[PATCH v5 0/2] Introduces MDSYNC support for CS35L45

From: Ricardo Rivera-Matos

Date: Fri Aug 28 2026 - 11:48:19 EST


The CS35L45 has SYNC pin that can be used as a multi
device synchronization (MDSYNC) bus. This pin can send
various message types between Cirrus devices.

This patch series adds support for long and short DSP
messages between CS35L45 devices.

Each device on the SYNC bus must have a unique transmitter
identifier per message type as the bus arbitrates message
priority via this identifier. These identifiers are set by
the introduced devicetree properties. The priority
assignment is intended to be a static system integration
decision.

The relevant receiver controls are introduced as mixer
controls so they are exposed at runtime to be configured
for the appropriate use cases.

Signed-off-by: Ricardo Rivera-Matos <rriveram@xxxxxxxxxxxxxxxxxxxxx>
---
Changes in v5:
- Flattened sync node in favor sync properties directly under cs35l45
node
- Using device_property_read_u32() now that sync node has been flattened
- Apply sync config immediately when GPIO1 is configured as SYNC pin
- Normalize SYNC Enable mixer value when comparing and storing
- Link to v4: https://lore.kernel.org/r/20260821-sound-for-next-cs35l45-sync-v4-v4-0-20d3a07c3b8d@xxxxxxxxxxxxxxxxxxxxx

Changes in v4:
- return 0 when controls are unchanged
- adds locking to cs35l45_sync_en_put
- Enable -> Switch

Changes in v3:
- snd_soc_kcontrol_component -> snd_kcontrol_chip
- only register sync controls if GPIO mux selects SYNC
- return 1 on cs35l45_sync_en_put success
- drop | in dt property description

Changes in v2:
- Fixed property parsing namespace issue

---
Ricardo Rivera-Matos (2):
ASoC: dt-bindings: cs35l45: Adds SYNC properties
ASoC: cs35l45: Adds support for SYNC bus

.../devicetree/bindings/sound/cirrus,cs35l45.yaml | 20 +++++
sound/soc/codecs/cs35l45-tables.c | 4 +
sound/soc/codecs/cs35l45.c | 89 +++++++++++++++++++++-
sound/soc/codecs/cs35l45.h | 23 ++++++
4 files changed, 132 insertions(+), 4 deletions(-)
---
base-commit: ab07442c27d0f9fa3aee4185fcb3dbf521fac746
change-id: 20260821-sound-for-next-cs35l45-sync-v4-c2664a7bd536

Best regards,
--
Ricardo Rivera-Matos <rriveram@xxxxxxxxxxxxxxxxxxxxx>