From 1066c74b744e4b418168d3bb717adb73ca346171 Mon Sep 17 00:00:00 2001
From: Krzysztof Bociurko <git@chanibal.pl>
Date: Fri, 27 Oct 2017 15:23:07 +0200
Subject: [PATCH] rmt: Adds a simple handler that can be called when
 transmission ends.

Merges https://github.com/espressif/esp-idf/pull/1174
---
 components/driver/include/driver/rmt.h | 16 ++++++++++++++++
 components/driver/rmt.c                | 12 ++++++++++++
 2 files changed, 28 insertions(+)

diff --git a/components/driver/include/driver/rmt.h b/components/driver/include/driver/rmt.h
index 79ac0e5d6..009041bfd 100644
--- a/components/driver/include/driver/rmt.h
+++ b/components/driver/include/driver/rmt.h
@@ -119,6 +119,8 @@ typedef struct {
 
 typedef intr_handle_t rmt_isr_handle_t;
 
+typedef void (*rmt_tx_end_t)(rmt_channel_t channel);
+
 /**
  * @brief Set RMT clock divider, channel clock is divided from source clock.
  *
@@ -702,6 +704,20 @@ esp_err_t rmt_wait_tx_done(rmt_channel_t channel, TickType_t wait_time);
  */
 esp_err_t rmt_get_ringbuf_handle(rmt_channel_t channel, RingbufHandle_t* buf_handle);
 
+/**
+ * @brief Registers a callback that will be called when transmission ends.
+ *
+ *        Called by rmt_driver_isr_default in interrupt context.
+ *
+ * @note Requires rmt_driver_install to install the default ISR handler.
+ *
+ * @param fn Function to be called from the default interrupt handler or NULL.
+ *
+ * @return the previous handler (or NULL if there was none)
+ */
+rmt_tx_end_t rmt_register_tx_end_callback(rmt_tx_end_t fn);
+
+
 /*
  * ----------------EXAMPLE OF RMT INTERRUPT ------------------
  * @code{c}
diff --git a/components/driver/rmt.c b/components/driver/rmt.c
index 09cf94c14..eb102fc7b 100644
--- a/components/driver/rmt.c
+++ b/components/driver/rmt.c
@@ -75,6 +75,9 @@ typedef struct {
 
 rmt_obj_t* p_rmt_obj[RMT_CHANNEL_MAX] = {0};
 
+// Event called when transmission is ended
+static rmt_tx_end_t rmt_tx_end_callback = NULL;
+
 static void rmt_set_tx_wrap_en(rmt_channel_t channel, bool en)
 {
     portENTER_CRITICAL(&rmt_spinlock);
@@ -548,6 +551,9 @@ static void IRAM_ATTR rmt_driver_isr_default(void* arg)
                         p_rmt->tx_len_rem = 0;
                         p_rmt->tx_offset = 0;
                         p_rmt->tx_sub_len = 0;
+                        if(rmt_tx_end_callback != NULL) {
+                            rmt_tx_end_callback(channel);
+                        }
                         break;
                         //RX_END
                     case 1:
@@ -771,3 +777,9 @@ esp_err_t rmt_get_ringbuf_handle(rmt_channel_t channel, RingbufHandle_t* buf_han
     return ESP_OK;
 }
 
+rmt_tx_end_t rmt_register_tx_end_callback(rmt_tx_end_t handler)
+{
+    rmt_tx_end_t previous = rmt_tx_end_callback;
+    rmt_tx_end_callback = handler;
+    return previous;
+}