ASoC: tpa6130a2: Add stereo DAPM path

New DAPM widgets, and paths to enable both channels at the
same time (for stereo output).
With this path the switch time difference can be avoided
between left and right channels.
The original DAPM paths can be still used, if only one of
TPA's output has been connected to a speaker, but for most of
the cases, switching to the stereo path is better.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@nokia.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>

sound/soc/codecs/tpa6130a2.c

@@ -354,20 +354,27 @@ static const struct snd_soc_dapm_widget tpa6130a2_dapm_widgets[] = {
 	SND_SOC_DAPM_PGA_E("TPA6130A2 Right", SND_SOC_NOPM,
 			TPA6130A2_HP_EN_R, 0, NULL, 0, tpa6130a2_pga_event,
 			SND_SOC_DAPM_POST_PMU|SND_SOC_DAPM_POST_PMD),
+	SND_SOC_DAPM_PGA_E("TPA6130A2 Stereo", SND_SOC_NOPM,
+			TPA6130A2_HP_EN_L | TPA6130A2_HP_EN_R, 0, NULL, 0,
+			tpa6130a2_pga_event,
+			SND_SOC_DAPM_POST_PMU|SND_SOC_DAPM_POST_PMD),
 	SND_SOC_DAPM_SUPPLY("TPA6130A2 Enable", SND_SOC_NOPM,
 			0, 0, tpa6130a2_supply_event,
 			SND_SOC_DAPM_POST_PMU|SND_SOC_DAPM_POST_PMD),
 	/* Outputs */
 	SND_SOC_DAPM_OUTPUT("TPA6130A2 Headphone Left"),
 	SND_SOC_DAPM_OUTPUT("TPA6130A2 Headphone Right"),
+	SND_SOC_DAPM_OUTPUT("TPA6130A2 Headphone Stereo"),
 };
 
 static const struct snd_soc_dapm_route audio_map[] = {
 	{"TPA6130A2 Headphone Left", NULL, "TPA6130A2 Left"},
 	{"TPA6130A2 Headphone Right", NULL, "TPA6130A2 Right"},
+	{"TPA6130A2 Headphone Stereo", NULL, "TPA6130A2 Stereo"},
 
 	{"TPA6130A2 Headphone Left", NULL, "TPA6130A2 Enable"},
 	{"TPA6130A2 Headphone Right", NULL, "TPA6130A2 Enable"},
+	{"TPA6130A2 Headphone Stereo", NULL, "TPA6130A2 Enable"},
 };
 
 int tpa6130a2_add_controls(struct snd_soc_codec *codec)