git-svn-id: svn://svn.code.sf.net/p/chibios/svn/branches/kernel_3_dev@6749 35acf78f-673a-0410-8e92-d51de3d6d3f4

os/hal/include/i2s.h

@@ -163,7 +163,7 @@ extern "C" {
   void i2sStart(I2SDriver *i2sp, const I2SConfig *config);
   void i2sStop(I2SDriver *i2sp);
   void i2sStartExchange(I2SDriver *i2sp);
-  void i2sStopTransfer(I2SDriver *i2sp);
+  void i2sStopExchange(I2SDriver *i2sp);
 #ifdef __cplusplus
 }
 #endif

os/hal/ports/STM32/LLD/SPIv1/i2s_lld.c

@@ -419,14 +419,22 @@ void i2s_lld_start_exchange(I2SDriver *i2sp) {
  */
 void i2s_lld_stop_exchange(I2SDriver *i2sp) {
 
-  /* Stop DMAs.*/
-  if (NULL != i2sp->dmatx)
+  /* Stop TX DMA, if enabled.*/
+  if (NULL != i2sp->dmatx) {
     dmaStreamDisable(i2sp->dmatx);
+
+    /* From the RM: To switch off the I2S, by clearing I2SE, it is mandatory
+       to wait for TXE = 1 and BSY = 0.*/
+    while ((i2sp->spi->SR & (SPI_SR_TXE | SPI_SR_BSY)) != SPI_SR_TXE)
+      ;
+  }
+
+  /* Stop SPI/I2S peripheral.*/
+  i2sp->spi->I2SCFGR &= ~SPI_I2SCFGR_I2SE;
+
+  /* Stop RX DMA, if enabled.*/
   if (NULL != i2sp->dmarx)
     dmaStreamDisable(i2sp->dmarx);
-
-  /* Stop transfer.*/
-  i2sp->spi->I2SCFGR &= ~SPI_I2SCFGR_I2SE;
 }
 
 #endif /* HAL_USE_I2S */

testhal/STM32F4xx/I2S/main.c

@@ -17,6 +17,28 @@
 #include "ch.h"
 #include "hal.h"
 
+#define I2S_BUF_SIZE            256
+
+static uint16_t i2s_rx_buf[I2S_BUF_SIZE];
+
+static void i2scallback(I2SDriver *i2sp, size_t offset, size_t n);
+
+static const I2SConfig i2scfg = {
+  NULL,
+  i2s_rx_buf,
+  I2S_BUF_SIZE,
+  i2scallback,
+  0,
+  16
+};
+
+static void i2scallback(I2SDriver *i2sp, size_t offset, size_t n) {
+
+  (void)i2sp;
+  (void)offset;
+  (void)n;
+}
+
 /*
  * Application entry point.
  */
@@ -33,9 +55,22 @@ int main(void) {
   chSysInit();
 
   /*
-   * Normal main() thread activity, in this demo it does nothing.
+   * Starting and configuring the I2S driver 2.
+   */
+  i2sStart(&I2SD2, &i2scfg);
+
+  /*
+   * Starting continuous I2S transfer.
+   */
+  i2sStartExchange(&I2SD2);
+
+  /*
+   * Normal main() thread activity, if the button is pressed then the I2s
+   * transfer is stopped.
    */
   while (TRUE) {
+    if (palReadPad(GPIOA, GPIOA_BUTTON))
+      i2sStopExchange(&I2SD2);
     chThdSleepMilliseconds(500);
   }
   return 0;

testhal/STM32F4xx/I2S/mcuconf.h

@@ -54,7 +54,7 @@
 #define STM32_MCO1PRE                       STM32_MCO1PRE_DIV1
 #define STM32_MCO2SEL                       STM32_MCO2SEL_SYSCLK
 #define STM32_MCO2PRE                       STM32_MCO2PRE_DIV5
-#define STM32_I2SSRC                        STM32_I2SSRC_CKIN
+#define STM32_I2SSRC                        STM32_I2SSRC_PLLI2S
 #define STM32_PLLI2SN_VALUE                 192
 #define STM32_PLLI2SR_VALUE                 5
 #define STM32_PVD_ENABLE                    FALSE