I2C: Restore on F1, refactoring prep for F2.

Bring back <libmaple/i2c.h> support on STM32F1 with a view towards how
it'll be implemented on STM32F2. There are still many F1-isms in
libmaple/i2c.c and <libmaple/i2c.h>, to be dealt with subsequently.

Move device declarations and base pointer definitions to a new F1
<series/i2c.h>. The register maps and bit definitions themselves are
identical on both series, so leave them in the libmaple header.

Add i2c_private.h, which contains:

- I2C_DEV(), a convenience macro for defining an i2c_dev, and
- declarations for the event and error IRQ handlers.

The IRQ handlers are large, and I2C is slow anyway, so I see no reason
to make them inline in the private header (as we do for some other
peripherals). We just expose the existing ones that were formerly
static in libmaple/i2c.c, but prefix the names with underscore.

Move the device declarations and IRQ handlers into new
stm32f1/i2c.c. These use the i2c_private.h API.

Signed-off-by: Marti Bolivar <mbolivar@leaflabs.com>

libmaple/i2c.c

@@ -2,6 +2,7 @@
  * The MIT License
  *
  * Copyright (c) 2010 Perry Hung.
+ * Copyright (c) 2012 LeafLabs, LLC.
  *
  * Permission is hereby granted, free of charge, to any person
  * obtaining a copy of this software and associated documentation
@@ -40,32 +41,6 @@
 
 #include <string.h>
 
-static i2c_dev i2c_dev1 = {
-    .regs         = I2C1_BASE,
-    .gpio_port    = &gpiob,
-    .sda_pin      = 7,
-    .scl_pin      = 6,
-    .clk_id       = RCC_I2C1,
-    .ev_nvic_line = NVIC_I2C1_EV,
-    .er_nvic_line = NVIC_I2C1_ER,
-    .state        = I2C_STATE_DISABLED
-};
-/** I2C1 device */
-i2c_dev* const I2C1 = &i2c_dev1;
-
-static i2c_dev i2c_dev2 = {
-    .regs         = I2C2_BASE,
-    .gpio_port    = &gpiob,
-    .sda_pin      = 11,
-    .scl_pin      = 10,
-    .clk_id       = RCC_I2C2,
-    .ev_nvic_line = NVIC_I2C2_EV,
-    .er_nvic_line = NVIC_I2C2_ER,
-    .state        = I2C_STATE_DISABLED
-};
-/** I2C2 device */
-i2c_dev* const I2C2 = &i2c_dev2;
-
 static inline int32 wait_for_state_change(i2c_dev *dev,
                                           i2c_state state,
                                           uint32 timeout);
@@ -129,7 +104,7 @@ enum {
  * @brief IRQ handler for I2C master. Handles transmission/reception.
  * @param dev I2C device
  */
-static void i2c_irq_handler(i2c_dev *dev) {
+void _i2c_irq_handler(i2c_dev *dev) {
     i2c_msg *msg = dev->msg;
 
     uint8 read = msg->flags & I2C_MSG_READ;
@@ -289,20 +264,12 @@ static void i2c_irq_handler(i2c_dev *dev) {
     }
 }
 
-void __irq_i2c1_ev(void) {
-   i2c_irq_handler(&i2c_dev1);
-}
-
-void __irq_i2c2_ev(void) {
-   i2c_irq_handler(&i2c_dev2);
-}
-
 /**
  * @brief Interrupt handler for I2C error conditions
  * @param dev I2C device
  * @sideeffect Aborts any pending I2C transactions
  */
-static void i2c_irq_error_handler(i2c_dev *dev) {
+void _i2c_irq_error_handler(i2c_dev *dev) {
     I2C_CRUMB(ERROR_ENTRY, dev->regs->SR1, dev->regs->SR2);
 
     dev->error_flags = dev->regs->SR2 & (I2C_SR1_BERR |
@@ -318,14 +285,6 @@ static void i2c_irq_error_handler(i2c_dev *dev) {
     dev->state = I2C_STATE_ERROR;
 }
 
-void __irq_i2c1_er(void) {
-    i2c_irq_error_handler(&i2c_dev1);
-}
-
-void __irq_i2c2_er(void) {
-    i2c_irq_error_handler(&i2c_dev2);
-}
-
 /**
  * @brief Reset an I2C bus.
  *

libmaple/i2c_private.h

@@ -0,0 +1,46 @@
+/******************************************************************************
+ * The MIT License
+ *
+ * Copyright (c) 2012 LeafLabs, LLC.
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy,
+ * modify, merge, publish, distribute, sublicense, and/or sell copies
+ * of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *****************************************************************************/
+
+#ifndef _LIBMAPLE_I2C_PRIVATE_H_
+#define _LIBMAPLE_I2C_PRIVATE_H_
+
+#define I2C_DEV(num, port, sda, scl)              \
+    {                                             \
+        .regs         = I2C##num##_BASE,          \
+        .gpio_port    = port,                     \
+        .sda_pin      = sda,                      \
+        .scl_pin      = scl,                      \
+        .clk_id       = RCC_I2C##num,             \
+        .ev_nvic_line = NVIC_I2C##num##_EV,       \
+        .er_nvic_line = NVIC_I2C##num##_ER,       \
+        .state        = I2C_STATE_DISABLED,       \
+    }
+
+struct i2c_dev;
+void _i2c_irq_handler(struct i2c_dev *dev);
+void _i2c_irq_error_handler(struct i2c_dev *dev);
+
+#endif  /* _LIBMAPLE_I2C_PRIVATE_H_ */

libmaple/include/libmaple/i2c.h

@@ -37,6 +37,7 @@
 extern "C" {
 #endif
 
+#include <series/i2c.h>
 #include <libmaple/libmaple_types.h>
 #include <libmaple/rcc.h>
 #include <libmaple/nvic.h>
@@ -96,22 +97,6 @@ typedef struct i2c_dev {
     volatile i2c_state state;   /**< Device state */
 } i2c_dev;
 
-/*
- * Devices
- */
-
-extern i2c_dev* const I2C1;
-extern i2c_dev* const I2C2;
-
-/*
- * Register map base pointers
- */
-
-/** I2C1 register map base pointer */
-#define I2C1_BASE               ((struct i2c_reg_map*)0x40005400)
-/** I2C2 register map base pointer */
-#define I2C2_BASE               ((struct i2c_reg_map*)0x40005800)
-
 /*
  * Register bit definitions
  */

libmaple/rules.mk

@@ -27,10 +27,11 @@ cSRCS_$(d) += timer.c
 cSRCS_$(d) += usart.c
 cSRCS_$(d) += usart_private.c
 cSRCS_$(d) += util.c
-# These still need to be brought back for F1:
-# cSRCS_$(d) += i2c.c
-
 sSRCS_$(d) := exc.S
+# I2C support must be ported to F2:
+ifeq ($(MCU_SERIES),stm32f1)
+cSRCS_$(d) += i2c.c
+endif
 
 cFILES_$(d) := $(cSRCS_$(d):%=$(d)/%)
 sFILES_$(d) := $(sSRCS_$(d):%=$(d)/%)

libmaple/stm32f1/i2c.c

@@ -0,0 +1,60 @@
+/******************************************************************************
+ * The MIT License
+ *
+ * Copyright (c) 2012 LeafLabs, LLC.
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy,
+ * modify, merge, publish, distribute, sublicense, and/or sell copies
+ * of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *****************************************************************************/
+
+#include "i2c_private.h"
+#include <libmaple/i2c.h>
+
+/*
+ * Devices
+ */
+
+static i2c_dev i2c1 = I2C_DEV(1, &gpiob, 7, 6);
+static i2c_dev i2c2 = I2C_DEV(2, &gpiob, 11, 10);
+
+/** STM32F1 I2C device 1 */
+i2c_dev* const I2C1 = &i2c1;
+/** STM32F1 I2C device 2 */
+i2c_dev* const I2C2 = &i2c2;
+
+/*
+ * IRQ handlers
+ */
+
+void __irq_i2c1_ev(void) {
+   _i2c_irq_handler(I2C1);
+}
+
+void __irq_i2c2_ev(void) {
+   _i2c_irq_handler(I2C2);
+}
+
+void __irq_i2c1_er(void) {
+    _i2c_irq_error_handler(I2C1);
+}
+
+void __irq_i2c2_er(void) {
+    _i2c_irq_error_handler(I2C2);
+}

libmaple/stm32f1/include/series/i2c.h

@@ -0,0 +1,56 @@
+/******************************************************************************
+ * The MIT License
+ *
+ * Copyright (c) 2010 Perry Hung (from <libmaple/i2c.h>).
+ * Copyright (c) 2012 LeafLabs, LLC.
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy,
+ * modify, merge, publish, distribute, sublicense, and/or sell copies
+ * of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *****************************************************************************/
+
+/**
+ * @file libmaple/include/stm32f1/include/series/i2c.h
+ * @brief STM32F1 I2C
+ */
+
+#ifndef _LIBMAPLE_STM32F1_I2C_H_
+#define _LIBMAPLE_STM32F1_I2C_H_
+
+/*
+ * Register maps
+ */
+
+struct i2c_reg_map;
+
+/** STM32F1 I2C1 register map base pointer */
+#define I2C1_BASE               ((struct i2c_reg_map*)0x40005400)
+/** STM32F1 I2C2 register map base pointer */
+#define I2C2_BASE               ((struct i2c_reg_map*)0x40005800)
+
+/*
+ * Devices
+ */
+
+struct i2c_dev;
+
+extern struct i2c_dev* const I2C1;
+extern struct i2c_dev* const I2C2;
+
+#endif  /* _LIBMAPLE_STM32F1_I2C_H_ */

libmaple/stm32f1/rules.mk

@@ -20,6 +20,7 @@ cSRCS_$(d) += dma.c
 cSRCS_$(d) += exti.c
 cSRCS_$(d) += fsmc.c
 cSRCS_$(d) += gpio.c
+cSRCS_$(d) += i2c.c
 cSRCS_$(d) += rcc.c
 cSRCS_$(d) += spi.c
 cSRCS_$(d) += timer.c