spark: add volume control for alsa mixer

libspark/audio_mixer.h

@@ -0,0 +1,37 @@
+/*
+ * audio_mixer.h
+ *
+ * (C) 2012 martii
+ *
+ * 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 program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __AUDIO_MIXER_H__
+#define __AUDIO_MIXER_H__
+#include <alsa/asoundlib.h>
+
+class mixerVolume
+{
+	private:
+		long min, max;
+		snd_mixer_t *handle;
+		snd_mixer_elem_t* elem;
+		snd_mixer_selem_id_t *sid;
+	public:
+		mixerVolume(const char *selem_name, const char *Card, long volume = -1);
+		~mixerVolume(void);
+		bool setVolume(long volume);
+};
+#endif
+