mbed w/ spi bug fig
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Diff: vendor/Freescale/KL25Z/hal/i2c_api.c
- Revision:
- 13:0645d8841f51
- Parent:
- 12:5fa2273de5db
- Child:
- 14:096882eb0961
--- a/vendor/Freescale/KL25Z/hal/i2c_api.c Wed Jul 24 11:11:21 2013 +0100 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,406 +0,0 @@ -/* mbed Microcontroller Library - * Copyright (c) 2006-2013 ARM Limited - * - * Licensed under the Apache License, Version 2.0 (the "License"); - * you may not use this file except in compliance with the License. - * You may obtain a copy of the License at - * - * http://www.apache.org/licenses/LICENSE-2.0 - * - * Unless required by applicable law or agreed to in writing, software - * distributed under the License is distributed on an "AS IS" BASIS, - * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. - * See the License for the specific language governing permissions and - * limitations under the License. - */ -#include "i2c_api.h" - -#include "cmsis.h" -#include "pinmap.h" -#include "error.h" - -static const PinMap PinMap_I2C_SDA[] = { - {PTE25, I2C_0, 5}, - {PTC9, I2C_0, 2}, - {PTE0, I2C_1, 6}, - {PTB1, I2C_0, 2}, - {PTB3, I2C_0, 2}, - {NC , NC , 0} -}; - -static const PinMap PinMap_I2C_SCL[] = { - {PTE24, I2C_0, 5}, - {PTC8, I2C_0, 2}, - {PTE1, I2C_1, 6}, - {PTB0, I2C_0, 2}, - {PTB2, I2C_0, 2}, - {NC , NC, 0} -}; - -static const uint16_t ICR[0x40] = { - 20, 22, 24, 26, 28, - 30, 34, 40, 28, 32, - 36, 40, 44, 48, 56, - 68, 48, 56, 64, 72, - 80, 88, 104, 128, 80, - 96, 112, 128, 144, 160, - 192, 240, 160, 192, 224, - 256, 288, 320, 384, 480, - 320, 384, 448, 512, 576, - 640, 768, 960, 640, 768, - 896, 1024, 1152, 1280, 1536, - 1920, 1280, 1536, 1792, 2048, - 2304, 2560, 3072, 3840 -}; - -static uint8_t first_read; - - -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); - obj->i2c = (I2C_Type*)pinmap_merge(i2c_sda, i2c_scl); - if ((int)obj->i2c == NC) { - error("I2C pin mapping failed"); - } - - // enable power - switch ((int)obj->i2c) { - case I2C_0: SIM->SCGC5 |= 1 << 13; SIM->SCGC4 |= 1 << 6; break; - case I2C_1: SIM->SCGC5 |= 1 << 11; SIM->SCGC4 |= 1 << 7; break; - } - - // set default frequency at 100k - i2c_frequency(obj, 100000); - - // enable I2C interface - obj->i2c->C1 |= 0x80; - - pinmap_pinout(sda, PinMap_I2C_SDA); - pinmap_pinout(scl, PinMap_I2C_SCL); - - first_read = 1; -} - -int i2c_start(i2c_t *obj) { - // if we are in the middle of a transaction - // activate the repeat_start flag - if (obj->i2c->S & I2C_S_BUSY_MASK) { - obj->i2c->C1 |= 0x04; - } else { - obj->i2c->C1 |= I2C_C1_MST_MASK; - obj->i2c->C1 |= I2C_C1_TX_MASK; - } - first_read = 1; - return 0; -} - -void i2c_stop(i2c_t *obj) { - volatile uint32_t n = 0; - obj->i2c->C1 &= ~I2C_C1_MST_MASK; - obj->i2c->C1 &= ~I2C_C1_TX_MASK; - - // It seems that there are timing problems - // when there is no waiting time after a STOP. - // This wait is also included on the samples - // code provided with the freedom board - for (n = 0; n < 100; n++) __NOP(); - first_read = 1; -} - -static int timeout_status_poll(i2c_t *obj, uint32_t mask) { - uint32_t i, timeout = 1000; - - for (i = 0; i < timeout; i++) { - if (obj->i2c->S & mask) - return 0; - } - - return 1; -} - -// this function waits the end of a tx transfer and return the status of the transaction: -// 0: OK ack received -// 1: OK ack not received -// 2: failure -static int i2c_wait_end_tx_transfer(i2c_t *obj) { - - // wait for the interrupt flag - if (timeout_status_poll(obj, I2C_S_IICIF_MASK)) { - return 2; - } - - obj->i2c->S |= I2C_S_IICIF_MASK; - - // wait transfer complete - if (timeout_status_poll(obj, I2C_S_TCF_MASK)) { - return 2; - } - - // check if we received the ACK or not - return obj->i2c->S & I2C_S_RXAK_MASK ? 1 : 0; -} - -// this function waits the end of a rx transfer and return the status of the transaction: -// 0: OK -// 1: failure -static int i2c_wait_end_rx_transfer(i2c_t *obj) { - // wait for the end of the rx transfer - if (timeout_status_poll(obj, I2C_S_IICIF_MASK)) { - return 1; - } - - obj->i2c->S |= I2C_S_IICIF_MASK; - - return 0; -} - -static void i2c_send_nack(i2c_t *obj) { - obj->i2c->C1 |= I2C_C1_TXAK_MASK; // NACK -} - -static void i2c_send_ack(i2c_t *obj) { - obj->i2c->C1 &= ~I2C_C1_TXAK_MASK; // ACK -} - -static int i2c_do_write(i2c_t *obj, int value) { - // write the data - obj->i2c->D = value; - - // init and wait the end of the transfer - return i2c_wait_end_tx_transfer(obj); -} - -static int i2c_do_read(i2c_t *obj, char * data, int last) { - if (last) - i2c_send_nack(obj); - else - i2c_send_ack(obj); - - *data = (obj->i2c->D & 0xFF); - - // start rx transfer and wait the end of the transfer - return i2c_wait_end_rx_transfer(obj); -} - -void i2c_frequency(i2c_t *obj, int hz) { - uint8_t icr = 0; - uint8_t mult = 0; - uint32_t error = 0; - uint32_t p_error = 0xffffffff; - uint32_t ref = 0; - uint8_t i, j; - // bus clk - uint32_t PCLK = 24000000u; - uint32_t pulse = PCLK / (hz * 2); - - // we look for the values that minimize the error - - // test all the MULT values - for (i = 1; i < 5; i*=2) { - for (j = 0; j < 0x40; j++) { - ref = PCLK / (i*ICR[j]); - error = (ref > hz) ? ref - hz : hz - ref; - if (error < p_error) { - icr = j; - mult = i/2; - p_error = error; - } - } - } - pulse = icr | (mult << 6); - - // I2C Rate - obj->i2c->F = pulse; -} - -int i2c_read(i2c_t *obj, int address, char *data, int length, int stop) { - uint8_t count; - char dummy_read, *ptr; - - if (i2c_start(obj)) { - i2c_stop(obj); - return 1; - } - - if (i2c_do_write(obj, (address | 0x01))) { - i2c_stop(obj); - return 1; - } - - // set rx mode - obj->i2c->C1 &= ~I2C_C1_TX_MASK; - - // Read in bytes - for (count = 0; count < (length); count++) { - ptr = (count == 0) ? &dummy_read : &data[count - 1]; - uint8_t stop_ = (count == (length - 1)) ? 1 : 0; - if (i2c_do_read(obj, ptr, stop_)) { - i2c_stop(obj); - return 1; - } - } - - // If not repeated start, send stop. - if (stop) { - i2c_stop(obj); - } - - // last read - data[count-1] = obj->i2c->D; - - return 0; -} -int i2c_write(i2c_t *obj, int address, const char *data, int length, int stop) { - int i; - - if (i2c_start(obj)) { - i2c_stop(obj); - return 1; - } - - if (i2c_do_write(obj, (address & 0xFE))) { - i2c_stop(obj); - return 1; - } - - for (i = 0; i < length; i++) { - if(i2c_do_write(obj, data[i])) { - i2c_stop(obj); - return 1; - } - } - - if (stop) { - i2c_stop(obj); - } - - return 0; -} - -void i2c_reset(i2c_t *obj) { - i2c_stop(obj); -} - -int i2c_byte_read(i2c_t *obj, int last) { - char data; - - // set rx mode - obj->i2c->C1 &= ~I2C_C1_TX_MASK; - - if(first_read) { - // first dummy read - i2c_do_read(obj, &data, 0); - first_read = 0; - } - - if (last) { - // set tx mode - obj->i2c->C1 |= I2C_C1_TX_MASK; - return obj->i2c->D; - } - - i2c_do_read(obj, &data, last); - - return data; -} - -int i2c_byte_write(i2c_t *obj, int data) { - first_read = 1; - - // set tx mode - obj->i2c->C1 |= I2C_C1_TX_MASK; - - return !i2c_do_write(obj, (data & 0xFF)); -} - - -#if DEVICE_I2CSLAVE -void i2c_slave_mode(i2c_t *obj, int enable_slave) { - if (enable_slave) { - // set slave mode - obj->i2c->C1 &= ~I2C_C1_MST_MASK; - obj->i2c->C1 |= I2C_C1_IICIE_MASK; - } else { - // set master mode - obj->i2c->C1 |= I2C_C1_MST_MASK; - } -} - -int i2c_slave_receive(i2c_t *obj) { - switch(obj->i2c->S) { - // read addressed - case 0xE6: return 1; - - // write addressed - case 0xE2: return 3; - - default: return 0; - } -} - -int i2c_slave_read(i2c_t *obj, char *data, int length) { - uint8_t dummy_read, count; - uint8_t * ptr; - - // set rx mode - obj->i2c->C1 &= ~I2C_C1_TX_MASK; - - // first dummy read - dummy_read = obj->i2c->D; - if(i2c_wait_end_rx_transfer(obj)) { - return 0; - } - - // read address - dummy_read = obj->i2c->D; - if(i2c_wait_end_rx_transfer(obj)) { - return 0; - } - - // read (length - 1) bytes - for (count = 0; count < (length - 1); count++) { - data[count] = obj->i2c->D; - if(i2c_wait_end_rx_transfer(obj)) { - return 0; - } - } - - // read last byte - ptr = (length == 0) ? &dummy_read : (uint8_t *)&data[count]; - *ptr = obj->i2c->D; - - return (length) ? (count + 1) : 0; -} - -int i2c_slave_write(i2c_t *obj, const char *data, int length) { - uint32_t i, count = 0; - - // set tx mode - obj->i2c->C1 |= I2C_C1_TX_MASK; - - for (i = 0; i < length; i++) { - if(i2c_do_write(obj, data[count++]) == 2) { - return 0; - } - } - - // set rx mode - obj->i2c->C1 &= ~I2C_C1_TX_MASK; - - // dummy rx transfer needed - // otherwise the master cannot generate a stop bit - obj->i2c->D; - if(i2c_wait_end_rx_transfer(obj) == 2) { - return 0; - } - - return count; -} - -void i2c_slave_address(i2c_t *obj, int idx, uint32_t address, uint32_t mask) { - obj->i2c->A1 = address & 0xfe; -} -#endif -