/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
 * Header file for:
 * Driver for Sitronix ST7571, a 4 level gray scale dot matrix LCD controller
 *
 * Copyright (C) 2025 Marcus Folkesson <marcus.folkesson@gmail.com>
 */

#ifndef __ST7571_H__
#define __ST7571_H__

#include <drm/drm_connector.h>
#include <drm/drm_crtc.h>
#include <drm/drm_drv.h>
#include <drm/drm_encoder.h>
#include <drm/drm_format_helper.h>

#include <linux/regmap.h>

enum st7571_color_mode {
        ST7571_COLOR_MODE_GRAY = 0,
        ST7571_COLOR_MODE_BLACKWHITE = 1,
};

struct st7571_device;

struct st7571_panel_constraints {
        u32 min_nlines;
        u32 max_nlines;
        u32 min_ncols;
        u32 max_ncols;
        bool support_grayscale;
};

struct st7571_panel_data {
        int (*init)(struct st7571_device *st7571);
        int (*parse_dt)(struct st7571_device *st7571);
        struct st7571_panel_constraints constraints;
};

struct st7571_panel_format {
        void (*prepare_buffer)(struct st7571_device *st7571,
                               const struct iosys_map *vmap,
                               struct drm_framebuffer *fb,
                               struct drm_rect *rect,
                               struct drm_format_conv_state *fmtcnv_state);
        int (*update_rect)(struct drm_framebuffer *fb, struct drm_rect *rect);
        enum st7571_color_mode mode;
        const u8 nformats;
        const u32 formats[];
};

struct st7571_device {
        struct drm_device drm;
        struct device *dev;

        struct drm_plane primary_plane;
        struct drm_crtc crtc;
        struct drm_encoder encoder;
        struct drm_connector connector;

        struct drm_display_mode mode;

        const struct st7571_panel_format *pformat;
        const struct st7571_panel_data *pdata;
        struct gpio_desc *reset;
        struct regmap *regmap;

        bool grayscale;
        bool inverted;
        u32 height_mm;
        u32 width_mm;
        u32 startline;
        u32 nlines;
        u32 ncols;
        u32 bpp;

        /* Intermediate buffer in LCD friendly format */
        u8 *hwbuf;

        /* Row of (transformed) pixels ready to be written to the display */
        u8 *row;
};

extern const struct st7571_panel_data st7567_config;
extern const struct st7571_panel_data st7571_config;

struct st7571_device *st7571_probe(struct device *dev, struct regmap *regmap);
void st7571_remove(struct st7571_device *st7571);

#endif /* __ST7571_H__ */