// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2012 Russell King
 *  Written from the i915 driver.
 */

#include <linux/errno.h>
#include <linux/fb.h>
#include <linux/kernel.h>
#include <linux/module.h>

#include <drm/drm_crtc_helper.h>
#include <drm/drm_drv.h>
#include <drm/drm_fb_helper.h>
#include <drm/drm_fourcc.h>
#include <drm/drm_print.h>

#include "armada_crtc.h"
#include "armada_drm.h"
#include "armada_fb.h"
#include "armada_gem.h"

static void armada_fbdev_fb_destroy(struct fb_info *info)
{
        struct drm_fb_helper *fbh = info->par;

        drm_fb_helper_fini(fbh);

        fbh->fb->funcs->destroy(fbh->fb);

        drm_client_release(&fbh->client);
}

static const struct fb_ops armada_fb_ops = {
        .owner          = THIS_MODULE,
        FB_DEFAULT_IOMEM_OPS,
        DRM_FB_HELPER_DEFAULT_OPS,
        .fb_destroy     = armada_fbdev_fb_destroy,
};

static const struct drm_fb_helper_funcs armada_fbdev_helper_funcs;

int armada_fbdev_driver_fbdev_probe(struct drm_fb_helper *fbh,
                                    struct drm_fb_helper_surface_size *sizes)
{
        struct drm_device *dev = fbh->dev;
        struct fb_info *info = fbh->info;
        struct drm_mode_fb_cmd2 mode;
        struct armada_framebuffer *dfb;
        struct armada_gem_object *obj;
        int size, ret;
        void *ptr;

        memset(&mode, 0, sizeof(mode));
        mode.width = sizes->surface_width;
        mode.height = sizes->surface_height;
        mode.pitches[0] = armada_pitch(mode.width, sizes->surface_bpp);
        mode.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp,
                                        sizes->surface_depth);

        size = mode.pitches[0] * mode.height;
        obj = armada_gem_alloc_private_object(dev, size);
        if (!obj) {
                DRM_ERROR("failed to allocate fb memory\n");
                return -ENOMEM;
        }

        ret = armada_gem_linear_back(dev, obj);
        if (ret) {
                drm_gem_object_put(&obj->obj);
                return ret;
        }

        ptr = armada_gem_map_object(dev, obj);
        if (!ptr) {
                drm_gem_object_put(&obj->obj);
                return -ENOMEM;
        }

        dfb = armada_framebuffer_create(dev,
                                        drm_get_format_info(dev, mode.pixel_format,
                                                            mode.modifier[0]),
                                        &mode, obj);

        /*
         * A reference is now held by the framebuffer object if
         * successful, otherwise this drops the ref for the error path.
         */
        drm_gem_object_put(&obj->obj);

        if (IS_ERR(dfb))
                return PTR_ERR(dfb);

        info->fbops = &armada_fb_ops;
        info->fix.smem_start = obj->phys_addr;
        info->fix.smem_len = obj->obj.size;
        info->screen_size = obj->obj.size;
        info->screen_base = ptr;
        fbh->funcs = &armada_fbdev_helper_funcs;
        fbh->fb = &dfb->fb;

        drm_fb_helper_fill_info(info, fbh, sizes);

        DRM_DEBUG_KMS("allocated %dx%d %dbpp fb: 0x%08llx\n",
                dfb->fb.width, dfb->fb.height, dfb->fb.format->cpp[0] * 8,
                (unsigned long long)obj->phys_addr);

        return 0;
}