ASoC: sdca: test adev before calling acpi_dev_for_each_child

sdca_lookup_functions may be called by a Peripheral that is not listed
in the ACPI table. Testing adev is required to avoid kernel NULL pointer
dereference.

Fixes: 3a513da1ae33 ("ASoC: SDCA: add initial module")
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com>
Reviewed-by: Liam Girdwood <liam.r.girdwood@intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Link: https://patch.msgid.link/20241113064133.162501-1-yung-chuan.liao@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/sound/soc/sdca/sdca_functions.c b/sound/soc/sdca/sdca_functions.c
index a6ad57430dd4be9ce2701e9f340b8a11e7320642..e6e5629c7054e81056cc2f9fb00d04355ac19254 100644 (file)
--- a/sound/soc/sdca/sdca_functions.c
+++ b/sound/soc/sdca/sdca_functions.c
@@ -165,6 +165,10 @@ void sdca_lookup_functions(struct sdw_slave *slave)
        struct device *dev = &slave->dev;
        struct acpi_device *adev = to_acpi_device_node(dev->fwnode);
 
+       if (!adev) {
+               dev_info(dev, "No matching ACPI device found, ignoring peripheral\n");
+               return;
+       }
        acpi_dev_for_each_child(adev, find_sdca_function, &slave->sdca_data);
 }
 EXPORT_SYMBOL_NS(sdca_lookup_functions, SND_SOC_SDCA);