V4L/DVB: cx18: overhaul ALSA PCM device handling so it works

Add code so that the PCM ALSA device actually works, and update the
cx18-streams mechanism so that it passes the data off to the cx18-alsa module.

This work was sponsored by ONELAN Limited.

Signed-off-by: Devin Heitmueller <dheitmueller@kernellabs.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/video/cx18/cx18-alsa-pcm.h b/drivers/media/video/cx18/cx18-alsa-pcm.h
index ff47a1e..325662c 100644
--- a/drivers/media/video/cx18/cx18-alsa-pcm.h
+++ b/drivers/media/video/cx18/cx18-alsa-pcm.h
@@ -21,3 +21,7 @@
  */
 
 int __init snd_cx18_pcm_create(struct snd_cx18_card *cxsc);
+
+/* Used by cx18-mailbox to announce the PCM data to the module */
+void cx18_alsa_announce_pcm_data(struct snd_cx18_card *card, u8 *pcm_data,
+				 size_t num_bytes);