How should (does?) this library expose register manipulation to the consumer?

[EmilNorden]

Hi there.
I started using a 7.5" V2 display for a project and have started working on integrating this crate into my project.

I experienced quite a bit of flickering when doing full-frame updates so I looked into the Waveshare Arduino examples and saw that they have two different initialization routines for the display: One "normal init", that seems to perform the same configuration as this library does, and one "fast init" that minimizes flickering.

There is also a "partial init" that sets up registers to appropriate values for partial updates, but I haven't gotten to that yet.

So this leads me to the question in the title of this post: The way the display is initializes should not be a "one size fits all" solution and consumers might have different needs. So how should this be exposed?

Just throwing some possible solutions out there:

• Make fn command(...) / fn cmd_with_data(...) / fn send_data(...) public
  • Simple solution for maintainers of the crate, more tedious for consumers who will need to learn the datasheet to do anything useful.
• Abstract away registers into one or several configuration structs and implement something like set_configuration.
  • Provides the same level of flexibility as the point above, but it costs more. Perhaps not worth it?
• Make use of Rusts type system and encode the different "modes" as typestates:
  • Better consumer ergonomics, but might not fit into the low level style of the driver right now.

  let device =
    Epd7in5::new(&mut spi, busy, dc, rst, &mut delay, None).expect("eink initalize error");
  let fast_device = device.into_fast_mode() // Consumes 'self' and returns a device with the appropriate configuration.
  // Perform "fast" updates on the display
  let partial_device = device.into_partial_mode() // Consumes 'self' and returns a device configured for partial updates

Or is there already a design in place that I have missed? Perhaps there is something totally obvious that I have missed. Let me know your thoughts.