circuitpython/drivers/cc3000/src/ccspi.c

456 lines
15 KiB
C

/*****************************************************************************
*
* spi.c - CC3000 Host Driver Implementation.
* Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.com/
*
* 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.
*
*****************************************************************************/
#include <string.h>
#include "py/runtime.h"
#include "pin.h"
#include "led.h"
#include "extint.h"
#include "spi.h"
#include "ccspi.h"
#include "evnt_handler.h"
#if 0 // print debugging info
#include <stdio.h>
#define DEBUG_printf(args...) printf(args)
#else // don't print debugging info
#define DEBUG_printf(args...) (void)0
#endif
// these need to be set to valid values before anything in this file will work
STATIC const spi_t *SPI_HANDLE = NULL;
STATIC const pin_obj_t *PIN_CS = NULL;
STATIC const pin_obj_t *PIN_EN = NULL;
STATIC const pin_obj_t *PIN_IRQ = NULL;
#define CS_LOW() HAL_GPIO_WritePin(PIN_CS->gpio, PIN_CS->pin_mask, GPIO_PIN_RESET)
#define CS_HIGH() HAL_GPIO_WritePin(PIN_CS->gpio, PIN_CS->pin_mask, GPIO_PIN_SET)
#define READ 3
#define WRITE 1
#define HI(value) (((value) & 0xFF00) >> 8)
#define LO(value) ((value) & 0x00FF)
#define SPI_TIMEOUT (1000)
#define HEADERS_SIZE_EVNT (SPI_HEADER_SIZE + 5)
/* SPI bus states */
#define eSPI_STATE_POWERUP (0)
#define eSPI_STATE_INITIALIZED (1)
#define eSPI_STATE_IDLE (2)
#define eSPI_STATE_WRITE_IRQ (3)
#define eSPI_STATE_WRITE_FIRST_PORTION (4)
#define eSPI_STATE_WRITE_EOT (5)
#define eSPI_STATE_READ_IRQ (6)
#define eSPI_STATE_READ_FIRST_PORTION (7)
#define eSPI_STATE_READ_EOT (8)
// The magic number that resides at the end of the TX/RX buffer (1 byte after the allocated size)
// for the purpose of detection of the overrun. The location of the memory where the magic number
// resides shall never be written. In case it is written - the overrun occured and either recevie function
// or send function will stuck forever.
#define CC3000_BUFFER_MAGIC_NUMBER (0xDE)
typedef struct {
gcSpiHandleRx SPIRxHandler;
unsigned short usTxPacketLength;
unsigned short usRxPacketLength;
unsigned long ulSpiState;
unsigned char *pTxPacket;
unsigned char *pRxPacket;
} tSpiInformation;
STATIC tSpiInformation sSpiInformation;
STATIC char spi_buffer[CC3000_RX_BUFFER_SIZE];
unsigned char wlan_tx_buffer[CC3000_TX_BUFFER_SIZE];
STATIC const mp_obj_fun_builtin_fixed_t irq_callback_obj;
// set the pins to use to communicate with the CC3000
// the arguments must be of type pin_obj_t* and SPI_HandleTypeDef*
void SpiInit(void *spi, const void *pin_cs, const void *pin_en, const void *pin_irq) {
SPI_HANDLE = spi;
PIN_CS = pin_cs;
PIN_EN = pin_en;
PIN_IRQ = pin_irq;
}
void SpiClose(void)
{
if (sSpiInformation.pRxPacket) {
sSpiInformation.pRxPacket = 0;
}
tSLInformation.WlanInterruptDisable();
//HAL_SPI_DeInit(SPI_HANDLE);
}
void SpiOpen(gcSpiHandleRx pfRxHandler)
{
DEBUG_printf("SpiOpen\n");
/* initialize SPI state */
sSpiInformation.ulSpiState = eSPI_STATE_POWERUP;
sSpiInformation.SPIRxHandler = pfRxHandler;
sSpiInformation.usTxPacketLength = 0;
sSpiInformation.pTxPacket = NULL;
sSpiInformation.pRxPacket = (unsigned char *)spi_buffer;
sSpiInformation.usRxPacketLength = 0;
spi_buffer[CC3000_RX_BUFFER_SIZE - 1] = CC3000_BUFFER_MAGIC_NUMBER;
wlan_tx_buffer[CC3000_TX_BUFFER_SIZE - 1] = CC3000_BUFFER_MAGIC_NUMBER;
/* SPI configuration */
SPI_InitTypeDef *init = &SPI_HANDLE->spi->Init;
init->Mode = SPI_MODE_MASTER;
init->Direction = SPI_DIRECTION_2LINES;
init->DataSize = SPI_DATASIZE_8BIT;
init->CLKPolarity = SPI_POLARITY_LOW;
init->CLKPhase = SPI_PHASE_2EDGE;
init->NSS = SPI_NSS_SOFT;
init->BaudRatePrescaler = SPI_BAUDRATEPRESCALER_8;
init->FirstBit = SPI_FIRSTBIT_MSB;
init->TIMode = SPI_TIMODE_DISABLED;
init->CRCCalculation = SPI_CRCCALCULATION_DISABLED;
init->CRCPolynomial = 7;
spi_init(SPI_HANDLE, false);
// configure wlan CS and EN pins
GPIO_InitTypeDef GPIO_InitStructure;
GPIO_InitStructure.Speed = GPIO_SPEED_FAST;
GPIO_InitStructure.Mode = GPIO_MODE_OUTPUT_PP;
GPIO_InitStructure.Pull = GPIO_NOPULL;
GPIO_InitStructure.Alternate = 0;
GPIO_InitStructure.Pin = PIN_CS->pin_mask;
HAL_GPIO_Init(PIN_CS->gpio, &GPIO_InitStructure);
GPIO_InitStructure.Pin = PIN_EN->pin_mask;
HAL_GPIO_Init(PIN_EN->gpio, &GPIO_InitStructure);
HAL_GPIO_WritePin(PIN_CS->gpio, PIN_CS->pin_mask, GPIO_PIN_SET);
HAL_GPIO_WritePin(PIN_EN->gpio, PIN_EN->pin_mask, GPIO_PIN_RESET);
/* do a dummy read, this ensures SCLK is low before
actual communications start, it might be required */
CS_LOW();
uint8_t buf[1];
HAL_SPI_Receive(SPI_HANDLE->spi, buf, sizeof(buf), SPI_TIMEOUT);
CS_HIGH();
// register EXTI
extint_register((mp_obj_t)PIN_IRQ, GPIO_MODE_IT_FALLING, GPIO_PULLUP, (mp_obj_t)&irq_callback_obj, true);
extint_enable(PIN_IRQ->pin);
DEBUG_printf("SpiOpen finished; IRQ.pin=%d IRQ_LINE=%d\n", PIN_IRQ->pin, PIN_IRQ->pin);
}
long ReadWlanInterruptPin(void)
{
return HAL_GPIO_ReadPin(PIN_IRQ->gpio, PIN_IRQ->pin_mask);
}
void WriteWlanPin(unsigned char val)
{
HAL_GPIO_WritePin(PIN_EN->gpio, PIN_EN->pin_mask,
(WLAN_ENABLE)? GPIO_PIN_SET:GPIO_PIN_RESET);
}
STATIC void SpiWriteDataSynchronous(unsigned char *data, unsigned short size)
{
DEBUG_printf("SpiWriteDataSynchronous(data=%p [%x %x %x %x], size=%u)\n", data, data[0], data[1], data[2], data[3], size);
__disable_irq();
if (HAL_SPI_TransmitReceive(SPI_HANDLE->spi, data, data, size, SPI_TIMEOUT) != HAL_OK) {
//BREAK();
}
__enable_irq();
DEBUG_printf(" - rx data = [%x %x %x %x]\n", data[0], data[1], data[2], data[3]);
}
STATIC void SpiReadDataSynchronous(unsigned char *data, unsigned short size)
{
memset(data, READ, size);
__disable_irq();
if (HAL_SPI_TransmitReceive(SPI_HANDLE->spi, data, data, size, SPI_TIMEOUT) != HAL_OK) {
//BREAK();
}
__enable_irq();
}
STATIC void __delay_cycles(volatile int x)
{
x *= 6; // for 168 MHz CPU
while (x--);
}
STATIC long SpiFirstWrite(unsigned char *ucBuf, unsigned short usLength)
{
DEBUG_printf("SpiFirstWrite %lu\n", sSpiInformation.ulSpiState);
CS_LOW();
// Assuming we are running on 24 MHz ~50 micro delay is 1200 cycles;
__delay_cycles(1200);
// SPI writes first 4 bytes of data
SpiWriteDataSynchronous(ucBuf, 4);
__delay_cycles(1200);
SpiWriteDataSynchronous(ucBuf + 4, usLength - 4);
// From this point on - operate in a regular way
sSpiInformation.ulSpiState = eSPI_STATE_IDLE;
CS_HIGH();
return(0);
}
long SpiWrite(unsigned char *pUserBuffer, unsigned short usLength)
{
DEBUG_printf("SpiWrite %lu\n", sSpiInformation.ulSpiState);
unsigned char ucPad = 0;
// Figure out the total length of the packet in order to figure out if there
// is padding or not
if(!(usLength & 0x0001)) {
ucPad++;
}
pUserBuffer[0] = WRITE;
pUserBuffer[1] = HI(usLength + ucPad);
pUserBuffer[2] = LO(usLength + ucPad);
pUserBuffer[3] = 0;
pUserBuffer[4] = 0;
usLength += (SPI_HEADER_SIZE + ucPad);
// The magic number that resides at the end of the TX/RX buffer (1 byte after the allocated size)
// for the purpose of detection of the overrun. If the magic number is overriten - buffer overrun
// occurred - and we will stuck here forever!
if (wlan_tx_buffer[CC3000_TX_BUFFER_SIZE - 1] != CC3000_BUFFER_MAGIC_NUMBER) {
while (1);
}
if (sSpiInformation.ulSpiState == eSPI_STATE_POWERUP) {
while (sSpiInformation.ulSpiState != eSPI_STATE_INITIALIZED);
}
if (sSpiInformation.ulSpiState == eSPI_STATE_INITIALIZED) {
// This is time for first TX/RX transactions over SPI:
// the IRQ is down - so need to send read buffer size command
SpiFirstWrite(pUserBuffer, usLength);
} else {
//
// We need to prevent here race that can occur in case 2 back to back packets are sent to the
// device, so the state will move to IDLE and once again to not IDLE due to IRQ
//
tSLInformation.WlanInterruptDisable();
while (sSpiInformation.ulSpiState != eSPI_STATE_IDLE);
sSpiInformation.ulSpiState = eSPI_STATE_WRITE_IRQ;
sSpiInformation.pTxPacket = pUserBuffer;
sSpiInformation.usTxPacketLength = usLength;
// Assert the CS line and wait till SSI IRQ line is active and then initialize write operation
CS_LOW();
// Re-enable IRQ - if it was not disabled - this is not a problem...
tSLInformation.WlanInterruptEnable();
// check for a missing interrupt between the CS assertion and enabling back the interrupts
if (tSLInformation.ReadWlanInterruptPin() == 0) {
SpiWriteDataSynchronous(sSpiInformation.pTxPacket, sSpiInformation.usTxPacketLength);
sSpiInformation.ulSpiState = eSPI_STATE_IDLE;
CS_HIGH();
}
}
// Due to the fact that we are currently implementing a blocking situation
// here we will wait till end of transaction
while (eSPI_STATE_IDLE != sSpiInformation.ulSpiState);
return(0);
}
#if 0
unused
STATIC void SpiReadPacket(void)
{
int length;
/* read SPI header */
SpiReadDataSynchronous(sSpiInformation.pRxPacket, SPI_HEADER_SIZE);
/* parse data length */
STREAM_TO_UINT8(sSpiInformation.pRxPacket, SPI_HEADER_SIZE-1, length);
/* read the remainder of the packet */
SpiReadDataSynchronous(sSpiInformation.pRxPacket + SPI_HEADER_SIZE, length);
sSpiInformation.ulSpiState = eSPI_STATE_READ_EOT;
}
#endif
STATIC void SpiReadHeader(void)
{
SpiReadDataSynchronous(sSpiInformation.pRxPacket, 10);
}
STATIC void SpiTriggerRxProcessing(void)
{
SpiPauseSpi();
CS_HIGH();
// The magic number that resides at the end of the TX/RX buffer (1 byte after the allocated size)
// for the purpose of detection of the overrun. If the magic number is overriten - buffer overrun
// occurred - and we will stuck here forever!
if (sSpiInformation.pRxPacket[CC3000_RX_BUFFER_SIZE - 1] != CC3000_BUFFER_MAGIC_NUMBER) {
while (1);
}
sSpiInformation.ulSpiState = eSPI_STATE_IDLE;
sSpiInformation.SPIRxHandler(sSpiInformation.pRxPacket + SPI_HEADER_SIZE);
}
STATIC long SpiReadDataCont(void)
{
long data_to_recv=0;
unsigned char *evnt_buff, type;
//determine what type of packet we have
evnt_buff = sSpiInformation.pRxPacket;
STREAM_TO_UINT8((char *)(evnt_buff + SPI_HEADER_SIZE), HCI_PACKET_TYPE_OFFSET, type);
switch (type) {
case HCI_TYPE_DATA:{
// We need to read the rest of data..
STREAM_TO_UINT16((char *)(evnt_buff + SPI_HEADER_SIZE),
HCI_DATA_LENGTH_OFFSET, data_to_recv);
if (!((HEADERS_SIZE_EVNT + data_to_recv) & 1)) {
data_to_recv++;
}
if (data_to_recv) {
SpiReadDataSynchronous(evnt_buff + 10, data_to_recv);
}
break;
}
case HCI_TYPE_EVNT: {
// Calculate the rest length of the data
STREAM_TO_UINT8((char *)(evnt_buff + SPI_HEADER_SIZE),
HCI_EVENT_LENGTH_OFFSET, data_to_recv);
data_to_recv -= 1;
// Add padding byte if needed
if ((HEADERS_SIZE_EVNT + data_to_recv) & 1) {
data_to_recv++;
}
if (data_to_recv) {
SpiReadDataSynchronous(evnt_buff + 10, data_to_recv);
}
sSpiInformation.ulSpiState = eSPI_STATE_READ_EOT;
break;
}
}
return 0;
}
STATIC void SSIContReadOperation(void)
{
// The header was read - continue with the payload read
if (!SpiReadDataCont()) {
/* All the data was read - finalize handling by switching
to the task and calling from task Event Handler */
SpiTriggerRxProcessing();
}
}
STATIC mp_obj_t irq_callback(mp_obj_t line) {
DEBUG_printf("<< IRQ; state=%lu >>\n", sSpiInformation.ulSpiState);
switch (sSpiInformation.ulSpiState) {
case eSPI_STATE_POWERUP:
/* This means IRQ line was low call a callback of HCI Layer to inform on event */
DEBUG_printf(" - POWERUP\n");
sSpiInformation.ulSpiState = eSPI_STATE_INITIALIZED;
break;
case eSPI_STATE_IDLE:
DEBUG_printf(" - IDLE\n");
sSpiInformation.ulSpiState = eSPI_STATE_READ_IRQ;
/* IRQ line goes down - we are start reception */
CS_LOW();
// Wait for TX/RX Compete which will come as DMA interrupt
SpiReadHeader();
sSpiInformation.ulSpiState = eSPI_STATE_READ_EOT;
SSIContReadOperation();
break;
case eSPI_STATE_WRITE_IRQ:
DEBUG_printf(" - WRITE IRQ\n");
SpiWriteDataSynchronous(sSpiInformation.pTxPacket, sSpiInformation.usTxPacketLength);
sSpiInformation.ulSpiState = eSPI_STATE_IDLE;
CS_HIGH();
break;
}
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(irq_callback_obj, irq_callback);
void SpiPauseSpi(void) {
DEBUG_printf("SpiPauseSpi\n");
extint_disable(PIN_IRQ->pin);
}
void SpiResumeSpi(void) {
DEBUG_printf("SpiResumeSpi\n");
extint_enable(PIN_IRQ->pin);
}