mbed-os

Fork of mbed-os by erkin yucel

Committer:
elessair
Date:
Sun Oct 23 15:10:02 2016 +0000
Revision:
0:f269e3021894
Initial commit

Who changed what in which revision?

UserRevisionLine numberNew contents of line
elessair 0:f269e3021894 1 /**
elessair 0:f269e3021894 2 ******************************************************************************
elessair 0:f269e3021894 3 * @file spi.c
elessair 0:f269e3021894 4 * @brief Implementation of a IPC 7207 SPI master driver
elessair 0:f269e3021894 5 * @internal
elessair 0:f269e3021894 6 * @author ON Semiconductor
elessair 0:f269e3021894 7 * @version $Rev: $
elessair 0:f269e3021894 8 * @date $Date: 2016-02-05 $
elessair 0:f269e3021894 9 ******************************************************************************
elessair 0:f269e3021894 10 * Copyright 2016 Semiconductor Components Industries LLC (d/b/a “ON Semiconductor”).
elessair 0:f269e3021894 11 * All rights reserved. This software and/or documentation is licensed by ON Semiconductor
elessair 0:f269e3021894 12 * under limited terms and conditions. The terms and conditions pertaining to the software
elessair 0:f269e3021894 13 * and/or documentation are available at http://www.onsemi.com/site/pdf/ONSEMI_T&C.pdf
elessair 0:f269e3021894 14 * (“ON Semiconductor Standard Terms and Conditions of Sale, Section 8 Software”) and
elessair 0:f269e3021894 15 * if applicable the software license agreement. Do not use this software and/or
elessair 0:f269e3021894 16 * documentation unless you have carefully read and you agree to the limited terms and
elessair 0:f269e3021894 17 * conditions. By using this software and/or documentation, you agree to the limited
elessair 0:f269e3021894 18 * terms and conditions.
elessair 0:f269e3021894 19 *
elessair 0:f269e3021894 20 * THIS SOFTWARE IS PROVIDED "AS IS". NO WARRANTIES, WHETHER EXPRESS, IMPLIED
elessair 0:f269e3021894 21 * OR STATUTORY, INCLUDING, BUT NOT LIMITED TO, IMPLIED WARRANTIES OF
elessair 0:f269e3021894 22 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE APPLY TO THIS SOFTWARE.
elessair 0:f269e3021894 23 * ON SEMICONDUCTOR SHALL NOT, IN ANY CIRCUMSTANCES, BE LIABLE FOR SPECIAL,
elessair 0:f269e3021894 24 * INCIDENTAL, OR CONSEQUENTIAL DAMAGES, FOR ANY REASON WHATSOEVER.
elessair 0:f269e3021894 25 * @endinternal
elessair 0:f269e3021894 26 *
elessair 0:f269e3021894 27 * @ingroup spi
elessair 0:f269e3021894 28 *
elessair 0:f269e3021894 29 * @details
elessair 0:f269e3021894 30 *
elessair 0:f269e3021894 31 */
elessair 0:f269e3021894 32 #if DEVICE_SPI
elessair 0:f269e3021894 33
elessair 0:f269e3021894 34 #include "spi.h"
elessair 0:f269e3021894 35 #include "clock.h"
elessair 0:f269e3021894 36 #include "objects.h"
elessair 0:f269e3021894 37 #include "spi_api.h"
elessair 0:f269e3021894 38 #include "PeripheralPins.h"
elessair 0:f269e3021894 39 #include "spi_ipc7207_map.h"
elessair 0:f269e3021894 40 #include "crossbar.h"
elessair 0:f269e3021894 41 #include "pad.h"
elessair 0:f269e3021894 42 #include "mbed_assert.h"
elessair 0:f269e3021894 43
elessair 0:f269e3021894 44 /** Initializes a spi device.
elessair 0:f269e3021894 45 * @details
elessair 0:f269e3021894 46 *
elessair 0:f269e3021894 47 * @param obj A spi device instance.
elessair 0:f269e3021894 48 * @param mosi pin to used as SPI MOSI
elessair 0:f269e3021894 49 * @param miso pin to used as SPI MISO
elessair 0:f269e3021894 50 * @param sclk pin to used as SPI SCLK
elessair 0:f269e3021894 51 * @return None
elessair 0:f269e3021894 52 */
elessair 0:f269e3021894 53 void fSpiInit(spi_t *obj, PinName mosi, PinName miso, PinName sclk, PinName ssel)
elessair 0:f269e3021894 54 {
elessair 0:f269e3021894 55 uint32_t clockDivisor;
elessair 0:f269e3021894 56
elessair 0:f269e3021894 57 /* determine the SPI to use */
elessair 0:f269e3021894 58 SPIName spi_mosi = (SPIName)pinmap_peripheral(mosi, PinMap_SPI_MOSI);
elessair 0:f269e3021894 59 SPIName spi_miso = (SPIName)pinmap_peripheral(miso, PinMap_SPI_MISO);
elessair 0:f269e3021894 60 SPIName spi_sclk = (SPIName)pinmap_peripheral(sclk, PinMap_SPI_SCLK);
elessair 0:f269e3021894 61 SPIName spi_ssel = (SPIName)pinmap_peripheral(ssel, PinMap_SPI_SSEL);
elessair 0:f269e3021894 62
elessair 0:f269e3021894 63 SPIName spi_data_1 = (SPIName)pinmap_merge(spi_mosi, spi_miso);
elessair 0:f269e3021894 64 SPIName spi_data_2 = (SPIName)pinmap_merge(spi_sclk, spi_ssel);
elessair 0:f269e3021894 65
elessair 0:f269e3021894 66 obj->membase = (SpiIpc7207Reg_pt)pinmap_merge(spi_data_1, spi_data_2);
elessair 0:f269e3021894 67 MBED_ASSERT((int)obj->membase != NC);
elessair 0:f269e3021894 68
elessair 0:f269e3021894 69 /* Check device to be activated */
elessair 0:f269e3021894 70 if(obj->membase == SPI1REG) {
elessair 0:f269e3021894 71 /* SPI 1 selected */
elessair 0:f269e3021894 72 CLOCK_ENABLE(CLOCK_SPI); /* Enable clock */
elessair 0:f269e3021894 73 } else {
elessair 0:f269e3021894 74 /* SPI 2 selected */
elessair 0:f269e3021894 75 CLOCK_ENABLE(CLOCK_SPI2); /* Enable clock */
elessair 0:f269e3021894 76 }
elessair 0:f269e3021894 77
elessair 0:f269e3021894 78 CLOCK_ENABLE(CLOCK_CROSSB);
elessair 0:f269e3021894 79 /* Cross bar setting: Map GPIOs to SPI */
elessair 0:f269e3021894 80 pinmap_pinout(sclk, PinMap_SPI_SCLK);
elessair 0:f269e3021894 81 pinmap_pinout(mosi, PinMap_SPI_MOSI);
elessair 0:f269e3021894 82
elessair 0:f269e3021894 83 /* Configure GPIO Direction */
elessair 0:f269e3021894 84 CLOCK_ENABLE(CLOCK_GPIO);
elessair 0:f269e3021894 85 GPIOREG->W_OUT |= ((True << sclk) | (True << mosi) | (True << ssel)); /* Set pins as output */
elessair 0:f269e3021894 86 GPIOREG->W_IN |= (True << miso); /* Set pin as input */
elessair 0:f269e3021894 87
elessair 0:f269e3021894 88 /* Pad settings */
elessair 0:f269e3021894 89 CLOCK_ENABLE(CLOCK_PAD);
elessair 0:f269e3021894 90 pin_mode(sclk, PushPullPullDown);
elessair 0:f269e3021894 91 pin_mode(mosi, PushPullPullDown);
elessair 0:f269e3021894 92
elessair 0:f269e3021894 93 /* PAD drive strength */
elessair 0:f269e3021894 94 PadReg_t *padRegOffset = (PadReg_t*)(PADREG_BASE + (sclk * PAD_REG_ADRS_BYTE_SIZE));
elessair 0:f269e3021894 95 padRegOffset->PADIO0.BITS.POWER = True; /* sclk: Drive strength */
elessair 0:f269e3021894 96 padRegOffset->PADIO1.BITS.POWER = True; /* mosi: Drive strength */
elessair 0:f269e3021894 97 if(miso != NC) {
elessair 0:f269e3021894 98 pinmap_pinout(miso, PinMap_SPI_MISO); /* Cross bar settings */
elessair 0:f269e3021894 99 pin_mode(miso, OpenDrainNoPull); /* Pad setting */
elessair 0:f269e3021894 100 padRegOffset->PADIO2.BITS.POWER = True; /* miso: Drive strength */
elessair 0:f269e3021894 101 }
elessair 0:f269e3021894 102 if(ssel != NC) {
elessair 0:f269e3021894 103 pinmap_pinout(ssel, PinMap_SPI_SSEL); /* Cross bar settings */
elessair 0:f269e3021894 104 pin_mode(ssel, PushPullPullUp); /* Pad setting */
elessair 0:f269e3021894 105 padRegOffset->PADIO3.BITS.POWER = True; /* ssel: Drive strength */
elessair 0:f269e3021894 106 SPI1REG->SLAVE_SELECT.BITS.SS_ENABLE = SPI_SLAVE_SELECT_NORM_BEHAVE; /* Slave select: Normal behavior */
elessair 0:f269e3021894 107 }
elessair 0:f269e3021894 108 CLOCK_DISABLE(CLOCK_PAD);
elessair 0:f269e3021894 109 CLOCK_DISABLE(CLOCK_GPIO);
elessair 0:f269e3021894 110 CLOCK_DISABLE(CLOCK_CROSSB);
elessair 0:f269e3021894 111
elessair 0:f269e3021894 112 /* disable/reset the spi port: Clear control register*/
elessair 0:f269e3021894 113 obj->membase->CONTROL.WORD = False;
elessair 0:f269e3021894 114
elessair 0:f269e3021894 115 /* set default baud rate to 1MHz */
elessair 0:f269e3021894 116 clockDivisor = ((fClockGetPeriphClockfrequency() / SPI_DEFAULT_SPEED) >> True) - True;
elessair 0:f269e3021894 117 obj->membase->FDIV = clockDivisor;
elessair 0:f269e3021894 118
elessair 0:f269e3021894 119 /* set tx/rx fifos watermarks */ /* TODO water mark level 1 byte ?*/
elessair 0:f269e3021894 120 obj->membase->TX_WATERMARK = True;
elessair 0:f269e3021894 121 obj->membase->RX_WATERMARK = True;
elessair 0:f269e3021894 122
elessair 0:f269e3021894 123 /* DIsable and clear IRQs */ /* TODO sync api, do not need irq ?*/
elessair 0:f269e3021894 124 obj->membase->IRQ_ENABLE = False;
elessair 0:f269e3021894 125 obj->membase->IRQ_CLEAR = SPI_BYTE_MASK; /* Clear all */
elessair 0:f269e3021894 126
elessair 0:f269e3021894 127 /* configure slave select */
elessair 0:f269e3021894 128 obj->membase->SLAVE_SELECT.WORD = SPI_SLAVE_SELECT_DEFAULT;
elessair 0:f269e3021894 129 obj->membase->SLAVE_SELECT_POLARITY = False;
elessair 0:f269e3021894 130
elessair 0:f269e3021894 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 */
elessair 0:f269e3021894 132 obj->membase->CONTROL.WORD = SPI_DEFAULT_CONFIG;
elessair 0:f269e3021894 133 }
elessair 0:f269e3021894 134
elessair 0:f269e3021894 135 /** Close a spi device.
elessair 0:f269e3021894 136 * @details
elessair 0:f269e3021894 137 *
elessair 0:f269e3021894 138 * @param obj The spi device to close.
elessair 0:f269e3021894 139 * @return None
elessair 0:f269e3021894 140 */
elessair 0:f269e3021894 141 void fSpiClose(spi_t *obj)
elessair 0:f269e3021894 142 {
elessair 0:f269e3021894 143 /* disable the spi port */
elessair 0:f269e3021894 144 obj->membase->CONTROL.BITS.ENABLE = False;
elessair 0:f269e3021894 145
elessair 0:f269e3021894 146 /* disable interruption associated with spi */
elessair 0:f269e3021894 147 NVIC_DisableIRQ(obj->irq);
elessair 0:f269e3021894 148 }
elessair 0:f269e3021894 149
elessair 0:f269e3021894 150 /**
elessair 0:f269e3021894 151 * Write data to an SPI device.
elessair 0:f269e3021894 152 * The data is written from the buffer into the transmit register.
elessair 0:f269e3021894 153 * This function blocks untill write and read happens.
elessair 0:f269e3021894 154 *
elessair 0:f269e3021894 155 * @param obj The device to write to.
elessair 0:f269e3021894 156 * @param buf The buffer to write from (the contents of the buffer may not be modified).
elessair 0:f269e3021894 157 * @return the value received during send
elessair 0:f269e3021894 158 */
elessair 0:f269e3021894 159 int fSpiWriteB(spi_t *obj, uint32_t const buf)
elessair 0:f269e3021894 160 {
elessair 0:f269e3021894 161 int byte;
elessair 0:f269e3021894 162
elessair 0:f269e3021894 163 while((obj->membase->STATUS.BITS.TX_FULL == True) && (obj->membase->STATUS.BITS.RX_FULL == True)); /* Wait till Tx/Rx status is full */
elessair 0:f269e3021894 164 obj->membase->TX_DATA = buf;
elessair 0:f269e3021894 165
elessair 0:f269e3021894 166 while (obj->membase->STATUS.BITS.RX_EMPTY == True); /* Wait till Receive status is empty */
elessair 0:f269e3021894 167 byte = obj->membase->RX_DATA;
elessair 0:f269e3021894 168 return byte;
elessair 0:f269e3021894 169 }
elessair 0:f269e3021894 170
elessair 0:f269e3021894 171 #endif /* DEVICE_SPI */