Merged in juniskane/nuttx_stm32l4/stm32l4_serial_pr (pull request #365)

STM32L4: port stm32l4_serial_get_uart function from STM32F7

Approved-by: Gregory Nutt <gnutt@nuttx.org>

arch/arm/src/stm32l4/stm32l4_serial.c

@@ -200,6 +200,10 @@ struct stm32l4_serial_s
   uint16_t          ie;        /* Saved interrupt mask bits value */
   uint16_t          sr;        /* Saved status bits */
 
+  /* Has been initialized and HW is setup. */
+
+  bool              initialized;
+
   /* If termios are supported, then the following fields may vary at
    * runtime.
    */
@@ -1169,6 +1173,11 @@ static int stm32l4serial_setup(FAR struct uart_dev_s *dev)
   /* Set up the cached interrupt enables value */
 
   priv->ie    = 0;
+
+  /* Mark device as initialized. */
+
+  priv->initialized = true;
+
   return OK;
 }
 
@@ -1279,6 +1288,10 @@ static void stm32l4serial_shutdown(FAR struct uart_dev_s *dev)
   FAR struct stm32l4_serial_s *priv = (FAR struct stm32l4_serial_s *)dev->priv;
   uint32_t regval;
 
+  /* Mark device as uninitialized. */
+
+  priv->initialized = false;
+
   /* Disable all interrupts */
 
   stm32l4serial_disableusartint(priv, NULL);
@@ -2327,6 +2340,32 @@ static int stm32l4serial_pmprepare(FAR struct pm_callback_s *cb, int domain,
 
 #ifdef USE_SERIALDRIVER
 
+/****************************************************************************
+ * Name: stm32l4_serial_get_uart
+ *
+ * Description:
+ *   Get serial driver structure for STM32 USART
+ *
+ ****************************************************************************/
+
+FAR uart_dev_t *stm32l4_serial_get_uart(int uart_num)
+{
+  int uart_idx = uart_num - 1;
+
+  if (uart_idx < 0 || uart_idx >= STM32L4_NUSART+STM32L4_NUART || \
+      !uart_devs[uart_idx])
+    {
+      return NULL;
+    }
+
+  if (!uart_devs[uart_idx]->initialized)
+    {
+      return NULL;
+    }
+
+  return &uart_devs[uart_idx]->dev;
+}
+
 /****************************************************************************
  * Name: up_earlyserialinit
  *
@@ -2360,10 +2399,10 @@ void up_earlyserialinit(void)
 #endif
 #endif /* HAVE UART */
 }
-#endif
+#endif /* USE_EARLYSERIALINIT */
 
 /****************************************************************************
- * Name: stm32l4serial_getregit
+ * Name: up_serialinit
  *
  * Description:
  *   Register serial console and serial ports.  This assumes
@@ -2441,7 +2480,7 @@ void up_serialinit(void)
 }
 
 /****************************************************************************
- * Name: stm32l4serial_dmapoll
+ * Name: stm32l4_serial_dma_poll
  *
  * Description:
  *   Checks receive DMA buffers for received bytes that have not accumulated
@@ -2452,7 +2491,7 @@ void up_serialinit(void)
  ****************************************************************************/
 
 #ifdef SERIAL_HAVE_DMA
-void stm32l4serial_dmapoll(void)
+void stm32l4_serial_dma_poll(void)
 {
     irqstate_t flags;
 

arch/arm/src/stm32l4/stm32l4_uart.h

@@ -41,6 +41,7 @@
  ************************************************************************************/
 
 #include <nuttx/config.h>
+#include <nuttx/serial/serial.h>
 
 #include "chip.h"
 
@@ -236,6 +237,16 @@ extern "C"
  * Public Functions
  ************************************************************************************/
 
+/************************************************************************************
+ * Name: stm32l4_serial_get_uart
+ *
+ * Description:
+ *   Get serial driver structure for STM32 USART
+ *
+ ************************************************************************************/
+
+FAR uart_dev_t *stm32l4_serial_get_uart(int uart_num);
+
 /************************************************************************************
  * Name: stm32l4_serial_dma_poll
  *