14 files changed, 262 insertions, 68 deletions

diff --git a/lib/pbdrv/drv/arduino/index.dox b/lib/pbdrv/drv/arduino/index.dox
new file mode 100644
index 0000000..4c74222
--- /dev/null
+++ b/lib/pbdrv/drv/arduino/index.dox
@@ -0,0 +1,19 @@
+// vim:ft=doxygen
+/**
+\ingroup pb_drv
+\defgroup pb_drv_arduino Arduino
+\brief Arduino (Arduino-CMake-Toolchain) driver
+
+This driver is automatically enabled if the variable \c ARDUINO is defined in
+your CMakeLists.txt (it is by default when using Arduino-CMake-Toolchain).
+
+\note This driver automatically includes the
+\ref pb_ext_freertos "FreeRTOS extension" for deferring calls to \c
+pb_i2c_recv() from the I2C ISR.
+
+This driver is known to work with the following MCUs:
+- ATmega328P (Arduino Uno)
+- ATmega2560 (Arduino Mega)
+
+*/
+
diff --git a/lib/pbdrv/drv/arduino/mod.cpp b/lib/pbdrv/drv/arduino/mod.cpp
index 9130334..2eef8d5 100644
--- a/lib/pbdrv/drv/arduino/mod.cpp
+++ b/lib/pbdrv/drv/arduino/mod.cpp
@@ -42,6 +42,7 @@ static void pb_setup() {
 	Wire.onReceive(recv_event);
 }
 
+/// \ingroup pb_drv_arduino
 __weak void pb_i2c_send(i2c_addr_t addr, const uint8_t * buf, size_t sz) {
 	Wire.beginTransmission((int) addr);
 	Wire.write(buf, sz);
@@ -64,7 +65,16 @@ void loop_task() {
 	}
 }
 
-//! Application entrypoint
+/**
+ * \ingroup pb_drv_arduino
+ * \brief Application entrypoint
+ *
+ * \note I should really be able to use Arduino's initVariant function for
+ * this, but I can't seem to get it to link properly using the CMake setup in
+ * this repository. Overriding the main() function seems to work, and the
+ * USBCON thing in the default Arduino main() function isn't needed because
+ * puzzle modules are likely not using USB.
+ */
 int main(void) {
 	init(); // call arduino internal setup
 	setup(); // call regular arduino setup
@@ -74,11 +84,3 @@ int main(void) {
 	return 0;
 }
 
-/**
- * \note I should really be able to use Arduino's initVariant function for
- * this, but I can't seem to get it to link properly using the CMake setup in
- * this repository. Overriding the main() function seems to work, and the
- * USBCON thing in the default Arduino main() function isn't needed because
- * puzzle modules are likely not using USB.
- */
-
diff --git a/lib/pbdrv/drv/index.dox b/lib/pbdrv/drv/index.dox
new file mode 100644
index 0000000..1fe09e2
--- /dev/null
+++ b/lib/pbdrv/drv/index.dox
@@ -0,0 +1,32 @@
+// vim:ft=doxygen
+/**
+\ingroup pbdrv-mod
+\defgroup pb_drv Drivers
+\brief Platform-specific \ref pbdrv-mod implementations
+
+Like \ref pb_ext "extensions", drivers provide platform-specific
+implementations for various functions used in \ref pbdrv-mod.
+
+Drivers are automatically included based on your build configuration, and you
+only need to ensure \c pbdrv-mod is linked with your final executable in order
+to use one of the available drivers:
+
+```cmake
+# include pbdrv
+add_subdirectory(lib/pbdrv)
+
+# link pbdrv-mod
+target_link_libraries(main pbdrv-mod)
+
+```
+
+If there is no existing driver for your target, you may implement the following
+in order to use \ref pbdrv-mod:
+
+- The \c pb_i2c_recv() function must be **called** for every received I2C
+	message
+- The \c pb_i2c_send() function must be **implemented** using the
+	platform/device-specific I2C write function
+
+*/
+
diff --git a/lib/pbdrv/ext/freertos/index.dox b/lib/pbdrv/ext/freertos/index.dox
new file mode 100644
index 0000000..dfa45ff
--- /dev/null
+++ b/lib/pbdrv/ext/freertos/index.dox
@@ -0,0 +1,6 @@
+// vim:ft=doxygen
+/**
+\ingroup pb_ext
+\defgroup pb_ext_freertos FreeRTOS
+\brief FreeRTOS memory management and scheduler-based delay
+*/
diff --git a/lib/pbdrv/ext/freertos/pb-mem.c b/lib/pbdrv/ext/freertos/pb-mem.c
index b18d79f..6647f05 100644
--- a/lib/pbdrv/ext/freertos/pb-mem.c
+++ b/lib/pbdrv/ext/freertos/pb-mem.c
@@ -3,24 +3,29 @@
 #include "../../pb-mem.h"
 #include "../../pb-types.h"
 
+/// \ingroup pb_ext_freertos
 inline void * pb_malloc(size_t sz) {
 	return pvPortMalloc(sz);
 }
 
+/// \ingroup pb_ext_freertos
 inline void pb_free(void * ptr) {
 	vPortFree(ptr);
 }
 
+/// \ingroup pb_ext_freertos
 __weak inline void * pb_realloc(void * ptr, size_t sz) {
 	return NULL; // shit out of luck (don't use mpack_writer_init_growable)
 }
 
+/// \ingroup pb_ext_freertos
 __weak void * pb_memcpy(void * dest, const void * src, size_t sz) {
 	for (size_t offset = 0; offset < sz; offset++)
 		*((char*) dest + offset) = *((char*) src + offset);
 	return dest;
 }
 
+/// \ingroup pb_ext_freertos
 __weak int pb_memcmp(const void * a, const void * b, size_t sz) {
 	for (size_t offset = 0; offset < sz; offset++) {
 		int diff = *((char*) a + offset) - *((char*) b + offset);
diff --git a/lib/pbdrv/ext/freertos/pb-mod.c b/lib/pbdrv/ext/freertos/pb-mod.c
index 75495be..5c0aa36 100644
--- a/lib/pbdrv/ext/freertos/pb-mod.c
+++ b/lib/pbdrv/ext/freertos/pb-mod.c
@@ -3,6 +3,7 @@
 
 #include "../../pb-types.h"
 
+/// \ingroup pb_ext_freertos
 __weak void pb_mod_blocking_delay_ms(unsigned long ms) {
 	vTaskDelay(ms / portTICK_PERIOD_MS);
 }
diff --git a/lib/pbdrv/ext/index.dox b/lib/pbdrv/ext/index.dox
new file mode 100644
index 0000000..f7d2bc6
--- /dev/null
+++ b/lib/pbdrv/ext/index.dox
@@ -0,0 +1,24 @@
+// vim:ft=doxygen
+/**
+\ingroup pbdrv
+\ingroup pbdrv-mod
+\defgroup pb_ext Extensions
+\brief Platform-specific \ref pbdrv implementations
+
+Extensions provide platform-specific implementations for various functions used
+in \ref pbdrv, and allows \ref pbdrv to remain completely portable. Extensions
+are used in both \ref pbdrv and \ref pbdrv-mod.
+
+In order to use an extension, include the appropriate CMake lists file for your
+target platform after the \ref pbdrv include:
+
+```cmake
+# include pbdrv
+add_subdirectory(lib/pbdrv)
+
+# use stdlib extension (for use with C standard library)
+include(lib/pbdrv/ext/stdlib/include.cmake)
+
+```
+
+*/
diff --git a/lib/pbdrv/ext/stdlib/index.dox b/lib/pbdrv/ext/stdlib/index.dox
new file mode 100644
index 0000000..756af1e
--- /dev/null
+++ b/lib/pbdrv/ext/stdlib/index.dox
@@ -0,0 +1,6 @@
+// vim:ft=doxygen
+/**
+\ingroup pb_ext
+\defgroup pb_ext_stdlib stdlib
+\brief C stdlib memory management
+*/
diff --git a/lib/pbdrv/ext/stdlib/pb-mem.c b/lib/pbdrv/ext/stdlib/pb-mem.c
index b260c2c..328efbb 100644
--- a/lib/pbdrv/ext/stdlib/pb-mem.c
+++ b/lib/pbdrv/ext/stdlib/pb-mem.c
@@ -3,22 +3,27 @@
 
 #include "../../pb-mem.h"
 
+/// \ingroup pb_ext_stdlib
 inline void * pb_malloc(size_t sz) {
 	return malloc(sz);
 }
 
+/// \ingroup pb_ext_stdlib
 inline void pb_free(void * ptr) {
 	free(ptr);
 }
 
+/// \ingroup pb_ext_stdlib
 inline void * pb_realloc(void * ptr, size_t sz) {
 	return realloc(ptr, sz);
 }
 
+/// \ingroup pb_ext_stdlib
 void * pb_memcpy(void * dest, const void * src, size_t sz) {
 	return memcpy(dest, src, sz);
 }
 
+/// \ingroup pb_ext_stdlib
 int pb_memcmp(const void * a, const void * b, size_t sz) {
 	return memcmp(a, b, sz);
 }
diff --git a/lib/pbdrv/index.dox b/lib/pbdrv/index.dox
index e4a6c5f..eb0fd63 100644
--- a/lib/pbdrv/index.dox
+++ b/lib/pbdrv/index.dox
@@ -4,28 +4,62 @@
 \defgroup pbdrv pbdrv
 \brief Standalone puzzle bus driver
 
-pbdrv is a standalone portable static library for handling (i.e.
-(de)serialization) of puzzle bus messages.
+\ref pbdrv is a standalone portable static library for handling (i.e.
+(de)serialization) of puzzle bus messages. \ref pbdrv is meant for use within
+applications that handle puzzle bus messages, but are not puzzle modules
+themselves. For a complete puzzle module driver, please see \ref pbdrv-mod.
 
-\note Most \c pb_* functions have a weak implementation, which may be
-overwritten by a custom implementation. This allows you to use the default
-implementation where possible, and only implement extensions required for your
-puzzle module.
+If you order to use \ref pbdrv, you need to include this folder in your
+CMakeLists.txt file, include the \ref pb_ext "extension" for your target
+platform, and link the \c pbdrv library with your executable:
+
+```cmake
+# include pbdrv
+add_subdirectory(lib/pbdrv)
+
+# <use extension>
+
+# link with executable
+target_link_libraries(main pbdrv)
+```
 
-TODO: where to find drivers
-TODO: what are extensions
-TODO: what to do if there is no driver / extension
 
 \defgroup pbdrv-mod pbdrv-mod
 \brief Puzzle module driver (superset of \ref pbdrv)
 
 pbdrv-mod is a superset of \ref pbdrv, and includes functions specific to
-puzzle bus modules. pbdrv-mod compiles to an object file instead of a static
-library because it may depend on functions that rely on external libraries.
-pbdrv-mod is still considered standalone, but requires either using an existing
-driver, or (partially) implementing the driver functions.
+puzzle bus modules. \ref pbdrv-mod compiles to an object file instead of a
+static library because it may depend on functions that rely on external
+libraries. \ref pbdrv-mod is still considered standalone, but requires either
+using an existing \ref pb_drv "driver", or (partially) implementing the driver
+functions.
+
+Like \ref pbdrv, \ref pbdrv-mod can be used by including this folder in your
+CMakeLists.txt file and linking the library with your executable. A notable
+difference with \ref pbdrv-mod is that you do not need to include an extension.
+\ref pb_ext "Extensions" are still used by \ref pbdrv-mod, but they are
+included automatically by the target platform's \ref pb_drv "driver". The
+appropriate \ref pb_drv "driver" to load is also automatically detected.
+
+Example:
+
+```cmake
+# include pbdrv
+add_subdirectory(lib/pbdrv)
+
+# link with executable
+target_link_libraries(main pbdrv-mod)
+```
+
+\note In most cases, the \ref pb_hook "hooks" should be sufficient to realize
+extensions or custom behavior not provided by \ref pbdrv-mod.
+
+\note Most \c pb_* functions have a weak implementation, which may be
+overwritten by a custom implementation. This allows you to use the default
+implementation where possible, and only implement extensions required for your
+puzzle module.
 
-\copydetails pbdrv
+\see pbdrv
 
 \{
 
@@ -35,7 +69,7 @@ driver, or (partially) implementing the driver functions.
 Hooks are functions that allow the user to implement custom behavior (i.e.
 extend or conditionally replace the default handlers), without needing to
 completely overwrite the built-in handlers or understand the internals of \ref
-pbdrv.
+pbdrv-mod.
 
 \}
 
diff --git a/lib/pbdrv/pb-mod.h b/lib/pbdrv/pb-mod.h
index 75fcbec..3869e55 100644
--- a/lib/pbdrv/pb-mod.h
+++ b/lib/pbdrv/pb-mod.h
@@ -39,20 +39,11 @@ void pb_mod_blocking_delay_ms(unsigned long ms);
  * \defgroup pb_i2c I2C
  * \brief I2C send/receive handlers
  *
- * If there is no existing \ref pb_drv "driver" for the microcontroller on
- * which you want to use the puzzle bus driver, you may implement the following
- * in order to use pbdrv:
- *
- * - The \c pb_i2c_recv() function must be **called** for every received I2C
- *   message
- * - The \c pb_i2c_send() function must be **implemented** using the
- *   platform/device-specific I2C write function
- *
  * \{
  */
 
 /**
- * \brief handle a received message from the I2C bus (puzzle bus)
+ * \brief Handle a received message from the I2C bus (puzzle bus)
  *
  * This function attempts to parse an I2C message as a puzzle bus message, and
  * calls the appropriate handler for the message if it is considered valid.
@@ -67,7 +58,7 @@ void pb_mod_blocking_delay_ms(unsigned long ms);
  */
 void pb_i2c_recv(const uint8_t * buf, size_t sz);
 /**
- * \brief send a message in master-mode on the I2C bus (puzzle bus)
+ * \brief Send a message in master-mode on the I2C bus (puzzle bus)
  *
  * This function sends an I2C message to the address specified by \p i2c_addr.
  *
diff --git a/lib/pbdrv/pb-msg.h b/lib/pbdrv/pb-msg.h
index 33b697a..ff5bcde 100644
--- a/lib/pbdrv/pb-msg.h
+++ b/lib/pbdrv/pb-msg.h
@@ -46,6 +46,9 @@ pb_buf_t pb_msg_write(const pb_msg_t * msg);
 pb_msg_t * pb_msg_read(const pb_buf_t * buf);
 /**
  * \brief Recursively free fields of a \c pb_msg_t
+ *
+ * \note The \p msg pointer itself is also free'd by this function. You should
+ * set it to NULL afterwards to avoid confusion.
  */
 void pb_msg_free(pb_msg_t * msg);
 
diff --git a/lib/pbdrv/pb-serial.h b/lib/pbdrv/pb-serial.h
index d3d0007..79f08d7 100644
--- a/lib/pbdrv/pb-serial.h
+++ b/lib/pbdrv/pb-serial.h
@@ -8,23 +8,77 @@
 extern "C" {
 #endif
 
-#define __pb_cmd(name) \
-	pb_ser_r_t pb_ser_r_##name; \
-	pb_ser_w_t pb_ser_w_##name; \
-	pb_ser_free_t pb_ser_free_##name;
+/**
+ * \ingroup pbdrv
+ * \ingroup pbdrv-mod
+ * \defgroup pb_ser Serial
+ * \internal
+ * \brief Internal (de)serialization functions using mpack
+ *
+ * \{
+ */
 
+/**
+ * \brief Write (serialize) message fields using mpack
+ *
+ * \param writer Pointer to \c mpack_writer_t instance
+ * \param msg Pointer to message struct to read from
+ */
 typedef void pb_ser_w_t(mpack_writer_t * writer, const pb_msg_t * msg);
-pb_ser_w_t pb_ser_w;
-
+/**
+ * \brief Read (deserialize) message fields using mpack
+ *
+ * \param reader Pointer to \c mpack_reader_t instance
+ * \param msg Pointer to message struct to write to
+ */
 typedef void pb_ser_r_t(mpack_reader_t * reader, pb_msg_t * msg);
-pb_ser_r_t pb_ser_r;
-
+/**
+ * \brief Recursively free message struct fields
+ *
+ * \param msg Pointer to message struct to free
+ */
 typedef void pb_ser_free_t(pb_msg_t * msg);
+
+/**
+ * \brief Write the \ref pb_msg_t header fields and call another function for
+ * \p msg->cmd.
+ * \see pb_ser_w_t
+ */
+pb_ser_w_t pb_ser_w;
+/**
+ * \brief Read the \ref pb_msg_t header fields and call another function for \p
+ * msg->cmd.
+ * \see pb_ser_r_t
+ */
+pb_ser_r_t pb_ser_r;
+/**
+ * \brief Call another function for \p msg->cmd.
+ * \see pb_ser_free_t
+ */
 pb_ser_free_t pb_ser_free;
 
-__pb_cmd(cmd_prop)
-__pb_cmd(cmd_state)
-__pb_cmd(cmd_magic)
+//! Write the \ref pb_cmd_prop_t fields \see pb_ser_w_t
+pb_ser_w_t pb_ser_w_cmd_prop;
+//! Read the \ref pb_cmd_prop_t fields \see pb_ser_r_t
+pb_ser_r_t pb_ser_r_cmd_prop;
+//! Free the \ref pb_cmd_prop_t fields \see pb_ser_free_t
+pb_ser_free_t pb_ser_free_cmd_prop;
+
+//! Write the \ref pb_cmd_state_t fields \see pb_ser_w_t
+pb_ser_w_t pb_ser_w_cmd_state;
+//! Read the \ref pb_cmd_state_t fields \see pb_ser_r_t
+pb_ser_r_t pb_ser_r_cmd_state;
+//! Free the \ref pb_cmd_state_t fields \see pb_ser_free_t
+pb_ser_free_t pb_ser_free_cmd_state;
+
+//! Write the \ref pb_cmd_magic_t fields \see pb_ser_w_t
+pb_ser_w_t pb_ser_w_cmd_magic;
+//! Read the \ref pb_cmd_magic_t fields \see pb_ser_r_t
+pb_ser_r_t pb_ser_r_cmd_magic;
+//! Free the \ref pb_cmd_magic_t fields \see pb_ser_free_t
+pb_ser_free_t pb_ser_free_cmd_magic;
+
+/// \}
 
 #ifdef __cplusplus
 }
diff --git a/main/pbdrv.h b/main/pbdrv.h
index a751000..9496aa9 100644
--- a/main/pbdrv.h
+++ b/main/pbdrv.h
@@ -3,35 +3,41 @@
 #include "pb-types.h"
 
 /**
- * This is the RP2040 puzzle bus driver. This file is no longer inside
- * lib/pb//rp2040 as it is tightly coupled to both the pico-sdk and
- * freertos functions. I have tried to get FreeRTOS to play nicely with the
- * CMake subproject layout, but the pico-sdk and the rp2040 port of freertos
- * both rely on CMake's import() functionality, which makes using FreeRTOS in a
- * libary context extremely messy.
+ * \ingroup pb_drv
+ * \defgroup pb_drv_rp2040 RP2040
+ * \brief Raspberry Pi Pico and Pico W driver
  *
- * The workaround implemented in this driver was already kind of messy, and a
- * different microcontroller should be used for the main controller instead.
+ * \note This file is no longer inside `lib/pbdrv/drv/rp2040` as it is tightly
+ * coupled to both the pico-sdk and FreeRTOS functions. I have tried to get
+ * FreeRTOS to play nicely with the CMake subproject layout, but the pico-sdk
+ * and the RP2040 port of FreeRTOS both rely on CMake's import() functionality,
+ * which makes using FreeRTOS in a libary context extremely messy.
+ *
+ * \warning The workaround implemented in this driver was already kind of
+ * messy, and **a different microcontroller should be used for the main
+ * controller instead**. Please see the handover document for more details.
+ *
+ * \{
  */
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
-//! puzzle bus driver setup
+//! Puzzle bus driver setup
 void pb_setup();
 
 /**
- * While the RP2040's datasheet claims it supports multi-master configurations
- * by implementing bus arbitration, it does not natively support a mode where
- * it is configured as a (multi-)master with a slave address, such that it can
- * be addressed by other multi-masters. This function includes a hacky
- * workaround that teporarily sets the RP2040 to I2C master mode to send a
- * message, and then restores it back to slave mode.
+ * \note While the RP2040's datasheet claims it supports multi-master
+ * configurations by implementing bus arbitration, it does not natively support
+ * a mode where it is configured as a (multi-)master with a slave address, such
+ * that it can be addressed by other multi-masters. This function includes a
+ * hacky workaround that teporarily sets the RP2040 to I2C master mode to send
+ * a message, and then restores it back to slave mode.
  *
- * This approach results in some received frames being (partially) dropped in
- * the time period between the invocation of this function and the bus becoming
- * idle (and the message is sent).
+ * \warning This approach results in some received frames being (partially)
+ * dropped in the time period between the invocation of this function and the
+ * bus becoming idle (and the message is sent).
  */
 void pb_i2c_send(i2c_addr_t addr, const uint8_t * buf, size_t sz);
 
@@ -39,13 +45,19 @@ void pb_i2c_send(i2c_addr_t addr, const uint8_t * buf, size_t sz);
  * \brief Scan the bus for I2C slaves, and send handshake messages to ACK-ing
  * slaves.
  *
- * As a result of the RP2040 hardware limitations detailed at the top of this
- * file, this function is also implemented in this file, even through it does
- * not belong to the puzzle bus driver. In order to not miss any handshake
- * responses, the bus should remain busy during the entire scan.
+ * \note As a result of the RP2040 hardware limitations, this function is also
+ * implemented in this file, even though it does not belong to the puzzle bus
+ * driver.
+ *
+ * \warning In order to not miss any handshake responses, the bus should remain
+ * busy during the entire scan. The \c nostop parameter of the \c
+ * i2c_write_timeout_us() function from the pico-sdk does not seem to keep the
+ * bus busy.
  */
 void bus_scan();
 
+/// \}
+
 #ifdef __cplusplus
 }
 #endif