diff options
Diffstat (limited to 'examples/imx7_colibri_m4/demo_apps/sensor_demo/common/i2c_xfer.c')
| -rw-r--r-- | examples/imx7_colibri_m4/demo_apps/sensor_demo/common/i2c_xfer.c | 326 |
1 files changed, 326 insertions, 0 deletions
diff --git a/examples/imx7_colibri_m4/demo_apps/sensor_demo/common/i2c_xfer.c b/examples/imx7_colibri_m4/demo_apps/sensor_demo/common/i2c_xfer.c new file mode 100644 index 0000000..b8410d4 --- /dev/null +++ b/examples/imx7_colibri_m4/demo_apps/sensor_demo/common/i2c_xfer.c @@ -0,0 +1,326 @@ +/* + * Copyright (c) 2015, Freescale Semiconductor, Inc. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without modification, + * are permitted provided that the following conditions are met: + * + * o Redistributions of source code must retain the above copyright notice, this list + * of conditions and the following disclaimer. + * + * o Redistributions in binary form must reproduce the above copyright notice, this + * list of conditions and the following disclaimer in the documentation and/or + * other materials provided with the distribution. + * + * o Neither the name of Freescale Semiconductor, Inc. nor the names of its + * contributors may be used to endorse or promote products derived from this + * software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED + * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE + * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR + * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES + * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; + * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON + * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS + * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ +#include "FreeRTOS.h" +#include "semphr.h" +#include "device_imx.h" +#include "i2c_imx.h" +#include "board.h" + +typedef struct _i2c_state { + const uint8_t* cmdBuff; /*!< The buffer of I2C command. */ + const uint8_t* txBuff; /*!< The buffer of data being sent.*/ + uint8_t* rxBuff; /*!< The buffer of received data. */ + uint32_t cmdSize; /*!< The remaining number of commands to be transmitted. */ + uint32_t txSize; /*!< The remaining number of bytes to be transmitted. */ + uint32_t rxSize; /*!< The remaining number of bytes to be received. */ + bool isBusy; /*!< True if there is an active transmission. */ + uint32_t operateDir; /*!< Overall I2C bus operating direction. */ + uint32_t currentDir; /*!< Current Data transfer direction. */ + uint32_t currentMode; /*!< Current I2C Bus role of this module. */ + SemaphoreHandle_t xSemaphore; /*!< I2C internal synchronize semaphore. */ +} i2c_state_t; + +/* I2C runtime state structure */ +static volatile i2c_state_t i2cState; + +void I2C_XFER_Config(i2c_init_config_t* initConfig) +{ + /* Initialize I2C state structure content. */ + i2cState.cmdBuff = 0; + i2cState.txBuff = 0; + i2cState.rxBuff = 0; + i2cState.cmdSize = 0; + i2cState.txSize = 0; + i2cState.rxSize = 0; + i2cState.isBusy = false; + i2cState.operateDir = i2cDirectionReceive; + i2cState.currentDir = i2cDirectionReceive; + i2cState.currentMode = i2cModeSlave; + i2cState.xSemaphore = xSemaphoreCreateBinary(); + + /* Initialize I2C baud rate, mode, transfer direction and slave address. */ + I2C_Init(BOARD_I2C_BASEADDR, initConfig); + + /* Set I2C Interrupt priority */ + NVIC_SetPriority(BOARD_I2C_IRQ_NUM, 3); + + /* Call core API to enable the IRQ. */ + NVIC_EnableIRQ(BOARD_I2C_IRQ_NUM); + + /* Finally, enable the I2C module */ + I2C_Enable(BOARD_I2C_BASEADDR); +} + +bool I2C_XFER_SendDataBlocking(const uint8_t* cmdBuff, uint32_t cmdSize, + const uint8_t* txBuffer, uint32_t txSize) +{ + if ((i2cState.isBusy) || (0 == txSize)) + return false; + + /* Initialize i2c transfer struct */ + i2cState.cmdBuff = cmdBuff; + i2cState.cmdSize = cmdSize; + i2cState.txBuff = txBuffer; + i2cState.txSize = txSize; + i2cState.isBusy = true; + i2cState.operateDir = i2cDirectionTransmit; + + /* Clear I2C interrupt flag to avoid spurious interrupt */ + I2C_ClearStatusFlag(BOARD_I2C_BASEADDR, i2cStatusInterrupt); + + if (I2C_GetStatusFlag(BOARD_I2C_BASEADDR, i2cStatusBusBusy)) + { + /* Reset i2c transfer state. */ + i2cState.operateDir = i2cDirectionReceive; + i2cState.isBusy = false; + return false; + } + + /* Set I2C work under Tx mode */ + I2C_SetDirMode(BOARD_I2C_BASEADDR, i2cDirectionTransmit); + i2cState.currentDir = i2cDirectionTransmit; + + /* Switch to Master Mode and Send Start Signal. */ + I2C_SetWorkMode(BOARD_I2C_BASEADDR, i2cModeMaster); + i2cState.currentMode = i2cModeMaster; + + if (0 != cmdSize) + { + I2C_WriteByte(BOARD_I2C_BASEADDR, *i2cState.cmdBuff); + i2cState.cmdBuff++; + i2cState.cmdSize--; + } + else + { + I2C_WriteByte(BOARD_I2C_BASEADDR, *i2cState.txBuff); + i2cState.txBuff++; + i2cState.txSize--; + } + + /* Enable I2C interrupt, subsequent data transfer will be handled in ISR. */ + I2C_SetIntCmd(BOARD_I2C_BASEADDR, true); + + /* Wait until send data finish. */ + xSemaphoreTake(i2cState.xSemaphore, portMAX_DELAY); + + return true; +} + +uint32_t I2C_XFER_GetSendStatus(void) +{ + return i2cState.txSize; +} + +bool I2C_XFER_ReceiveDataBlocking(const uint8_t* cmdBuff, uint32_t cmdSize, + uint8_t* rxBuffer, uint32_t rxSize) +{ + if ((i2cState.isBusy) || (0 == rxSize)) + return false; + + /* Initialize i2c transfer struct */ + i2cState.cmdBuff = cmdBuff; + i2cState.cmdSize = cmdSize; + i2cState.rxBuff = rxBuffer; + i2cState.rxSize = rxSize; + i2cState.isBusy = true; + i2cState.operateDir = i2cDirectionReceive; + + /* Clear I2C interrupt flag to avoid spurious interrupt */ + I2C_ClearStatusFlag(BOARD_I2C_BASEADDR, i2cStatusInterrupt); + + if (I2C_GetStatusFlag(BOARD_I2C_BASEADDR, i2cStatusBusBusy)) + { + /* Reset i2c transfer state. */ + i2cState.operateDir = i2cDirectionReceive; + i2cState.isBusy = false; + return false; + } + + /* Set I2C work under Tx mode */ + I2C_SetDirMode(BOARD_I2C_BASEADDR, i2cDirectionTransmit); + i2cState.currentDir = i2cDirectionTransmit; + + /* Switch to Master Mode and Send Start Signal. */ + I2C_SetWorkMode(BOARD_I2C_BASEADDR, i2cModeMaster); + i2cState.currentMode = i2cModeMaster; + + /* Is there command to be sent before receive data? */ + if (0 != i2cState.cmdSize) + { + if (1 == i2cState.cmdSize) + I2C_SendRepeatStart(BOARD_I2C_BASEADDR); + I2C_WriteByte(BOARD_I2C_BASEADDR, *i2cState.cmdBuff); + i2cState.cmdBuff++; + i2cState.cmdSize--; + } + else + { + /* Change to receive state. */ + I2C_SetDirMode(BOARD_I2C_BASEADDR, i2cDirectionReceive); + i2cState.currentDir = i2cDirectionReceive; + + if (1 == rxSize) + /* Send Nack */ + I2C_SetAckBit(BOARD_I2C_BASEADDR, false); + else + /* Send Ack */ + I2C_SetAckBit(BOARD_I2C_BASEADDR, true); + /* dummy read to clock in 1st byte */ + I2C_ReadByte(BOARD_I2C_BASEADDR); + } + + /* Enable I2C interrupt, subsequent data transfer will be handled in ISR. */ + I2C_SetIntCmd(BOARD_I2C_BASEADDR, true); + + /* Wait until receive data finish. */ + xSemaphoreTake(i2cState.xSemaphore, portMAX_DELAY); + + return true; +} + +uint32_t I2C_XFER_GetReceiveStatus(void) +{ + return i2cState.rxSize; +} + +void BOARD_I2C_HANDLER(void) +{ + BaseType_t xHigherPriorityTaskWoken = pdFALSE; + + /* Clear interrupt flag. */ + I2C_ClearStatusFlag(BOARD_I2C_BASEADDR, i2cStatusInterrupt); + + /* Exit the ISR if no transfer is happening for this instance. */ + if (!i2cState.isBusy) + return; + + if (i2cModeMaster == i2cState.currentMode) + { + if (i2cDirectionTransmit == i2cState.currentDir) + { + if ((I2C_GetStatusFlag(BOARD_I2C_BASEADDR, i2cStatusReceivedAck)) || + ((0 == i2cState.txSize) && (0 == i2cState.cmdSize))) + { + if ((i2cDirectionTransmit == i2cState.operateDir) || + (I2C_GetStatusFlag(BOARD_I2C_BASEADDR, i2cStatusReceivedAck))) + { + /* Switch to Slave mode and Generate a Stop Signal. */ + I2C_SetWorkMode(BOARD_I2C_BASEADDR, i2cModeSlave); + i2cState.currentMode = i2cModeSlave; + + /* Switch back to Rx direction. */ + I2C_SetDirMode(BOARD_I2C_BASEADDR, i2cDirectionReceive); + i2cState.currentDir = i2cDirectionReceive; + + /* Close I2C interrupt. */ + I2C_SetIntCmd(BOARD_I2C_BASEADDR, false); + /* Release I2C Bus. */ + i2cState.isBusy = false; + xSemaphoreGiveFromISR(i2cState.xSemaphore, &xHigherPriorityTaskWoken); + } + else + { + /* Switch back to Rx direction. */ + I2C_SetDirMode(BOARD_I2C_BASEADDR, i2cDirectionReceive); + i2cState.currentDir = i2cDirectionReceive; + + if (1 == i2cState.rxSize) + /* Send Nack */ + I2C_SetAckBit(BOARD_I2C_BASEADDR, false); + else + /* Send Ack */ + I2C_SetAckBit(BOARD_I2C_BASEADDR, true); + /* dummy read to clock in 1st byte */ + *i2cState.rxBuff = I2C_ReadByte(BOARD_I2C_BASEADDR); + } + } + else + { + if (0 != i2cState.cmdSize) + { + if ((1 == i2cState.cmdSize) && (i2cDirectionReceive == i2cState.operateDir)) + I2C_SendRepeatStart(BOARD_I2C_BASEADDR); + I2C_WriteByte(BOARD_I2C_BASEADDR, *i2cState.cmdBuff); + i2cState.cmdBuff++; + i2cState.cmdSize--; + } + else + { + I2C_WriteByte(BOARD_I2C_BASEADDR, *i2cState.txBuff); + i2cState.txBuff++; + i2cState.txSize--; + } + } + } + else + { + /* Normal read operation. */ + if (2 == i2cState.rxSize) + /* Send Nack */ + I2C_SetAckBit(BOARD_I2C_BASEADDR, false); + else + /* Send Nack */ + I2C_SetAckBit(BOARD_I2C_BASEADDR, true); + + if (1 == i2cState.rxSize) + { + /* Switch back to Tx direction to avoid additional I2C bus read. */ + I2C_SetDirMode(BOARD_I2C_BASEADDR, i2cDirectionTransmit); + i2cState.currentDir = i2cDirectionTransmit; + } + *i2cState.rxBuff = I2C_ReadByte(BOARD_I2C_BASEADDR); + i2cState.rxBuff++; + i2cState.rxSize--; + + /* receive finished. */ + if (0 == i2cState.rxSize) + { + /* Switch to Slave mode and Generate a Stop Signal. */ + I2C_SetWorkMode(BOARD_I2C_BASEADDR, i2cModeSlave); + i2cState.currentMode = i2cModeSlave; + + /* Switch back to Rx direction. */ + I2C_SetDirMode(BOARD_I2C_BASEADDR, i2cDirectionReceive); + i2cState.currentDir = i2cDirectionReceive; + + /* Close I2C interrupt. */ + I2C_SetIntCmd(BOARD_I2C_BASEADDR, false); + /* Release I2C Bus. */ + i2cState.isBusy = false; + /* Release I2C Sem4 */ + xSemaphoreGiveFromISR(i2cState.xSemaphore, &xHigherPriorityTaskWoken); + } + } + } +} + +/******************************************************************************* + * EOF + ******************************************************************************/ |