/**
* @brief Read data from I2C slave.
* @param[in] fd is interface number.
* @param[in] buf is receive buffer pointer.
* @param[in] len is receive buffer length.
* @return read status.
* @retval >0 length when success.
* @retval I2C_ERR_BUSY Interface busy.
* @retval I2C_ERR_IO Interface not opened.
* @retval I2C_ERR_NODEV No such device.
* @retval I2C_ERR_NACK Slave returns an erroneous ACK.
* @retval I2C_ERR_LOSTARBITRATION arbitration lost happen.
*/
int32_t i2cRead(int32_t fd, uint8_t* buf, uint32_t len)
{
i2c_dev *dev;
if(fd != 1 && fd != 0)
return(I2C_ERR_NODEV);
dev = (i2c_dev *)( (uint32_t)&i2c_device[fd] );
if(dev->openflag == 0)
return(I2C_ERR_IO);
if(len == 0)
return 0;
if(!i2cIsBusFree(dev))
return(I2C_ERR_BUSY);
if(len > I2C_MAX_BUF_LEN - 10)
len = I2C_MAX_BUF_LEN - 10;
dev->state = I2C_STATE_READ;
dev->pos = 1;
/* Current ISR design will get one garbage byte */
dev->len = dev->subaddr_len + 1 + len + 2; /* plus 1 unused char */
dev->last_error = 0;
_i2cCalcAddr(dev, I2C_STATE_READ);
i2cEnable(dev);
i2c_out(dev, dev->buffer[0] & 0xff, I2C_TxR);
if(!i2cIsBusFree(dev))
return(I2C_ERR_BUSY);
_i2cCommand(dev, I2C_CMD_START | I2C_CMD_WRITE);
while(dev->state != I2C_STATE_NOP);
i2cDisable(dev);
if(dev->last_error)
return(dev->last_error);
memcpy(buf, dev->buffer + dev->subaddr_len + 3, len);
dev->subaddr += len;
return len;
}
/**
* @brief Write data from I2C slave.
* @param[in] fd is interface number.
* @param[in] buf is transmit buffer pointer.
* @param[in] len is transmit buffer length.
* @return write status.
* @retval >0 length when success.
* @retval I2C_ERR_BUSY Interface busy.
* @retval I2C_ERR_IO Interface not opened.
* @retval I2C_ERR_NODEV No such device.
* @retval I2C_ERR_NACK Slave returns an erroneous ACK.
* @retval I2C_ERR_LOSTARBITRATION arbitration lost happen.
*/
int32_t i2cWrite(int32_t fd, uint8_t* buf, uint32_t len)
{
i2c_dev *dev;
if(fd != 1 && fd != 0)
return(I2C_ERR_NODEV);
dev = (i2c_dev *)( (uint32_t)&i2c_device[fd] );
if(dev->openflag == 0)
return(I2C_ERR_IO);
if(len == 0)
return 0;
if(!i2cIsBusFree(dev))
return(I2C_ERR_BUSY);
if(len > I2C_MAX_BUF_LEN - 10)
len = I2C_MAX_BUF_LEN - 10;
memcpy(dev->buffer + dev->subaddr_len + 1 , buf, len);
dev->state = I2C_STATE_WRITE;
dev->pos = 1;
dev->len = dev->subaddr_len + 1 + len;
dev->last_error = 0;
_i2cCalcAddr(dev, I2C_STATE_WRITE);
i2cEnable(dev);
i2c_out(dev, dev->buffer[0] & 0xff, I2C_TxR);
if(!i2cIsBusFree(dev))
return(I2C_ERR_BUSY);
_i2cCommand(dev, I2C_CMD_START | I2C_CMD_WRITE);
while(dev->state != I2C_STATE_NOP);
i2cDisable(dev);
if(dev->last_error)
return(dev->last_error);
dev->subaddr += len;
return len;
}
static BT_HANDLE i2c_probe(const BT_INTEGRATED_DEVICE *pDevice, BT_ERROR *pError) {
BT_ERROR Error = BT_ERR_NONE;
BT_HANDLE hI2C = NULL;
const BT_RESOURCE *pResource = BT_GetIntegratedResource(pDevice, BT_RESOURCE_MEM, 0);
if(!pResource) {
Error = BT_ERR_NO_MEMORY;
goto err_free_out;
}
hI2C = BT_CreateHandle(&oHandleInterface, sizeof(struct _BT_OPAQUE_HANDLE), pError);
if(!hI2C) {
goto err_out;
}
hI2C->pRegs = (LPC11xx_I2C_REGS *) pResource->ulStart;
pResource = BT_GetIntegratedResource(pDevice, BT_RESOURCE_ENUM, 0);
if(!pResource) {
Error = BT_ERR_NO_MEMORY;
goto err_free_out;
}
hI2C->i2c_master.pDevice = pDevice;
pResource = BT_GetIntegratedResource(pDevice, BT_RESOURCE_INTEGER, 0);
if(!pResource) {
Error = BT_ERR_GENERIC;
goto err_free_out;
}
i2cSetPowerState(hI2C, BT_POWER_STATE_AWAKE);
// Reset all registers to their defaults!
ResetI2C(hI2C);
i2cEnable(hI2C);
i2c_set_clock_rate(hI2C, pResource->ulStart);
pResource = BT_GetIntegratedResource(pDevice, BT_RESOURCE_IRQ, 0);
if(!pResource) {
Error = BT_ERR_GENERIC;
goto err_free_out;
}
/* On NVIC we don't need to register interrupts, LINKER has patched vector for us
* Error = BT_RegisterInterrupt(pResource->ulStart, I2C_irq_handler, hI2C);
if(Error) {
goto err_free_out;
}*/
//@@Error = BT_EnableInterrupt(pResource->ulStart);
pResource = BT_GetIntegratedResource(pDevice, BT_RESOURCE_BUSID, 0);
if(!pResource) {
goto err_free_out;
}
BT_u32 ulBusID = pResource->ulStart;
hI2C->i2c_master.ulBusID = ulBusID;
hI2C->i2c_master.hBus = hI2C; // Save pointer to bus's private data.
hI2C->i2c_master.pDevice = pDevice;
BT_I2C_RegisterBus(&hI2C->i2c_master);
if(pError) {
*pError = Error;
}
return hI2C;
err_free_out:
BT_DestroyHandle(hI2C);
err_out:
if(pError) {
*pError = Error;
}
return NULL;
}
