ASoC: fsl-asoc-card: Restructure to support deferrable card binding

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Chancel Liu <chancel.liu@nxp.com> says:

The ASoC core has evolved over several kernel releases to support
deferrable card binding: when a component is not yet available,
devm_snd_soc_register_card() no longer propagates -EPROBE_DEFER back to
the machine driver. Instead the card is placed on an internal deferred
list and rebound automatically once the missing component registers.
As a result, registering a sound card no longer guarantees that all CPU
and codec components have already probed successfully.

This exposed two regressions in fsl-asoc-card:

1. The machine driver caches codec MCLK rate during probe(). On platforms
   where the MCLK is derived from the CPU DAI clock and its final rate is
   applied via assigned-clocks in the CPU DAI node, probing before the CPU
   DAI driver completes leaves fsl-asoc-card with a stale mclk_freq.

2. If a card defers due to a missing component, it queues the card onto
   the unbind_card_list and returns 0. The driver then proceeds to call
   simple_util_init_jack(). At this point, the snd_card pointer is NULL.

Patch 1 drops mclk management for nau8822 from this machine driver.

Patch 2 is a pure refactoring with no functional change. the large if/else
chain of of_device_is_compatible() calls in probe() is
replaced by a platform data table approach.

Patch 3 moves all component-dependent initialisation and jacks out of
probe() and into late_probe(), which is the correct place under the
deferrable binding model.

Link: https://patch.msgid.link/20260810093834.1511749-1-chancel.liu@oss.nxp.com

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Mark Brown 2026-08-13 15:49:35 +01:00

parent 87331e2aa4 de27e0cadc

commit 802ff936c7

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sound/soc/fsl/fsl-asoc-card.c

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