sys: add usb_board_reset module

sys/include/usb_board_reset.h

@@ -0,0 +1,56 @@
+/*
+ * Copyright (C) 2020 Inria
+ *
+ * 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.
+ */
+
+/**
+ * @defgroup    sys_usb_board_reset Board reset via USB CDC ACM
+ * @ingroup     sys
+ * @brief       Trigger a board reset via USB CDC ACM
+ *
+ * @{
+ *
+ * @file
+ * @author      Alexandre Abadie <alexandre.abadie@inria.fr>
+ */
+
+#ifndef USB_BOARD_RESET_H
+#define USB_BOARD_RESET_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <inttypes.h>
+
+#include "usb/usbus/cdc/acm.h"
+
+/**
+ * @brief   USB coding callback used to trigger the board reset
+ *
+ * @param[in] cdcacm    Pointer to the cdcacm device
+ * @param[in] baud      Baudrate used by the client. Only 1200 baud is taken into account
+ * @param[in] bits      Number of bit mode used by the client
+ * @param[in] parity    Parity mode used by the client
+ * @param[in] stop      Stop bit mode used by the client
+ *
+ * @return  Always return 0
+ */
+int usb_board_reset_coding_cb(usbus_cdcacm_device_t *cdcacm,
+                              uint32_t baud, uint8_t bits,
+                              uint8_t parity, uint8_t stop);
+
+/**
+ * @brief   Trigger a simple reset, back to the application
+ */
+void usb_board_reset_in_application(void);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* USB_BOARD_RESET_H */
+/** @} */

sys/usb_board_reset/Makefile

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+include $(RIOTBASE)/Makefile.base

sys/usb_board_reset/usb_board_reset.c

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+/*
+ * Copyright (C) 2020 Inria
+ *
+ * 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.
+ */
+
+/**
+ * @ingroup sys
+ * @{
+ * @file
+ *
+ * @author  Alexandre Abadie <alexandre.abadie@inria.fr>
+ * @}
+ */
+
+#define USB_H_USER_IS_RIOT_INTERNAL
+
+#include "log.h"
+
+#include "usb/usbus/cdc/acm.h"
+#include "usb_board_reset.h"
+
+#include "periph/pm.h"
+
+#ifndef RESET_IN_BOOTLOADER_TRIGGER_BAUDRATE
+#define RESET_IN_BOOTLOADER_TRIGGER_BAUDRATE    (1200U)
+#endif
+
+#ifndef RESET_IN_APPLICATION_TRIGGER_BAUDRATE
+#define RESET_IN_APPLICATION_TRIGGER_BAUDRATE   (600U)
+#endif
+
+void usb_board_reset_in_bootloader(void);
+
+int usb_board_reset_coding_cb(usbus_cdcacm_device_t *cdcacm,
+                              uint32_t baud, uint8_t bits,
+                              uint8_t parity, uint8_t stop)
+{
+    (void)cdcacm;
+    (void)bits;
+    (void)parity;
+    (void)stop;
+    switch (baud) {
+        case RESET_IN_BOOTLOADER_TRIGGER_BAUDRATE:
+            LOG_DEBUG("[cdc-acm-stdio] reset in bootloader");
+            usb_board_reset_in_bootloader();
+            break;
+        case RESET_IN_APPLICATION_TRIGGER_BAUDRATE:
+            LOG_DEBUG("[cdc-acm-stdio] reset in application");
+            usb_board_reset_in_application();
+            break;
+        default:
+            (void)baud;
+            break;
+    }
+
+    return 0;
+}
+
+void usb_board_reset_in_application(void)
+{
+    pm_reboot();
+    while (1) {}
+}