Status:
- = Planned.
X = In progress, some work done.
* = Done.
? = Not sure if worth the effort or useful at all.
N = Decided against.

Within 2.1.x
* Binary Semaphores on top of Counting Semaphores.
* Direct unbuffered UART driver.
  Requirements: low level, callbacks, DMA capable, state machines buildable
                on top, support data words greater than 8 bits, callback for
                "last byte transmitted (RS485)", simple implementation,
                verifiable.
* Rework STM32 drivers to use friendly IRQ names and centralized DMA macros.
* I-class functions for the ADC/PWM drivers.
* All the device driver structures must have a fields extension macro and
  initializer hook.
* All the device driver callbacks must have the driver pointer as first
  parameter.
* Change the SPI driver to be able to work asynchronously using callbacks,
  keep the synchronous APIs available as option.
* Update the STM32 SPI driver to the new model.
* Make the ADC driver have the same synchronous/asynchronous API of the
  new SPI driver model.
* General HAL improvements.
* Update the AT91SAM7 SPI driver (DMA and/or ISR).
  * Verify the FatFs demo on both the AT91SAM7X and AT91SAM7S.
* Update the LPC214x SPI driver (ISR).
  * Verify the LPC214x FatFs demo.
X Write a new SPI driver for LPC1xxx (ISR)(it should be very close to the
  LPC214x one).
N Evaluate if to add a synchronous API to the UART driver, eventually do so.
X Global documentation reorganization in order to allow both separate documents
  and the usual blob document.
X PDF generation from the documentation system (only separate documents, not
  the blob).
- Automatic compilation and upload of the various documents on the web site
  (doxygen + rsync).
- STM8L official HAL support, it will have to be separated from the STM8S/STM8A
  HAL because it is very different, actually it looks much more like a
  mini STM32, most STM32 drivers will only require few changes it also has
  a very similar DMA (waiting for the new STM8L-Discovery kit).
- Add the STM32VL to the official STM32 HAL support (waiting for the new
  STM32-Discovery kit).
- New STM8S/A SPI driver.
X Evaluate a new API for the SPI driver enabling quick transfers of few bytes
  in polled mode.
X Except for the above, bug fixing only until the 2.2.0 release.

Within 2.3.x (hopefully)
- Resist doing more changes and optimizations to the kernel.
X File System infrastructure.
  - Official FatFs wrapper using the new infrastructure, dedicated test suite.
X I2C device driver class support and at least one implementation (test
  hardware missing).
- Serial over UART complex driver driver, evaluate from the performance
  results if to make obsolete the current dedicated Serial driver.
- Shared DMA channels support in the STM32/STM8L HALs.
- New device driver models: RTC, WDG, DAC, USB, Systick, Battery Monitor.
- MAC driver for STM32F107 (hardware missing).
- Device drivers for STM8/STM8L (SPI, ADC, PWM, bring it on par with STM32).
- Support for more compilers (ARMCMx only initially).
- Support for not just Makefiles (Ride7, Crossworks etc).
- Batch testing of the ARM7/ARMCMx port using OpenOCD, with reports.
- Debug-related features and tools.
- Add a *very simple* ADC API for single one shot sampling (implement it as
  an injected conversion on the STM32).
- Update C++ wrapper (Heap, Pools, Mailboxes and any new feature).
- Threads Pools manager in the library.

Later but within 2.x.x
- Transactional file system.
- Dedicated TCP/IP stack.
? ISO7816 driver over UART driver, both reader and card side (hardware
  missing).
- Merge the Coldfire branch in mainline (hardware missing).
- Merge the H8S branch in mainline (hardware missing).
- MAC driver revision in order to support copy-less operations, this will
  require changes to lwIP or a new TCP/IP stack however.

Ideas for 3.x.x:
- High resolution timers and tickless kernel.
- Multicore support.

Side projects:
X ChibiOS Wizard, UML modeling and ChibiOS applications code and
  documentation generator.
? File System
- Visual debugger/monitor interfaced through OpenOCD.