void i2c_set_clock_frequency(u32 i2c, u8 freq)
{
u16 reg16;
reg16 = I2C_CR2(i2c) & 0xffc0; /* Clear bits [5:0]. */
reg16 |= freq;
I2C_CR2(i2c) = reg16;
}
void i2c3_ev_isr(void) {
uint32_t i2c = (uint32_t) i2c3.reg_addr;
I2C_CR2(i2c) &= ~I2C_CR2_ITERREN;
i2c_irq(&i2c3);
i2c3_watchdog_counter = 0;
I2C_CR2(i2c) |= I2C_CR2_ITERREN;
}
void i2c1_er_isr(void) {
uint32_t i2c = (uint32_t) i2c1.reg_addr;
I2C_CR2(i2c) &= ~I2C_CR2_ITEVTEN;
i2c_irq(&i2c1);
i2c1_watchdog_counter = 0;
I2C_CR2(i2c) |= I2C_CR2_ITEVTEN;
}
static inline void PPRZ_I2C_SEND_START(struct i2c_periph *periph)
{
uint32_t i2c = (uint32_t) periph->reg_addr;
// Reset the buffer pointer to the first byte
periph->idx_buf = 0;
#ifdef I2C_DEBUG_LED
LED_SHOW_ACTIVE_BITS(regs);
LED2_ON();
LED1_ON();
LED1_OFF();
LED1_ON();
LED1_OFF();
LED1_ON();
LED1_OFF();
LED2_OFF();
#endif
// Enable Error IRQ, Event IRQ but disable Buffer IRQ
I2C_CR2(i2c) |= I2C_CR2_ITERREN;
I2C_CR2(i2c) |= I2C_CR2_ITEVTEN;
I2C_CR2(i2c) &= ~ I2C_CR2_ITBUFEN;
// Issue a new start
I2C_CR1(i2c) = (I2C_CR1_START | I2C_CR1_PE);
periph->status = I2CStartRequested;
}
// Doc ID 13902 Rev 11 p 714/1072
// Transfer Sequence Diagram for Master Receiver for N=1
static inline enum STMI2CSubTransactionStatus stmi2c_read1(uint32_t i2c, struct i2c_periph *periph, struct i2c_transaction *trans)
{
uint16_t SR1 = I2C_SR1(i2c);
// Start Condition Was Just Generated
if (BIT_X_IS_SET_IN_REG( I2C_SR1_SB, SR1 ) )
{
I2C_CR2(i2c) &= ~ I2C_CR2_ITBUFEN;
I2C_DR(i2c) = trans->slave_addr | 0x01;
// Document the current Status
periph->status = I2CAddrRdSent;
}
// Address Was Sent
else if (BIT_X_IS_SET_IN_REG(I2C_SR1_ADDR, SR1) )
{
// First Clear the ACK bit: after the next byte we do not want new bytes
I2C_CR1(i2c) &= ~ I2C_CR1_POS;
I2C_CR1(i2c) &= ~ I2C_CR1_ACK;
// --- next to steps MUST be executed together to avoid missing the stop
__I2C_REG_CRITICAL_ZONE_START;
// Only after setting ACK, read SR2 to clear the ADDR (next byte will start arriving)
uint16_t SR2 __attribute__ ((unused)) = I2C_SR2(i2c);
// Schedule a Stop
PPRZ_I2C_SEND_STOP(i2c);
__I2C_REG_CRITICAL_ZONE_STOP;
// --- end of critical zone -----------
// Enable the RXNE: it will trigger as soon as the 1 byte is received to get the result
I2C_CR2(i2c) |= I2C_CR2_ITBUFEN;
// Document the current Status
periph->status = I2CReadingLastByte;
}
// As soon as there is 1 byte ready to read, we have our byte
else if (BIT_X_IS_SET_IN_REG(I2C_SR1_RxNE, SR1) )
{
I2C_CR2(i2c) &= ~ I2C_CR2_ITBUFEN;
trans->buf[0] = I2C_DR(i2c);
// We got all the results (stop condition might still be in progress but this is the last interrupt)
trans->status = I2CTransSuccess;
// Document the current Status:
// -the stop was actually already requested in the previous step
periph->status = I2CStopRequested;
return STMI2C_SubTra_Ready_StopRequested;
}
else // Event Logic Error
{
return STMI2C_SubTra_Error;
}
return STMI2C_SubTra_Busy;
}
void i2c_set_clock_frequency(uint32_t i2c, uint8_t freq)
{
uint16_t reg16;
reg16 = I2C_CR2(i2c) & 0xffc0; /* Clear bits [5:0]. */
reg16 |= freq;
I2C_CR2(i2c) = reg16;
}
static inline void stmi2c_clear_pending_interrupts(uint32_t i2c)
{
uint16_t SR1 = I2C_SR1(i2c);
// Certainly do not wait for buffer interrupts:
// -------------------------------------------
I2C_CR2(i2c) &= ~ I2C_CR2_ITBUFEN; // Disable TXE, RXNE
// Error interrupts are handled separately:
// ---------------------------------------
// Clear Event interrupt conditions:
// --------------------------------
// Start Condition Was Generated
if (BIT_X_IS_SET_IN_REG( I2C_SR1_SB, SR1 ) )
{
// SB: cleared by software when reading SR1 and writing to DR
I2C_DR(i2c) = 0x00;
}
// Address Was Sent
if (BIT_X_IS_SET_IN_REG(I2C_SR1_ADDR, SR1) )
{
// ADDR: Cleared by software when reading SR1 and then SR2
uint16_t SR2 __attribute__ ((unused)) = I2C_SR2(i2c);
}
// Byte Transfer Finished
if (BIT_X_IS_SET_IN_REG(I2C_SR1_BTF, SR1) )
{
// SB: cleared by software when reading SR1 and reading/writing to DR
uint8_t dummy __attribute__ ((unused)) = I2C_DR(i2c);
I2C_DR(i2c) = 0x00;
}
}
void i2c2_hw_init(void) {
i2c2.reg_addr = (void *)I2C2;
i2c2.init_struct = NULL;
i2c2.errors = &i2c2_errors;
i2c2_watchdog_counter = 0;
/* zeros error counter */
ZEROS_ERR_COUNTER(i2c2_errors);
/* reset peripheral to default state ( sometimes not achieved on reset :( ) */
//i2c_reset(I2C2);
/* Configure priority grouping 0 bits for pre-emption priority and 4 bits for sub-priority. */
scb_set_priority_grouping(SCB_AIRCR_PRIGROUP_NOGROUP_SUB16);
/* Configure and enable I2C2 event interrupt --------------------------------*/
nvic_set_priority(NVIC_I2C2_EV_IRQ, 0);
nvic_enable_irq(NVIC_I2C2_EV_IRQ);
/* Configure and enable I2C2 err interrupt ----------------------------------*/
nvic_set_priority(NVIC_I2C2_ER_IRQ, 1);
nvic_enable_irq(NVIC_I2C2_ER_IRQ);
/* Enable peripheral clocks -------------------------------------------------*/
/* Enable I2C2 clock */
rcc_peripheral_enable_clock(&RCC_APB1ENR, RCC_APB1ENR_I2C2EN);
/* Enable GPIO clock */
gpio_enable_clock(I2C2_GPIO_PORT);
#if defined(STM32F1)
gpio_set_mode(I2C2_GPIO_PORT, GPIO_MODE_OUTPUT_2_MHZ,
GPIO_CNF_OUTPUT_ALTFN_OPENDRAIN,
I2C2_GPIO_SCL | I2C2_GPIO_SDA);
#elif defined(STM32F4)
gpio_mode_setup(I2C2_GPIO_PORT, GPIO_MODE_AF, GPIO_PUPD_NONE,
I2C2_GPIO_SCL | I2C2_GPIO_SDA);
gpio_set_output_options(I2C2_GPIO_PORT, GPIO_OTYPE_OD, GPIO_OSPEED_25MHZ,
I2C2_GPIO_SCL | I2C2_GPIO_SDA);
gpio_set_af(I2C2_GPIO_PORT, GPIO_AF4,
I2C2_GPIO_SCL | I2C2_GPIO_SDA);
#endif
i2c_reset(I2C2);
// enable peripheral
i2c_peripheral_enable(I2C2);
/*
* XXX: there is a function to do that already in libopencm3 but I am not
* sure if it is correct, using direct register instead (esden)
*/
//i2c_set_own_7bit_slave_address(I2C2, 0);
I2C_OAR1(I2C2) = 0 | 0x4000;
// enable error interrupts
I2C_CR2(I2C1) |= I2C_CR2_ITERREN;
i2c_setbitrate(&i2c2, I2C2_CLOCK_SPEED);
}
void i2c3_er_isr(void) {
uint32_t i2c = (uint32_t) i2c3.reg_addr;
i2c_disable_interrupt(i2c, I2C_CR2_ITEVTEN);
I2C_CR2(i2c) &= ~I2C_CR2_ITEVTEN;
i2c3.watchdog = 0; // restart watchdog
i2c_irq(&i2c3);
i2c_enable_interrupt(i2c, I2C_CR2_ITEVTEN);
}
uint8_t i2c_is_start(uint32_t i2c)
{
if ((I2C_CR2(i2c) & I2C_CR2_START) != 0) {
return 1;
}
return 0;
}
void i2c3_hw_init(void) {
i2c3.reg_addr = (void *)I2C3;
i2c3.init_struct = NULL;
i2c3.errors = &i2c3_errors;
i2c3_watchdog_counter = 0;
/* zeros error counter */
ZEROS_ERR_COUNTER(i2c3_errors);
/* reset peripheral to default state ( sometimes not achieved on reset :( ) */
//i2c_reset(I2C3);
/* Configure and enable I2C3 event interrupt --------------------------------*/
nvic_set_priority(NVIC_I2C3_EV_IRQ, NVIC_I2C3_IRQ_PRIO);
nvic_enable_irq(NVIC_I2C3_EV_IRQ);
/* Configure and enable I2C3 err interrupt ----------------------------------*/
nvic_set_priority(NVIC_I2C3_ER_IRQ, NVIC_I2C3_IRQ_PRIO+1);
nvic_enable_irq(NVIC_I2C3_ER_IRQ);
/* Enable peripheral clocks -------------------------------------------------*/
/* Enable I2C3 clock */
rcc_periph_clock_enable(RCC_I2C3);
/* Enable GPIO clock */
gpio_enable_clock(I2C3_GPIO_PORT_SCL);
gpio_mode_setup(I2C3_GPIO_PORT_SCL, GPIO_MODE_AF, GPIO_PUPD_NONE, I2C3_GPIO_SCL);
gpio_set_output_options(I2C3_GPIO_PORT_SCL, GPIO_OTYPE_OD, GPIO_OSPEED_25MHZ,
I2C3_GPIO_SCL);
gpio_set_af(I2C3_GPIO_PORT_SCL, GPIO_AF4, I2C3_GPIO_SCL);
gpio_enable_clock(I2C3_GPIO_PORT_SDA);
gpio_mode_setup(I2C3_GPIO_PORT_SDA, GPIO_MODE_AF, GPIO_PUPD_NONE, I2C3_GPIO_SDA);
gpio_set_output_options(I2C3_GPIO_PORT_SDA, GPIO_OTYPE_OD, GPIO_OSPEED_25MHZ,
I2C3_GPIO_SDA);
gpio_set_af(I2C3_GPIO_PORT_SDA, GPIO_AF4, I2C3_GPIO_SDA);
i2c_reset(I2C3);
// enable peripheral
i2c_peripheral_enable(I2C3);
/*
* XXX: there is a function to do that already in libopencm3 but I am not
* sure if it is correct, using direct register instead (esden)
*/
//i2c_set_own_7bit_slave_address(I2C3, 0);
I2C_OAR1(I2C3) = 0 | 0x4000;
// enable error interrupts
I2C_CR2(I2C1) |= I2C_CR2_ITERREN;
i2c_setbitrate(&i2c3, I2C3_CLOCK_SPEED);
}
static void init_i2c2(void) {
*RCC_APB1ENR |= RCC_APB1ENR_I2C2EN; /* Enable I2C2 Clock */
*RCC_AHB1ENR |= RCC_AHB1ENR_GPIOBEN; /* Enable GPIOB Clock */
/* Set PB8 and PB9 to alternative function I2C
* See stm32f4_ref.pdf pg 141 and stm32f407.pdf pg 51 */
/* I2C2_SCL */
gpio_moder(GPIOB, I2C2_SCL, GPIO_MODER_ALT);
gpio_afr(GPIOB, I2C2_SCL, GPIO_AF_I2C);
gpio_otyper(GPIOB, I2C2_SCL, GPIO_OTYPER_OD);
gpio_pupdr(GPIOB, I2C2_SCL, GPIO_PUPDR_NONE);
gpio_ospeedr(GPIOB, I2C2_SCL, GPIO_OSPEEDR_50M);
/* I2C2_SDA */
gpio_moder(GPIOB, I2C2_SDA, GPIO_MODER_ALT);
gpio_afr(GPIOB, I2C2_SDA, GPIO_AF_I2C);
gpio_otyper(GPIOB, I2C2_SDA, GPIO_OTYPER_OD);
gpio_pupdr(GPIOB, I2C2_SDA, GPIO_PUPDR_NONE);
gpio_ospeedr(GPIOB, I2C2_SDA, GPIO_OSPEEDR_50M);
/* Configure peripheral */
*I2C_CR2(2) |= I2C_CR2_FREQ(42);
/* Set I2C to 300kHz */
*I2C_CCR(2) |= I2C_CCR_CCR(140);
*I2C_TRISE(2) = 43;
/* Enable */
*I2C_CR1(2) |= I2C_CR1_PE;
/* Pre-initialized */
//init_semaphore(&i2c2_semaphore);
i2c2.ready = 1;
}
void i2c_set_7bit_address(uint32_t i2c, uint8_t addr)
{
I2C_CR2(i2c) = (I2C_CR2(i2c) & ~I2C_CR2_SADD_7BIT_MASK) |
((addr & 0x7F) << I2C_CR2_SADD_7BIT_SHIFT);
}
void i2c_set_10bit_addr_mode(uint32_t i2c)
{
I2C_CR2(i2c) |= I2C_CR2_ADD10;
}
void i2c_set_7bit_addr_mode(uint32_t i2c)
{
I2C_CR2(i2c) &= ~I2C_CR2_ADD10;
}
void i2c_send_stop(uint32_t i2c)
{
I2C_CR2(i2c) |= I2C_CR2_STOP;
}
/** @brief I2C Clear DMA last transfer
@param[in] i2c Unsigned int32. I2C register base address @ref i2c_reg_base.
*/
void i2c_clear_dma_last_transfer(uint32_t i2c)
{
I2C_CR2(i2c) &= ~I2C_CR2_LAST;
}
/** @brief I2C Set DMA last transfer
@param[in] i2c Unsigned int32. I2C register base address @ref i2c_reg_base.
*/
void i2c_set_dma_last_transfer(uint32_t i2c)
{
I2C_CR2(i2c) |= I2C_CR2_LAST;
}
void i2c_disable_autoend(uint32_t i2c)
{
I2C_CR2(i2c) &= ~I2C_CR2_AUTOEND;
}
/** @brief I2C Disable DMA
@param[in] i2c Unsigned int32. I2C register base address @ref i2c_reg_base.
*/
void i2c_disable_dma(u32 i2c)
{
I2C_CR2(i2c) &= ~I2C_CR2_DMAEN;
}
void i2c_set_read_transfer_dir(uint32_t i2c)
{
I2C_CR2(i2c) |= I2C_CR2_RD_WRN;
}
void i2c_set_10bit_address(uint32_t i2c, uint16_t addr)
{
I2C_CR2(i2c) = (I2C_CR2(i2c) & ~I2C_CR2_SADD_10BIT_MASK) |
((addr & 0x3FF) << I2C_CR2_SADD_10BIT_SHIFT);
}
void i2c_set_write_transfer_dir(uint32_t i2c)
{
I2C_CR2(i2c) &= ~I2C_CR2_RD_WRN;
}
/** @brief I2C Enable Interrupt
@param[in] i2c Unsigned int32. I2C register base address @ref i2c_reg_base.
@param[in] interrupt Unsigned int32. Interrupt to enable.
*/
void i2c_enable_interrupt(uint32_t i2c, uint32_t interrupt)
{
I2C_CR2(i2c) |= interrupt;
}
void i2c_set_bytes_to_transfer(uint32_t i2c, uint32_t n_bytes)
{
I2C_CR2(i2c) = (I2C_CR2(i2c) & ~I2C_CR2_NBYTES_MASK) |
(n_bytes << I2C_CR2_NBYTES_SHIFT);
}
/** @brief I2C Disable Interrupt
@param[in] i2c Unsigned int32. I2C register base address @ref i2c_reg_base.
@param[in] interrupt Unsigned int32. Interrupt to disable.
*/
void i2c_disable_interrupt(uint32_t i2c, uint32_t interrupt)
{
I2C_CR2(i2c) &= ~interrupt;
}
void i2c_enable_autoend(uint32_t i2c)
{
I2C_CR2(i2c) |= I2C_CR2_AUTOEND;
}
/** @brief I2C Enable DMA
@param[in] i2c Unsigned int32. I2C register base address @ref i2c_reg_base.
*/
void i2c_enable_dma(uint32_t i2c)
{
I2C_CR2(i2c) |= I2C_CR2_DMAEN;
}
void i2c_send_start(uint32_t i2c)
{
I2C_CR2(i2c) |= I2C_CR2_START;
}
/** @brief I2C Disable DMA
@param[in] i2c Unsigned int32. I2C register base address @ref i2c_reg_base.
*/
void i2c_disable_dma(uint32_t i2c)
{
I2C_CR2(i2c) &= ~I2C_CR2_DMAEN;
}
