STM32F0 I2C: Initial cut at driver. Still a work in progress.

arch/arm/src/stm32f0/Make.defs

@@ -95,6 +95,10 @@ ifeq ($(CONFIG_STM32F0_USB),y)
 CHIP_CSRCS += stm32f0_usbdev.c
 endif
 
+ifeq ($(CONFIG_STM32F0_I2C),y)
+CHIP_CSRCS += stm32f0_i2c.c
+endif
+
 ifeq ($(CONFIG_STM32F0_SPI0),y)
 CHIP_CSRCS += stm32f0_spi.c
 else

arch/arm/src/stm32f0/stm32f0_i2c.h

@@ -0,0 +1,104 @@
+/****************************************************************************
+ * arch/arm/src/stm32f0/stm32f0_i2c.h
+ *
+ *   Copyright (C) 2009, 2011, 2013 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. 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.
+ * 3. Neither the name NuttX 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 OWNER 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.
+ *
+ ****************************************************************************/
+
+#ifndef __ARCH_ARM_SRC_STM32F0_STM32F0_I2C_H
+#define __ARCH_ARM_SRC_STM32F0_STM32F0_I2C_H
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+#include <nuttx/i2c/i2c_master.h>
+
+#include "chip.h"
+#include "chip/stm32f0_i2c.h"
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/* If a dynamic timeout is selected, then a non-negative, non-zero micro-
+ * seconds per byte value must be provided as well.
+ */
+
+#ifdef CONFIG_STM32F0_I2C_DYNTIMEO
+#  if CONFIG_STM32F0_I2C_DYNTIMEO_USECPERBYTE < 1
+#    warning "Ignoring CONFIG_STM32F0_I2C_DYNTIMEO because of CONFIG_STM32F0_I2C_DYNTIMEO_USECPERBYTE"
+#    undef CONFIG_STM32F0_I2C_DYNTIMEO
+#  endif
+#endif
+
+/****************************************************************************
+ * Public Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: stm32f0_i2cbus_initialize
+ *
+ * Description:
+ *   Initialize the selected I2C port. And return a unique instance of struct
+ *   struct i2c_master_s.  This function may be called to obtain multiple
+ *   instances of the interface, each of which may be set up with a
+ *   different frequency and slave address.
+ *
+ * Input Parameter:
+ *   Port number (for hardware that has multiple I2C interfaces)
+ *
+ * Returned Value:
+ *   Valid I2C device structure reference on succcess; a NULL on failure
+ *
+ ****************************************************************************/
+
+FAR struct i2c_master_s *stm32f0_i2cbus_initialize(int port);
+
+/****************************************************************************
+ * Name: stm32f0_i2cbus_uninitialize
+ *
+ * Description:
+ *   De-initialize the selected I2C port, and power down the device.
+ *
+ * Input Parameter:
+ *   Device structure as returned by the stm32f0_i2cbus_initialize()
+ *
+ * Returned Value:
+ *   OK on success, ERROR when internal reference count mismatch or dev
+ *   points to invalid hardware device.
+ *
+ ****************************************************************************/
+
+int stm32f0_i2cbus_uninitialize(FAR struct i2c_master_s *dev);
+
+#endif /* __ARCH_ARM_SRC_STM32F0_STM32F0_I2C_H */

configs/stm32f0discovery/include/board.h

@@ -239,4 +239,9 @@
 #define GPIO_USART1_TX           GPIO_USART1_TX_1
 #define GPIO_USART1_RX           GPIO_USART1_RX_1
 
+/* I2C pins definition */
+
+#define GPIO_I2C1_SCL            GPIO_I2C1_SCL_1
+#define GPIO_I2C1_SDA            GPIO_I2C1_SDA_1
+
 #endif  /* __CONFIG_STM32F0DISCOVERY_INCLUDE_BOARD_H */