The SOF compressed offload path accepts codec parameters in
sof_compr_set_params() and forwards them to firmware as
extended data in the SOF IPC stream params message.

However, sof_compr_get_params() still returns success without
filling the snd_codec structure. Since the compress core allocates
that structure zeroed and copies it back to userspace on success,
SNDRV_COMPRESS_GET_PARAMS returns an all-zero codec description
even after the stream has been configured successfully.

The stale TODO in this callback conflates get_params() with capability
discovery. Supported codec enumeration belongs in get_caps() and
get_codec_caps(). get_params() should report the current codec settings.

Cache the codec accepted by sof_compr_set_params() in the per-stream SOF
compress state and return it from sof_compr_get_params().

Fixes: 6324cf901e14 ("ASoC: SOF: compr: Add compress ops implementation")
Signed-off-by: Cássio Gabriel <cassiogabrielcontato@gmail.com>
---
 sound/soc/sof/compress.c | 8 +++++---
 sound/soc/sof/sof-priv.h | 2 ++
 2 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/sound/soc/sof/compress.c b/sound/soc/sof/compress.c
index 3dbc05bf3b79..f4c3e10e6344 100644
--- a/sound/soc/sof/compress.c
+++ b/sound/soc/sof/compress.c
@@ -255,6 +255,7 @@ static int sof_compr_set_params(struct snd_soc_component *component,
 	sstream->sampling_rate = params->codec.sample_rate;
 	sstream->channels = params->codec.ch_out;
 	sstream->sample_container_bytes = pcm->params.sample_container_bytes;
+	sstream->codec_params = params->codec;
 
 	spcm->prepared[cstream->direction] = true;
 
@@ -267,9 +268,10 @@ static int sof_compr_set_params(struct snd_soc_component *component,
 static int sof_compr_get_params(struct snd_soc_component *component,
 				struct snd_compr_stream *cstream, struct snd_codec *params)
 {
-	/* TODO: we don't query the supported codecs for now, if the
-	 * application asks for an unsupported codec the set_params() will fail.
-	 */
+	struct sof_compr_stream *sstream = cstream->runtime->private_data;
+
+	*params = sstream->codec_params;
+
 	return 0;
 }
 
diff --git a/sound/soc/sof/sof-priv.h b/sound/soc/sof/sof-priv.h
index 693d063830fa..38753b088fc1 100644
--- a/sound/soc/sof/sof-priv.h
+++ b/sound/soc/sof/sof-priv.h
@@ -17,6 +17,7 @@
 #include <sound/sof/info.h>
 #include <sound/sof/pm.h>
 #include <sound/sof/trace.h>
+#include <sound/compress_params.h>
 #include <uapi/sound/sof/fw.h>
 #include <sound/sof/ext_manifest.h>
 
@@ -111,6 +112,7 @@ struct sof_compr_stream {
 	u32 sampling_rate;
 	u16 channels;
 	u16 sample_container_bytes;
+	struct snd_codec codec_params;
 	size_t posn_offset;
 };
 

---
base-commit: 5c3743212c70461c076cb11c83c899695a1528f8
change-id: 20260325-sof-compr-get-params-660c3350e173

Best regards,
--  
Cássio Gabriel <cassiogabrielcontato@gmail.com>