nrf: Add tinyusb support for nrf52840.

Add nrf-port finyusb driver files. USB CDC can be activated
by board configuration files using the MICROPY_HW_USB_CDC.

Updating BLE driver, Makefile, nrfx-glue and main.c to plug
in the tinyusb stack.

10 files changed, 485 insertions, 1 deletions

diff --git a/ports/nrf/Makefile b/ports/nrf/Makefile
index aa6c189aa..46dd8c8d7 100644
--- a/ports/nrf/Makefile
+++ b/ports/nrf/Makefile
@@ -66,6 +66,7 @@ INC += -I../../lib/nrfx/drivers
 INC += -I../../lib/nrfx/drivers/include
 INC += -I../../lib/nrfx/mdk
 INC += -I../../lib/nrfx/hal
+INC += -I../../lib/nrfx/drivers/src/
 
 MCU_VARIANT_UPPER = $(shell echo $(MCU_VARIANT) | tr '[:lower:]' '[:upper:]')
 MCU_SUB_VARIANT_UPPER = $(shell echo $(MCU_SUB_VARIANT) | tr '[:lower:]' '[:upper:]')
@@ -183,6 +184,8 @@ SRC_NRFX += $(addprefix lib/nrfx/drivers/src/,\
 	nrfx_pwm.c \
 	nrfx_gpiote.c \
 	nrfx_nvmc.c \
+	nrfx_power.c \
+	nrfx_clock.c \
 	)
 
 SRC_C += \
@@ -198,6 +201,34 @@ SRC_C += \
 	drivers/bluetooth/ble_drv.c \
 	drivers/bluetooth/ble_uart.c \
 
+ifeq ($(MCU_SUB_VARIANT), nrf52840)
+
+INC += -I./drivers/usb
+INC += -I../../lib/tinyusb/src
+
+
+# If SoftDevice is selected.
+ifneq ($(SD), )
+# For external tinyusb drivers to enable SoftDevice mode.
+CFLAGS += -DSOFTDEVICE_PRESENT
+endif
+
+SRC_C += $(addprefix drivers/usb/,\
+	usb_cdc.c \
+	usb_descriptors.c \
+	)
+
+SRC_C += $(addprefix lib/tinyusb/src/,\
+	common/tusb_fifo.c \
+	device/usbd.c \
+	device/usbd_control.c \
+	class/cdc/cdc_device.c \
+	tusb.c \
+	portable/nordic/nrf5x/dcd_nrf5x.c \
+	portable/nordic/nrf5x/hal_nrf5x.c \
+	)
+endif
+
 DRIVERS_SRC_C += $(addprefix modules/,\
 	machine/modmachine.c \
 	machine/uart.c \
diff --git a/ports/nrf/drivers/bluetooth/ble_drv.c b/ports/nrf/drivers/bluetooth/ble_drv.c
index e01d11848..4401369f8 100644
--- a/ports/nrf/drivers/bluetooth/ble_drv.c
+++ b/ports/nrf/drivers/bluetooth/ble_drv.c
@@ -40,6 +40,10 @@
 #include "mphalport.h"
 
 
+#if MICROPY_HW_USB_CDC
+#include "usb_cdc.h"
+#endif
+
 #define BLE_DRIVER_VERBOSE 0
 
 #if BLE_DRIVER_VERBOSE
@@ -952,6 +956,10 @@ static void sd_evt_handler(uint32_t evt_id) {
             // unhandled event!
             break;
     }
+#if MICROPY_HW_USB_CDC
+    // Farward SOC events to USB CDC driver.
+    usb_cdc_sd_event_handler(evt_id);
+#endif
 }
 
 static void ble_evt_handler(ble_evt_t * p_ble_evt) {
diff --git a/ports/nrf/drivers/usb/tusb_config.h b/ports/nrf/drivers/usb/tusb_config.h
new file mode 100644
index 000000000..619578ad6
--- /dev/null
+++ b/ports/nrf/drivers/usb/tusb_config.h
@@ -0,0 +1,44 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2019 Damien P. George
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+#ifndef MICROPY_INCLUDED_NRF_TUSB_CONFIG_H
+#define MICROPY_INCLUDED_NRF_TUSB_CONFIG_H
+
+// Common configuration
+
+#define CFG_TUSB_MCU                OPT_MCU_NRF5X
+#define CFG_TUSB_RHPORT0_MODE       OPT_MODE_DEVICE
+
+#define CFG_TUSB_MEM_SECTION
+#define CFG_TUSB_MEM_ALIGN          TU_ATTR_ALIGNED(4)
+
+// Device configuration
+
+#define CFG_TUD_ENDOINT0_SIZE       (64)
+#define CFG_TUD_CDC                 (1)
+#define CFG_TUD_CDC_RX_BUFSIZE      (64)
+#define CFG_TUD_CDC_TX_BUFSIZE      (64)
+
+#endif // MICROPY_INCLUDED_NRF_TUSB_CONFIG_H
diff --git a/ports/nrf/drivers/usb/usb_cdc.c b/ports/nrf/drivers/usb/usb_cdc.c
new file mode 100644
index 000000000..c90bced6b
--- /dev/null
+++ b/ports/nrf/drivers/usb/usb_cdc.c
@@ -0,0 +1,226 @@
+/*
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2019 Ha Thach (tinyusb.org)
+ * Copyright (c) 2019 Glenn Ruben Bakke
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * This file is part of the TinyUSB stack.
+ */
+
+#include "py/mphal.h"
+
+#if MICROPY_HW_USB_CDC
+
+#include "tusb.h"
+#include "nrfx.h"
+#include "nrfx_power.h"
+#include "nrfx_uart.h"
+#include "py/ringbuf.h"
+
+#ifdef BLUETOOTH_SD
+#include "nrf_sdm.h"
+#include "nrf_soc.h"
+#include "ble_drv.h"
+#endif
+
+extern void tusb_hal_nrf_power_event(uint32_t event);
+
+static void cdc_task(void);
+
+static uint8_t rx_ringbuf_array[1024];
+static uint8_t tx_ringbuf_array[1024];
+static volatile ringbuf_t rx_ringbuf;
+static volatile ringbuf_t tx_ringbuf;
+
+static void board_init(void) {
+    // Config clock source.
+#ifndef BLUETOOTH_SD
+    NRF_CLOCK->LFCLKSRC = (uint32_t)((CLOCK_LFCLKSRC_SRC_Xtal << CLOCK_LFCLKSRC_SRC_Pos) & CLOCK_LFCLKSRC_SRC_Msk);
+    NRF_CLOCK->TASKS_LFCLKSTART = 1UL;
+#endif
+
+    // Priorities 0, 1, 4 (nRF52) are reserved for SoftDevice
+    // 2 is highest for application
+    NRFX_IRQ_PRIORITY_SET(USBD_IRQn, 2);
+
+    // USB power may already be ready at this time -> no event generated
+    // We need to invoke the handler based on the status initially
+    uint32_t usb_reg;
+
+#ifdef BLUETOOTH_SD
+    uint8_t sd_en = false;
+    sd_softdevice_is_enabled(&sd_en);
+
+    if (sd_en) {
+        sd_power_usbdetected_enable(true);
+        sd_power_usbpwrrdy_enable(true);
+        sd_power_usbremoved_enable(true);
+
+        sd_power_usbregstatus_get(&usb_reg);
+    } else
+#endif
+    {
+        // Power module init
+        const nrfx_power_config_t pwr_cfg = { 0 };
+        nrfx_power_init(&pwr_cfg);
+
+        // Register tusb function as USB power handler
+        const nrfx_power_usbevt_config_t config = { .handler = (nrfx_power_usb_event_handler_t) tusb_hal_nrf_power_event };
+        nrfx_power_usbevt_init(&config);
+
+        nrfx_power_usbevt_enable();
+
+        usb_reg = NRF_POWER->USBREGSTATUS;
+    }
+
+    if (usb_reg & POWER_USBREGSTATUS_VBUSDETECT_Msk) {
+        tusb_hal_nrf_power_event(NRFX_POWER_USB_EVT_DETECTED);
+    }
+
+#ifndef BLUETOOTH_SD
+    if (usb_reg & POWER_USBREGSTATUS_OUTPUTRDY_Msk) {
+        tusb_hal_nrf_power_event(NRFX_POWER_USB_EVT_READY);
+    }
+#endif
+}
+
+static bool cdc_rx_any(void) {
+    return rx_ringbuf.iput != rx_ringbuf.iget;
+}
+
+static int cdc_rx_char(void) {
+    return ringbuf_get((ringbuf_t*)&rx_ringbuf);
+}
+
+static bool cdc_tx_any(void) {
+    return tx_ringbuf.iput != tx_ringbuf.iget;
+}
+
+static int cdc_tx_char(void) {
+    return ringbuf_get((ringbuf_t*)&tx_ringbuf);
+}
+
+static void cdc_task(void)
+{
+    if ( tud_cdc_connected() ) {
+        // connected and there are data available
+        while (tud_cdc_available()) {
+            int c;
+            uint32_t count = tud_cdc_read(&c, 1);
+            (void)count;
+            ringbuf_put((ringbuf_t*)&rx_ringbuf, c);
+        }
+
+        int chars = 0;
+        while (cdc_tx_any()) {
+            if (chars < 64) {
+               tud_cdc_write_char(cdc_tx_char());
+               chars++;
+            } else {
+               chars = 0;
+               tud_cdc_write_flush();
+            }
+        }
+
+        tud_cdc_write_flush();
+    }
+}
+
+static void usb_cdc_loop(void) {
+    tud_task();
+    cdc_task();
+}
+
+int usb_cdc_init(void)
+{
+    static bool initialized = false;
+    if (!initialized) {
+
+#if BLUETOOTH_SD
+        // Initialize the clock and BLE stack.
+        ble_drv_stack_enable();
+#endif
+
+        board_init();
+        initialized = true;
+    }
+
+    rx_ringbuf.buf = rx_ringbuf_array;
+    rx_ringbuf.size = sizeof(rx_ringbuf_array);
+    rx_ringbuf.iget = 0;
+    rx_ringbuf.iput = 0;
+
+    tx_ringbuf.buf = tx_ringbuf_array;
+    tx_ringbuf.size = sizeof(tx_ringbuf_array);
+    tx_ringbuf.iget = 0;
+    tx_ringbuf.iput = 0;
+
+    tusb_init();
+
+    return 0;
+}
+
+#ifdef BLUETOOTH_SD
+// process SOC event from SD
+void usb_cdc_sd_event_handler(uint32_t soc_evt) {
+    /*------------- usb power event handler -------------*/
+    int32_t usbevt = (soc_evt == NRF_EVT_POWER_USB_DETECTED   ) ? NRFX_POWER_USB_EVT_DETECTED:
+                     (soc_evt == NRF_EVT_POWER_USB_POWER_READY) ? NRFX_POWER_USB_EVT_READY   :
+                     (soc_evt == NRF_EVT_POWER_USB_REMOVED    ) ? NRFX_POWER_USB_EVT_REMOVED : -1;
+
+    if (usbevt >= 0) {
+        tusb_hal_nrf_power_event(usbevt);
+    }
+}
+#endif
+
+int mp_hal_stdin_rx_chr(void) {
+    for (;;) {
+        usb_cdc_loop();
+        if (cdc_rx_any()) {
+            return cdc_rx_char();
+        }
+    }
+
+    return 0;
+}
+
+void mp_hal_stdout_tx_strn(const char *str, mp_uint_t len) {
+
+    for (const char *top = str + len; str < top; str++) {
+        ringbuf_put((ringbuf_t*)&tx_ringbuf, *str);
+        usb_cdc_loop();
+    }
+}
+
+void mp_hal_stdout_tx_strn_cooked(const char *str, mp_uint_t len) {
+
+    for (const char *top = str + len; str < top; str++) {
+        if (*str == '\n') {
+            ringbuf_put((ringbuf_t*)&tx_ringbuf, '\r');
+            usb_cdc_loop();
+        }
+        ringbuf_put((ringbuf_t*)&tx_ringbuf, *str);
+        usb_cdc_loop();
+    }
+}
+
+#endif // MICROPY_HW_USB_CDC
diff --git a/ports/nrf/drivers/usb/usb_cdc.h b/ports/nrf/drivers/usb/usb_cdc.h
new file mode 100644
index 000000000..7cd94f85b
--- /dev/null
+++ b/ports/nrf/drivers/usb/usb_cdc.h
@@ -0,0 +1,40 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2019 Glenn Ruben Bakke
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef NRF_DRIVERS_USB_CDC_H__
+#define NRF_DRIVERS_USB_CDC_H__
+
+#include "tusb.h"
+
+void usb_cdc_init(void);
+
+void usb_cdc_loop(void);
+int  usb_cdc_read_char(void);
+void usb_cdc_write_char(char c);
+
+void usb_cdc_sd_event_handler(uint32_t soc_evt);
+
+#endif // NRF_DRIVERS_USB_CDC_H__
diff --git a/ports/nrf/drivers/usb/usb_descriptors.c b/ports/nrf/drivers/usb/usb_descriptors.c
new file mode 100644
index 000000000..a061302d6
--- /dev/null
+++ b/ports/nrf/drivers/usb/usb_descriptors.c
@@ -0,0 +1,114 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2019 Damien P. George
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "tusb.h"
+
+#define USBD_VID (0xf055)
+#define USBD_PID (0x9802)
+
+#define USBD_DESC_LEN (TUD_CONFIG_DESC_LEN + TUD_CDC_DESC_LEN)
+#define USBD_MAX_POWER_MA (250)
+
+#define USBD_ITF_CDC (0) // needs 2 interfaces
+#define USBD_ITF_MAX (2)
+
+#define USBD_CDC_EP_CMD (0x81)
+#define USBD_CDC_EP_OUT (0x02)
+#define USBD_CDC_EP_IN (0x82)
+#define USBD_CDC_CMD_MAX_SIZE (8)
+
+#define USBD_STR_0 (0x00)
+#define USBD_STR_MANUF (0x01)
+#define USBD_STR_PRODUCT (0x02)
+#define USBD_STR_SERIAL (0x03)
+#define USBD_STR_CDC (0x04)
+
+// Note: descriptors returned from callbacks must exist long enough for transfer to complete
+
+static const tusb_desc_device_t usbd_desc_device = {
+    .bLength            = sizeof(tusb_desc_device_t),
+    .bDescriptorType    = TUSB_DESC_DEVICE,
+    .bcdUSB             = 0x0200,
+    .bDeviceClass       = TUSB_CLASS_MISC,
+    .bDeviceSubClass    = MISC_SUBCLASS_COMMON,
+    .bDeviceProtocol    = MISC_PROTOCOL_IAD,
+    .bMaxPacketSize0    = CFG_TUD_ENDOINT0_SIZE,
+    .idVendor           = USBD_VID,
+    .idProduct          = USBD_PID,
+    .bcdDevice          = 0x0100,
+    .iManufacturer      = USBD_STR_MANUF,
+    .iProduct           = USBD_STR_PRODUCT,
+    .iSerialNumber      = USBD_STR_SERIAL,
+    .bNumConfigurations = 1,
+};
+
+static const uint8_t usbd_desc_cfg[USBD_DESC_LEN] = {
+    TUD_CONFIG_DESCRIPTOR(USBD_ITF_MAX, USBD_STR_0, USBD_DESC_LEN,
+        TUSB_DESC_CONFIG_ATT_REMOTE_WAKEUP, USBD_MAX_POWER_MA),
+
+    TUD_CDC_DESCRIPTOR(USBD_ITF_CDC, USBD_STR_CDC, USBD_CDC_EP_CMD,
+        USBD_CDC_CMD_MAX_SIZE, USBD_CDC_EP_OUT, USBD_CDC_EP_IN, CFG_TUD_CDC_RX_BUFSIZE),
+};
+
+static const char *const usbd_desc_str[] = {
+    [USBD_STR_MANUF] = "MicroPython",
+    [USBD_STR_PRODUCT] = "Board in FS mode",
+    [USBD_STR_SERIAL] = "000000000000", // TODO
+    [USBD_STR_CDC] = "Board CDC",
+};
+
+const uint8_t *tud_descriptor_device_cb(void) {
+    return (const uint8_t*)&usbd_desc_device;
+}
+
+const uint8_t *tud_descriptor_configuration_cb(uint8_t index) {
+    (void)index;
+    return usbd_desc_cfg;
+}
+
+const uint16_t *tud_descriptor_string_cb(uint8_t index) {
+    #define DESC_STR_MAX (20)
+    static uint16_t desc_str[DESC_STR_MAX];
+
+    uint8_t len;
+    if (index == 0) {
+        desc_str[1] = 0x0409; // supported language is English
+        len = 1;
+    } else {
+        if (index >= sizeof(usbd_desc_str) / sizeof(usbd_desc_str[0])) {
+            return NULL;
+        }
+        const char* str = usbd_desc_str[index];
+        for (len = 0; len < DESC_STR_MAX - 1 && str[len]; ++len) {
+            desc_str[1 + len] = str[len];
+        }
+    }
+
+    // first byte is len, second byte is string type
+    desc_str[0] = TUD_DESC_STR_HEADER(len);
+
+    return desc_str;
+}
diff --git a/ports/nrf/main.c b/ports/nrf/main.c
index e82cfcf58..ce8512aee 100644
--- a/ports/nrf/main.c
+++ b/ports/nrf/main.c
@@ -70,6 +70,10 @@
 #include "softpwm.h"
 #endif
 
+#if MICROPY_HW_USB_CDC
+#include "usb_cdc.h"
+#endif
+
 void do_str(const char *src, mp_parse_input_kind_t input_kind) {
     mp_lexer_t *lex = mp_lexer_new_from_str_len(MP_QSTR__lt_stdin_gt_, src, strlen(src), 0);
     if (lex == NULL) {
@@ -121,6 +125,7 @@ soft_reset:
 
     readline_init0();
 
+
 #if MICROPY_PY_MACHINE_HW_SPI
     spi_init0();
 #endif
@@ -149,7 +154,7 @@ soft_reset:
     uart_init0();
 #endif
 
-#if (MICROPY_PY_BLE_NUS == 0)
+#if (MICROPY_PY_BLE_NUS == 0) && (MICROPY_HW_USB_CDC == 0)
     {
         mp_obj_t args[2] = {
             MP_OBJ_NEW_SMALL_INT(0),
@@ -231,6 +236,10 @@ led_state(1, 0);
     pyexec_file_if_exists("main.py");
 #endif
 
+#if MICROPY_HW_USB_CDC
+    usb_cdc_init();
+#endif
+
     for (;;) {
         if (pyexec_mode_kind == PYEXEC_MODE_RAW_REPL) {
             if (pyexec_raw_repl() != 0) {
diff --git a/ports/nrf/mphalport.c b/ports/nrf/mphalport.c
index bf8969708..b915c23e4 100644
--- a/ports/nrf/mphalport.c
+++ b/ports/nrf/mphalport.c
@@ -62,7 +62,9 @@ uintptr_t mp_hal_stdio_poll(uintptr_t poll_flags) {
     }
     return ret;
 }
+#endif
 
+#if !MICROPY_PY_BLE_NUS && !MICROPY_HW_USB_CDC
 int mp_hal_stdin_rx_chr(void) {
     for (;;) {
         if (MP_STATE_PORT(board_stdio_uart) != NULL && uart_rx_any(MP_STATE_PORT(board_stdio_uart))) {
diff --git a/ports/nrf/nrfx_config.h b/ports/nrf/nrfx_config.h
index 99085a2fe..505ecf57b 100644
--- a/ports/nrf/nrfx_config.h
+++ b/ports/nrf/nrfx_config.h
@@ -47,6 +47,14 @@
   #define GPIO_COUNT 2
 #endif
 
+#if defined(NRF52840)
+// for tinyusb
+//#define NRFX_IRQ_IS_ENABLED 1
+#define NRFX_POWER_ENABLED 1
+#define NRFX_POWER_CONFIG_IRQ_PRIORITY 2
+#define NRFX_SYSTICK_ENABLED 1
+#endif
+
 #define NRFX_GPIOTE_ENABLED 1
 #define NRFX_GPIOTE_CONFIG_NUM_OF_LOW_POWER_EVENTS 1
 #if NRF51
diff --git a/ports/nrf/nrfx_glue.h b/ports/nrf/nrfx_glue.h
index 316e02df1..ffd2cff73 100644
--- a/ports/nrf/nrfx_glue.h
+++ b/ports/nrf/nrfx_glue.h
@@ -138,4 +138,6 @@
 
 #endif // !BLUETOOTH_SD
 
+#define NRFX_IRQ_IS_ENABLED(irq_number) (0 != (NVIC->ISER[irq_number / 32] & (1UL << (irq_number % 32))))
+
 #endif // NRFX_GLUE_H