From 7f4da522479c0f00126219f0c23b804c3a93d7a6 Mon Sep 17 00:00:00 2001 From: Yuval Adam Date: Sun, 16 Mar 2014 14:40:16 +0200 Subject: Add driver lib for projects which require it --- driverlib/ssi.c | 1150 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 1150 insertions(+) create mode 100644 driverlib/ssi.c (limited to 'driverlib/ssi.c') diff --git a/driverlib/ssi.c b/driverlib/ssi.c new file mode 100644 index 0000000..ebe875b --- /dev/null +++ b/driverlib/ssi.c @@ -0,0 +1,1150 @@ +//***************************************************************************** +// +// ssi.c - Driver for Synchronous Serial Interface. +// +// Copyright (c) 2005-2014 Texas Instruments Incorporated. All rights reserved. +// Software License Agreement +// +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions +// are met: +// +// Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// +// Redistributions in binary form must reproduce the above copyright +// notice, this list of conditions and the following disclaimer in the +// documentation and/or other materials provided with the +// distribution. +// +// Neither the name of Texas Instruments Incorporated nor the names of +// its contributors may be used to endorse or promote products derived +// from this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +// +// This is part of revision 2.1.0.12573 of the Tiva Peripheral Driver Library. +// +//***************************************************************************** + +//***************************************************************************** +// +//! \addtogroup ssi_api +//! @{ +// +//***************************************************************************** + +#include +#include +#include "inc/hw_ints.h" +#include "inc/hw_memmap.h" +#include "inc/hw_ssi.h" +#include "inc/hw_sysctl.h" +#include "inc/hw_types.h" +#include "driverlib/debug.h" +#include "driverlib/interrupt.h" +#include "driverlib/ssi.h" + +//***************************************************************************** +// +// A mapping of timer base address to interrupt number. +// +//***************************************************************************** +static const uint32_t g_ppui32SSIIntMap[][2] = +{ + { SSI0_BASE, INT_SSI0_TM4C123 }, + { SSI1_BASE, INT_SSI1_TM4C123 }, + { SSI2_BASE, INT_SSI2_TM4C123 }, + { SSI3_BASE, INT_SSI3_TM4C123 }, +}; +static const uint_fast8_t g_ui8SSIIntMapRows = + sizeof(g_ppui32SSIIntMap) / sizeof(g_ppui32SSIIntMap[0]); + +static const uint32_t g_ppui32SSIIntMapSnowflake[][2] = +{ + { SSI0_BASE, INT_SSI0_TM4C129 }, + { SSI1_BASE, INT_SSI1_TM4C129 }, + { SSI2_BASE, INT_SSI2_TM4C129 }, + { SSI3_BASE, INT_SSI3_TM4C129 }, +}; +static const uint_fast8_t g_ui8SSIIntMapSnowflakeRows = + sizeof(g_ppui32SSIIntMapSnowflake) / sizeof(g_ppui32SSIIntMapSnowflake[0]); + +//***************************************************************************** +// +//! \internal +//! Checks an SSI base address. +//! +//! \param ui32Base specifies the SSI module base address. +//! +//! This function determines if a SSI module base address is valid. +//! +//! \return Returns \b true if the base address is valid and \b false +//! otherwise. +// +//***************************************************************************** +#ifdef DEBUG +static bool +_SSIBaseValid(uint32_t ui32Base) +{ + return((ui32Base == SSI0_BASE) || (ui32Base == SSI1_BASE) || + (ui32Base == SSI2_BASE) || (ui32Base == SSI3_BASE)); +} +#endif + +//***************************************************************************** +// +//! Returns the interrupt number of SSI module . +//! +//! \param ui32Base is the base address of the SSI module. +//! +//! This function returns the interrupt number for the SSI module with the base +//! address passed in the \e ui32Base parameter. +//! +//! \return Returns an SSI interrupt number, or 0 if the interrupt does not +//! exist. +// +//***************************************************************************** +static uint32_t +_SSIIntNumberGet(uint32_t ui32Base) +{ + uint_fast8_t ui8Idx, ui8Rows; + const uint32_t (*ppui32SSIIntMap)[2]; + + // + // Check the arguments. + // + ASSERT(_SSIBaseValid(ui32Base)); + + ppui32SSIIntMap = g_ppui32SSIIntMap; + ui8Rows = g_ui8SSIIntMapRows; + + if(CLASS_IS_TM4C129) + { + ppui32SSIIntMap = g_ppui32SSIIntMapSnowflake; + ui8Rows = g_ui8SSIIntMapSnowflakeRows; + } + + // + // Loop through the table that maps SSI base addresses to interrupt + // numbers. + // + for(ui8Idx = 0; ui8Idx < ui8Rows; ui8Idx++) + { + // + // See if this base address matches. + // + if(ppui32SSIIntMap[ui8Idx][0] == ui32Base) + { + // + // Return the corresponding interrupt number. + // + return(ppui32SSIIntMap[ui8Idx][1]); + } + } + + // + // The base address could not be found, so return an error. + // + return(0); +} + +//***************************************************************************** +// +//! Configures the synchronous serial interface. +//! +//! \param ui32Base specifies the SSI module base address. +//! \param ui32SSIClk is the rate of the clock supplied to the SSI module. +//! \param ui32Protocol specifies the data transfer protocol. +//! \param ui32Mode specifies the mode of operation. +//! \param ui32BitRate specifies the clock rate. +//! \param ui32DataWidth specifies number of bits transferred per frame. +//! +//! This function configures the synchronous serial interface. It sets +//! the SSI protocol, mode of operation, bit rate, and data width. +//! +//! The \e ui32Protocol parameter defines the data frame format. The +//! \e ui32Protocol parameter can be one of the following values: +//! \b SSI_FRF_MOTO_MODE_0, \b SSI_FRF_MOTO_MODE_1, \b SSI_FRF_MOTO_MODE_2, +//! \b SSI_FRF_MOTO_MODE_3, \b SSI_FRF_TI, or \b SSI_FRF_NMW. Note that +//! the \b SSI_FRF_NMW option is only available on some devices. Refer to the +//! device data sheet to determine if the Microwire format is supported on +//! a particular device. The Motorola frame formats encode the following +//! polarity and phase configurations: +//! +//! 
+//! Polarity Phase       Mode
+//!   0       0   SSI_FRF_MOTO_MODE_0
+//!   0       1   SSI_FRF_MOTO_MODE_1
+//!   1       0   SSI_FRF_MOTO_MODE_2
+//!   1       1   SSI_FRF_MOTO_MODE_3
+//!
+//! +//! The \e ui32Mode parameter defines the operating mode of the SSI module. +//! The SSI module can operate as a master or slave; if it is a slave, the SSI +//! can be configured to disable output on its serial output line. The +//! \e ui32Mode parameter can be one of the following values: +//! \b SSI_MODE_MASTER, \b SSI_MODE_SLAVE, or \b SSI_MODE_SLAVE_OD. +//! +//! The \e ui32BitRate parameter defines the bit rate for the SSI. This bit +//! rate must satisfy the following clock ratio criteria: +//! +//! - FSSI >= 2 * bit rate (master mode) +//! - FSSI >= 12 * bit rate (slave modes) +//! +//! where FSSI is the frequency of the clock supplied to the SSI module. Note +//! that there are frequency limits for FSSI that are described in the Bit Rate +//! Generation section of the SSI chapter in the data sheet. +//! +//! The \e ui32DataWidth parameter defines the width of the data transfers and +//! can be a value between 4 and 16, inclusive. +//! +//! The peripheral clock is the same as the processor clock. This value is +//! returned by SysCtlClockGet(), or it can be explicitly hard coded if it is +//! constant and known (to save the code/execution overhead of a call to +//! SysCtlClockGet()). +//! +//! \return None. +// +//***************************************************************************** +void +SSIConfigSetExpClk(uint32_t ui32Base, uint32_t ui32SSIClk, + uint32_t ui32Protocol, uint32_t ui32Mode, + uint32_t ui32BitRate, uint32_t ui32DataWidth) +{ + uint32_t ui32MaxBitRate; + uint32_t ui32RegVal; + uint32_t ui32PreDiv; + uint32_t ui32SCR; + uint32_t ui32SPH_SPO; + + // + // Check the arguments. + // + ASSERT(_SSIBaseValid(ui32Base)); + ASSERT((ui32Protocol == SSI_FRF_MOTO_MODE_0) || + (ui32Protocol == SSI_FRF_MOTO_MODE_1) || + (ui32Protocol == SSI_FRF_MOTO_MODE_2) || + (ui32Protocol == SSI_FRF_MOTO_MODE_3) || + (ui32Protocol == SSI_FRF_TI) || + (ui32Protocol == SSI_FRF_NMW)); + ASSERT((ui32Mode == SSI_MODE_MASTER) || + (ui32Mode == SSI_MODE_SLAVE) || + (ui32Mode == SSI_MODE_SLAVE_OD)); + ASSERT(((ui32Mode == SSI_MODE_MASTER) && + (ui32BitRate <= (ui32SSIClk / 2))) || + ((ui32Mode != SSI_MODE_MASTER) && + (ui32BitRate <= (ui32SSIClk / 12)))); + ASSERT((ui32SSIClk / ui32BitRate) <= (254 * 256)); + ASSERT((ui32DataWidth >= 4) && (ui32DataWidth <= 16)); + + // + // Set the mode. + // + ui32RegVal = (ui32Mode == SSI_MODE_SLAVE_OD) ? SSI_CR1_SOD : 0; + ui32RegVal |= (ui32Mode == SSI_MODE_MASTER) ? 0 : SSI_CR1_MS; + HWREG(ui32Base + SSI_O_CR1) = ui32RegVal; + + // + // Set the clock predivider. + // + ui32MaxBitRate = ui32SSIClk / ui32BitRate; + ui32PreDiv = 0; + do + { + ui32PreDiv += 2; + ui32SCR = (ui32MaxBitRate / ui32PreDiv) - 1; + } + while(ui32SCR > 255); + HWREG(ui32Base + SSI_O_CPSR) = ui32PreDiv; + + // + // Set protocol and clock rate. + // + ui32SPH_SPO = (ui32Protocol & 3) << 6; + ui32Protocol &= SSI_CR0_FRF_M; + ui32RegVal = (ui32SCR << 8) | ui32SPH_SPO | ui32Protocol | + (ui32DataWidth - 1); + HWREG(ui32Base + SSI_O_CR0) = ui32RegVal; +} + +//***************************************************************************** +// +//! Enables the synchronous serial interface. +//! +//! \param ui32Base specifies the SSI module base address. +//! +//! This function enables operation of the synchronous serial interface. The +//! synchronous serial interface must be configured before it is enabled. +//! +//! \return None. +// +//***************************************************************************** +void +SSIEnable(uint32_t ui32Base) +{ + // + // Check the arguments. + // + ASSERT(_SSIBaseValid(ui32Base)); + + // + // Read-modify-write the enable bit. + // + HWREG(ui32Base + SSI_O_CR1) |= SSI_CR1_SSE; +} + +//***************************************************************************** +// +//! Disables the synchronous serial interface. +//! +//! \param ui32Base specifies the SSI module base address. +//! +//! This function disables operation of the synchronous serial interface. +//! +//! \return None. +// +//***************************************************************************** +void +SSIDisable(uint32_t ui32Base) +{ + // + // Check the arguments. + // + ASSERT(_SSIBaseValid(ui32Base)); + + // + // Read-modify-write the enable bit. + // + HWREG(ui32Base + SSI_O_CR1) &= ~(SSI_CR1_SSE); +} + +//***************************************************************************** +// +//! Registers an interrupt handler for the synchronous serial interface. +//! +//! \param ui32Base specifies the SSI module base address. +//! \param pfnHandler is a pointer to the function to be called when the +//! synchronous serial interface interrupt occurs. +//! +//! This function registers the handler to be called when an SSI interrupt +//! occurs. This function enables the global interrupt in the interrupt +//! controller; specific SSI interrupts must be enabled via SSIIntEnable(). If +//! necessary, it is the interrupt handler's responsibility to clear the +//! interrupt source via SSIIntClear(). +//! +//! \sa IntRegister() for important information about registering interrupt +//! handlers. +//! +//! \return None. +// +//***************************************************************************** +void +SSIIntRegister(uint32_t ui32Base, void (*pfnHandler)(void)) +{ + uint32_t ui32Int; + + // + // Check the arguments. + // + ASSERT(_SSIBaseValid(ui32Base)); + + // + // Determine the interrupt number based on the SSI module. + // + ui32Int = _SSIIntNumberGet(ui32Base); + + ASSERT(ui32Int != 0); + + // + // Register the interrupt handler, returning an error if an error occurs. + // + IntRegister(ui32Int, pfnHandler); + + // + // Enable the synchronous serial interface interrupt. + // + IntEnable(ui32Int); +} + +//***************************************************************************** +// +//! Unregisters an interrupt handler for the synchronous serial interface. +//! +//! \param ui32Base specifies the SSI module base address. +//! +//! This function clears the handler to be called when an SSI interrupt +//! occurs. This function also masks off the interrupt in the interrupt +//! controller so that the interrupt handler no longer is called. +//! +//! \sa IntRegister() for important information about registering interrupt +//! handlers. +//! +//! \return None. +// +//***************************************************************************** +void +SSIIntUnregister(uint32_t ui32Base) +{ + uint32_t ui32Int; + + // + // Check the arguments. + // + ASSERT(_SSIBaseValid(ui32Base)); + + // + // Determine the interrupt number based on the SSI module. + // + ui32Int = _SSIIntNumberGet(ui32Base); + + ASSERT(ui32Int != 0); + + // + // Disable the interrupt. + // + IntDisable(ui32Int); + + // + // Unregister the interrupt handler. + // + IntUnregister(ui32Int); +} + +//***************************************************************************** +// +//! Enables individual SSI interrupt sources. +//! +//! \param ui32Base specifies the SSI module base address. +//! \param ui32IntFlags is a bit mask of the interrupt sources to be enabled. +//! +//! This function enables the indicated SSI interrupt sources. Only the +//! sources that are enabled can be reflected to the processor interrupt; +//! disabled sources have no effect on the processor. The \e ui32IntFlags +//! parameter can be any of the \b SSI_TXFF, \b SSI_RXFF, \b SSI_RXTO, or +//! \b SSI_RXOR values. +//! +//! \return None. +// +//***************************************************************************** +void +SSIIntEnable(uint32_t ui32Base, uint32_t ui32IntFlags) +{ + // + // Check the arguments. + // + ASSERT(_SSIBaseValid(ui32Base)); + + // + // Enable the specified interrupts. + // + HWREG(ui32Base + SSI_O_IM) |= ui32IntFlags; +} + +//***************************************************************************** +// +//! Disables individual SSI interrupt sources. +//! +//! \param ui32Base specifies the SSI module base address. +//! \param ui32IntFlags is a bit mask of the interrupt sources to be disabled. +//! +//! This function disables the indicated SSI interrupt sources. The +//! \e ui32IntFlags parameter can be any of the \b SSI_TXFF, \b SSI_RXFF, +//! \b SSI_RXTO, or \b SSI_RXOR values. +//! +//! \return None. +// +//***************************************************************************** +void +SSIIntDisable(uint32_t ui32Base, uint32_t ui32IntFlags) +{ + // + // Check the arguments. + // + ASSERT(_SSIBaseValid(ui32Base)); + + // + // Disable the specified interrupts. + // + HWREG(ui32Base + SSI_O_IM) &= ~(ui32IntFlags); +} + +//***************************************************************************** +// +//! Gets the current interrupt status. +//! +//! \param ui32Base specifies the SSI module base address. +//! \param bMasked is \b false if the raw interrupt status is required or +//! \b true if the masked interrupt status is required. +//! +//! This function returns the interrupt status for the SSI module. Either the +//! raw interrupt status or the status of interrupts that are allowed to +//! reflect to the processor can be returned. +//! +//! \return The current interrupt status, enumerated as a bit field of +//! \b SSI_TXFF, \b SSI_RXFF, \b SSI_RXTO, and \b SSI_RXOR. +// +//***************************************************************************** +uint32_t +SSIIntStatus(uint32_t ui32Base, bool bMasked) +{ + // + // Check the arguments. + // + ASSERT(_SSIBaseValid(ui32Base)); + + // + // Return either the interrupt status or the raw interrupt status as + // requested. + // + if(bMasked) + { + return(HWREG(ui32Base + SSI_O_MIS)); + } + else + { + return(HWREG(ui32Base + SSI_O_RIS)); + } +} + +//***************************************************************************** +// +//! Clears SSI interrupt sources. +//! +//! \param ui32Base specifies the SSI module base address. +//! \param ui32IntFlags is a bit mask of the interrupt sources to be cleared. +//! +//! This function clears the specified SSI interrupt sources so that they no +//! longer assert. This function must be called in the interrupt handler to +//! keep the interrupts from being triggered again immediately upon exit. The +//! \e ui32IntFlags parameter can consist of either or both the \b SSI_RXTO and +//! \b SSI_RXOR values. +//! +//! \note Because there is a write buffer in the Cortex-M processor, it may +//! take several clock cycles before the interrupt source is actually cleared. +//! Therefore, it is recommended that the interrupt source be cleared early in +//! the interrupt handler (as opposed to the very last action) to avoid +//! returning from the interrupt handler before the interrupt source is +//! actually cleared. Failure to do so may result in the interrupt handler +//! being immediately reentered (because the interrupt controller still sees +//! the interrupt source asserted). +//! +//! \return None. +// +//***************************************************************************** +void +SSIIntClear(uint32_t ui32Base, uint32_t ui32IntFlags) +{ + // + // Check the arguments. + // + ASSERT(_SSIBaseValid(ui32Base)); + + // + // Clear the requested interrupt sources. + // + HWREG(ui32Base + SSI_O_ICR) = ui32IntFlags; +} + +//***************************************************************************** +// +//! Puts a data element into the SSI transmit FIFO. +//! +//! \param ui32Base specifies the SSI module base address. +//! \param ui32Data is the data to be transmitted over the SSI interface. +//! +//! This function places the supplied data into the transmit FIFO of the +//! specified SSI module. If there is no space available in the transmit FIFO, +//! this function waits until there is space available before returning. +//! +//! \note The upper 32 - N bits of \e ui32Data are discarded by the hardware, +//! where N is the data width as configured by SSIConfigSetExpClk(). For +//! example, if the interface is configured for 8-bit data width, the upper 24 +//! bits of \e ui32Data are discarded. +//! +//! \return None. +// +//***************************************************************************** +void +SSIDataPut(uint32_t ui32Base, uint32_t ui32Data) +{ + // + // Check the arguments. + // + ASSERT(_SSIBaseValid(ui32Base)); + ASSERT((ui32Data & (0xfffffffe << (HWREG(ui32Base + SSI_O_CR0) & + SSI_CR0_DSS_M))) == 0); + + // + // Wait until there is space. + // + while(!(HWREG(ui32Base + SSI_O_SR) & SSI_SR_TNF)) + { + } + + // + // Write the data to the SSI. + // + HWREG(ui32Base + SSI_O_DR) = ui32Data; +} + +//***************************************************************************** +// +//! Puts a data element into the SSI transmit FIFO. +//! +//! \param ui32Base specifies the SSI module base address. +//! \param ui32Data is the data to be transmitted over the SSI interface. +//! +//! This function places the supplied data into the transmit FIFO of the +//! specified SSI module. If there is no space in the FIFO, then this function +//! returns a zero. +//! +//! \note The upper 32 - N bits of \e ui32Data are discarded by the hardware, +//! where N is the data width as configured by SSIConfigSetExpClk(). For +//! example, if the interface is configured for 8-bit data width, the upper 24 +//! bits of \e ui32Data are discarded. +//! +//! \return Returns the number of elements written to the SSI transmit FIFO. +// +//***************************************************************************** +int32_t +SSIDataPutNonBlocking(uint32_t ui32Base, uint32_t ui32Data) +{ + // + // Check the arguments. + // + ASSERT(_SSIBaseValid(ui32Base)); + ASSERT((ui32Data & (0xfffffffe << (HWREG(ui32Base + SSI_O_CR0) & + SSI_CR0_DSS_M))) == 0); + + // + // Check for space to write. + // + if(HWREG(ui32Base + SSI_O_SR) & SSI_SR_TNF) + { + HWREG(ui32Base + SSI_O_DR) = ui32Data; + return(1); + } + else + { + return(0); + } +} + +//***************************************************************************** +// +//! Gets a data element from the SSI receive FIFO. +//! +//! \param ui32Base specifies the SSI module base address. +//! \param pui32Data is a pointer to a storage location for data that was +//! received over the SSI interface. +//! +//! This function gets received data from the receive FIFO of the specified +//! SSI module and places that data into the location specified by the +//! \e pui32Data parameter. If there is no data available, this function waits +//! until data is received before returning. +//! +//! \note Only the lower N bits of the value written to \e pui32Data contain +//! valid data, where N is the data width as configured by +//! SSIConfigSetExpClk(). For example, if the interface is configured for +//! 8-bit data width, only the lower 8 bits of the value written to +//! \e pui32Data contain valid data. +//! +//! \return None. +// +//***************************************************************************** +void +SSIDataGet(uint32_t ui32Base, uint32_t *pui32Data) +{ + // + // Check the arguments. + // + ASSERT(_SSIBaseValid(ui32Base)); + + // + // Wait until there is data to be read. + // + while(!(HWREG(ui32Base + SSI_O_SR) & SSI_SR_RNE)) + { + } + + // + // Read data from SSI. + // + *pui32Data = HWREG(ui32Base + SSI_O_DR); +} + +//***************************************************************************** +// +//! Gets a data element from the SSI receive FIFO. +//! +//! \param ui32Base specifies the SSI module base address. +//! \param pui32Data is a pointer to a storage location for data that was +//! received over the SSI interface. +//! +//! This function gets received data from the receive FIFO of the specified SSI +//! module and places that data into the location specified by the \e ui32Data +//! parameter. If there is no data in the FIFO, then this function returns a +//! zero. +//! +//! \note Only the lower N bits of the value written to \e pui32Data contain +//! valid data, where N is the data width as configured by +//! SSIConfigSetExpClk(). For example, if the interface is configured for +//! 8-bit data width, only the lower 8 bits of the value written to +//! \e pui32Data contain valid data. +//! +//! \return Returns the number of elements read from the SSI receive FIFO. +// +//***************************************************************************** +int32_t +SSIDataGetNonBlocking(uint32_t ui32Base, uint32_t *pui32Data) +{ + // + // Check the arguments. + // + ASSERT(_SSIBaseValid(ui32Base)); + + // + // Check for data to read. + // + if(HWREG(ui32Base + SSI_O_SR) & SSI_SR_RNE) + { + *pui32Data = HWREG(ui32Base + SSI_O_DR); + return(1); + } + else + { + return(0); + } +} + +//***************************************************************************** +// +//! Enables SSI DMA operation. +//! +//! \param ui32Base is the base address of the SSI module. +//! \param ui32DMAFlags is a bit mask of the DMA features to enable. +//! +//! This function enables the specified SSI DMA features. The SSI can be +//! configured to use DMA for transmit and/or receive data transfers. +//! The \e ui32DMAFlags parameter is the logical OR of any of the following +//! values: +//! +//! - SSI_DMA_RX - enable DMA for receive +//! - SSI_DMA_TX - enable DMA for transmit +//! +//! \note The uDMA controller must also be set up before DMA can be used +//! with the SSI. +//! +//! \return None. +// +//***************************************************************************** +void +SSIDMAEnable(uint32_t ui32Base, uint32_t ui32DMAFlags) +{ + // + // Check the arguments. + // + ASSERT(_SSIBaseValid(ui32Base)); + + // + // Set the requested bits in the SSI DMA control register. + // + HWREG(ui32Base + SSI_O_DMACTL) |= ui32DMAFlags; +} + +//***************************************************************************** +// +//! Disables SSI DMA operation. +//! +//! \param ui32Base is the base address of the SSI module. +//! \param ui32DMAFlags is a bit mask of the DMA features to disable. +//! +//! This function is used to disable SSI DMA features that were enabled +//! by SSIDMAEnable(). The specified SSI DMA features are disabled. The +//! \e ui32DMAFlags parameter is the logical OR of any of the following values: +//! +//! - SSI_DMA_RX - disable DMA for receive +//! - SSI_DMA_TX - disable DMA for transmit +//! +//! \return None. +// +//***************************************************************************** +void +SSIDMADisable(uint32_t ui32Base, uint32_t ui32DMAFlags) +{ + // + // Check the arguments. + // + ASSERT(_SSIBaseValid(ui32Base)); + + // + // Clear the requested bits in the SSI DMA control register. + // + HWREG(ui32Base + SSI_O_DMACTL) &= ~ui32DMAFlags; +} + +//***************************************************************************** +// +//! Determines whether the SSI transmitter is busy or not. +//! +//! \param ui32Base is the base address of the SSI module. +//! +//! This function allows the caller to determine whether all transmitted bytes +//! have cleared the transmitter hardware. If \b false is returned, then the +//! transmit FIFO is empty and all bits of the last transmitted word have left +//! the hardware shift register. +//! +//! \return Returns \b true if the SSI is transmitting or \b false if all +//! transmissions are complete. +// +//***************************************************************************** +bool +SSIBusy(uint32_t ui32Base) +{ + // + // Check the arguments. + // + ASSERT(_SSIBaseValid(ui32Base)); + + // + // Determine if the SSI is busy. + // + return((HWREG(ui32Base + SSI_O_SR) & SSI_SR_BSY) ? true : false); +} + +//***************************************************************************** +// +//! Sets the data clock source for the specified SSI peripheral. +//! +//! \param ui32Base is the base address of the SSI module. +//! \param ui32Source is the baud clock source for the SSI. +//! +//! This function allows the baud clock source for the SSI to be selected. +//! The possible clock source are the system clock (\b SSI_CLOCK_SYSTEM) or +//! the precision internal oscillator (\b SSI_CLOCK_PIOSC). +//! +//! Changing the baud clock source changes the data rate generated by the +//! SSI. Therefore, the data rate should be reconfigured after any change to +//! the SSI clock source. +//! +//! \note The ability to specify the SSI baud clock source varies with the +//! Tiva part and SSI in use. Please consult the data sheet for the part +//! in use to determine whether this support is available. +//! +//! \return None. +// +//***************************************************************************** +void +SSIClockSourceSet(uint32_t ui32Base, uint32_t ui32Source) +{ + // + // Check the arguments. + // + ASSERT(_SSIBaseValid(ui32Base)); + ASSERT((ui32Source == SSI_CLOCK_SYSTEM) || + (ui32Source == SSI_CLOCK_PIOSC)); + + // + // Set the SSI clock source. + // + HWREG(ui32Base + SSI_O_CC) = ui32Source; +} + +//***************************************************************************** +// +//! Gets the data clock source for the specified SSI peripheral. +//! +//! \param ui32Base is the base address of the SSI module. +//! +//! This function returns the data clock source for the specified SSI. +//! +//! \note The ability to specify the SSI data clock source varies with the +//! Tiva part and SSI in use. Please consult the data sheet for the part +//! in use to determine whether this support is available. +//! +//! \return Returns the current clock source, which is either +//! \b SSI_CLOCK_SYSTEM or \b SSI_CLOCK_PIOSC. +// +//***************************************************************************** +uint32_t +SSIClockSourceGet(uint32_t ui32Base) +{ + // + // Check the arguments. + // + ASSERT(_SSIBaseValid(ui32Base)); + + // + // Return the SSI clock source. + // + return(HWREG(ui32Base + SSI_O_CC)); +} + +//***************************************************************************** +// +//! Selects the advanced mode of operation for the SSI module. +//! +//! \param ui32Base is the base address of the SSI module. +//! \param ui32Mode is the mode of operation to use. +//! +//! This function selects the mode of operation for the SSI module, which is +//! needed when using the advanced operation modes (Bi- or Quad-SPI). One of +//! the following modes can be selected: +//! +//! - \b SSI_ADV_MODE_LEGACY - Disables the advanced modes of operation, +//! resulting in legacy, or backwards-compatible, operation. When this mode +//! is selected, it is not valid to switch to Bi- or Quad-SPI operation. +//! This mode is the default. +//! - \b SSI_ADV_MODE_WRITE - The advanced mode of operation where data is only +//! written to the slave; any data clocked in via the \b SSIRx pin is thrown +//! away (instead of being placed into the SSI Rx FIFO). +//! - \b SSI_ADV_MODE_READ_WRITE - The advanced mode of operation where data is +//! written to and read from the slave; this mode is the same as +//! \b SSI_ADV_MODE_LEGACY but allows transitions to Bi- or Quad-SPI +//! operation. +//! - \b SSI_ADV_MODE_BI_READ - The advanced mode of operation where data is +//! read from the slave in Bi-SPI mode, with two bits of data read on every +//! SSI clock. +//! - \b SSI_ADV_MODE_BI_WRITE - The advanced mode of operation where data is +//! written to the slave in Bi-SPI mode, with two bits of data written on +//! every SSI clock. +//! - \b SSI_ADV_MODE_QUAD_READ - The advanced mode of operation where data is +//! read from the slave in Quad-SPI mode, with four bits of data read on +//! every SSI clock. +//! - \b SSI_ADV_MODE_QUAD_WRITE - The advanced mode of operation where data is +//! written to the slave in Quad-SPI mode, with four bits of data written on +//! every SSI clock. +//! +//! The following mode transitions are valid (other transitions produce +//! undefined results): +//! +//! \verbatim +//! +----------+-------------------------------------------------------------+ +//! |FROM | TO | +//! | |Legacy|Write|Read Write|Bi Read|Bi Write|Quad Read|Quad Write| +//! +----------+------+-----+----------+-------+--------+---------+----------+ +//! |Legacy | yes | yes | yes | | | | | +//! |Write | yes | yes | yes | yes | yes | yes | yes | +//! |Read/Write| yes | yes | yes | yes | yes | yes | yes | +//! |Bi Read | | yes | yes | yes | yes | | | +//! |Bi write | | yes | yes | yes | yes | | | +//! |Quad read | | yes | yes | | | yes | yes | +//! |Quad write| | yes | yes | | | yes | yes | +//! +----------+------+-----+----------+-------+--------+---------+----------+ +//! \endverbatim +//! +//! When using an advanced mode of operation, the SSI module must have been +//! configured for eight data bits and the \b SSI_FRF_MOTO_MODE_0 protocol. +//! The advanced mode operation that is selected applies only to data newly +//! written into the FIFO; the data that is already present in the FIFO is +//! handled using the advanced mode of operation in effect when that data was +//! written. +//! +//! Switching into and out of legacy mode should only occur when the FIFO is +//! empty. +//! +//! \note The availability of the advanced mode of SSI operation varies with +//! the Tiva part and SSI in use. Please consult the data sheet for the +//! part in use to determine whether this support is available. +//! +//! \return None. +// +//***************************************************************************** +void +SSIAdvModeSet(uint32_t ui32Base, uint32_t ui32Mode) +{ + // + // Check the arguments. + // + ASSERT(_SSIBaseValid(ui32Base)); + ASSERT((ui32Mode == SSI_ADV_MODE_LEGACY) || + (ui32Mode == SSI_ADV_MODE_WRITE) || + (ui32Mode == SSI_ADV_MODE_READ_WRITE) || + (ui32Mode == SSI_ADV_MODE_BI_READ) || + (ui32Mode == SSI_ADV_MODE_BI_WRITE) || + (ui32Mode == SSI_ADV_MODE_QUAD_READ) || + (ui32Mode == SSI_ADV_MODE_QUAD_WRITE)); + + // + // Set the SSI mode of operation. + // + HWREG(ui32Base + SSI_O_CR1) = + ((HWREG(ui32Base + SSI_O_CR1) & ~(SSI_CR1_DIR | SSI_CR1_MODE_M)) | + ui32Mode); +} + +//***************************************************************************** +// +//! Puts a data element into the SSI transmit FIFO as the end of a frame. +//! +//! \param ui32Base specifies the SSI module base address. +//! \param ui32Data is the data to be transmitted over the SSI interface. +//! +//! This function places the supplied data into the transmit FIFO of the +//! specified SSI module, marking it as the end of a frame. If there is no +//! space available in the transmit FIFO, this function waits until there is +//! space available before returning. After this byte is transmitted by the +//! SSI module, the FSS signal de-asserts for at least one SSI clock. +//! +//! \note The upper 24 bits of \e ui32Data are discarded by the hardware. +//! +//! \note The availability of the advanced mode of SSI operation varies with +//! the Tiva part and SSI in use. Please consult the data sheet for the +//! part in use to determine whether this support is available. +//! +//! \return None. +// +//***************************************************************************** +void +SSIAdvDataPutFrameEnd(uint32_t ui32Base, uint32_t ui32Data) +{ + // + // Check the arguments. + // + ASSERT(_SSIBaseValid(ui32Base)); + ASSERT((ui32Data & 0xff) == 0); + + // + // Wait until there is space. + // + while(!(HWREG(ui32Base + SSI_O_SR) & SSI_SR_TNF)) + { + } + + // + // Write the data to the SSI. + // + HWREG(ui32Base + SSI_O_CR1) |= SSI_CR1_EOM; + HWREG(ui32Base + SSI_O_DR) = ui32Data; +} + +//***************************************************************************** +// +//! Puts a data element into the SSI transmit FIFO as the end of a frame. +//! +//! \param ui32Base specifies the SSI module base address. +//! \param ui32Data is the data to be transmitted over the SSI interface. +//! +//! This function places the supplied data into the transmit FIFO of the +//! specified SSI module, marking it as the end of a frame. After this byte is +//! transmitted by the SSI module, the FSS signal de-asserts for at least one +//! SSI clock. If there is no space in the FIFO, then this function returns a +//! zero. +//! +//! \note The upper 24 bits of \e ui32Data are discarded by the hardware. +//! +//! \note The availability of the advanced mode of SSI operation varies with +//! the Tiva part and SSI in use. Please consult the data sheet for the +//! part in use to determine whether this support is available. +//! +//! \return Returns the number of elements written to the SSI transmit FIFO. +// +//***************************************************************************** +int32_t +SSIAdvDataPutFrameEndNonBlocking(uint32_t ui32Base, uint32_t ui32Data) +{ + // + // Check the arguments. + // + ASSERT(_SSIBaseValid(ui32Base)); + ASSERT((ui32Data & 0xff) == 0); + + // + // Check for space to write. + // + if(HWREG(ui32Base + SSI_O_SR) & SSI_SR_TNF) + { + HWREG(ui32Base + SSI_O_CR1) |= SSI_CR1_EOM; + HWREG(ui32Base + SSI_O_DR) = ui32Data; + return(1); + } + else + { + return(0); + } +} + +//***************************************************************************** +// +//! Configures the SSI advanced mode to hold the SSIFss signal during the full +//! transfer. +//! +//! \param ui32Base is the base address of the SSI module. +//! +//! This function configures the SSI module to de-assert the SSIFss signal +//! during the entire data transfer when using one of the advanced modes +//! (instead of briefly de-asserting it after every byte). When using this +//! mode, SSIFss can be directly controlled via SSIAdvDataPutFrameEnd() and +//! SSIAdvDataPutFrameEndNonBlocking(). +//! +//! \note The availability of the advanced mode of SSI operation varies with +//! the Tiva part and SSI in use. Please consult the data sheet for the +//! part in use to determine whether this support is available. +//! +//! \return None. +// +//***************************************************************************** +void +SSIAdvFrameHoldEnable(uint32_t ui32Base) +{ + // + // Check the arguments. + // + ASSERT(_SSIBaseValid(ui32Base)); + + // + // Set the hold frame bit. + // + HWREG(ui32Base + SSI_O_CR1) |= SSI_CR1_FSSHLDFRM; +} + +//***************************************************************************** +// +//! Configures the SSI advanced mode to de-assert the SSIFss signal after every +//! byte transfer. +//! +//! \param ui32Base is the base address of the SSI module. +//! +//! This function configures the SSI module to de-assert the SSIFss signal +//! for one SSI clock cycle after every byte is transferred using one of the +//! advanced modes (instead of leaving it asserted for the entire transfer). +//! This mode is the default operation. +//! +//! \note The availability of the advanced mode of SSI operation varies with +//! the Tiva part and SSI in use. Please consult the data sheet for the +//! part in use to determine whether this support is available. +//! +//! \return None. +// +//***************************************************************************** +void +SSIAdvFrameHoldDisable(uint32_t ui32Base) +{ + // + // Check the arguments. + // + ASSERT(_SSIBaseValid(ui32Base)); + + // + // Clear the hold frame bit. + // + HWREG(ui32Base + SSI_O_CR1) &= ~(SSI_CR1_FSSHLDFRM); +} + +//***************************************************************************** +// +// Close the Doxygen group. +//! @} +// +//***************************************************************************** -- cgit v1.3.1