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+/*
+ * 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/busio/I2C.h"
+
+#include "lib/utils/context_manager_helpers.h"
+#include "py/runtime.h"
+//| .. currentmodule:: busio
+//|
+//| :class:`I2C` --- Two wire serial protocol
+//| ------------------------------------------
+//|
+//| .. class:: I2C(scl, sda, \*, frequency=400000)
+//|
+//| I2C is a two-wire protocol for communicating between devices. At the
+//| physical level it consists of 2 wires: SCL and SDA, the clock and data
+//| lines respectively.
+//|
+//| .. seealso:: Using this class directly requires careful lock management.
+//| Instead, use :class:`~adafruit_bus_device.i2c_device.I2CDevice` to
+//| manage locks.
+//|
+//| .. seealso:: Using this class to directly read registers requires manual
+//| bit unpacking. Instead, use an existing driver or make one with
+//| :ref:`Register <register-module-reference>` data descriptors.
+//|
+//| :param ~microcontroller.Pin scl: The clock pin
+//| :param ~microcontroller.Pin sda: The data pin
+//| :param int frequency: The clock frequency in Hertz
+//|
+STATIC mp_obj_t busio_i2c_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *pos_args) {
+ mp_arg_check_num(n_args, n_kw, 0, MP_OBJ_FUN_ARGS_MAX, true);
+ busio_i2c_obj_t *self = m_new_obj(busio_i2c_obj_t);
+ self->base.type = &busio_i2c_type;
+ mp_map_t kw_args;
+ mp_map_init_fixed_table(&kw_args, n_kw, pos_args + n_args);
+ enum { ARG_scl, ARG_sda, ARG_frequency };
+ static const mp_arg_t allowed_args[] = {
+ { MP_QSTR_scl, MP_ARG_REQUIRED | MP_ARG_OBJ },
+ { MP_QSTR_sda, MP_ARG_REQUIRED | MP_ARG_OBJ },
+ { MP_QSTR_frequency, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 400000} },
+ };
+ 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);
+ assert_pin(args[ARG_scl].u_obj, false);
+ assert_pin(args[ARG_sda].u_obj, false);
+ const mcu_pin_obj_t* scl = MP_OBJ_TO_PTR(args[ARG_scl].u_obj);
+ assert_pin_free(scl);
+ const mcu_pin_obj_t* sda = MP_OBJ_TO_PTR(args[ARG_sda].u_obj);
+ assert_pin_free(sda);
+ common_hal_busio_i2c_construct(self, scl, sda, args[ARG_frequency].u_int);
+ return (mp_obj_t)self;
+}
+
+//| .. method:: I2C.deinit()
+//|
+//| Releases control of the underlying hardware so other classes can use it.
+//|
+STATIC mp_obj_t busio_i2c_obj_deinit(mp_obj_t self_in) {
+ busio_i2c_obj_t *self = MP_OBJ_TO_PTR(self_in);
+ common_hal_busio_i2c_deinit(self);
+ return mp_const_none;
+}
+MP_DEFINE_CONST_FUN_OBJ_1(busio_i2c_deinit_obj, busio_i2c_obj_deinit);
+
+//| .. method:: I2C.__enter__()
+//|
+//| No-op used in Context Managers.
+//|
+// Provided by context manager helper.
+
+//| .. method:: I2C.__exit__()
+//|
+//| Automatically deinitializes the hardware on context exit.
+//|
+STATIC mp_obj_t busio_i2c_obj___exit__(size_t n_args, const mp_obj_t *args) {
+ (void)n_args;
+ common_hal_busio_i2c_deinit(args[0]);
+ return mp_const_none;
+}
+STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(busio_i2c___exit___obj, 4, 4, busio_i2c_obj___exit__);
+
+static void check_lock(busio_i2c_obj_t *self) {
+ if (!common_hal_busio_i2c_has_lock(self)) {
+ mp_raise_RuntimeError("Function requires lock.");
+ }
+}
+
+//| .. method:: I2C.scan()
+//|
+//| Scan all I2C addresses between 0x08 and 0x77 inclusive and return a
+//| list of those that respond.
+//|
+//| :return: List of device ids on the I2C bus
+//| :rtype: list
+//|
+STATIC mp_obj_t busio_i2c_scan(mp_obj_t self_in) {
+ busio_i2c_obj_t *self = MP_OBJ_TO_PTR(self_in);
+ check_lock(self);
+ mp_obj_t list = mp_obj_new_list(0, NULL);
+ // 7-bit addresses 0b0000xxx and 0b1111xxx are reserved
+ for (int addr = 0x08; addr < 0x78; ++addr) {
+ bool success = common_hal_busio_i2c_probe(self, addr);
+ if (success) {
+ mp_obj_list_append(list, MP_OBJ_NEW_SMALL_INT(addr));
+ }
+ }
+ return list;
+}
+MP_DEFINE_CONST_FUN_OBJ_1(busio_i2c_scan_obj, busio_i2c_scan);
+
+//| .. method:: I2C.try_lock()
+//|
+//| Attempts to grab the I2C lock. Returns True on success.
+//|
+//| :return: True when lock has been grabbed
+//| :rtype: bool
+//|
+STATIC mp_obj_t busio_i2c_obj_try_lock(mp_obj_t self_in) {
+ return mp_obj_new_bool(common_hal_busio_i2c_try_lock(MP_OBJ_TO_PTR(self_in)));
+}
+MP_DEFINE_CONST_FUN_OBJ_1(busio_i2c_try_lock_obj, busio_i2c_obj_try_lock);
+
+//| .. method:: I2C.unlock()
+//|
+//| Releases the I2C lock.
+//|
+STATIC mp_obj_t busio_i2c_obj_unlock(mp_obj_t self_in) {
+ common_hal_busio_i2c_unlock(MP_OBJ_TO_PTR(self_in));
+ return mp_const_none;
+}
+MP_DEFINE_CONST_FUN_OBJ_1(busio_i2c_unlock_obj, busio_i2c_obj_unlock);
+
+//| .. method:: I2C.readfrom_into(address, buffer, \*, start=0, end=len(buffer))
+//|
+//| Read into ``buffer`` from the slave specified by ``address``.
+//| The number of bytes read will be the length of ``buffer``.
+//|
+//| If ``start`` or ``end`` is provided, then the buffer will be sliced
+//| as if ``buffer[start:end]``. This will not cause an allocation like
+//| ``buf[start:end]`` will so it saves memory.
+//|
+//| :param int address: 7-bit device address
+//| :param bytearray buffer: buffer to write into
+//| :param int start: Index to start writing at
+//| :param int end: Index to write up to but not include
+//|
+STATIC mp_obj_t busio_i2c_readfrom_into(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
+ enum { ARG_address, ARG_buffer, ARG_start, ARG_end };
+ static const mp_arg_t allowed_args[] = {
+ { MP_QSTR_address, MP_ARG_REQUIRED | MP_ARG_INT, {.u_int = 0} },
+ { 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} },
+ };
+ busio_i2c_obj_t *self = MP_OBJ_TO_PTR(pos_args[0]);
+ check_lock(self);
+ 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);
+
+ mp_buffer_info_t bufinfo;
+ mp_get_buffer_raise(args[ARG_buffer].u_obj, &bufinfo, MP_BUFFER_WRITE);
+ int32_t end = args[ARG_end].u_int;
+ if (end < 0) {
+ end += bufinfo.len;
+ }
+ uint32_t start = args[ARG_start].u_int;
+ uint32_t len = end - start;
+ if ((uint32_t) end < start) {
+ len = 0;
+ } else if (len > bufinfo.len) {
+ len = bufinfo.len;
+ }
+ uint8_t status = common_hal_busio_i2c_read(self, args[ARG_address].u_int, ((uint8_t*)bufinfo.buf) + start, len);
+ if (status != 0) {
+ mp_raise_OSError(status);
+ }
+
+ return mp_const_none;
+}
+MP_DEFINE_CONST_FUN_OBJ_KW(busio_i2c_readfrom_into_obj, 3, busio_i2c_readfrom_into);
+
+//| .. method:: I2C.writeto(address, buffer, \*, start=0, end=len(buffer), stop=True)
+//|
+//| Write the bytes from ``buffer`` to the slave specified by ``address``.
+//| Transmits a stop bit if ``stop`` is set.
+//|
+//| If ``start`` or ``end`` is provided, then the buffer will be sliced
+//| as if ``buffer[start:end]``. This will not cause an allocation like
+//| ``buffer[start:end]`` will so it saves memory.
+//|
+//| :param int address: 7-bit device address
+//| :param bytearray buffer: buffer containing the bytes to write
+//| :param int start: Index to start writing from
+//| :param int end: Index to read up to but not include
+//| :param bool stop: If true, output an I2C stop condition after the
+//| buffer is written
+//|
+STATIC mp_obj_t busio_i2c_writeto(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
+ enum { ARG_address, ARG_buffer, ARG_start, ARG_end, ARG_stop };
+ static const mp_arg_t allowed_args[] = {
+ { MP_QSTR_address, MP_ARG_REQUIRED | MP_ARG_INT, {.u_int = 0} },
+ { 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} },
+ { MP_QSTR_stop, MP_ARG_KW_ONLY | MP_ARG_BOOL, {.u_bool = true} },
+ };
+ busio_i2c_obj_t *self = MP_OBJ_TO_PTR(pos_args[0]);
+ check_lock(self);
+ 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);
+
+ // get the buffer to write the data from
+ mp_buffer_info_t bufinfo;
+ mp_get_buffer_raise(args[ARG_buffer].u_obj, &bufinfo, MP_BUFFER_READ);
+
+ int32_t end = args[ARG_end].u_int;
+ if (end < 0) {
+ end += bufinfo.len;
+ }
+ uint32_t start = args[ARG_start].u_int;
+ uint32_t len = end - start;
+ if ((uint32_t) end < start) {
+ len = 0;
+ } else if (len > bufinfo.len) {
+ len = bufinfo.len;
+ }
+
+ // do the transfer
+ uint8_t status = common_hal_busio_i2c_write(self, args[ARG_address].u_int,
+ ((uint8_t*) bufinfo.buf) + start, len, args[ARG_stop].u_bool);
+ if (status != 0) {
+ mp_raise_OSError(status);
+ }
+ return mp_const_none;
+}
+STATIC MP_DEFINE_CONST_FUN_OBJ_KW(busio_i2c_writeto_obj, 1, busio_i2c_writeto);
+
+STATIC const mp_rom_map_elem_t busio_i2c_locals_dict_table[] = {
+ { MP_ROM_QSTR(MP_QSTR_deinit), MP_ROM_PTR(&busio_i2c_deinit_obj) },
+ { MP_ROM_QSTR(MP_QSTR___enter__), MP_ROM_PTR(&default___enter___obj) },
+ { MP_ROM_QSTR(MP_QSTR___exit__), MP_ROM_PTR(&busio_i2c___exit___obj) },
+ { MP_ROM_QSTR(MP_QSTR_scan), MP_ROM_PTR(&busio_i2c_scan_obj) },
+
+ { MP_ROM_QSTR(MP_QSTR_try_lock), MP_ROM_PTR(&busio_i2c_try_lock_obj) },
+ { MP_ROM_QSTR(MP_QSTR_unlock), MP_ROM_PTR(&busio_i2c_unlock_obj) },
+
+ { MP_ROM_QSTR(MP_QSTR_readfrom_into), MP_ROM_PTR(&busio_i2c_readfrom_into_obj) },
+ { MP_ROM_QSTR(MP_QSTR_writeto), MP_ROM_PTR(&busio_i2c_writeto_obj) },
+};
+
+STATIC MP_DEFINE_CONST_DICT(busio_i2c_locals_dict, busio_i2c_locals_dict_table);
+
+const mp_obj_type_t busio_i2c_type = {
+ { &mp_type_type },
+ .name = MP_QSTR_I2C,
+ .make_new = busio_i2c_make_new,
+ .locals_dict = (mp_obj_dict_t*)&busio_i2c_locals_dict,
+};
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