Modules: AC97 Codec
Add NULL check in snd_ac97_suspend() and snd_ac97_resume() so that
the caller doesn't have to do it by itself.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
  */
 void snd_ac97_suspend(struct snd_ac97 *ac97)
 {
+       if (! ac97)
+               return;
        if (ac97->build_ops->suspend)
                ac97->build_ops->suspend(ac97);
        snd_ac97_powerdown(ac97);
 {
        unsigned long end_time;
 
+       if (! ac97)
+               return;
+
        if (ac97->bus->ops->reset) {
                ac97->bus->ops->reset(ac97);
                goto  __reset_ready;