Merge branch 'bugfix/usb_serial_jtag_write_return_val_v5.1' into 'rel…

…ease/v5.1'

bugfix(usb_serial_jtag): Fix usb_serial_jtag wrong return value, vfs lose data randomly (backport v5.1)

See merge request espressif/esp-idf!26174

components/driver/usb_serial_jtag/usb_serial_jtag.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2021-2022 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2021-2023 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -27,21 +27,24 @@ typedef struct{
     // RX parameters
     RingbufHandle_t rx_ring_buf;        /*!< RX ring buffer handler */
     uint32_t rx_buf_size;               /*!< TX buffer size */
-    uint8_t rx_data_buf[64];            /*!< Data buffer to stash FIFO data */
+    uint8_t rx_data_buf[USB_SER_JTAG_ENDP_SIZE];            /*!< Data buffer to stash FIFO data */
 
     // TX parameters
     uint32_t tx_buf_size;               /*!< TX buffer size */
     RingbufHandle_t tx_ring_buf;        /*!< TX ring buffer handler */
+    uint8_t tx_data_buf[USB_SER_JTAG_ENDP_SIZE];  /*!< Data buffer to stash TX FIFO data */
+    size_t tx_stash_cnt;                          /*!< Number of stashed TX FIFO bytes */
 } usb_serial_jtag_obj_t;
 
 static usb_serial_jtag_obj_t *p_usb_serial_jtag_obj = NULL;
 
 static const char* USB_SERIAL_JTAG_TAG = "usb_serial_jtag";
 
-static void usb_serial_jtag_write_and_flush(const uint8_t *buf, uint32_t wr_len)
+static size_t usb_serial_jtag_write_and_flush(const uint8_t *buf, uint32_t wr_len)
 {
-    usb_serial_jtag_ll_write_txfifo(buf, wr_len);
+    size_t size = usb_serial_jtag_ll_write_txfifo(buf, wr_len);
     usb_serial_jtag_ll_txfifo_flush();
+    return size;
 }
 
 static void usb_serial_jtag_isr_handler_default(void *arg) {
@@ -50,19 +53,53 @@ static void usb_serial_jtag_isr_handler_default(void *arg) {
     usbjtag_intr_status = usb_serial_jtag_ll_get_intsts_mask();
 
     if (usbjtag_intr_status & USB_SERIAL_JTAG_INTR_SERIAL_IN_EMPTY) {
-        // Interrupt tells us the host picked up the data we sent. If we have more data, we can put it in the buffer and the host will pick that up next.
+        // Interrupt tells us the host picked up the data we sent.
+        // If we have more data, we can put it in the buffer and the host will pick that up next.
         // Send data in isr.
+        // If the hardware fifo is available, write in it. Otherwise, do nothing.
         if (usb_serial_jtag_ll_txfifo_writable() == 1) {
             // We disable the interrupt here so that the interrupt won't be triggered if there is no data to send.
             usb_serial_jtag_ll_disable_intr_mask(USB_SERIAL_JTAG_INTR_SERIAL_IN_EMPTY);
             size_t queued_size;
-            uint8_t *queued_buff = (uint8_t *)xRingbufferReceiveUpToFromISR(p_usb_serial_jtag_obj->tx_ring_buf, &queued_size, 64);
-            // If the hardware fifo is avaliable, write in it. Otherwise, do nothing.
-            if (queued_buff != NULL) {  //Although tx_queued_bytes may be larger than 0. We may have interrupt before xRingbufferSend() was called.
-                //Copy the queued buffer into the TX FIFO
-                usb_serial_jtag_ll_clr_intsts_mask(USB_SERIAL_JTAG_INTR_SERIAL_IN_EMPTY);
-                usb_serial_jtag_write_and_flush(queued_buff, queued_size);
-                vRingbufferReturnItemFromISR(p_usb_serial_jtag_obj->tx_ring_buf, queued_buff, &xTaskWoken);
+            uint8_t *queued_buff = NULL;
+            bool is_stashed_data = false;
+            if (p_usb_serial_jtag_obj->tx_stash_cnt != 0) {
+                // Send stashed tx bytes before reading bytes from ring buffer
+                queued_buff = p_usb_serial_jtag_obj->tx_data_buf;
+                queued_size = p_usb_serial_jtag_obj->tx_stash_cnt;
+                is_stashed_data = true;
+            } else {
+                // Max 64 data payload size in a single EndPoint
+                queued_buff = (uint8_t *)xRingbufferReceiveUpToFromISR(p_usb_serial_jtag_obj->tx_ring_buf, &queued_size, USB_SER_JTAG_ENDP_SIZE);
+            }
+
+            usb_serial_jtag_ll_clr_intsts_mask(USB_SERIAL_JTAG_INTR_SERIAL_IN_EMPTY);
+
+            if (queued_buff != NULL) {
+
+                // Although tx_queued_bytes may be larger than 0, we may have
+                // interrupted before xRingbufferSend() was called.
+                // Copy the queued buffer into the TX FIFO
+
+                // On ringbuffer wrap-around the size can be 0 even though the buffer returned is not NULL
+                if (queued_size > 0) {
+                    uint32_t sent_size = usb_serial_jtag_write_and_flush(queued_buff, queued_size);
+
+                    if (sent_size < queued_size) {
+                        // Not all bytes could be sent at once, stash the unwritten bytes in a tx buffer
+                        // stash_size will not larger than USB_SER_JTAG_ENDP_SIZE because queued_size is got from xRingbufferReceiveUpToFromISR
+                        size_t stash_size = queued_size - sent_size;
+                        memcpy(p_usb_serial_jtag_obj->tx_data_buf, &queued_buff[sent_size], stash_size);
+                        p_usb_serial_jtag_obj->tx_stash_cnt = stash_size;
+                    } else {
+                        p_usb_serial_jtag_obj->tx_stash_cnt = 0;
+                        // assert if sent_size is larger than queued_size.
+                        assert(sent_size <= queued_size);
+                    }
+                }
+                if (is_stashed_data == false) {
+                    vRingbufferReturnItemFromISR(p_usb_serial_jtag_obj->tx_ring_buf, queued_buff, &xTaskWoken);
+                }
                 usb_serial_jtag_ll_ena_intr_mask(USB_SERIAL_JTAG_INTR_SERIAL_IN_EMPTY);
             }
         } else {
@@ -93,6 +130,7 @@ esp_err_t usb_serial_jtag_driver_install(usb_serial_jtag_driver_config_t *usb_se
     p_usb_serial_jtag_obj = (usb_serial_jtag_obj_t*) heap_caps_calloc(1, sizeof(usb_serial_jtag_obj_t), MALLOC_CAP_INTERNAL|MALLOC_CAP_8BIT);
     p_usb_serial_jtag_obj->rx_buf_size = usb_serial_jtag_config->rx_buffer_size;
     p_usb_serial_jtag_obj->tx_buf_size = usb_serial_jtag_config->tx_buffer_size;
+    p_usb_serial_jtag_obj->tx_stash_cnt = 0;
     if (p_usb_serial_jtag_obj == NULL) {
         ESP_LOGE(USB_SERIAL_JTAG_TAG, "memory allocate error");
         err = ESP_ERR_NO_MEM;
@@ -163,10 +201,10 @@ int usb_serial_jtag_write_bytes(const void* src, size_t size, TickType_t ticks_t
 
     const uint8_t *buff = (const uint8_t *)src;
     // Blocking method, Sending data to ringbuffer, and handle the data in ISR.
-    xRingbufferSend(p_usb_serial_jtag_obj->tx_ring_buf, (void*) (buff), size, ticks_to_wait);
+    BaseType_t result = xRingbufferSend(p_usb_serial_jtag_obj->tx_ring_buf, (void*) (buff), size, ticks_to_wait);
     // Now trigger the ISR to read data from the ring buffer.
-   usb_serial_jtag_ll_ena_intr_mask(USB_SERIAL_JTAG_INTR_SERIAL_IN_EMPTY);
-   return size;
+    usb_serial_jtag_ll_ena_intr_mask(USB_SERIAL_JTAG_INTR_SERIAL_IN_EMPTY);
+    return (result == pdFALSE) ? 0 : size;
 }
 
 esp_err_t usb_serial_jtag_driver_uninstall(void)