Merge branch 'bugfix/lp_uart_rx_iomux_pin_not_work_v5.4' into 'release/v5.4'

fix(uart): lp uart rx iomux pin was not working as expected (v5.4)

See merge request espressif/esp-idf!47609

components/esp_driver_gpio/include/driver/rtc_io.h

@@ -210,6 +210,31 @@ esp_err_t rtc_gpio_get_drive_capability(gpio_num_t gpio_num, gpio_drive_cap_t* s
  */
 esp_err_t rtc_gpio_iomux_func_sel(gpio_num_t gpio_num, int func);
 
+/**
+  * @brief Set pad input to an LP peripheral signal through the LP(RTC) IOMUX.
+  *
+  * @param gpio_num GPIO number
+  * @param func The index number of the LP(RTC) IOMUX function to be selected for the pin
+  * @param signal_idx Peripheral signal index to input. One of the ``*_IN_IDX`` signals in ``soc/lp_gpio_sig_map.h``.
+  *
+  * @return
+  *     - ESP_OK Success
+  *     - ESP_ERR_INVALID_ARG GPIO number error
+  */
+esp_err_t rtc_gpio_iomux_input(gpio_num_t gpio_num, int func, uint32_t signal_idx);
+
+/**
+  * @brief Set LP peripheral output to an RTC IO pad through the LP(RTC) IOMUX.
+  *
+  * @param gpio_num GPIO number
+  * @param func The index number of the LP(RTC) IOMUX function to be selected for the pin
+  *
+  * @return
+  *     - ESP_OK Success
+  *     - ESP_ERR_INVALID_ARG GPIO number error
+  */
+esp_err_t rtc_gpio_iomux_output(gpio_num_t gpio_num, int func);
+
 #endif // SOC_RTCIO_INPUT_OUTPUT_SUPPORTED
 
 #if SOC_RTCIO_HOLD_SUPPORTED

components/esp_driver_gpio/src/rtc_io.c

@@ -183,6 +183,24 @@ esp_err_t rtc_gpio_iomux_func_sel(gpio_num_t gpio_num, int func)
     return ESP_OK;
 }
 
+esp_err_t rtc_gpio_iomux_input(gpio_num_t gpio_num, int func, uint32_t signal_idx)
+{
+    ESP_RETURN_ON_FALSE(rtc_gpio_is_valid_gpio(gpio_num), ESP_ERR_INVALID_ARG, RTCIO_TAG, "RTCIO number error");
+    RTCIO_ENTER_CRITICAL();
+    rtcio_hal_iomux_input(rtc_io_number_get(gpio_num), func, signal_idx);
+    RTCIO_EXIT_CRITICAL();
+    return ESP_OK;
+}
+
+esp_err_t rtc_gpio_iomux_output(gpio_num_t gpio_num, int func)
+{
+    ESP_RETURN_ON_FALSE(rtc_gpio_is_valid_gpio(gpio_num), ESP_ERR_INVALID_ARG, RTCIO_TAG, "RTCIO number error");
+    RTCIO_ENTER_CRITICAL();
+    rtcio_hal_iomux_output(rtc_io_number_get(gpio_num), func);
+    RTCIO_EXIT_CRITICAL();
+    return ESP_OK;
+}
+
 #if SOC_LP_GPIO_MATRIX_SUPPORTED
 esp_err_t lp_gpio_connect_in_signal(gpio_num_t gpio_num, uint32_t signal_idx, bool inv)
 {

components/esp_driver_uart/src/uart.c

@@ -724,13 +724,12 @@ static bool uart_try_set_iomux_pin(uart_port_t uart_num, int io_num, uint32_t id
     }
 #if (SOC_UART_LP_NUM >= 1) && (SOC_RTCIO_PIN_COUNT >= 1)
     else {
-        if (upin->input) {
-            rtc_gpio_set_direction(io_num, RTC_GPIO_MODE_INPUT_ONLY);
-        } else {
-            rtc_gpio_set_direction(io_num, RTC_GPIO_MODE_OUTPUT_ONLY);
-        }
         rtc_gpio_init(io_num);
-        rtc_gpio_iomux_func_sel(io_num, upin->iomux_func);
+        if (upin->input) {
+            rtc_gpio_iomux_input(io_num, upin->iomux_func, upin->signal);
+        } else {
+            rtc_gpio_iomux_output(io_num, upin->iomux_func);
+        }
         // undo the workaround done in uart_module_enable for RX pin
 #if !SOC_LP_GPIO_MATRIX_SUPPORTED
         if (upin->input) {

components/hal/esp32p4/include/hal/rtc_io_ll.h

@@ -85,11 +85,37 @@ static inline void rtcio_ll_matrix_out(int rtcio_num, uint32_t signal_idx, bool
     reg.func_out_sel = signal_idx;
     reg.out_inv_sel = out_inv;
     reg.oe_inv_sel = oen_inv;
+    reg.oe_sel = 0; // output enable signal controlled by peripheral
     LP_GPIO.func_out_sel_cfg[rtcio_num].val = reg.val;
 
     HAL_FORCE_MODIFY_U32_REG_FIELD(LP_GPIO.enable_w1ts, reg_gpio_enable_data_w1ts, BIT(rtcio_num));
 }
 
+/**
+  * @brief Configure peripheral signal input whether to bypass LP_GPIO matrix.
+  *
+  * @param signal_idx LP peripheral signal index.
+  * @param from_gpio_matrix True if not to bypass LP_GPIO matrix, otherwise False.
+  */
+static inline void rtcio_ll_set_input_signal_from(uint32_t signal_idx, bool from_gpio_matrix)
+{
+    LP_GPIO.func_in_sel_cfg[signal_idx].sig_in_sel = from_gpio_matrix;
+}
+
+/**
+  * @brief Configure the source of output enable signal for the pad (only takes effect if func sel is selected to be LP_GPIO).
+  *
+  * @param rtcio_num The index of rtcio. 0 ~ MAX(rtcio).
+  * @param ctrl_by_periph True if use output enable signal from peripheral, false if force the output enable signal to be sourced from bit n of LP_GPIO_ENABLE_REG
+  * @param oen_inv True if the output enable needs to be inverted, otherwise False.
+  */
+__attribute__((always_inline))
+static inline void rtcio_ll_set_output_enable_ctrl(int rtcio_num, bool ctrl_by_periph, bool oen_inv)
+{
+    LP_GPIO.func_out_sel_cfg[rtcio_num].oe_inv_sel = oen_inv;       // control valid only when using lp gpio matrix to route signal to the LP IO
+    LP_GPIO.func_out_sel_cfg[rtcio_num].oe_sel = !ctrl_by_periph;
+}
+
 /**
  * @brief Select a RTC IOMUX function for the RTC IO
  *

components/hal/include/hal/rtc_io_hal.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
  */
@@ -199,6 +199,23 @@ void rtcio_hal_set_direction_in_sleep(int rtcio_num, rtc_gpio_mode_t mode);
  */
 #define rtcio_hal_iomux_func_sel(rtcio_num, func) rtcio_ll_iomux_func_sel(rtcio_num, func)
 
+/**
+  * @brief Set pad input to an LP peripheral signal through the LP(RTC) IOMUX
+  *
+  * @param rtcio_num The index of rtcio. 0 ~ SOC_RTCIO_PIN_COUNT.
+  * @param func The index number of the IOMUX function to be selected for the pin.
+  * @param signal_idx Peripheral signal index to input. One of the ``*_IN_IDX`` signals in ``soc/lp_gpio_sig_map.h``.
+  */
+void rtcio_hal_iomux_input(int rtcio_num, int func, uint32_t signal_idx);
+
+/**
+  * @brief Set LP peripheral output to an RTC IO pad through the LP(RTC) IOMUX
+  *
+  * @param rtcio_num The index of rtcio. 0 ~ SOC_RTCIO_PIN_COUNT.
+  * @param func The index number of the LP(RTC) IOMUX function to be selected for the pin
+  */
+void rtcio_hal_iomux_output(int rtcio_num, int func);
+
 #if SOC_LP_GPIO_MATRIX_SUPPORTED
 /**
  * Select RTC GPIO input to a signal

components/hal/rtc_io_hal.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2015-2023 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2015-2026 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -88,4 +88,19 @@ void rtcio_hal_isolate(int rtcio_num)
 }
 #endif
 
+void rtcio_hal_iomux_input(int rtcio_num, int func, uint32_t signal_idx)
+{
+    rtcio_ll_input_enable(rtcio_num);
+    rtcio_ll_iomux_func_sel(rtcio_num, func);
+#if SOC_LP_GPIO_MATRIX_SUPPORTED
+    rtcio_ll_set_input_signal_from(signal_idx, false);
+#endif
+}
+
+void rtcio_hal_iomux_output(int rtcio_num, int func)
+{
+    rtcio_ll_iomux_func_sel(rtcio_num, func);
+    // as long as the func sel is not RTC IO, the oe can only be controlled by the peripheral
+}
+
 #endif //SOC_RTCIO_INPUT_OUTPUT_SUPPORTED