2015-11-10 10:56:17 -06:00

312 lines
12 KiB
C

/*
* This file is part of Espruino, a JavaScript interpreter for Microcontrollers
*
* Copyright (c) 2015 David Ogilvy (MetalPhreak)
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*
* ----------------------------------------------------------------------------
* This file is designed to be parsed during the build process
*
* Contains ESP8266 board specific functions.
* ----------------------------------------------------------------------------
*/
/**
* The Github project from which this source file came from can be found
* at: https://github.com/MetalPhreak/ESP8266_SPI_Driver
*/
#include "spi.h"
////////////////////////////////////////////////////////////////////////////////
//
// Function Name: spi_init
// Description: Wrapper to setup HSPI/SPI GPIO pins and default SPI clock
// Parameters: spi_no - SPI (0) or HSPI (1)
//
////////////////////////////////////////////////////////////////////////////////
void spi_init(uint8 spi_no){
if(spi_no > 1) return; //Only SPI and HSPI are valid spi modules.
spi_init_gpio(spi_no, SPI_CLK_USE_DIV);
spi_clock(spi_no, SPI_CLK_PREDIV, SPI_CLK_CNTDIV);
spi_tx_byte_order(spi_no, SPI_BYTE_ORDER_HIGH_TO_LOW);
spi_rx_byte_order(spi_no, SPI_BYTE_ORDER_HIGH_TO_LOW);
SET_PERI_REG_MASK(SPI_USER(spi_no), SPI_CS_SETUP|SPI_CS_HOLD);
CLEAR_PERI_REG_MASK(SPI_USER(spi_no), SPI_FLASH_MODE);
}
////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////
//
// Function Name: spi_init_gpio
// Description: Initialises the GPIO pins for use as SPI pins.
// Parameters: spi_no - SPI (0) or HSPI (1)
// sysclk_as_spiclk - SPI_CLK_80MHZ_NODIV (1) if using 80MHz
// sysclock for SPI clock.
// SPI_CLK_USE_DIV (0) if using divider to
// get lower SPI clock speed.
//
////////////////////////////////////////////////////////////////////////////////
void spi_init_gpio(uint8 spi_no, uint8 sysclk_as_spiclk){
// if(spi_no > 1) return; //Not required. Valid spi_no is checked with if/elif below.
uint32 clock_div_flag = 0;
if(sysclk_as_spiclk){
clock_div_flag = 0x0001;
}
if(spi_no==SPI){
WRITE_PERI_REG(PERIPHS_IO_MUX, 0x005|(clock_div_flag<<8)); //Set bit 8 if 80MHz sysclock required
PIN_FUNC_SELECT(PERIPHS_IO_MUX_SD_CLK_U, 1);
PIN_FUNC_SELECT(PERIPHS_IO_MUX_SD_CMD_U, 1);
PIN_FUNC_SELECT(PERIPHS_IO_MUX_SD_DATA0_U, 1);
PIN_FUNC_SELECT(PERIPHS_IO_MUX_SD_DATA1_U, 1);
}else if(spi_no==HSPI){
WRITE_PERI_REG(PERIPHS_IO_MUX, 0x105|(clock_div_flag<<9)); //Set bit 9 if 80MHz sysclock required
PIN_FUNC_SELECT(PERIPHS_IO_MUX_MTDI_U, 2); //GPIO12 is HSPI MISO pin (Master Data In)
PIN_FUNC_SELECT(PERIPHS_IO_MUX_MTCK_U, 2); //GPIO13 is HSPI MOSI pin (Master Data Out)
PIN_FUNC_SELECT(PERIPHS_IO_MUX_MTMS_U, 2); //GPIO14 is HSPI CLK pin (Clock)
PIN_FUNC_SELECT(PERIPHS_IO_MUX_MTDO_U, 2); //GPIO15 is HSPI CS pin (Chip Select / Slave Select)
}
}
////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////
//
// Function Name: spi_clock
// Description: sets up the control registers for the SPI clock
// Parameters: spi_no - SPI (0) or HSPI (1)
// prediv - predivider value (actual division value)
// cntdiv - postdivider value (actual division value)
// Set either divider to 0 to disable all division (80MHz sysclock)
//
////////////////////////////////////////////////////////////////////////////////
void spi_clock(uint8 spi_no, uint16 prediv, uint8 cntdiv){
if(spi_no > 1) return;
if((prediv==0)|(cntdiv==0)){
WRITE_PERI_REG(SPI_CLOCK(spi_no), SPI_CLK_EQU_SYSCLK);
} else {
WRITE_PERI_REG(SPI_CLOCK(spi_no),
(((prediv-1)&SPI_CLKDIV_PRE)<<SPI_CLKDIV_PRE_S)|
(((cntdiv-1)&SPI_CLKCNT_N)<<SPI_CLKCNT_N_S)|
(((cntdiv>>1)&SPI_CLKCNT_H)<<SPI_CLKCNT_H_S)|
((0&SPI_CLKCNT_L)<<SPI_CLKCNT_L_S));
}
}
////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////
//
// Function Name: spi_tx_byte_order
// Description: Setup the byte order for shifting data out of buffer
// Parameters: spi_no - SPI (0) or HSPI (1)
// byte_order - SPI_BYTE_ORDER_HIGH_TO_LOW (1)
// Data is sent out starting with Bit31 and down to Bit0
//
// SPI_BYTE_ORDER_LOW_TO_HIGH (0)
// Data is sent out starting with the lowest BYTE, from
// MSB to LSB, followed by the second lowest BYTE, from
// MSB to LSB, followed by the second highest BYTE, from
// MSB to LSB, followed by the highest BYTE, from MSB to LSB
// 0xABCDEFGH would be sent as 0xGHEFCDAB
//
//
////////////////////////////////////////////////////////////////////////////////
void spi_tx_byte_order(uint8 spi_no, uint8 byte_order){
if(spi_no > 1) return;
if(byte_order){
SET_PERI_REG_MASK(SPI_USER(spi_no), SPI_WR_BYTE_ORDER);
} else {
CLEAR_PERI_REG_MASK(SPI_USER(spi_no), SPI_WR_BYTE_ORDER);
}
}
////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////
//
// Function Name: spi_rx_byte_order
// Description: Setup the byte order for shifting data into buffer
// Parameters: spi_no - SPI (0) or HSPI (1)
// byte_order - SPI_BYTE_ORDER_HIGH_TO_LOW (1)
// Data is read in starting with Bit31 and down to Bit0
//
// SPI_BYTE_ORDER_LOW_TO_HIGH (0)
// Data is read in starting with the lowest BYTE, from
// MSB to LSB, followed by the second lowest BYTE, from
// MSB to LSB, followed by the second highest BYTE, from
// MSB to LSB, followed by the highest BYTE, from MSB to LSB
// 0xABCDEFGH would be read as 0xGHEFCDAB
//
//
////////////////////////////////////////////////////////////////////////////////
void spi_rx_byte_order(uint8 spi_no, uint8 byte_order){
if(spi_no > 1) return;
if(byte_order){
SET_PERI_REG_MASK(SPI_USER(spi_no), SPI_RD_BYTE_ORDER);
} else {
CLEAR_PERI_REG_MASK(SPI_USER(spi_no), SPI_RD_BYTE_ORDER);
}
}
////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////
//
// Function Name: spi_transaction
// Description: SPI transaction function
// Parameters: spi_no - SPI (0) or HSPI (1)
// cmd_bits - actual number of bits to transmit
// cmd_data - command data
// addr_bits - actual number of bits to transmit
// addr_data - address data
// dout_bits - actual number of bits to transmit
// dout_data - output data
// din_bits - actual number of bits to receive
//
// Returns: read data - uint32 containing read in data only if RX was set
// 0 - something went wrong (or actual read data was 0)
// 1 - data sent ok (or actual read data is 1)
// Note: all data is assumed to be stored in the lower bits of
// the data variables (for anything <32 bits).
//
////////////////////////////////////////////////////////////////////////////////
uint32 spi_transaction(uint8 spi_no, uint8 cmd_bits, uint16 cmd_data, uint32 addr_bits, uint32 addr_data, uint32 dout_bits, uint32 dout_data,
uint32 din_bits, uint32 dummy_bits){
if(spi_no > 1) return 0; //Check for a valid SPI
//code for custom Chip Select as GPIO PIN here
while(spi_busy(spi_no)); //wait for SPI to be ready
//########## Enable SPI Functions ##########//
//disable MOSI, MISO, ADDR, COMMAND, DUMMY in case previously set.
CLEAR_PERI_REG_MASK(SPI_USER(spi_no), SPI_USR_MOSI|SPI_USR_MISO|SPI_USR_COMMAND|SPI_USR_ADDR|SPI_USR_DUMMY);
//enable functions based on number of bits. 0 bits = disabled.
//This is rather inefficient but allows for a very generic function.
//CMD ADDR and MOSI are set below to save on an extra if statement.
// if(cmd_bits) {SET_PERI_REG_MASK(SPI_USER(spi_no), SPI_USR_COMMAND);}
// if(addr_bits) {SET_PERI_REG_MASK(SPI_USER(spi_no), SPI_USR_ADDR);}
if(din_bits) {SET_PERI_REG_MASK(SPI_USER(spi_no), SPI_USR_MISO);}
if(dummy_bits) {SET_PERI_REG_MASK(SPI_USER(spi_no), SPI_USR_DUMMY);}
//########## END SECTION ##########//
//########## Setup Bitlengths ##########//
WRITE_PERI_REG(SPI_USER1(spi_no), ((addr_bits-1)&SPI_USR_ADDR_BITLEN)<<SPI_USR_ADDR_BITLEN_S | //Number of bits in Address
((dout_bits-1)&SPI_USR_MOSI_BITLEN)<<SPI_USR_MOSI_BITLEN_S | //Number of bits to Send
((din_bits-1)&SPI_USR_MISO_BITLEN)<<SPI_USR_MISO_BITLEN_S | //Number of bits to receive
((dummy_bits-1)&SPI_USR_DUMMY_CYCLELEN)<<SPI_USR_DUMMY_CYCLELEN_S); //Number of Dummy bits to insert
//########## END SECTION ##########//
//########## Setup Command Data ##########//
if(cmd_bits) {
SET_PERI_REG_MASK(SPI_USER(spi_no), SPI_USR_COMMAND); //enable COMMAND function in SPI module
uint16 command = cmd_data << (16-cmd_bits); //align command data to high bits
command = ((command>>8)&0xff) | ((command<<8)&0xff00); //swap byte order
WRITE_PERI_REG(SPI_USER2(spi_no), ((((cmd_bits-1)&SPI_USR_COMMAND_BITLEN)<<SPI_USR_COMMAND_BITLEN_S) | command&SPI_USR_COMMAND_VALUE));
}
//########## END SECTION ##########//
//########## Setup Address Data ##########//
if(addr_bits){
SET_PERI_REG_MASK(SPI_USER(spi_no), SPI_USR_ADDR); //enable ADDRess function in SPI module
WRITE_PERI_REG(SPI_ADDR(spi_no), addr_data<<(32-addr_bits)); //align address data to high bits
}
//########## END SECTION ##########//
//########## Setup DOUT data ##########//
if(dout_bits) {
SET_PERI_REG_MASK(SPI_USER(spi_no), SPI_USR_MOSI); //enable MOSI function in SPI module
//copy data to W0
if(READ_PERI_REG(SPI_USER(spi_no))&SPI_WR_BYTE_ORDER) {
WRITE_PERI_REG(SPI_W0(spi_no), dout_data<<(32-dout_bits));
} else {
uint8 dout_extra_bits = dout_bits%8;
if(dout_extra_bits){
//if your data isn't a byte multiple (8/16/24/32 bits)and you don't have SPI_WR_BYTE_ORDER set, you need this to move the non-8bit remainder to the MSBs
//not sure if there's even a use case for this, but it's here if you need it...
//for example, 0xDA4 12 bits without SPI_WR_BYTE_ORDER would usually be output as if it were 0x0DA4,
//of which 0xA4, and then 0x0 would be shifted out (first 8 bits of low byte, then 4 MSB bits of high byte - ie reverse byte order).
//The code below shifts it out as 0xA4 followed by 0xD as you might require.
WRITE_PERI_REG(SPI_W0(spi_no), ((0xFFFFFFFF<<(dout_bits - dout_extra_bits)&dout_data)<<(8-dout_extra_bits) | (0xFFFFFFFF>>(32-(dout_bits - dout_extra_bits)))&dout_data));
} else {
WRITE_PERI_REG(SPI_W0(spi_no), dout_data);
}
}
}
//########## END SECTION ##########//
//########## Begin SPI Transaction ##########//
SET_PERI_REG_MASK(SPI_CMD(spi_no), SPI_USR);
//########## END SECTION ##########//
//########## Return DIN data ##########//
if(din_bits) {
while(spi_busy(spi_no)); //wait for SPI transaction to complete
if(READ_PERI_REG(SPI_USER(spi_no))&SPI_RD_BYTE_ORDER) {
return READ_PERI_REG(SPI_W0(spi_no)) >> (32-din_bits); //Assuming data in is written to MSB. TBC
} else {
return READ_PERI_REG(SPI_W0(spi_no)); //Read in the same way as DOUT is sent. Note existing contents of SPI_W0 remain unless overwritten!
}
return 0; //something went wrong
}
//########## END SECTION ##########//
//Transaction completed
return 1; //success
}
////////////////////////////////////////////////////////////////////////////////
/*///////////////////////////////////////////////////////////////////////////////
//
// Function Name: func
// Description:
// Parameters:
//
////////////////////////////////////////////////////////////////////////////////
void func(params){
}
///////////////////////////////////////////////////////////////////////////////*/