From 49d6ff6ac4b81b5b7ac9c506c40a8d420f46e197 Mon Sep 17 00:00:00 2001
From: Jeroen Domburg <git@j0h.nl>
Date: Thu, 9 Nov 2017 15:25:43 -0800
Subject: [PATCH] Disable amp if no sound

---
 components/tme-esp32/snd.c | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/components/tme-esp32/snd.c b/components/tme-esp32/snd.c
index ff62860..79f33c0 100644
--- a/components/tme-esp32/snd.c
+++ b/components/tme-esp32/snd.c
@@ -12,9 +12,13 @@ static QueueHandle_t soundQueue;
 //powers of 2 plzthx
 #define BUFLEN 2048
 
+#define IO_AMP_DIS 2
+
 static uint8_t buf[BUFLEN];
 static volatile int wp=256, rp=0;
 
+static int ampPowerTimeout=0;
+
 static int bufLen() {
 	return (wp-rp)&(BUFLEN-1);
 }
@@ -55,12 +59,16 @@ int sndPush(uint8_t *data, int volume) {
 			wp++;
 			if (wp>=BUFLEN) wp=0;
 		}
+		gpio_set_level(IO_AMP_DIS, 0);
+		ampPowerTimeout=10;
 	} else {
 		//muted
 		for (int i=0; i<370; i++) {
 			buf[wp++]=128;
 			if (wp>=BUFLEN) wp=0;
 		}
+		ampPowerTimeout--;
+		if (ampPowerTimeout==0) gpio_set_level(IO_AMP_DIS, 1);
 	}
 	return 1;
 }
@@ -81,6 +89,15 @@ void sndInit() {
 	i2s_set_dac_mode(I2S_DAC_CHANNEL_LEFT_EN);
 	i2s_set_sample_rates(0, cfg.sample_rate);
 
+	gpio_config_t io_conf_amp={
+		.intr_type=GPIO_INTR_DISABLE,
+		.mode=GPIO_MODE_OUTPUT,
+		.pull_up_en=1,
+		.pin_bit_mask=(1<<IO_AMP_DIS) //Amp enable line
+	};
+	gpio_config(&io_conf_amp);
+
+
 #if 1
 	//I2S enables *both* DAC channels; we only need DAC2. DAC1 is connected to the select button.
 	CLEAR_PERI_REG_MASK(RTC_IO_PAD_DAC1_REG, RTC_IO_PDAC1_DAC_XPD_FORCE_M);