … LPASS_CLK_ID_MCLK_5

are hard‑wired connection, each physically routed to an external codec
on the board.

Because of this, the clock that must be voted depends purely on the
hardware wiring, not on which DAI (Primary/Secondary/Tertiary/Quaternary
MI2S) is used.

If they are routed to external codecs, then they are already present in
these nodes and duplicating them here is not necessary.

quoted

In other words, DAI ↔ MCLK is not a fixed mapping.

Examples:
On Talos‑EVK, the speaker is connected via Primary MI2S, but the
corresponding MCLK line wired to the codec is LPASS_CLK_ID_MCLK_2.

On Kodiak, the customer connected an SGTL5000 codec via Quaternary MI2S,
yet the required MCLK is still LPASS_CLK_ID_MCLK_2.

Instead, the kernel must vote for the MCLK that is physically connected
to the external codec on that specific board.

No, the external codec driver must vote for that MCLK.

I agree that when the MCLK provider is external, it is appropriate for 
the codec driver to manage that clock. However, in this case the MCLK 
provider is the LPASS/DSP subsystem itself, and the external codec is 
only a consumer.

LPASS MCLKs configurations inside the DSP can be lost or reprogrammed 
during DSP power collapse or subsystem restart (SSR).

Without visibility into LPASS lifecycle(SSR) events, a third‑party codec 
driver cannot reliably perform clock voting or restoration, resulting in 
broken or inconsistent audio behavior.

For these reasons, MCLK voting needs to remain owned by the LPASS/HLOS 
drivers, which have awareness of DSP power state and board wiring,

Thanks & Regards,
Rafi.

Best regards,
Krzysztof