/*
 *      linux/drivers/video/pmag-aa-fb.c
 *      Copyright 2002 Karsten Merker <merker@debian.org>
 *
 *      PMAG-AA TurboChannel framebuffer card support ... derived from
 *      pmag-ba-fb.c, which is Copyright (C) 1999, 2000, 2001 by
 *      Michael Engel <engel@unix-ag.org>, Karsten Merker <merker@debian.org>
 *      and Harald Koerfgen <hkoerfg@web.de>, which itself is derived from
 *      "HP300 Topcat framebuffer support (derived from macfb of all things)
 *      Phil Blundell <philb@gnu.org> 1998"
 *      Copyright (c) 2016  Maciej W. Rozycki
 *
 *      This file is subject to the terms and conditions of the GNU General
 *      Public License.  See the file COPYING in the main directory of this
 *      archive for more details.
 *
 *      2002-09-28  Karsten Merker <merker@linuxtag.org>
 *              Version 0.01: First try to get a PMAG-AA running.
 *
 *      2003-02-24  Thiemo Seufer  <seufer@csv.ica.uni-stuttgart.de>
 *              Version 0.02: Major code cleanup.
 *
 *      2003-09-21  Thiemo Seufer  <seufer@csv.ica.uni-stuttgart.de>
 *              Hardware cursor support.
 *
 *      2016-02-21  Maciej W. Rozycki  <macro@linux-mips.org>
 *              Version 0.03: Rewritten for the new FB and TC APIs.
 */

#include <linux/compiler.h>
#include <linux/errno.h>
#include <linux/fb.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/tc.h>
#include <linux/timer.h>

#include "bt455.h"
#include "bt431.h"

/* Version information */
#define DRIVER_VERSION "0.03"
#define DRIVER_AUTHOR "Karsten Merker <merker@linuxtag.org>"
#define DRIVER_DESCRIPTION "PMAG-AA Framebuffer Driver"

/*
 * Bt455 RAM DAC register base offset (rel. to TC slot base address).
 */
#define PMAG_AA_BT455_OFFSET            0x100000

/*
 * Bt431 cursor generator offset (rel. to TC slot base address).
 */
#define PMAG_AA_BT431_OFFSET            0x180000

/*
 * Begin of PMAG-AA framebuffer memory relative to TC slot address,
 * resolution is 1280x1024x1 (8 bits deep, but only LSB is used).
 */
#define PMAG_AA_ONBOARD_FBMEM_OFFSET    0x200000

struct aafb_par {
        void __iomem *mmio;
        struct bt455_regs __iomem *bt455;
        struct bt431_regs __iomem *bt431;
};

static const struct fb_var_screeninfo aafb_defined = {
        .xres           = 1280,
        .yres           = 1024,
        .xres_virtual   = 2048,
        .yres_virtual   = 1024,
        .bits_per_pixel = 8,
        .grayscale      = 1,
        .red.length     = 0,
        .green.length   = 1,
        .blue.length    = 0,
        .activate       = FB_ACTIVATE_NOW,
        .accel_flags    = FB_ACCEL_NONE,
        .pixclock       = 7645,
        .left_margin    = 224,
        .right_margin   = 32,
        .upper_margin   = 33,
        .lower_margin   = 3,
        .hsync_len      = 160,
        .vsync_len      = 3,
        .sync           = FB_SYNC_ON_GREEN,
        .vmode          = FB_VMODE_NONINTERLACED,
};

static const struct fb_fix_screeninfo aafb_fix = {
        .id             = "PMAG-AA",
        .smem_len       = (2048 * 1024),
        .type           = FB_TYPE_PACKED_PIXELS,
        .visual         = FB_VISUAL_MONO10,
        .ypanstep       = 1,
        .ywrapstep      = 1,
        .line_length    = 2048,
        .mmio_len       = PMAG_AA_ONBOARD_FBMEM_OFFSET - PMAG_AA_BT455_OFFSET,
};

static int aafb_cursor(struct fb_info *info, struct fb_cursor *cursor)
{
        struct aafb_par *par = info->par;

        if (cursor->image.height > BT431_CURSOR_SIZE ||
            cursor->image.width > BT431_CURSOR_SIZE) {
                bt431_erase_cursor(par->bt431);
                return -EINVAL;
        }

        if (!cursor->enable)
                bt431_erase_cursor(par->bt431);

        if (cursor->set & FB_CUR_SETPOS)
                bt431_position_cursor(par->bt431,
                                      cursor->image.dx, cursor->image.dy);
        if (cursor->set & FB_CUR_SETCMAP) {
                u8 fg = cursor->image.fg_color ? 0xf : 0x0;
                u8 bg = cursor->image.bg_color ? 0xf : 0x0;

                bt455_write_cmap_entry(par->bt455, 8, bg);
                bt455_write_cmap_next(par->bt455, bg);
                bt455_write_ovly_next(par->bt455, fg);
        }
        if (cursor->set & (FB_CUR_SETSIZE | FB_CUR_SETSHAPE | FB_CUR_SETIMAGE))
                bt431_set_cursor(par->bt431,
                                 cursor->image.data, cursor->mask, cursor->rop,
                                 cursor->image.width, cursor->image.height);

        if (cursor->enable)
                bt431_enable_cursor(par->bt431);

        return 0;
}

/* 0 unblanks, any other blanks. */

static int aafb_blank(int blank, struct fb_info *info)
{
        struct aafb_par *par = info->par;
        u8 val = blank ? 0x00 : 0x0f;

        bt455_write_cmap_entry(par->bt455, 1, val);
        return 0;
}

static const struct fb_ops aafb_ops = {
        .owner          = THIS_MODULE,
        FB_DEFAULT_IOMEM_OPS,
        .fb_blank       = aafb_blank,
        .fb_cursor      = aafb_cursor,
};

static int pmagaafb_probe(struct device *dev)
{
        struct tc_dev *tdev = to_tc_dev(dev);
        resource_size_t start, len;
        struct fb_info *info;
        struct aafb_par *par;
        int err;

        info = framebuffer_alloc(sizeof(struct aafb_par), dev);
        if (!info)
                return -ENOMEM;

        par = info->par;
        dev_set_drvdata(dev, info);

        info->fbops = &aafb_ops;
        info->fix = aafb_fix;
        info->var = aafb_defined;

        /* Request the I/O MEM resource. */
        start = tdev->resource.start;
        len = tdev->resource.end - start + 1;
        if (!request_mem_region(start, len, dev_name(dev))) {
                printk(KERN_ERR "%s: Cannot reserve FB region\n",
                       dev_name(dev));
                err = -EBUSY;
                goto err_alloc;
        }

        /* MMIO mapping setup. */
        info->fix.mmio_start = start + PMAG_AA_BT455_OFFSET;
        par->mmio = ioremap(info->fix.mmio_start, info->fix.mmio_len);
        if (!par->mmio) {
                printk(KERN_ERR "%s: Cannot map MMIO\n", dev_name(dev));
                err = -ENOMEM;
                goto err_resource;
        }
        par->bt455 = par->mmio - PMAG_AA_BT455_OFFSET + PMAG_AA_BT455_OFFSET;
        par->bt431 = par->mmio - PMAG_AA_BT455_OFFSET + PMAG_AA_BT431_OFFSET;

        /* Frame buffer mapping setup. */
        info->fix.smem_start = start + PMAG_AA_ONBOARD_FBMEM_OFFSET;
        info->screen_base = ioremap(info->fix.smem_start,
                                            info->fix.smem_len);
        if (!info->screen_base) {
                printk(KERN_ERR "%s: Cannot map FB\n", dev_name(dev));
                err = -ENOMEM;
                goto err_mmio_map;
        }
        info->screen_size = info->fix.smem_len;

        /* Init colormap. */
        bt455_write_cmap_entry(par->bt455, 0, 0x0);
        bt455_write_cmap_next(par->bt455, 0xf);

        /* Init hardware cursor. */
        bt431_erase_cursor(par->bt431);
        bt431_init_cursor(par->bt431);

        err = register_framebuffer(info);
        if (err < 0) {
                printk(KERN_ERR "%s: Cannot register framebuffer\n",
                       dev_name(dev));
                goto err_smem_map;
        }

        get_device(dev);

        pr_info("fb%d: %s frame buffer device at %s\n",
                info->node, info->fix.id, dev_name(dev));

        return 0;


err_smem_map:
        iounmap(info->screen_base);

err_mmio_map:
        iounmap(par->mmio);

err_resource:
        release_mem_region(start, len);

err_alloc:
        framebuffer_release(info);
        return err;
}

static int pmagaafb_remove(struct device *dev)
{
        struct tc_dev *tdev = to_tc_dev(dev);
        struct fb_info *info = dev_get_drvdata(dev);
        struct aafb_par *par = info->par;
        resource_size_t start, len;

        put_device(dev);
        unregister_framebuffer(info);
        iounmap(info->screen_base);
        iounmap(par->mmio);
        start = tdev->resource.start;
        len = tdev->resource.end - start + 1;
        release_mem_region(start, len);
        framebuffer_release(info);
        return 0;
}

/*
 * Initialise the framebuffer.
 */
static const struct tc_device_id pmagaafb_tc_table[] = {
        { "DEC     ", "PMAG-AA " },
        { }
};
MODULE_DEVICE_TABLE(tc, pmagaafb_tc_table);

static struct tc_driver pmagaafb_driver = {
        .id_table       = pmagaafb_tc_table,
        .driver         = {
                .name   = "pmagaafb",
                .bus    = &tc_bus_type,
                .probe  = pmagaafb_probe,
                .remove = pmagaafb_remove,
        },
};

static int __init pmagaafb_init(void)
{
#ifndef MODULE
        if (fb_get_options("pmagaafb", NULL))
                return -ENXIO;
#endif
        return tc_register_driver(&pmagaafb_driver);
}

static void __exit pmagaafb_exit(void)
{
        tc_unregister_driver(&pmagaafb_driver);
}

module_init(pmagaafb_init);
module_exit(pmagaafb_exit);

MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESCRIPTION);
MODULE_LICENSE("GPL");