/*
 * Copyright (c) 2015 MediaTek Inc.
 * Author: CK Hu <ck.hu@mediatek.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

#include <drm/drmP.h>
#include <drm/drm_atomic.h>
#include <drm/drm_atomic_helper.h>
#include <drm/drm_plane_helper.h>

#include "mtk_drm_crtc.h"
#include "mtk_drm_ddp_comp.h"
#include "mtk_drm_drv.h"
#include "mtk_drm_fb.h"
#include "mtk_drm_gem.h"
#include "mtk_drm_plane.h"

static const u32 formats[] = {
        DRM_FORMAT_XRGB8888,
        DRM_FORMAT_ARGB8888,
        DRM_FORMAT_RGB565,
        DRM_FORMAT_UYVY,
        DRM_FORMAT_YUYV,
};

static void mtk_plane_reset(struct drm_plane *plane)
{
        struct mtk_plane_state *state;

        if (plane->state) {
                __drm_atomic_helper_plane_destroy_state(plane->state);

                state = to_mtk_plane_state(plane->state);
                memset(state, 0, sizeof(*state));
        } else {
                state = kzalloc(sizeof(*state), GFP_KERNEL);
                if (!state)
                        return;
                plane->state = &state->base;
        }

        state->base.plane = plane;
        state->pending.format = DRM_FORMAT_RGB565;
}

static struct drm_plane_state *mtk_plane_duplicate_state(struct drm_plane *plane)
{
        struct mtk_plane_state *old_state = to_mtk_plane_state(plane->state);
        struct mtk_plane_state *state;

        state = kzalloc(sizeof(*state), GFP_KERNEL);
        if (!state)
                return NULL;

        __drm_atomic_helper_plane_duplicate_state(plane, &state->base);

        WARN_ON(state->base.plane != plane);

        state->pending = old_state->pending;

        return &state->base;
}

static void mtk_drm_plane_destroy_state(struct drm_plane *plane,
                                        struct drm_plane_state *state)
{
        __drm_atomic_helper_plane_destroy_state(state);
        kfree(to_mtk_plane_state(state));
}

static const struct drm_plane_funcs mtk_plane_funcs = {
        .update_plane = drm_atomic_helper_update_plane,
        .disable_plane = drm_atomic_helper_disable_plane,
        .destroy = drm_plane_cleanup,
        .reset = mtk_plane_reset,
        .atomic_duplicate_state = mtk_plane_duplicate_state,
        .atomic_destroy_state = mtk_drm_plane_destroy_state,
};

static int mtk_plane_atomic_check(struct drm_plane *plane,
                                  struct drm_plane_state *state)
{
        struct drm_framebuffer *fb = state->fb;
        struct drm_crtc_state *crtc_state;

        if (!fb)
                return 0;

        if (!mtk_fb_get_gem_obj(fb)) {
                DRM_DEBUG_KMS("buffer is null\n");
                return -EFAULT;
        }

        if (!state->crtc)
                return 0;

        crtc_state = drm_atomic_get_crtc_state(state->state, state->crtc);
        if (IS_ERR(crtc_state))
                return PTR_ERR(crtc_state);

        return drm_atomic_helper_check_plane_state(state, crtc_state,
                                                   DRM_PLANE_HELPER_NO_SCALING,
                                                   DRM_PLANE_HELPER_NO_SCALING,
                                                   true, true);
}

static void mtk_plane_atomic_update(struct drm_plane *plane,
                                    struct drm_plane_state *old_state)
{
        struct mtk_plane_state *state = to_mtk_plane_state(plane->state);
        struct drm_crtc *crtc = plane->state->crtc;
        struct drm_framebuffer *fb = plane->state->fb;
        struct drm_gem_object *gem;
        struct mtk_drm_gem_obj *mtk_gem;
        unsigned int pitch, format;
        dma_addr_t addr;

        if (!crtc || WARN_ON(!fb))
                return;

        gem = mtk_fb_get_gem_obj(fb);
        mtk_gem = to_mtk_gem_obj(gem);
        addr = mtk_gem->dma_addr;
        pitch = fb->pitches[0];
        format = fb->format->format;

        addr += (plane->state->src.x1 >> 16) * fb->format->cpp[0];
        addr += (plane->state->src.y1 >> 16) * pitch;

        state->pending.enable = true;
        state->pending.pitch = pitch;
        state->pending.format = format;
        state->pending.addr = addr;
        state->pending.x = plane->state->dst.x1;
        state->pending.y = plane->state->dst.y1;
        state->pending.width = drm_rect_width(&plane->state->dst);
        state->pending.height = drm_rect_height(&plane->state->dst);
        wmb(); /* Make sure the above parameters are set before update */
        state->pending.dirty = true;
}

static void mtk_plane_atomic_disable(struct drm_plane *plane,
                                     struct drm_plane_state *old_state)
{
        struct mtk_plane_state *state = to_mtk_plane_state(plane->state);

        state->pending.enable = false;
        wmb(); /* Make sure the above parameter is set before update */
        state->pending.dirty = true;
}

static const struct drm_plane_helper_funcs mtk_plane_helper_funcs = {
        .atomic_check = mtk_plane_atomic_check,
        .atomic_update = mtk_plane_atomic_update,
        .atomic_disable = mtk_plane_atomic_disable,
};

int mtk_plane_init(struct drm_device *dev, struct drm_plane *plane,
                   unsigned long possible_crtcs, enum drm_plane_type type)
{
        int err;

        err = drm_universal_plane_init(dev, plane, possible_crtcs,
                                       &mtk_plane_funcs, formats,
                                       ARRAY_SIZE(formats), NULL, type, NULL);
        if (err) {
                DRM_ERROR("failed to initialize plane\n");
                return err;
        }

        drm_plane_helper_add(plane, &mtk_plane_helper_funcs);

        return 0;
}