get_media_devices: Improve usecase example and put it at the beginning

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

diff --git a/utils/libmedia_dev/get_media_devices.h b/utils/libmedia_dev/get_media_devices.h
index c56f8ff..0d3e809 100644 (file)
--- a/utils/libmedia_dev/get_media_devices.h
+++ b/utils/libmedia_dev/get_media_devices.h
@@ -22,6 +22,30 @@
  */
 #define GET_MEDIA_DEVICES_VERSION      0x0101
 
+/*
+ A typical usecase for the above API is:
+
+void start_alsa(char *video_dev) {
+       void *md;
+       char *alsa_playback, *alsa_capture, *p;
+
+       md = discover_media_devices();
+       if (!md)
+               return;
+       alsa_capture = get_first_alsa_cap_device(md, video_dev);
+       alsa_playback = get_first_no_video_out_device(md);
+       if (alsa_capture && alsa_playback)
+               alsa_handler(alsa_playback, alsa_capture);
+       free_media_devices(md);
+}
+
+start_alsa("/dev/video0");
+
+Where alsa_handler() is some function that will need to handle
+ both alsa capture and playback devices.
+*/
+
+
 /**
  * enum device_type - Enumerates the type for each device
  *
@@ -113,25 +137,3 @@ char *get_first_alsa_cap_device(void *opaque, char *v4l_device);
  * device.
  */
 char *get_first_no_video_out_device(void *opaque);
-
-/*
- * A typical usecase for the above API is:
- *
- *     void *md;
- *     unsigned int size = 0;
- *     char *alsa_cap, *alsa_out, *p;
- *     char *video_dev = "/dev/video0";
- *
- *     md = discover_media_devices();
- *     if (md) {
- *             p = strrchr(video_dev, '/');
- *             alsa_cap = get_first_alsa_cap_device(md, p + 1);
- *             alsa_out = get_first_no_video_out_device(md);
- *             if (alsa_cap && alsa_out)
- *                     alsa_handler(alsa_out, alsa_cap);
- *             free_media_devices(md);
- *     }
- *
- * Where alsa_handler() is some function that will need to handle
- * both alsa capture and playback devices.
- */