diff --git a/components/esp_driver_uart/include/driver/uart.h b/components/esp_driver_uart/include/driver/uart.h
index d0a4e59c761b..fa7f18286a62 100644
--- a/components/esp_driver_uart/include/driver/uart.h
+++ b/components/esp_driver_uart/include/driver/uart.h
@@ -68,6 +68,8 @@ typedef struct {
  */
 typedef enum {
     UART_DATA,              /*!< UART data event*/
+    UART_TX_DONE,           /*!< UART TX done*/  // Toit extension.
+    UART_TX_ENTRY_RETIRED,  /*!< UART TX entry retired*/  // Toit extension.
     UART_BREAK,             /*!< UART break event*/
     UART_BUFFER_FULL,       /*!< UART RX buffer full event*/
     UART_FIFO_OVF,          /*!< UART FIFO overflow event*/
diff --git a/components/esp_driver_uart/src/uart.c b/components/esp_driver_uart/src/uart.c
index fdfa21db2227..e9220510aaea 100644
--- a/components/esp_driver_uart/src/uart.c
+++ b/components/esp_driver_uart/src/uart.c
@@ -84,6 +84,7 @@ static const char *UART_TAG = "uart";
                             | (UART_INTR_RXFIFO_TOUT) \
                             | (UART_INTR_RXFIFO_OVF) \
                             | (UART_INTR_BRK_DET) \
+                            | (UART_INTR_TX_DONE) /* Toit extension. */ \
                             | (UART_INTR_PARITY_ERR)) \
                             | (UART_INTR_WAKEUP)
 #else
@@ -91,6 +92,7 @@ static const char *UART_TAG = "uart";
                             | (UART_INTR_RXFIFO_TOUT) \
                             | (UART_INTR_RXFIFO_OVF) \
                             | (UART_INTR_BRK_DET) \
+                            | (UART_INTR_TX_DONE) /* Toit extension. */ \
                             | (UART_INTR_PARITY_ERR))
 #endif
 
@@ -1040,6 +1042,8 @@ static void UART_ISR_ATTR uart_rx_intr_handler_default(void *param)
                 if (p_uart->tx_buf_size == 0) {
                     continue;
                 }
+                // Toit extension.
+                bool retired = false;
                 bool en_tx_flg = false;
                 uint32_t tx_fifo_rem = uart_hal_get_txfifo_len(&(uart_context[uart_num].hal));
                 //We need to put a loop here, in case all the buffer items are very short.
@@ -1087,6 +1091,7 @@ static void UART_ISR_ATTR uart_rx_intr_handler_default(void *param)
                             need_yield |= (HPTaskAwoken == pdTRUE);
                             p_uart->tx_head = NULL;
                             p_uart->tx_ptr = NULL;
+                            retired = true;  // Toit extension.
                             //Sending item done, now we need to send break if there is a record.
                             //Set TX break signal after FIFO is empty
                             if (p_uart->trans_total_remaining_len == 0 && p_uart->tx_brk_flg == 1) {
@@ -1114,6 +1119,12 @@ static void UART_ISR_ATTR uart_rx_intr_handler_default(void *param)
                         }
                     }
                 }
+                {
+                    // Toit extension.
+                    if (retired) {
+                        uart_event.type = UART_TX_ENTRY_RETIRED;
+                    }
+                }
                 if (en_tx_flg) {
                     uart_hal_clr_intsts_mask(&(uart_context[uart_num].hal), UART_INTR_TXFIFO_EMPTY);
                     UART_ENTER_CRITICAL_ISR(&(uart_context[uart_num].spinlock));
@@ -1197,6 +1208,13 @@ static void UART_ISR_ATTR uart_rx_intr_handler_default(void *param)
                             uart_pattern_enqueue(uart_num, p_uart->rx_buffered_len + pat_idx);
                         }
                     }
+                    {
+                        // Toit extension:
+                        // No need to send a data event if there is already data queued.
+                        if (uart_event.type == UART_DATA && p_uart->rx_buffered_len > 0) {
+                            uart_event.type = UART_EVENT_MAX; // invalidate event
+                        }
+                    }
                     p_uart->rx_buffered_len += p_uart->rx_stash_len;
                     UART_EXIT_CRITICAL_ISR(&(uart_context[uart_num].spinlock));
                 }
@@ -1310,6 +1328,17 @@ static void UART_ISR_ATTR uart_rx_intr_handler_default(void *param)
                 xSemaphoreGiveFromISR(p_uart_obj[uart_num]->tx_done_sem, &HPTaskAwoken);
                 need_yield |= (HPTaskAwoken == pdTRUE);
             }
+            {
+                // Toit extension.
+                // Inform the runtime that everything has been transmitted.
+                if (p_uart->trans_total_remaining_len == 0) {
+                    UBaseType_t items_waiting;
+                    vRingbufferGetInfo(p_uart->tx_ring_buf, NULL, NULL, NULL, NULL, &items_waiting);
+                    if (items_waiting == 0) {
+                        uart_event.type = UART_TX_DONE;
+                    }
+                }
+            }
         }
 #if SOC_UART_SUPPORT_WAKEUP_INT
         else if (uart_intr_status & UART_INTR_WAKEUP) {