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authorgdisirio <gdisirio@35acf78f-673a-0410-8e92-d51de3d6d3f4>2014-01-24 14:25:46 +0000
committergdisirio <gdisirio@35acf78f-673a-0410-8e92-d51de3d6d3f4>2014-01-24 14:25:46 +0000
commit156a9e9fa71badb88476ac2bbc1219587ea8e7bb (patch)
tree8e6adb5c968a6ac67a188c094ca062e196ddf19f /os/hal/ports/STM32/LLD/I2Cv1
parentcd98598fd8dda30d4ff002a451eae569d8a56f1e (diff)
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git-svn-id: svn://svn.code.sf.net/p/chibios/svn/branches/kernel_3_dev@6643 35acf78f-673a-0410-8e92-d51de3d6d3f4
Diffstat (limited to 'os/hal/ports/STM32/LLD/I2Cv1')
-rw-r--r--os/hal/ports/STM32/LLD/I2Cv1/i2c_lld.c855
-rw-r--r--os/hal/ports/STM32/LLD/I2Cv1/i2c_lld.h512
2 files changed, 1367 insertions, 0 deletions
diff --git a/os/hal/ports/STM32/LLD/I2Cv1/i2c_lld.c b/os/hal/ports/STM32/LLD/I2Cv1/i2c_lld.c
new file mode 100644
index 000000000..89b80396f
--- /dev/null
+++ b/os/hal/ports/STM32/LLD/I2Cv1/i2c_lld.c
@@ -0,0 +1,855 @@
+/*
+ ChibiOS/RT - Copyright (C) 2006-2013 Giovanni Di Sirio
+
+ 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.
+*/
+/*
+ Concepts and parts of this file have been contributed by Uladzimir Pylinsky
+ aka barthess.
+ */
+
+/**
+ * @file STM32/I2Cv1/i2c_lld.c
+ * @brief STM32 I2C subsystem low level driver source.
+ *
+ * @addtogroup I2C
+ * @{
+ */
+
+#include "hal.h"
+
+#if HAL_USE_I2C || defined(__DOXYGEN__)
+
+/*===========================================================================*/
+/* Driver local definitions. */
+/*===========================================================================*/
+
+#define I2C1_RX_DMA_CHANNEL \
+ STM32_DMA_GETCHANNEL(STM32_I2C_I2C1_RX_DMA_STREAM, \
+ STM32_I2C1_RX_DMA_CHN)
+
+#define I2C1_TX_DMA_CHANNEL \
+ STM32_DMA_GETCHANNEL(STM32_I2C_I2C1_TX_DMA_STREAM, \
+ STM32_I2C1_TX_DMA_CHN)
+
+#define I2C2_RX_DMA_CHANNEL \
+ STM32_DMA_GETCHANNEL(STM32_I2C_I2C2_RX_DMA_STREAM, \
+ STM32_I2C2_RX_DMA_CHN)
+
+#define I2C2_TX_DMA_CHANNEL \
+ STM32_DMA_GETCHANNEL(STM32_I2C_I2C2_TX_DMA_STREAM, \
+ STM32_I2C2_TX_DMA_CHN)
+
+#define I2C3_RX_DMA_CHANNEL \
+ STM32_DMA_GETCHANNEL(STM32_I2C_I2C3_RX_DMA_STREAM, \
+ STM32_I2C3_RX_DMA_CHN)
+
+#define I2C3_TX_DMA_CHANNEL \
+ STM32_DMA_GETCHANNEL(STM32_I2C_I2C3_TX_DMA_STREAM, \
+ STM32_I2C3_TX_DMA_CHN)
+
+/*===========================================================================*/
+/* Driver constants. */
+/*===========================================================================*/
+
+#define I2C_EV5_MASTER_MODE_SELECT \
+ ((uint32_t)(((I2C_SR2_MSL | I2C_SR2_BUSY) << 16) | I2C_SR1_SB))
+
+#define I2C_EV6_MASTER_TRA_MODE_SELECTED \
+ ((uint32_t)(((I2C_SR2_MSL | I2C_SR2_BUSY | I2C_SR2_TRA) << 16) | \
+ I2C_SR1_ADDR | I2C_SR1_TXE))
+
+#define I2C_EV6_MASTER_REC_MODE_SELECTED \
+ ((uint32_t)(((I2C_SR2_MSL | I2C_SR2_BUSY)<< 16) | I2C_SR1_ADDR))
+
+#define I2C_EV8_2_MASTER_BYTE_TRANSMITTED \
+ ((uint32_t)(((I2C_SR2_MSL | I2C_SR2_BUSY | I2C_SR2_TRA) << 16) | \
+ I2C_SR1_BTF | I2C_SR1_TXE))
+
+#define I2C_EV9_MASTER_ADD10 \
+ ((uint32_t)(((I2C_SR2_MSL | I2C_SR2_BUSY) << 16) | I2C_SR1_ADD10))
+
+#define I2C_EV_MASK 0x00FFFFFF
+
+#define I2C_ERROR_MASK \
+ ((uint16_t)(I2C_SR1_BERR | I2C_SR1_ARLO | I2C_SR1_AF | I2C_SR1_OVR | \
+ I2C_SR1_PECERR | I2C_SR1_TIMEOUT | I2C_SR1_SMBALERT))
+
+/*===========================================================================*/
+/* Driver exported variables. */
+/*===========================================================================*/
+
+/** @brief I2C1 driver identifier.*/
+#if STM32_I2C_USE_I2C1 || defined(__DOXYGEN__)
+I2CDriver I2CD1;
+#endif
+
+/** @brief I2C2 driver identifier.*/
+#if STM32_I2C_USE_I2C2 || defined(__DOXYGEN__)
+I2CDriver I2CD2;
+#endif
+
+/** @brief I2C3 driver identifier.*/
+#if STM32_I2C_USE_I2C3 || defined(__DOXYGEN__)
+I2CDriver I2CD3;
+#endif
+
+/*===========================================================================*/
+/* Driver local variables and types. */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Driver local functions. */
+/*===========================================================================*/
+
+/**
+ * @brief Aborts an I2C transaction.
+ *
+ * @param[in] i2cp pointer to the @p I2CDriver object
+ *
+ * @notapi
+ */
+static void i2c_lld_abort_operation(I2CDriver *i2cp) {
+ I2C_TypeDef *dp = i2cp->i2c;
+
+ /* Stops the I2C peripheral.*/
+ dp->CR1 = I2C_CR1_SWRST;
+ dp->CR1 = 0;
+ dp->CR2 = 0;
+ dp->SR1 = 0;
+
+ /* Stops the associated DMA streams.*/
+ dmaStreamDisable(i2cp->dmatx);
+ dmaStreamDisable(i2cp->dmarx);
+}
+
+/**
+ * @brief Set clock speed.
+ *
+ * @param[in] i2cp pointer to the @p I2CDriver object
+ *
+ * @notapi
+ */
+static void i2c_lld_set_clock(I2CDriver *i2cp) {
+ I2C_TypeDef *dp = i2cp->i2c;
+ uint16_t regCCR, clock_div;
+ int32_t clock_speed = i2cp->config->clock_speed;
+ i2cdutycycle_t duty = i2cp->config->duty_cycle;
+
+ osalDbgCheck((i2cp != NULL) &&
+ (clock_speed > 0) &&
+ (clock_speed <= 4000000));
+
+ /* CR2 Configuration.*/
+ dp->CR2 &= (uint16_t)~I2C_CR2_FREQ;
+ dp->CR2 |= (uint16_t)I2C_CLK_FREQ;
+
+ /* CCR Configuration.*/
+ regCCR = 0;
+ clock_div = I2C_CCR_CCR;
+
+ if (clock_speed <= 100000) {
+ /* Configure clock_div in standard mode.*/
+ osalDbgAssert(duty == STD_DUTY_CYCLE, "invalid standard mode duty cycle");
+
+ /* Standard mode clock_div calculate: Tlow/Thigh = 1/1.*/
+ osalDbgAssert((STM32_PCLK1 % (clock_speed * 2)) == 0,
+ "PCLK1 must be divisible without remainder");
+ clock_div = (uint16_t)(STM32_PCLK1 / (clock_speed * 2));
+
+ osalDbgAssert(clock_div >= 0x04,
+ "clock divider less then 0x04 not allowed");
+ regCCR |= (clock_div & I2C_CCR_CCR);
+
+ /* Sets the Maximum Rise Time for standard mode.*/
+ dp->TRISE = I2C_CLK_FREQ + 1;
+ }
+ else if (clock_speed <= 400000) {
+ /* Configure clock_div in fast mode.*/
+ osalDbgAssert((duty == FAST_DUTY_CYCLE_2) ||
+ (duty == FAST_DUTY_CYCLE_16_9),
+ "invalid fast mode duty cycle");
+
+ if (duty == FAST_DUTY_CYCLE_2) {
+ /* Fast mode clock_div calculate: Tlow/Thigh = 2/1.*/
+ osalDbgAssert((STM32_PCLK1 % (clock_speed * 3)) == 0,
+ "PCLK1 must be divided without remainder");
+ clock_div = (uint16_t)(STM32_PCLK1 / (clock_speed * 3));
+ }
+ else if (duty == FAST_DUTY_CYCLE_16_9) {
+ /* Fast mode clock_div calculate: Tlow/Thigh = 16/9.*/
+ osalDbgAssert((STM32_PCLK1 % (clock_speed * 25)) == 0,
+ "PCLK1 must be divided without remainder");
+ clock_div = (uint16_t)(STM32_PCLK1 / (clock_speed * 25));
+ regCCR |= I2C_CCR_DUTY;
+ }
+
+ osalDbgAssert(clock_div >= 0x01,
+ "clock divider less then 0x04 not allowed");
+ regCCR |= (I2C_CCR_FS | (clock_div & I2C_CCR_CCR));
+
+ /* Sets the Maximum Rise Time for fast mode.*/
+ dp->TRISE = (I2C_CLK_FREQ * 300 / 1000) + 1;
+ }
+
+ osalDbgAssert((clock_div <= I2C_CCR_CCR), "the selected clock is too low");
+
+ dp->CCR = regCCR;
+}
+
+/**
+ * @brief Set operation mode of I2C hardware.
+ *
+ * @param[in] i2cp pointer to the @p I2CDriver object
+ *
+ * @notapi
+ */
+static void i2c_lld_set_opmode(I2CDriver *i2cp) {
+ I2C_TypeDef *dp = i2cp->i2c;
+ i2copmode_t opmode = i2cp->config->op_mode;
+ uint16_t regCR1;
+
+ regCR1 = dp->CR1;
+ switch (opmode) {
+ case OPMODE_I2C:
+ regCR1 &= (uint16_t)~(I2C_CR1_SMBUS|I2C_CR1_SMBTYPE);
+ break;
+ case OPMODE_SMBUS_DEVICE:
+ regCR1 |= I2C_CR1_SMBUS;
+ regCR1 &= (uint16_t)~(I2C_CR1_SMBTYPE);
+ break;
+ case OPMODE_SMBUS_HOST:
+ regCR1 |= (I2C_CR1_SMBUS|I2C_CR1_SMBTYPE);
+ break;
+ }
+ dp->CR1 = regCR1;
+}
+
+/**
+ * @brief I2C shared ISR code.
+ *
+ * @param[in] i2cp pointer to the @p I2CDriver object
+ *
+ * @notapi
+ */
+static void i2c_lld_serve_event_interrupt(I2CDriver *i2cp) {
+ I2C_TypeDef *dp = i2cp->i2c;
+ uint32_t regSR2 = dp->SR2;
+ uint32_t event = dp->SR1;
+
+ /* Interrupts are disabled just before dmaStreamEnable() because there
+ is no need of interrupts until next transaction begin. All the work is
+ done by the DMA.*/
+ switch (I2C_EV_MASK & (event | (regSR2 << 16))) {
+ case I2C_EV5_MASTER_MODE_SELECT:
+ if ((i2cp->addr >> 8) > 0) {
+ /* 10-bit address: 1 1 1 1 0 X X R/W */
+ dp->DR = 0xF0 | (0x6 & (i2cp->addr >> 8)) | (0x1 & i2cp->addr);
+ } else {
+ dp->DR = i2cp->addr;
+ }
+ break;
+ case I2C_EV9_MASTER_ADD10:
+ /* Set second addr byte (10-bit addressing)*/
+ dp->DR = (0xFF & (i2cp->addr >> 1));
+ break;
+ case I2C_EV6_MASTER_REC_MODE_SELECTED:
+ dp->CR2 &= ~I2C_CR2_ITEVTEN;
+ dmaStreamEnable(i2cp->dmarx);
+ dp->CR2 |= I2C_CR2_LAST; /* Needed in receiver mode. */
+ if (dmaStreamGetTransactionSize(i2cp->dmarx) < 2)
+ dp->CR1 &= ~I2C_CR1_ACK;
+ break;
+ case I2C_EV6_MASTER_TRA_MODE_SELECTED:
+ dp->CR2 &= ~I2C_CR2_ITEVTEN;
+ dmaStreamEnable(i2cp->dmatx);
+ break;
+ case I2C_EV8_2_MASTER_BYTE_TRANSMITTED:
+ /* Catches BTF event after the end of transmission.*/
+ if (dmaStreamGetTransactionSize(i2cp->dmarx) > 0) {
+ /* Starts "read after write" operation, LSB = 1 -> receive.*/
+ i2cp->addr |= 0x01;
+ dp->CR1 |= I2C_CR1_START | I2C_CR1_ACK;
+ return;
+ }
+ dp->CR2 &= ~I2C_CR2_ITEVTEN;
+ dp->CR1 |= I2C_CR1_STOP;
+ _i2c_wakeup_isr(i2cp);
+ break;
+ default:
+ break;
+ }
+ /* Clear ADDR flag. */
+ if (event & (I2C_SR1_ADDR | I2C_SR1_ADD10))
+ (void)dp->SR2;
+}
+
+/**
+ * @brief DMA RX end IRQ handler.
+ *
+ * @param[in] i2cp pointer to the @p I2CDriver object
+ * @param[in] flags pre-shifted content of the ISR register
+ *
+ * @notapi
+ */
+static void i2c_lld_serve_rx_end_irq(I2CDriver *i2cp, uint32_t flags) {
+ I2C_TypeDef *dp = i2cp->i2c;
+
+ /* DMA errors handling.*/
+#if defined(STM32_I2C_DMA_ERROR_HOOK)
+ if ((flags & (STM32_DMA_ISR_TEIF | STM32_DMA_ISR_DMEIF)) != 0) {
+ STM32_I2C_DMA_ERROR_HOOK(i2cp);
+ }
+#else
+ (void)flags;
+#endif
+
+ dmaStreamDisable(i2cp->dmarx);
+
+ dp->CR2 &= ~I2C_CR2_LAST;
+ dp->CR1 &= ~I2C_CR1_ACK;
+ dp->CR1 |= I2C_CR1_STOP;
+ _i2c_wakeup_isr(i2cp);
+}
+
+/**
+ * @brief DMA TX end IRQ handler.
+ *
+ * @param[in] i2cp pointer to the @p I2CDriver object
+ *
+ * @notapi
+ */
+static void i2c_lld_serve_tx_end_irq(I2CDriver *i2cp, uint32_t flags) {
+ I2C_TypeDef *dp = i2cp->i2c;
+
+ /* DMA errors handling.*/
+#if defined(STM32_I2C_DMA_ERROR_HOOK)
+ if ((flags & (STM32_DMA_ISR_TEIF | STM32_DMA_ISR_DMEIF)) != 0) {
+ STM32_I2C_DMA_ERROR_HOOK(i2cp);
+ }
+#else
+ (void)flags;
+#endif
+
+ dmaStreamDisable(i2cp->dmatx);
+ /* Enables interrupts to catch BTF event meaning transmission part complete.
+ Interrupt handler will decide to generate STOP or to begin receiving part
+ of R/W transaction itself.*/
+ dp->CR2 |= I2C_CR2_ITEVTEN;
+}
+
+/**
+ * @brief I2C error handler.
+ *
+ * @param[in] i2cp pointer to the @p I2CDriver object
+ * @param[in] sr content of the SR1 register to be decoded
+ *
+ * @notapi
+ */
+static void i2c_lld_serve_error_interrupt(I2CDriver *i2cp, uint16_t sr) {
+
+ /* Clears interrupt flags just to be safe.*/
+ dmaStreamDisable(i2cp->dmatx);
+ dmaStreamDisable(i2cp->dmarx);
+
+ i2cp->errors = I2C_NO_ERROR;
+
+ if (sr & I2C_SR1_BERR) /* Bus error. */
+ i2cp->errors |= I2C_BUS_ERROR;
+
+ if (sr & I2C_SR1_ARLO) /* Arbitration lost. */
+ i2cp->errors |= I2C_ARBITRATION_LOST;
+
+ if (sr & I2C_SR1_AF) { /* Acknowledge fail. */
+ i2cp->i2c->CR2 &= ~I2C_CR2_ITEVTEN;
+ i2cp->i2c->CR1 |= I2C_CR1_STOP; /* Setting stop bit. */
+ i2cp->errors |= I2C_ACK_FAILURE;
+ }
+
+ if (sr & I2C_SR1_OVR) /* Overrun. */
+ i2cp->errors |= I2C_OVERRUN;
+
+ if (sr & I2C_SR1_TIMEOUT) /* SMBus Timeout. */
+ i2cp->errors |= I2C_TIMEOUT;
+
+ if (sr & I2C_SR1_PECERR) /* PEC error. */
+ i2cp->errors |= I2C_PEC_ERROR;
+
+ if (sr & I2C_SR1_SMBALERT) /* SMBus alert. */
+ i2cp->errors |= I2C_SMB_ALERT;
+
+ /* If some error has been identified then sends wakes the waiting thread.*/
+ if (i2cp->errors != I2C_NO_ERROR)
+ _i2c_wakeup_error_isr(i2cp);
+}
+
+/*===========================================================================*/
+/* Driver interrupt handlers. */
+/*===========================================================================*/
+
+#if STM32_I2C_USE_I2C1 || defined(__DOXYGEN__)
+/**
+ * @brief I2C1 event interrupt handler.
+ *
+ * @notapi
+ */
+OSAL_IRQ_HANDLER(I2C1_EV_IRQHandler) {
+
+ OSAL_IRQ_PROLOGUE();
+
+ i2c_lld_serve_event_interrupt(&I2CD1);
+
+ OSAL_IRQ_EPILOGUE();
+}
+
+/**
+ * @brief I2C1 error interrupt handler.
+ */
+OSAL_IRQ_HANDLER(I2C1_ER_IRQHandler) {
+ uint16_t sr = I2CD1.i2c->SR1;
+
+ OSAL_IRQ_PROLOGUE();
+
+ I2CD1.i2c->SR1 = ~(sr & I2C_ERROR_MASK);
+ i2c_lld_serve_error_interrupt(&I2CD1, sr);
+
+ OSAL_IRQ_EPILOGUE();
+}
+#endif /* STM32_I2C_USE_I2C1 */
+
+#if STM32_I2C_USE_I2C2 || defined(__DOXYGEN__)
+/**
+ * @brief I2C2 event interrupt handler.
+ *
+ * @notapi
+ */
+OSAL_IRQ_HANDLER(I2C2_EV_IRQHandler) {
+
+ OSAL_IRQ_PROLOGUE();
+
+ i2c_lld_serve_event_interrupt(&I2CD2);
+
+ OSAL_IRQ_EPILOGUE();
+}
+
+/**
+ * @brief I2C2 error interrupt handler.
+ *
+ * @notapi
+ */
+OSAL_IRQ_HANDLER(I2C2_ER_IRQHandler) {
+ uint16_t sr = I2CD2.i2c->SR1;
+
+ OSAL_IRQ_PROLOGUE();
+
+ I2CD2.i2c->SR1 = ~(sr & I2C_ERROR_MASK);
+ i2c_lld_serve_error_interrupt(&I2CD2, sr);
+
+ OSAL_IRQ_EPILOGUE();
+}
+#endif /* STM32_I2C_USE_I2C2 */
+
+#if STM32_I2C_USE_I2C3 || defined(__DOXYGEN__)
+/**
+ * @brief I2C3 event interrupt handler.
+ *
+ * @notapi
+ */
+OSAL_IRQ_HANDLER(I2C3_EV_IRQHandler) {
+
+ OSAL_IRQ_PROLOGUE();
+
+ i2c_lld_serve_event_interrupt(&I2CD3);
+
+ OSAL_IRQ_EPILOGUE();
+}
+
+/**
+ * @brief I2C3 error interrupt handler.
+ *
+ * @notapi
+ */
+OSAL_IRQ_HANDLER(I2C3_ER_IRQHandler) {
+ uint16_t sr = I2CD3.i2c->SR1;
+
+ OSAL_IRQ_PROLOGUE();
+
+ I2CD3.i2c->SR1 = ~(sr & I2C_ERROR_MASK);
+ i2c_lld_serve_error_interrupt(&I2CD3, sr);
+
+ OSAL_IRQ_EPILOGUE();
+}
+#endif /* STM32_I2C_USE_I2C3 */
+
+/*===========================================================================*/
+/* Driver exported functions. */
+/*===========================================================================*/
+
+/**
+ * @brief Low level I2C driver initialization.
+ *
+ * @notapi
+ */
+void i2c_lld_init(void) {
+
+#if STM32_I2C_USE_I2C1
+ i2cObjectInit(&I2CD1);
+ I2CD1.thread = NULL;
+ I2CD1.i2c = I2C1;
+ I2CD1.dmarx = STM32_DMA_STREAM(STM32_I2C_I2C1_RX_DMA_STREAM);
+ I2CD1.dmatx = STM32_DMA_STREAM(STM32_I2C_I2C1_TX_DMA_STREAM);
+#endif /* STM32_I2C_USE_I2C1 */
+
+#if STM32_I2C_USE_I2C2
+ i2cObjectInit(&I2CD2);
+ I2CD2.thread = NULL;
+ I2CD2.i2c = I2C2;
+ I2CD2.dmarx = STM32_DMA_STREAM(STM32_I2C_I2C2_RX_DMA_STREAM);
+ I2CD2.dmatx = STM32_DMA_STREAM(STM32_I2C_I2C2_TX_DMA_STREAM);
+#endif /* STM32_I2C_USE_I2C2 */
+
+#if STM32_I2C_USE_I2C3
+ i2cObjectInit(&I2CD3);
+ I2CD3.thread = NULL;
+ I2CD3.i2c = I2C3;
+ I2CD3.dmarx = STM32_DMA_STREAM(STM32_I2C_I2C3_RX_DMA_STREAM);
+ I2CD3.dmatx = STM32_DMA_STREAM(STM32_I2C_I2C3_TX_DMA_STREAM);
+#endif /* STM32_I2C_USE_I2C3 */
+}
+
+/**
+ * @brief Configures and activates the I2C peripheral.
+ *
+ * @param[in] i2cp pointer to the @p I2CDriver object
+ *
+ * @notapi
+ */
+void i2c_lld_start(I2CDriver *i2cp) {
+ I2C_TypeDef *dp = i2cp->i2c;
+
+ i2cp->txdmamode = STM32_DMA_CR_PSIZE_BYTE | STM32_DMA_CR_MSIZE_BYTE |
+ STM32_DMA_CR_MINC | STM32_DMA_CR_DMEIE |
+ STM32_DMA_CR_TEIE | STM32_DMA_CR_TCIE |
+ STM32_DMA_CR_DIR_M2P;
+ i2cp->rxdmamode = STM32_DMA_CR_PSIZE_BYTE | STM32_DMA_CR_MSIZE_BYTE |
+ STM32_DMA_CR_MINC | STM32_DMA_CR_DMEIE |
+ STM32_DMA_CR_TEIE | STM32_DMA_CR_TCIE |
+ STM32_DMA_CR_DIR_P2M;
+
+ /* If in stopped state then enables the I2C and DMA clocks.*/
+ if (i2cp->state == I2C_STOP) {
+
+#if STM32_I2C_USE_I2C1
+ if (&I2CD1 == i2cp) {
+ bool b;
+
+ rccResetI2C1();
+ b = dmaStreamAllocate(i2cp->dmarx,
+ STM32_I2C_I2C1_IRQ_PRIORITY,
+ (stm32_dmaisr_t)i2c_lld_serve_rx_end_irq,
+ (void *)i2cp);
+ osalDbgAssert(!b, "stream already allocated");
+ b = dmaStreamAllocate(i2cp->dmatx,
+ STM32_I2C_I2C1_IRQ_PRIORITY,
+ (stm32_dmaisr_t)i2c_lld_serve_tx_end_irq,
+ (void *)i2cp);
+ osalDbgAssert(!b, "stream already allocated");
+ rccEnableI2C1(FALSE);
+ nvicEnableVector(I2C1_EV_IRQn, STM32_I2C_I2C1_IRQ_PRIORITY);
+ nvicEnableVector(I2C1_ER_IRQn, STM32_I2C_I2C1_IRQ_PRIORITY);
+
+ i2cp->rxdmamode |= STM32_DMA_CR_CHSEL(I2C1_RX_DMA_CHANNEL) |
+ STM32_DMA_CR_PL(STM32_I2C_I2C1_DMA_PRIORITY);
+ i2cp->txdmamode |= STM32_DMA_CR_CHSEL(I2C1_TX_DMA_CHANNEL) |
+ STM32_DMA_CR_PL(STM32_I2C_I2C1_DMA_PRIORITY);
+ }
+#endif /* STM32_I2C_USE_I2C1 */
+
+#if STM32_I2C_USE_I2C2
+ if (&I2CD2 == i2cp) {
+ bool b;
+
+ rccResetI2C2();
+ b = dmaStreamAllocate(i2cp->dmarx,
+ STM32_I2C_I2C2_IRQ_PRIORITY,
+ (stm32_dmaisr_t)i2c_lld_serve_rx_end_irq,
+ (void *)i2cp);
+ osalDbgAssert(!b, "stream already allocated");
+ b = dmaStreamAllocate(i2cp->dmatx,
+ STM32_I2C_I2C2_IRQ_PRIORITY,
+ (stm32_dmaisr_t)i2c_lld_serve_tx_end_irq,
+ (void *)i2cp);
+ osalDbgAssert(!b, "stream already allocated");
+ rccEnableI2C2(FALSE);
+ nvicEnableVector(I2C2_EV_IRQn, STM32_I2C_I2C2_IRQ_PRIORITY);
+ nvicEnableVector(I2C2_ER_IRQn, STM32_I2C_I2C2_IRQ_PRIORITY);
+
+ i2cp->rxdmamode |= STM32_DMA_CR_CHSEL(I2C2_RX_DMA_CHANNEL) |
+ STM32_DMA_CR_PL(STM32_I2C_I2C2_DMA_PRIORITY);
+ i2cp->txdmamode |= STM32_DMA_CR_CHSEL(I2C2_TX_DMA_CHANNEL) |
+ STM32_DMA_CR_PL(STM32_I2C_I2C2_DMA_PRIORITY);
+ }
+#endif /* STM32_I2C_USE_I2C2 */
+
+#if STM32_I2C_USE_I2C3
+ if (&I2CD3 == i2cp) {
+ bool b;
+
+ rccResetI2C3();
+ b = dmaStreamAllocate(i2cp->dmarx,
+ STM32_I2C_I2C3_IRQ_PRIORITY,
+ (stm32_dmaisr_t)i2c_lld_serve_rx_end_irq,
+ (void *)i2cp);
+ osalDbgAssert(!b, "stream already allocated");
+ b = dmaStreamAllocate(i2cp->dmatx,
+ STM32_I2C_I2C3_IRQ_PRIORITY,
+ (stm32_dmaisr_t)i2c_lld_serve_tx_end_irq,
+ (void *)i2cp);
+ osalDbgAssert(!b, "stream already allocated");
+ rccEnableI2C3(FALSE);
+ nvicEnableVector(I2C3_EV_IRQn, STM32_I2C_I2C3_IRQ_PRIORITY);
+ nvicEnableVector(I2C3_ER_IRQn, STM32_I2C_I2C3_IRQ_PRIORITY);
+
+ i2cp->rxdmamode |= STM32_DMA_CR_CHSEL(I2C3_RX_DMA_CHANNEL) |
+ STM32_DMA_CR_PL(STM32_I2C_I2C3_DMA_PRIORITY);
+ i2cp->txdmamode |= STM32_DMA_CR_CHSEL(I2C3_TX_DMA_CHANNEL) |
+ STM32_DMA_CR_PL(STM32_I2C_I2C3_DMA_PRIORITY);
+ }
+#endif /* STM32_I2C_USE_I2C3 */
+ }
+
+ /* I2C registers pointed by the DMA.*/
+ dmaStreamSetPeripheral(i2cp->dmarx, &dp->DR);
+ dmaStreamSetPeripheral(i2cp->dmatx, &dp->DR);
+
+ /* Reset i2c peripheral.*/
+ dp->CR1 = I2C_CR1_SWRST;
+ dp->CR1 = 0;
+ dp->CR2 = I2C_CR2_ITERREN | I2C_CR2_DMAEN;
+
+ /* Setup I2C parameters.*/
+ i2c_lld_set_clock(i2cp);
+ i2c_lld_set_opmode(i2cp);
+
+ /* Ready to go.*/
+ dp->CR1 |= I2C_CR1_PE;
+}
+
+/**
+ * @brief Deactivates the I2C peripheral.
+ *
+ * @param[in] i2cp pointer to the @p I2CDriver object
+ *
+ * @notapi
+ */
+void i2c_lld_stop(I2CDriver *i2cp) {
+
+ /* If not in stopped state then disables the I2C clock.*/
+ if (i2cp->state != I2C_STOP) {
+
+ /* I2C disable.*/
+ i2c_lld_abort_operation(i2cp);
+ dmaStreamRelease(i2cp->dmatx);
+ dmaStreamRelease(i2cp->dmarx);
+
+#if STM32_I2C_USE_I2C1
+ if (&I2CD1 == i2cp) {
+ nvicDisableVector(I2C1_EV_IRQn);
+ nvicDisableVector(I2C1_ER_IRQn);
+ rccDisableI2C1(FALSE);
+ }
+#endif
+
+#if STM32_I2C_USE_I2C2
+ if (&I2CD2 == i2cp) {
+ nvicDisableVector(I2C2_EV_IRQn);
+ nvicDisableVector(I2C2_ER_IRQn);
+ rccDisableI2C2(FALSE);
+ }
+#endif
+
+#if STM32_I2C_USE_I2C3
+ if (&I2CD3 == i2cp) {
+ nvicDisableVector(I2C3_EV_IRQn);
+ nvicDisableVector(I2C3_ER_IRQn);
+ rccDisableI2C3(FALSE);
+ }
+#endif
+ }
+}
+
+/**
+ * @brief Receives data via the I2C bus as master.
+ * @details Number of receiving bytes must be more than 1 on STM32F1x. This is
+ * hardware restriction.
+ *
+ * @param[in] i2cp pointer to the @p I2CDriver object
+ * @param[in] addr slave device address
+ * @param[out] rxbuf pointer to the receive buffer
+ * @param[in] rxbytes number of bytes to be received
+ * @param[in] timeout the number of ticks before the operation timeouts,
+ * the following special values are allowed:
+ * - @a TIME_INFINITE no timeout.
+ * .
+ * @return The operation status.
+ * @retval MSG_OK if the function succeeded.
+ * @retval MSG_RESET if one or more I2C errors occurred, the errors can
+ * be retrieved using @p i2cGetErrors().
+ * @retval MSG_TIMEOUT if a timeout occurred before operation end. <b>After a
+ * timeout the driver must be stopped and restarted
+ * because the bus is in an uncertain state</b>.
+ *
+ * @notapi
+ */
+msg_t i2c_lld_master_receive_timeout(I2CDriver *i2cp, i2caddr_t addr,
+ uint8_t *rxbuf, size_t rxbytes,
+ systime_t timeout) {
+ I2C_TypeDef *dp = i2cp->i2c;
+ systime_t start, end;
+
+#if defined(STM32F1XX_I2C)
+ osalDbgCheck(rxbytes > 1);
+#endif
+
+ /* Resetting error flags for this transfer.*/
+ i2cp->errors = I2C_NO_ERROR;
+
+ /* Initializes driver fields, LSB = 1 -> receive.*/
+ i2cp->addr = (addr << 1) | 0x01;
+
+ /* Releases the lock from high level driver.*/
+ osalSysUnlock();
+
+ /* RX DMA setup.*/
+ dmaStreamSetMode(i2cp->dmarx, i2cp->rxdmamode);
+ dmaStreamSetMemory0(i2cp->dmarx, rxbuf);
+ dmaStreamSetTransactionSize(i2cp->dmarx, rxbytes);
+
+ /* Calculating the time window for the timeout on the busy bus condition.*/
+ start = osalOsGetSystemTimeX();
+ end = start + OSAL_MS2ST(STM32_I2C_BUSY_TIMEOUT);
+
+ /* Waits until BUSY flag is reset or, alternatively, for a timeout
+ condition.*/
+ while (true) {
+ osalSysLock();
+
+ /* If the bus is not busy then the operation can continue, note, the
+ loop is exited in the locked state.*/
+ if (!(dp->SR2 & I2C_SR2_BUSY) && !(dp->CR1 & I2C_CR1_STOP))
+ break;
+
+ /* If the system time went outside the allowed window then a timeout
+ condition is returned.*/
+ if (!osalOsIsTimeWithinX(osalOsGetSystemTimeX(), start, end))
+ return MSG_TIMEOUT;
+
+ osalSysUnlock();
+ }
+
+ /* Starts the operation.*/
+ dp->CR2 |= I2C_CR2_ITEVTEN;
+ dp->CR1 |= I2C_CR1_START | I2C_CR1_ACK;
+
+ /* Waits for the operation completion or a timeout.*/
+ return osalThreadSuspendTimeoutS(&i2cp->thread, timeout);
+}
+
+/**
+ * @brief Transmits data via the I2C bus as master.
+ * @details Number of receiving bytes must be 0 or more than 1 on STM32F1x.
+ * This is hardware restriction.
+ *
+ * @param[in] i2cp pointer to the @p I2CDriver object
+ * @param[in] addr slave device address
+ * @param[in] txbuf pointer to the transmit buffer
+ * @param[in] txbytes number of bytes to be transmitted
+ * @param[out] rxbuf pointer to the receive buffer
+ * @param[in] rxbytes number of bytes to be received
+ * @param[in] timeout the number of ticks before the operation timeouts,
+ * the following special values are allowed:
+ * - @a TIME_INFINITE no timeout.
+ * .
+ * @return The operation status.
+ * @retval MSG_OK if the function succeeded.
+ * @retval MSG_RESET if one or more I2C errors occurred, the errors can
+ * be retrieved using @p i2cGetErrors().
+ * @retval MSG_TIMEOUT if a timeout occurred before operation end. <b>After a
+ * timeout the driver must be stopped and restarted
+ * because the bus is in an uncertain state</b>.
+ *
+ * @notapi
+ */
+msg_t i2c_lld_master_transmit_timeout(I2CDriver *i2cp, i2caddr_t addr,
+ const uint8_t *txbuf, size_t txbytes,
+ uint8_t *rxbuf, size_t rxbytes,
+ systime_t timeout) {
+ I2C_TypeDef *dp = i2cp->i2c;
+ systime_t start, end;
+
+#if defined(STM32F1XX_I2C)
+ osalDbgCheck((rxbytes == 0) || ((rxbytes > 1) && (rxbuf != NULL)));
+#endif
+
+ /* Resetting error flags for this transfer.*/
+ i2cp->errors = I2C_NO_ERROR;
+
+ /* Initializes driver fields, LSB = 1 -> receive.*/
+ i2cp->addr = (addr << 1) | 0x01;
+
+ /* Releases the lock from high level driver.*/
+ osalSysUnlock();
+
+ /* TX DMA setup.*/
+ dmaStreamSetMode(i2cp->dmatx, i2cp->txdmamode);
+ dmaStreamSetMemory0(i2cp->dmatx, txbuf);
+ dmaStreamSetTransactionSize(i2cp->dmatx, txbytes);
+
+ /* RX DMA setup.*/
+ dmaStreamSetMode(i2cp->dmarx, i2cp->rxdmamode);
+ dmaStreamSetMemory0(i2cp->dmarx, rxbuf);
+ dmaStreamSetTransactionSize(i2cp->dmarx, rxbytes);
+
+ /* Calculating the time window for the timeout on the busy bus condition.*/
+ start = osalOsGetSystemTimeX();
+ end = start + OSAL_MS2ST(STM32_I2C_BUSY_TIMEOUT);
+
+ /* Waits until BUSY flag is reset or, alternatively, for a timeout
+ condition.*/
+ while (true) {
+ osalSysLock();
+
+ /* If the bus is not busy then the operation can continue, note, the
+ loop is exited in the locked state.*/
+ if (!(dp->SR2 & I2C_SR2_BUSY) && !(dp->CR1 & I2C_CR1_STOP))
+ break;
+
+ /* If the system time went outside the allowed window then a timeout
+ condition is returned.*/
+ if (!osalOsIsTimeWithinX(osalOsGetSystemTimeX(), start, end))
+ return MSG_TIMEOUT;
+
+ osalSysUnlock();
+ }
+
+ /* Starts the operation.*/
+ dp->CR2 |= I2C_CR2_ITEVTEN;
+ dp->CR1 |= I2C_CR1_START;
+
+ /* Waits for the operation completion or a timeout.*/
+ return osalThreadSuspendTimeoutS(&i2cp->thread, timeout);
+}
+
+#endif /* HAL_USE_I2C */
+
+/** @} */
diff --git a/os/hal/ports/STM32/LLD/I2Cv1/i2c_lld.h b/os/hal/ports/STM32/LLD/I2Cv1/i2c_lld.h
new file mode 100644
index 000000000..c36b4bcfe
--- /dev/null
+++ b/os/hal/ports/STM32/LLD/I2Cv1/i2c_lld.h
@@ -0,0 +1,512 @@
+/*
+ ChibiOS/RT - Copyright (C) 2006-2013 Giovanni Di Sirio
+
+ 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.
+*/
+/*
+ Concepts and parts of this file have been contributed by Uladzimir Pylinsky
+ aka barthess.
+ */
+
+/**
+ * @file STM32/I2Cv1/i2c_lld.h
+ * @brief STM32 I2C subsystem low level driver header.
+ *
+ * @addtogroup I2C
+ * @{
+ */
+
+#ifndef _I2C_LLD_H_
+#define _I2C_LLD_H_
+
+#if HAL_USE_I2C || defined(__DOXYGEN__)
+
+/*===========================================================================*/
+/* Driver constants. */
+/*===========================================================================*/
+
+/**
+ * @brief Peripheral clock frequency.
+ */
+#define I2C_CLK_FREQ ((STM32_PCLK1) / 1000000)
+
+/*===========================================================================*/
+/* Driver pre-compile time settings. */
+/*===========================================================================*/
+
+/**
+ * @name Configuration options
+ * @{
+ */
+/**
+ * @brief I2C1 driver enable switch.
+ * @details If set to @p TRUE the support for I2C1 is included.
+ * @note The default is @p FALSE.
+ */
+#if !defined(STM32_I2C_USE_I2C1) || defined(__DOXYGEN__)
+#define STM32_I2C_USE_I2C1 FALSE
+#endif
+
+/**
+ * @brief I2C2 driver enable switch.
+ * @details If set to @p TRUE the support for I2C2 is included.
+ * @note The default is @p FALSE.
+ */
+#if !defined(STM32_I2C_USE_I2C2) || defined(__DOXYGEN__)
+#define STM32_I2C_USE_I2C2 FALSE
+#endif
+
+/**
+ * @brief I2C3 driver enable switch.
+ * @details If set to @p TRUE the support for I2C3 is included.
+ * @note The default is @p FALSE.
+ */
+#if !defined(STM32_I2C_USE_I2C3) || defined(__DOXYGEN__)
+#define STM32_I2C_USE_I2C3 FALSE
+#endif
+
+/**
+ * @brief I2C timeout on busy condition in milliseconds.
+ */
+#if !defined(STM32_I2C_BUSY_TIMEOUT) || defined(__DOXYGEN__)
+#define STM32_I2C_BUSY_TIMEOUT 50
+#endif
+
+/**
+ * @brief I2C1 interrupt priority level setting.
+ */
+#if !defined(STM32_I2C_I2C1_IRQ_PRIORITY) || defined(__DOXYGEN__)
+#define STM32_I2C_I2C1_IRQ_PRIORITY 10
+#endif
+
+/**
+ * @brief I2C2 interrupt priority level setting.
+ */
+#if !defined(STM32_I2C_I2C2_IRQ_PRIORITY) || defined(__DOXYGEN__)
+#define STM32_I2C_I2C2_IRQ_PRIORITY 10
+#endif
+
+/**
+ * @brief I2C3 interrupt priority level setting.
+ */
+#if !defined(STM32_I2C_I2C3_IRQ_PRIORITY) || defined(__DOXYGEN__)
+#define STM32_I2C_I2C3_IRQ_PRIORITY 10
+#endif
+
+/**
+* @brief I2C1 DMA priority (0..3|lowest..highest).
+* @note The priority level is used for both the TX and RX DMA streams but
+* because of the streams ordering the RX stream has always priority
+* over the TX stream.
+*/
+#if !defined(STM32_I2C_I2C1_DMA_PRIORITY) || defined(__DOXYGEN__)
+#define STM32_I2C_I2C1_DMA_PRIORITY 1
+#endif
+
+/**
+* @brief I2C2 DMA priority (0..3|lowest..highest).
+* @note The priority level is used for both the TX and RX DMA streams but
+* because of the streams ordering the RX stream has always priority
+* over the TX stream.
+*/
+#if !defined(STM32_I2C_I2C2_DMA_PRIORITY) || defined(__DOXYGEN__)
+#define STM32_I2C_I2C2_DMA_PRIORITY 1
+#endif
+
+/**
+* @brief I2C3 DMA priority (0..3|lowest..highest).
+* @note The priority level is used for both the TX and RX DMA streams but
+* because of the streams ordering the RX stream has always priority
+* over the TX stream.
+*/
+#if !defined(STM32_I2C_I2C3_DMA_PRIORITY) || defined(__DOXYGEN__)
+#define STM32_I2C_I2C3_DMA_PRIORITY 1
+#endif
+
+/**
+ * @brief I2C DMA error hook.
+ * @note The default action for DMA errors is a system halt because DMA
+ * error can only happen because programming errors.
+ */
+#if !defined(STM32_I2C_DMA_ERROR_HOOK) || defined(__DOXYGEN__)
+#define STM32_I2C_DMA_ERROR_HOOK(i2cp) chSysHalt("DMA failure")
+#endif
+
+#if STM32_ADVANCED_DMA || defined(__DOXYGEN__)
+
+/**
+ * @brief DMA stream used for I2C1 RX operations.
+ * @note This option is only available on platforms with enhanced DMA.
+ */
+#if !defined(STM32_I2C_I2C1_RX_DMA_STREAM) || defined(__DOXYGEN__)
+#define STM32_I2C_I2C1_RX_DMA_STREAM STM32_DMA_STREAM_ID(1, 0)
+#endif
+
+/**
+ * @brief DMA stream used for I2C1 TX operations.
+ * @note This option is only available on platforms with enhanced DMA.
+ */
+#if !defined(STM32_I2C_I2C1_TX_DMA_STREAM) || defined(__DOXYGEN__)
+#define STM32_I2C_I2C1_TX_DMA_STREAM STM32_DMA_STREAM_ID(1, 6)
+#endif
+
+/**
+ * @brief DMA stream used for I2C2 RX operations.
+ * @note This option is only available on platforms with enhanced DMA.
+ */
+#if !defined(STM32_I2C_I2C2_RX_DMA_STREAM) || defined(__DOXYGEN__)
+#define STM32_I2C_I2C2_RX_DMA_STREAM STM32_DMA_STREAM_ID(1, 2)
+#endif
+
+/**
+ * @brief DMA stream used for I2C2 TX operations.
+ * @note This option is only available on platforms with enhanced DMA.
+ */
+#if !defined(STM32_I2C_I2C2_TX_DMA_STREAM) || defined(__DOXYGEN__)
+#define STM32_I2C_I2C2_TX_DMA_STREAM STM32_DMA_STREAM_ID(1, 7)
+#endif
+
+/**
+ * @brief DMA stream used for I2C3 RX operations.
+ * @note This option is only available on platforms with enhanced DMA.
+ */
+#if !defined(STM32_I2C_I2C3_RX_DMA_STREAM) || defined(__DOXYGEN__)
+#define STM32_I2C_I2C3_RX_DMA_STREAM STM32_DMA_STREAM_ID(1, 2)
+#endif
+
+/**
+ * @brief DMA stream used for I2C3 TX operations.
+ * @note This option is only available on platforms with enhanced DMA.
+ */
+#if !defined(STM32_I2C_I2C3_TX_DMA_STREAM) || defined(__DOXYGEN__)
+#define STM32_I2C_I2C3_TX_DMA_STREAM STM32_DMA_STREAM_ID(1, 4)
+#endif
+
+#else /* !STM32_ADVANCED_DMA */
+
+/* Fixed streams for platforms using the old DMA peripheral, the values are
+ valid for both STM32F1xx and STM32L1xx.*/
+#define STM32_I2C_I2C1_RX_DMA_STREAM STM32_DMA_STREAM_ID(1, 7)
+#define STM32_I2C_I2C1_TX_DMA_STREAM STM32_DMA_STREAM_ID(1, 6)
+#define STM32_I2C_I2C2_RX_DMA_STREAM STM32_DMA_STREAM_ID(1, 5)
+#define STM32_I2C_I2C2_TX_DMA_STREAM STM32_DMA_STREAM_ID(1, 4)
+
+#endif /* !STM32_ADVANCED_DMA*/
+
+/* Flag for the whole STM32F1XX family. */
+#if defined(STM32F10X_LD_VL) || defined(STM32F10X_MD_VL) || \
+ defined(STM32F10X_HD_VL) || defined(STM32F10X_LD) || \
+ defined(STM32F10X_MD) || defined(STM32F10X_HD) || \
+ defined(STM32F10X_XL) || defined(STM32F10X_CL)
+#define STM32F1XX_I2C
+#endif
+/** @} */
+
+/*===========================================================================*/
+/* Derived constants and error checks. */
+/*===========================================================================*/
+
+/** @brief error checks */
+#if STM32_I2C_USE_I2C1 && !STM32_HAS_I2C1
+#error "I2C1 not present in the selected device"
+#endif
+
+#if STM32_I2C_USE_I2C2 && !STM32_HAS_I2C2
+#error "I2C2 not present in the selected device"
+#endif
+
+#if STM32_I2C_USE_I2C3 && !STM32_HAS_I2C3
+#error "I2C3 not present in the selected device"
+#endif
+
+#if !STM32_I2C_USE_I2C1 && !STM32_I2C_USE_I2C2 && \
+ !STM32_I2C_USE_I2C3
+#error "I2C driver activated but no I2C peripheral assigned"
+#endif
+
+#if STM32_I2C_USE_I2C1 && \
+ !CORTEX_IS_VALID_KERNEL_PRIORITY(STM32_I2C_I2C1_IRQ_PRIORITY)
+#error "Invalid IRQ priority assigned to I2C1"
+#endif
+
+#if STM32_I2C_USE_I2C2 && \
+ !CORTEX_IS_VALID_KERNEL_PRIORITY(STM32_I2C_I2C2_IRQ_PRIORITY)
+#error "Invalid IRQ priority assigned to I2C2"
+#endif
+
+#if STM32_I2C_USE_I2C3 && \
+ !CORTEX_IS_VALID_KERNEL_PRIORITY(STM32_I2C_I2C3_IRQ_PRIORITY)
+#error "Invalid IRQ priority assigned to I2C3"
+#endif
+
+#if STM32_I2C_USE_I2C1 && \
+ !STM32_DMA_IS_VALID_PRIORITY(STM32_I2C_I2C1_DMA_PRIORITY)
+#error "Invalid DMA priority assigned to I2C1"
+#endif
+
+#if STM32_I2C_USE_I2C2 && \
+ !STM32_DMA_IS_VALID_PRIORITY(STM32_I2C_I2C2_DMA_PRIORITY)
+#error "Invalid DMA priority assigned to I2C2"
+#endif
+
+#if STM32_I2C_USE_I2C3 && \
+ !STM32_DMA_IS_VALID_PRIORITY(STM32_I2C_I2C3_DMA_PRIORITY)
+#error "Invalid DMA priority assigned to I2C3"
+#endif
+
+/* The following checks are only required when there is a DMA able to
+ reassign streams to different channels.*/
+#if STM32_ADVANCED_DMA
+/* Check on the presence of the DMA streams settings in mcuconf.h.*/
+#if STM32_I2C_USE_I2C1 && (!defined(STM32_I2C_I2C1_RX_DMA_STREAM) || \
+ !defined(STM32_I2C_I2C1_TX_DMA_STREAM))
+#error "I2C1 DMA streams not defined"
+#endif
+
+#if STM32_I2C_USE_I2C2 && (!defined(STM32_I2C_I2C2_RX_DMA_STREAM) || \
+ !defined(STM32_I2C_I2C2_TX_DMA_STREAM))
+#error "I2C2 DMA streams not defined"
+#endif
+
+/* Check on the validity of the assigned DMA channels.*/
+#if STM32_I2C_USE_I2C1 && \
+ !STM32_DMA_IS_VALID_ID(STM32_I2C_I2C1_RX_DMA_STREAM, \
+ STM32_I2C1_RX_DMA_MSK)
+#error "invalid DMA stream associated to I2C1 RX"
+#endif
+
+#if STM32_I2C_USE_I2C1 && \
+ !STM32_DMA_IS_VALID_ID(STM32_I2C_I2C1_TX_DMA_STREAM, \
+ STM32_I2C1_TX_DMA_MSK)
+#error "invalid DMA stream associated to I2C1 TX"
+#endif
+
+#if STM32_I2C_USE_I2C2 && \
+ !STM32_DMA_IS_VALID_ID(STM32_I2C_I2C2_RX_DMA_STREAM, \
+ STM32_I2C2_RX_DMA_MSK)
+#error "invalid DMA stream associated to I2C2 RX"
+#endif
+
+#if STM32_I2C_USE_I2C2 && \
+ !STM32_DMA_IS_VALID_ID(STM32_I2C_I2C2_TX_DMA_STREAM, \
+ STM32_I2C2_TX_DMA_MSK)
+#error "invalid DMA stream associated to I2C2 TX"
+#endif
+
+#if STM32_I2C_USE_I2C3 && \
+ !STM32_DMA_IS_VALID_ID(STM32_I2C_I2C3_RX_DMA_STREAM, \
+ STM32_I2C3_RX_DMA_MSK)
+#error "invalid DMA stream associated to I2C3 RX"
+#endif
+
+#if STM32_I2C_USE_I2C3 && \
+ !STM32_DMA_IS_VALID_ID(STM32_I2C_I2C3_TX_DMA_STREAM, \
+ STM32_I2C3_TX_DMA_MSK)
+#error "invalid DMA stream associated to I2C3 TX"
+#endif
+#endif /* STM32_ADVANCED_DMA */
+
+#if !defined(STM32_DMA_REQUIRED)
+#define STM32_DMA_REQUIRED
+#endif
+
+/* Check clock range. */
+#if defined(STM32F4XX)
+#if !(I2C_CLK_FREQ >= 2) && (I2C_CLK_FREQ <= 42)
+#error "I2C peripheral clock frequency out of range."
+#endif
+
+#elif defined(STM32L1XX_MD)
+#if !(I2C_CLK_FREQ >= 2) && (I2C_CLK_FREQ <= 32)
+#error "I2C peripheral clock frequency out of range."
+#endif
+
+#elif defined(STM32F2XX)
+#if !(I2C_CLK_FREQ >= 2) && (I2C_CLK_FREQ <= 30)
+#error "I2C peripheral clock frequency out of range."
+#endif
+
+#elif defined(STM32F10X_LD_VL) || defined(STM32F10X_MD_VL) || \
+ defined(STM32F10X_HD_VL)
+#if !(I2C_CLK_FREQ >= 2) && (I2C_CLK_FREQ <= 24)
+#error "I2C peripheral clock frequency out of range."
+#endif
+
+#elif defined(STM32F10X_LD) || defined(STM32F10X_MD) || \
+ defined(STM32F10X_HD) || defined(STM32F10X_XL) || \
+ defined(STM32F10X_CL)
+#if !(I2C_CLK_FREQ >= 2) && (I2C_CLK_FREQ <= 36)
+#error "I2C peripheral clock frequency out of range."
+#endif
+#else
+#error "unspecified, unsupported or invalid STM32 platform"
+#endif
+
+/*===========================================================================*/
+/* Driver data structures and types. */
+/*===========================================================================*/
+
+/**
+ * @brief Type representing I2C address.
+ */
+typedef uint16_t i2caddr_t;
+
+/**
+ * @brief I2C Driver condition flags type.
+ */
+typedef uint32_t i2cflags_t;
+
+/**
+ * @brief Supported modes for the I2C bus.
+ */
+typedef enum {
+ OPMODE_I2C = 1,
+ OPMODE_SMBUS_DEVICE = 2,
+ OPMODE_SMBUS_HOST = 3,
+} i2copmode_t;
+
+/**
+ * @brief Supported duty cycle modes for the I2C bus.
+ */
+typedef enum {
+ STD_DUTY_CYCLE = 1,
+ FAST_DUTY_CYCLE_2 = 2,
+ FAST_DUTY_CYCLE_16_9 = 3,
+} i2cdutycycle_t;
+
+/**
+ * @brief Driver configuration structure.
+ */
+typedef struct {
+ i2copmode_t op_mode; /**< @brief Specifies the I2C mode. */
+ uint32_t clock_speed; /**< @brief Specifies the clock frequency.
+ @note Must be set to a value lower
+ than 400kHz. */
+ i2cdutycycle_t duty_cycle; /**< @brief Specifies the I2C fast mode
+ duty cycle. */
+} I2CConfig;
+
+/**
+ * @brief Type of a structure representing an I2C driver.
+ */
+typedef struct I2CDriver I2CDriver;
+
+/**
+ * @brief Structure representing an I2C driver.
+ */
+struct I2CDriver {
+ /**
+ * @brief Driver state.
+ */
+ i2cstate_t state;
+ /**
+ * @brief Current configuration data.
+ */
+ const I2CConfig *config;
+ /**
+ * @brief Error flags.
+ */
+ i2cflags_t errors;
+#if I2C_USE_MUTUAL_EXCLUSION || defined(__DOXYGEN__)
+ /**
+ * @brief Mutex protecting the bus.
+ */
+ mutex_t mutex;
+#endif /* I2C_USE_MUTUAL_EXCLUSION */
+#if defined(I2C_DRIVER_EXT_FIELDS)
+ I2C_DRIVER_EXT_FIELDS
+#endif
+ /* End of the mandatory fields.*/
+ /**
+ * @brief Thread waiting for I/O completion.
+ */
+ thread_reference_t thread;
+ /**
+ * @brief Current slave address without R/W bit.
+ */
+ i2caddr_t addr;
+ /**
+ * @brief RX DMA mode bit mask.
+ */
+ uint32_t rxdmamode;
+ /**
+ * @brief TX DMA mode bit mask.
+ */
+ uint32_t txdmamode;
+ /**
+ * @brief Receive DMA channel.
+ */
+ const stm32_dma_stream_t *dmarx;
+ /**
+ * @brief Transmit DMA channel.
+ */
+ const stm32_dma_stream_t *dmatx;
+ /**
+ * @brief Pointer to the I2Cx registers block.
+ */
+ I2C_TypeDef *i2c;
+};
+
+/*===========================================================================*/
+/* Driver macros. */
+/*===========================================================================*/
+
+/**
+ * @brief Get errors from I2C driver.
+ *
+ * @param[in] i2cp pointer to the @p I2CDriver object
+ *
+ * @notapi
+ */
+#define i2c_lld_get_errors(i2cp) ((i2cp)->errors)
+
+/*===========================================================================*/
+/* External declarations. */
+/*===========================================================================*/
+
+#if !defined(__DOXYGEN__)
+#if STM32_I2C_USE_I2C1
+extern I2CDriver I2CD1;
+#endif
+
+#if STM32_I2C_USE_I2C2
+extern I2CDriver I2CD2;
+#endif
+
+#if STM32_I2C_USE_I2C3
+extern I2CDriver I2CD3;
+#endif
+#endif /* !defined(__DOXYGEN__) */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+ void i2c_lld_init(void);
+ void i2c_lld_start(I2CDriver *i2cp);
+ void i2c_lld_stop(I2CDriver *i2cp);
+ msg_t i2c_lld_master_transmit_timeout(I2CDriver *i2cp, i2caddr_t addr,
+ const uint8_t *txbuf, size_t txbytes,
+ uint8_t *rxbuf, size_t rxbytes,
+ systime_t timeout);
+ msg_t i2c_lld_master_receive_timeout(I2CDriver *i2cp, i2caddr_t addr,
+ uint8_t *rxbuf, size_t rxbytes,
+ systime_t timeout);
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* HAL_USE_I2C */
+
+#endif /* _I2C_LLD_H_ */
+
+/** @} */