From f773c59e89cc9bdc78c0450e7b1b878704df4631 Mon Sep 17 00:00:00 2001 From: Song Ruo Jing Date: Wed, 11 Feb 2026 21:07:16 +0800 Subject: [PATCH 1/2] fix(uart): tx write bytes fails to use non-default tx fifo empty threshold Users may see tx write bytes fails to feed data into tx fifo in time even if the tx fifo empty threshold has been set to a large value. --- components/esp_driver_uart/include/driver/uart.h | 10 +++++----- components/esp_driver_uart/src/uart.c | 9 ++++++--- 2 files changed, 11 insertions(+), 8 deletions(-) diff --git a/components/esp_driver_uart/include/driver/uart.h b/components/esp_driver_uart/include/driver/uart.h index e09dee4ce30..13aa41cfacb 100644 --- a/components/esp_driver_uart/include/driver/uart.h +++ b/components/esp_driver_uart/include/driver/uart.h @@ -1,5 +1,5 @@ /* - * SPDX-FileCopyrightText: 2015-2025 Espressif Systems (Shanghai) CO LTD + * SPDX-FileCopyrightText: 2015-2026 Espressif Systems (Shanghai) CO LTD * * SPDX-License-Identifier: Apache-2.0 */ @@ -365,7 +365,7 @@ esp_err_t uart_enable_rx_intr(uart_port_t uart_num); esp_err_t uart_disable_rx_intr(uart_port_t uart_num); /** - * @brief Disable UART TX interrupt (TX_FULL & TX_TIMEOUT INTERRUPT) + * @brief Disable UART TX interrupt (TX_FIFO_EMPTY INTERRUPT) * * @param uart_num UART port number * @@ -376,11 +376,11 @@ esp_err_t uart_disable_rx_intr(uart_port_t uart_num); esp_err_t uart_disable_tx_intr(uart_port_t uart_num); /** - * @brief Enable UART TX interrupt (TX_FULL & TX_TIMEOUT INTERRUPT) + * @brief Enable UART TX interrupt (TX_FIFO_EMPTY INTERRUPT) * * @param uart_num UART port number, the max port number is (UART_NUM_MAX -1). - * @param enable 1: enable; 0: disable - * @param thresh Threshold of TX interrupt, 0 ~ UART_HW_FIFO_LEN(uart_num) + * @param enable Set to 1 to enable the interrupt + * @param thresh Threshold of TX FIFO empty interrupt, 0 ~ UART_HW_FIFO_LEN(uart_num). If -1 is given, threshold configuration will be skipped. * * @return * - ESP_OK Success diff --git a/components/esp_driver_uart/src/uart.c b/components/esp_driver_uart/src/uart.c index 6f979b40834..e300a431d5c 100644 --- a/components/esp_driver_uart/src/uart.c +++ b/components/esp_driver_uart/src/uart.c @@ -680,11 +680,14 @@ esp_err_t uart_disable_tx_intr(uart_port_t uart_num) esp_err_t uart_enable_tx_intr(uart_port_t uart_num, int enable, int thresh) { + (void)enable; ESP_RETURN_ON_FALSE((uart_num < UART_NUM_MAX), ESP_FAIL, UART_TAG, "uart_num error"); ESP_RETURN_ON_FALSE((thresh < UART_HW_FIFO_LEN(uart_num)), ESP_FAIL, UART_TAG, "empty intr threshold error"); uart_hal_clr_intsts_mask(&(uart_context[uart_num].hal), UART_INTR_TXFIFO_EMPTY); UART_ENTER_CRITICAL(&(uart_context[uart_num].spinlock)); - uart_hal_set_txfifo_empty_thr(&(uart_context[uart_num].hal), thresh); + if (thresh != -1) { + uart_hal_set_txfifo_empty_thr(&(uart_context[uart_num].hal), thresh); + } uart_hal_ena_intr_mask(&(uart_context[uart_num].hal), UART_INTR_TXFIFO_EMPTY); UART_EXIT_CRITICAL(&(uart_context[uart_num].spinlock)); return ESP_OK; @@ -1545,7 +1548,7 @@ static int uart_tx_all(uart_port_t uart_num, const char *src, size_t size, bool xRingbufferSend(p_uart_obj[uart_num]->tx_ring_buf, (void *)(src + offset), send_size, portMAX_DELAY); size -= send_size; offset += send_size; - uart_enable_tx_intr(uart_num, 1, UART_THRESHOLD_NUM(uart_num, UART_EMPTY_THRESH_DEFAULT)); + uart_enable_tx_intr(uart_num, 1, -1); } } } else { @@ -1555,7 +1558,7 @@ static int uart_tx_all(uart_port_t uart_num, const char *src, size_t size, bool uint32_t sent = uart_enable_tx_write_fifo(uart_num, (const uint8_t *) src, size); if (sent < size) { p_uart_obj[uart_num]->tx_waiting_fifo = true; - uart_enable_tx_intr(uart_num, 1, UART_THRESHOLD_NUM(uart_num, UART_EMPTY_THRESH_DEFAULT)); + uart_enable_tx_intr(uart_num, 1, -1); } size -= sent; src += sent; From be2bb37f0e7d727797642c4468faadb26cf68145 Mon Sep 17 00:00:00 2001 From: Song Ruo Jing Date: Fri, 28 Nov 2025 20:34:06 +0800 Subject: [PATCH 2/2] fix(uart): Avoid division by zero error when calling uart_get_baudrate If uart_driver_install is not called before uart_get_baudrate, the UART port may not be ready. In such cases, the register values cannot be read out, leading to a division by zero error in uart_ll_get_baudrate. This commit adds a check to ensure the UART port is enabled before attempting to read its registers. Closes https://github.com/espressif/esp-idf/issues/17513 --- components/esp_driver_uart/include/driver/uart.h | 2 +- components/esp_driver_uart/src/uart.c | 1 + 2 files changed, 2 insertions(+), 1 deletion(-) diff --git a/components/esp_driver_uart/include/driver/uart.h b/components/esp_driver_uart/include/driver/uart.h index 13aa41cfacb..911e138c947 100644 --- a/components/esp_driver_uart/include/driver/uart.h +++ b/components/esp_driver_uart/include/driver/uart.h @@ -248,7 +248,7 @@ esp_err_t uart_set_baudrate(uart_port_t uart_num, uint32_t baudrate); * @param baudrate Pointer to accept value of UART baud rate * * @return - * - ESP_FAIL Parameter error + * - ESP_FAIL Parameter error or the UART port is not enabled * - ESP_OK Success, result will be put in (*baudrate) * */ diff --git a/components/esp_driver_uart/src/uart.c b/components/esp_driver_uart/src/uart.c index e300a431d5c..70a5da83eee 100644 --- a/components/esp_driver_uart/src/uart.c +++ b/components/esp_driver_uart/src/uart.c @@ -390,6 +390,7 @@ esp_err_t uart_set_baudrate(uart_port_t uart_num, uint32_t baud_rate) esp_err_t uart_get_baudrate(uart_port_t uart_num, uint32_t *baudrate) { ESP_RETURN_ON_FALSE((uart_num < UART_NUM_MAX), ESP_FAIL, UART_TAG, "uart_num error"); + ESP_RETURN_ON_FALSE(uart_ll_is_enabled(uart_num), ESP_FAIL, UART_TAG, "uart port not enabled, unable to get register values"); soc_module_clk_t src_clk; uint32_t sclk_freq;