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Diff: targets/TARGET_Maxim/TARGET_MAX32630/spi_api.c
- Revision:
- 157:ff67d9f36b67
- Child:
- 167:e84263d55307
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/targets/TARGET_Maxim/TARGET_MAX32630/spi_api.c Thu Feb 02 17:01:33 2017 +0000 @@ -0,0 +1,181 @@ +/******************************************************************************* + * Copyright (c) 2016 Maxim Integrated Products, Inc., All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included + * in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. + * IN NO EVENT SHALL MAXIM INTEGRATED BE LIABLE FOR ANY CLAIM, DAMAGES + * OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, + * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR + * OTHER DEALINGS IN THE SOFTWARE. + * + * Except as contained in this notice, the name of Maxim Integrated + * Products, Inc. shall not be used except as stated in the Maxim Integrated + * Products, Inc. Branding Policy. + * + * The mere transfer of this software does not imply any licenses + * of trade secrets, proprietary technology, copyrights, patents, + * trademarks, maskwork rights, or any other form of intellectual + * property whatsoever. Maxim Integrated Products, Inc. retains all + * ownership rights. + ******************************************************************************* + */ + +#include "mbed_assert.h" +#include "spi_api.h" // mbed HAL +#include "spim_regs.h" // bare metal +#include "spim.h" // Maxim CMSIS driver +#include "pinmap.h" +#include "PeripheralPins.h" + +//****************************************************************************** +void spi_init(spi_t *obj, PinName mosi, PinName miso, PinName sclk, PinName ssel) +{ + // Make sure pins are pointing to the same SPI instance + SPIName spi_mosi = (SPIName)pinmap_peripheral(mosi, PinMap_SPI_MOSI); + SPIName spi_miso = (SPIName)pinmap_peripheral(miso, PinMap_SPI_MISO); + SPIName spi_sclk = (SPIName)pinmap_peripheral(sclk, PinMap_SPI_SCLK); + SPIName spi_ssel = (SPIName)pinmap_peripheral(ssel, PinMap_SPI_SSEL); + + SPIName spi_data = (SPIName)pinmap_merge(spi_mosi, spi_miso); + SPIName spi_cntl; + + // Control is SCK and optionaly SS + if ((SPIName)spi_ssel != (SPIName)NC) { + spi_cntl = (SPIName)pinmap_merge(spi_sclk, spi_ssel); + } else { + spi_cntl = spi_sclk; + } + + SPIName spi = (SPIName)pinmap_merge(spi_data, spi_cntl); + + MBED_ASSERT((SPIName)spi != (SPIName)NC); + + obj->spi = (mxc_spim_regs_t *)spi; + + // Merge pin function requests for use with CMSIS init func + ioman_req_t io_req; + pin_function_t *pin_func; + pin_func = (pin_function_t *)pinmap_find_function(mosi, PinMap_SPI_MOSI); + io_req.value = pin_func->req_val; + pin_func = (pin_function_t *)pinmap_find_function(miso, PinMap_SPI_MISO); + io_req.value |= pin_func->req_val; + pin_func = (pin_function_t *)pinmap_find_function(sclk, PinMap_SPI_SCLK); + io_req.value |= pin_func->req_val; + if ((SPIName)spi_ssel != (SPIName)NC) { + pin_func = (pin_function_t *)pinmap_find_function(ssel, PinMap_SPI_SSEL); + io_req.value |= pin_func->req_val; + } + + // Using req and ack pointers of last pin function lookup + sys_cfg_spim_t sys_cfg; + sys_cfg.io_cfg.req_reg = pin_func->reg_req; + sys_cfg.io_cfg.ack_reg = pin_func->reg_ack; + sys_cfg.io_cfg.req_val = io_req; + sys_cfg.clk_scale = CLKMAN_SCALE_AUTO; + + // Defaults + spim_cfg_t spim_cfg; + spim_cfg.mode = 0; + spim_cfg.ssel_pol = 0; + spim_cfg.baud = 1000000; + + SPIM_Init(obj->spi, &spim_cfg, &sys_cfg); + + obj->index = MXC_SPIM_GET_IDX(obj->spi); +} + +//****************************************************************************** +void spi_format(spi_t *obj, int bits, int mode, int slave) +{ + // Check the validity of the inputs + MBED_ASSERT(bits == 8); + + // Only supports master mode + MBED_ASSERT(!slave); + + // Set the mode + obj->spi->mstr_cfg &= ~(MXC_F_SPIM_MSTR_CFG_SPI_MODE); + obj->spi->mstr_cfg |= (mode << MXC_F_SPIM_MSTR_CFG_SPI_MODE_POS); +} + +//****************************************************************************** +void spi_frequency(spi_t *obj, int hz) +{ + // Maximum frequency is half the system frequency + MBED_ASSERT((unsigned int)hz <= (SystemCoreClock / 2)); + unsigned clocks = ((SystemCoreClock / 2) / hz); + + // Figure out the divider ratio + int clk_div = 1; + while(clk_div < 10) { + if(clocks < 0x10) { + break; + } + clk_div++; + clocks = clocks >> 1; + } + + // Turn on the SPI clock + if(obj->index == 0) { + MXC_CLKMAN->sys_clk_ctrl_11_spi0 = clk_div; + } else if(obj->index == 1) { + MXC_CLKMAN->sys_clk_ctrl_12_spi1 = clk_div; + } else if(obj->index == 2) { + MXC_CLKMAN->sys_clk_ctrl_13_spi2 = clk_div; + } else { + MBED_ASSERT(0); + } + + // Set the number of clocks to hold sclk high and low + MXC_SET_FIELD(&obj->spi->mstr_cfg, + (MXC_F_SPIM_MSTR_CFG_SCK_HI_CLK | MXC_F_SPIM_MSTR_CFG_SCK_LO_CLK), + ((clocks << MXC_F_SPIM_MSTR_CFG_SCK_HI_CLK_POS) | (clocks << MXC_F_SPIM_MSTR_CFG_SCK_LO_CLK_POS))); +} + +//****************************************************************************** +int spi_master_write(spi_t *obj, int value) +{ + spim_req_t req; + uint8_t out; + uint8_t in; + + out = value; + + req.ssel = 0; + req.deass = 0; + req.tx_data = &out; + req.rx_data = ∈ + req.width = SPIM_WIDTH_1; + req.len = 1; + req.ssel = 0; + req.deass = 1; + req.callback = NULL; + + SPIM_Trans(obj->spi, &req); + + return *req.rx_data; +} + +//****************************************************************************** +int spi_busy(spi_t *obj) +{ + return SPIM_Busy(obj->spi); +} + +//****************************************************************************** +uint8_t spi_get_module(spi_t *obj) +{ + return obj->index; +} +