This patch series adds support for the Mayqueen Pixpaper e-ink display panel, controlled via SPI.
The series includes: - A new vendor-prefix entry for "mayqueen" - Device tree binding documentation for the Pixpaper panel - A DRM tiny driver implementation for the Pixpaper panel - A MAINTAINERS entry for the Pixpaper DRM driver and binding The panel supports 122x250 resolution with XRGB8888 format and uses SPI, along with GPIO lines for reset, busy, and data/command control. The driver has been tested on: - Raspberry Pi 2 Model B with Linux kernel 6.16. --- Changes in v5: - Integrated pixpaper-regs.h into pixpaper.c - Added "L: dri-devel@lists.freedesktop.org" in MAINTAINERS - Renamed helper to pixpaper_wait_for_panel() - Fixed endianness with __le32 + le32_to_cpu() - Replaced drm_err() with drm_err_once() - Simplified connector get_modes() via drm_connector_helper_get_modes_fixed() - Dropped manual drm_mode_validate_size() check - Moved resolution validation to CRTC mode_valid() - Link to v4: https://lore.kernel.org/r/20250805-drm-v4-0-94eaec015...@gmail.com Changes in v4: - Applied BIT() macro for all register bit definitions (per checkpatch) - Fixed alignment and indentation based on checkpatch suggestions - Removed unnecessary blank lines after braces - Fixed universal plane init() call indentation - Link to v3: https://lore.kernel.org/r/20250721-drm-v3-0-e16c3cee7...@gmail.com Changes in v3: - MAINTAINERS - Added pixpaper-regs.h - Kconfig - Rename config symbol to DRM_PIXPAPER (drop TINYDRM_ prefix). - Reordered Kconfig select lines alphabetically. - Code structure & style - Fix include order: move <linux/> headers above <drm/> headers. - Removed forward declarations; placed static functions next to usage - Switched logging to drm_err()/drm_warn()/drm_dbg() (legacy DRM_ERROR/WARN removed) - Remove dev_info() statements. - Switched encoder type to DRM_MODE_ENCODER_NONE - Moved pixpaper_panel_hw_init() from atomic_enable() to probe() to avoid redundant hardware init. - Use helper to_pixpaper_panel() instead of container_of() on crtc. - Robustness - Added timeout + warning in pixpaper_wait_busy() to ensure robustness if BUSY line gets stuck. - Introduced struct pixpaper_error_ctx to propagate SPI/GPIO errors - Clean‑ups - Removed drm_plane_enable_fb_damage_clips() (full‑frame updates) - Removed noisy info prints; kept drm_dbg() only where helpful - Consolidated all magic register values/commands into new pixpaper-regs.h with datasheet‑aligned naming - Memory helpers - Driver now uses GEM SHMEM helpers; GEM DMA helpers dropped (panel has no bus‑mastering DMA) - Functionality fixes - Rewrote pack_pixels_to_byte() to correctly handle 4-color (B/W/R/Y) layout based on expected panel color encoding - DRM callback safety - Add missing drm_dev_enter()/drm_dev_exit() in callbacks. - Tags added - Reviewed-by: Rob Herring <r...@kernel.org> (from v1) - Acked-by: Rob Herring <r...@kernel.org> (from v1) - Acked-by: Krzysztof Kozlowski <krzysztof.kozlow...@linaro.org> (from v2) - Link to v2: https://lore.kernel.org/r/20250714-drm-v2-0-5d1a2e127...@gmail.com Changes in v2: - Reordered patches so that DT bindings come before the driver (suggested by Rob Herring) - Fixed sparse warning: removed duplicate `.reset` initializer in `pixpaper_plane_funcs` - Fixed checkpatch issues reported by Media CI: - Removed unnecessary blank line before closing brace - Moved opening parentheses up to function call lines (e.g., `DRM_WARN(...)`) - Fixed alignment of conditionals - Fixed `dev_warn(` and `drm_universal_plane_init(` formatting - Thanks to Rob Herring for ack on vendor-prefix patch - Link to v1: https://lore.kernel.org/r/20250708-drm-v1-0-45055fdad...@gmail.com Thanks to all reviewers for feedback across earlier versions. Best regards, LiangCheng Wang <zaq14...@gmail.com> --- LiangCheng Wang (2): dt-bindings: display: Add Mayqueen Pixpaper e-ink panel drm: tiny: Add support for Mayqueen Pixpaper e-ink panel Wig Cheng (1): dt-bindings: vendor-prefixes: Add Mayqueen name .../bindings/display/mayqueen,pixpaper.yaml | 63 ++ .../devicetree/bindings/vendor-prefixes.yaml | 2 + MAINTAINERS | 7 + drivers/gpu/drm/tiny/Kconfig | 15 + drivers/gpu/drm/tiny/Makefile | 1 + drivers/gpu/drm/tiny/pixpaper.c | 1171 ++++++++++++++++++++ 6 files changed, 1259 insertions(+) --- base-commit: b320789d6883cc00ac78ce83bccbfe7ed58afcf0 change-id: 20250708-drm-6021df0715d7 Best regards, -- LiangCheng Wang <zaq14...@gmail.com>
