boards/esp32-lyrat: Add support for the ES8388 codec

Documentation/platforms/xtensa/esp32/boards/esp32-lyrat/index.rst

@@ -126,6 +126,10 @@ between speakers and headphones is under software control instead of using
 mechanical contacts that would disconnect speakers once a headphone jack is
 inserted.
 
+.. note::
+    The codec implementation on the LyraT board was validated using 16-bit,
+    44.1kHz WAV files. Other configurations might not work as expected.
+
 SD card
 =======
 
@@ -386,6 +390,49 @@ JTAG Header / JP7
 Configurations
 ==============
 
+audio
+-----
+
+This configuration uses the I2S0 peripheral and the ES8388 audio codec
+present on the LyraT board to play an audio file streamed over HTTP
+while connected to a Wi-Fi network.
+
+**Simple HTTP server**
+
+Prepare a PCM-encoded (`.wav`) audio file with 16 bits/sample (sampled at
+44.1kHz). This file must be placed into a folder in a computer that could
+be accessed on the same Wi-Fi network the ESP32 will be connecting to.
+
+Python provides a simple HTTP server. `cd` to the audio file folder on the
+PC and run::
+
+  $ python3 -m http.server
+
+  Serving HTTP on 0.0.0.0 port 8000 (http://0.0.0.0:8000/)
+
+Look for your PC IP address and test playing the prepared audio on your
+browser:
+
+.. figure:: esp32-lyrat-v4.3-audio-config-file.png
+          :align: center
+
+After successfully built and flashed, connect the board to the Wi-Fi network::
+
+  $ nsh> wapi psk wlan0 mypasswd 1
+  $ nsh> wapi essid wlan0 myssid 1
+  $ nsh> renew wlan0
+
+Once connected, open NuttX's player and play the file according to its file
+name and the IP address of the HTTP server (For example `tones.wav` and
+`192.168.1.239:8000`, respectively)::
+
+  $ nsh> nxplayer
+  $ nxplayer> play http://192.168.1.239:8000/tones.wav
+
+.. note::
+    The codec implementation on the LyraT board was validated using 16-bit,
+    44.1kHz WAV files. Other configurations might not work as expected.
+
 nsh
 ---
 

boards/xtensa/esp32/common/include/esp32_es8388.h

@@ -0,0 +1,90 @@
+/****************************************************************************
+ * boards/xtensa/esp32/common/include/esp32_es8388.h
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.  The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+#ifndef __BOARDS_XTENSA_ESP32_COMMON_INCLUDE_ESP32_ES8388_H
+#define __BOARDS_XTENSA_ESP32_COMMON_INCLUDE_ESP32_ES8388_H
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Type Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Types
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+#ifdef __cplusplus
+#define EXTERN extern "C"
+extern "C"
+{
+#else
+#define EXTERN extern
+#endif
+
+/****************************************************************************
+ * Inline Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: esp32_es8388_initialize
+ *
+ * Description:
+ *   This function is called by platform-specific, setup logic to configure
+ *   and register the ES8388 device.  This function will register the driver
+ *   as /dev/audio/pcm[x] where x is determined by the I2S port number.
+ *
+ * Input Parameters:
+ *   i2c_port  - The I2C port used for the device
+ *   i2c_addr  - The I2C address used by the device
+ *   i2c_freq  - The I2C frequency used for the device
+ *   i2s_port  - The I2S port used for the device
+ *
+ * Returned Value:
+ *   Zero is returned on success.  Otherwise, a negated errno value is
+ *   returned to indicate the nature of the failure.
+ *
+ ****************************************************************************/
+
+int esp32_es8388_initialize(int i2c_port, uint8_t i2c_addr, int i2c_freq,
+                            int i2s_port);
+
+#undef EXTERN
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __BOARDS_XTENSA_ESP32_COMMON_INCLUDE_ESP32_ES8388_H */

boards/xtensa/esp32/common/src/Make.defs

@@ -48,6 +48,10 @@ ifeq ($(CONFIG_AUDIO_CS4344),y)
   CSRCS += esp32_cs4344.c
 endif
 
+ifeq ($(CONFIG_AUDIO_ES8388),y)
+  CSRCS += esp32_es8388.c
+endif
+
 ifeq ($(CONFIG_I2CMULTIPLEXER_TCA9548A),y)
   CSRCS += esp32_tca9548a.c
 endif

boards/xtensa/esp32/common/src/esp32_board_i2sdev.c

@@ -37,8 +37,8 @@
 
 #include "esp32_i2s.h"
 
-#if defined(CONFIG_ESP32_I2S0) && !defined(CONFIG_AUDIO_CS4344) || \
+#if defined(CONFIG_ESP32_I2S0) && !defined(CONFIG_AUDIO_CS4344) && \
-    defined(CONFIG_ESP32_I2S1)
+!defined(CONFIG_AUDIO_ES8388) || defined(CONFIG_ESP32_I2S1)
 
 /****************************************************************************
  * Public Functions
@@ -111,4 +111,5 @@ int board_i2sdev_initialize(int port)
   return ret;
 }
 
-#endif /* CONFIG_ESP32_I2S0 && !CONFIG_AUDIO_CS4344 || CONFIG_ESP32_I2S1 */
+#endif /* CONFIG_ESP32_I2S0 && !CONFIG_AUDIO_CS4344 && \    *
+        * !CONFIG_AUDIO_ES8388 || CONFIG_ESP32_I2S1         */

boards/xtensa/esp32/common/src/esp32_es8388.c

@@ -0,0 +1,193 @@
+/****************************************************************************
+ * boards/xtensa/esp32/common/src/esp32_es8388.c
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.  The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <stdbool.h>
+#include <stdio.h>
+#include <debug.h>
+#include <assert.h>
+#include <errno.h>
+
+#include <nuttx/irq.h>
+#include <nuttx/audio/i2s.h>
+#include <nuttx/audio/pcm.h>
+#include <nuttx/audio/es8388.h>
+#include <nuttx/i2c/i2c_master.h>
+#include <nuttx/kmalloc.h>
+
+#include <arch/board/board.h>
+
+#include "esp32_board_i2c.h"
+#include "esp32_i2c.h"
+#include "esp32_i2s.h"
+
+#if defined(CONFIG_ESP32_I2S) && defined(CONFIG_AUDIO_ES8388)
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: esp32_es8388_initialize
+ *
+ * Description:
+ *   This function is called by platform-specific, setup logic to configure
+ *   and register the ES8388 device.  This function will register the driver
+ *   as /dev/audio/pcm[x] where x is determined by the I2S port number.
+ *
+ * Input Parameters:
+ *   i2c_port  - The I2C port used for the device
+ *   i2c_addr  - The I2C address used by the device
+ *   i2c_freq  - The I2C frequency used for the device
+ *   i2s_port  - The I2S port used for the device
+ *
+ * Returned Value:
+ *   Zero is returned on success.  Otherwise, a negated errno value is
+ *   returned to indicate the nature of the failure.
+ *
+ ****************************************************************************/
+
+int esp32_es8388_initialize(int i2c_port, uint8_t i2c_addr, int i2c_freq,
+                            int i2s_port)
+{
+  struct audio_lowerhalf_s *es8388;
+  struct audio_lowerhalf_s *pcm;
+  struct es8388_lower_s *lower;
+  struct i2s_dev_s *i2s;
+  struct i2c_master_s *i2c;
+  static bool initialized = false;
+  char devname[12];
+  int ret;
+
+  audinfo("i2s_port %d\ni2c_port %d, i2c_addr %d, i2c_freq %d\n",
+          i2s_port, i2c_port, i2c_addr, i2c_freq);
+  DEBUGASSERT(i2s_port >= 0 && i2s_port <= 1 && \
+              i2c_port >= 0 && i2c_port <= 1);
+
+  /* Have we already initialized?  Since we never uninitialize we must
+   * prevent multiple initializations.  This is necessary, for example,
+   * when the touchscreen example is used as a built-in application in
+   * NSH and can be called numerous time.  It will attempt to initialize
+   * each time.
+   */
+
+  if (!initialized)
+    {
+      /* Get an instance of the I2S interface for the ES8388 data channel */
+
+      i2s = esp32_i2sbus_initialize(i2s_port);
+      if (i2s == NULL)
+        {
+          auderr("ERROR: Failed to initialize I2S%d\n", i2s_port);
+          ret = -ENODEV;
+          goto errout;
+        }
+
+      i2c = esp32_i2cbus_initialize(i2c_port);
+      if (i2c == NULL)
+        {
+          auderr("ERROR: Failed to initialize I2C%d\n", i2c_port);
+          ret = -ENODEV;
+          goto errout;
+        }
+
+      /* Check wheter to enable a simple character driver that supports I2S
+       * transfers via a read() and write().  The intent of this driver is to
+       * support I2S testing.  It is not an audio driver but does conform to
+       * some of the buffer management heuristics of an audio driver.  It is
+       * not suitable for use in any real driver application in its current
+       * form. The i2schar driver will be initialized at /dev/i2schar0
+       */
+
+#ifdef CONFIG_AUDIO_I2SCHAR
+      ret = i2schar_register(i2s, 0);
+      if (ret < 0)
+        {
+          auderr("ERROR: i2schar_register failed: %d\n", ret);
+          goto errout;
+        }
+#endif
+
+      /* Now we can use this I2S interface to initialize the ES8388 which
+       * will return an audio interface.
+       */
+
+      lower = (FAR struct es8388_lower_s *)
+        kmm_zalloc(sizeof(struct es8388_lower_s));
+
+      lower->address   = i2c_addr,
+      lower->frequency = i2c_freq,
+
+      es8388 = es8388_initialize(i2c, i2s, lower);
+      if (es8388 == NULL)
+        {
+          auderr("ERROR: Failed to initialize the ES8388\n");
+          ret = -ENODEV;
+          goto errout;
+        }
+
+      /* Now we can embed the ES8388/I2S conglomerate into a PCM decoder
+       * instance so that we will have a PCM front end for the the ES8388
+       * driver.
+       */
+
+      pcm = pcm_decode_initialize(es8388);
+      if (pcm == NULL)
+        {
+          auderr("ERROR: Failed create the PCM decoder\n");
+          ret = -ENODEV;
+          goto errout;
+        }
+
+      /* Create a device name */
+
+      snprintf(devname, 12, "pcm%d",  i2s_port);
+
+      /* Finally, we can register the PCM/ES8388/I2S audio device. */
+
+      ret = audio_register(devname, pcm);
+      if (ret < 0)
+        {
+          auderr("ERROR: Failed to register /dev/%s device: %d\n",
+                 devname, ret);
+          goto errout;
+        }
+
+      /* Now we are initialized */
+
+      initialized = true;
+    }
+
+  return OK;
+
+errout:
+  return ret;
+}
+
+#endif /* CONFIG_ESP32_I2S && CONFIG_AUDIO_ES8388 */

boards/xtensa/esp32/esp32-lyrat/configs/audio/defconfig

@@ -0,0 +1,127 @@
+#
+# This file is autogenerated: PLEASE DO NOT EDIT IT.
+#
+# You can use "make menuconfig" to make any modifications to the installed .config file.
+# You can then do "make savedefconfig" to generate a new defconfig file that includes your
+# modifications.
+#
+# CONFIG_ARCH_LEDS is not set
+# CONFIG_ESP32_I2S0_RX is not set
+# CONFIG_NDEBUG is not set
+# CONFIG_NSH_ARGCAT is not set
+# CONFIG_NSH_CMDOPT_HEXDUMP is not set
+# CONFIG_NSH_CMDPARMS is not set
+CONFIG_ALLOW_BSD_COMPONENTS=y
+CONFIG_ARCH="xtensa"
+CONFIG_ARCH_BOARD="esp32-lyrat"
+CONFIG_ARCH_BOARD_COMMON=y
+CONFIG_ARCH_BOARD_ESP32_LYRAT=y
+CONFIG_ARCH_CHIP="esp32"
+CONFIG_ARCH_CHIP_ESP32=y
+CONFIG_ARCH_CHIP_ESP32WROVER=y
+CONFIG_ARCH_INTERRUPTSTACK=4096
+CONFIG_ARCH_STACKDUMP=y
+CONFIG_ARCH_XTENSA=y
+CONFIG_AUDIO=y
+CONFIG_AUDIOUTILS_MMLPARSER_LIB=y
+CONFIG_AUDIO_BUFFER_NUMBYTES=4096
+CONFIG_AUDIO_ES8388=y
+CONFIG_AUDIO_EXCLUDE_FFORWARD=y
+CONFIG_AUDIO_EXCLUDE_TONE=y
+CONFIG_AUDIO_I2S=y
+CONFIG_AUDIO_I2SCHAR=y
+CONFIG_AUDIO_NUM_BUFFERS=4
+CONFIG_BOARDCTL_ROMDISK=y
+CONFIG_BOARD_LOOPSPERMSEC=16717
+CONFIG_BUILTIN=y
+CONFIG_DEBUG_NOOPT=y
+CONFIG_DEFAULT_TASK_STACKSIZE=4096
+CONFIG_DEV_URANDOM=y
+CONFIG_DRIVERS_AUDIO=y
+CONFIG_DRIVERS_IEEE80211=y
+CONFIG_DRIVERS_WIRELESS=y
+CONFIG_ESP32_I2C0=y
+CONFIG_ESP32_I2C0_SCLPIN=23
+CONFIG_ESP32_I2C0_SDAPIN=18
+CONFIG_ESP32_I2S0=y
+CONFIG_ESP32_I2S0_BCLKPIN=5
+CONFIG_ESP32_I2S0_DATA_BIT_WIDTH_16BIT=y
+CONFIG_ESP32_I2S0_DOUTPIN=26
+CONFIG_ESP32_I2S0_MCLK=y
+CONFIG_ESP32_I2S0_WSPIN=25
+CONFIG_ESP32_I2S=y
+CONFIG_ESP32_SPIFLASH=y
+CONFIG_ESP32_STORAGE_MTD_SIZE=0x80000
+CONFIG_ESP32_UART0=y
+CONFIG_ESP32_WIFI=y
+CONFIG_ESP32_WIFI_SAVE_PARAM=y
+CONFIG_EXAMPLES_I2SCHAR=y
+CONFIG_EXAMPLES_I2SCHAR_TX=y
+CONFIG_EXAMPLES_I2SCHAR_TXBUFFERS=2
+CONFIG_EXAMPLES_I2SCHAR_TXSTACKSIZE=2048
+CONFIG_EXAMPLES_ROMFS=y
+CONFIG_FS_PROCFS=y
+CONFIG_FS_ROMFS=y
+CONFIG_HAVE_CXX=y
+CONFIG_HAVE_CXXINITIALIZE=y
+CONFIG_I2C=y
+CONFIG_I2S_DMADESC_NUM=4
+CONFIG_IDLETHREAD_STACKSIZE=3072
+CONFIG_INIT_ENTRYPOINT="nsh_main"
+CONFIG_INTELHEX_BINARY=y
+CONFIG_IOB_NBUFFERS=24
+CONFIG_IOB_THROTTLE=0
+CONFIG_MM_CIRCBUF=y
+CONFIG_MM_REGIONS=3
+CONFIG_NAME_MAX=48
+CONFIG_NETDB_DNSCLIENT=y
+CONFIG_NETDB_DNSCLIENT_NAMESIZE=64
+CONFIG_NETDEV_LATEINIT=y
+CONFIG_NETDEV_PHY_IOCTL=y
+CONFIG_NETDEV_WIRELESS_IOCTL=y
+CONFIG_NETINIT_WAPI_ALG=1
+CONFIG_NETUTILS_IPERF=y
+CONFIG_NETUTILS_TELNETD=y
+CONFIG_NET_BROADCAST=y
+CONFIG_NET_ETH_PKTSIZE=1518
+CONFIG_NET_ICMP=y
+CONFIG_NET_ICMP_SOCKET=y
+CONFIG_NET_NACTIVESOCKETS=32
+CONFIG_NET_STATISTICS=y
+CONFIG_NET_TCP=y
+CONFIG_NET_TCP_DELAYED_ACK=y
+CONFIG_NET_TCP_WRITE_BUFFERS=y
+CONFIG_NET_UDP=y
+CONFIG_NSH_ARCHINIT=y
+CONFIG_NSH_BUILTIN_APPS=y
+CONFIG_NSH_FILEIOSIZE=512
+CONFIG_NSH_LINELEN=300
+CONFIG_NSH_READLINE=y
+CONFIG_NXPLAYER_HTTP_STREAMING_SUPPORT=y
+CONFIG_NXPLAYER_PLAYTHREAD_STACKSIZE=4096
+CONFIG_POSIX_SPAWN_DEFAULT_STACKSIZE=2048
+CONFIG_PREALLOC_TIMERS=4
+CONFIG_PTHREAD_MUTEX_TYPES=y
+CONFIG_PTHREAD_STACK_DEFAULT=2048
+CONFIG_RAM_SIZE=114688
+CONFIG_RAM_START=0x20000000
+CONFIG_RR_INTERVAL=200
+CONFIG_SCHED_HPWORK=y
+CONFIG_SCHED_HPWORKSTACKSIZE=2048
+CONFIG_SCHED_LPWORK=y
+CONFIG_SCHED_WAITPID=y
+CONFIG_SIG_DEFAULT=y
+CONFIG_SPI=y
+CONFIG_START_DAY=6
+CONFIG_START_MONTH=12
+CONFIG_START_YEAR=2011
+CONFIG_SYSTEM_DHCPC_RENEW=y
+CONFIG_SYSTEM_NSH=y
+CONFIG_SYSTEM_NXPLAYER=y
+CONFIG_SYSTEM_PING=y
+CONFIG_TELNET_CHARACTER_MODE=y
+CONFIG_TLS_TASK_NELEM=4
+CONFIG_UART0_SERIAL_CONSOLE=y
+CONFIG_WIRELESS=y
+CONFIG_WIRELESS_WAPI=y
+CONFIG_WIRELESS_WAPI_CMDTOOL=y

boards/xtensa/esp32/esp32-lyrat/configs/wapi/defconfig

@@ -17,10 +17,17 @@ CONFIG_ARCH_BOARD_ESP32_LYRAT=y
 CONFIG_ARCH_CHIP="esp32"
 CONFIG_ARCH_CHIP_ESP32=y
 CONFIG_ARCH_CHIP_ESP32WROVER=y
+CONFIG_ARCH_INTERRUPTSTACK=2048
 CONFIG_ARCH_STACKDUMP=y
 CONFIG_ARCH_XTENSA=y
 CONFIG_BOARD_LOOPSPERMSEC=16717
 CONFIG_BUILTIN=y
+CONFIG_DEBUG_ASSERTIONS=y
+CONFIG_DEBUG_FEATURES=y
+CONFIG_DEBUG_FULLOPT=y
+CONFIG_DEBUG_SYMBOLS=y
+CONFIG_DEFAULT_TASK_STACKSIZE=4096
+CONFIG_DEV_URANDOM=y
 CONFIG_DRIVERS_IEEE80211=y
 CONFIG_DRIVERS_WIRELESS=y
 CONFIG_ESP32_SPIFLASH=y
@@ -30,28 +37,34 @@ CONFIG_ESP32_UART0=y
 CONFIG_ESP32_WIFI=y
 CONFIG_ESP32_WIFI_SAVE_PARAM=y
 CONFIG_FS_PROCFS=y
-CONFIG_HAVE_CXX=y
-CONFIG_HAVE_CXXINITIALIZE=y
 CONFIG_IDLETHREAD_STACKSIZE=3072
 CONFIG_INIT_ENTRYPOINT="nsh_main"
-CONFIG_INIT_STACKSIZE=3072
 CONFIG_INTELHEX_BINARY=y
 CONFIG_MM_REGIONS=3
 CONFIG_NAME_MAX=48
 CONFIG_NETDB_DNSCLIENT=y
+CONFIG_NETDB_DNSCLIENT_NAMESIZE=64
 CONFIG_NETDEV_LATEINIT=y
 CONFIG_NETDEV_PHY_IOCTL=y
 CONFIG_NETDEV_WIRELESS_IOCTL=y
+CONFIG_NETUTILS_IPERF=y
+CONFIG_NETUTILS_TELNETD=y
 CONFIG_NET_BROADCAST=y
+CONFIG_NET_ETH_PKTSIZE=1518
 CONFIG_NET_ICMP=y
 CONFIG_NET_ICMP_SOCKET=y
+CONFIG_NET_NACTIVESOCKETS=32
+CONFIG_NET_STATISTICS=y
 CONFIG_NET_TCP=y
+CONFIG_NET_TCP_DELAYED_ACK=y
+CONFIG_NET_TCP_WRITE_BUFFERS=y
 CONFIG_NET_UDP=y
 CONFIG_NSH_ARCHINIT=y
 CONFIG_NSH_BUILTIN_APPS=y
 CONFIG_NSH_FILEIOSIZE=512
-CONFIG_NSH_LINELEN=64
+CONFIG_NSH_LINELEN=300
 CONFIG_NSH_READLINE=y
+CONFIG_POSIX_SPAWN_DEFAULT_STACKSIZE=2048
 CONFIG_PREALLOC_TIMERS=4
 CONFIG_PTHREAD_MUTEX_TYPES=y
 CONFIG_RAM_SIZE=114688
@@ -62,15 +75,17 @@ CONFIG_SCHED_WAITPID=y
 CONFIG_SIG_DEFAULT=y
 CONFIG_SPI=y
 CONFIG_SPIFFS_NAME_MAX=48
+CONFIG_STACK_COLORATION=y
 CONFIG_START_DAY=6
 CONFIG_START_MONTH=12
 CONFIG_START_YEAR=2011
 CONFIG_SYSTEM_DHCPC_RENEW=y
 CONFIG_SYSTEM_NSH=y
 CONFIG_SYSTEM_PING=y
+CONFIG_SYSTEM_STACKMONITOR=y
+CONFIG_TELNET_CHARACTER_MODE=y
 CONFIG_TLS_TASK_NELEM=4
 CONFIG_UART0_SERIAL_CONSOLE=y
 CONFIG_WIRELESS=y
 CONFIG_WIRELESS_WAPI=y
 CONFIG_WIRELESS_WAPI_CMDTOOL=y
-CONFIG_WIRELESS_WAPI_STACKSIZE=4096

boards/xtensa/esp32/esp32-lyrat/include/board.h

@@ -56,13 +56,14 @@
 
 /* ES8388 CODEC */
 
-#define ES8388_CCLK       23
+#define ES8388_I2C_CCLK       23     /* SCL */
-#define ES8388_CDATA      18
+#define ES8388_I2C_CDATA      18     /* SDA */
-#define ES8388_MCLK       0
+
-#define ES8388_SCLK       5
+#define ES8388_I2S_MCLK       0      /* Master clock */
-#define ES8388_LRCK       25
+#define ES8388_I2S_SCLK       5      /* Audio data bit clock */
-#define ES8388_DSDIN      26
+#define ES8388_I2S_LRCK       25     /* Audio data left and right clock */
-#define ES8388_ASDOUT     35
+#define ES8388_I2S_DSDIN      26     /* DAC audio data (to speakers) */
+#define ES8388_I2S_ASDOUT     35     /* ADC audio data (from microphone) */
 
 /* LED definitions **********************************************************/
 
@@ -76,4 +77,11 @@
 #define BOARD_NGPIOIN     1 /* Amount of GPIO Input without Interruption */
 #define BOARD_NGPIOINT    1 /* Amount of GPIO Input w/ Interruption pins */
 
+/* Peripherals definitions **************************************************/
+
+/* ES8388 CODEC */
+
+#define ES8388_I2C_FREQ       400000
+#define ES8388_I2C_ADDR       0x10
+
 #endif /* __BOARDS_XTENSA_ESP32_ESP32_LYRAT_INCLUDE_BOARD_H */

boards/xtensa/esp32/esp32-lyrat/src/esp32-lyrat.h

@@ -39,6 +39,10 @@
 
 #define GPIO_LED1  22
 
+/* Audio Amplifier */
+
+#define SPEAKER_ENABLE_GPIO   21
+
 /* Buttons */
 
 /* As BOOT_BUTTON shares pins with I2S and the SD card it cannot be used
@@ -92,6 +96,52 @@
 
 int esp32_bringup(void);
 
+/****************************************************************************
+ * Name: esp32_es8388_initialize
+ *
+ * Description:
+ *   This function is called by platform-specific, setup logic to configure
+ *   and register the ES8388 device.  This function will register the driver
+ *   as /dev/audio/pcm[x] where x is determined by the I2S port number.
+ *
+ * Input Parameters:
+ *   i2c_port  - The I2C port used for the device
+ *   i2c_addr  - The I2C address used by the device
+ *   i2c_freq  - The I2C frequency used for the device
+ *   i2s_port  - The I2S port used for the device
+ *
+ * Returned Value:
+ *   Zero is returned on success.  Otherwise, a negated errno value is
+ *   returned to indicate the nature of the failure.
+ *
+ ****************************************************************************/
+
+int esp32_es8388_initialize(int i2c_port, uint8_t i2c_addr, int i2c_freq,
+                            int i2s_port);
+
+/****************************************************************************
+ * Name: board_i2sdev_initialize
+ *
+ * Description:
+ *   This function is called by platform-specific, setup logic to configure
+ *   and register the generic I2S audio driver.  This function will register
+ *   the driver as /dev/audio/pcm[x] where x is determined by the I2S port
+ *   number.
+ *
+ * Input Parameters:
+ *   port  - The I2S port used for the device
+ *
+ * Returned Value:
+ *   Zero is returned on success.  Otherwise, a negated errno value is
+ *   returned to indicate the nature of the failure.
+ *
+ ****************************************************************************/
+
+#if defined CONFIG_ESP32_I2S0 && !defined CONFIG_AUDIO_ES8388 || \
+    defined CONFIG_ESP32_I2S1
+int board_i2sdev_initialize(int port);
+#endif
+
 /****************************************************************************
  * Name: esp32_mmcsd_initialize
  *

boards/xtensa/esp32/esp32-lyrat/src/esp32_bringup.c

@@ -40,6 +40,8 @@
 #include <nuttx/fs/fs.h>
 #include <nuttx/himem/himem.h>
 
+#include "esp32_i2c.h"
+#include "esp32_gpio.h"
 #include "esp32_partition.h"
 
 #include <arch/board/board.h>
@@ -76,6 +78,10 @@
 #  include "esp32_board_i2c.h"
 #endif
 
+#ifdef CONFIG_ESP32_I2S
+#  include "esp32_i2s.h"
+#endif
+
 #ifdef CONFIG_SENSORS_BMP180
 #  include "esp32_bmp180.h"
 #endif
@@ -331,6 +337,54 @@ int esp32_bringup(void)
 
 #endif
 
+#ifdef CONFIG_ESP32_I2S
+
+#ifdef CONFIG_ESP32_I2S0
+
+  /* Configure I2S0 */
+
+#ifdef CONFIG_AUDIO_ES8388
+
+  /* Configure ES8388 audio on I2C0 and I2S0 */
+
+  esp32_configgpio(SPEAKER_ENABLE_GPIO, OUTPUT);
+  esp32_gpiowrite(SPEAKER_ENABLE_GPIO, true);
+
+  ret = esp32_es8388_initialize(ESP32_I2C0, ES8388_I2C_ADDR,
+                                ES8388_I2C_FREQ, ESP32_I2S0);
+  if (ret != OK)
+    {
+      syslog(LOG_ERR, "Failed to initialize ES8388 audio: %d\n", ret);
+    }
+#else
+
+  /* Configure I2S generic audio on I2S0 */
+
+  ret = board_i2sdev_initialize(ESP32_I2S0);
+  if (ret < 0)
+    {
+      syslog(LOG_ERR, "Failed to initialize I2S%d driver: %d\n",
+             CONFIG_ESP32_I2S0, ret);
+    }
+#endif /* CONFIG_AUDIO_ES8388 */
+
+#endif  /* CONFIG_ESP32_I2S0 */
+
+#ifdef CONFIG_ESP32_I2S1
+
+  /* Configure I2S generic audio on I2S1 */
+
+  ret = board_i2sdev_initialize(ESP32_I2S1);
+  if (ret < 0)
+    {
+      syslog(LOG_ERR, "Failed to initialize I2S%d driver: %d\n",
+             CONFIG_ESP32_I2S0, ret);
+    }
+
+#endif  /* CONFIG_ESP32_I2S1 */
+
+#endif /* CONFIG_ESP32_I2S */
+
 #ifdef CONFIG_SENSORS_BMP180
   /* Try to register BMP180 device in I2C0 */