audio: Move hosted audio "codec" drivers into their respective target dirs

They are nearly entirely generic wrappers around ALSA controls, unique
per target, and are ripe for further consolidation.

Change-Id: I05e4a450e3e89e03616906601c4f8fa46200dff5

firmware/target/hosted/agptek/rocker_codec.c

@@ -0,0 +1,93 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ *
+ * Copyright (c) 2018 Marcin Bukat
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+
+#include "config.h"
+#include "audio.h"
+#include "audiohw.h"
+#include "system.h"
+#include "panic.h"
+#include "alsa-controls.h"
+
+static int hw_init = 0;
+
+static long int vol_l_hw = 255;
+static long int vol_r_hw = 255;
+
+static int muted = -1;
+
+void audiohw_mute(int mute)
+{
+    if (!hw_init || muted == mute)
+       return;
+
+    muted = mute;
+
+    if(mute)
+    {
+        long int ps0 = 0;
+        alsa_controls_set_ints("Output Port Switch", 1, &ps0);
+    }
+    else
+    {
+        long int ps2 = 2;
+        alsa_controls_set_ints("Output Port Switch", 1, &ps2);
+    }
+}
+
+void audiohw_preinit(void)
+{
+    alsa_controls_init("default");
+    hw_init = 1;
+#if defined(AUDIOHW_MUTE_ON_STOP) || defined(AUDIOHW_NEEDS_INITIAL_UNMUTE)
+    audiohw_mute(true);  /* Start muted to avoid the POP */
+#else
+    audiohw_mute(false);
+#endif
+}
+
+void audiohw_postinit(void)
+{
+}
+
+void audiohw_close(void)
+{
+    hw_init = 0;
+    muted = -1;
+    alsa_controls_close();
+}
+
+void audiohw_set_frequency(int fsel)
+{
+    (void)fsel;
+}
+
+void audiohw_set_volume(int vol_l, int vol_r)
+{
+    vol_l_hw = -vol_l/5;
+    vol_r_hw = -vol_r/5;
+
+    if (!hw_init)
+       return;
+
+    alsa_controls_set_ints("Left Playback Volume", 1, &vol_l_hw);
+    alsa_controls_set_ints("Right Playback Volume", 1, &vol_r_hw);
+}

firmware/target/hosted/agptek/rocker_codec.h

@@ -0,0 +1,13 @@
+#ifndef __ROCKER_CODEC__
+#define __ROCKER_CODEC__
+
+#define AUDIOHW_CAPS 0
+AUDIOHW_SETTING(VOLUME, "dB", 1, 5, -115*10,  0, -30*10)
+#endif
+
+//#define AUDIOHW_MUTE_ON_STOP
+//#define AUDIOHW_NEEDS_INITIAL_UNMUTE
+
+/* Note:  Due to Kernel bug, we can't use MUTE_ON_PAUSE with backlight fading */
+
+void audiohw_mute(int mute);