fixup! cpu/esp32: uart API function uart_mode added

Author: gschorcht

cpu/esp32/periph/uart.c

@@ -395,13 +395,29 @@ static int _uart_set_mode(uart_t uart, uart_data_bits_t data_bits,
     _uarts[uart].data = data_bits;
 
     /* set number of stop bits */
+    #ifdef MCU_ESP32
+    /* workaround for hardware bug when stop bits are set to 2-bit mode. */
+    switch (stop_bits) {
+        case UART_STOP_BITS_1: _uarts[uart].regs->conf0.stop_bit_num = 1;
+                               _uarts[uart].regs->rs485_conf.dl1_en = 1;
+                               break;
+        case UART_STOP_BITS_2: _uarts[uart].regs->conf0.stop_bit_num = 1;
+                               _uarts[uart].regs->rs485_conf.dl1_en = 1;
+                               break;
+        default: LOG_TAG_ERROR("uart", "invalid number of stop bits\n");
+                 critical_exit();
+                 return UART_NOMODE;
+    }
+    #else
     switch (stop_bits) {
         case UART_STOP_BITS_1: _uarts[uart].regs->conf0.stop_bit_num = 1; break;
         case UART_STOP_BITS_2: _uarts[uart].regs->conf0.stop_bit_num = 3; break;
         default: LOG_TAG_ERROR("uart", "invalid number of stop bits\n");
                  critical_exit();
                  return UART_NOMODE;
     }
+    #endif
+
     /* store changed number of stop bits in configuration */
     _uarts[uart].stop = stop_bits;