async_spi: SPI transfers for asyncio

ports/raspberrypi/Makefile

@@ -595,6 +595,7 @@ SRC_C += \
 	audio_dma.c \
 	background.c \
 	peripherals/pins.c \
+	peripherals/spi.c \
 	lib/crypto-algorithms/sha256.c \
 	lib/tinyusb/src/portable/raspberrypi/rp2040/dcd_rp2040.c \
 	lib/tinyusb/src/portable/raspberrypi/rp2040/rp2040_usb.c \

ports/raspberrypi/common-hal/async_spi/SPI.c

@@ -0,0 +1,77 @@
+// This file is part of the CircuitPython project: https://circuitpython.org
+//
+// SPDX-FileCopyrightText: Copyright (c) 2026 Vladimir Smitka
+//
+// SPDX-License-Identifier: MIT
+
+#include "shared-bindings/async_spi/SPI.h"
+
+#include "py/runtime.h"
+#include "shared-bindings/microcontroller/Pin.h"
+
+void common_hal_async_spi_spi_construct(async_spi_spi_obj_t *self, const mcu_pin_obj_t *clock,
+    const mcu_pin_obj_t *mosi, const mcu_pin_obj_t *miso) {
+    rp2_spi_error_t error = rp2_spi_construct(&self->spi, clock, mosi, miso);
+    if (error == RP2_SPI_INVALID_PINS) {
+        raise_ValueError_invalid_pins();
+    }
+    if (error == RP2_SPI_IN_USE) {
+        mp_raise_ValueError(MP_ERROR_TEXT("SPI peripheral in use"));
+    }
+}
+
+bool common_hal_async_spi_spi_deinited(async_spi_spi_obj_t *self) {
+    return rp2_spi_deinited(&self->spi);
+}
+
+void common_hal_async_spi_spi_deinit(async_spi_spi_obj_t *self) {
+    rp2_spi_deinit(&self->spi);
+}
+
+void *common_hal_async_spi_spi_configure_start(async_spi_spi_obj_t *self, uint32_t baudrate,
+    uint8_t polarity, uint8_t phase, uint8_t bits, circuitpy_async_flag_t *done) {
+    rp2_spi_configure_start(&self->spi, baudrate, polarity, phase, bits, done);
+    return self;
+}
+
+mp_obj_t common_hal_async_spi_spi_configure_end(void *context, circuitpy_async_flag_t *done) {
+    return mp_const_none;
+}
+
+void common_hal_async_spi_spi_configure_cancel(void *context, circuitpy_async_flag_t *done) {
+    async_spi_spi_obj_t *self = context;
+    rp2_spi_configure_cancel(&self->spi, done);
+}
+
+uint32_t common_hal_async_spi_spi_get_frequency(async_spi_spi_obj_t *self) {
+    return self->spi.real_frequency;
+}
+
+void *common_hal_async_spi_spi_write_start(async_spi_spi_obj_t *self, const uint8_t *data,
+    size_t len, circuitpy_async_flag_t *done) {
+    rp2_spi_write_start(&self->spi, data, len, done);
+    return self;
+}
+
+void *common_hal_async_spi_spi_readinto_start(async_spi_spi_obj_t *self, uint8_t *data,
+    size_t len, uint8_t write_value, circuitpy_async_flag_t *done) {
+    rp2_spi_read_start(&self->spi, data, len, write_value, done);
+    return self;
+}
+
+void *common_hal_async_spi_spi_write_readinto_start(async_spi_spi_obj_t *self,
+    const uint8_t *data_out, uint8_t *data_in, size_t len, circuitpy_async_flag_t *done) {
+    rp2_spi_transfer_start(&self->spi, data_out, data_in, len, done);
+    return self;
+}
+
+mp_obj_t common_hal_async_spi_spi_transfer_end(void *context, circuitpy_async_flag_t *done) {
+    async_spi_spi_obj_t *self = context;
+    rp2_spi_stop(&self->spi, done);
+    return mp_const_none;
+}
+
+void common_hal_async_spi_spi_transfer_cancel(void *context, circuitpy_async_flag_t *done) {
+    async_spi_spi_obj_t *self = context;
+    rp2_spi_stop(&self->spi, done);
+}

ports/raspberrypi/common-hal/async_spi/SPI.h

@@ -0,0 +1,15 @@
+// This file is part of the CircuitPython project: https://circuitpython.org
+//
+// SPDX-FileCopyrightText: Copyright (c) 2026 Vladimir Smitka
+//
+// SPDX-License-Identifier: MIT
+
+#pragma once
+
+#include "py/obj.h"
+#include "peripherals/spi.h"
+
+typedef struct {
+    mp_obj_base_t base;
+    rp2_spi_t spi;
+} async_spi_spi_obj_t;

ports/raspberrypi/common-hal/async_spi/__init__.c

@@ -0,0 +1,7 @@
+// This file is part of the CircuitPython project: https://circuitpython.org
+//
+// SPDX-FileCopyrightText: Copyright (c) 2026 Vladimir Smitka
+//
+// SPDX-License-Identifier: MIT
+
+// No async_spi module functions.