ardupilot/libraries/AP_HAL_F4Light/hardware/hal/i2c.c

282 lines
7.8 KiB
C

/*
(c) 2017 night_ghost@ykoctpa.ru
based on: datasheet
*/
#pragma GCC optimize ("O2")
#include "i2c.h"
#include "dma.h"
#include "systick.h"
#include "stm32f4xx_i2c.h"
#include "stm32f4xx_dma.h"
static i2c_state i2c1_state IN_CCM;
static i2c_state i2c2_state IN_CCM;
static const i2c_dev i2c_dev1 = {
.I2Cx = I2C1,
.gpio_port = &gpiob,
.sda_pin = 9,
.scl_pin = 8,
.clk = RCC_APB1Periph_I2C1,
.gpio_af = GPIO_AF_I2C1,
.ev_nvic_line = I2C1_EV_IRQn,
.er_nvic_line = I2C1_ER_IRQn,
// .dma = { DMA_CR_CH1, DMA1_STREAM0, DMA1_STREAM6 }, // I2C1
.state = &i2c1_state,
};
/** I2C1 device */
const i2c_dev* const _I2C1 = &i2c_dev1;
static const i2c_dev i2c_dev2 = {
.I2Cx = I2C2,
.gpio_port = &gpiob,
.sda_pin = 11,
.scl_pin = 10,
.clk = RCC_APB1Periph_I2C2,
.gpio_af = GPIO_AF_I2C2,
.ev_nvic_line = I2C2_EV_IRQn,
.er_nvic_line = I2C2_ER_IRQn,
// .dma = { DMA_CR_CH7, DMA1_STREAM3 /* intersects with spi2_tx */ , DMA1_STREAM7 }, // I2C2
.state = &i2c2_state,
};
/** I2C2 device */
const i2c_dev* const _I2C2 = &i2c_dev2;
typedef enum {TX = 0, RX = 1, TXREG = 2} I2C_Dir;
static void delay_10us(){
hal_delay_microseconds(10);
}
uint32_t i2c_bit_time=4;
/**
* @brief DeInitializes peripherals used by the I2C driver.
* @param None
* @retval None
*/
void i2c_lowLevel_deinit(const i2c_dev *dev){
GPIO_InitTypeDef GPIO_InitStructure;
/* I2C Peripheral Disable */
I2C_Cmd(dev->I2Cx, DISABLE);
/* I2C DeInit */
I2C_DeInit(dev->I2Cx);
/*!< GPIO configuration */
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz; // low speed to prevent glitches
/*!< Configure I2C pins: SCL */
GPIO_InitStructure.GPIO_Pin = BIT(dev->scl_pin);
GPIO_Init(dev->gpio_port->GPIOx, &GPIO_InitStructure);
/*!< Configure I2C pins: SDA */
GPIO_InitStructure.GPIO_Pin = BIT(dev->sda_pin);
GPIO_Init(dev->gpio_port->GPIOx, &GPIO_InitStructure);
}
/**
* @brief Initializes peripherals used by the I2C driver.
*/
static inline void i2c_lowLevel_init(const i2c_dev *dev) {
memset(dev->state,0,sizeof(i2c_state));
GPIO_InitTypeDef GPIO_InitStructure;
/* Enable the i2c */
RCC_APB1PeriphClockCmd(dev->clk, ENABLE);
/* Reset the Peripheral */
RCC_APB1PeriphResetCmd(dev->clk, ENABLE);
RCC_APB1PeriphResetCmd(dev->clk, DISABLE);
/* Enable the GPIOs for the SCL/SDA Pins */
RCC_AHB1PeriphClockCmd(dev->gpio_port->clk, ENABLE);
memset(dev->state,0,sizeof(i2c_state));
// common configuration
/* common GPIO configuration */
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_25MHz; // GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_OType = GPIO_OType_OD;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;
/* Configure SCL */
GPIO_InitStructure.GPIO_Pin = BIT(dev->scl_pin);
GPIO_Init(dev->gpio_port->GPIOx, &GPIO_InitStructure);
/* Configure SDA */
GPIO_InitStructure.GPIO_Pin = BIT(dev->sda_pin);
GPIO_Init(dev->gpio_port->GPIOx, &GPIO_InitStructure);
/* Connect GPIO pins to peripheral, SCL must be first! */
gpio_set_af_mode(dev->gpio_port, dev->scl_pin, dev->gpio_af);
gpio_set_af_mode(dev->gpio_port, dev->sda_pin, dev->gpio_af);
}
void i2c_init(const i2c_dev *dev, uint16_t address, uint32_t speed)
{
i2c_lowLevel_init(dev); // init GPIO hardware
i2c_bit_time = 1000000l / speed;
I2C_InitTypeDef I2C_InitStructure; /* I2C configuration */
I2C_StructInit(&I2C_InitStructure);
I2C_InitStructure.I2C_Mode = I2C_Mode_I2C;
I2C_InitStructure.I2C_DutyCycle = I2C_DutyCycle_2;
I2C_InitStructure.I2C_OwnAddress1 = address;
I2C_InitStructure.I2C_Ack = I2C_Ack_Enable;
I2C_InitStructure.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit;
I2C_InitStructure.I2C_ClockSpeed = speed;
I2C_ITConfig(dev->I2Cx, I2C_IT_EVT | I2C_IT_BUF | I2C_IT_ERR, DISABLE);
(void)dev->I2Cx->DR;
/* I2C Peripheral Enable */
I2C_Cmd(dev->I2Cx, ENABLE);
/* Apply I2C configuration after enabling it */
I2C_Init(dev->I2Cx, &I2C_InitStructure);
}
/**
* @brief DeInitializes peripherals used by the I2C driver.
* @param None
* @retval None
*/
void i2c_deinit(const i2c_dev *dev)
{
i2c_lowLevel_deinit(dev);
}
static void ev_handler(const i2c_dev *dev, bool err){
if(dev->state->handler) revo_call_handler(dev->state->handler, err);
else { // disable interrupts
dev->I2Cx->CR2 &= ~(I2C_CR2_ITBUFEN|I2C_CR2_ITEVTEN|I2C_CR2_ITERREN); // Disable interrupts
}
}
void I2C1_EV_IRQHandler(); // to avoid warnings
void I2C1_ER_IRQHandler();
void I2C2_EV_IRQHandler();
void I2C2_ER_IRQHandler();
void I2C1_EV_IRQHandler(){ // I2C1 Event
ev_handler(_I2C1, false);
}
void I2C1_ER_IRQHandler(){ // I2C1 Error
ev_handler(_I2C1, true);
}
void I2C2_EV_IRQHandler(){ // I2C2 Event
ev_handler(_I2C2, false);
}
void I2C2_ER_IRQHandler(){ // I2C2 Error
ev_handler(_I2C2, true);
}
void i2c_master_release_bus(const i2c_dev *dev) {
gpio_write_bit(dev->gpio_port, dev->scl_pin, 1);
gpio_write_bit(dev->gpio_port, dev->sda_pin, 1);
gpio_set_mode(dev->gpio_port, dev->scl_pin, GPIO_OUTPUT_OD_PU);
gpio_set_mode(dev->gpio_port, dev->sda_pin, GPIO_OUTPUT_OD_PU);
}
/**
* @brief Reset an I2C bus.
*
* Reset is accomplished by clocking out pulses until any hung slaves
* release SDA and SCL, then generating a START condition, then a STOP
* condition.
*
* @param dev I2C device
*/
#define MAX_I2C_TIME 300 // 300ms before device turn off
bool i2c_bus_reset(const i2c_dev *dev) {
/* Release both lines */
i2c_master_release_bus(dev);
uint32_t t=systick_uptime();
/*
* Make sure the bus is free by clocking it until any slaves release the
* bus.
*/
again:
/* Wait for any clock stretching to finish */
while (!gpio_read_bit(dev->gpio_port, dev->scl_pin)) {// device can output 1 so check clock first
if(systick_uptime()-t > MAX_I2C_TIME) return false;
hal_yield(10);
}
delay_10us(); // 50kHz
while (!gpio_read_bit(dev->gpio_port, dev->sda_pin)) {
/* Wait for any clock stretching to finish */
while (!gpio_read_bit(dev->gpio_port, dev->scl_pin)){
if(systick_uptime()-t > MAX_I2C_TIME) return false;
hal_yield(10);
}
delay_10us(); // 50kHz
/* Pull low */
gpio_write_bit(dev->gpio_port, dev->scl_pin, 0);
delay_10us();
/* Release high again */
gpio_write_bit(dev->gpio_port, dev->scl_pin, 1);
delay_10us();
}
/* Generate start then stop condition */
gpio_write_bit(dev->gpio_port, dev->sda_pin, 0);
delay_10us();
gpio_write_bit(dev->gpio_port, dev->scl_pin, 0);
delay_10us();
gpio_write_bit(dev->gpio_port, dev->scl_pin, 1);
delay_10us();
gpio_write_bit(dev->gpio_port, dev->sda_pin, 1);
uint32_t rtime = stopwatch_getticks();
uint32_t dt = us_ticks * 50; // 50uS
while ((stopwatch_getticks() - rtime) < dt) {
if (!gpio_read_bit(dev->gpio_port, dev->scl_pin)) goto again; // any SCL activity after STOP
}
// we was generating signals on I2C bus, but BUSY flag senses it even when hardware is off
// datasheet: It indicates a communication in progress on the bus. This information is still updated when the interface is disabled (PE=0).
dev->I2Cx->CR1 |= I2C_CR1_SWRST; // set SoftReset for some time
hal_yield(0);
dev->I2Cx->CR1 &= (uint16_t)(~I2C_CR1_SWRST); // clear SoftReset flag
return true;
}