From 61f19094b029057c8ae961f434f45ff84eed9065 Mon Sep 17 00:00:00 2001
From: wangyuanze <wangyuanze@espressif.com>
Date: Thu, 14 Jul 2022 10:08:29 +0800
Subject: [PATCH] example: fix rmt callback memory issue in ir_nec_transceiver

---
 components/driver/include/driver/rmt_types.h     |  7 ++++---
 .../main/ir_nec_transceiver_main.c               | 16 +++++++++-------
 2 files changed, 13 insertions(+), 10 deletions(-)

diff --git a/components/driver/include/driver/rmt_types.h b/components/driver/include/driver/rmt_types.h
index dd05b4cae0..96d1f5d936 100644
--- a/components/driver/include/driver/rmt_types.h
+++ b/components/driver/include/driver/rmt_types.h
@@ -40,7 +40,8 @@ typedef struct {
 /**
  * @brief Prototype of RMT event callback
  * @param[in] tx_chan RMT channel handle, created from `rmt_new_tx_channel()`
- * @param[in] edata RMT event data
+ * @param[in] edata Point to RMT event data. The lifecycle of this pointer memory is inside this function,
+ *                  user should copy it into static memory if used outside this funcion.
  * @param[in] user_ctx User registered context, passed from `rmt_tx_register_event_callbacks()`
  *
  * @return Whether a high priority task has been waken up by this callback function
@@ -59,9 +60,9 @@ typedef struct {
  * @brief Prototype of RMT event callback
  *
  * @param[in] rx_chan RMT channel handle, created from `rmt_new_rx_channel()`
- * @param[in] edata Point to RMT event data
+ * @param[in] edata Point to RMT event data. The lifecycle of this pointer memory is inside this function,
+ *                  user should copy it into static memory if used outside this funcion.
  * @param[in] user_ctx User registered context, passed from `rmt_rx_register_event_callbacks()`
- *
  * @return Whether a high priority task has been waken up by this function
  */
 typedef bool (*rmt_rx_done_callback_t)(rmt_channel_handle_t rx_chan, rmt_rx_done_event_data_t *edata, void *user_ctx);
diff --git a/examples/peripherals/rmt/ir_nec_transceiver/main/ir_nec_transceiver_main.c b/examples/peripherals/rmt/ir_nec_transceiver/main/ir_nec_transceiver_main.c
index c07a054b38..b376105d07 100644
--- a/examples/peripherals/rmt/ir_nec_transceiver/main/ir_nec_transceiver_main.c
+++ b/examples/peripherals/rmt/ir_nec_transceiver/main/ir_nec_transceiver_main.c
@@ -6,6 +6,7 @@
 
 #include "freertos/FreeRTOS.h"
 #include "freertos/task.h"
+#include "freertos/queue.h"
 #include "esp_log.h"
 #include "driver/rmt_tx.h"
 #include "driver/rmt_rx.h"
@@ -144,9 +145,9 @@ static void example_parse_nec_frame(rmt_symbol_word_t *rmt_nec_symbols, size_t s
 static bool example_rmt_rx_done_callback(rmt_channel_handle_t channel, rmt_rx_done_event_data_t *edata, void *user_data)
 {
     BaseType_t high_task_wakeup = pdFALSE;
-    TaskHandle_t task_to_notify = (TaskHandle_t)user_data;
+    QueueHandle_t receive_queue = (QueueHandle_t)user_data;
     // send the received RMT symbols to the parser task
-    xTaskNotifyFromISR(task_to_notify, (uint32_t)edata, eSetValueWithOverwrite, &high_task_wakeup);
+    xQueueSendFromISR(receive_queue, edata, &high_task_wakeup);
     return high_task_wakeup == pdTRUE;
 }
 
@@ -163,11 +164,12 @@ void app_main(void)
     ESP_ERROR_CHECK(rmt_new_rx_channel(&rx_channel_cfg, &rx_channel));
 
     ESP_LOGI(TAG, "register RX done callback");
-    TaskHandle_t cur_task = xTaskGetCurrentTaskHandle();
+    QueueHandle_t receive_queue = xQueueCreate(1, sizeof(rmt_rx_done_event_data_t));
+    assert(receive_queue);
     rmt_rx_event_callbacks_t cbs = {
         .on_recv_done = example_rmt_rx_done_callback,
     };
-    ESP_ERROR_CHECK(rmt_rx_register_event_callbacks(rx_channel, &cbs, cur_task));
+    ESP_ERROR_CHECK(rmt_rx_register_event_callbacks(rx_channel, &cbs, receive_queue));
 
     // the following timing requirement is based on NEC protocol
     rmt_receive_config_t receive_config = {
@@ -211,14 +213,14 @@ void app_main(void)
 
     // save the received RMT symbols
     rmt_symbol_word_t raw_symbols[64]; // 64 symbols should be sufficient for a standard NEC frame
-    rmt_rx_done_event_data_t *rx_data = NULL;
+    rmt_rx_done_event_data_t rx_data;
     // ready to receive
     ESP_ERROR_CHECK(rmt_receive(rx_channel, raw_symbols, sizeof(raw_symbols), &receive_config));
     while (1) {
         // wait for RX done signal
-        if (xTaskNotifyWait(0x00, ULONG_MAX, (uint32_t *)&rx_data, pdMS_TO_TICKS(1000)) == pdTRUE) {
+        if (xQueueReceive(receive_queue, &rx_data, pdMS_TO_TICKS(1000)) == pdPASS) {
             // parse the receive symbols and print the result
-            example_parse_nec_frame(rx_data->received_symbols, rx_data->num_symbols);
+            example_parse_nec_frame(rx_data.received_symbols, rx_data.num_symbols);
             // start receive again
             ESP_ERROR_CHECK(rmt_receive(rx_channel, raw_symbols, sizeof(raw_symbols), &receive_config));
         } else {