/** * I2C wrapper for ChibiOS due to a bug: I2C blocking when I2C transfer suffered timeout * @see https://github.com/psas/stm32/commit/32ec8c97a1e5bf605bd5d41a89fc60b60e136af2 */ #include "ch.h" #include "hal.h" #include "pi2c.h" #define I2C_DRIVER (&I2CD1) const I2CConfig _i2cfg = { OPMODE_I2C, 200000, FAST_DUTY_CYCLE_2, }; static bool I2C_transmit(uint8_t addr, uint8_t *txbuf, uint32_t txbytes, uint8_t *rxbuf, uint32_t rxbytes, systime_t timeout) { i2cAcquireBus(I2C_DRIVER); i2cStart(I2C_DRIVER, &_i2cfg); msg_t i2c_status = i2cMasterTransmitTimeout(I2C_DRIVER, addr, txbuf, txbytes, rxbuf, rxbytes, timeout); i2cStop(I2C_DRIVER); i2cReleaseBus(I2C_DRIVER); if(i2c_status == MSG_TIMEOUT) { // Restart I2C at timeout TRACE_ERROR("I2C > TIMEOUT (ADDR 0x%02x)", addr); } else if(i2c_status == MSG_RESET) { TRACE_ERROR("I2C > RESET (ADDR 0x%02x)", addr); } return i2c_status == MSG_OK; } void pi2cInit(void) { TRACE_INFO("I2C > Initialize I2C Pins"); palSetLineMode(LINE_I2C_SDA, PAL_MODE_ALTERNATE(4) | PAL_STM32_OSPEED_HIGHEST | PAL_STM32_OTYPE_OPENDRAIN); // SDA palSetLineMode(LINE_I2C_SCL, PAL_MODE_ALTERNATE(4) | PAL_STM32_OSPEED_HIGHEST | PAL_STM32_OTYPE_OPENDRAIN); // SCL } bool I2C_write8(uint8_t address, uint8_t reg, uint8_t value) { uint8_t txbuf[] = {reg, value}; return I2C_transmit(address, txbuf, 2, NULL, 0, MS2ST(100)); } bool I2C_writeN(uint8_t address, uint8_t *txbuf, uint32_t length) { return I2C_transmit(address, txbuf, length, NULL, 0, MS2ST(100)); } bool I2C_read8(uint8_t address, uint8_t reg, uint8_t *val) { uint8_t txbuf[] = {reg}; uint8_t rxbuf[1]; bool ret = I2C_transmit(address, txbuf, 1, rxbuf, 1, MS2ST(100)); *val = rxbuf[0]; return ret; } bool I2C_read16(uint8_t address, uint8_t reg, uint16_t *val) { uint8_t txbuf[] = {reg}; uint8_t rxbuf[2]; bool ret = I2C_transmit(address, txbuf, 1, rxbuf, 2, MS2ST(100)); *val = (rxbuf[0] << 8) | rxbuf[1]; return ret; } bool I2C_read16_LE(uint8_t address, uint8_t reg, uint16_t *val) { bool ret = I2C_read16(address, reg, val); *val = (*val >> 8) | (*val << 8); return ret; } bool I2C_read8_16bitreg(uint8_t address, uint16_t reg, uint8_t *val) // 16bit register (for OV5640) { uint8_t txbuf[] = {reg >> 8, reg & 0xFF}; uint8_t rxbuf[1]; bool ret = I2C_transmit(address, txbuf, 2, rxbuf, 1, MS2ST(100)); *val = rxbuf[0]; return ret; } bool I2C_write8_16bitreg(uint8_t address, uint16_t reg, uint8_t value) // 16bit register (for OV5640) { uint8_t txbuf[] = {reg >> 8, reg & 0xFF, value}; return I2C_transmit(address, txbuf, 3, NULL, 0, MS2ST(100)); }