// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2015 Texas Instruments
 * Author: Jyri Sarha <jsarha@ti.com>
 */

#include <drm/drm_atomic.h>
#include <drm/drm_atomic_helper.h>
#include <drm/drm_fourcc.h>
#include <drm/drm_framebuffer.h>

#include "tilcdc_drv.h"

static const struct drm_plane_funcs tilcdc_plane_funcs = {
        .update_plane   = drm_atomic_helper_update_plane,
        .disable_plane  = drm_atomic_helper_disable_plane,
        .destroy        = drm_plane_cleanup,
        .reset          = drm_atomic_helper_plane_reset,
        .atomic_duplicate_state = drm_atomic_helper_plane_duplicate_state,
        .atomic_destroy_state = drm_atomic_helper_plane_destroy_state,
};

static int tilcdc_plane_atomic_check(struct drm_plane *plane,
                                     struct drm_atomic_state *state)
{
        struct drm_plane_state *new_state = drm_atomic_get_new_plane_state(state,
                                                                           plane);
        struct drm_crtc_state *crtc_state;
        struct drm_plane_state *old_state = drm_atomic_get_old_plane_state(state,
                                                                           plane);
        unsigned int pitch;

        if (!new_state->crtc)
                return 0;

        if (WARN_ON(!new_state->fb))
                return -EINVAL;

        if (new_state->crtc_x || new_state->crtc_y) {
                dev_err(plane->dev->dev, "%s: crtc position must be zero.",
                        __func__);
                return -EINVAL;
        }

        crtc_state = drm_atomic_get_new_crtc_state(state, new_state->crtc);
        /* we should have a crtc state if the plane is attached to a crtc */
        if (WARN_ON(!crtc_state))
                return 0;

        if (crtc_state->mode.hdisplay != new_state->crtc_w ||
            crtc_state->mode.vdisplay != new_state->crtc_h) {
                dev_err(plane->dev->dev,
                        "%s: Size must match mode (%dx%d == %dx%d)", __func__,
                        crtc_state->mode.hdisplay, crtc_state->mode.vdisplay,
                        new_state->crtc_w, new_state->crtc_h);
                return -EINVAL;
        }

        pitch = crtc_state->mode.hdisplay *
                new_state->fb->format->cpp[0];
        if (new_state->fb->pitches[0] != pitch) {
                dev_err(plane->dev->dev,
                        "Invalid pitch: fb and crtc widths must be the same");
                return -EINVAL;
        }

        if (old_state->fb && new_state->fb->format != old_state->fb->format) {
                dev_dbg(plane->dev->dev,
                        "%s(): pixel format change requires mode_change\n",
                        __func__);
                crtc_state->mode_changed = true;
        }

        return 0;
}

static void tilcdc_plane_atomic_update(struct drm_plane *plane,
                                       struct drm_atomic_state *state)
{
        struct drm_plane_state *new_state = drm_atomic_get_new_plane_state(state,
                                                                           plane);

        if (!new_state->crtc)
                return;

        if (WARN_ON(!new_state->fb || !new_state->crtc->state))
                return;

        if (tilcdc_crtc_update_fb(new_state->crtc,
                                  new_state->fb,
                                  new_state->crtc->state->event) == 0) {
                new_state->crtc->state->event = NULL;
        }
}

static const struct drm_plane_helper_funcs plane_helper_funcs = {
        .atomic_check = tilcdc_plane_atomic_check,
        .atomic_update = tilcdc_plane_atomic_update,
};

int tilcdc_plane_init(struct drm_device *dev,
                      struct drm_plane *plane)
{
        struct tilcdc_drm_private *priv = dev->dev_private;
        int ret;

        ret = drm_universal_plane_init(dev, plane, 1, &tilcdc_plane_funcs,
                                       priv->pixelformats,
                                       priv->num_pixelformats,
                                       NULL, DRM_PLANE_TYPE_PRIMARY, NULL);
        if (ret) {
                dev_err(dev->dev, "Failed to initialize plane: %d\n", ret);
                return ret;
        }

        drm_plane_helper_add(plane, &plane_helper_funcs);

        return 0;
}