From 29a25e0425b19a292ca8458cc7aade6a02a0d921 Mon Sep 17 00:00:00 2001
From: lilian <lilian@CETS01.lan>
Date: Fri, 26 Aug 2016 10:31:25 +0200
Subject: [PATCH] new i2c
---
extras/fast_i2c/component.mk | 10 +++
extras/fast_i2c/i2c.c | 161 +++++++++++++++++++++++++++++++++++
extras/fast_i2c/i2c.h | 102 ++++++++++++++++++++++
3 files changed, 273 insertions(+)
create mode 100644 extras/fast_i2c/component.mk
create mode 100644 extras/fast_i2c/i2c.c
create mode 100644 extras/fast_i2c/i2c.h
diff --git a/extras/fast_i2c/component.mk b/extras/fast_i2c/component.mk
new file mode 100644
index 0000000..795c501
--- /dev/null
+++ b/extras/fast_i2c/component.mk
@@ -0,0 +1,10 @@
+# Component makefile for fast_i2c/i2c
+
+# expected anyone using i2c driver includes it as 'fast_i2c/i2c.h'
+INC_DIRS += $(i2c_ROOT)..
+
+# args for passing into compile rule generation
+i2c_INC_DIR =
+i2c_SRC_DIR = $(i2c_ROOT)
+
+$(eval $(call component_compile_rules,i2c))
diff --git a/extras/fast_i2c/i2c.c b/extras/fast_i2c/i2c.c
new file mode 100644
index 0000000..72ec26e
--- /dev/null
+++ b/extras/fast_i2c/i2c.c
@@ -0,0 +1,161 @@
+/*
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2015 Lilian Marazano (github.com/Zaltora)
+ * Based on Baoshi i2c library <mail(at)ba0sh1(dot)com>
+ *
+ * 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 "i2c.h"
+
+static uint8_t _scl_pin;
+static uint8_t _sda_pin;
+
+void i2c_init(uint8_t scl_pin, uint8_t sda_pin) {
+
+ _scl_pin = scl_pin ;
+ _sda_pin = sda_pin ;
+
+ gpio_enable(_sda_pin, GPIO_OUT_OPEN_DRAIN);
+ gpio_enable(_scl_pin, GPIO_OUT_OPEN_DRAIN);
+ // Set idle bus high
+ _SDA1;
+ _SCL1;
+
+ return;
+}
+
+uint8_t i2c_start(void) {
+
+ _SDA1;
+ _SCL1;
+ _DELAY;
+ if (_SDAX == 0) return false; // Bus busy
+ _SDA0;
+ _DELAY;
+ _SCL0;
+ return true;
+}
+
+void i2c_stop(void) {
+
+ _SDA0;
+ _SCL1;
+ _DELAY;
+ while (_SCLX == 0); // clock stretching
+ _SDA1;
+ _DELAY;
+}
+
+uint8_t i2c_write(uint8_t data) {
+
+ uint8_t ibit;
+ uint8_t ret;
+
+ for (ibit = 0; ibit < 8; ++ibit)
+ {
+ if (data & 0x80)
+ _SDA1;
+ else
+ _SDA0;
+ _DELAY;
+ _SCL1;
+ _DELAY;
+ data = data << 1;
+ _SCL0;
+ }
+ _SDA1;
+ _DELAY;
+ _SCL1;
+ _DELAY;
+ ret = (_SDAX == 0);
+ _SCL0;
+ _DELAY;
+
+ return ret;
+}
+
+uint8_t i2c_read(uint8_t ack) {
+
+ uint8_t data = 0;
+ uint8_t ibit = 8;
+
+ _SDA1;
+ while (ibit--)
+ {
+ data = data << 1;
+ _SCL0;
+ _DELAY;
+ _SCL1;
+ _DELAY;
+ if (_SDAX)
+ data = data | 0x01;
+ }
+ _SCL0;
+ if (ack)
+ _SDA0; // ACK
+ else
+ _SDA1; // NACK
+ _DELAY;
+ // Send clock
+ _SCL1;
+ _DELAY;
+ _SCL0;
+ _DELAY;
+ // ACK end
+ _SDA1;
+
+ return data;
+}
+
+bool i2c_slave_read(uint8_t slave_addr, uint8_t data, uint8_t *buf, uint16_t len) {
+
+ i2c_start();
+ if(!i2c_write(slave_addr<<1)) goto fail_send; // adress + W
+ if(!i2c_write(data)) goto fail_send; //Send byte
+ i2c_start(); // restart condition
+ if(!i2c_write((slave_addr<<1) | 1)) goto fail_send; // adress + R
+
+ while(--len) {
+ *(buf++) = i2c_read(1);
+ }
+ *buf = i2c_read(0);
+ i2c_stop();
+ return true;
+
+ fail_send:
+ i2c_stop();
+ return false ;
+}
+
+bool i2c_slave_write(uint8_t slave_addr, uint8_t *buf, uint16_t len) {
+
+ i2c_start();
+ if(!i2c_write(slave_addr<<1)) goto fail_send ; // adress + W
+ while (len--) {
+ if(!i2c_write((uint8_t) *(buf++))) goto fail_send ;
+ }
+ i2c_stop();
+ return true;
+
+ fail_send:
+ i2c_stop();
+ return false ;
+}
diff --git a/extras/fast_i2c/i2c.h b/extras/fast_i2c/i2c.h
new file mode 100644
index 0000000..b9f54b4
--- /dev/null
+++ b/extras/fast_i2c/i2c.h
@@ -0,0 +1,102 @@
+/*
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2015 Lilian Marazano (github.com/Zaltora)
+ * Based on Baoshi i2c library <mail(at)ba0sh1(dot)com>
+ *
+ * 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 __I2C_H__
+#define __I2C_H__
+#endif
+
+#include <esp8266.h>
+#include <espressif/esp_misc.h> // sdk_os_delay_us
+#include <stdint.h>
+#include <stdbool.h>
+
+
+//#define _DELAY sdk_os_delay_us(1) // can up to 300kHz max
+#define _DELAY for (volatile uint32_t __j = 3; __j > 0; __j--) // can up to 1.9MHz max at 160MHz clock
+
+// if you want use an other API for GPIO or use GPIO16, change here
+#define _SDA1 gpio_write(_sda_pin, 1)
+#define _SDA0 gpio_write(_sda_pin, 0)
+
+#define _SCL1 gpio_write(_scl_pin, 1)
+#define _SCL0 gpio_write(_scl_pin, 0)
+
+#define _SDAX gpio_read(_sda_pin)
+#define _SCLX gpio_read(_scl_pin)
+
+
+/**
+ * @brief Init I2C bus
+ * @param scl_pin SCL pin number
+ * @param sda_pin SDA pin number
+ */
+void i2c_init(uint8_t scl_pin, uint8_t sda_pin) ;
+
+/**
+ * @brief Send data to I2C bus
+ * @param data Data to send
+ * @return true if ACK is received at end of sending. False if not ACK'ed
+ */
+uint8_t i2c_write(uint8_t data);
+
+/**
+ * @brief Read data from I2C bus
+ * @param ack ACK (true) or NACK (false)
+ * @return Data read
+ */
+uint8_t i2c_read(uint8_t ack);
+
+
+
+/**
+ * @brief Send I2C start bit
+ * @return true if start successfully. Otherwise the bus is busy
+ */
+uint8_t i2c_start(void);
+
+/**
+ * @brief Send I2C stop bit
+ */
+void i2c_stop(void);
+
+/**
+ * @brief Write multiple bytes to a device.
+ * @param slave_addr I2C slave device address
+ * @param buf Buffer to copy new data from
+ * @param len Number of bytes to write
+ * @return Status of operation (true = success)
+ */
+bool i2c_slave_write(uint8_t slave_addr, uint8_t *buf, uint16_t len);
+
+/**
+ * @brief Read multiple bytes from a device register.
+ * @param slave_addr I2C slave device address
+ * @param data First register to read from
+ * @param buf Buffer to store read data in
+ * @param len Number of bytes to read
+ * @return Status of read operation (true = success)
+ */
+bool i2c_slave_read(uint8_t slave_addr, uint8_t data, uint8_t *buf, uint16_t len);
+