docs/Add research into supporting the Raspberry Pi 5 (#557)

* Add research into extending gpio support

* Update gpio-support-research.md

Author: Liquidscroll

docs/Splashkit/Extensions/GPIO Support/gpio-support-research.md

@@ -0,0 +1,104 @@
+## Spike Outcomes
+
+---
+
+**Title:** Extending SplashKit Library to Support Raspberry Pi 5 and Generic Linux SBCs
+
+**Author:** Jonathan Tynan
+
+## Goals / Deliverables
+
+- This report documenting findings and recommendations.
+
+## Tasks undertaken
+
+- Confirming that pigpio does not support Raspberry Pi 5.
+- Develop overview of major projects that fit our requirements.
+- Explored gpiod/libgpiod for GPIO control on Raspberry Pi 5.
+- Investigated lgpio/rgpio for remote GPIO operations and PWM support.
+- Evaluating the availability and suitability of C/C++ bindings for each library.
+
+## What we found out
+
+Through this spike, we explored various libraries and interfaces for GPIO and PWM control across Raspberry Pi 5 and generic Linux SBCs. Below are our detailed findings:
+
+### [WiringPi](https://github.com/WiringPi/WiringPi/)
+
+- Pros:
+  - Supports both GPIO and PWM operations on Raspberry Pi models, including the Raspberry Pi 5.
+  - Offers a simple interface well-suited to SplashKit's existing structure, facilitating straightforward integration.
+  - Community-driven forks are still maintained, providing ongoing updates.
+- Cons:
+  - Lacks support for remote GPIO operations, a crucial feature for SplashKit.
+  - Since the original project was deprecated, relying on community-maintained forks raises concerns about long-term support and stability.
+  - May not be a reliable choice for future development due to potential abandonment.
+
+### [lgpio/rgpio](https://github.com/joan2937/lg)
+
+- Pros:
+  - Developed by the same creator as pigpio, offering a familiar interface and functionality.
+  - Supports remote GPIO operations out-of-the-box, aligning with SplashKit's requirements.
+  - Provides basic PWM functionality.
+  - Compatible with the Raspberry Pi 5 and a range of Linux SBCs beyond Raspberry Pi.
+  - Has C/C++ bindings suitable for our project.
+- Cons:
+  - Being a newer project, it lacks the maturity and extensive community support of pigpio.
+  - Potential risks in terms of long-term support and unanticipated bugs.
+  - Limited documentation could extend the integration and development timeline.
+
+### [gpiod/libgpiod](https://github.com/brgl/libgpiod)
+
+- Pros:
+  - The new Linux kernel interface for GPIO control, providing a unified approach across different Linux-based SBCs.
+  - Offers broad compatibility with modern Linux systems, making it future-proof.
+  - Supports Raspberry Pi 5 and generic SBCs.
+  - Provides C bindings compatible with our C/C++ project.
+- Cons:
+  - Integration may be complex due to structural differences from SplashKit’s current setup, requiring significant refactoring.
+  - Does not natively support PWM; implementing PWM would require a custom solution using the sysfs interface or gpiomem, which are more complex and less performant.
+  - Lacks remote GPIO support, limiting its utility in replacing pigpio in SplashKit.
+ 
+These libraries, in the writers opinion, are currently the most suitable for enable GPIO operations on the Raspberry Pi 5, and potentially on other linux SBC's.
+Whether they are ready for integration into SplashKit, is another question entirely. 
+
+## Open issues/risks
+
+- PWM Functionality:
+  - Implementing PWM with gpiod/libgpiod requires a custom solution, potentially leading to increased complexity and maintenance overhead.
+  - The performance of such a custom implementation may not meet SplashKit's requirements.
+
+- Remote GPIO Operations:
+  - Maintaining remote GPIO capabilities is crucial for SplashKit.
+  - WiringPi and gpiod/libgpiod lack this feature, necessitating either a hybrid approach or alternative libraries.
+
+- Library Maturity and Support:
+  - Both lgpio/rgpio and gpiod/libgpiod are relatively new, and this may pose risks regarding long-term support.
+  - Limited documentation might increase the learning curve and integration time.
+
+
+## Recommendations
+
+- Further Evaluation of lgpio/rgpio:
+  - Given its support for GPIO control, remote operations, PWM functionality, and C/C++ bindings, lgpio/rgpio is a strong candidate.
+  - Conduct comprehensive testing to assess performance, stability, and compatibility with SplashKit.
+  
+- Explore Alternatives:
+  - This is by no means an exhaustive list of options; other libraries may better fulfill SplashKit's requirements.
+  - Investigate additional libraries that can provide the needed functionalities, possibly with more mature ecosystems.
+
+- Additional Spikes and Testing:
+  - Plan further spikes focused on integrating and testing different GPIO libraries.
+  - Perform performance benchmarking, especially for time-sensitive operations like PWM and remote GPIO control.
+
+- Long-Term Strategy:
+  - Monitor updates to pigpio or its forks for potential future support of Raspberry Pi 5 and generic SBCs.
+  - Stay informed about emerging libraries and technologies that could meet SplashKit's evolving requirements.
+  
+  
+## Additional Resources
+
+- [lgpio/rgpio website](https://abyz.me.uk/lg/index.html)
+- [gpiod/libgpiod additional information](https://docs.kernel.org/userspace-api/gpio/chardev.html) 
+  - Note: libgpiod is the library provided by the kernel to interact with the linux GPIO character device.
+- [Additional Linux Kernel GPIO drivers](https://docs.kernel.org/driver-api/gpio/drivers-on-gpio.html)
+