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Dependents: WizFi250_AP_HelloWorld
Fork of mbed-src by
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
-
