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Diff: targets/TARGET_STM/TARGET_STM32F7/i2c_api.c
- Revision:
- 149:156823d33999
- Parent:
- 144:ef7eb2e8f9f7
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/targets/TARGET_STM/TARGET_STM32F7/i2c_api.c Fri Oct 28 11:17:30 2016 +0100 @@ -0,0 +1,443 @@ +/* mbed Microcontroller Library + ******************************************************************************* + * Copyright (c) 2015, STMicroelectronics + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * 1. Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright notice, + * this list of conditions and the following disclaimer in the documentation + * and/or other materials provided with the distribution. + * 3. Neither the name of STMicroelectronics nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE + * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR + * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER + * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, + * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + ******************************************************************************* + */ +#include "mbed_assert.h" +#include "i2c_api.h" + +#if DEVICE_I2C + +#include "cmsis.h" +#include "pinmap.h" +#include "PeripheralPins.h" +#include "mbed_error.h" + +/* Timeout values for flags and events waiting loops. These timeouts are + not based on accurate values, they just guarantee that the application will + not remain stuck if the I2C communication is corrupted. */ +#define FLAG_TIMEOUT ((int)0x4000) +#define LONG_TIMEOUT ((int)0x8000) + +I2C_HandleTypeDef I2cHandle; + +int i2c1_inited = 0; +int i2c2_inited = 0; +int i2c3_inited = 0; +int i2c4_inited = 0; + + +void i2c_init(i2c_t *obj, PinName sda, PinName scl) +{ + // Determine the I2C to use + I2CName i2c_sda = (I2CName)pinmap_peripheral(sda, PinMap_I2C_SDA); + I2CName i2c_scl = (I2CName)pinmap_peripheral(scl, PinMap_I2C_SCL); + + obj->i2c = (I2CName)pinmap_merge(i2c_sda, i2c_scl); + MBED_ASSERT(obj->i2c != (I2CName)NC); + + // Enable I2C clock and pinout if not done + if ((obj->i2c == I2C_1) && !i2c1_inited) { + i2c1_inited = 1; + __HAL_RCC_I2C1_CONFIG(RCC_I2C1CLKSOURCE_PCLK1); + __HAL_RCC_I2C1_CLK_ENABLE(); + // Configure I2C1 pins + pinmap_pinout(sda, PinMap_I2C_SDA); + pinmap_pinout(scl, PinMap_I2C_SCL); + pin_mode(sda, OpenDrain); + pin_mode(scl, OpenDrain); + } + + #if defined(I2C2_BASE) + if ((obj->i2c == I2C_2) && !i2c2_inited) { + i2c2_inited = 1; + __HAL_RCC_I2C2_CONFIG(RCC_I2C2CLKSOURCE_PCLK1); + __HAL_RCC_I2C2_CLK_ENABLE(); + // Configure I2C2 pins + pinmap_pinout(sda, PinMap_I2C_SDA); + pinmap_pinout(scl, PinMap_I2C_SCL); + pin_mode(sda, OpenDrain); + pin_mode(scl, OpenDrain); + } + #endif + + #if defined(I2C3_BASE) + if ((obj->i2c == I2C_3) && !i2c3_inited) { + i2c3_inited = 1; + __HAL_RCC_I2C3_CONFIG(RCC_I2C3CLKSOURCE_PCLK1); + __HAL_RCC_I2C3_CLK_ENABLE(); + // Configure I2C3 pins + pinmap_pinout(sda, PinMap_I2C_SDA); + pinmap_pinout(scl, PinMap_I2C_SCL); + pin_mode(sda, OpenDrain); + pin_mode(scl, OpenDrain); + } + #endif + + #if defined(I2C4_BASE) + if ((obj->i2c == I2C_4) && !i2c4_inited) { + i2c4_inited = 1; + __HAL_RCC_I2C4_CONFIG(RCC_I2C4CLKSOURCE_PCLK1); + __HAL_RCC_I2C4_CLK_ENABLE(); + // Configure I2C4 pins + pinmap_pinout(sda, PinMap_I2C_SDA); + pinmap_pinout(scl, PinMap_I2C_SCL); + pin_mode(sda, OpenDrain); + pin_mode(scl, OpenDrain); + } + #endif + + // Reset to clear pending flags if any + i2c_reset(obj); + + // I2C configuration + i2c_frequency(obj, 100000); // 100 kHz per default +} + +void i2c_frequency(i2c_t *obj, int hz) +{ + uint32_t tim = 0; + + MBED_ASSERT((hz == 100000) || (hz == 400000) || (hz == 1000000)); + + I2cHandle.Instance = (I2C_TypeDef *)(obj->i2c); + int timeout; + + // wait before init + timeout = LONG_TIMEOUT; + while ((__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_BUSY)) && (timeout-- != 0)) {} + + /* + Values calculated with I2C_Timing_Configuration tool (excel file) + * Standard mode (up to 100 kHz) + * Fast Mode (up to 400 kHz) + * Fast Mode Plus (up to 1 MHz) + Below values obtained with: + - I2Cx clock source = APB1CLK = 54 MHz + - Analog filter delay = ON + - Digital filter coefficient = 0 + */ + switch (hz) { + case 100000: + tim = 0x10916998; // Standard mode with Rise time = 120ns, Fall time = 120ns + break; + case 400000: + tim = 0x00B11B54; // Fast Mode with Rise time = 120ns, Fall time = 120ns + break; + case 1000000: + tim = 0x0090091B; // Fast Mode Plus with Rise time = 120ns, Fall time = 10ns + break; + default: + break; + } + + // I2C configuration + I2cHandle.Init.Timing = tim; + I2cHandle.Init.AddressingMode = I2C_ADDRESSINGMODE_7BIT; + I2cHandle.Init.DualAddressMode = I2C_DUALADDRESS_DISABLE; + I2cHandle.Init.GeneralCallMode = I2C_GENERALCALL_DISABLE; + I2cHandle.Init.NoStretchMode = I2C_NOSTRETCH_DISABLE; + I2cHandle.Init.OwnAddress1 = 0; + I2cHandle.Init.OwnAddress2 = 0; + I2cHandle.Init.OwnAddress2Masks = I2C_OA2_NOMASK; + + if (HAL_I2C_Init(&I2cHandle) != HAL_OK) { + error("Cannot initialize I2C"); + } +} + +inline int i2c_start(i2c_t *obj) +{ + I2C_TypeDef *i2c = (I2C_TypeDef *)(obj->i2c); + int timeout; + + I2cHandle.Instance = (I2C_TypeDef *)(obj->i2c); + + // Clear Acknowledge failure flag + __HAL_I2C_CLEAR_FLAG(&I2cHandle, I2C_FLAG_AF); + + // Wait the STOP condition has been previously correctly sent + timeout = FLAG_TIMEOUT; + while ((i2c->CR2 & I2C_CR2_STOP) == I2C_CR2_STOP){ + if ((timeout--) == 0) { + return 1; + } + } + + // Generate the START condition + i2c->CR2 |= I2C_CR2_START; + + // Wait the START condition has been correctly sent + timeout = FLAG_TIMEOUT; + while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_BUSY) == RESET) { + if ((timeout--) == 0) { + return 1; + } + } + + return 0; +} + +inline int i2c_stop(i2c_t *obj) +{ + I2C_TypeDef *i2c = (I2C_TypeDef *)(obj->i2c); + + // Generate the STOP condition + i2c->CR2 |= I2C_CR2_STOP; + + return 0; +} + +int i2c_read(i2c_t *obj, int address, char *data, int length, int stop) +{ + I2C_TypeDef *i2c = (I2C_TypeDef *)(obj->i2c); + I2cHandle.Instance = (I2C_TypeDef *)(obj->i2c); + int timeout; + int count; + int value; + + /* update CR2 register */ + i2c->CR2 = (i2c->CR2 & (uint32_t)~((uint32_t)(I2C_CR2_SADD | I2C_CR2_NBYTES | I2C_CR2_RELOAD | I2C_CR2_AUTOEND | I2C_CR2_RD_WRN | I2C_CR2_START | I2C_CR2_STOP))) + | (uint32_t)(((uint32_t)address & I2C_CR2_SADD) | (((uint32_t)length << 16) & I2C_CR2_NBYTES) | (uint32_t)I2C_SOFTEND_MODE | (uint32_t)I2C_GENERATE_START_READ); + + // Read all bytes + for (count = 0; count < length; count++) { + value = i2c_byte_read(obj, 0); + data[count] = (char)value; + } + + // Wait transfer complete + timeout = LONG_TIMEOUT; + while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_TC) == RESET) { + timeout--; + if (timeout == 0) { + return -1; + } + } + + __HAL_I2C_CLEAR_FLAG(&I2cHandle, I2C_FLAG_TC); + + // If not repeated start, send stop. + if (stop) { + i2c_stop(obj); + /* Wait until STOPF flag is set */ + timeout = FLAG_TIMEOUT; + while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_STOPF) == RESET) { + timeout--; + if (timeout == 0) { + return -1; + } + } + /* Clear STOP Flag */ + __HAL_I2C_CLEAR_FLAG(&I2cHandle, I2C_FLAG_STOPF); + } + + return length; +} + +int i2c_write(i2c_t *obj, int address, const char *data, int length, int stop) +{ + I2C_TypeDef *i2c = (I2C_TypeDef *)(obj->i2c); + I2cHandle.Instance = (I2C_TypeDef *)(obj->i2c); + int timeout; + int count; + + /* update CR2 register */ + i2c->CR2 = (i2c->CR2 & (uint32_t)~((uint32_t)(I2C_CR2_SADD | I2C_CR2_NBYTES | I2C_CR2_RELOAD | I2C_CR2_AUTOEND | I2C_CR2_RD_WRN | I2C_CR2_START | I2C_CR2_STOP))) + | (uint32_t)(((uint32_t)address & I2C_CR2_SADD) | (((uint32_t)length << 16) & I2C_CR2_NBYTES) | (uint32_t)I2C_SOFTEND_MODE | (uint32_t)I2C_GENERATE_START_WRITE); + + for (count = 0; count < length; count++) { + i2c_byte_write(obj, data[count]); + } + + // Wait transfer complete + timeout = FLAG_TIMEOUT; + while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_TC) == RESET) { + timeout--; + if (timeout == 0) { + return -1; + } + } + + __HAL_I2C_CLEAR_FLAG(&I2cHandle, I2C_FLAG_TC); + + // If not repeated start, send stop. + if (stop) { + i2c_stop(obj); + /* Wait until STOPF flag is set */ + timeout = FLAG_TIMEOUT; + while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_STOPF) == RESET) { + timeout--; + if (timeout == 0) { + return -1; + } + } + /* Clear STOP Flag */ + __HAL_I2C_CLEAR_FLAG(&I2cHandle, I2C_FLAG_STOPF); + } + + return count; +} + +int i2c_byte_read(i2c_t *obj, int last) +{ + I2C_TypeDef *i2c = (I2C_TypeDef *)(obj->i2c); + int timeout; + + // Wait until the byte is received + timeout = FLAG_TIMEOUT; + while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_RXNE) == RESET) { + if ((timeout--) == 0) { + return -1; + } + } + + return (int)i2c->RXDR; +} + +int i2c_byte_write(i2c_t *obj, int data) +{ + I2C_TypeDef *i2c = (I2C_TypeDef *)(obj->i2c); + int timeout; + + // Wait until the previous byte is transmitted + timeout = FLAG_TIMEOUT; + while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_TXIS) == RESET) { + if ((timeout--) == 0) { + return 0; + } + } + + i2c->TXDR = (uint8_t)data; + + return 1; +} + +void i2c_reset(i2c_t *obj) +{ + int timeout; + + // wait before reset + timeout = LONG_TIMEOUT; + while ((__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_BUSY)) && (timeout-- != 0)); + + __I2C1_FORCE_RESET(); + __I2C1_RELEASE_RESET(); +} + +#if DEVICE_I2CSLAVE + +void i2c_slave_address(i2c_t *obj, int idx, uint32_t address, uint32_t mask) +{ + I2C_TypeDef *i2c = (I2C_TypeDef *)(obj->i2c); + uint16_t tmpreg; + + // disable + i2c->OAR1 &= (uint32_t)(~I2C_OAR1_OA1EN); + // Get the old register value + tmpreg = i2c->OAR1; + // Reset address bits + tmpreg &= 0xFC00; + // Set new address + tmpreg |= (uint16_t)((uint16_t)address & (uint16_t)0x00FE); // 7-bits + // Store the new register value + i2c->OAR1 = tmpreg; + // enable + i2c->OAR1 |= I2C_OAR1_OA1EN; +} + +void i2c_slave_mode(i2c_t *obj, int enable_slave) +{ + + I2C_TypeDef *i2c = (I2C_TypeDef *)(obj->i2c); + uint16_t tmpreg; + + // Get the old register value + tmpreg = i2c->OAR1; + + // Enable / disable slave + if (enable_slave == 1) { + tmpreg |= I2C_OAR1_OA1EN; + } else { + tmpreg &= (uint32_t)(~I2C_OAR1_OA1EN); + } + + // Set new mode + i2c->OAR1 = tmpreg; + +} + +// See I2CSlave.h +#define NoData 0 // the slave has not been addressed +#define ReadAddressed 1 // the master has requested a read from this slave (slave = transmitter) +#define WriteGeneral 2 // the master is writing to all slave +#define WriteAddressed 3 // the master is writing to this slave (slave = receiver) + +int i2c_slave_receive(i2c_t *obj) +{ + I2cHandle.Instance = (I2C_TypeDef *)(obj->i2c); + int retValue = NoData; + + if (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_BUSY) == 1) { + if (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_ADDR) == 1) { + if (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_DIR) == 1) + retValue = ReadAddressed; + else + retValue = WriteAddressed; + __HAL_I2C_CLEAR_FLAG(&I2cHandle, I2C_FLAG_ADDR); + } + } + + return (retValue); +} + +int i2c_slave_read(i2c_t *obj, char *data, int length) +{ + char size = 0; + + while (size < length) data[size++] = (char)i2c_byte_read(obj, 0); + + return size; +} + +int i2c_slave_write(i2c_t *obj, const char *data, int length) +{ + char size = 0; + I2cHandle.Instance = (I2C_TypeDef *)(obj->i2c); + + do { + i2c_byte_write(obj, data[size]); + size++; + } while (size < length); + + return size; +} + + +#endif // DEVICE_I2CSLAVE + +#endif // DEVICE_I2C