BeagleBoard/GSoC/2022 Proposal/GreybusforZephyrUpdates

=Proposal = About Student: Harshil Bhatt Mentors: Vaishnav Achath, Jason Kridner

=Status= This project is currently just a proposal.

=Proposal=
 * Please complete the requirements listed on the ideas page and fill out this template.
 * The PR for "Hello World" task #163

About you
Github: harshilbhatt2001 School: Manipal Institute of Technology Country: India Primary language : English Typical work hours: 2PM-1AM Indian Standard Time Previous GSoC participation: This is my first time applying to participate for GSoC.

About your project
Project name: Greybus for Zephyr Updates

Description
In 10-20 sentences, what are you making, for whom, why and with what technologies (programming languages, etc.)? (We are looking for open source SOFTWARE submissions.)

Greybus is an application layer for UniPro. UniPro follows the classical OSI model, and UniPro communications happen over bidirectional connections between entities. The physical bus is attached to the connected device, which will be running Zephyr. A virtual bus, corresponding to the physical bus on the connected device, is created on the Linux side. The functionality of the physical bus and virtual bus appears the same to a user. Greybus is used to exchange bus-specific messages and data between the connected device and Linux.

Currently, the following modules are supported by greybus-for-zephyr
 * GPIO
 * I2C
 * SPI

The aim of this project is to support all relevant peripherals (UART, PWM, ADC, SPIO IRQ) on BeagleConnect Freedom on Greybus for Zephyr. This involves adding platform specific changes to enable these protocols and interface to existing NuttX sources. The device drivers will be merged into the kernel. These device drivers will be compatible with mikrobus add-on boards, and each peripheral will be tested over a mikrobus add-on board over Greybus using its corresponding driver in the kernel.

Timeline
Provide a development timeline with a milestone each of the 11 weeks and any pre-work. (A realistic timeline is critical to our selection process.)

Experience and approach

 * I was a firmware engineer intern at Sensegrass, and an Embedded System Engineer at Retisense, where I worked on BLE, power optimization and memory management. I picked up the Zephyr RTOS for developing a wireless body area network and deployed it on nrf52.
 * I have developed drivers for common peripherals (SPI, UART, I2C, ADC, GPIO IRQ, etc) using either bare-metal C or an underlying RTOS.

Contingency
What will you do if you get stuck on your project and your mentor isn’t around?

There is a lot of documentation on Greybus, and some drivers (GPIO) have been merged into the Linux kernel which should provide a good reference. Along with this, the Beagle and Zephyr have an active community which can be looked to for help.

Benefit
If successfully completed, what will its impact be on the BeagleBoard.org community? Include quotes from BeagleBoard.org community members who can be found on http://beagleboard.org/discuss and http://bbb.io/gsocchat.

The major advantage of Greybus is that drivers can be maintained in Linux rather than microcontroller firmware. This gives us the ability to reuse existing Linux device drivers to access remote devices and reduces development time significantly. Since most application logic is kept out of the microcontroller firmware and in a better centralized location, updates can be better tested and deployed frequently.

Misc
Please complete the requirements listed on the ideas page. Provide link to pull request.

Suggestions
Is there anything else we should have asked you?