arch/arm/src/stm32: Include needed headers to get stm32_i2s.c compiled

configs/stm32f4discovery/include/board.h: Add SPI DMA pins definitions to get CS43L22 audio DAC working
configs/stm32f4discovery/audio: Add board configuration for CS43L22 audio example
configs/stm32f4discovery:  Update README

arch/arm/src/stm32/stm32_i2s.c

@@ -85,6 +85,10 @@
 #include "up_internal.h"
 #include "up_arch.h"
 
+#include "stm32_dma.h"
+#include "stm32_spi.h"
+#include "stm32_rcc.h"
+
 #if defined(CONFIG_STM32_I2S2) || defined(CONFIG_STM32_I2S3)
 
 /****************************************************************************

arch/arm/src/stm32/stm32_i2s.h

 /************************************************************************************
  * arch/arm/src/stm32/stm32_i2s.h
  *
- *   Copyright (C) 2017 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2017-2018 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without

configs/stm32f4discovery/README.txt

@@ -1188,6 +1188,85 @@ Where <subdir> is one of the sub-directories listed in the next paragraph
 Configuration Sub-directories
 -------------------------
 
+  audio:
+  -----
+
+  This configuration is a variant of the NSH configuration used for
+  demonstrating PCM audio using the CS43L22 stereo DAC/amplifier on board
+  the STM32F4 Discovery and the STM32 I2S DMA interface.  In uses the
+  file player at apps/system/nxplayer.
+
+  The original CS43L22 and STM32 I2S drivers were contribued by Taras
+  Drozdovsky in May of 2017.  The audio configuration was contributed by
+  Alan Carvalho de Assis and derives, in part, from the work of Taras at https://github.com/tdrozdovskiy/CS43L22-Audio-driver.
+
+  Usage instructions from the README file at the location:
+
+  1. Prepare USB flash storage.  This configuration depends on .WAV files
+     provided to the system via a USB flash stick.  There are some sample
+     audio files at https://github.com/tdrozdovskiy/CS43L22-Audio-driver
+     and these steps will put those sample .WAV files onto the USB flash: 
+
+     a. Format the USB flash storage into FAT. For example by next command
+
+       $ mkfs.vfat /dev/sdb1
+
+     b. Create folder /music
+
+       $ mkdir music
+
+     c. Copy files from /audio_samples/ to /music folder of USB flash storage
+
+      $ cp <repo>/audio_samples/* /mnt/media/music/
+
+  2. Example usage CS43L22 Audio driver
+
+    a. Power On or reset the STM32F4 Discovery board.  We can see the Nuttx
+       command line prompt:
+
+      NuttShell (NSH)
+      nsh>
+
+    b. Mount the usb flash device into our file system
+
+      nsh> mount -t vfat /dev/sda/ /mnt/sda
+
+    c. Start the NxPlayer program and Enter the help command to view the list
+       of commands
+
+      nsh> nxplayer
+      NxPlayer version 1.04
+      h for commands, q to exit
+      nxplayer> h
+      NxPlayer commands
+      ================
+        balance d%      : Set balance percentage (< 50% means more left)
+        device devfile  : Specify a preferred audio device
+        h               : Display help for commands
+        help            : Display help for commands
+        mediadir path   : Change the media directory
+        play filename   : Play a media file
+        pause           : Pause playback
+        resume          : Resume playback
+        stop            : Stop playback
+        tone freq secs  : Produce a pure tone
+        q               : Exit NxPlayer
+        quit            : Exit NxPlayer
+        volume d%       : Set volume to level specified
+
+    d. Play the test sample track (cu44k.wav - 44100Hz, 16bit, stereo).
+
+      nxplayer> play cu44k.wav
+
+    e. Set the volume value to 50%.
+
+      nxplayer> volume 50
+
+    f. Stop the current track and play another one
+
+      nxplayer> stop
+      nxplayer> play hn.wav
+
   cxxtest:
   -------
 

configs/stm32f4discovery/audio/defconfig

+# CONFIG_ARCH_FPU is not set
+# CONFIG_NSH_ARGCAT is not set
+# CONFIG_NSH_CMDOPT_HEXDUMP is not set
+# CONFIG_NSH_CMDPARMS is not set
+CONFIG_ARCH="arm"
+CONFIG_ARCH_BOARD="stm32f4discovery"
+CONFIG_ARCH_BOARD_STM32F4_DISCOVERY=y
+CONFIG_ARCH_BUTTONS=y
+CONFIG_ARCH_CHIP_STM32=y
+CONFIG_ARCH_CHIP_STM32F407VG=y
+CONFIG_ARCH_STACKDUMP=y
+CONFIG_AUDIO=y
+CONFIG_AUDIO_CS43L22=y
+CONFIG_AUDIO_CUSTOM_DEV_PATH=y
+CONFIG_AUDIO_EXCLUDE_TONE=y
+CONFIG_BOARD_INITIALIZE=y
+CONFIG_BOARD_LOOPSPERMSEC=16717
+CONFIG_BUILTIN=y
+CONFIG_DISABLE_POLL=y
+CONFIG_DRIVERS_AUDIO=y
+CONFIG_EXAMPLES_NSH=y
+CONFIG_EXAMPLES_NSH_CXXINITIALIZE=y
+CONFIG_FAT_LCNAMES=y
+CONFIG_FAT_LFN=y
+CONFIG_FS_FAT=y
+CONFIG_FS_PROCFS=y
+CONFIG_HAVE_CXX=y
+CONFIG_HAVE_CXXINITIALIZE=y
+CONFIG_I2C=y
+CONFIG_I2C_DRIVER=y
+CONFIG_I2C_POLLED=y
+CONFIG_I2C_RESET=y
+CONFIG_INTELHEX_BINARY=y
+CONFIG_MAX_TASKS=16
+CONFIG_MAX_WDOGPARMS=2
+CONFIG_MM_REGIONS=2
+CONFIG_NFILE_DESCRIPTORS=8
+CONFIG_NFILE_STREAMS=8
+CONFIG_NSH_BUILTIN_APPS=y
+CONFIG_NSH_FILEIOSIZE=512
+CONFIG_NSH_LINELEN=64
+CONFIG_NSH_READLINE=y
+CONFIG_NXPLAYER_DEFAULT_MEDIADIR="/mnt/music"
+CONFIG_PREALLOC_MQ_MSGS=4
+CONFIG_PREALLOC_TIMERS=4
+CONFIG_PREALLOC_WDOGS=16
+CONFIG_RAM_SIZE=114688
+CONFIG_RAM_START=0x20000000
+CONFIG_RAW_BINARY=y
+CONFIG_RR_INTERVAL=200
+CONFIG_SCHED_HPWORK=y
+CONFIG_SCHED_WAITPID=y
+CONFIG_SDCLONE_DISABLE=y
+CONFIG_START_DAY=6
+CONFIG_START_MONTH=12
+CONFIG_START_YEAR=2011
+CONFIG_STM32_DMA1=y
+CONFIG_STM32_DMACAPABLE=y
+CONFIG_STM32_I2C1=y
+CONFIG_STM32_I2S3=y
+CONFIG_STM32_I2S3_TX=y
+CONFIG_STM32_I2S_MCK=y
+CONFIG_STM32_JTAG_SW_ENABLE=y
+CONFIG_STM32_OTGFS=y
+CONFIG_STM32_OTGFS_SOFINTR=y
+CONFIG_STM32_PWR=y
+CONFIG_STM32_SPI1=y
+CONFIG_STM32_SPI3=y
+CONFIG_STM32_SPI_DMA=y
+CONFIG_STM32_USART2=y
+CONFIG_SYSTEM_NXPLAYER=y
+CONFIG_USART2_RXBUFSIZE=128
+CONFIG_USART2_SERIAL_CONSOLE=y
+CONFIG_USART2_TXBUFSIZE=128
+CONFIG_USBHOST=y
+CONFIG_USBHOST_ISOC_DISABLE=y
+CONFIG_USBHOST_MSC=y
+CONFIG_USER_ENTRYPOINT="nsh_main"

configs/stm32f4discovery/include/board.h

 /************************************************************************************
  * configs/stm32f4discovery/include/board.h
  *
- *   Copyright (C) 2012, 2014-2016 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2012, 2014-2016, 2018 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -314,12 +314,26 @@
 #define GPIO_SPI1_MOSI   GPIO_SPI1_MOSI_1
 #define GPIO_SPI1_SCK    GPIO_SPI1_SCK_1
 
+/* SPI DMA -- As used for I2S DMA transfer with the audio configuration */
+
+#define DMACHAN_SPI1_RX DMAMAP_SPI1_RX_1
+#define DMACHAN_SPI1_TX DMAMAP_SPI1_TX_1
+
 /* SPI2 - Test MAX31855 on SPI2 PB10 = SCK, PB14 = MISO */
 
 #define GPIO_SPI2_MISO   GPIO_SPI2_MISO_1
 #define GPIO_SPI2_MOSI   GPIO_SPI2_MOSI_1
 #define GPIO_SPI2_SCK    GPIO_SPI2_SCK_1
 
+/* SPI3 DMA -- As used for I2S DMA transfer with the audio configuration */
+
+#define GPIO_SPI3_MISO   GPIO_SPI3_MISO_1
+#define GPIO_SPI3_MOSI   GPIO_SPI3_MOSI_1
+#define GPIO_SPI3_SCK    GPIO_SPI3_SCK_1
+
+#define DMACHAN_SPI3_RX  DMAMAP_SPI3_RX_1
+#define DMACHAN_SPI3_TX  DMAMAP_SPI3_TX_1
+
 /* I2S3 - CS43L22 configuration uses I2S3 */
 
 #define GPIO_I2S3_SD     GPIO_I2S3_SD_2