cpu/esp_common/freertos: add required ringbuffer handling

cpu/esp_common/freertos/ringbuf.c

@@ -0,0 +1,104 @@
+/*
+ * Copyright (C) 2022 Gunar Schorcht
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ *
+ * FreeRTOS to RIOT-OS adaption module for source code compatibility
+ */
+
+#include <assert.h>
+#include <stdlib.h>
+
+#include "irq_arch.h"
+#include "ringbuffer.h"
+
+#include "freertos/FreeRTOS.h"
+#include "freertos/ringbuf.h"
+
+#define ENABLE_DEBUG 0
+#include "debug.h"
+
+typedef struct {
+    ringbuffer_t rbuf;
+    uint16_t item_size;
+    char *buf;
+} rbuf_handle_t;
+
+RingbufHandle_t xRingbufferCreate(size_t xBufferSize, RingbufferType_t xBufferType)
+{
+    /* only byte buffer supported for now */
+    assert(xBufferType == RINGBUF_TYPE_BYTEBUF);
+
+    /* allocate the space for rbuf_handle_t including the buffer */
+    rbuf_handle_t *handle = malloc(xBufferSize + sizeof(uint16_t) + sizeof(ringbuffer_t));
+    if (handle == NULL) {
+        return NULL;
+    }
+    handle->item_size = 0;
+    ringbuffer_init((ringbuffer_t *)handle, handle->buf, xBufferSize);
+
+    return handle;
+}
+
+void vRingbufferDelete(RingbufHandle_t xRingbuffer)
+{
+    assert(xRingbuffer != NULL);
+    free(xRingbuffer);
+}
+
+void *xRingbufferReceiveUpToFromISR(RingbufHandle_t xRingbuffer,
+                                    size_t *pxItemSize, size_t xMaxSize)
+{
+    rbuf_handle_t *handle = xRingbuffer;
+    size_t data_len = 0;
+
+    assert(handle != NULL);
+
+    /* determine the number of bytes to be read */
+    if (handle->rbuf.avail) {
+        data_len = ((xMaxSize == 0) || (handle->rbuf.avail < xMaxSize)) ? handle->rbuf.avail
+                                                                        : xMaxSize;
+    }
+    /* ESP-IDF ring buffers require two read operation if the data wrap around */
+    if (data_len > (handle->rbuf.size - handle->rbuf.start)) {
+        data_len = handle->rbuf.size - handle->rbuf.start;
+    }
+    handle->item_size = data_len;
+    *pxItemSize = data_len;
+
+    return handle->rbuf.buf + handle->rbuf.start;
+}
+
+void *xRingbufferReceiveFromISR(RingbufHandle_t xRingbuffer, size_t *pxItemSize)
+{
+    return xRingbufferReceiveUpToFromISR(xRingbuffer, pxItemSize, 0);
+}
+
+void vRingbufferReturnItemFromISR(RingbufHandle_t xRingbuffer, void *pvItem,
+                                  BaseType_t *pxHigherPriorityTaskWoken)
+{
+    rbuf_handle_t *handle = xRingbuffer;
+    if (handle->item_size) {
+        ringbuffer_remove(&handle->rbuf, handle->item_size);
+    }
+}
+
+BaseType_t xRingbufferSendFromISR(RingbufHandle_t xRingbuffer,
+                                  const void *pvItem,
+                                  size_t xItemSize,
+                                  BaseType_t *pxHigherPriorityTaskWoken)
+{
+    rbuf_handle_t *handle = xRingbuffer;
+
+    assert(handle != NULL);
+
+    /* return immediately if there is not enough space in the ring buffer */
+    if (ringbuffer_get_free(&handle->rbuf) < xItemSize) {
+        return pdFALSE;
+    }
+
+    /* add data to the ringbuffer */
+    return ringbuffer_add(&handle->rbuf, pvItem, xItemSize) == xItemSize;
+}

cpu/esp_common/include/freertos/ringbuf.h

@@ -21,6 +21,33 @@
 extern "C" {
 #endif
 
+#define RINGBUF_TYPE_BYTEBUF    2
+
+typedef unsigned RingbufferType_t;
+typedef void * RingbufHandle_t;
+
+RingbufHandle_t xRingbufferCreate(size_t xBufferSize, RingbufferType_t xBufferType);
+
+void vRingbufferDelete(RingbufHandle_t xRingbuffer);
+
+void *xRingbufferReceiveUpTo(RingbufHandle_t xRingbuffer,
+                             size_t *pxItemSize,
+                             TickType_t xTicksToWait,
+                             size_t xMaxSize);
+
+BaseType_t xRingbufferSendFromISR(RingbufHandle_t xRingbuffer,
+                                  const void *pvItem,
+                                  size_t xItemSize,
+                                  BaseType_t *pxHigherPriorityTaskWoken);
+
+void *xRingbufferReceiveUpToFromISR(RingbufHandle_t xRingbuffer,
+                                    size_t *pxItemSize, size_t xMaxSize);
+
+void *xRingbufferReceiveFromISR(RingbufHandle_t xRingbuffer, size_t *pxItemSize);
+
+void vRingbufferReturnItemFromISR(RingbufHandle_t xRingbuffer, void *pvItem,
+                                  BaseType_t *pxHigherPriorityTaskWoken);
+
 #ifdef __cplusplus
 }
 #endif