tool/mbed/mbed-sdk/libraries/mbed/targets/hal/TARGET_Freescale/TARGET_KPSDK_MCUS/i2c_api.c

   1 /* mbed Microcontroller Library
   2  * Copyright (c) 2006-2013 ARM Limited
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  *     http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16 #include "mbed_assert.h"
  17 #include "i2c_api.h"
  18
  19 #if DEVICE_I2C
  20
  21 #include "cmsis.h"
  22 #include "pinmap.h"
  23 #include "fsl_clock_manager.h"
  24 #include "fsl_i2c_hal.h"
  25 #include "fsl_port_hal.h"
  26 #include "fsl_sim_hal.h"
  27 #include "PeripheralPins.h"
  28
  29 void i2c_init(i2c_t *obj, PinName sda, PinName scl) {
  30     uint32_t i2c_sda = pinmap_peripheral(sda, PinMap_I2C_SDA);
  31     uint32_t i2c_scl = pinmap_peripheral(scl, PinMap_I2C_SCL);
  32     obj->instance = pinmap_merge(i2c_sda, i2c_scl);
  33     MBED_ASSERT((int)obj->instance != NC);
  34
  35     CLOCK_SYS_EnableI2cClock(obj->instance);
  36     uint32_t i2c_addrs[] = I2C_BASE_ADDRS;
  37     I2C_HAL_Init(i2c_addrs[obj->instance]);
  38     I2C_HAL_Enable(i2c_addrs[obj->instance]);
  39     I2C_HAL_SetIntCmd(i2c_addrs[obj->instance], true);
  40     i2c_frequency(obj, 100000);
  41
  42     pinmap_pinout(sda, PinMap_I2C_SDA);
  43     pinmap_pinout(scl, PinMap_I2C_SCL);
  44
  45     uint32_t port_addrs[] = PORT_BASE_ADDRS;
  46     PORT_HAL_SetOpenDrainCmd(port_addrs[sda >> GPIO_PORT_SHIFT], sda & 0xFF, true);
  47     PORT_HAL_SetOpenDrainCmd(port_addrs[scl >> GPIO_PORT_SHIFT], scl & 0xFF, true);
  48 }
  49
  50 int i2c_start(i2c_t *obj) {
  51     uint32_t i2c_addrs[] = I2C_BASE_ADDRS;
  52     I2C_HAL_SendStart(i2c_addrs[obj->instance]);
  53     return 0;
  54 }
  55
  56 int i2c_stop(i2c_t *obj) {
  57     volatile uint32_t n = 0;
  58     uint32_t i2c_addrs[] = I2C_BASE_ADDRS;
  59     if (I2C_HAL_IsMaster(i2c_addrs[obj->instance]))
  60         I2C_HAL_SendStop(i2c_addrs[obj->instance]);
  61
  62     // It seems that there are timing problems
  63     // when there is no waiting time after a STOP.
  64     // This wait is also included on the samples
  65     // code provided with the freedom board
  66     for (n = 0; n < 200; n++) __NOP();
  67     return 0;
  68 }
  69
  70 static int timeout_status_poll(i2c_t *obj, i2c_status_flag_t flag) {
  71     uint32_t i, timeout = 100000;
  72     uint32_t i2c_addrs[] = I2C_BASE_ADDRS;
  73
  74     for (i = 0; i < timeout; i++) {
  75         if (I2C_HAL_GetStatusFlag(i2c_addrs[obj->instance], flag))
  76             return 0;
  77     }
  78     return 1;
  79 }
  80
  81 // this function waits the end of a tx transfer and return the status of the transaction:
  82 //    0: OK ack received
  83 //    1: OK ack not received
  84 //    2: failure
  85 static int i2c_wait_end_tx_transfer(i2c_t *obj) {
  86     // wait for the interrupt flag
  87     uint32_t i2c_addrs[] = I2C_BASE_ADDRS;
  88
  89     if (timeout_status_poll(obj, kI2CInterruptPending)) {
  90         return 2;
  91     }
  92     I2C_HAL_ClearInt(i2c_addrs[obj->instance]);
  93
  94     // wait transfer complete
  95     if (timeout_status_poll(obj, kI2CTransferComplete)) {
  96         return 2;
  97     }
  98
  99     // check if we received the ACK or not
 100     return I2C_HAL_GetStatusFlag(i2c_addrs[obj->instance], kI2CReceivedNak) ? 1 : 0;
 101 }
 102
 103 // this function waits the end of a rx transfer and return the status of the transaction:
 104 //    0: OK
 105 //    1: failure
 106 static int i2c_wait_end_rx_transfer(i2c_t *obj) {
 107     // wait for the end of the rx transfer
 108     if (timeout_status_poll(obj, kI2CInterruptPending)) {
 109         return 1;
 110     }
 111     uint32_t i2c_addrs[] = I2C_BASE_ADDRS;
 112     I2C_HAL_ClearInt(i2c_addrs[obj->instance]);
 113
 114     return 0;
 115 }
 116
 117 static int i2c_do_write(i2c_t *obj, int value) {
 118     uint32_t i2c_addrs[] = I2C_BASE_ADDRS;
 119     I2C_HAL_WriteByte(i2c_addrs[obj->instance], value);
 120
 121     // init and wait the end of the transfer
 122     return i2c_wait_end_tx_transfer(obj);
 123 }
 124
 125 static int i2c_do_read(i2c_t *obj, char * data, int last) {
 126     uint32_t i2c_addrs[] = I2C_BASE_ADDRS;
 127     if (last) {
 128         I2C_HAL_SendNak(i2c_addrs[obj->instance]);
 129     } else {
 130         I2C_HAL_SendAck(i2c_addrs[obj->instance]);
 131     }
 132
 133     *data = (I2C_HAL_ReadByte(i2c_addrs[obj->instance]) & 0xFF);
 134
 135     // start rx transfer and wait the end of the transfer
 136     return i2c_wait_end_rx_transfer(obj);
 137 }
 138
 139 void i2c_frequency(i2c_t *obj, int hz) {
 140     uint32_t busClock;
 141     uint32_t i2c_addrs[] = I2C_BASE_ADDRS;
 142     clock_manager_error_code_t error = CLOCK_SYS_GetFreq(kBusClock, &busClock);
 143     if (error == kClockManagerSuccess) {
 144         I2C_HAL_SetBaudRate(i2c_addrs[obj->instance], busClock, hz / 1000, NULL);
 145     }
 146 }
 147
 148 int i2c_read(i2c_t *obj, int address, char *data, int length, int stop) {
 149     int count;
 150     char dummy_read, *ptr;
 151
 152     if (i2c_start(obj)) {
 153         i2c_stop(obj);
 154         return I2C_ERROR_BUS_BUSY;
 155     }
 156
 157     if (i2c_do_write(obj, (address | 0x01))) {
 158         i2c_stop(obj);
 159         return I2C_ERROR_NO_SLAVE;
 160     }
 161
 162     // set rx mode
 163     uint32_t i2c_addrs[] = I2C_BASE_ADDRS;
 164     I2C_HAL_SetDirMode(i2c_addrs[obj->instance], kI2CReceive);
 165
 166     // Read in bytes
 167     for (count = 0; count < (length); count++) {
 168         ptr = (count == 0) ? &dummy_read : &data[count - 1];
 169         uint8_t stop_ = (count == (length - 1)) ? 1 : 0;
 170         if (i2c_do_read(obj, ptr, stop_)) {
 171             i2c_stop(obj);
 172             return count;
 173         }
 174     }
 175
 176     // If not repeated start, send stop.
 177     if (stop)
 178         i2c_stop(obj);
 179
 180     // last read
 181     data[count-1] = I2C_HAL_ReadByte(i2c_addrs[obj->instance]);
 182
 183     return length;
 184 }
 185
 186 int i2c_write(i2c_t *obj, int address, const char *data, int length, int stop) {
 187     int i;
 188
 189     if (i2c_start(obj)) {
 190         i2c_stop(obj);
 191         return I2C_ERROR_BUS_BUSY;
 192     }
 193
 194     if (i2c_do_write(obj, (address & 0xFE))) {
 195         i2c_stop(obj);
 196         return I2C_ERROR_NO_SLAVE;
 197     }
 198
 199     for (i = 0; i < length; i++) {
 200         if(i2c_do_write(obj, data[i])) {
 201             i2c_stop(obj);
 202             return i;
 203         }
 204     }
 205
 206     if (stop)
 207         i2c_stop(obj);
 208
 209     return length;
 210 }
 211
 212 void i2c_reset(i2c_t *obj) {
 213     i2c_stop(obj);
 214 }
 215
 216 int i2c_byte_read(i2c_t *obj, int last) {
 217     char data;
 218     uint32_t i2c_addrs[] = I2C_BASE_ADDRS;
 219     // set rx mode
 220     I2C_HAL_SetDirMode(i2c_addrs[obj->instance], kI2CReceive);
 221
 222     // Setup read
 223     i2c_do_read(obj, &data, last);
 224
 225     // set tx mode
 226     I2C_HAL_SetDirMode(i2c_addrs[obj->instance], kI2CSend);
 227     return I2C_HAL_ReadByte(i2c_addrs[obj->instance]);
 228 }
 229
 230 int i2c_byte_write(i2c_t *obj, int data) {
 231     uint32_t i2c_addrs[] = I2C_BASE_ADDRS;
 232     // set tx mode
 233     I2C_HAL_SetDirMode(i2c_addrs[obj->instance], kI2CSend);
 234
 235     return !i2c_do_write(obj, (data & 0xFF));
 236 }
 237
 238
 239 #if DEVICE_I2CSLAVE
 240 void i2c_slave_mode(i2c_t *obj, int enable_slave) {
 241     uint32_t i2c_addrs[] = I2C_BASE_ADDRS;
 242     if (enable_slave) {
 243         // set slave mode
 244         BW_I2C_C1_MST(i2c_addrs[obj->instance], 0);
 245         I2C_HAL_SetIntCmd(i2c_addrs[obj->instance], true);
 246     } else {
 247         // set master mode
 248         BW_I2C_C1_MST(i2c_addrs[obj->instance], 1);
 249     }
 250 }
 251
 252 int i2c_slave_receive(i2c_t *obj) {
 253     uint32_t i2c_addrs[] = I2C_BASE_ADDRS;
 254     switch(HW_I2C_S_RD(i2c_addrs[obj->instance])) {
 255         // read addressed
 256         case 0xE6:
 257             return 1;
 258         // write addressed
 259         case 0xE2:
 260             return 3;
 261         default:
 262             return 0;
 263     }
 264 }
 265
 266 int i2c_slave_read(i2c_t *obj, char *data, int length) {
 267     uint8_t dummy_read;
 268     uint8_t *ptr;
 269     int count;
 270     uint32_t i2c_addrs[] = I2C_BASE_ADDRS;
 271     // set rx mode
 272     I2C_HAL_SetDirMode(i2c_addrs[obj->instance], kI2CSend);
 273
 274     // first dummy read
 275     dummy_read = I2C_HAL_ReadByte(i2c_addrs[obj->instance]);
 276     if (i2c_wait_end_rx_transfer(obj))
 277         return 0;
 278
 279     // read address
 280     dummy_read = I2C_HAL_ReadByte(i2c_addrs[obj->instance]);
 281     if (i2c_wait_end_rx_transfer(obj))
 282         return 0;
 283
 284     // read (length - 1) bytes
 285     for (count = 0; count < (length - 1); count++) {
 286         data[count] = I2C_HAL_ReadByte(i2c_addrs[obj->instance]);
 287         if (i2c_wait_end_rx_transfer(obj))
 288             return count;
 289     }
 290
 291     // read last byte
 292     ptr = (length == 0) ? &dummy_read : (uint8_t *)&data[count];
 293     *ptr = I2C_HAL_ReadByte(i2c_addrs[obj->instance]);
 294
 295     return (length) ? (count + 1) : 0;
 296 }
 297
 298 int i2c_slave_write(i2c_t *obj, const char *data, int length) {
 299     int i, count = 0;
 300     uint32_t i2c_addrs[] = I2C_BASE_ADDRS;
 301
 302     // set tx mode
 303     I2C_HAL_SetDirMode(i2c_addrs[obj->instance], kI2CSend);
 304
 305     for (i = 0; i < length; i++) {
 306         if (i2c_do_write(obj, data[count++]) == 2)
 307             return i;
 308     }
 309
 310     // set rx mode
 311     I2C_HAL_SetDirMode(i2c_addrs[obj->instance], kI2CReceive);
 312
 313     // dummy rx transfer needed
 314     // otherwise the master cannot generate a stop bit
 315     I2C_HAL_ReadByte(i2c_addrs[obj->instance]);
 316     if (i2c_wait_end_rx_transfer(obj) == 2)
 317         return count;
 318
 319     return count;
 320 }
 321
 322 void i2c_slave_address(i2c_t *obj, int idx, uint32_t address, uint32_t mask) {
 323     uint32_t i2c_addrs[] = I2C_BASE_ADDRS;
 324     I2C_HAL_SetUpperAddress7bit(i2c_addrs[obj->instance], address & 0xfe);
 325 }
 326 #endif
 327
 328 #endif