[PATCH] ALSA: aoa: Handle empty codec list in i2sbus_pcm_prepare()

Thorsten Blum
2026-03-09T11:51:54Z

Replace two list_for_each_entry() loops with list_first_entry_or_null()
in i2sbus_pcm_prepare().

Handle an empty codec list explicitly by returning -ENODEV, which avoids
using uninitialized 'bi.sysclock_factor' in the 32-bit code path.

Fixes: f3d9478b2ce4 ("[ALSA] snd-aoa: add snd-aoa")
Cc: stable@vger.kernel.org
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
---
sound/aoa/soundbus/i2sbus/pcm.c | 22 +++++++++++-----------
1 file changed, 11 insertions(+), 11 deletions(-)

diff --git a/sound/aoa/soundbus/i2sbus/pcm.c b/sound/aoa/soundbus/i2sbus/pcm.c
index aff99003d833..65653601662d 100644
--- a/sound/aoa/soundbus/i2sbus/pcm.c
+++ b/sound/aoa/soundbus/i2sbus/pcm.c
@@ -314,7 +314,7 @@ static int i2sbus_pcm_prepare(struct i2sbus_dev *i2sdev, int in)
int i, periodsize, nperiods;
dma_addr_t offset;
struct bus_info bi;
- struct codec_info_item *cii;
+ struct codec_info_item *cii = NULL;
int sfr = 0; /* serial format register */
int dws = 0; /* data word sizes reg */
int input_16bit;
@@ -390,13 +390,11 @@ static int i2sbus_pcm_prepare(struct i2sbus_dev *i2sdev, int in)
case SNDRV_PCM_FORMAT_U16_BE:
/* FIXME: if we add different bus factors we need to
* do more here!! */
- bi.bus_factor = 0;
- list_for_each_entry(cii, &i2sdev->sound.codec_list, list) {
- bi.bus_factor = cii->codec->bus_factor;
- break;
- }
- if (!bi.bus_factor)
+ cii = list_first_entry_or_null(&i2sdev->sound.codec_list,
+ struct codec_info_item, list);
+ if (!cii)
return -ENODEV;
+ bi.bus_factor = cii->codec->bus_factor;
input_16bit = 1;
break;
case SNDRV_PCM_FORMAT_S32_BE:
@@ -410,10 +408,12 @@ static int i2sbus_pcm_prepare(struct i2sbus_dev *i2sdev, int in)
return -EINVAL;
}
/* we assume all sysclocks are the same! */
- list_for_each_entry(cii, &i2sdev->sound.codec_list, list) {
- bi.sysclock_factor = cii->codec->sysclock_factor;
- break;
- }
+ if (!cii)
+ cii = list_first_entry_or_null(&i2sdev->sound.codec_list,
+ struct codec_info_item, list);
+ if (!cii)
+ return -ENODEV;
+ bi.sysclock_factor = cii->codec->sysclock_factor;

if (clock_and_divisors(bi.sysclock_factor,
bi.bus_factor,