msm: audio: qdsp5v2: Fix issues with LPA playback volume after call

- LPA audio plays with higher volume after voice call.
- In LPA driver POPP gain is always set to unity. This should only
reset when switching from NON-HLB to HLB device.
- Add attribute to maintain the previous state to set POPP gain only
in case of device switch from NON-HLB to HLB.

Change-Id: Id125d8f81b5b423ffbfd6dee551e9061e13a500e
CRs-Fixed: 321780
Signed-off-by: Vinay Vaka <vvaka@codeaurora.org>

arch/arm/mach-msm/include/mach/qdsp5v2/codec_utils.h

@@ -1,4 +1,4 @@
-/* Copyright (c) 2010, Code Aurora Forum. All rights reserved.
+/* Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -109,6 +109,7 @@ struct audio {
 	uint32_t read_ptr_offset;
 	int16_t source;
 
+	int16_t prev_source;
 #ifdef CONFIG_HAS_EARLYSUSPEND
 	struct audio_suspend_ctl suspend_ctl;
 #endif

arch/arm/mach-msm/qdsp5v2/audio_lpa.c

@@ -2,7 +2,7 @@
  *
  * Copyright (C) 2008 Google, Inc.
  * Copyright (C) 2008 HTC Corporation
- * Copyright (c) 2009-2010, Code Aurora Forum. All rights reserved.
+ * Copyright (c) 2009-2011, Code Aurora Forum. All rights reserved.
  *
  * This software is licensed under the terms of the GNU General Public
  * License version 2, as published by the Free Software Foundation, and
@@ -193,6 +193,8 @@ static void lpa_listner(u32 evt_id, union auddev_evt_data *evt_payload,
 					AUDPP_CMD_CFG_DEV_MIXER_ID_4,
 					&audio->vol_pan,
 					COPP);
+				/* after applying on COPP */
+				if(audio->prev_source == AUDPP_MIXER_NONHLB) {
 					/*restore the POPP gain to 0x2000
 					this is needed to avoid use cases
 					where POPP volume is lowered during
@@ -205,9 +207,14 @@ static void lpa_listner(u32 evt_id, union auddev_evt_data *evt_payload,
 					audpp_dsp_set_vol_pan(
 						audio->dec_id,
 						&audio->vol_pan, POPP);
-			} else if (audio->source & AUDPP_MIXER_NONHLB)
+					audio->prev_source = AUDPP_MIXER_HLB;
+				}
+			} else if (audio->source & AUDPP_MIXER_NONHLB) {
+				/* after applying on POPP */
+				audio->prev_source = AUDPP_MIXER_NONHLB;
 				audpp_dsp_set_vol_pan(
 					audio->dec_id, &audio->vol_pan, POPP);
+			}
 			if (audio->device_switch == DEVICE_SWITCH_STATE_READY) {
 				audio->wflush = 1;
 				audio->device_switch =