tmk_core/tool/mbed/mbed-sdk/libraries/mbed/targets/hal/TARGET_STM/TARGET_STM32L1/i2c_api.c

   1 /* mbed Microcontroller Library
   2  *******************************************************************************
   3  * Copyright (c) 2014, STMicroelectronics
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions are met:
   8  *
   9  * 1. Redistributions of source code must retain the above copyright notice,
  10  *    this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright notice,
  12  *    this list of conditions and the following disclaimer in the documentation
  13  *    and/or other materials provided with the distribution.
  14  * 3. Neither the name of STMicroelectronics nor the names of its contributors
  15  *    may be used to endorse or promote products derived from this software
  16  *    without specific prior written permission.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  19  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  21  * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
  22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  24  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  25  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  26  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  27  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  28  *******************************************************************************
  29  */
  30 #include "mbed_assert.h"
  31 #include "i2c_api.h"
  32
  33 #if DEVICE_I2C
  34
  35 #include "cmsis.h"
  36 #include "pinmap.h"
  37 #include "PeripheralPins.h"
  38
  39 /* Timeout values for flags and events waiting loops. These timeouts are
  40    not based on accurate values, they just guarantee that the application will
  41    not remain stuck if the I2C communication is corrupted. */
  42 #define FLAG_TIMEOUT ((int)0x1000)
  43 #define LONG_TIMEOUT ((int)0x8000)
  44
  45 I2C_HandleTypeDef I2cHandle;
  46
  47 int i2c1_inited = 0;
  48 int i2c2_inited = 0;
  49
  50 void i2c_init(i2c_t *obj, PinName sda, PinName scl)
  51 {
  52     // Determine the I2C to use
  53     I2CName i2c_sda = (I2CName)pinmap_peripheral(sda, PinMap_I2C_SDA);
  54     I2CName i2c_scl = (I2CName)pinmap_peripheral(scl, PinMap_I2C_SCL);
  55
  56     obj->i2c = (I2CName)pinmap_merge(i2c_sda, i2c_scl);
  57     MBED_ASSERT(obj->i2c != (I2CName)NC);
  58
  59     // Enable I2C1 clock and pinout if not done
  60     if ((obj->i2c == I2C_1) && !i2c1_inited) {
  61         i2c1_inited = 1;
  62         __I2C1_CLK_ENABLE();
  63         // Configure I2C pins
  64         pinmap_pinout(sda, PinMap_I2C_SDA);
  65         pinmap_pinout(scl, PinMap_I2C_SCL);
  66         pin_mode(sda, OpenDrain);
  67         pin_mode(scl, OpenDrain);
  68     }
  69     // Enable I2C2 clock and pinout if not done
  70     if ((obj->i2c == I2C_2) && !i2c2_inited) {
  71         i2c2_inited = 1;
  72         __I2C2_CLK_ENABLE();
  73         // Configure I2C pins
  74         pinmap_pinout(sda, PinMap_I2C_SDA);
  75         pinmap_pinout(scl, PinMap_I2C_SCL);
  76         pin_mode(sda, OpenDrain);
  77         pin_mode(scl, OpenDrain);
  78     }
  79
  80     // Reset to clear pending flags if any
  81     i2c_reset(obj);
  82
  83     // I2C configuration
  84     i2c_frequency(obj, 100000); // 100 kHz per default
  85
  86     // I2C master by default
  87     obj->slave = 0;
  88 }
  89
  90 void i2c_frequency(i2c_t *obj, int hz)
  91 {
  92     MBED_ASSERT((hz != 0) && (hz <= 400000));
  93     I2cHandle.Instance = (I2C_TypeDef *)(obj->i2c);
  94     int timeout;
  95
  96     // wait before init
  97     timeout = LONG_TIMEOUT;
  98     while ((__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_BUSY)) && (timeout-- != 0));
  99
 100     // I2C configuration
 101     I2cHandle.Init.AddressingMode  = I2C_ADDRESSINGMODE_7BIT;
 102     I2cHandle.Init.ClockSpeed      = hz;
 103     I2cHandle.Init.DualAddressMode = I2C_DUALADDRESS_DISABLED;
 104     I2cHandle.Init.DutyCycle       = I2C_DUTYCYCLE_2;
 105     I2cHandle.Init.GeneralCallMode = I2C_GENERALCALL_DISABLED;
 106     I2cHandle.Init.NoStretchMode   = I2C_NOSTRETCH_DISABLED;
 107     I2cHandle.Init.OwnAddress1     = 0;
 108     I2cHandle.Init.OwnAddress2     = 0;
 109     HAL_I2C_Init(&I2cHandle);
 110     if (obj->slave) {
 111         /* Enable Address Acknowledge */
 112         I2cHandle.Instance->CR1 |= I2C_CR1_ACK;
 113     }
 114
 115 }
 116
 117 inline int i2c_start(i2c_t *obj)
 118 {
 119     I2C_TypeDef *i2c = (I2C_TypeDef *)(obj->i2c);
 120     int timeout;
 121
 122     I2cHandle.Instance = (I2C_TypeDef *)(obj->i2c);
 123
 124     // Clear Acknowledge failure flag
 125     __HAL_I2C_CLEAR_FLAG(&I2cHandle, I2C_FLAG_AF);
 126
 127     // Generate the START condition
 128     i2c->CR1 |= I2C_CR1_START;
 129
 130     // Wait the START condition has been correctly sent
 131     timeout = FLAG_TIMEOUT;
 132     while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_SB) == RESET) {
 133         if ((timeout--) == 0) {
 134             return 1;
 135         }
 136     }
 137
 138     return 0;
 139 }
 140
 141 inline int i2c_stop(i2c_t *obj)
 142 {
 143     I2C_TypeDef *i2c = (I2C_TypeDef *)(obj->i2c);
 144
 145     // Generate the STOP condition
 146     i2c->CR1 |= I2C_CR1_STOP;
 147
 148     return 0;
 149 }
 150
 151 int i2c_read(i2c_t *obj, int address, char *data, int length, int stop)
 152 {
 153     I2C_TypeDef *i2c = (I2C_TypeDef *)(obj->i2c);
 154     I2cHandle.Instance = (I2C_TypeDef *)(obj->i2c);
 155     int timeout;
 156     int count;
 157     int value;
 158
 159     i2c_start(obj);
 160
 161     // Wait until SB flag is set
 162     timeout = FLAG_TIMEOUT;
 163     while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_SB) == RESET) {
 164         timeout--;
 165         if (timeout == 0) {
 166             return -1;
 167         }
 168     }
 169
 170     i2c->DR = I2C_7BIT_ADD_READ(address);
 171
 172
 173     // Wait address is acknowledged
 174     timeout = FLAG_TIMEOUT;
 175     while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_ADDR) == RESET) {
 176         timeout--;
 177         if (timeout == 0) {
 178             return -1;
 179         }
 180     }
 181     __HAL_I2C_CLEAR_ADDRFLAG(&I2cHandle);
 182
 183     // Read all bytes except last one
 184     for (count = 0; count < (length - 1); count++) {
 185         value = i2c_byte_read(obj, 0);
 186         data[count] = (char)value;
 187     }
 188
 189     // If not repeated start, send stop.
 190     // Warning: must be done BEFORE the data is read.
 191     if (stop) {
 192         i2c_stop(obj);
 193     }
 194
 195     // Read the last byte
 196     value = i2c_byte_read(obj, 1);
 197     data[count] = (char)value;
 198
 199     return length;
 200 }
 201
 202 int i2c_write(i2c_t *obj, int address, const char *data, int length, int stop)
 203 {
 204     I2C_TypeDef *i2c = (I2C_TypeDef *)(obj->i2c);
 205     I2cHandle.Instance = (I2C_TypeDef *)(obj->i2c);
 206     int timeout;
 207     int count;
 208
 209     i2c_start(obj);
 210
 211     // Wait until SB flag is set
 212     timeout = FLAG_TIMEOUT;
 213     while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_SB) == RESET) {
 214         timeout--;
 215         if (timeout == 0) {
 216             return -1;
 217         }
 218     }
 219
 220     i2c->DR = I2C_7BIT_ADD_WRITE(address);
 221
 222
 223     // Wait address is acknowledged
 224     timeout = FLAG_TIMEOUT;
 225     while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_ADDR) == RESET) {
 226         timeout--;
 227         if (timeout == 0) {
 228             return -1;
 229         }
 230     }
 231     __HAL_I2C_CLEAR_ADDRFLAG(&I2cHandle);
 232
 233     for (count = 0; count < length; count++) {
 234         if (i2c_byte_write(obj, data[count]) != 1) {
 235             i2c_stop(obj);
 236             return -1;
 237         }
 238     }
 239
 240     // If not repeated start, send stop.
 241     if (stop) {
 242         i2c_stop(obj);
 243     }
 244
 245     return count;
 246 }
 247
 248 int i2c_byte_read(i2c_t *obj, int last)
 249 {
 250     I2C_TypeDef *i2c = (I2C_TypeDef *)(obj->i2c);
 251     int timeout;
 252
 253     if (last) {
 254         // Don't acknowledge the last byte
 255         i2c->CR1 &= ~I2C_CR1_ACK;
 256     } else {
 257         // Acknowledge the byte
 258         i2c->CR1 |= I2C_CR1_ACK;
 259     }
 260
 261     // Wait until the byte is received
 262     timeout = FLAG_TIMEOUT;
 263     while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_RXNE) == RESET) {
 264         if ((timeout--) == 0) {
 265             return -1;
 266         }
 267     }
 268
 269     return (int)i2c->DR;
 270 }
 271
 272 int i2c_byte_write(i2c_t *obj, int data)
 273 {
 274     I2C_TypeDef *i2c = (I2C_TypeDef *)(obj->i2c);
 275     int timeout;
 276
 277     i2c->DR = (uint8_t)data;
 278
 279     // Wait until the byte is transmitted
 280     timeout = FLAG_TIMEOUT;
 281     while ((__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_TXE) == RESET) &&
 282             (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_BTF) == RESET)) {
 283         if ((timeout--) == 0) {
 284             return 0;
 285         }
 286     }
 287
 288     return 1;
 289 }
 290
 291 void i2c_reset(i2c_t *obj)
 292 {
 293     int timeout;
 294
 295     // wait before reset
 296     timeout = LONG_TIMEOUT;
 297     while ((__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_BUSY)) && (timeout-- != 0));
 298
 299     if (obj->i2c == I2C_1) {
 300         __I2C1_FORCE_RESET();
 301         __I2C1_RELEASE_RESET();
 302     }
 303     if (obj->i2c == I2C_2) {
 304         __I2C2_FORCE_RESET();
 305         __I2C2_RELEASE_RESET();
 306     }
 307 }
 308
 309 #if DEVICE_I2CSLAVE
 310
 311 void i2c_slave_address(i2c_t *obj, int idx, uint32_t address, uint32_t mask)
 312 {
 313     I2C_TypeDef *i2c = (I2C_TypeDef *)(obj->i2c);
 314     uint16_t tmpreg = 0;
 315
 316     // Get the old register value
 317     tmpreg = i2c->OAR1;
 318     // Reset address bits
 319     tmpreg &= 0xFC00;
 320     // Set new address
 321     tmpreg |= (uint16_t)((uint16_t)address & (uint16_t)0x00FE); // 7-bits
 322     // Store the new register value
 323     i2c->OAR1 = tmpreg;
 324 }
 325
 326 void i2c_slave_mode(i2c_t *obj, int enable_slave)
 327 {
 328     I2cHandle.Instance = (I2C_TypeDef *)(obj->i2c);
 329     if (enable_slave) {
 330         obj->slave = 1;
 331         /* Enable Address Acknowledge */
 332         I2cHandle.Instance->CR1 |= I2C_CR1_ACK;
 333     }
 334 }
 335
 336 // See I2CSlave.h
 337 #define NoData         0 // the slave has not been addressed
 338 #define ReadAddressed  1 // the master has requested a read from this slave (slave = transmitter)
 339 #define WriteGeneral   2 // the master is writing to all slave
 340 #define WriteAddressed 3 // the master is writing to this slave (slave = receiver)
 341
 342 int i2c_slave_receive(i2c_t *obj)
 343 {
 344     int retValue = NoData;
 345
 346     if (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_BUSY) == 1) {
 347         if (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_ADDR) == 1) {
 348             if (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_TRA) == 1)
 349                 retValue = ReadAddressed;
 350             else
 351                 retValue = WriteAddressed;
 352
 353             __HAL_I2C_CLEAR_FLAG(&I2cHandle, I2C_FLAG_ADDR);
 354         }
 355     }
 356
 357     return (retValue);
 358 }
 359
 360 int i2c_slave_read(i2c_t *obj, char *data, int length)
 361 {
 362     uint32_t Timeout;
 363     int size = 0;
 364
 365     I2cHandle.Instance = (I2C_TypeDef *)(obj->i2c);
 366
 367     while (length > 0) {
 368         /* Wait until RXNE flag is set */
 369         // Wait until the byte is received
 370         Timeout = FLAG_TIMEOUT;
 371         while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_RXNE) == RESET) {
 372             Timeout--;
 373             if (Timeout == 0) {
 374                 return -1;
 375             }
 376         }
 377
 378         /* Read data from DR */
 379         (*data++) = I2cHandle.Instance->DR;
 380         length--;
 381         size++;
 382
 383         if ((__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_BTF) == SET) && (length != 0)) {
 384             /* Read data from DR */
 385             (*data++) = I2cHandle.Instance->DR;
 386             length--;
 387             size++;
 388         }
 389     }
 390
 391     /* Wait until STOP flag is set */
 392     Timeout = FLAG_TIMEOUT;
 393     while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_STOPF) == RESET) {
 394         Timeout--;
 395         if (Timeout == 0) {
 396             return -1;
 397         }
 398     }
 399
 400     /* Clear STOP flag */
 401     __HAL_I2C_CLEAR_STOPFLAG(&I2cHandle);
 402
 403     /* Wait until BUSY flag is reset */
 404     Timeout = FLAG_TIMEOUT;
 405     while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_BUSY) == SET) {
 406         Timeout--;
 407         if (Timeout == 0) {
 408             return -1;
 409         }
 410     }
 411
 412     return size;
 413 }
 414
 415 int i2c_slave_write(i2c_t *obj, const char *data, int length)
 416 {
 417     uint32_t Timeout;
 418     int size = 0;
 419
 420     I2cHandle.Instance = (I2C_TypeDef *)(obj->i2c);
 421
 422     while (length > 0) {
 423         /* Wait until TXE flag is set */
 424         Timeout = FLAG_TIMEOUT;
 425         while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_TXE) == RESET) {
 426             Timeout--;
 427             if (Timeout == 0) {
 428                 return -1;
 429             }
 430         }
 431
 432
 433         /* Write data to DR */
 434         I2cHandle.Instance->DR = (*data++);
 435         length--;
 436         size++;
 437
 438         if ((__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_BTF) == SET) && (length != 0)) {
 439             /* Write data to DR */
 440             I2cHandle.Instance->DR = (*data++);
 441             length--;
 442             size++;
 443         }
 444     }
 445
 446     /* Wait until AF flag is set */
 447     Timeout = FLAG_TIMEOUT;
 448     while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_AF) == RESET) {
 449         Timeout--;
 450         if (Timeout == 0) {
 451             return -1;
 452         }
 453     }
 454
 455
 456     /* Clear AF flag */
 457     __HAL_I2C_CLEAR_FLAG(&I2cHandle, I2C_FLAG_AF);
 458
 459
 460     /* Wait until BUSY flag is reset */
 461     Timeout = FLAG_TIMEOUT;
 462     while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_BUSY) == SET) {
 463         Timeout--;
 464         if (Timeout == 0) {
 465             return -1;
 466         }
 467     }
 468
 469     I2cHandle.State = HAL_I2C_STATE_READY;
 470
 471     /* Process Unlocked */
 472     __HAL_UNLOCK(&I2cHandle);
 473
 474     return size;
 475 }
 476
 477
 478 #endif // DEVICE_I2CSLAVE
 479
 480 #endif // DEVICE_I2C