From 422dd808e4fe94d0b77be3687123840d71f989c1 Mon Sep 17 00:00:00 2001 From: Guillaume Souchere Date: Mon, 9 Jun 2025 09:03:40 +0200 Subject: [PATCH] feat(usb_serial_jtag): Update vfs read to be POSIX compliant The function now returns with available data in blocking mode instead of waiting for the requested size to be available before returning. --- .../include/driver/usb_serial_jtag.h | 30 ++++++- .../src/usb_serial_jtag.c | 30 +++++++ .../src/usb_serial_jtag_vfs.c | 83 +++++++++++++------ 3 files changed, 115 insertions(+), 28 deletions(-) diff --git a/components/esp_driver_usb_serial_jtag/include/driver/usb_serial_jtag.h b/components/esp_driver_usb_serial_jtag/include/driver/usb_serial_jtag.h index 93aec7a27e..867411637a 100644 --- a/components/esp_driver_usb_serial_jtag/include/driver/usb_serial_jtag.h +++ b/components/esp_driver_usb_serial_jtag/include/driver/usb_serial_jtag.h @@ -1,5 +1,5 @@ /* - * SPDX-FileCopyrightText: 2021-2024 Espressif Systems (Shanghai) CO LTD + * SPDX-FileCopyrightText: 2021-2025 Espressif Systems (Shanghai) CO LTD * * SPDX-License-Identifier: Apache-2.0 */ @@ -96,6 +96,34 @@ esp_err_t usb_serial_jtag_driver_uninstall(void); */ bool usb_serial_jtag_is_connected(void); +/** + * @brief Get information whether the USB serial JTAG driver is installed or not + * + * @return True if driver is installed and False if driver not installed + */ +bool usb_serial_jtag_is_driver_installed(void); + +/** + * @brief Return the number of bytes available for reading + * + * @return the number of bytes available for reading in the buffer + */ +size_t usb_serial_jtag_get_read_bytes_available(void); + +/** + * @brief Return the readiness status of the driver for read operation + * + * @return true if driver read ready, false if not + */ +bool usb_serial_jtag_read_ready(void); + +/** + * @brief Return the readiness status of the driver for write operation + * + * @return true if driver is write ready, false if not + */ +bool usb_serial_jtag_write_ready(void); + #ifdef __cplusplus } #endif diff --git a/components/esp_driver_usb_serial_jtag/src/usb_serial_jtag.c b/components/esp_driver_usb_serial_jtag/src/usb_serial_jtag.c index 455ea54300..e326246367 100644 --- a/components/esp_driver_usb_serial_jtag/src/usb_serial_jtag.c +++ b/components/esp_driver_usb_serial_jtag/src/usb_serial_jtag.c @@ -256,3 +256,33 @@ esp_err_t usb_serial_jtag_driver_uninstall(void) p_usb_serial_jtag_obj = NULL; return ESP_OK; } + +bool usb_serial_jtag_is_driver_installed(void) +{ + return (p_usb_serial_jtag_obj != NULL); +} + +size_t usb_serial_jtag_get_read_bytes_available(void) +{ + // sign the the driver is read ready is that data is waiting in the RX ringbuffer + UBaseType_t bytes_available = 0; + if (usb_serial_jtag_is_driver_installed()) { + vRingbufferGetInfo(p_usb_serial_jtag_obj->rx_ring_buf, NULL, NULL, NULL, NULL, &bytes_available); + if (bytes_available <= 0) { + return 0; + } + } + + return (size_t)bytes_available; +} + +bool usb_serial_jtag_read_ready(void) +{ + return usb_serial_jtag_get_read_bytes_available() != 0; +} + +bool usb_serial_jtag_write_ready(void) +{ + // sign that the driver is write ready is that the TX ring buffer is not full + return (xRingbufferGetCurFreeSize(p_usb_serial_jtag_obj->tx_ring_buf) > 0); +} diff --git a/components/esp_driver_usb_serial_jtag/src/usb_serial_jtag_vfs.c b/components/esp_driver_usb_serial_jtag/src/usb_serial_jtag_vfs.c index 6af6bf02f6..1562eee96f 100644 --- a/components/esp_driver_usb_serial_jtag/src/usb_serial_jtag_vfs.c +++ b/components/esp_driver_usb_serial_jtag/src/usb_serial_jtag_vfs.c @@ -1,5 +1,5 @@ /* - * SPDX-FileCopyrightText: 2015-2024 Espressif Systems (Shanghai) CO LTD + * SPDX-FileCopyrightText: 2015-2025 Espressif Systems (Shanghai) CO LTD * * SPDX-License-Identifier: Apache-2.0 */ @@ -189,39 +189,68 @@ static void usb_serial_jtag_return_char(int fd, int c) static ssize_t usb_serial_jtag_read(int fd, void* data, size_t size) { - assert(fd == USJ_LOCAL_FD); char *data_c = (char *) data; size_t received = 0; + size_t available_size = 0; + int c = NONE; // store the read char _lock_acquire_recursive(&s_ctx.read_lock); - while (received < size) { - int c = usb_serial_jtag_read_char(fd); - if (c == '\r') { - if (s_ctx.rx_mode == ESP_LINE_ENDINGS_CR) { - c = '\n'; - } else if (s_ctx.rx_mode == ESP_LINE_ENDINGS_CRLF) { - /* look ahead */ - int c2 = usb_serial_jtag_read_char(fd); - if (c2 == NONE) { - /* could not look ahead, put the current character back */ - usb_serial_jtag_return_char(fd, c); - break; - } - if (c2 == '\n') { - /* this was \r\n sequence. discard \r, return \n */ + // if blocking read, wait for data to be available + if (!s_ctx.non_blocking) { + c = usb_serial_jtag_read_char(fd); + } + + // find the actual fetch size + available_size += usb_serial_jtag_get_read_bytes_available(); + if (c != NONE) { + available_size++; + } + if (s_ctx.peek_char != NONE) { + available_size++; + } + size_t fetch_size = MIN(available_size, size); + + if (fetch_size > 0) { + do { + if (c == NONE) { // for non-O_NONBLOCK mode, there is already a pre-fetched char + c = usb_serial_jtag_read_char(fd); + } + assert(c != NONE); + + if (c == '\r') { + if (s_ctx.rx_mode == ESP_LINE_ENDINGS_CR) { c = '\n'; - } else { - /* \r followed by something else. put the second char back, - * it will be processed on next iteration. return \r now. - */ - usb_serial_jtag_return_char(fd, c2); + } else if (s_ctx.rx_mode == ESP_LINE_ENDINGS_CRLF) { + /* look ahead */ + int c2 = usb_serial_jtag_read_char(fd); + fetch_size--; + if (c2 == NONE) { + /* could not look ahead, put the current character back */ + usb_serial_jtag_return_char(fd, c); + c = NONE; + break; + } + if (c2 == '\n') { + /* this was \r\n sequence. discard \r, return \n */ + c = '\n'; + } else { + /* \r followed by something else. put the second char back, + * it will be processed on next iteration. return \r now. + */ + usb_serial_jtag_return_char(fd, c2); + fetch_size++; + } } } - } else if (c == NONE) { - break; - } - data_c[received] = (char) c; - ++received; + + data_c[received] = (char) c; + ++received; + c = NONE; + } while (received < fetch_size); + } + + if (c != NONE) { // fetched, but not used + usb_serial_jtag_return_char(fd, c); } _lock_release_recursive(&s_ctx.read_lock); if (received > 0) {