[PATCH v2 05/11] ASoC: SDCA: add populate_function hw_op for DT function data

From: Srinivas Kandagatla

Date: Mon Sep 07 2026 - 05:01:38 EST


sdca_parse_function() walks a firmware node, but on DT there is no
DisCo node -- sdca_lookup_functions() is a no-op and the SDCA
function descriptors come with a NULL fwnode.

Add a populate_function hw_op that the class function driver falls
back to when @function->desc->node is NULL: it fills the caller-owned
sdca_function_data (entities, clusters, init_table, delays) from the
codec's static tables, matching by function type. Leave
@function->desc alone -- the framework owns the per-instance
descriptor, so devices with more than one function of the same type
keep their per-instance SoundWire address.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxxxxxxxx>
---
include/sound/sdca_class.h | 6 ++++++
sound/soc/sdca/sdca_class_function.c | 9 ++++++++-
2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/include/sound/sdca_class.h b/include/sound/sdca_class.h
index 3342937d09fd..3a1b6d65048f 100644
--- a/include/sound/sdca_class.h
+++ b/include/sound/sdca_class.h
@@ -26,9 +26,15 @@ struct sdca_function_data;
* before the class regmap is created and before the slave is
* ATTACHED; callers needing bus I/O must sdw_slave_wait_for_init()
* first.
+ * @populate_function: fill @function (entities, clusters, init_table, ...)
+ * from static tables in place of sdca_parse_function() on
+ * DT/non-DisCo platforms. Must leave @function->desc alone.
+ * Return 0 on success or a negative errno. May be NULL.
*/
struct sdca_class_hw_ops {
int (*hw_init)(struct sdw_slave *slave);
+ int (*populate_function)(struct sdw_slave *slave,
+ struct sdca_function_data *function);
};

struct sdca_class_drv {
diff --git a/sound/soc/sdca/sdca_class_function.c b/sound/soc/sdca/sdca_class_function.c
index 10a2b031b572..8bca88865a4d 100644
--- a/sound/soc/sdca/sdca_class_function.c
+++ b/sound/soc/sdca/sdca_class_function.c
@@ -329,7 +329,14 @@ static int class_function_probe(struct auxiliary_device *auxdev,
drv->core = core;
drv->function = &sdev->function;

- ret = sdca_parse_function(dev, drv->function);
+ if (drv->function->desc->node) {
+ ret = sdca_parse_function(dev, drv->function);
+ } else if (core->hw_ops && core->hw_ops->populate_function) {
+ ret = core->hw_ops->populate_function(core->sdw, drv->function);
+ } else {
+ dev_err(dev, "no firmware node and no populate_function hook\n");
+ return -ENOENT;
+ }
if (ret)
return ret;

--
2.53.0