mbed library sources. Supersedes mbed-src.

Fork of mbed-dev by Umar Naeem

Committer:
ranaumarnaeem
Date:
Tue May 23 12:54:50 2017 +0000
Revision:
165:2dd56e6daeec
Parent:
149:156823d33999
jhjg

Who changed what in which revision?

UserRevisionLine numberNew contents of line
<> 149:156823d33999 1 /**
<> 149:156823d33999 2 ******************************************************************************
<> 149:156823d33999 3 * @file spi.c
<> 149:156823d33999 4 * @brief Implementation of a IPC 7207 SPI master driver
<> 149:156823d33999 5 * @internal
<> 149:156823d33999 6 * @author ON Semiconductor
<> 149:156823d33999 7 * @version $Rev: $
<> 149:156823d33999 8 * @date $Date: 2016-02-05 $
<> 149:156823d33999 9 ******************************************************************************
<> 149:156823d33999 10 * Copyright 2016 Semiconductor Components Industries LLC (d/b/a “ON Semiconductor”).
<> 149:156823d33999 11 * All rights reserved. This software and/or documentation is licensed by ON Semiconductor
<> 149:156823d33999 12 * under limited terms and conditions. The terms and conditions pertaining to the software
<> 149:156823d33999 13 * and/or documentation are available at http://www.onsemi.com/site/pdf/ONSEMI_T&C.pdf
<> 149:156823d33999 14 * (“ON Semiconductor Standard Terms and Conditions of Sale, Section 8 Software”) and
<> 149:156823d33999 15 * if applicable the software license agreement. Do not use this software and/or
<> 149:156823d33999 16 * documentation unless you have carefully read and you agree to the limited terms and
<> 149:156823d33999 17 * conditions. By using this software and/or documentation, you agree to the limited
<> 149:156823d33999 18 * terms and conditions.
<> 149:156823d33999 19 *
<> 149:156823d33999 20 * THIS SOFTWARE IS PROVIDED "AS IS". NO WARRANTIES, WHETHER EXPRESS, IMPLIED
<> 149:156823d33999 21 * OR STATUTORY, INCLUDING, BUT NOT LIMITED TO, IMPLIED WARRANTIES OF
<> 149:156823d33999 22 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE APPLY TO THIS SOFTWARE.
<> 149:156823d33999 23 * ON SEMICONDUCTOR SHALL NOT, IN ANY CIRCUMSTANCES, BE LIABLE FOR SPECIAL,
<> 149:156823d33999 24 * INCIDENTAL, OR CONSEQUENTIAL DAMAGES, FOR ANY REASON WHATSOEVER.
<> 149:156823d33999 25 * @endinternal
<> 149:156823d33999 26 *
<> 149:156823d33999 27 * @ingroup spi
<> 149:156823d33999 28 *
<> 149:156823d33999 29 * @details
<> 149:156823d33999 30 *
<> 149:156823d33999 31 */
<> 149:156823d33999 32 #if DEVICE_SPI
<> 149:156823d33999 33
<> 149:156823d33999 34 #include "spi.h"
<> 149:156823d33999 35 #include "clock.h"
<> 149:156823d33999 36 #include "objects.h"
<> 149:156823d33999 37 #include "spi_api.h"
<> 149:156823d33999 38 #include "PeripheralPins.h"
<> 149:156823d33999 39 #include "spi_ipc7207_map.h"
<> 149:156823d33999 40 #include "crossbar.h"
<> 149:156823d33999 41 #include "pad.h"
<> 149:156823d33999 42 #include "mbed_assert.h"
<> 149:156823d33999 43
<> 149:156823d33999 44 /** Initializes a spi device.
<> 149:156823d33999 45 * @details
<> 149:156823d33999 46 *
<> 149:156823d33999 47 * @param obj A spi device instance.
<> 149:156823d33999 48 * @param mosi pin to used as SPI MOSI
<> 149:156823d33999 49 * @param miso pin to used as SPI MISO
<> 149:156823d33999 50 * @param sclk pin to used as SPI SCLK
<> 149:156823d33999 51 * @return None
<> 149:156823d33999 52 */
<> 149:156823d33999 53 void fSpiInit(spi_t *obj, PinName mosi, PinName miso, PinName sclk, PinName ssel)
<> 149:156823d33999 54 {
<> 149:156823d33999 55 uint32_t clockDivisor;
<> 149:156823d33999 56
<> 149:156823d33999 57 /* determine the SPI to use */
<> 149:156823d33999 58 SPIName spi_mosi = (SPIName)pinmap_peripheral(mosi, PinMap_SPI_MOSI);
<> 149:156823d33999 59 SPIName spi_miso = (SPIName)pinmap_peripheral(miso, PinMap_SPI_MISO);
<> 149:156823d33999 60 SPIName spi_sclk = (SPIName)pinmap_peripheral(sclk, PinMap_SPI_SCLK);
<> 149:156823d33999 61 SPIName spi_ssel = (SPIName)pinmap_peripheral(ssel, PinMap_SPI_SSEL);
<> 149:156823d33999 62
<> 149:156823d33999 63 SPIName spi_data_1 = (SPIName)pinmap_merge(spi_mosi, spi_miso);
<> 149:156823d33999 64 SPIName spi_data_2 = (SPIName)pinmap_merge(spi_sclk, spi_ssel);
<> 149:156823d33999 65
<> 149:156823d33999 66 obj->membase = (SpiIpc7207Reg_pt)pinmap_merge(spi_data_1, spi_data_2);
<> 149:156823d33999 67 MBED_ASSERT((int)obj->membase != NC);
<> 149:156823d33999 68
<> 149:156823d33999 69 /* Check device to be activated */
<> 149:156823d33999 70 if(obj->membase == SPI1REG) {
<> 149:156823d33999 71 /* SPI 1 selected */
<> 149:156823d33999 72 CLOCK_ENABLE(CLOCK_SPI); /* Enable clock */
<> 149:156823d33999 73 } else {
<> 149:156823d33999 74 /* SPI 2 selected */
<> 149:156823d33999 75 CLOCK_ENABLE(CLOCK_SPI2); /* Enable clock */
<> 149:156823d33999 76 }
<> 149:156823d33999 77
<> 149:156823d33999 78 CLOCK_ENABLE(CLOCK_CROSSB);
<> 149:156823d33999 79 /* Cross bar setting: Map GPIOs to SPI */
<> 149:156823d33999 80 pinmap_pinout(sclk, PinMap_SPI_SCLK);
<> 149:156823d33999 81 pinmap_pinout(mosi, PinMap_SPI_MOSI);
<> 149:156823d33999 82
<> 149:156823d33999 83 /* Configure GPIO Direction */
<> 149:156823d33999 84 CLOCK_ENABLE(CLOCK_GPIO);
<> 149:156823d33999 85 GPIOREG->W_OUT |= ((True << sclk) | (True << mosi) | (True << ssel)); /* Set pins as output */
<> 149:156823d33999 86 GPIOREG->W_IN |= (True << miso); /* Set pin as input */
<> 149:156823d33999 87
<> 149:156823d33999 88 /* Pad settings */
<> 149:156823d33999 89 CLOCK_ENABLE(CLOCK_PAD);
<> 149:156823d33999 90 pin_mode(sclk, PushPullPullDown);
<> 149:156823d33999 91 pin_mode(mosi, PushPullPullDown);
<> 149:156823d33999 92
<> 149:156823d33999 93 /* PAD drive strength */
<> 149:156823d33999 94 PadReg_t *padRegOffset = (PadReg_t*)(PADREG_BASE + (sclk * PAD_REG_ADRS_BYTE_SIZE));
<> 149:156823d33999 95 padRegOffset->PADIO0.BITS.POWER = True; /* sclk: Drive strength */
<> 149:156823d33999 96 padRegOffset->PADIO1.BITS.POWER = True; /* mosi: Drive strength */
<> 149:156823d33999 97 if(miso != NC) {
<> 149:156823d33999 98 pinmap_pinout(miso, PinMap_SPI_MISO); /* Cross bar settings */
<> 149:156823d33999 99 pin_mode(miso, OpenDrainNoPull); /* Pad setting */
<> 149:156823d33999 100 padRegOffset->PADIO2.BITS.POWER = True; /* miso: Drive strength */
<> 149:156823d33999 101 }
<> 149:156823d33999 102 if(ssel != NC) {
<> 149:156823d33999 103 pinmap_pinout(ssel, PinMap_SPI_SSEL); /* Cross bar settings */
<> 149:156823d33999 104 pin_mode(ssel, PushPullPullUp); /* Pad setting */
<> 149:156823d33999 105 padRegOffset->PADIO3.BITS.POWER = True; /* ssel: Drive strength */
<> 149:156823d33999 106 SPI1REG->SLAVE_SELECT.BITS.SS_ENABLE = SPI_SLAVE_SELECT_NORM_BEHAVE; /* Slave select: Normal behavior */
<> 149:156823d33999 107 }
<> 149:156823d33999 108 CLOCK_DISABLE(CLOCK_PAD);
<> 149:156823d33999 109 CLOCK_DISABLE(CLOCK_GPIO);
<> 149:156823d33999 110 CLOCK_DISABLE(CLOCK_CROSSB);
<> 149:156823d33999 111
<> 149:156823d33999 112 /* disable/reset the spi port: Clear control register*/
<> 149:156823d33999 113 obj->membase->CONTROL.WORD = False;
<> 149:156823d33999 114
<> 149:156823d33999 115 /* set default baud rate to 1MHz */
<> 149:156823d33999 116 clockDivisor = ((fClockGetPeriphClockfrequency() / SPI_DEFAULT_SPEED) >> True) - True;
<> 149:156823d33999 117 obj->membase->FDIV = clockDivisor;
<> 149:156823d33999 118
<> 149:156823d33999 119 /* set tx/rx fifos watermarks */ /* TODO water mark level 1 byte ?*/
<> 149:156823d33999 120 obj->membase->TX_WATERMARK = True;
<> 149:156823d33999 121 obj->membase->RX_WATERMARK = True;
<> 149:156823d33999 122
<> 149:156823d33999 123 /* DIsable and clear IRQs */ /* TODO sync api, do not need irq ?*/
<> 149:156823d33999 124 obj->membase->IRQ_ENABLE = False;
<> 149:156823d33999 125 obj->membase->IRQ_CLEAR = SPI_BYTE_MASK; /* Clear all */
<> 149:156823d33999 126
<> 149:156823d33999 127 /* configure slave select */
<> 149:156823d33999 128 obj->membase->SLAVE_SELECT.WORD = SPI_SLAVE_SELECT_DEFAULT;
<> 149:156823d33999 129 obj->membase->SLAVE_SELECT_POLARITY = False;
<> 149:156823d33999 130
<> 149:156823d33999 131 /* Configure control register parameters: 8 bits, master, CPOL = 0, Idle low. CPHA = 0, First transmit occurs before first edge of SCLK. MSB first. Sample incoming data on opposite edge of SCLK from when outgoing data is driven. enable the spi port */
<> 149:156823d33999 132 obj->membase->CONTROL.WORD = SPI_DEFAULT_CONFIG;
<> 149:156823d33999 133 }
<> 149:156823d33999 134
<> 149:156823d33999 135 /** Close a spi device.
<> 149:156823d33999 136 * @details
<> 149:156823d33999 137 *
<> 149:156823d33999 138 * @param obj The spi device to close.
<> 149:156823d33999 139 * @return None
<> 149:156823d33999 140 */
<> 149:156823d33999 141 void fSpiClose(spi_t *obj)
<> 149:156823d33999 142 {
<> 149:156823d33999 143 /* disable the spi port */
<> 149:156823d33999 144 obj->membase->CONTROL.BITS.ENABLE = False;
<> 149:156823d33999 145
<> 149:156823d33999 146 /* disable interruption associated with spi */
<> 149:156823d33999 147 NVIC_DisableIRQ(obj->irq);
<> 149:156823d33999 148 }
<> 149:156823d33999 149
<> 149:156823d33999 150 /**
<> 149:156823d33999 151 * Write data to an SPI device.
<> 149:156823d33999 152 * The data is written from the buffer into the transmit register.
<> 149:156823d33999 153 * This function blocks untill write and read happens.
<> 149:156823d33999 154 *
<> 149:156823d33999 155 * @param obj The device to write to.
<> 149:156823d33999 156 * @param buf The buffer to write from (the contents of the buffer may not be modified).
<> 149:156823d33999 157 * @return the value received during send
<> 149:156823d33999 158 */
<> 149:156823d33999 159 int fSpiWriteB(spi_t *obj, uint32_t const buf)
<> 149:156823d33999 160 {
<> 149:156823d33999 161 int byte;
<> 149:156823d33999 162
<> 149:156823d33999 163 while((obj->membase->STATUS.BITS.TX_FULL == True) && (obj->membase->STATUS.BITS.RX_FULL == True)); /* Wait till Tx/Rx status is full */
<> 149:156823d33999 164 obj->membase->TX_DATA = buf;
<> 149:156823d33999 165
<> 149:156823d33999 166 while (obj->membase->STATUS.BITS.RX_EMPTY == True); /* Wait till Receive status is empty */
<> 149:156823d33999 167 byte = obj->membase->RX_DATA;
<> 149:156823d33999 168 return byte;
<> 149:156823d33999 169 }
<> 149:156823d33999 170
<> 149:156823d33999 171 #endif /* DEVICE_SPI */