Initial commit

10 files changed, 572 insertions, 0 deletions

diff --git a/py/circuitpy_defns.mk b/py/circuitpy_defns.mk
index ccdf973e9..9318bd466 100644
--- a/py/circuitpy_defns.mk
+++ b/py/circuitpy_defns.mk
@@ -133,6 +133,9 @@ endif
 ifeq ($(CIRCUITPY_BOARD),1)
 SRC_PATTERNS += board/%
 endif
+ifeq ($(CIRCUITPY_BUSDEVICE),1)
+SRC_PATTERNS += busdevice/%
+endif
 ifeq ($(CIRCUITPY_BUSIO),1)
 SRC_PATTERNS += busio/% bitbangio/OneWire.%
 endif
@@ -432,6 +435,8 @@ SRC_SHARED_MODULE_ALL = \
 	bitbangio/SPI.c \
 	bitbangio/__init__.c \
 	board/__init__.c \
+	busdevice/__init__.c \
+	busdevice/I2CDevice.c \
 	busio/OneWire.c \
 	displayio/Bitmap.c \
 	displayio/ColorConverter.c \
diff --git a/py/circuitpy_mpconfig.h b/py/circuitpy_mpconfig.h
index 1e01bd9c5..240fac189 100644
--- a/py/circuitpy_mpconfig.h
+++ b/py/circuitpy_mpconfig.h
@@ -324,6 +324,13 @@ extern const struct _mp_obj_module_t board_module;
 #define BOARD_UART_ROOT_POINTER
 #endif
 
+#if CIRCUITPY_BUSDEVICE
+extern const struct _mp_obj_module_t busdevice_module;
+#define BUSDEVICE_MODULE           { MP_OBJ_NEW_QSTR(MP_QSTR_busdevice), (mp_obj_t)&busdevice_module },
+#else
+#define BUSDEVICE_MODULE
+#endif
+
 #if CIRCUITPY_BUSIO
 extern const struct _mp_obj_module_t busio_module;
 #define BUSIO_MODULE           { MP_OBJ_NEW_QSTR(MP_QSTR_busio), (mp_obj_t)&busio_module },
@@ -773,6 +780,7 @@ extern const struct _mp_obj_module_t wifi_module;
     BITBANGIO_MODULE \
     BLEIO_MODULE \
     BOARD_MODULE \
+    BUSDEVICE_MODULE \
     BUSIO_MODULE \
     CAMERA_MODULE \
     CANIO_MODULE \
diff --git a/py/circuitpy_mpconfig.mk b/py/circuitpy_mpconfig.mk
index a6aabec33..1f96a8f2d 100644
--- a/py/circuitpy_mpconfig.mk
+++ b/py/circuitpy_mpconfig.mk
@@ -90,6 +90,9 @@ CFLAGS += -DCIRCUITPY_BLEIO=$(CIRCUITPY_BLEIO)
 CIRCUITPY_BOARD ?= 1
 CFLAGS += -DCIRCUITPY_BOARD=$(CIRCUITPY_BOARD)
 
+CIRCUITPY_BUSDEVICE ?= 1
+CFLAGS += -DCIRCUITPY_BUSDEVICE=$(CIRCUITPY_BUSDEVICE)
+
 CIRCUITPY_BUSIO ?= 1
 CFLAGS += -DCIRCUITPY_BUSIO=$(CIRCUITPY_BUSIO)
 
diff --git a/shared-bindings/busdevice/I2CDevice.c b/shared-bindings/busdevice/I2CDevice.c
new file mode 100644
index 000000000..02dac6a95
--- /dev/null
+++ b/shared-bindings/busdevice/I2CDevice.c
@@ -0,0 +1,246 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2016 Scott Shawcroft
+ *
+ * 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 contains all of the Python API definitions for the
+// busio.I2C class.
+
+#include "shared-bindings/microcontroller/Pin.h"
+#include "shared-bindings/busdevice/I2CDevice.h"
+#include "shared-bindings/util.h"
+#include "shared-module/busdevice/I2CDevice.h"
+
+#include "lib/utils/buffer_helper.h"
+#include "lib/utils/context_manager_helpers.h"
+#include "py/runtime.h"
+#include "supervisor/shared/translate.h"
+
+//| class I2CDevice:
+//|     """Two wire serial protocol"""
+//|
+//|     def __init__(self, i2c, device_address, probe=True) -> None:
+//|
+//|         ...
+//|
+STATIC mp_obj_t busdevice_i2cdevice_make_new(const mp_obj_type_t *type, size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
+    busdevice_i2cdevice_obj_t *self = m_new_obj(busdevice_i2cdevice_obj_t);
+    self->base.type = &busdevice_i2cdevice_type;
+    enum { ARG_i2c, ARG_device_address, ARG_probe };
+    static const mp_arg_t allowed_args[] = {
+        { MP_QSTR_i2c, MP_ARG_REQUIRED | MP_ARG_OBJ },
+        { MP_QSTR_device_address, MP_ARG_REQUIRED | MP_ARG_INT },
+        { MP_QSTR_probe, MP_ARG_BOOL, {.u_bool = true} },
+    };
+    mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
+    mp_arg_parse_all(n_args, pos_args, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
+
+    busio_i2c_obj_t* i2c = args[ARG_i2c].u_obj;
+
+    common_hal_busdevice_i2cdevice_construct(self, i2c, args[ARG_device_address].u_int, args[ARG_probe].u_bool);
+    return (mp_obj_t)self;
+}
+
+//|     def __enter__(self) -> None:
+//|         """Automatically initializes the hardware on context exit. See FIX
+//|         :ref:`lifetime-and-contextmanagers` for more info."""
+//|         ...
+//|
+STATIC mp_obj_t busdevice_i2cdevice_obj___enter__(mp_obj_t self_in) {
+    common_hal_busdevice_i2cdevice_lock(self_in);
+    return self_in;
+}
+STATIC MP_DEFINE_CONST_FUN_OBJ_1(busdevice_i2cdevice___enter___obj, busdevice_i2cdevice_obj___enter__);
+
+//|     def __exit__(self) -> None:
+//|         """Automatically deinitializes the hardware on context exit. See
+//|         :ref:`lifetime-and-contextmanagers` for more info."""
+//|         ...
+//|
+STATIC mp_obj_t busdevice_i2cdevice_obj___exit__(size_t n_args, const mp_obj_t *args) {
+    common_hal_busdevice_i2cdevice_unlock(args[0]);
+    return mp_const_none;
+}
+STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(busdevice_i2cdevice___exit___obj, 4, 4, busdevice_i2cdevice_obj___exit__);
+
+STATIC void readinto(busdevice_i2cdevice_obj_t *self, mp_obj_t buffer, int32_t start, mp_int_t end) {
+    mp_buffer_info_t bufinfo;
+    mp_get_buffer_raise(buffer, &bufinfo, MP_BUFFER_WRITE);
+
+    size_t length = bufinfo.len;
+    normalize_buffer_bounds(&start, end, &length);
+    if (length == 0) {
+        mp_raise_ValueError(translate("Buffer must be at least length 1"));
+    }
+
+    uint8_t status = common_hal_busdevice_i2cdevice_readinto(self, ((uint8_t*)bufinfo.buf) + start, length);
+    if (status != 0) {
+        mp_raise_OSError(status);
+    }
+}
+
+STATIC mp_obj_t busdevice_i2cdevice_readinto(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
+    enum { ARG_buffer, ARG_start, ARG_end };
+    static const mp_arg_t allowed_args[] = {
+        { MP_QSTR_buffer,     MP_ARG_REQUIRED | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
+        { MP_QSTR_start,      MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0} },
+        { MP_QSTR_end,        MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = INT_MAX} },
+    };
+    
+    busdevice_i2cdevice_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);
+
+    readinto(self, args[ARG_buffer].u_obj, args[ARG_start].u_int, args[ARG_end].u_int);
+    return mp_const_none;
+}
+STATIC MP_DEFINE_CONST_FUN_OBJ_KW(busdevice_i2cdevice_readinto_obj, 2, busdevice_i2cdevice_readinto);
+
+
+STATIC void write(busdevice_i2cdevice_obj_t *self, mp_obj_t buffer, int32_t start, mp_int_t end) {
+    mp_buffer_info_t bufinfo;
+    mp_get_buffer_raise(buffer, &bufinfo, MP_BUFFER_READ);
+
+    size_t length = bufinfo.len;
+    normalize_buffer_bounds(&start, end, &length);
+    if (length == 0) {
+        mp_raise_ValueError(translate("Buffer must be at least length 1"));
+    }
+
+    uint8_t status = common_hal_busdevice_i2cdevice_write(self, ((uint8_t*)bufinfo.buf) + start, length);
+    if (status != 0) {
+        mp_raise_OSError(status);
+    }
+}
+
+STATIC mp_obj_t busdevice_i2cdevice_write(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
+    enum { ARG_buffer, ARG_start, ARG_end };
+    static const mp_arg_t allowed_args[] = {
+        { MP_QSTR_buffer,     MP_ARG_REQUIRED | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
+        { MP_QSTR_start,      MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0} },
+        { MP_QSTR_end,        MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = INT_MAX} },
+    };
+    busdevice_i2cdevice_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);
+
+    write(self, args[ARG_buffer].u_obj, args[ARG_start].u_int, args[ARG_end].u_int);
+    return mp_const_none;
+}
+MP_DEFINE_CONST_FUN_OBJ_KW(busdevice_i2cdevice_write_obj, 2, busdevice_i2cdevice_write);
+
+
+/*STATIC void write_then_readinto(busdevice_i2cdevice_obj_t *self, mp_obj_t out_buffer, mp_obj_t in_buffer, 
+                                int32_t out_start, mp_int_t out_end, int32_t in_start, mp_int_t in_end) {
+    mp_buffer_info_t out_bufinfo;
+    mp_get_buffer_raise(out_buffer, &out_bufinfo, MP_BUFFER_READ);
+
+    size_t out_length = out_bufinfo.len;
+    normalize_buffer_bounds(&out_start, out_end, &out_length);
+    if (out_length == 0) {
+        mp_raise_ValueError(translate("Buffer must be at least length 1"));
+    }
+
+    mp_buffer_info_t in_bufinfo;
+    mp_get_buffer_raise(in_buffer, &in_bufinfo, MP_BUFFER_WRITE);
+
+    size_t in_length = in_bufinfo.len;
+    normalize_buffer_bounds(&in_start, in_end, &in_length);
+    if (in_length == 0) {
+        mp_raise_ValueError(translate("Buffer must be at least length 1"));
+    }
+
+    uint8_t status = common_hal_busdevice_i2cdevice_write_then_readinto(self, out_buffer, in_buffer, out_length, in_length);
+    if (status != 0) {
+        mp_raise_OSError(status);
+    }
+}*/
+
+STATIC mp_obj_t busdevice_i2cdevice_write_then_readinto(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
+    enum { ARG_out_buffer, ARG_in_buffer, ARG_out_start, ARG_out_end, ARG_in_start, ARG_in_end };
+    static const mp_arg_t allowed_args[] = {
+        { MP_QSTR_out_buffer,    MP_ARG_REQUIRED | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
+        { MP_QSTR_in_buffer,     MP_ARG_REQUIRED | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
+        { MP_QSTR_out_start,     MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0} },
+        { MP_QSTR_out_end,       MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = INT_MAX} },
+        { MP_QSTR_in_start,      MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0} },
+        { MP_QSTR_in_end,        MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = INT_MAX} },
+    };
+    busdevice_i2cdevice_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);
+
+    write(self, args[ARG_out_buffer].u_obj, args[ARG_out_start].u_int, args[ARG_out_end].u_int);
+    
+    readinto(self, args[ARG_in_buffer].u_obj, args[ARG_in_start].u_int, args[ARG_in_end].u_int);
+
+    return mp_const_none;
+}
+MP_DEFINE_CONST_FUN_OBJ_KW(busdevice_i2cdevice_write_then_readinto_obj, 3, busdevice_i2cdevice_write_then_readinto);
+
+
+STATIC mp_obj_t busdevice_i2cdevice___probe_for_device(mp_obj_t self_in) {
+    //busdevice_i2cdevice_obj_t *self = self_in;
+
+    //common_hal_busdevice_i2cdevice_lock(self_in);
+
+/*
+    uint8_t buffer;
+    mp_buffer_info_t bufinfo;
+    mp_get_buffer_raise(&buffer, &bufinfo, MP_BUFFER_WRITE);
+
+    uint8_t status = common_hal_busdevice_i2cdevice_readinto(self_in, (uint8_t*)bufinfo.buf, 1);
+    if (status != 0) {
+        common_hal_busdevice_i2cdevice_unlock(self_in);
+        mp_raise_ValueError_varg(translate("No I2C device at address: %x"), self->device_address);
+    }
+*/
+    //common_hal_busdevice_i2cdevice_unlock(self_in);
+
+    return mp_const_none;
+}
+MP_DEFINE_CONST_FUN_OBJ_1(busdevice_i2cdevice___probe_for_device_obj, busdevice_i2cdevice___probe_for_device);
+
+
+STATIC const mp_rom_map_elem_t busdevice_i2cdevice_locals_dict_table[] = {
+    { MP_ROM_QSTR(MP_QSTR___enter__), MP_ROM_PTR(&busdevice_i2cdevice___enter___obj) },
+    { MP_ROM_QSTR(MP_QSTR___exit__), MP_ROM_PTR(&busdevice_i2cdevice___exit___obj) },
+    { MP_ROM_QSTR(MP_QSTR_readinto), MP_ROM_PTR(&busdevice_i2cdevice_readinto_obj) },
+    { MP_ROM_QSTR(MP_QSTR_write), MP_ROM_PTR(&busdevice_i2cdevice_write_obj) },
+    { MP_ROM_QSTR(MP_QSTR_write_then_readinto), MP_ROM_PTR(&busdevice_i2cdevice_write_then_readinto_obj) },
+    { MP_ROM_QSTR(MP_QSTR___probe_for_device), MP_ROM_PTR(&busdevice_i2cdevice___probe_for_device_obj) },
+};
+
+
+STATIC MP_DEFINE_CONST_DICT(busdevice_i2cdevice_locals_dict, busdevice_i2cdevice_locals_dict_table);
+
+const mp_obj_type_t busdevice_i2cdevice_type = {
+   { &mp_type_type },
+   .name = MP_QSTR_I2CDevice,
+   .make_new = busdevice_i2cdevice_make_new,
+   .locals_dict = (mp_obj_dict_t*)&busdevice_i2cdevice_locals_dict,
+};
\ No newline at end of file
diff --git a/shared-bindings/busdevice/I2CDevice.h b/shared-bindings/busdevice/I2CDevice.h
new file mode 100644
index 000000000..bc85023d7
--- /dev/null
+++ b/shared-bindings/busdevice/I2CDevice.h
@@ -0,0 +1,58 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2020 Mark Komus
+ *
+ * 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.
+ */
+
+// Machine is the HAL for low-level, hardware accelerated functions. It is not
+// meant to simplify APIs, its only meant to unify them so that other modules
+// do not require port specific logic.
+//
+// This file includes externs for all functions a port should implement to
+// support the machine module.
+
+#ifndef MICROPY_INCLUDED_SHARED_BINDINGS_BUSDEVICE_I2CDEVICE_H
+#define MICROPY_INCLUDED_SHARED_BINDINGS_BUSDEVICE_I2CDEVICE_H
+
+#include "py/obj.h"
+
+#include "common-hal/microcontroller/Pin.h"
+#include "shared-module/busdevice/I2CDevice.h"
+#include "shared-bindings/busio/I2C.h"
+
+// Type object used in Python. Should be shared between ports.
+extern const mp_obj_type_t busdevice_i2cdevice_type;
+
+// Initializes the hardware peripheral.
+extern void common_hal_busdevice_i2cdevice_construct(busdevice_i2cdevice_obj_t *self, busio_i2c_obj_t *i2c, uint8_t device_address, bool probe);
+extern void common_hal_busdevice_i2cdevice___enter__(busdevice_i2cdevice_obj_t *self);
+extern void common_hal_busdevice_i2cdevice___exit__(busdevice_i2cdevice_obj_t *self);
+extern uint8_t common_hal_busdevice_i2cdevice_readinto(busdevice_i2cdevice_obj_t *self, mp_obj_t buffer, size_t length);
+extern uint8_t common_hal_busdevice_i2cdevice_write(busdevice_i2cdevice_obj_t *self, mp_obj_t buffer, size_t length);
+extern uint8_t common_hal_busdevice_i2cdevice_write_then_readinto(busdevice_i2cdevice_obj_t *self, mp_obj_t out_buffer,
+                                                                 mp_obj_t in_buffer, size_t out_length, size_t in_length);
+extern uint8_t common_hal_busdevice_i2cdevice___probe_for_device(busdevice_i2cdevice_obj_t *self);
+extern void common_hal_busdevice_i2cdevice_lock(busdevice_i2cdevice_obj_t *self);
+extern void common_hal_busdevice_i2cdevice_unlock(busdevice_i2cdevice_obj_t *self);
+
+#endif // MICROPY_INCLUDED_SHARED_BINDINGS_BUSDEVICE_I2CDEVICE_H
diff --git a/shared-bindings/busdevice/__init__.c b/shared-bindings/busdevice/__init__.c
new file mode 100644
index 000000000..6b24160a0
--- /dev/null
+++ b/shared-bindings/busdevice/__init__.c
@@ -0,0 +1,79 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2016 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 <stdint.h>
+
+#include "py/obj.h"
+#include "py/runtime.h"
+#include "py/mphal.h"
+#include "py/objproperty.h"
+
+#include "shared-bindings/busdevice/__init__.h"
+#include "shared-bindings/busdevice/I2CDevice.h"
+
+
+//| """Hardware accelerated external bus access
+//|
+//| The `busio` module contains classes to support a variety of serial
+//| protocols.
+//|
+//| When the microcontroller does not support the behavior in a hardware
+//| accelerated fashion it may internally use a bitbang routine. However, if
+//| hardware support is available on a subset of pins but not those provided,
+//| then a RuntimeError will be raised. Use the `bitbangio` module to explicitly
+//| bitbang a serial protocol on any general purpose pins.
+//|
+//| All classes change hardware state and should be deinitialized when they
+//| are no longer needed if the program continues after use. To do so, either
+//| call :py:meth:`!deinit` or use a context manager. See
+//| :ref:`lifetime-and-contextmanagers` for more info.
+//|
+//| For example::
+//|
+//|   import busio
+//|   from board import *
+//|
+//|   i2c = busio.I2C(SCL, SDA)
+//|   print(i2c.scan())
+//|   i2c.deinit()
+//|
+//| This example will initialize the the device, run
+//| :py:meth:`~busio.I2C.scan` and then :py:meth:`~busio.I2C.deinit` the
+//| hardware. The last step is optional because CircuitPython automatically
+//| resets hardware after a program finishes."""
+//|
+
+STATIC const mp_rom_map_elem_t busdevice_module_globals_table[] = {
+    { MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_busdevice) },
+    { MP_ROM_QSTR(MP_QSTR_I2CDevice),   MP_ROM_PTR(&busdevice_i2cdevice_type) },
+};
+
+STATIC MP_DEFINE_CONST_DICT(busdevice_module_globals, busdevice_module_globals_table);
+
+const mp_obj_module_t busdevice_module = {
+    .base = { &mp_type_module },
+    .globals = (mp_obj_dict_t*)&busdevice_module_globals,
+};
diff --git a/shared-bindings/busdevice/__init__.h b/shared-bindings/busdevice/__init__.h
new file mode 100644
index 000000000..4a669807b
--- /dev/null
+++ b/shared-bindings/busdevice/__init__.h
@@ -0,0 +1,32 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2020 Mark Komus
+ *
+ * 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_SHARED_BINDINGS_BUSDEVICE___INIT___H
+#define MICROPY_INCLUDED_SHARED_BINDINGS_BUSDEVICE___INIT___H
+
+// Nothing now.
+
+#endif  // MICROPY_INCLUDED_SHARED_BINDINGS_BUSDEVICE___INIT___H
diff --git a/shared-module/busdevice/I2CDevice.c b/shared-module/busdevice/I2CDevice.c
new file mode 100644
index 000000000..30f4aad33
--- /dev/null
+++ b/shared-module/busdevice/I2CDevice.c
@@ -0,0 +1,101 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2017 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 "shared-bindings/busdevice/I2CDevice.h"
+#include "shared-bindings/busio/I2C.h"
+#include "py/mperrno.h"
+#include "py/nlr.h"
+
+void common_hal_busdevice_i2cdevice_construct(busdevice_i2cdevice_obj_t *self, busio_i2c_obj_t *i2c, uint8_t device_address, bool probe) {
+    self->i2c = i2c;
+    self->device_address = device_address;
+    self->probe = probe;
+
+    if (self->probe == true) {
+        common_hal_busdevice_i2cdevice___probe_for_device(self);
+    }
+}
+
+void common_hal_busdevice_i2cdevice_lock(busdevice_i2cdevice_obj_t *self) {
+    bool success = false;
+    while (!success) {
+        success = common_hal_busio_i2c_try_lock(self->i2c);
+    }
+}
+
+void common_hal_busdevice_i2cdevice_unlock(busdevice_i2cdevice_obj_t *self) {
+    common_hal_busio_i2c_unlock(self->i2c);
+}
+
+uint8_t common_hal_busdevice_i2cdevice_readinto(busdevice_i2cdevice_obj_t *self, mp_obj_t buffer, size_t length) {
+    uint8_t status = common_hal_busio_i2c_read(self->i2c, self->device_address, buffer, length);
+
+    return status;
+}
+
+uint8_t common_hal_busdevice_i2cdevice_write(busdevice_i2cdevice_obj_t *self, mp_obj_t buffer, size_t length) {
+    uint8_t status = common_hal_busio_i2c_write(self->i2c, self->device_address, buffer, length, true);
+
+    return status;
+}
+
+uint8_t common_hal_busdevice_i2cdevice_write_then_readinto(busdevice_i2cdevice_obj_t *self, mp_obj_t out_buffer, mp_obj_t in_buffer,
+                    size_t out_length, size_t in_length) {
+    uint8_t status = 0;
+
+    status = common_hal_busio_i2c_write(self->i2c, self->device_address, out_buffer, out_length, true);
+
+    status = common_hal_busio_i2c_read(self->i2c, self->device_address, in_buffer, in_length);
+
+    return status;
+}
+
+uint8_t common_hal_busdevice_i2cdevice___probe_for_device(busdevice_i2cdevice_obj_t *self) {
+
+
+
+
+    // write ""
+
+
+/*
+            while not self.i2c.try_lock():
+            pass
+        try:
+            self.i2c.writeto(self.device_address, b"")
+        except OSError:
+            # some OS's dont like writing an empty bytesting...
+            # Retry by reading a byte
+            try:
+                result = bytearray(1)
+                self.i2c.readfrom_into(self.device_address, result)
+            except OSError:
+                raise ValueError("No I2C device at address: %x" % self.device_address)
+        finally:
+            self.i2c.unlock()
+*/
+    return 0;
+}
diff --git a/shared-module/busdevice/I2CDevice.h b/shared-module/busdevice/I2CDevice.h
new file mode 100644
index 000000000..c872704db
--- /dev/null
+++ b/shared-module/busdevice/I2CDevice.h
@@ -0,0 +1,40 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2017 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.
+ */
+
+#ifndef MICROPY_INCLUDED_ATMEL_SAMD_SHARED_MODULE_BUSDEVICE_I2CDEVICE_H
+#define MICROPY_INCLUDED_ATMEL_SAMD_SHARED_MODULE_BUSDEVICE_I2CDEVICE_H
+
+#include "py/obj.h"
+#include "common-hal/busio/I2C.h"
+
+typedef struct {
+    mp_obj_base_t base;
+    busio_i2c_obj_t *i2c;
+    uint8_t device_address;
+    bool probe;
+} busdevice_i2cdevice_obj_t;
+
+#endif // MICROPY_INCLUDED_ATMEL_SAMD_SHARED_MODULE_BUSDEVICE_I2CDEVICE_H
diff --git a/shared-module/busdevice/__init__.c b/shared-module/busdevice/__init__.c
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/shared-module/busdevice/__init__.c