ports/esp32/machine_i2c.c - lite/micropython - Linaro Git Browser

 /*
  * This file is part of the MicroPython project, http://micropython.org/
  *
  * The MIT License (MIT)
  *
  * Copyright (c) 2019 Damien P. George
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
  *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */

 #include "py/runtime.h"
 #include "py/mphal.h"
 #include "py/mperrno.h"
 #include "extmod/modmachine.h"

 #include "driver/i2c.h"
 #include "hal/i2c_ll.h"

 #if MICROPY_PY_MACHINE_I2C || MICROPY_PY_MACHINE_SOFTI2C

 #ifndef MICROPY_HW_I2C0_SCL
 #if CONFIG_IDF_TARGET_ESP32C3 || CONFIG_IDF_TARGET_ESP32S3
 #define MICROPY_HW_I2C0_SCL (GPIO_NUM_9)
 #define MICROPY_HW_I2C0_SDA (GPIO_NUM_8)
 #else
 #define MICROPY_HW_I2C0_SCL (GPIO_NUM_18)
 #define MICROPY_HW_I2C0_SDA (GPIO_NUM_19)
 #endif
 #endif

 #ifndef MICROPY_HW_I2C1_SCL
 #if CONFIG_IDF_TARGET_ESP32
 #define MICROPY_HW_I2C1_SCL (GPIO_NUM_25)
 #define MICROPY_HW_I2C1_SDA (GPIO_NUM_26)
 #else
 #define MICROPY_HW_I2C1_SCL (GPIO_NUM_9)
 #define MICROPY_HW_I2C1_SDA (GPIO_NUM_8)
 #endif
 #endif

 #if SOC_I2C_SUPPORT_XTAL
 #define I2C_SCLK_FREQ XTAL_CLK_FREQ
 #elif SOC_I2C_SUPPORT_APB
 #define I2C_SCLK_FREQ APB_CLK_FREQ
 #else
 #error "unsupported I2C for ESP32 SoC variant"
 #endif

 #define I2C_DEFAULT_TIMEOUT_US (50000) // 50ms

 typedef struct _machine_hw_i2c_obj_t {
     mp_obj_base_t base;
     i2c_port_t port : 8;
     gpio_num_t scl : 8;
     gpio_num_t sda : 8;
 } machine_hw_i2c_obj_t;

 static machine_hw_i2c_obj_t machine_hw_i2c_obj[I2C_NUM_MAX];

 static void machine_hw_i2c_init(machine_hw_i2c_obj_t *self, uint32_t freq, uint32_t timeout_us, bool first_init) {
     if (!first_init) {
         i2c_driver_delete(self->port);
     }
     i2c_config_t conf = {
         .mode = I2C_MODE_MASTER,
         .sda_io_num = self->sda,
         .sda_pullup_en = GPIO_PULLUP_ENABLE,
         .scl_io_num = self->scl,
         .scl_pullup_en = GPIO_PULLUP_ENABLE,
         .master.clk_speed = freq,
     };
     i2c_param_config(self->port, &conf);
     int timeout = I2C_SCLK_FREQ / 1000000 * timeout_us;
     i2c_set_timeout(self->port, (timeout > I2C_LL_MAX_TIMEOUT) ? I2C_LL_MAX_TIMEOUT : timeout);
     i2c_driver_install(self->port, I2C_MODE_MASTER, 0, 0, 0);
 }

 int machine_hw_i2c_transfer(mp_obj_base_t *self_in, uint16_t addr, size_t n, mp_machine_i2c_buf_t *bufs, unsigned int flags) {
     machine_hw_i2c_obj_t *self = MP_OBJ_TO_PTR(self_in);

     i2c_cmd_handle_t cmd = i2c_cmd_link_create();
     int data_len = 0;

     if (flags & MP_MACHINE_I2C_FLAG_WRITE1) {
         i2c_master_start(cmd);
         i2c_master_write_byte(cmd, addr << 1, true);
         i2c_master_write(cmd, bufs->buf, bufs->len, true);
         data_len += bufs->len;
         --n;
         ++bufs;
     }

     i2c_master_start(cmd);
     i2c_master_write_byte(cmd, addr << 1 | (flags & MP_MACHINE_I2C_FLAG_READ), true);

     for (; n--; ++bufs) {
         if (flags & MP_MACHINE_I2C_FLAG_READ) {
             i2c_master_read(cmd, bufs->buf, bufs->len, n == 0 ? I2C_MASTER_LAST_NACK : I2C_MASTER_ACK);
         } else {
             if (bufs->len != 0) {
                 i2c_master_write(cmd, bufs->buf, bufs->len, true);
             }
         }
         data_len += bufs->len;
     }

     if (flags & MP_MACHINE_I2C_FLAG_STOP) {
         i2c_master_stop(cmd);
     }

     // TODO proper timeout
     esp_err_t err = i2c_master_cmd_begin(self->port, cmd, 100 * (1 + data_len) / portTICK_PERIOD_MS);
     i2c_cmd_link_delete(cmd);

     if (err == ESP_FAIL) {
         return -MP_ENODEV;
     } else if (err == ESP_ERR_TIMEOUT) {
         return -MP_ETIMEDOUT;
     } else if (err != ESP_OK) {
         return -abs(err);
     }

     return data_len;
 }

 /******************************************************************************/
 // MicroPython bindings for machine API

 static void machine_hw_i2c_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
     machine_hw_i2c_obj_t *self = MP_OBJ_TO_PTR(self_in);
     int h, l;
     i2c_get_period(self->port, &h, &l);
     mp_printf(print, "I2C(%u, scl=%u, sda=%u, freq=%u)",
         self->port, self->scl, self->sda, I2C_SCLK_FREQ / (h + l));
 }

 mp_obj_t machine_hw_i2c_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *all_args) {
     // Create a SoftI2C instance if no id is specified (or is -1) but other arguments are given
     if (n_args != 0) {
         MP_MACHINE_I2C_CHECK_FOR_LEGACY_SOFTI2C_CONSTRUCTION(n_args, n_kw, all_args);
     }

     // Parse args
     enum { ARG_id, ARG_scl, ARG_sda, ARG_freq, ARG_timeout };
     static const mp_arg_t allowed_args[] = {
         { MP_QSTR_id, MP_ARG_INT, {.u_int = I2C_NUM_0} },
         { MP_QSTR_scl, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
         { MP_QSTR_sda, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
         { MP_QSTR_freq, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 400000} },
         { MP_QSTR_timeout, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = I2C_DEFAULT_TIMEOUT_US} },
     };
     mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
     mp_arg_parse_all_kw_array(n_args, n_kw, all_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);

     // Get I2C bus
     mp_int_t i2c_id = args[ARG_id].u_int;

     // Check if the I2C bus is valid
     if (!(I2C_NUM_0 <= i2c_id && i2c_id < I2C_NUM_MAX)) {
         mp_raise_msg_varg(&mp_type_ValueError, MP_ERROR_TEXT("I2C(%d) doesn't exist"), i2c_id);
     }

     // Get static peripheral object
     machine_hw_i2c_obj_t *self = (machine_hw_i2c_obj_t *)&machine_hw_i2c_obj[i2c_id];

     bool first_init = false;
     if (self->base.type == NULL) {
         // Created for the first time, set default pins
         self->base.type = &machine_i2c_type;
         self->port = i2c_id;
         if (self->port == I2C_NUM_0) {
             self->scl = MICROPY_HW_I2C0_SCL;
             self->sda = MICROPY_HW_I2C0_SDA;
         } else {
             self->scl = MICROPY_HW_I2C1_SCL;
             self->sda = MICROPY_HW_I2C1_SDA;
         }
         first_init = true;
     }

     // Set SCL/SDA pins if given
     if (args[ARG_scl].u_obj != MP_OBJ_NULL) {
         self->scl = machine_pin_get_id(args[ARG_scl].u_obj);
     }
     if (args[ARG_sda].u_obj != MP_OBJ_NULL) {
         self->sda = machine_pin_get_id(args[ARG_sda].u_obj);
     }

     // Initialise the I2C peripheral
     machine_hw_i2c_init(self, args[ARG_freq].u_int, args[ARG_timeout].u_int, first_init);

     return MP_OBJ_FROM_PTR(self);
 }

 static const mp_machine_i2c_p_t machine_hw_i2c_p = {
     .transfer_supports_write1 = true,
     .transfer = machine_hw_i2c_transfer,
 };

 MP_DEFINE_CONST_OBJ_TYPE(
     machine_i2c_type,
     MP_QSTR_I2C,
     MP_TYPE_FLAG_NONE,
     make_new, machine_hw_i2c_make_new,
     print, machine_hw_i2c_print,
     protocol, &machine_hw_i2c_p,
     locals_dict, &mp_machine_i2c_locals_dict
     );

 #endif
	/*
	* This file is part of the MicroPython project, http://micropython.org/
	*
	* The MIT License (MIT)
	*
	* Copyright (c) 2019 Damien P. George
	*
	* Permission is hereby granted, free of charge, to any person obtaining a copy
	* of this software and associated documentation files (the "Software"), to deal
	* in the Software without restriction, including without limitation the rights
	* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
	* copies of the Software, and to permit persons to whom the Software is
	* furnished to do so, subject to the following conditions:
	*
	* The above copyright notice and this permission notice shall be included in
	* all copies or substantial portions of the Software.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
	* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
	* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
	* THE SOFTWARE.
	*/

	#include "py/runtime.h"
	#include "py/mphal.h"
	#include "py/mperrno.h"
	#include "extmod/modmachine.h"

	#include "driver/i2c.h"
	#include "hal/i2c_ll.h"

	#if MICROPY_PY_MACHINE_I2C \|\| MICROPY_PY_MACHINE_SOFTI2C

	#ifndef MICROPY_HW_I2C0_SCL
	#if CONFIG_IDF_TARGET_ESP32C3 \|\| CONFIG_IDF_TARGET_ESP32S3
	#define MICROPY_HW_I2C0_SCL (GPIO_NUM_9)
	#define MICROPY_HW_I2C0_SDA (GPIO_NUM_8)
	#else
	#define MICROPY_HW_I2C0_SCL (GPIO_NUM_18)
	#define MICROPY_HW_I2C0_SDA (GPIO_NUM_19)
	#endif
	#endif

	#ifndef MICROPY_HW_I2C1_SCL
	#if CONFIG_IDF_TARGET_ESP32
	#define MICROPY_HW_I2C1_SCL (GPIO_NUM_25)
	#define MICROPY_HW_I2C1_SDA (GPIO_NUM_26)
	#else
	#define MICROPY_HW_I2C1_SCL (GPIO_NUM_9)
	#define MICROPY_HW_I2C1_SDA (GPIO_NUM_8)
	#endif
	#endif

	#if SOC_I2C_SUPPORT_XTAL
	#define I2C_SCLK_FREQ XTAL_CLK_FREQ
	#elif SOC_I2C_SUPPORT_APB
	#define I2C_SCLK_FREQ APB_CLK_FREQ
	#else
	#error "unsupported I2C for ESP32 SoC variant"
	#endif

	#define I2C_DEFAULT_TIMEOUT_US (50000) // 50ms

	typedef struct _machine_hw_i2c_obj_t {
	mp_obj_base_t base;
	i2c_port_t port : 8;
	gpio_num_t scl : 8;
	gpio_num_t sda : 8;
	} machine_hw_i2c_obj_t;

	static machine_hw_i2c_obj_t machine_hw_i2c_obj[I2C_NUM_MAX];

	static void machine_hw_i2c_init(machine_hw_i2c_obj_t *self, uint32_t freq, uint32_t timeout_us, bool first_init) {
	if (!first_init) {
	i2c_driver_delete(self->port);
	}
	i2c_config_t conf = {
	.mode = I2C_MODE_MASTER,
	.sda_io_num = self->sda,
	.sda_pullup_en = GPIO_PULLUP_ENABLE,
	.scl_io_num = self->scl,
	.scl_pullup_en = GPIO_PULLUP_ENABLE,
	.master.clk_speed = freq,
	};
	i2c_param_config(self->port, &conf);
	int timeout = I2C_SCLK_FREQ / 1000000 * timeout_us;
	i2c_set_timeout(self->port, (timeout > I2C_LL_MAX_TIMEOUT) ? I2C_LL_MAX_TIMEOUT : timeout);
	i2c_driver_install(self->port, I2C_MODE_MASTER, 0, 0, 0);
	}

	int machine_hw_i2c_transfer(mp_obj_base_t self_in, uint16_t addr, size_t n, mp_machine_i2c_buf_t bufs, unsigned int flags) {
	machine_hw_i2c_obj_t *self = MP_OBJ_TO_PTR(self_in);

	i2c_cmd_handle_t cmd = i2c_cmd_link_create();
	int data_len = 0;

	if (flags & MP_MACHINE_I2C_FLAG_WRITE1) {
	i2c_master_start(cmd);
	i2c_master_write_byte(cmd, addr << 1, true);
	i2c_master_write(cmd, bufs->buf, bufs->len, true);
	data_len += bufs->len;
	--n;
	++bufs;
	}

	i2c_master_start(cmd);
	i2c_master_write_byte(cmd, addr << 1 \| (flags & MP_MACHINE_I2C_FLAG_READ), true);

	for (; n--; ++bufs) {
	if (flags & MP_MACHINE_I2C_FLAG_READ) {
	i2c_master_read(cmd, bufs->buf, bufs->len, n == 0 ? I2C_MASTER_LAST_NACK : I2C_MASTER_ACK);
	} else {
	if (bufs->len != 0) {
	i2c_master_write(cmd, bufs->buf, bufs->len, true);
	}
	}
	data_len += bufs->len;
	}

	if (flags & MP_MACHINE_I2C_FLAG_STOP) {
	i2c_master_stop(cmd);
	}

	// TODO proper timeout
	esp_err_t err = i2c_master_cmd_begin(self->port, cmd, 100 * (1 + data_len) / portTICK_PERIOD_MS);
	i2c_cmd_link_delete(cmd);

	if (err == ESP_FAIL) {
	return -MP_ENODEV;
	} else if (err == ESP_ERR_TIMEOUT) {
	return -MP_ETIMEDOUT;
	} else if (err != ESP_OK) {
	return -abs(err);
	}

	return data_len;
	}

	/******************************************************************************/
	// MicroPython bindings for machine API

	static void machine_hw_i2c_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
	machine_hw_i2c_obj_t *self = MP_OBJ_TO_PTR(self_in);
	int h, l;
	i2c_get_period(self->port, &h, &l);
	mp_printf(print, "I2C(%u, scl=%u, sda=%u, freq=%u)",
	self->port, self->scl, self->sda, I2C_SCLK_FREQ / (h + l));
	}

	mp_obj_t machine_hw_i2c_make_new(const mp_obj_type_t type, size_t n_args, size_t n_kw, const mp_obj_t all_args) {
	// Create a SoftI2C instance if no id is specified (or is -1) but other arguments are given
	if (n_args != 0) {
	MP_MACHINE_I2C_CHECK_FOR_LEGACY_SOFTI2C_CONSTRUCTION(n_args, n_kw, all_args);
	}

	// Parse args
	enum { ARG_id, ARG_scl, ARG_sda, ARG_freq, ARG_timeout };
	static const mp_arg_t allowed_args[] = {
	{ MP_QSTR_id, MP_ARG_INT, {.u_int = I2C_NUM_0} },
	{ MP_QSTR_scl, MP_ARG_KW_ONLY \| MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
	{ MP_QSTR_sda, MP_ARG_KW_ONLY \| MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
	{ MP_QSTR_freq, MP_ARG_KW_ONLY \| MP_ARG_INT, {.u_int = 400000} },
	{ MP_QSTR_timeout, MP_ARG_KW_ONLY \| MP_ARG_INT, {.u_int = I2C_DEFAULT_TIMEOUT_US} },
	};
	mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
	mp_arg_parse_all_kw_array(n_args, n_kw, all_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);

	// Get I2C bus
	mp_int_t i2c_id = args[ARG_id].u_int;

	// Check if the I2C bus is valid
	if (!(I2C_NUM_0 <= i2c_id && i2c_id < I2C_NUM_MAX)) {
	mp_raise_msg_varg(&mp_type_ValueError, MP_ERROR_TEXT("I2C(%d) doesn't exist"), i2c_id);
	}

	// Get static peripheral object
	machine_hw_i2c_obj_t self = (machine_hw_i2c_obj_t )&machine_hw_i2c_obj[i2c_id];

	bool first_init = false;
	if (self->base.type == NULL) {
	// Created for the first time, set default pins
	self->base.type = &machine_i2c_type;
	self->port = i2c_id;
	if (self->port == I2C_NUM_0) {
	self->scl = MICROPY_HW_I2C0_SCL;
	self->sda = MICROPY_HW_I2C0_SDA;
	} else {
	self->scl = MICROPY_HW_I2C1_SCL;
	self->sda = MICROPY_HW_I2C1_SDA;
	}
	first_init = true;
	}

	// Set SCL/SDA pins if given
	if (args[ARG_scl].u_obj != MP_OBJ_NULL) {
	self->scl = machine_pin_get_id(args[ARG_scl].u_obj);
	}
	if (args[ARG_sda].u_obj != MP_OBJ_NULL) {
	self->sda = machine_pin_get_id(args[ARG_sda].u_obj);
	}

	// Initialise the I2C peripheral
	machine_hw_i2c_init(self, args[ARG_freq].u_int, args[ARG_timeout].u_int, first_init);

	return MP_OBJ_FROM_PTR(self);
	}

	static const mp_machine_i2c_p_t machine_hw_i2c_p = {
	.transfer_supports_write1 = true,
	.transfer = machine_hw_i2c_transfer,
	};

	MP_DEFINE_CONST_OBJ_TYPE(
	machine_i2c_type,
	MP_QSTR_I2C,
	MP_TYPE_FLAG_NONE,
	make_new, machine_hw_i2c_make_new,
	print, machine_hw_i2c_print,
	protocol, &machine_hw_i2c_p,
	locals_dict, &mp_machine_i2c_locals_dict
	);

	#endif