ucm: find-device / pcm - the ctl_list may be empty

Signed-off-by: Jaroslav Kysela <perex@perex.cz>

diff --git a/src/ucm/ucm_subs.c b/src/ucm/ucm_subs.c
index 5cffcf8fb3b7962adbb5ae189bcc45aa6fce078f..c9023460758ceba96cd4e4046752b3fc2e8ab649 100644 (file)
--- a/src/ucm/ucm_subs.c
+++ b/src/ucm/ucm_subs.c
@@ -467,6 +467,10 @@ static int rval_device_lookup_init(snd_use_case_mgr_t *uc_mgr,
 
        if (snd_config_search(config, "ctl", &d) || snd_config_get_string(d, &s)) {
                iter->ctl_list = uc_mgr_get_master_ctl(uc_mgr);
+               if (iter->ctl_list == NULL) {
+                       uc_error("Control device is not defined!");
+                       return -EINVAL;
+               }
        } else {
                err = uc_mgr_open_ctl(uc_mgr, &iter->ctl_list, s, 1);
                if (err < 0) {