diff --git a/.gitmodules b/.gitmodules
index 91afffe6a6..5c29c41b9f 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -341,3 +341,7 @@
 [submodule "frozen/Adafruit_CircuitPython_Wave"]
 	path = frozen/Adafruit_CircuitPython_Wave
 	url = http://github.com/adafruit/Adafruit_CircuitPython_Wave.git
+[submodule "ports/raspberrypi/lib/Pico-PIO-USB"]
+	path = ports/raspberrypi/lib/Pico-PIO-USB
+	url = https://github.com/sekigon-gonnoc/Pico-PIO-USB.git
+	branch = main
diff --git a/lib/tinyusb b/lib/tinyusb
index e3b3229d61..f1e006d09b 160000
--- a/lib/tinyusb
+++ b/lib/tinyusb
@@ -1 +1 @@
-Subproject commit e3b3229d61676585879c81d5f2e3393a2a1f1b16
+Subproject commit f1e006d09bd32088ab421d0b519eb89c531eda4e
diff --git a/locale/circuitpython.pot b/locale/circuitpython.pot
index 282d229856..368836a4db 100644
--- a/locale/circuitpython.pot
+++ b/locale/circuitpython.pot
@@ -471,12 +471,17 @@ msgstr ""
 msgid "All channels in use"
 msgstr ""
 
+#: ports/raspberrypi/common-hal/usb_host/Port.c
+msgid "All dma channels in use"
+msgstr ""
+
 #: ports/atmel-samd/common-hal/audioio/AudioOut.c
 msgid "All event channels in use"
 msgstr ""
 
 #: ports/raspberrypi/common-hal/picodvi/Framebuffer.c
 #: ports/raspberrypi/common-hal/rp2pio/StateMachine.c
+#: ports/raspberrypi/common-hal/usb_host/Port.c
 msgid "All state machines in use"
 msgstr ""
 
@@ -1950,10 +1955,6 @@ msgstr ""
 msgid "Size not supported"
 msgstr ""
 
-#: ports/raspberrypi/common-hal/alarm/SleepMemory.c
-msgid "Sleep Memory not available"
-msgstr ""
-
 #: shared-bindings/alarm/SleepMemory.c shared-bindings/memorymap/AddressRange.c
 #: shared-bindings/nvm/ByteArray.c
 msgid "Slice and value different lengths."
diff --git a/ports/mimxrt10xx/Makefile b/ports/mimxrt10xx/Makefile
index c591cf189e..24e3c59b13 100644
--- a/ports/mimxrt10xx/Makefile
+++ b/ports/mimxrt10xx/Makefile
@@ -229,12 +229,19 @@ include $(TOP)/py/mkrules.mk
 print-%:
 	@echo $* = $($*)
 
-ifeq ($(CHIP_FAMILY), MIMXRT1062)
-PYOCD_TARGET = mimxrt1060
-endif
+# Flash using jlink
+define jlink_script
+halt
+loadfile $^
+r
+go
+exit
+endef
+export jlink_script
 
-# Flash using pyocd
-PYOCD_OPTION ?=
-flash: $(BUILD)/firmware.hex
-	pyocd flash -t $(PYOCD_TARGET) $(PYOCD_OPTION) $<
-	pyocd reset -t $(PYOCD_TARGET)
+JLINKEXE = JLinkExe
+flash-jlink: $(BUILD)/firmware.elf
+	@echo "$$jlink_script" > $(BUILD)/firmware.jlink
+	$(JLINKEXE) -device $(CHIP_FAMILY)xxx5A -if swd -JTAGConf -1,-1 -speed auto -CommandFile $(BUILD)/firmware.jlink
+
+flash: flash-jlink
diff --git a/ports/mimxrt10xx/boards/imxrt1060_evk/mpconfigboard.h b/ports/mimxrt10xx/boards/imxrt1060_evk/mpconfigboard.h
index 3b63172328..23058e6952 100644
--- a/ports/mimxrt10xx/boards/imxrt1060_evk/mpconfigboard.h
+++ b/ports/mimxrt10xx/boards/imxrt1060_evk/mpconfigboard.h
@@ -21,5 +21,5 @@
 
 // Put host on the first USB so that right angle OTG adapters can fit. This is
 // the right port when looking at the board.
-#define CIRCUITPY_USB_DEVICE_INSTANCE 1
-#define CIRCUITPY_USB_HOST_INSTANCE 0
+#define CIRCUITPY_USB_DEVICE_INSTANCE 0
+#define CIRCUITPY_USB_HOST_INSTANCE 1
diff --git a/ports/mimxrt10xx/linking/common.ld b/ports/mimxrt10xx/linking/common.ld
index a3ed2dbdbf..71e2c457c3 100644
--- a/ports/mimxrt10xx/linking/common.ld
+++ b/ports/mimxrt10xx/linking/common.ld
@@ -72,6 +72,7 @@ SECTIONS
     *(EXCLUDE_FILE(
         *fsl_flexspi.o
         *dcd_ci_hs.o
+        *ehci.o
         *tusb_fifo.o
         *usbd.o
         *string0.o
@@ -88,6 +89,11 @@ SECTIONS
            We try to only keep USB interrupt related functions. */
         *dcd_ci_hs.o(.text.process_*_request .text.dcd_edpt* .text.dcd_init .text.dcd_set_address)
         *usbd.o(.text.process_*_request .text.process_[gs]et* .text.tud_* .text.usbd_* .text.configuration_reset .text.invoke_*)
+        *ehci.o(.text.hcd_edpt* .text.hcd_setup* .text.ehci_init* .text.hcd_port* .text.hcd_device* .text.qtd_init* .text.list_remove*)
+
+        /* Less critical portions of the runtime. */
+        *runtime.o(.text.mp_import* .text.mp_resume* .text.mp_make_raise*  .text.mp_init)
+        *gc.o(.text.gc_never_free .text.gc_make_long_lived)
 
         /* Anything marked cold/unlikely should be in flash. */
         *(.text.unlikely.*)
@@ -146,6 +152,7 @@ SECTIONS
         *(.itcm.*)
         *fsl_flexspi.o(.text*)
         *dcd_ci_hs.o(.text*)
+        *ehci.o(.text*)
         *tusb_fifo.o(.text*)
         *py/objboundmeth.o(.text*)
         *py/objtype.o(.text*)
diff --git a/ports/raspberrypi/Makefile b/ports/raspberrypi/Makefile
index 7eb67b77ba..f635750415 100644
--- a/ports/raspberrypi/Makefile
+++ b/ports/raspberrypi/Makefile
@@ -148,7 +148,7 @@ INC += \
 CFLAGS += -DRASPBERRYPI -DPICO_ON_DEVICE=1 -DPICO_NO_BINARY_INFO=0 -DPICO_TIME_DEFAULT_ALARM_POOL_DISABLED=0 -DPICO_DIVIDER_CALL_IDIV0=0 -DPICO_DIVIDER_CALL_LDIV0=0 -DPICO_DIVIDER_HARDWARE=1 -DPICO_DOUBLE_ROM=1 -DPICO_FLOAT_ROM=1 -DPICO_MULTICORE=1 -DPICO_BITS_IN_RAM=0 -DPICO_DIVIDER_IN_RAM=0 -DPICO_DOUBLE_PROPAGATE_NANS=0 -DPICO_DOUBLE_IN_RAM=0 -DPICO_MEM_IN_RAM=0 -DPICO_FLOAT_IN_RAM=0 -DPICO_FLOAT_PROPAGATE_NANS=1 -DPICO_NO_FLASH=0 -DPICO_COPY_TO_RAM=0 -DPICO_DISABLE_SHARED_IRQ_HANDLERS=0 -DPICO_NO_BI_BOOTSEL_VIA_DOUBLE_RESET=0 -DDVI_1BPP_BIT_REVERSE=0
 OPTIMIZATION_FLAGS ?= -O3
 # TinyUSB defines
-CFLAGS += -DTUD_OPT_RP2040_USB_DEVICE_ENUMERATION_FIX=1 -DCFG_TUSB_MCU=OPT_MCU_RP2040 -DCFG_TUD_MIDI_RX_BUFSIZE=128 -DCFG_TUD_CDC_RX_BUFSIZE=256 -DCFG_TUD_MIDI_TX_BUFSIZE=128 -DCFG_TUD_CDC_TX_BUFSIZE=256 -DCFG_TUD_MSC_BUFSIZE=1024
+CFLAGS += -DCFG_TUSB_OS=OPT_OS_PICO -DTUD_OPT_RP2040_USB_DEVICE_ENUMERATION_FIX=1 -DCFG_TUSB_MCU=OPT_MCU_RP2040 -DCFG_TUD_MIDI_RX_BUFSIZE=128 -DCFG_TUD_CDC_RX_BUFSIZE=256 -DCFG_TUD_MIDI_TX_BUFSIZE=128 -DCFG_TUD_CDC_TX_BUFSIZE=256 -DCFG_TUD_MSC_BUFSIZE=1024
 
 # option to override default optimization level, set in boards/$(BOARD)/mpconfigboard.mk
 CFLAGS += $(OPTIMIZATION_FLAGS)
@@ -258,6 +258,18 @@ SRC_C += \
 	$(SRC_CYW43) \
 	$(SRC_LWIP) \
 
+
+ifeq ($(CIRCUITPY_USB_HOST), 1)
+SRC_C += \
+  lib/tinyusb/src/portable/raspberrypi/pio_usb/hcd_pio_usb.c \
+  lib/Pico-PIO-USB/src/pio_usb.c \
+  lib/Pico-PIO-USB/src/pio_usb_host.c \
+  lib/Pico-PIO-USB/src/usb_crc.c \
+
+INC += \
+  -isystem lib/Pico-PIO-USB/src
+endif
+
 ifeq ($(CIRCUITPY_PICODVI),1)
 SRC_C += \
   bindings/picodvi/__init__.c \
diff --git a/ports/raspberrypi/boards/adafruit_feather_rp2040_usb_host/board.c b/ports/raspberrypi/boards/adafruit_feather_rp2040_usb_host/board.c
index 331653173e..724fde1d27 100644
--- a/ports/raspberrypi/boards/adafruit_feather_rp2040_usb_host/board.c
+++ b/ports/raspberrypi/boards/adafruit_feather_rp2040_usb_host/board.c
@@ -26,4 +26,18 @@
 
 #include "supervisor/board.h"
 
+#include "shared-bindings/digitalio/DigitalInOut.h"
+#include "shared-bindings/usb_host/Port.h"
+
 // Use the MP_WEAK supervisor/shared/board.c versions of routines not defined here.
+
+usb_host_port_obj_t _host_port;
+digitalio_digitalinout_obj_t _host_power;
+
+void board_init(void) {
+    common_hal_digitalio_digitalinout_construct(&_host_power, &pin_GPIO18);
+    common_hal_digitalio_digitalinout_never_reset(&_host_power);
+    common_hal_digitalio_digitalinout_switch_to_output(&_host_power, true, DRIVE_MODE_PUSH_PULL);
+
+    common_hal_usb_host_port_construct(&_host_port, &pin_GPIO16, &pin_GPIO17);
+}
diff --git a/ports/raspberrypi/boards/adafruit_feather_rp2040_usb_host/mpconfigboard.h b/ports/raspberrypi/boards/adafruit_feather_rp2040_usb_host/mpconfigboard.h
index f300bfe711..ba62bca2cb 100644
--- a/ports/raspberrypi/boards/adafruit_feather_rp2040_usb_host/mpconfigboard.h
+++ b/ports/raspberrypi/boards/adafruit_feather_rp2040_usb_host/mpconfigboard.h
@@ -12,3 +12,8 @@
 
 #define DEFAULT_UART_BUS_RX (&pin_GPIO1)
 #define DEFAULT_UART_BUS_TX (&pin_GPIO0)
+
+#define CIRCUITPY_CONSOLE_UART_RX DEFAULT_UART_BUS_RX
+#define CIRCUITPY_CONSOLE_UART_TX DEFAULT_UART_BUS_TX
+
+#define CIRCUITPY_USB_HOST_INSTANCE 1
diff --git a/ports/raspberrypi/common-hal/rp2pio/StateMachine.h b/ports/raspberrypi/common-hal/rp2pio/StateMachine.h
index 71f85b1f11..f2d642bbad 100644
--- a/ports/raspberrypi/common-hal/rp2pio/StateMachine.h
+++ b/ports/raspberrypi/common-hal/rp2pio/StateMachine.h
@@ -98,6 +98,8 @@ void rp2pio_statemachine_dma_complete(rp2pio_statemachine_obj_t *self, int chann
 void rp2pio_statemachine_reset_ok(PIO pio, int sm);
 void rp2pio_statemachine_never_reset(PIO pio, int sm);
 
+uint8_t rp2pio_statemachine_find_pio(int program_size, int sm_count);
+
 extern const mp_obj_type_t rp2pio_statemachine_type;
 
 #endif // MICROPY_INCLUDED_RASPBERRYPI_COMMON_HAL_RP2PIO_STATEMACHINE_H
diff --git a/ports/raspberrypi/common-hal/usb_host/Port.c b/ports/raspberrypi/common-hal/usb_host/Port.c
new file mode 100644
index 0000000000..9ad28c73ea
--- /dev/null
+++ b/ports/raspberrypi/common-hal/usb_host/Port.c
@@ -0,0 +1,165 @@
+/*
+ * This file is part of the Micro Python project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2022 Scott Shawcroft for Adafruit Industries
+ *
+ * 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 "bindings/rp2pio/StateMachine.h"
+#include "shared-bindings/microcontroller/Pin.h"
+#include "shared-bindings/microcontroller/Processor.h"
+#include "shared-bindings/usb_host/Port.h"
+#include "supervisor/usb.h"
+
+#include "src/common/pico_time/include/pico/time.h"
+#include "src/rp2040/hardware_structs/include/hardware/structs/mpu.h"
+#include "src/rp2_common/cmsis/stub/CMSIS/Device/RaspberryPi/RP2040/Include/RP2040.h"
+#include "src/rp2_common/hardware_dma/include/hardware/dma.h"
+#include "src/rp2_common/pico_multicore/include/pico/multicore.h"
+
+#include "py/runtime.h"
+
+#include "tusb.h"
+
+#include "lib/Pico-PIO-USB/src/pio_usb.h"
+#include "lib/Pico-PIO-USB/src/pio_usb_configuration.h"
+
+#include "supervisor/serial.h"
+
+bool usb_host_init;
+
+STATIC PIO pio_instances[2] = {pio0, pio1};
+volatile bool _core1_ready = false;
+
+static void __not_in_flash_func(core1_main)(void) {
+    // The MPU is reset before this starts.
+    SysTick->LOAD = (uint32_t)((common_hal_mcu_processor_get_frequency() / 1000) - 1UL);
+    SysTick->VAL = 0UL;   /* Load the SysTick Counter Value */
+    SysTick->CTRL = SysTick_CTRL_CLKSOURCE_Msk |  // Processor clock.
+        SysTick_CTRL_ENABLE_Msk;
+
+    // Turn off flash access. After this, it will hard fault. Better than messing
+    // up CIRCUITPY.
+    MPU->CTRL = MPU_CTRL_PRIVDEFENA_Msk | MPU_CTRL_ENABLE_Msk;
+    MPU->RNR = 6; // 7 is used by pico-sdk stack protection.
+    MPU->RBAR = XIP_MAIN_BASE | MPU_RBAR_VALID_Msk;
+    MPU->RASR = MPU_RASR_XN_Msk | // Set execute never and everything else is restricted.
+        MPU_RASR_ENABLE_Msk |
+        (0x1b << MPU_RASR_SIZE_Pos);         // Size is 0x10000000 which masks up to SRAM region.
+    MPU->RNR = 7;
+
+    _core1_ready = true;
+
+    while (true) {
+        pio_usb_host_frame();
+        if (tuh_task_event_ready()) {
+            // Queue the tinyusb background task.
+            usb_background_schedule();
+        }
+        // Wait for systick to reload.
+        while ((SysTick->CTRL & SysTick_CTRL_COUNTFLAG_Msk) == 0) {
+        }
+    }
+}
+
+STATIC uint8_t _sm_free_count(uint8_t pio_index) {
+    PIO pio = pio_instances[pio_index];
+    uint8_t free_count = 0;
+    for (size_t j = 0; j < NUM_PIO_STATE_MACHINES; j++) {
+        if (!pio_sm_is_claimed(pio, j)) {
+            free_count++;
+        }
+    }
+    return free_count;
+}
+
+STATIC bool _has_program_room(uint8_t pio_index, uint8_t program_size) {
+    PIO pio = pio_instances[pio_index];
+    pio_program_t program_struct = {
+        .instructions = NULL,
+        .length = program_size,
+        .origin = -1
+    };
+    return pio_can_add_program(pio, &program_struct);
+}
+
+void common_hal_usb_host_port_construct(usb_host_port_obj_t *self, const mcu_pin_obj_t *dp, const mcu_pin_obj_t *dm) {
+    if (dp->number + 1 != dm->number) {
+        raise_ValueError_invalid_pins();
+    }
+    pio_usb_configuration_t pio_cfg = PIO_USB_DEFAULT_CONFIG;
+    pio_cfg.skip_alarm_pool = true;
+    pio_cfg.pin_dp = dp->number;
+    pio_cfg.pio_tx_num = 0;
+    pio_cfg.pio_rx_num = 1;
+    // PIO with room for 22 instructions
+    // PIO with room for 31 instructions and two free SM.
+    if (!_has_program_room(pio_cfg.pio_tx_num, 22) || _sm_free_count(pio_cfg.pio_tx_num) < 1 ||
+        !_has_program_room(pio_cfg.pio_rx_num, 31) || _sm_free_count(pio_cfg.pio_rx_num) < 2) {
+        mp_raise_RuntimeError(translate("All state machines in use"));
+    }
+    pio_cfg.tx_ch = dma_claim_unused_channel(false); // DMA channel
+    if (pio_cfg.tx_ch < 0) {
+        mp_raise_RuntimeError(translate("All dma channels in use"));
+    }
+
+    PIO tx_pio = pio_instances[pio_cfg.pio_tx_num];
+    pio_cfg.sm_tx = pio_claim_unused_sm(tx_pio, false);
+    PIO rx_pio = pio_instances[pio_cfg.pio_rx_num];
+    pio_cfg.sm_rx = pio_claim_unused_sm(rx_pio, false);
+    pio_cfg.sm_eop = pio_claim_unused_sm(rx_pio, false);
+
+    // Unclaim everything so that the library can.
+    dma_channel_unclaim(pio_cfg.tx_ch);
+    pio_sm_unclaim(tx_pio, pio_cfg.sm_tx);
+    pio_sm_unclaim(rx_pio, pio_cfg.sm_rx);
+    pio_sm_unclaim(rx_pio, pio_cfg.sm_eop);
+
+    // Set all of the state machines to never reset.
+    rp2pio_statemachine_never_reset(tx_pio, pio_cfg.sm_tx);
+    rp2pio_statemachine_never_reset(rx_pio, pio_cfg.sm_rx);
+    rp2pio_statemachine_never_reset(rx_pio, pio_cfg.sm_eop);
+
+    common_hal_never_reset_pin(dp);
+    common_hal_never_reset_pin(dm);
+
+    // Core 1 will run the SOF interrupt directly.
+    _core1_ready = false;
+    multicore_launch_core1(core1_main);
+    while (!_core1_ready) {
+    }
+
+    tuh_configure(TUH_OPT_RHPORT, TUH_CFGID_RPI_PIO_USB_CONFIGURATION, &pio_cfg);
+    tuh_init(TUH_OPT_RHPORT);
+
+    self->init = true;
+    usb_host_init = true;
+}
+
+void common_hal_usb_host_port_deinit(usb_host_port_obj_t *self) {
+    self->init = false;
+    usb_host_init = false;
+}
+
+bool common_hal_usb_host_port_deinited(usb_host_port_obj_t *self) {
+    return !self->init;
+}
diff --git a/ports/raspberrypi/common-hal/usb_host/Port.h b/ports/raspberrypi/common-hal/usb_host/Port.h
new file mode 100644
index 0000000000..c9294debb2
--- /dev/null
+++ b/ports/raspberrypi/common-hal/usb_host/Port.h
@@ -0,0 +1,38 @@
+/*
+ * This file is part of the Micro Python project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2023 Scott Shawcroft for Adafruit Industries
+ *
+ * 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.
+ */
+
+#pragma once
+
+#include "py/obj.h"
+
+typedef struct {
+    mp_obj_base_t base;
+    bool init;
+} usb_host_port_obj_t;
+
+// Cheater state so that the usb module knows if it should return the TinyUSB
+// state.
+extern bool usb_host_init;
diff --git a/ports/raspberrypi/common-hal/usb_host/__init__.c b/ports/raspberrypi/common-hal/usb_host/__init__.c
new file mode 100644
index 0000000000..3b54bd6a5d
--- /dev/null
+++ b/ports/raspberrypi/common-hal/usb_host/__init__.c
@@ -0,0 +1,27 @@
+/*
+ * This file is part of the Micro Python project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2022 Scott Shawcroft for Adafruit Industries
+ *
+ * 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.
+ */
+
+// Nothing
diff --git a/ports/raspberrypi/lib/Pico-PIO-USB b/ports/raspberrypi/lib/Pico-PIO-USB
new file mode 160000
index 0000000000..5a7aa8d4e7
--- /dev/null
+++ b/ports/raspberrypi/lib/Pico-PIO-USB
@@ -0,0 +1 @@
+Subproject commit 5a7aa8d4e78f9a50e4fb9defcf3488b3fc44aff1
diff --git a/ports/raspberrypi/link.ld b/ports/raspberrypi/link.ld
index 1e758f61bf..0e584c94ac 100644
--- a/ports/raspberrypi/link.ld
+++ b/ports/raspberrypi/link.ld
@@ -80,7 +80,9 @@ SECTIONS
         *(.property_getset)
         __property_getset_end = .;
 
-        *(EXCLUDE_FILE(*libgcc.a: *libc.a:*lib_a-mem*.o *libm.a: *interp.o *divider.o) .text*)
+        *(EXCLUDE_FILE(*libgcc.a: *libc.a:*lib_a-mem*.o *libm.a: *interp.o *divider.o *tusb_fifo.o *mem_ops_aeabi.o *usbh.o) .text*)
+        /* Allow everything in usbh.o except tuh_task_event_ready because we read it from core 1. */
+        *usbh.o (.text.[_uphc]* .text.tuh_[cmvied]* .text.tuh_task_ext*)
         *(.fini)
         /* Pull all c'tors into .text */
         *crtbegin.o(.ctors)
@@ -169,7 +171,7 @@ SECTIONS
         . = ALIGN(4);
         /* init data */
         PROVIDE_HIDDEN (__init_array_start = .);
-        KEEP(*(SORT(.init_array.*)))
+        KEEP(*(SORT(.init_array*)))
         KEEP(*(.init_array))
         PROVIDE_HIDDEN (__init_array_end = .);
 
@@ -248,6 +250,7 @@ SECTIONS
         __scratch_x_start__ = .;
         *(.scratch_x.*)
         *tmds_encode.o (.time_critical*)
+        *timer.o (.text.hardware_alarm_irq_handler)
         . = ALIGN(4);
         __scratch_x_end__ = .;
     } > SCRATCH_X AT > FLASH_FIRMWARE
diff --git a/ports/raspberrypi/mpconfigport.h b/ports/raspberrypi/mpconfigport.h
index a2eb9a15ef..4458107974 100644
--- a/ports/raspberrypi/mpconfigport.h
+++ b/ports/raspberrypi/mpconfigport.h
@@ -48,6 +48,10 @@
 
 #define CIRCUITPY_PROCESSOR_COUNT           (2)
 
+#if CIRCUITPY_USB_HOST
+#define CIRCUITPY_USB_HOST_INSTANCE 1
+#endif
+
 // This also includes mpconfigboard.h.
 #include "py/circuitpy_mpconfig.h"
 
@@ -64,4 +68,11 @@
 #define MICROPY_PY_LWIP_EXIT    cyw43_arch_lwip_end();
 #endif
 
+// Protect the background queue with a lock because both cores may modify it.
+#include "pico/critical_section.h"
+extern critical_section_t background_queue_lock;
+#define CALLBACK_CRITICAL_BEGIN (critical_section_enter_blocking(&background_queue_lock))
+#define CALLBACK_CRITICAL_END (critical_section_exit(&background_queue_lock))
+
+
 #endif  // __INCLUDED_MPCONFIGPORT_H
diff --git a/ports/raspberrypi/mpconfigport.mk b/ports/raspberrypi/mpconfigport.mk
index cdee964410..fdc2b0922a 100644
--- a/ports/raspberrypi/mpconfigport.mk
+++ b/ports/raspberrypi/mpconfigport.mk
@@ -20,6 +20,7 @@ CIRCUITPY_RGBMATRIX ?= $(CIRCUITPY_DISPLAYIO)
 CIRCUITPY_ROTARYIO ?= 1
 CIRCUITPY_ROTARYIO_SOFTENCODER = 1
 CIRCUITPY_SYNTHIO_MAX_CHANNELS = 12
+CIRCUITPY_USB_HOST ?= 1
 
 # Things that need to be implemented.
 # Use PWM internally
diff --git a/ports/raspberrypi/supervisor/port.c b/ports/raspberrypi/supervisor/port.c
index 08a9d96c2e..9415d36aa6 100644
--- a/ports/raspberrypi/supervisor/port.c
+++ b/ports/raspberrypi/supervisor/port.c
@@ -76,6 +76,8 @@
 #include "tusb.h"
 #include <cmsis_compiler.h>
 
+critical_section_t background_queue_lock;
+
 extern volatile bool mp_msc_enabled;
 
 STATIC void _tick_callback(uint alarm_num);
@@ -128,6 +130,9 @@ safe_mode_t port_init(void) {
         (&_ld_dtcm_bss_start)[i] = 0;
     }
 
+    // Set up the critical section to protect the background task queue.
+    critical_section_init(&background_queue_lock);
+
     #if CIRCUITPY_CYW43
     never_reset_pin_number(23);
     never_reset_pin_number(24);
@@ -299,7 +304,7 @@ void port_interrupt_after_ticks(uint32_t ticks) {
 
 void port_idle_until_interrupt(void) {
     common_hal_mcu_disable_interrupts();
-    if (!background_callback_pending() && !tud_task_event_ready() && !_woken_up) {
+    if (!background_callback_pending() && !tud_task_event_ready() && !tuh_task_event_ready() && !_woken_up) {
         __DSB();
         __WFI();
     }
diff --git a/py/circuitpy_mpconfig.mk b/py/circuitpy_mpconfig.mk
index 3e43909687..210c402c77 100644
--- a/py/circuitpy_mpconfig.mk
+++ b/py/circuitpy_mpconfig.mk
@@ -525,6 +525,9 @@ CFLAGS += -DCIRCUITPY_USB_HOST=$(CIRCUITPY_USB_HOST)
 CIRCUITPY_USB_IDENTIFICATION ?= $(CIRCUITPY_USB)
 CFLAGS += -DCIRCUITPY_USB_IDENTIFICATION=$(CIRCUITPY_USB_IDENTIFICATION)
 
+CIRCUITPY_USB_KEYBOARD_WORKFLOW ?= $(CIRCUITPY_USB_HOST)
+CFLAGS += -DCIRCUITPY_USB_KEYBOARD_WORKFLOW=$(CIRCUITPY_USB_KEYBOARD_WORKFLOW)
+
 # MIDI is available by default, but is not turned on if there are fewer than 8 endpoints.
 CIRCUITPY_USB_MIDI ?= $(CIRCUITPY_USB)
 CFLAGS += -DCIRCUITPY_USB_MIDI=$(CIRCUITPY_USB_MIDI)
diff --git a/shared-bindings/usb/core/Device.c b/shared-bindings/usb/core/Device.c
index 40bb01dc08..d5525431a3 100644
--- a/shared-bindings/usb/core/Device.c
+++ b/shared-bindings/usb/core/Device.c
@@ -123,6 +123,30 @@ MP_DEFINE_CONST_FUN_OBJ_1(usb_core_device_get_manufacturer_obj, usb_core_device_
 MP_PROPERTY_GETTER(usb_core_device_manufacturer_obj,
     (mp_obj_t)&usb_core_device_get_manufacturer_obj);
 
+//|     def set_configuration(self, configuration=None):
+//|         """Set the active configuration.
+//|
+//|         The configuration parameter is the bConfigurationValue field of the
+//|         configuration you want to set as active. If you call this method
+//|         without parameter, it will use the first configuration found.  As a
+//|         device hardly ever has more than one configuration, calling the method
+//|         without arguments is enough to get the device ready.
+//|         """
+//|         ...
+STATIC mp_obj_t usb_core_device_set_configuration(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
+    enum { ARG_configuration };
+    static const mp_arg_t allowed_args[] = {
+        { MP_QSTR_configuration, MP_ARG_INT, {.u_int = 0x100} },
+    };
+    usb_core_device_obj_t *self = MP_OBJ_TO_PTR(pos_args[0]);
+    mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
+    mp_arg_parse_all(n_args - 1, pos_args + 1, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
+
+    common_hal_usb_core_device_set_configuration(self, args[ARG_configuration].u_int);
+    return mp_const_none;
+}
+MP_DEFINE_CONST_FUN_OBJ_KW(usb_core_device_set_configuration_obj, 1, usb_core_device_set_configuration);
+
 //|     def write(self, endpoint: int, data: ReadableBuffer, timeout: Optional[int] = None) -> int:
 //|         """Write data to a specific endpoint on the device.
 //|
@@ -223,7 +247,10 @@ STATIC mp_obj_t usb_core_device_ctrl_transfer(size_t n_args, const mp_obj_t *pos
 
     mp_buffer_info_t bufinfo;
     // check request type
-    if ((args[ARG_bmRequestType].u_int & 0x80) != 0) {
+    if (args[ARG_data_or_wLength].u_obj == mp_const_none) {
+        bufinfo.len = 0;
+        bufinfo.buf = NULL;
+    } else if ((args[ARG_bmRequestType].u_int & 0x80) != 0) {
         mp_get_buffer_raise(args[ARG_data_or_wLength].u_obj, &bufinfo, MP_BUFFER_WRITE);
     } else {
         mp_get_buffer_raise(args[ARG_data_or_wLength].u_obj, &bufinfo, MP_BUFFER_READ);
@@ -292,6 +319,7 @@ STATIC const mp_rom_map_elem_t usb_core_device_locals_dict_table[] = {
     { MP_ROM_QSTR(MP_QSTR_product),          MP_ROM_PTR(&usb_core_device_product_obj) },
     { MP_ROM_QSTR(MP_QSTR_manufacturer),     MP_ROM_PTR(&usb_core_device_manufacturer_obj) },
 
+    { MP_ROM_QSTR(MP_QSTR_set_configuration),MP_ROM_PTR(&usb_core_device_set_configuration_obj) },
     { MP_ROM_QSTR(MP_QSTR_write),            MP_ROM_PTR(&usb_core_device_write_obj) },
     { MP_ROM_QSTR(MP_QSTR_read),             MP_ROM_PTR(&usb_core_device_read_obj) },
     { MP_ROM_QSTR(MP_QSTR_ctrl_transfer),    MP_ROM_PTR(&usb_core_device_ctrl_transfer_obj) },
diff --git a/shared-bindings/usb/core/Device.h b/shared-bindings/usb/core/Device.h
index c7086e99ff..c9de5d505f 100644
--- a/shared-bindings/usb/core/Device.h
+++ b/shared-bindings/usb/core/Device.h
@@ -39,8 +39,9 @@ uint16_t common_hal_usb_core_device_get_idProduct(usb_core_device_obj_t *self);
 mp_obj_t common_hal_usb_core_device_get_serial_number(usb_core_device_obj_t *self);
 mp_obj_t common_hal_usb_core_device_get_product(usb_core_device_obj_t *self);
 mp_obj_t common_hal_usb_core_device_get_manufacturer(usb_core_device_obj_t *self);
-mp_obj_t common_hal_usb_core_device_write(usb_core_device_obj_t *self, mp_int_t endpoint, const uint8_t *buffer, mp_int_t len, mp_int_t timeout);
-mp_obj_t common_hal_usb_core_device_read(usb_core_device_obj_t *self, mp_int_t endpoint, uint8_t *buffer, mp_int_t len, mp_int_t timeout);
+void common_hal_usb_core_device_set_configuration(usb_core_device_obj_t *self, mp_int_t configuration);
+mp_int_t common_hal_usb_core_device_write(usb_core_device_obj_t *self, mp_int_t endpoint, const uint8_t *buffer, mp_int_t len, mp_int_t timeout);
+mp_int_t common_hal_usb_core_device_read(usb_core_device_obj_t *self, mp_int_t endpoint, uint8_t *buffer, mp_int_t len, mp_int_t timeout);
 mp_int_t common_hal_usb_core_device_ctrl_transfer(usb_core_device_obj_t *self,
     mp_int_t bmRequestType, mp_int_t bRequest,
     mp_int_t wValue, mp_int_t wIndex,
diff --git a/shared-bindings/usb/core/__init__.c b/shared-bindings/usb/core/__init__.c
index faeef23a88..7c171e85d6 100644
--- a/shared-bindings/usb/core/__init__.c
+++ b/shared-bindings/usb/core/__init__.c
@@ -49,10 +49,15 @@
 //|
 MP_DEFINE_USB_CORE_EXCEPTION(USBError, OSError)
 NORETURN void mp_raise_usb_core_USBError(const compressed_string_t *fmt, ...) {
-    va_list argptr;
-    va_start(argptr,fmt);
-    mp_obj_t exception = mp_obj_new_exception_msg_vlist(&mp_type_usb_core_USBError, fmt, argptr);
-    va_end(argptr);
+    mp_obj_t exception;
+    if (fmt == NULL) {
+        exception = mp_obj_new_exception(&mp_type_usb_core_USBError);
+    } else {
+        va_list argptr;
+        va_start(argptr,fmt);
+        exception = mp_obj_new_exception_msg_vlist(&mp_type_usb_core_USBError, fmt, argptr);
+        va_end(argptr);
+    }
     nlr_raise(exception);
 }
 
diff --git a/shared-module/usb/core/Device.c b/shared-module/usb/core/Device.c
index 706c94eec3..67756341ec 100644
--- a/shared-module/usb/core/Device.c
+++ b/shared-module/usb/core/Device.c
@@ -34,15 +34,30 @@
 #include "shared-bindings/usb/core/__init__.h"
 #include "shared-module/usb/utf16le.h"
 #include "supervisor/shared/tick.h"
+#include "supervisor/usb.h"
 
+// Track what device numbers are mounted. We can't use tuh_ready() because it is
+// true before enumeration completes and TinyUSB drivers are started.
+STATIC size_t _mounted_devices = 0;
+
+void tuh_mount_cb(uint8_t dev_addr) {
+    _mounted_devices |= 1 << dev_addr;
+}
+
+void tuh_umount_cb(uint8_t dev_addr) {
+    _mounted_devices &= ~(1 << dev_addr);
+}
+
+STATIC xfer_result_t _xfer_result;
 bool common_hal_usb_core_device_construct(usb_core_device_obj_t *self, uint8_t device_number) {
     if (device_number == 0 || device_number > CFG_TUH_DEVICE_MAX + CFG_TUH_HUB) {
         return false;
     }
-    if (!tuh_ready(device_number)) {
+    if ((_mounted_devices & (1 << device_number)) == 0) {
         return false;
     }
     self->device_number = device_number;
+    _xfer_result = 0xff;
     return true;
 }
 
@@ -60,19 +75,21 @@ uint16_t common_hal_usb_core_device_get_idProduct(usb_core_device_obj_t *self) {
     return pid;
 }
 
-STATIC xfer_result_t _get_string_result;
 STATIC void _transfer_done_cb(tuh_xfer_t *xfer) {
     // Store the result so we stop waiting for the transfer.
-    _get_string_result = xfer->result;
+    _xfer_result = xfer->result;
 }
 
-STATIC void _wait_for_callback(void) {
+STATIC bool _wait_for_callback(void) {
     while (!mp_hal_is_interrupted() &&
-           _get_string_result == 0xff) {
+           _xfer_result == 0xff) {
         // The background tasks include TinyUSB which will call the function
         // we provided above. In other words, the callback isn't in an interrupt.
         RUN_BACKGROUND_TASKS;
     }
+    xfer_result_t result = _xfer_result;
+    _xfer_result = 0xff;
+    return result == XFER_RESULT_SUCCESS;
 }
 
 STATIC mp_obj_t _get_string(const uint16_t *temp_buf) {
@@ -84,46 +101,145 @@ STATIC mp_obj_t _get_string(const uint16_t *temp_buf) {
 }
 
 mp_obj_t common_hal_usb_core_device_get_serial_number(usb_core_device_obj_t *self) {
-    _get_string_result = 0xff;
     uint16_t temp_buf[127];
-    if (!tuh_descriptor_get_serial_string(self->device_number, 0, temp_buf, MP_ARRAY_SIZE(temp_buf), _transfer_done_cb, 0)) {
+    if (!tuh_descriptor_get_serial_string(self->device_number, 0, temp_buf, MP_ARRAY_SIZE(temp_buf), _transfer_done_cb, 0) ||
+        !_wait_for_callback()) {
         return mp_const_none;
     }
-    _wait_for_callback();
     return _get_string(temp_buf);
 }
 
 mp_obj_t common_hal_usb_core_device_get_product(usb_core_device_obj_t *self) {
-    _get_string_result = 0xff;
     uint16_t temp_buf[127];
-    if (!tuh_descriptor_get_product_string(self->device_number, 0, temp_buf, MP_ARRAY_SIZE(temp_buf), _transfer_done_cb, 0)) {
+    if (!tuh_descriptor_get_product_string(self->device_number, 0, temp_buf, MP_ARRAY_SIZE(temp_buf), _transfer_done_cb, 0) ||
+        !_wait_for_callback()) {
         return mp_const_none;
     }
-    _wait_for_callback();
     return _get_string(temp_buf);
 }
 
 mp_obj_t common_hal_usb_core_device_get_manufacturer(usb_core_device_obj_t *self) {
-    _get_string_result = 0xff;
     uint16_t temp_buf[127];
-    if (!tuh_descriptor_get_manufacturer_string(self->device_number, 0, temp_buf, MP_ARRAY_SIZE(temp_buf), _transfer_done_cb, 0)) {
+    if (!tuh_descriptor_get_manufacturer_string(self->device_number, 0, temp_buf, MP_ARRAY_SIZE(temp_buf), _transfer_done_cb, 0) ||
+        !_wait_for_callback()) {
         return mp_const_none;
     }
-    _wait_for_callback();
     return _get_string(temp_buf);
 }
 
-mp_obj_t common_hal_usb_core_device_write(usb_core_device_obj_t *self, mp_int_t endpoint, const uint8_t *buffer, mp_int_t len, mp_int_t timeout) {
-    return mp_const_none;
+void common_hal_usb_core_device_set_configuration(usb_core_device_obj_t *self, mp_int_t configuration) {
+    if (configuration == 0x100) {
+        tusb_desc_configuration_t desc;
+        if (!tuh_descriptor_get_configuration(self->device_number, 0, &desc, sizeof(desc), _transfer_done_cb, 0) ||
+            !_wait_for_callback()) {
+            return;
+        }
+        configuration = desc.bConfigurationValue;
+    }
+    tuh_configuration_set(self->device_number, configuration, _transfer_done_cb, 0);
+    _wait_for_callback();
 }
 
-mp_obj_t common_hal_usb_core_device_read(usb_core_device_obj_t *self, mp_int_t endpoint, uint8_t *buffer, mp_int_t len, mp_int_t timeout) {
-    return mp_const_none;
+STATIC size_t _xfer(tuh_xfer_t *xfer, mp_int_t timeout) {
+    _xfer_result = 0xff;
+    xfer->complete_cb = _transfer_done_cb;
+    if (!tuh_edpt_xfer(xfer)) {
+        mp_raise_usb_core_USBError(NULL);
+    }
+    uint32_t start_time = supervisor_ticks_ms32();
+    while ((timeout == 0 || supervisor_ticks_ms32() - start_time < (uint32_t)timeout) &&
+           !mp_hal_is_interrupted() &&
+           _xfer_result == 0xff) {
+        // The background tasks include TinyUSB which will call the function
+        // we provided above. In other words, the callback isn't in an interrupt.
+        RUN_BACKGROUND_TASKS;
+    }
+    if (mp_hal_is_interrupted()) {
+        return 0;
+    }
+    xfer_result_t result = _xfer_result;
+    _xfer_result = 0xff;
+    if (result == XFER_RESULT_STALLED || result == 0xff) {
+        mp_raise_usb_core_USBTimeoutError();
+    }
+    if (result == XFER_RESULT_SUCCESS) {
+        return xfer->actual_len;
+    }
+
+    return 0;
 }
 
-xfer_result_t control_result;
-STATIC void _control_complete_cb(tuh_xfer_t *xfer) {
-    control_result = xfer->result;
+STATIC bool _open_endpoint(usb_core_device_obj_t *self, mp_int_t endpoint) {
+    bool endpoint_open = false;
+    size_t open_size = sizeof(self->open_endpoints);
+    size_t first_free = open_size;
+    for (size_t i = 0; i < open_size; i++) {
+        if (self->open_endpoints[i] == endpoint) {
+            endpoint_open = true;
+        } else if (first_free == open_size && self->open_endpoints[i] == 0) {
+            first_free = i;
+        }
+    }
+    if (endpoint_open) {
+        return true;
+    }
+
+    // Fetch the full configuration descriptor and search for the endpoint's descriptor.
+    uint8_t desc_buf[128];
+    if (!tuh_descriptor_get_configuration(self->device_number, self->configuration_index, &desc_buf, sizeof(desc_buf), _transfer_done_cb, 0) ||
+        !_wait_for_callback()) {
+        return false;
+    }
+    tusb_desc_configuration_t *desc_cfg = (tusb_desc_configuration_t *)desc_buf;
+
+    uint8_t const *desc_end = ((uint8_t const *)desc_cfg) + tu_le16toh(desc_cfg->wTotalLength);
+    uint8_t const *p_desc = tu_desc_next(desc_cfg);
+
+    // parse each interfaces
+    while (p_desc < desc_end) {
+        if (TUSB_DESC_ENDPOINT == tu_desc_type(p_desc)) {
+            tusb_desc_endpoint_t const *desc_ep = (tusb_desc_endpoint_t const *)p_desc;
+            if (desc_ep->bEndpointAddress == endpoint) {
+                break;
+            }
+        }
+
+        p_desc = tu_desc_next(p_desc);
+    }
+    if (p_desc >= desc_end) {
+        return false;
+    }
+    tusb_desc_endpoint_t const *desc_ep = (tusb_desc_endpoint_t const *)p_desc;
+
+    bool open = tuh_edpt_open(self->device_number, desc_ep);
+    if (open) {
+        self->open_endpoints[first_free] = endpoint;
+    }
+    return open;
+}
+
+mp_int_t common_hal_usb_core_device_write(usb_core_device_obj_t *self, mp_int_t endpoint, const uint8_t *buffer, mp_int_t len, mp_int_t timeout) {
+    if (!_open_endpoint(self, endpoint)) {
+        mp_raise_usb_core_USBError(NULL);
+    }
+    tuh_xfer_t xfer;
+    xfer.daddr = self->device_number;
+    xfer.ep_addr = endpoint;
+    xfer.buffer = (uint8_t *)buffer;
+    xfer.buflen = len;
+    return _xfer(&xfer, timeout);
+}
+
+mp_int_t common_hal_usb_core_device_read(usb_core_device_obj_t *self, mp_int_t endpoint, uint8_t *buffer, mp_int_t len, mp_int_t timeout) {
+    if (!_open_endpoint(self, endpoint)) {
+        mp_raise_usb_core_USBError(NULL);
+    }
+    tuh_xfer_t xfer;
+    xfer.daddr = self->device_number;
+    xfer.ep_addr = endpoint;
+    xfer.buffer = buffer;
+    xfer.buflen = len;
+    return _xfer(&xfer, timeout);
 }
 
 mp_int_t common_hal_usb_core_device_ctrl_transfer(usb_core_device_obj_t *self,
@@ -144,27 +260,31 @@ mp_int_t common_hal_usb_core_device_ctrl_transfer(usb_core_device_obj_t *self,
         .ep_addr = 0,
         .setup = &request,
         .buffer = buffer,
-        .complete_cb = _control_complete_cb,
+        .complete_cb = _transfer_done_cb,
     };
 
-    control_result = XFER_RESULT_STALLED;
+    _xfer_result = 0xff;
 
-    bool result = tuh_control_xfer(&xfer);
-    if (!result) {
+    if (!tuh_control_xfer(&xfer)) {
         mp_raise_usb_core_USBError(NULL);
     }
     uint32_t start_time = supervisor_ticks_ms32();
-    while (supervisor_ticks_ms32() - start_time < (uint32_t)timeout &&
+    while ((timeout == 0 || supervisor_ticks_ms32() - start_time < (uint32_t)timeout) &&
            !mp_hal_is_interrupted() &&
-           control_result == XFER_RESULT_STALLED) {
+           _xfer_result == 0xff) {
         // The background tasks include TinyUSB which will call the function
         // we provided above. In other words, the callback isn't in an interrupt.
         RUN_BACKGROUND_TASKS;
     }
-    if (control_result == XFER_RESULT_STALLED) {
+    if (mp_hal_is_interrupted()) {
+        return 0;
+    }
+    xfer_result_t result = _xfer_result;
+    _xfer_result = 0xff;
+    if (result == XFER_RESULT_STALLED || result == 0xff) {
         mp_raise_usb_core_USBTimeoutError();
     }
-    if (control_result == XFER_RESULT_SUCCESS) {
+    if (result == XFER_RESULT_SUCCESS) {
         return len;
     }
 
@@ -172,14 +292,22 @@ mp_int_t common_hal_usb_core_device_ctrl_transfer(usb_core_device_obj_t *self,
 }
 
 bool common_hal_usb_core_device_is_kernel_driver_active(usb_core_device_obj_t *self, mp_int_t interface) {
-    // TODO: Implement this when CP natively uses a keyboard.
+    #if CIRCUITPY_USB_KEYBOARD_WORKFLOW
+    if (usb_keyboard_in_use(self->device_number, interface)) {
+        return true;
+    }
+    #endif
     return false;
 }
 
 void common_hal_usb_core_device_detach_kernel_driver(usb_core_device_obj_t *self, mp_int_t interface) {
-    // TODO: Implement this when CP natively uses a keyboard.
+    #if CIRCUITPY_USB_KEYBOARD_WORKFLOW
+    usb_keyboard_detach(self->device_number, interface);
+    #endif
 }
 
 void common_hal_usb_core_device_attach_kernel_driver(usb_core_device_obj_t *self, mp_int_t interface) {
-    // TODO: Implement this when CP natively uses a keyboard.
+    #if CIRCUITPY_USB_KEYBOARD_WORKFLOW
+    usb_keyboard_attach(self->device_number, interface);
+    #endif
 }
diff --git a/shared-module/usb/core/Device.h b/shared-module/usb/core/Device.h
index 5959639fc8..bb32cb5766 100644
--- a/shared-module/usb/core/Device.h
+++ b/shared-module/usb/core/Device.h
@@ -32,6 +32,8 @@
 typedef struct {
     mp_obj_base_t base;
     uint8_t device_number;
+    uint8_t configuration_index; // not number
+    uint8_t open_endpoints[8];
 } usb_core_device_obj_t;
 
 #endif // MICROPY_INCLUDED_SHARED_MODULE_USB_CORE_DEVICE_H
diff --git a/supervisor/shared/background_callback.c b/supervisor/shared/background_callback.c
index 80f70b528a..17fed37e22 100644
--- a/supervisor/shared/background_callback.c
+++ b/supervisor/shared/background_callback.c
@@ -36,10 +36,14 @@
 
 STATIC volatile background_callback_t *volatile callback_head, *volatile callback_tail;
 
+#ifndef CALLBACK_CRITICAL_BEGIN
 #define CALLBACK_CRITICAL_BEGIN (common_hal_mcu_disable_interrupts())
+#endif
+#ifndef CALLBACK_CRITICAL_END
 #define CALLBACK_CRITICAL_END (common_hal_mcu_enable_interrupts())
+#endif
 
-MP_WEAK void port_wake_main_task(void) {
+MP_WEAK void PLACE_IN_ITCM(port_wake_main_task)(void) {
 }
 
 void PLACE_IN_ITCM(background_callback_add_core)(background_callback_t * cb) {
diff --git a/supervisor/shared/serial.c b/supervisor/shared/serial.c
index e683e8eb7c..7bf10ae530 100644
--- a/supervisor/shared/serial.c
+++ b/supervisor/shared/serial.c
@@ -238,6 +238,12 @@ char serial_read(void) {
     }
     #endif
 
+    #if CIRCUITPY_USB_KEYBOARD_WORKFLOW
+    if (usb_keyboard_chars_available() > 0) {
+        return usb_keyboard_read_char();
+    }
+    #endif
+
     if (port_serial_bytes_available() > 0) {
         return port_serial_read();
     }
@@ -279,6 +285,12 @@ bool serial_bytes_available(void) {
     }
     #endif
 
+    #if CIRCUITPY_USB_KEYBOARD_WORKFLOW
+    if (usb_keyboard_chars_available() > 0) {
+        return true;
+    }
+    #endif
+
     #if CIRCUITPY_USB_CDC
     if (usb_cdc_console_enabled() && tud_cdc_available() > 0) {
         return true;
diff --git a/supervisor/shared/usb/host_keyboard.c b/supervisor/shared/usb/host_keyboard.c
new file mode 100644
index 0000000000..831914d87a
--- /dev/null
+++ b/supervisor/shared/usb/host_keyboard.c
@@ -0,0 +1,241 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2023 Scott Shawcroft for Adafruit Industries
+ * Copyright (c) 2023 Jeff Epler for Adafruit Industries
+ *
+ * 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"
+
+#include "py/ringbuf.h"
+#include "py/runtime.h"
+#include "shared/runtime/interrupt_char.h"
+#include "supervisor/usb.h"
+
+// Buffer the incoming serial data in the background so that we can look for the
+// interrupt character.
+STATIC ringbuf_t _incoming_ringbuf;
+STATIC uint8_t _buf[16];
+
+uint8_t _dev_addr;
+uint8_t _interface;
+
+#define FLAG_ALPHABETIC (1)
+#define FLAG_SHIFT (2)
+#define FLAG_NUMLOCK (4)
+#define FLAG_CTRL (8)
+#define FLAG_LUT (16)
+
+const char *const lut[] = {
+    "!@#$%^&*()",                            /* 0 - shifted numeric keys */
+    "\r\x1b\10\t -=[]\\#;'`,./",             /* 1 - symbol keys */
+    "\n\x1b\177\t _+{}|~:\"~<>?",            /* 2 - shifted */
+    "\12\13\10\22",                          /* 3 - arrow keys RLDU */
+    "/*-+\n1234567890.",                     /* 4 - keypad w/numlock */
+    "/*-+\n\xff\2\xff\4\xff\3\xff\1\xff\xff.", /* 5 - keypad w/o numlock */
+};
+
+struct keycode_mapper {
+    uint8_t first, last, code, flags;
+} keycode_to_ascii[] = {
+    { HID_KEY_A, HID_KEY_Z, 'a', FLAG_ALPHABETIC, },
+
+    { HID_KEY_1, HID_KEY_9, 0, FLAG_SHIFT | FLAG_LUT, },
+    { HID_KEY_1, HID_KEY_9, '1', 0, },
+    { HID_KEY_0, HID_KEY_0, ')', FLAG_SHIFT, },
+    { HID_KEY_0, HID_KEY_0, '0', 0, },
+
+    { HID_KEY_ENTER, HID_KEY_ENTER, '\n', FLAG_CTRL },
+    { HID_KEY_ENTER, HID_KEY_SLASH, 2, FLAG_SHIFT | FLAG_LUT, },
+    { HID_KEY_ENTER, HID_KEY_SLASH, 1, FLAG_LUT, },
+
+    { HID_KEY_F1, HID_KEY_F1, 0x1e, 0, }, // help key on xerox 820 kbd
+
+    { HID_KEY_ARROW_RIGHT, HID_KEY_ARROW_UP, 3, FLAG_LUT },
+
+    { HID_KEY_KEYPAD_DIVIDE, HID_KEY_KEYPAD_DECIMAL, 4, FLAG_NUMLOCK | FLAG_LUT },
+    { HID_KEY_KEYPAD_DIVIDE, HID_KEY_KEYPAD_DECIMAL, 5, FLAG_LUT },
+};
+
+STATIC bool report_contains(const hid_keyboard_report_t *report, uint8_t key) {
+    for (int i = 0; i < 6; i++) {
+        if (report->keycode[i] == key) {
+            return true;
+        }
+    }
+    return false;
+}
+
+int old_ascii = -1;
+uint32_t repeat_timeout;
+// this matches Linux default of 500ms to first repeat, 1/20s thereafter
+const uint32_t default_repeat_time = 50;
+const uint32_t initial_repeat_time = 500;
+
+STATIC void send_ascii(uint8_t code, uint32_t repeat_time) {
+    old_ascii = code;
+    // repeat_timeout = millis() + repeat_time;
+    if (code == mp_interrupt_char) {
+        mp_sched_keyboard_interrupt();
+        return;
+    }
+    if (ringbuf_num_empty(&_incoming_ringbuf) == 0) {
+        // Drop on the floor
+        return;
+    }
+    ringbuf_put(&_incoming_ringbuf, code);
+}
+
+hid_keyboard_report_t old_report;
+
+STATIC void process_event(uint8_t dev_addr, uint8_t instance, const hid_keyboard_report_t *report) {
+    bool alt = report->modifier & 0x44;
+    bool shift = report->modifier & 0x22;
+    bool ctrl = report->modifier & 0x11;
+    bool caps = old_report.reserved & 1;
+    bool num = old_report.reserved & 2;
+    uint8_t code = 0;
+
+    if (report->keycode[0] == 1 && report->keycode[1] == 1) {
+        // keyboard says it has exceeded max kro
+        return;
+    }
+
+    // something was pressed or release, so cancel any key repeat
+    old_ascii = -1;
+
+    for (int i = 0; i < 6; i++) {
+        uint8_t keycode = report->keycode[i];
+        if (keycode == 0) {
+            continue;
+        }
+        if (report_contains(&old_report, keycode)) {
+            continue;
+        }
+
+        /* key is newly pressed */
+        if (keycode == HID_KEY_NUM_LOCK) {
+            num = !num;
+        } else if (keycode == HID_KEY_CAPS_LOCK) {
+            caps = !caps;
+        } else {
+            for (size_t j = 0; j < MP_ARRAY_SIZE(keycode_to_ascii); j++) {
+                struct keycode_mapper *mapper = &keycode_to_ascii[j];
+                if (!(keycode >= mapper->first && keycode <= mapper->last)) {
+                    continue;
+                }
+                if (mapper->flags & FLAG_SHIFT && !shift) {
+                    continue;
+                }
+                if (mapper->flags & FLAG_NUMLOCK && !num) {
+                    continue;
+                }
+                if (mapper->flags & FLAG_CTRL && !ctrl) {
+                    continue;
+                }
+                if (mapper->flags & FLAG_LUT) {
+                    code = lut[mapper->code][keycode - mapper->first];
+                } else {
+                    code = keycode - mapper->first + mapper->code;
+                }
+                if (mapper->flags & FLAG_ALPHABETIC) {
+                    if (shift ^ caps) {
+                        code ^= ('a' ^ 'A');
+                    }
+                }
+                if (ctrl) {
+                    code &= 0x1f;
+                }
+                if (alt) {
+                    code ^= 0x80;
+                }
+                send_ascii(code, initial_repeat_time);
+                break;
+            }
+        }
+    }
+
+    uint8_t leds = (caps | (num << 1));
+    if (leds != old_report.reserved) {
+        tuh_hid_set_report(dev_addr, instance /*idx*/, 0 /*report_id*/, HID_REPORT_TYPE_OUTPUT /*report_type*/, &leds, sizeof(leds));
+    }
+    old_report = *report;
+    old_report.reserved = leds;
+}
+
+bool usb_keyboard_in_use(uint8_t dev_addr, uint8_t interface) {
+    return _dev_addr == dev_addr && _interface == interface;
+}
+
+void usb_keyboard_detach(uint8_t dev_addr, uint8_t interface) {
+    if (!usb_keyboard_in_use(dev_addr, interface)) {
+        return;
+    }
+    _dev_addr = 0;
+    _interface = 0;
+}
+
+void usb_keyboard_attach(uint8_t dev_addr, uint8_t interface) {
+    if (usb_keyboard_in_use(dev_addr, interface) || _dev_addr != 0) {
+        return;
+    }
+    uint8_t const itf_protocol = tuh_hid_interface_protocol(dev_addr, interface);
+    if (itf_protocol == HID_ITF_PROTOCOL_KEYBOARD) {
+        _dev_addr = dev_addr;
+        _interface = interface;
+        tuh_hid_receive_report(dev_addr, interface);
+    }
+}
+
+void tuh_hid_mount_cb(uint8_t dev_addr, uint8_t interface, uint8_t const *desc_report, uint16_t desc_len) {
+    usb_keyboard_attach(dev_addr, interface);
+}
+
+void tuh_hid_umount_cb(uint8_t dev_addr, uint8_t interface) {
+    usb_keyboard_detach(dev_addr, interface);
+}
+
+void tuh_hid_report_received_cb(uint8_t dev_addr, uint8_t instance, uint8_t const *report, uint16_t len) {
+    if (len != sizeof(hid_keyboard_report_t)) {
+        return;
+    } else {
+        process_event(dev_addr, instance, (hid_keyboard_report_t *)report);
+    }
+    // continue to request to receive report
+    tuh_hid_receive_report(dev_addr, instance);
+}
+
+void usb_keyboard_init(void) {
+    ringbuf_init(&_incoming_ringbuf, _buf, sizeof(_buf) - 1);
+}
+
+bool usb_keyboard_chars_available(void) {
+    return ringbuf_num_filled(&_incoming_ringbuf) > 0;
+}
+
+char usb_keyboard_read_char(void) {
+    if (ringbuf_num_filled(&_incoming_ringbuf) > 0) {
+        return ringbuf_get(&_incoming_ringbuf);
+    }
+    return -1;
+}
diff --git a/supervisor/shared/usb/tusb_config.h b/supervisor/shared/usb/tusb_config.h
index c2ad1362a3..19f5c0a0ce 100644
--- a/supervisor/shared/usb/tusb_config.h
+++ b/supervisor/shared/usb/tusb_config.h
@@ -51,7 +51,7 @@ extern "C" {
 // When debugging TinyUSB, only output to the console UART link.
 #if CIRCUITPY_DEBUG_TINYUSB > 0 && defined(CIRCUITPY_CONSOLE_UART)
 #define CFG_TUSB_DEBUG              CIRCUITPY_DEBUG_TINYUSB
-#define CFG_TUSB_DEBUG_PRINTF       debug_uart_printf
+#define CFG_TUSB_DEBUG_PRINTF       console_uart_printf
 #endif
 
 /*------------- RTOS -------------*/
@@ -127,6 +127,10 @@ extern "C" {
 // --------------------------------------------------------------------
 
 #if CIRCUITPY_USB_HOST
+#define CFG_TUH_ENABLED 1
+
+// Always use PIO to do host on RP2.
+#define CFG_TUH_RPI_PIO_USB 1
 
 #if CIRCUITPY_USB_HOST_INSTANCE == 0
 #if USB_HIGHSPEED
@@ -147,10 +151,12 @@ extern "C" {
 #define CFG_TUH_ENUMERATION_BUFSIZE 256
 #endif
 
+#define CFG_TUH_HID                 2
 #define CFG_TUH_HUB                 1
 #define CFG_TUH_CDC                 0
 #define CFG_TUH_MSC                 0
 #define CFG_TUH_VENDOR              0
+#define CFG_TUH_API_EDPT_XFER       1
 
 // max device support (excluding hub device)
 #define CFG_TUH_DEVICE_MAX          (CFG_TUH_HUB ? 4 : 1) // hub typically has 4 ports
diff --git a/supervisor/shared/usb/usb.c b/supervisor/shared/usb/usb.c
index 133a97a99d..56c8b1897f 100644
--- a/supervisor/shared/usb/usb.c
+++ b/supervisor/shared/usb/usb.c
@@ -87,7 +87,8 @@ MP_WEAK void post_usb_init(void) {
 void usb_init(void) {
     init_usb_hardware();
 
-    tusb_init();
+    // Only init device. Host gets inited by the `usb_host` module common-hal.
+    tud_init(TUD_OPT_RHPORT);
 
     post_usb_init();
 
@@ -199,7 +200,7 @@ void usb_disconnect(void) {
 
 void usb_background(void) {
     if (usb_enabled()) {
-        #if CFG_TUSB_OS == OPT_OS_NONE
+        #if CFG_TUSB_OS == OPT_OS_NONE || CFG_TUSB_OS == OPT_OS_PICO
         tud_task();
         #if CIRCUITPY_USB_HOST
         tuh_task();
diff --git a/supervisor/shared/workflow.c b/supervisor/shared/workflow.c
index aebdcc821a..b4e7852b2a 100644
--- a/supervisor/shared/workflow.c
+++ b/supervisor/shared/workflow.c
@@ -112,6 +112,9 @@ void supervisor_workflow_start(void) {
     }
     #endif
 
+    #if CIRCUITPY_USB_KEYBOARD_WORKFLOW
+    usb_keyboard_init();
+    #endif
 }
 
 FRESULT supervisor_workflow_mkdir_parents(FATFS *fs, char *path) {
diff --git a/supervisor/supervisor.mk b/supervisor/supervisor.mk
index c461c5353f..374edf1310 100644
--- a/supervisor/supervisor.mk
+++ b/supervisor/supervisor.mk
@@ -161,8 +161,10 @@ ifeq ($(CIRCUITPY_USB),1)
 
   ifeq ($(CIRCUITPY_USB_HOST), 1)
     SRC_SUPERVISOR += \
+      lib/tinyusb/src/class/hid/hid_host.c \
       lib/tinyusb/src/host/hub.c \
       lib/tinyusb/src/host/usbh.c \
+      supervisor/shared/usb/host_keyboard.c \
 
   endif
 endif
diff --git a/supervisor/usb.h b/supervisor/usb.h
index 3c8da6f3b7..11a9cc27d6 100644
--- a/supervisor/usb.h
+++ b/supervisor/usb.h
@@ -96,4 +96,14 @@ bool usb_msc_lock(void);
 void usb_msc_unlock(void);
 #endif
 
+#if CIRCUITPY_USB_KEYBOARD_WORKFLOW
+void usb_keyboard_init(void);
+bool usb_keyboard_chars_available(void);
+char usb_keyboard_read_char(void);
+
+bool usb_keyboard_in_use(uint8_t dev_addr, uint8_t interface);
+void usb_keyboard_detach(uint8_t dev_addr, uint8_t interface);
+void usb_keyboard_attach(uint8_t dev_addr, uint8_t interface);
+#endif
+
 #endif // MICROPY_INCLUDED_SUPERVISOR_USB_H