i2c: Various fixes, extensions, documentation.

-Fix clock calculations for fast-mode support
-Add I2C_REMAP option to remap i2c1 (untested)
-Add I2C_BUS_RESET option to reset bus on initialization
-Add optional timeout parameter
-Doxygen comments
-Various cleanup

10-bit slave addressing is untested until I have a device that speaks
such.

1 files changed, 14 insertions, 0 deletions

diff --git a/libmaple/gpio.c b/libmaple/gpio.c
index 5484e21..c250f68 100644
--- a/libmaple/gpio.c
+++ b/libmaple/gpio.c
@@ -174,3 +174,17 @@ void afio_exti_select(afio_exti_num exti, afio_exti_port gpio_port) {
     cr |= gpio_port << shift;
     *exti_cr = cr;
 }
+
+/**
+ * @brief Remap an alternate function peripheral to a different pin
+ * mapping
+ * @param peripheral to remap
+ */
+void afio_remap(AFIORemapPeripheral p) {
+    if (p & AFIO_REMAP_USE_MAPR2) {
+        p &= ~AFIO_REMAP_USE_MAPR2;
+        AFIO_BASE->MAPR2 |= p;
+    } else {
+        AFIO_BASE->MAPR |= p;
+    }
+}