[PATCH v4 0/3] Add support for Sitronix ST7571 LCD controller

[Marcus Folkesson]

This series add support for the ST7571 LCD Controller.
It is a 4 gray scale dot matrix LCD controller that supports several
interfaces such as SPI, I2C and a 8bit parallell port.
The controlelr supports both monochrome and grayscale displays.

This driver only supports the I2C interface, but all common parts could
easily be put into a common file to be used with other interfaces.
I only have I2C to test with.

The device is a little defiant, it tends to NAK some commands, but all
commands takes effect, hence the I2C_M_IGNORE_NAK flag.

Signed-off-by: Marcus Folkesson <marcus.folkesson@xxxxxxxxx>
---
Changes in v4:
- (dt-binding) Add sitronix,grayscale property
- Describe why ignore_nack may be needed
- Make drm_to_st7571 an inline function
- Add support to clear screen
- Change from C2 to R2
- Add support for XRGB8888
- Use dev_err_probe() where appropriate
- Make Kconfig config depend on MMU
- Introduce device data to prepare for support for other chips
- Add support for drm_encoder_helper_funcs.atomic_en(dis)able
- Link to v3: https://lore.kernel.org/r/20250408-st7571-v3-0-200693efec57@xxxxxxxxx

Changes in v3:
- (dt-binding) Use 'Controller' rather than 'Panel' in texts
- (dt-binding) Constrain the reg property
- (dt-binding) Remove panel-timing description
- (dt-binding) Change description
- Mostly cosmetic changes in the driver code
- Don't call drm_atomic_helper_shutdown() in remove()
- Link to v2: https://lore.kernel.org/r/20250404-st7571-v2-0-4c78aab9cd5a@xxxxxxxxx

Changes in v2:
- Reworked pretty much the whole driver to not use obsolete code.
- Use panel and timing bindings to specify resolution and panel size
- Link to v1: https://lore.kernel.org/r/20250402-st7571-v1-0-351d6b9eeb4a@xxxxxxxxx

---
Marcus Folkesson (3):
      dt-bindings: display: Add Sitronix ST7571 LCD Controller
      drm/st7571-i2c: add support for Sitronix ST7571 LCD controller
      MAINTAINERS: add entry for Sitronix ST7571 LCD Controller

 .../bindings/display/sitronix,st7571.yaml          |  73 ++
 MAINTAINERS                                        |   6 +
 drivers/gpu/drm/tiny/Kconfig                       |  11 +
 drivers/gpu/drm/tiny/Makefile                      |   1 +
 drivers/gpu/drm/tiny/st7571-i2c.c                  | 994 +++++++++++++++++++++
 5 files changed, 1085 insertions(+)
---
base-commit: 1e26c5e28ca5821a824e90dd359556f5e9e7b89f
change-id: 20250401-st7571-9382b9cfc03f

Best regards,
-- 
Marcus Folkesson <marcus.folkesson@xxxxxxxxx>