t
Fork of mbed-dev by
targets/TARGET_Maxim/TARGET_MAX32630/spi_api.c
- Committer:
- AnnaBridge
- Date:
- 2017-06-21
- Revision:
- 167:e84263d55307
- Parent:
- 157:ff67d9f36b67
- Child:
- 170:19eb464bc2be
File content as of revision 167:e84263d55307:
/******************************************************************************* * 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_master_block_write(spi_t *obj, const char *tx_buffer, int tx_length, char *rx_buffer, int rx_length) { int total = (tx_length > rx_length) ? tx_length : rx_length; for (int i = 0; i < total; i++) { char out = (i < tx_length) ? tx_buffer[i] : 0xff; char in = spi_master_write(obj, out); if (i < rx_length) { rx_buffer[i] = in; } } return total; } //****************************************************************************** int spi_busy(spi_t *obj) { return SPIM_Busy(obj->spi); } //****************************************************************************** uint8_t spi_get_module(spi_t *obj) { return obj->index; }