/** **************************************************************************************** * * @file spi_mouse.c * * @brief 3-wire SPI low level driver. * * Copyright (C) 2012. Dialog Semiconductor Ltd, unpublished work. This computer * program includes Confidential, Proprietary Information and is a Trade Secret of * Dialog Semiconductor Ltd. All use, disclosure, and/or reproduction is prohibited * unless authorized in writing. All Rights Reserved. * * and contributors. * **************************************************************************************** */ #include #include "global_io.h" #include "gpio.h" #include "spi_3wire.h" #include "arch_sleep.h" uint16_t TsradCounter; SPI_Pin sdio; SPI_Pin cs; /** **************************************************************************************** * @brief Initialize communication with the 3-wire SPI * @param[in] spi_sdio_pin_register: Size of the data to be read * @param[in] TsradCounterToSet: Counter for the delay between Address and Data phase in reading * **************************************************************************************** */ void initialize_3wire_spi(struct SPI_Config *cfg, bool enable_interrupt, uint16_t TsradCounterToSet) { sdio.port = cfg->sdio.port; // initialize with param data; sdio.pin = cfg->sdio.pin; cs.port = cfg->cs.port; cs.pin = cfg->cs.pin; //configure pins GPIO_ConfigurePin( cfg->cs.port, cfg->cs.pin, OUTPUT, PID_SPI_EN, true); GPIO_SetPinFunction( cfg->sdio.port, cfg->sdio.pin, INPUT, PID_SPI_DI); GPIO_SetPinFunction( cfg->clk.port, cfg->clk.pin, OUTPUT, PID_SPI_CLK); TsradCounter = TsradCounterToSet; // SPI read address-data delay (refer to sensor datasheet) // init SPI SetBits16(CLK_PER_REG, SPI_ENABLE, 1); // enable clock for SPI SetBits16(SPI_CTRL_REG,SPI_ON,0); // close SPI block, if opened SetBits16(SPI_CTRL_REG,SPI_WORD, cfg->SPI_Word_Mode); // SPI word mode SetBits16(SPI_CTRL_REG,SPI_SMN, cfg->SPI_Role); // SPI master mode SetBits16(SPI_CTRL_REG,SPI_POL, cfg->SPI_Polarity_Mode); // SPI mode selection - polarity SetBits16(SPI_CTRL_REG,SPI_PHA, cfg->SPI_PHA_Mode); // SPI mode selection - phase SetBits16(SPI_CTRL_REG,SPI_MINT, cfg->SPI_MINT_Mode); // disable SPI interrupt to the ICU SetBits16(SPI_CTRL_REG,SPI_CLK, cfg->SPI_XTAL_Freq); // SPI block clock divider SetBits16(SPI_CTRL_REG,SPI_ON, 1); // enable SPI block if (enable_interrupt) NVIC_EnableIRQ(SPI_IRQn); // enable SPI interrupt, if MINT is '1' and enable_interrupt is set } /** **************************************************************************************** * @brief Deactivate communication with the 3-wire SPI **************************************************************************************** */ void deactivate_3wire_spi(void) { GPIO_SetActive(cs.port, cs.pin); // leave CS high GPIO_SetPinFunction( sdio.port, sdio.pin, INPUT, PID_SPI_DI); NVIC_DisableIRQ(SPI_IRQn); // disable SPI interrupt SetBits16(SPI_CTRL_REG, SPI_ON, 0); // close SPI block, if opened SetBits16(CLK_PER_REG, SPI_ENABLE, 0); // disable clock for SPI } /** **************************************************************************************** * @brief Write to 3-wire SPI * @param[in] registerIndex: Target address (A6..A0) * @param[in] valueToWrite: Value to write * * @return Number of read bytes **************************************************************************************** */ void write_to_3wire_SPI_register(uint8_t registerIndex, uint8_t valueToWrite) { GPIO_SetInactive(cs.port, cs.pin); // pull CS low GPIO_SetPinFunction( sdio.port, sdio.pin, OUTPUT, PID_SPI_DO); // configure SDIO as output SetWord16(SPI_RX_TX_REG0, (uint16_t)(registerIndex | 0x80) ); // MSB set to HIGH - A6..A0 Address of register to write to do{ } while (GetBits16(SPI_CTRL_REG,SPI_INT_BIT)==0); // polling to wait for spi transmission SetWord16(SPI_CLEAR_INT_REG, 0); //Clear SPI_CTRL_REG[SPI_INT_BIT] interrupt SetWord16(SPI_RX_TX_REG0, (uint16_t)valueToWrite ); // write data do{ } while (GetBits16(SPI_CTRL_REG,SPI_INT_BIT)==0); // polling to wait for spi transmission SetWord16(SPI_CLEAR_INT_REG, 0); // Clear SPI_CTRL_REG[SPI_INT_BIT] interrupt GPIO_SetActive(cs.port, cs.pin); // set CS high } /** **************************************************************************************** * @brief Read from 3-wire SPI * @param[in] registerIndex: Target address (A6..A0) * * @return byte read **************************************************************************************** */ uint8_t read_from_3wire_SPI_register(uint8_t registerIndex, uint8_t is_last_transaction) { static uint8_t i, dataRead; GPIO_SetInactive(cs.port, cs.pin); // pull CS low GPIO_SetPinFunction( sdio.port, sdio.pin, OUTPUT, PID_SPI_DO); // configure SDIO as output SetWord16(SPI_RX_TX_REG0, (uint16_t)(registerIndex) ); // MSB set to HIGH - A6..A0 Address of register to write to do{ } while (GetBits16(SPI_CTRL_REG,SPI_INT_BIT)==0); // polling to wait for spi transmission SetWord16(SPI_CLEAR_INT_REG, 0); //Clear SPI_CTRL_REG[SPI_INT_BIT] interrupt GPIO_SetPinFunction( sdio.port, sdio.pin, INPUT, PID_SPI_DI); // configure SDIO as input for (i=0; i Tsrad = 4us <-- suitable counter is 6} SetWord16(SPI_RX_TX_REG0, (uint16_t)0x00 ); // dummy write data - read data do{ } while (GetBits16(SPI_CTRL_REG,SPI_INT_BIT)==0); // polling to wait for spi transmission SetWord16(SPI_CLEAR_INT_REG, 0); //Clear SPI_CTRL_REG[SPI_INT_BIT] interrupt dataRead = GetWord16(SPI_RX_TX_REG0); // read received byte SetWord16(SPI_CLEAR_INT_REG, 0x01); // clear pending flag if(is_last_transaction) GPIO_SetActive(cs.port, cs.pin); // set CS high return dataRead; } void burst_write_to_3wire_SPI_register(uint8_t registerIndex) { GPIO_SetPinFunction( sdio.port, sdio.pin, OUTPUT, PID_SPI_DO); // configure SDIO as output SetWord16(SPI_RX_TX_REG0, (uint16_t)(registerIndex) ); // MSB set to HIGH - A6..A0 Address of register to write to do{ } while (GetBits16(SPI_CTRL_REG,SPI_INT_BIT)==0); // polling to wait for spi transmission SetWord16(SPI_CLEAR_INT_REG, 0); // Clear SPI_CTRL_REG[SPI_INT_BIT] interrupt GPIO_SetPinFunction( sdio.port, sdio.pin, INPUT, PID_SPI_DI); // configure SDIO as input } uint8_t burst_read_from_3wire_SPI_register(void) { static uint8_t dataRead; SetWord16(SPI_RX_TX_REG0, (uint16_t)0x00 ); // dummy write data - read data do{ } while (GetBits16(SPI_CTRL_REG,SPI_INT_BIT)==0); // polling to wait for spi transmission SetWord16(SPI_CLEAR_INT_REG, 0); // Clear SPI_CTRL_REG[SPI_INT_BIT] interrupt dataRead = GetWord16(SPI_RX_TX_REG0); // read received byte SetWord16(SPI_CLEAR_INT_REG, 0x01); // clear pending flag return dataRead; } void spi3wire_cs_high (void) { GPIO_SetActive(cs.port, cs.pin); // set CS high } void spi3wire_cs_low (void) { GPIO_SetInactive(cs.port, cs.pin); // set CS low }