Added madctl parameter to ILI9341 driver for hardware rotation and RGB/BGR control, enabling faster rendering and more flexibility

[ritesh006]

Summary

This PR adds support for passing a madctl parameter to the ILI9341 driver, allowing developers to directly control hardware rotation via the MADCTL register.
It also preserves support for BGR/RGB selection and inversion.

Motivation

Currently, display rotation relies on displayio’s software-based handling, which can be inefficient.
By exposing MADCTL, developers can take advantage of the LCD controller’s built-in rotation logic, which improves performance (especially for OnDiskBitmaps).

Changes

• Added an optional madctl parameter to the ILI9341 constructor.
• Retained existing bgr and invert options.
• Updated initialization sequence handling to correctly append MADCTL.
• Updated README usage examples to include madctl.

Tests

• Added unit tests (test_madctl.py) covering:
  • Default RGB encoding
  • BGR encoding
  • Custom MADCTL overrides
• All tests pass locally.

Related Issues

Closes #26 ("Make it easy to set MADCTL for rotation").

[ritesh006]

Please review this commit

[ladyada]

reviewed. we will not merge, please use/add/adapt kwargs instead of hardcoding MADCTL writes

[ritesh006]

Hi @ladyada your review comment addressed please take a look.

[ladyada]

hi, to be clear: we will not accept passing in MADCTL. instead, you can add kwargs for any/each setting that may be required (e.g. color order)

[ritesh006]

Hi @ladyada I’ve updated this PR as suggested: replaced raw madctl with a color_order kwarg (default "RGB", optional "BGR"), kept bgr for compatibility, and updated docs/tests. Ready for re-review.