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targets/TARGET_Maxim/TARGET_MAX32610/i2c_api.c
- Committer:
- <>
- Date:
- 2016-10-28
- Revision:
- 149:156823d33999
- Parent:
- targets/hal/TARGET_Maxim/TARGET_MAX32610/i2c_api.c@ 144:ef7eb2e8f9f7
File content as of revision 149:156823d33999:
/******************************************************************************* * Copyright (C) 2015 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 "i2c_api.h" #include "cmsis.h" #include "i2cm_regs.h" #include "clkman_regs.h" #include "ioman_regs.h" #include "PeripheralPins.h" #define I2C_SLAVE_ADDR_READ_BIT 0x0001 #ifndef MXC_I2CM_TX_TIMEOUT #define MXC_I2CM_TX_TIMEOUT 0x5000 #endif #ifndef MXC_I2CM_RX_TIMEOUT #define MXC_I2CM_RX_TIMEOUT 0x5000 #endif typedef enum { /** 100KHz */ MXC_E_I2CM_SPEED_100KHZ = 0, /** 400KHz */ MXC_E_I2CM_SPEED_400KHZ, /** 1MHz */ MXC_E_I2CM_SPEED_1MHZ } i2cm_speed_t; /* Clock divider lookup table */ static const uint32_t clk_div_table[3][8] = { /* MXC_E_I2CM_SPEED_100KHZ */ { /* 0: */ 0, /* not supported */ /* 1: 6MHz */ (( 3 << MXC_F_I2CM_CLK_DIV_FILTER_CLK_DIV_POS) | ( 7 << MXC_F_I2CM_CLK_DIV_SCL_HI_CNT_POS) | ( 36 << MXC_F_I2CM_CLK_DIV_SCL_LO_CNT_POS)), /* 2: 8MHz */ (( 4 << MXC_F_I2CM_CLK_DIV_FILTER_CLK_DIV_POS) | (10 << MXC_F_I2CM_CLK_DIV_SCL_HI_CNT_POS) | ( 48 << MXC_F_I2CM_CLK_DIV_SCL_LO_CNT_POS)), /* 3: 12MHz */ (( 6 << MXC_F_I2CM_CLK_DIV_FILTER_CLK_DIV_POS) | (17 << MXC_F_I2CM_CLK_DIV_SCL_HI_CNT_POS) | ( 72 << MXC_F_I2CM_CLK_DIV_SCL_LO_CNT_POS)), /* 4: 16MHz */ (( 8 << MXC_F_I2CM_CLK_DIV_FILTER_CLK_DIV_POS) | (24 << MXC_F_I2CM_CLK_DIV_SCL_HI_CNT_POS) | ( 96 << MXC_F_I2CM_CLK_DIV_SCL_LO_CNT_POS)), /* 5: */ 0, /* not supported */ /* 6: */ 0, /* not supported */ /* 7: 24MHz */ ((12 << MXC_F_I2CM_CLK_DIV_FILTER_CLK_DIV_POS) | (38 << MXC_F_I2CM_CLK_DIV_SCL_HI_CNT_POS) | (144 << MXC_F_I2CM_CLK_DIV_SCL_LO_CNT_POS)), }, /* MXC_E_I2CM_SPEED_400KHZ */ { /* 0: */ 0, /* not supported */ /* 1: */ 0, /* not supported */ /* 2: */ 0, /* not supported */ /* 3: 12MHz */ ((2 << MXC_F_I2CM_CLK_DIV_FILTER_CLK_DIV_POS) | (1 << MXC_F_I2CM_CLK_DIV_SCL_HI_CNT_POS) | (18 << MXC_F_I2CM_CLK_DIV_SCL_LO_CNT_POS)), /* 4: 16MHz */ ((2 << MXC_F_I2CM_CLK_DIV_FILTER_CLK_DIV_POS) | (2 << MXC_F_I2CM_CLK_DIV_SCL_HI_CNT_POS) | (24 << MXC_F_I2CM_CLK_DIV_SCL_LO_CNT_POS)), /* 5: */ 0, /* not supported */ /* 6: */ 0, /* not supported */ /* 7: 24MHz */ ((3 << MXC_F_I2CM_CLK_DIV_FILTER_CLK_DIV_POS) | (5 << MXC_F_I2CM_CLK_DIV_SCL_HI_CNT_POS) | (36 << MXC_F_I2CM_CLK_DIV_SCL_LO_CNT_POS)), }, /* MXC_E_I2CM_SPEED_1MHZ */ { /* 0: */ 0, /* not supported */ /* 1: */ 0, /* not supported */ /* 2: */ 0, /* not supported */ /* 3: */ 0, /* not supported */ /* 4: */ 0, /* not supported */ /* 5: */ 0, /* not supported */ /* 6: */ 0, /* not supported */ /* 7: 24MHz */ ((1 << MXC_F_I2CM_CLK_DIV_FILTER_CLK_DIV_POS) | (0 << MXC_F_I2CM_CLK_DIV_SCL_HI_CNT_POS) | (14 << MXC_F_I2CM_CLK_DIV_SCL_LO_CNT_POS)), }, }; void i2c_init(i2c_t *obj, PinName sda, PinName scl) { // determine the I2C to use I2CName i2c_sda = (I2CName)pinmap_peripheral(sda, PinMap_I2C_SDA); I2CName i2c_scl = (I2CName)pinmap_peripheral(scl, PinMap_I2C_SCL); mxc_i2cm_regs_t *i2c = (mxc_i2cm_regs_t*)pinmap_merge(i2c_sda, i2c_scl); MBED_ASSERT((int)i2c != NC); obj->i2c = i2c; obj->txfifo = (uint16_t*)MXC_I2CM_GET_BASE_TX_FIFO(MXC_I2CM_BASE_TO_INSTANCE(i2c)); obj->rxfifo = (uint16_t*)MXC_I2CM_GET_BASE_RX_FIFO(MXC_I2CM_BASE_TO_INSTANCE(i2c)); obj->start_pending = 0; obj->stop_pending = 0; // configure the pins pinmap_pinout(sda, PinMap_I2C_SDA); pinmap_pinout(scl, PinMap_I2C_SCL); // enable the clock MXC_CLKMAN->clk_ctrl_6_i2cm = MXC_E_CLKMAN_CLK_SCALE_ENABLED; // reset module i2c->ctrl = MXC_F_I2CM_CTRL_MSTR_RESET_EN; i2c->ctrl = 0; // set default frequency at 100k i2c_frequency(obj, 100000); // set timeout to 255 ms and turn on the auto-stop option i2c->timeout = (0xFF << MXC_F_I2CM_TIMEOUT_TX_TIMEOUT_POS) | MXC_F_I2CM_TIMEOUT_AUTO_STOP_EN; // enable tx_fifo and rx_fifo i2c->ctrl |= (MXC_F_I2CM_CTRL_TX_FIFO_EN | MXC_F_I2CM_CTRL_RX_FIFO_EN); } void i2c_frequency(i2c_t *obj, int hz) { // compute clock array index int clki = ((SystemCoreClock + 1500000) / 3000000) - 1; // get clock divider settings from lookup table if ((hz < 400000) && (clk_div_table[MXC_E_I2CM_SPEED_100KHZ][clki] > 0)) { obj->i2c->fs_clk_div = clk_div_table[MXC_E_I2CM_SPEED_100KHZ][clki]; } else if ((hz < 1000000) && (clk_div_table[MXC_E_I2CM_SPEED_400KHZ][clki] > 0)) { obj->i2c->fs_clk_div = clk_div_table[MXC_E_I2CM_SPEED_400KHZ][clki]; } else if ((hz >= 1000000) && (clk_div_table[MXC_E_I2CM_SPEED_1MHZ][clki] > 0)) { obj->i2c->hs_clk_div = clk_div_table[MXC_E_I2CM_SPEED_1MHZ][clki]; } } static int write_tx_fifo(i2c_t *obj, const uint16_t data) { int timeout = MXC_I2CM_TX_TIMEOUT; while (*obj->txfifo) { uint32_t intfl = obj->i2c->intfl; if (intfl & MXC_F_I2CM_INTFL_TX_NACKED) { return I2C_ERROR_NO_SLAVE; } if (!timeout || (intfl & (MXC_F_I2CM_INTFL_TX_TIMEOUT | MXC_F_I2CM_INTFL_TX_LOST_ARBITR))) { return I2C_ERROR_BUS_BUSY; } timeout--; } *obj->txfifo = data; return 0; } static int wait_tx_in_progress(i2c_t *obj) { int timeout = MXC_I2CM_TX_TIMEOUT; while ((obj->i2c->trans & MXC_F_I2CM_TRANS_TX_IN_PROGRESS) && --timeout); uint32_t intfl = obj->i2c->intfl; if (intfl & MXC_F_I2CM_INTFL_TX_NACKED) { i2c_reset(obj); return I2C_ERROR_NO_SLAVE; } if (!timeout || (intfl & (MXC_F_I2CM_INTFL_TX_TIMEOUT | MXC_F_I2CM_INTFL_TX_LOST_ARBITR))) { i2c_reset(obj); return I2C_ERROR_BUS_BUSY; } return 0; } int i2c_start(i2c_t *obj) { obj->start_pending = 1; return 0; } int i2c_stop(i2c_t *obj) { obj->start_pending = 0; write_tx_fifo(obj, MXC_S_I2CM_TRANS_TAG_STOP); return wait_tx_in_progress(obj); } void i2c_reset(i2c_t *obj) { obj->i2c->ctrl = MXC_F_I2CM_CTRL_MSTR_RESET_EN; obj->i2c->intfl = 0x3FF; // clear all interrupts obj->i2c->ctrl = MXC_F_I2CM_CTRL_TX_FIFO_EN | MXC_F_I2CM_CTRL_RX_FIFO_EN; obj->start_pending = 0; } int i2c_byte_write(i2c_t *obj, int data) { int err; // clear all interrupts obj->i2c->intfl = 0x3FF; if (obj->start_pending) { obj->start_pending = 0; data = (data & 0xFF) | MXC_S_I2CM_TRANS_TAG_START; } else { data = (data & 0xFF) | MXC_S_I2CM_TRANS_TAG_TXDATA_ACK; } if ((err = write_tx_fifo(obj, data)) != 0) { return err; } obj->i2c->trans |= MXC_F_I2CM_TRANS_TX_START; // Wait for the FIFO to be empty while (!(obj->i2c->intfl & MXC_F_I2CM_INTFL_TX_FIFO_EMPTY)); if (obj->i2c->intfl & MXC_F_I2CM_INTFL_TX_NACKED) { i2c_reset(obj); return 0; } if (obj->i2c->intfl & (MXC_F_I2CM_INTFL_TX_TIMEOUT | MXC_F_I2CM_INTFL_TX_LOST_ARBITR)) { i2c_reset(obj); return 2; } return 1; } int i2c_byte_read(i2c_t *obj, int last) { uint16_t fifo_value; int err; // clear all interrupts obj->i2c->intfl = 0x3FF; if (last) { fifo_value = MXC_S_I2CM_TRANS_TAG_RXDATA_NACK; } else { fifo_value = MXC_S_I2CM_TRANS_TAG_RXDATA_COUNT; } if ((err = write_tx_fifo(obj, fifo_value)) != 0) { i2c_reset(obj); return err; } obj->i2c->trans |= MXC_F_I2CM_TRANS_TX_START; int timeout = MXC_I2CM_RX_TIMEOUT; while (!(obj->i2c->intfl & MXC_F_I2CM_INTFL_RX_FIFO_NOT_EMPTY) && (!(obj->i2c->bb & MXC_F_I2CM_BB_RX_FIFO_CNT))) { if ((--timeout < 0) || (obj->i2c->trans & (MXC_F_I2CM_TRANS_TX_TIMEOUT | MXC_F_I2CM_TRANS_TX_LOST_ARBITR | MXC_F_I2CM_TRANS_TX_NACKED))) { break; } } if (obj->i2c->intfl & MXC_F_I2CM_INTFL_RX_FIFO_NOT_EMPTY) { obj->i2c->intfl = MXC_F_I2CM_INTFL_RX_FIFO_NOT_EMPTY; return *obj->rxfifo; } i2c_reset(obj); return -1; } int i2c_write(i2c_t *obj, int address, const char *data, int length, int stop) { int err, retval = 0; int i; if (!(obj->stop_pending) && (obj->i2c->trans & MXC_F_I2CM_TRANS_TX_IN_PROGRESS)) { return 0; } // clear all interrupts obj->i2c->intfl = 0x3FF; // write the address to the fifo if ((err = write_tx_fifo(obj, (MXC_S_I2CM_TRANS_TAG_START | address))) != 0) { // start + addr (write) i2c_reset(obj); return err; } obj->start_pending = 0; // start the transaction obj->i2c->trans |= MXC_F_I2CM_TRANS_TX_START; // load as much of the cmd into the FIFO as possible for (i = 0; i < length; i++) { if ((err = write_tx_fifo(obj, (MXC_S_I2CM_TRANS_TAG_TXDATA_ACK | data[i]))) != 0) { // cmd (expect ACK) retval = (retval ? retval : err); break; } } if (stop) { obj->stop_pending = 0; if ((err = write_tx_fifo(obj, MXC_S_I2CM_TRANS_TAG_STOP)) != 0) { // stop condition retval = (retval ? retval : err); } if ((err = wait_tx_in_progress(obj)) != 0) { retval = (retval ? retval : err); } } else { obj->stop_pending = 1; int timeout = MXC_I2CM_TX_TIMEOUT; // Wait for TX fifo to be empty while (!(obj->i2c->intfl & MXC_F_I2CM_INTFL_TX_FIFO_EMPTY) && timeout--); } if (retval == 0) { return length; } i2c_reset(obj); return retval; } int i2c_read(i2c_t *obj, int address, char *data, int length, int stop) { int err, retval = 0; int i = length; int timeout; if (!(obj->stop_pending) && (obj->i2c->trans & MXC_F_I2CM_TRANS_TX_IN_PROGRESS)) { return 0; } // clear all interrupts obj->i2c->intfl = 0x3FF; // start + addr (read) if ((retval = write_tx_fifo(obj, (MXC_S_I2CM_TRANS_TAG_START | address | I2C_SLAVE_ADDR_READ_BIT))) != 0) { goto read_done; } obj->start_pending = 0; while (i > 256) { if ((retval = write_tx_fifo(obj, (MXC_S_I2CM_TRANS_TAG_RXDATA_COUNT | 255))) != 0) { goto read_done; } i -= 256; } if (i > 1) { if ((retval = write_tx_fifo(obj, (MXC_S_I2CM_TRANS_TAG_RXDATA_COUNT | (i - 2)))) != 0) { goto read_done; } } // start the transaction obj->i2c->trans |= MXC_F_I2CM_TRANS_TX_START; if ((retval = write_tx_fifo(obj, MXC_S_I2CM_TRANS_TAG_RXDATA_NACK)) != 0) { // NACK last data byte goto read_done; } if (stop) { if ((retval = write_tx_fifo(obj, MXC_S_I2CM_TRANS_TAG_STOP)) != 0) { // stop condition goto read_done; } } timeout = MXC_I2CM_RX_TIMEOUT; i = 0; while (i < length) { while (!(obj->i2c->intfl & MXC_F_I2CM_INTFL_RX_FIFO_NOT_EMPTY) && (!(obj->i2c->bb & MXC_F_I2CM_BB_RX_FIFO_CNT))) { if ((--timeout < 0) || (obj->i2c->trans & (MXC_F_I2CM_TRANS_TX_TIMEOUT | MXC_F_I2CM_TRANS_TX_LOST_ARBITR | MXC_F_I2CM_TRANS_TX_NACKED))) { retval = -3; goto read_done; } } timeout = MXC_I2CM_RX_TIMEOUT; obj->i2c->intfl = MXC_F_I2CM_INTFL_RX_FIFO_NOT_EMPTY; uint16_t temp = *obj->rxfifo; if (temp & MXC_S_I2CM_RSTLS_TAG_EMPTY) { continue; } data[i++] = (uint8_t) temp; } read_done: if (stop) { obj->stop_pending = 0; if ((err = wait_tx_in_progress(obj)) != 0) { retval = (retval ? retval : err); } } else { obj->stop_pending = 1; } if (retval == 0) { return length; } i2c_reset(obj); return retval; }