ALSA was testing if (format) was set to zero as an error condition, but

 SND_PCM_FORMAT_S8 is zero, so you could never open ALSA for AUDIO_S8 data
 before.

--HG--
extra : convert_revision : svn%3Ac70aab31-4412-0410-b14c-859654838e24/trunk%402056

src/audio/alsa/SDL_alsa_audio.c

@@ -523,6 +523,7 @@ ALSA_OpenAudio(_THIS, SDL_AudioSpec * spec)
     status = -1;
     for (test_format = SDL_FirstAudioFormat(spec->format);
          test_format && (status < 0);) {
+        status = 0;  /* if we can't support a format, it'll become -1. */
         switch (test_format) {
         case AUDIO_U8:
             format = SND_PCM_FORMAT_U8;
@@ -555,10 +556,10 @@ ALSA_OpenAudio(_THIS, SDL_AudioSpec * spec)
             format = SND_PCM_FORMAT_FLOAT_BE;
             break;
         default:
-            format = 0;
+            status = -1;
             break;
         }
-        if (format != 0) {
+        if (status >= 0) {
             status =
                 SDL_NAME(snd_pcm_hw_params_set_format) (pcm_handle,
                                                         hwparams, format);