/* * @brief LPC8xx SPI driver * * @note * Copyright(C) NXP Semiconductors, 2012 * All rights reserved. * * @par * Software that is described herein is for illustrative purposes only * which provides customers with programming information regarding the * LPC products. This software is supplied "AS IS" without any warranties of * any kind, and NXP Semiconductors and its licenser disclaim any and * all warranties, express or implied, including all implied warranties of * merchantability, fitness for a particular purpose and non-infringement of * intellectual property rights. NXP Semiconductors assumes no responsibility * or liability for the use of the software, conveys no license or rights under any * patent, copyright, mask work right, or any other intellectual property rights in * or to any products. NXP Semiconductors reserves the right to make changes * in the software without notification. NXP Semiconductors also makes no * representation or warranty that such application will be suitable for the * specified use without further testing or modification. * * @par * Permission to use, copy, modify, and distribute this software and its * documentation is hereby granted, under NXP Semiconductors' and its * licensor's relevant copyrights in the software, without fee, provided that it * is used in conjunction with NXP Semiconductors microcontrollers. This * copyright, permission, and disclaimer notice must appear in all copies of * this code. */ #include "chip.h" /***************************************************************************** * Private types/enumerations/variables ****************************************************************************/ static volatile bool xmitOn; static volatile bool deasserted; /***************************************************************************** * Public types/enumerations/variables ****************************************************************************/ /***************************************************************************** * Private functions ****************************************************************************/ STATIC void SPI_Send_Data_RxIgnore(LPC_SPI_T *pSPI, SPI_DATA_SETUP_T *pXfSetup) { if (pXfSetup->TxCnt == (pXfSetup->Length - 1)) { Chip_SPI_SendLastFrame_RxIgnore(pSPI, pXfSetup->pTx[pXfSetup->TxCnt], pXfSetup->DataSize); } else { Chip_SPI_SendMidFrame(pSPI, pXfSetup->pTx[pXfSetup->TxCnt]); } pXfSetup->TxCnt++; } STATIC void SPI_Send_Data(LPC_SPI_T *pSPI, SPI_DATA_SETUP_T *pXfSetup) { if (pXfSetup->TxCnt == (pXfSetup->Length - 1)) { Chip_SPI_SendLastFrame(pSPI, pXfSetup->pTx[pXfSetup->TxCnt], pXfSetup->DataSize); } else { Chip_SPI_SendMidFrame(pSPI, pXfSetup->pTx[pXfSetup->TxCnt]); } pXfSetup->TxCnt++; } STATIC void SPI_Send_Dummy(LPC_SPI_T *pSPI, SPI_DATA_SETUP_T *pXfSetup) { if (pXfSetup->RxCnt == (pXfSetup->Length - 1)) { Chip_SPI_SendLastFrame(pSPI, 0x55, pXfSetup->DataSize); } else { Chip_SPI_SendMidFrame(pSPI, 0x55); } } STATIC void SPI_Receive_Data(LPC_SPI_T *pSPI, SPI_DATA_SETUP_T *pXfSetup) { pXfSetup->pRx[pXfSetup->RxCnt] = Chip_SPI_ReceiveFrame(pSPI); pXfSetup->RxCnt++; } /* Determine SSEL associated with the current data value */ STATIC uint8_t Chip_SPIS_FindSSEL(LPC_SPI_T *pSPI, uint32_t data) { int i; uint8_t ssel = 0; for (i = 0; i <= 3; i++) { if ((data & SPI_RXDAT_RXSSELNUM_INACTIVE(i)) == 0) { /* Signal is active on low */ ssel = (uint8_t) i; } } return ssel; } /***************************************************************************** * Public functions ****************************************************************************/ /* Calculate the Clock Rate Divider for SPI Peripheral */ uint32_t Chip_SPI_CalClkRateDivider(LPC_SPI_T *pSPI, uint32_t bitRate) { uint32_t SPIClk; uint32_t DivVal = 1; /* Get SPI clock rate */ SPIClk = Chip_Clock_GetSystemClockRate(); /*The peripheral clock for both SPIs is the system clock*/ DivVal = SPIClk / bitRate; return DivVal; } /* Configure SPI Delay parameters */ void Chip_SPI_DelayConfig(LPC_SPI_T *pSPI, SPI_DELAY_CONFIG_T *pConfig) { uint32_t delayValue = SPI_DLY_PRE_DELAY(pConfig->PreDelay) | SPI_DLY_POST_DELAY(pConfig->PostDelay) | SPI_DLY_FRAME_DELAY(pConfig->FrameDelay); if (pConfig->TransferDelay) { delayValue |= SPI_DLY_TRANSFER_DELAY(pConfig->TransferDelay - 1); } pSPI->DLY = delayValue; } /* Disable/Enable Interrupt */ void Chip_SPI_Int_Cmd(LPC_SPI_T *pSPI, uint32_t IntMask, FunctionalState NewState) { if (NewState == ENABLE) { pSPI->INTENSET = IntMask; } else { pSPI->INTENCLR = IntMask; } } /*Send and Receive SPI Data */ uint32_t Chip_SPI_RWFrames_Blocking(LPC_SPI_T *pSPI, SPI_DATA_SETUP_T *pXfSetup) { uint32_t Status; /* Clear status */ Chip_SPI_ClearStatus(pSPI, SPI_STAT_CLR_RXOV | SPI_STAT_CLR_TXUR | SPI_STAT_CLR_SSA | SPI_STAT_CLR_SSD); Chip_SPI_SetControlInfo(pSPI, pXfSetup->DataSize, SPI_TXCTL_ASSERT_SSEL | SPI_TXCTL_EOF); pXfSetup->TxCnt = pXfSetup->RxCnt = 0; while ((pXfSetup->TxCnt < pXfSetup->Length) || (pXfSetup->RxCnt < pXfSetup->Length)) { Status = Chip_SPI_GetStatus(pSPI); /* In case of TxReady */ if ((Status & SPI_STAT_TXRDY) && (pXfSetup->TxCnt < pXfSetup->Length)) { SPI_Send_Data(pSPI, pXfSetup); } /*In case of Rx ready */ if ((Status & SPI_STAT_RXRDY) && (pXfSetup->RxCnt < pXfSetup->Length)) { SPI_Receive_Data(pSPI, pXfSetup); } } /* Check error */ if (Chip_SPI_GetStatus(pSPI) & (SPI_STAT_CLR_RXOV | SPI_STAT_CLR_TXUR)) { return 0; } return pXfSetup->TxCnt; } uint32_t Chip_SPI_WriteFrames_Blocking(LPC_SPI_T *pSPI, SPI_DATA_SETUP_T *pXfSetup) { /* Clear status */ Chip_SPI_ClearStatus(pSPI, SPI_STAT_CLR_RXOV | SPI_STAT_CLR_TXUR | SPI_STAT_CLR_SSA | SPI_STAT_CLR_SSD); Chip_SPI_SetControlInfo(pSPI, pXfSetup->DataSize, SPI_TXCTL_ASSERT_SSEL | SPI_TXCTL_EOF | SPI_TXCTL_RXIGNORE); pXfSetup->TxCnt = pXfSetup->RxCnt = 0; while (pXfSetup->TxCnt < pXfSetup->Length) { /* Wait for TxReady */ while (!(Chip_SPI_GetStatus(pSPI) & SPI_STAT_TXRDY)) {} SPI_Send_Data_RxIgnore(pSPI, pXfSetup); } /* Make sure the last frame sent completely*/ while (!(Chip_SPI_GetStatus(pSPI) & SPI_STAT_SSD)) {} Chip_SPI_ClearStatus(pSPI, SPI_STAT_CLR_SSD); /* Check overrun error */ if (Chip_SPI_GetStatus(pSPI) & SPI_STAT_CLR_TXUR) { return 0; } return pXfSetup->TxCnt; } uint32_t Chip_SPI_ReadFrames_Blocking(LPC_SPI_T *pSPI, SPI_DATA_SETUP_T *pXfSetup) { /* Clear status */ Chip_SPI_ClearStatus(pSPI, SPI_STAT_CLR_RXOV | SPI_STAT_CLR_TXUR | SPI_STAT_CLR_SSA | SPI_STAT_CLR_SSD); Chip_SPI_SetControlInfo(pSPI, pXfSetup->DataSize, SPI_TXCTL_ASSERT_SSEL | SPI_TXCTL_EOF); pXfSetup->TxCnt = pXfSetup->RxCnt = 0; while (pXfSetup->RxCnt < pXfSetup->Length) { /* Wait for TxReady */ while (!(Chip_SPI_GetStatus(pSPI) & SPI_STAT_TXRDY)) {} SPI_Send_Dummy(pSPI, pXfSetup); /* Wait for receive data */ while (!(Chip_SPI_GetStatus(pSPI) & SPI_STAT_RXRDY)) {} SPI_Receive_Data(pSPI, pXfSetup); } /* Check overrun error */ if (Chip_SPI_GetStatus(pSPI) & (SPI_STAT_CLR_RXOV | SPI_STAT_CLR_TXUR)) { return 0; } return pXfSetup->RxCnt; } /* SPI Interrupt Read/Write with 8-bit frame width */ Status Chip_SPI_Int_RWFrames(LPC_SPI_T *pSPI, SPI_DATA_SETUP_T *pXfSetup) { uint32_t Status; Status = Chip_SPI_GetStatus(pSPI); /* Check error in INTSTAT register */ if (Status & (SPI_STAT_RXOV | SPI_STAT_TXUR)) { return ERROR; } if (pXfSetup->TxCnt == 0) { Chip_SPI_SetControlInfo(pSPI, pXfSetup->DataSize, SPI_TXCTL_ASSERT_SSEL | SPI_TXCTL_EOF); } if (pXfSetup->pRx == NULL) { if ((Status & SPI_STAT_TXRDY) && (pXfSetup->TxCnt < pXfSetup->Length)) { SPI_Send_Data_RxIgnore(pSPI, pXfSetup); } } else { /* check if Tx ready */ if ((Status & SPI_STAT_TXRDY) && (pXfSetup->TxCnt < pXfSetup->Length)) { SPI_Send_Data(pSPI, pXfSetup); } /* check if RX FIFO contains data */ if ((Status & SPI_STAT_RXRDY) && (pXfSetup->RxCnt < pXfSetup->Length)) { SPI_Receive_Data(pSPI, pXfSetup); } } return SUCCESS; } /* Get SPI master bit rate */ uint32_t Chip_SPIM_GetClockRate(LPC_SPI_T *pSPI) { return Chip_Clock_GetSystemClockRate() / ((pSPI->DIV & ~SPI_DIV_RESERVED) + 1); } /* Set SPI master bit rate */ uint32_t Chip_SPIM_SetClockRate(LPC_SPI_T *pSPI, uint32_t rate) { uint32_t baseClock, div; /* Get peripheral base clock rate */ baseClock = Chip_Clock_GetSystemClockRate(); /* Compute divider */ div = baseClock / rate; /* Limit values */ if (div == 0) { div = 1; } else if (div > 0x10000) { div = 0x10000; } pSPI->DIV = div - 1; return Chip_SPIM_GetClockRate(pSPI); } /* Configure SPI Delay parameters */ void Chip_SPIM_DelayConfig(LPC_SPI_T *pSPI, SPIM_DELAY_CONFIG_T *pConfig) { pSPI->DLY = (SPI_DLY_PRE_DELAY(pConfig->PreDelay) | SPI_DLY_POST_DELAY(pConfig->PostDelay) | SPI_DLY_FRAME_DELAY(pConfig->FrameDelay) | SPI_DLY_TRANSFER_DELAY(pConfig->TransferDelay - 1)); } /* Assert a SPI select */ void Chip_SPIM_AssertSSEL(LPC_SPI_T *pSPI, uint8_t sselNum) { uint32_t reg; reg = pSPI->TXCTRL & SPI_TXDATCTL_CTRLMASK; /* Assert a SSEL line by driving it low */ reg &= ~SPI_TXDATCTL_DEASSERTNUM_SSEL(sselNum); pSPI->TXCTRL = reg; } /* Deassert a SPI select */ void Chip_SPIM_DeAssertSSEL(LPC_SPI_T *pSPI, uint8_t sselNum) { uint32_t reg; reg = pSPI->TXCTRL & SPI_TXDATCTL_CTRLMASK; pSPI->TXCTRL = reg | SPI_TXDATCTL_DEASSERTNUM_SSEL(sselNum); } /* SPI master transfer state change handler */ void Chip_SPIM_XferHandler(LPC_SPI_T *pSPI, SPIM_XFER_T *xfer) { uint32_t data; uint8_t flen; /* Get length of a receive value */ flen = ((pSPI->TXCTRL & ~SPI_TXCTRL_RESERVED) >> 24) & 0xF; /* Master asserts slave */ if ((Chip_SPI_GetStatus(pSPI) & SPI_STAT_SSA) != 0) { Chip_SPI_ClearStatus(pSPI, SPI_STAT_SSA); /* SSEL assertion callback */ xfer->pCB->masterXferCSAssert(xfer); } /* Slave de-assertion */ if ((Chip_SPI_GetStatus(pSPI) & SPI_STAT_SSD) != 0) { Chip_SPI_ClearStatus(pSPI, SPI_STAT_SSD); /* If transmitter disabled and deassert happens, the transfer is done */ if (xmitOn == false) { xfer->pCB->mMasterXferDone(xfer); } } /* Transmit data? */ while (((Chip_SPI_GetStatus(pSPI) & SPI_STAT_TXRDY) != 0) && (xmitOn == true)) { if ((xfer->txCount == 1) && (xfer->terminate)) { /* Transfer is done, this will be last data */ Chip_SPIM_ForceEndOfTransfer(pSPI); xmitOn = false; } else if (xfer->txCount == 0) { /* Request a new buffer first */ xfer->pCB->masterXferSend(xfer); } if (xfer->txCount > 0) { /* Send 0 if ignoring transmit */ if (xfer->pTXData8 == NULL) { data = 0; } else { /* Copy buffer to data */ if (flen > 8) { data = (uint32_t) *xfer->pTXData16; xfer->pTXData16++; } else { data = (uint32_t) *xfer->pTXData8; xfer->pTXData8++; } xfer->dataTXferred++; } Chip_SPI_WriteTXData(pSPI, data); xfer->txCount--; } } /* Data received? */ while ((Chip_SPI_GetStatus(pSPI) & SPI_STAT_RXRDY) != 0) { /* Get raw data and status */ data = Chip_SPI_ReadRawRXFifo(pSPI); /* Only copy data when not ignoring receive */ if (xfer->pRXData8 != NULL) { /* Enough size in current buffers? */ if (xfer->rxCount == 0) { /* Request a new buffer first */ xfer->pCB->masterXferRecv(xfer); } /* Copy data to buffer */ if (xfer->rxCount > 0) { if (flen > 8) { *xfer->pRXData16 = (uint16_t) (data & 0xFFFF); xfer->pRXData16++; } else { *xfer->pRXData8 = (uint8_t) (data & 0xFF); xfer->pRXData8++; } xfer->dataRXferred++; xfer->rxCount--; } } } } /* Start non-blocking SPI master transfer */ void Chip_SPIM_Xfer(LPC_SPI_T *pSPI, SPIM_XFER_T *xfer) { /* Setup SPI master select, data length, EOT/EOF timing, and RX data ignore */ pSPI->TXCTRL = xfer->options | SPI_TXDATCTL_DEASSERT_ALL; Chip_SPIM_AssertSSEL(pSPI, xfer->sselNum); /* Clear initial transfer states */ xfer->dataRXferred = xfer->dataTXferred = 0; /* Call main handler to start transfer */ xmitOn = true; Chip_SPIM_XferHandler(pSPI, xfer); } /* Perform blocking SPI master transfer */ void Chip_SPIM_XferBlocking(LPC_SPI_T *pSPI, SPIM_XFER_T *xfer) { /* Start trasnfer */ Chip_SPIM_Xfer(pSPI, xfer); /* Wait for termination */ while (xmitOn == true) { Chip_SPIM_XferHandler(pSPI, xfer); } } /* SPI slave transfer state change handler */ uint32_t Chip_SPIS_XferHandler(LPC_SPI_T *pSPI, SPIS_XFER_T *xfer) { uint32_t staterr, data; uint8_t flen; /* Get length of a receive value */ flen = ((pSPI->TXCTRL & ~SPI_TXCTRL_RESERVED) >> 24) & 0xF; /* Get errors for later, we'll continue even if errors occur, but we notify caller on return */ staterr = Chip_SPI_GetStatus(pSPI) & (SPI_STAT_RXOV | SPI_STAT_TXUR); if (staterr != 0) { Chip_SPI_ClearStatus(pSPI, staterr); } /* Slave assertion */ if ((Chip_SPI_GetStatus(pSPI) & SPI_STAT_SSA) != 0) { Chip_SPI_ClearStatus(pSPI, SPI_STAT_SSA); /* Determine SPI select. Read the data FIFO to get the slave number. Data should not be in the receive FIFO yet, only the statuses */ xfer->sselNum = Chip_SPIS_FindSSEL(pSPI, Chip_SPI_ReadRawRXFifo(pSPI)); /* SSEL assertion callback */ xfer->pCB->slaveXferCSAssert(xfer); } /* Slave de-assertion */ if ((Chip_SPI_GetStatus(pSPI) & SPI_STAT_SSD) != 0) { Chip_SPI_ClearStatus(pSPI, SPI_STAT_SSD); deasserted = true; xfer->pCB->slaveXferCSDeAssert(xfer); } /* Transmit data? */ while ((Chip_SPI_GetStatus(pSPI) & SPI_STAT_TXRDY) != 0) { if (xfer->txCount == 0) { /* Request a new buffer first */ xfer->pCB->slaveXferSend(xfer); } /* Send 0 on empty buffer or count */ if ((xfer->txCount == 0) || (xfer->pTXData8 == NULL)) { data = 0; } else { /* Copy buffer to data */ if (flen > 8) { data = (uint32_t) *xfer->pTXData16; xfer->pTXData16++; } else { data = (uint32_t) *xfer->pTXData8; xfer->pTXData8++; } xfer->dataTXferred++; xfer->txCount--; } Chip_SPI_WriteTXData(pSPI, data); } /* Data received? */ while ((Chip_SPI_GetStatus(pSPI) & SPI_STAT_RXRDY) != 0) { /* Get raw data and status */ data = Chip_SPI_ReadRawRXFifo(pSPI); /* Only copy data when not ignoring receive */ if (xfer->pRXData8 != NULL) { /* Enough size in current buffers? */ if (xfer->rxCount == 0) { /* Request a new buffer first */ xfer->pCB->slaveXferRecv(xfer); } /* Copy data to buffer */ if (flen > 8) { *xfer->pRXData16 = (uint16_t) (data & 0xFFFF); xfer->pRXData16++; } else { *xfer->pRXData8 = (uint8_t) (data & 0xFF); xfer->pRXData8++; } xfer->dataRXferred++; xfer->rxCount--; } } return staterr; } /* SPI slave transfer blocking function */ uint32_t Chip_SPIS_XferBlocking(LPC_SPI_T *pSPI, SPIS_XFER_T *xfer) { uint32_t status = 0; /* Wait forever until deassertion event */ deasserted = false; while ((!deasserted) && (status == 0)) { status = Chip_SPIS_XferHandler(pSPI, xfer); } return status; }