/*
 * Copyright (C) 2013 Red Hat
 * Author: Rob Clark <robdclark@gmail.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.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include "msm_drv.h"

#include "drm_crtc.h"
#include "drm_crtc_helper.h"

struct msm_framebuffer {
        struct drm_framebuffer base;
        const struct msm_format *format;
        struct drm_gem_object *planes[2];
};
#define to_msm_framebuffer(x) container_of(x, struct msm_framebuffer, base)


static int msm_framebuffer_create_handle(struct drm_framebuffer *fb,
                struct drm_file *file_priv,
                unsigned int *handle)
{
        struct msm_framebuffer *msm_fb = to_msm_framebuffer(fb);
        return drm_gem_handle_create(file_priv,
                        msm_fb->planes[0], handle);
}

static void msm_framebuffer_destroy(struct drm_framebuffer *fb)
{
        struct msm_framebuffer *msm_fb = to_msm_framebuffer(fb);
        int i, n = drm_format_num_planes(fb->pixel_format);

        DBG("destroy: FB ID: %d (%p)", fb->base.id, fb);

        drm_framebuffer_cleanup(fb);

        for (i = 0; i < n; i++) {
                struct drm_gem_object *bo = msm_fb->planes[i];
                if (bo)
                        drm_gem_object_unreference_unlocked(bo);
        }

        kfree(msm_fb);
}

static int msm_framebuffer_dirty(struct drm_framebuffer *fb,
                struct drm_file *file_priv, unsigned flags, unsigned color,
                struct drm_clip_rect *clips, unsigned num_clips)
{
        return 0;
}

static const struct drm_framebuffer_funcs msm_framebuffer_funcs = {
        .create_handle = msm_framebuffer_create_handle,
        .destroy = msm_framebuffer_destroy,
        .dirty = msm_framebuffer_dirty,
};

#ifdef CONFIG_DEBUG_FS
void msm_framebuffer_describe(struct drm_framebuffer *fb, struct seq_file *m)
{
        struct msm_framebuffer *msm_fb = to_msm_framebuffer(fb);
        int i, n = drm_format_num_planes(fb->pixel_format);

        seq_printf(m, "fb: %dx%d@%4.4s (%2d, ID:%d)\n",
                        fb->width, fb->height, (char *)&fb->pixel_format,
                        fb->refcount.refcount.counter, fb->base.id);

        for (i = 0; i < n; i++) {
                seq_printf(m, "   %d: offset=%d pitch=%d, obj: ",
                                i, fb->offsets[i], fb->pitches[i]);
                msm_gem_describe(msm_fb->planes[i], m);
        }
}
#endif

struct drm_gem_object *msm_framebuffer_bo(struct drm_framebuffer *fb, int plane)
{
        struct msm_framebuffer *msm_fb = to_msm_framebuffer(fb);
        return msm_fb->planes[plane];
}

const struct msm_format *msm_framebuffer_format(struct drm_framebuffer *fb)
{
        struct msm_framebuffer *msm_fb = to_msm_framebuffer(fb);
        return msm_fb->format;
}

struct drm_framebuffer *msm_framebuffer_create(struct drm_device *dev,
                struct drm_file *file, struct drm_mode_fb_cmd2 *mode_cmd)
{
        struct drm_gem_object *bos[4] = {0};
        struct drm_framebuffer *fb;
        int ret, i, n = drm_format_num_planes(mode_cmd->pixel_format);

        for (i = 0; i < n; i++) {
                bos[i] = drm_gem_object_lookup(dev, file,
                                mode_cmd->handles[i]);
                if (!bos[i]) {
                        ret = -ENXIO;
                        goto out_unref;
                }
        }

        fb = msm_framebuffer_init(dev, mode_cmd, bos);
        if (IS_ERR(fb)) {
                ret = PTR_ERR(fb);
                goto out_unref;
        }

        return fb;

out_unref:
        for (i = 0; i < n; i++)
                drm_gem_object_unreference_unlocked(bos[i]);
        return ERR_PTR(ret);
}

struct drm_framebuffer *msm_framebuffer_init(struct drm_device *dev,
                struct drm_mode_fb_cmd2 *mode_cmd, struct drm_gem_object **bos)
{
        struct msm_drm_private *priv = dev->dev_private;
        struct msm_kms *kms = priv->kms;
        struct msm_framebuffer *msm_fb;
        struct drm_framebuffer *fb = NULL;
        const struct msm_format *format;
        int ret, i, n;
        unsigned int hsub, vsub;

        DBG("create framebuffer: dev=%p, mode_cmd=%p (%dx%d@%4.4s)",
                        dev, mode_cmd, mode_cmd->width, mode_cmd->height,
                        (char *)&mode_cmd->pixel_format);

        n = drm_format_num_planes(mode_cmd->pixel_format);
        hsub = drm_format_horz_chroma_subsampling(mode_cmd->pixel_format);
        vsub = drm_format_vert_chroma_subsampling(mode_cmd->pixel_format);

        format = kms->funcs->get_format(kms, mode_cmd->pixel_format);
        if (!format) {
                dev_err(dev->dev, "unsupported pixel format: %4.4s\n",
                                (char *)&mode_cmd->pixel_format);
                ret = -EINVAL;
                goto fail;
        }

        msm_fb = kzalloc(sizeof(*msm_fb), GFP_KERNEL);
        if (!msm_fb) {
                ret = -ENOMEM;
                goto fail;
        }

        fb = &msm_fb->base;

        msm_fb->format = format;

        for (i = 0; i < n; i++) {
                unsigned int width = mode_cmd->width / (i ? hsub : 1);
                unsigned int height = mode_cmd->height / (i ? vsub : 1);
                unsigned int min_size;

                min_size = (height - 1) * mode_cmd->pitches[i]
                         + width * drm_format_plane_cpp(mode_cmd->pixel_format, i)
                         + mode_cmd->offsets[i];

                if (bos[i]->size < min_size) {
                        ret = -EINVAL;
                        goto fail;
                }

                msm_fb->planes[i] = bos[i];
        }

        drm_helper_mode_fill_fb_struct(fb, mode_cmd);

        ret = drm_framebuffer_init(dev, fb, &msm_framebuffer_funcs);
        if (ret) {
                dev_err(dev->dev, "framebuffer init failed: %d\n", ret);
                goto fail;
        }

        DBG("create: FB ID: %d (%p)", fb->base.id, fb);

        return fb;

fail:
        if (fb)
                msm_framebuffer_destroy(fb);

        return ERR_PTR(ret);
}