/* bw2.c: BWTWO frame buffer driver
   *

   * Copyright (C) 2003, 2006 David S. Miller (davem@davemloft.net)

   * Copyright (C) 1996,1998 Jakub Jelinek (jj@ultra.linux.cz)
   * Copyright (C) 1996 Miguel de Icaza (miguel@nuclecu.unam.mx)
   * Copyright (C) 1997 Eddie C. Dost (ecd@skynet.be)
   *
   * Driver layout based loosely on tgafb.c, see that file for credits.
   */
  
  #include <linux/module.h>
  #include <linux/kernel.h>
  #include <linux/errno.h>
  #include <linux/string.h>

  #include <linux/delay.h>
  #include <linux/init.h>
  #include <linux/fb.h>
  #include <linux/mm.h>

  #include <linux/of_device.h>

  
  #include <asm/io.h>

  #include <asm/fbio.h>

  #include "sbuslib.h"
  
  /*
   * Local functions.
   */
  
  static int bw2_blank(int, struct fb_info *);

  static int bw2_mmap(struct fb_info *, struct vm_area_struct *);

  static int bw2_ioctl(struct fb_info *, unsigned int, unsigned long);

  
  /*
   *  Frame buffer operations
   */
  
  static struct fb_ops bw2_ops = {
  	.owner			= THIS_MODULE,
  	.fb_blank		= bw2_blank,
  	.fb_fillrect		= cfb_fillrect,
  	.fb_copyarea		= cfb_copyarea,
  	.fb_imageblit		= cfb_imageblit,
  	.fb_mmap		= bw2_mmap,
  	.fb_ioctl		= bw2_ioctl,

  #ifdef CONFIG_COMPAT
  	.fb_compat_ioctl	= sbusfb_compat_ioctl,
  #endif

  };
  
  /* OBio addresses for the bwtwo registers */
  #define BWTWO_REGISTER_OFFSET 0x400000
  
  struct bt_regs {

  	u32 addr;
  	u32 color_map;
  	u32 control;
  	u32 cursor;

  };
  
  struct bw2_regs {
  	struct bt_regs	cmap;

  	u8	control;
  	u8	status;
  	u8	cursor_start;
  	u8	cursor_end;
  	u8	h_blank_start;
  	u8	h_blank_end;
  	u8	h_sync_start;
  	u8	h_sync_end;
  	u8	comp_sync_end;
  	u8	v_blank_start_high;
  	u8	v_blank_start_low;
  	u8	v_blank_end;
  	u8	v_sync_start;
  	u8	v_sync_end;
  	u8	xfer_holdoff_start;
  	u8	xfer_holdoff_end;

  };
  
  /* Status Register Constants */
  #define BWTWO_SR_RES_MASK	0x70
  #define BWTWO_SR_1600_1280	0x50
  #define BWTWO_SR_1152_900_76_A	0x40
  #define BWTWO_SR_1152_900_76_B	0x60
  #define BWTWO_SR_ID_MASK	0x0f
  #define BWTWO_SR_ID_MONO	0x02
  #define BWTWO_SR_ID_MONO_ECL	0x03
  #define BWTWO_SR_ID_MSYNC	0x04
  #define BWTWO_SR_ID_NOCONN	0x0a
  
  /* Control Register Constants */
  #define BWTWO_CTL_ENABLE_INTS   0x80
  #define BWTWO_CTL_ENABLE_VIDEO  0x40
  #define BWTWO_CTL_ENABLE_TIMING 0x20
  #define BWTWO_CTL_ENABLE_CURCMP 0x10
  #define BWTWO_CTL_XTAL_MASK     0x0C
  #define BWTWO_CTL_DIVISOR_MASK  0x03
  
  /* Status Register Constants */
  #define BWTWO_STAT_PENDING_INT  0x80
  #define BWTWO_STAT_MSENSE_MASK  0x70
  #define BWTWO_STAT_ID_MASK      0x0f
  
  struct bw2_par {
  	spinlock_t		lock;
  	struct bw2_regs		__iomem *regs;
  
  	u32			flags;
  #define BW2_FLAG_BLANKED	0x00000001

  	unsigned long		which_io;

  };
  
  /**
   *      bw2_blank - Optional function.  Blanks the display.
   *      @blank_mode: the blank mode we want.
   *      @info: frame buffer structure that represents a single frame buffer
   */
  static int
  bw2_blank(int blank, struct fb_info *info)
  {
  	struct bw2_par *par = (struct bw2_par *) info->par;
  	struct bw2_regs __iomem *regs = par->regs;
  	unsigned long flags;
  	u8 val;
  
  	spin_lock_irqsave(&par->lock, flags);
  
  	switch (blank) {
  	case FB_BLANK_UNBLANK: /* Unblanking */
  		val = sbus_readb(&regs->control);
  		val |= BWTWO_CTL_ENABLE_VIDEO;
  		sbus_writeb(val, &regs->control);
  		par->flags &= ~BW2_FLAG_BLANKED;
  		break;
  
  	case FB_BLANK_NORMAL: /* Normal blanking */
  	case FB_BLANK_VSYNC_SUSPEND: /* VESA blank (vsync off) */
  	case FB_BLANK_HSYNC_SUSPEND: /* VESA blank (hsync off) */
  	case FB_BLANK_POWERDOWN: /* Poweroff */
  		val = sbus_readb(&regs->control);
  		val &= ~BWTWO_CTL_ENABLE_VIDEO;
  		sbus_writeb(val, &regs->control);
  		par->flags |= BW2_FLAG_BLANKED;
  		break;
  	}
  
  	spin_unlock_irqrestore(&par->lock, flags);
  
  	return 0;
  }
  
  static struct sbus_mmap_map bw2_mmap_map[] = {
  	{
  		.size = SBUS_MMAP_FBSIZE(1)
  	},
  	{ .size = 0 }
  };

  static int bw2_mmap(struct fb_info *info, struct vm_area_struct *vma)

  {
  	struct bw2_par *par = (struct bw2_par *)info->par;
  
  	return sbusfb_mmap_helper(bw2_mmap_map,

  				  info->fix.smem_start, info->fix.smem_len,

  				  par->which_io,

  				  vma);
  }

  static int bw2_ioctl(struct fb_info *info, unsigned int cmd, unsigned long arg)

  {

  	return sbusfb_ioctl_helper(cmd, arg, info,

  				   FBTYPE_SUN2BW, 1, info->fix.smem_len);

  }
  
  /*
   *  Initialisation
   */

  static void __devinit bw2_init_fix(struct fb_info *info, int linebytes)

  {
  	strlcpy(info->fix.id, "bwtwo", sizeof(info->fix.id));
  
  	info->fix.type = FB_TYPE_PACKED_PIXELS;
  	info->fix.visual = FB_VISUAL_MONO01;
  
  	info->fix.line_length = linebytes;
  
  	info->fix.accel = FB_ACCEL_SUN_BWTWO;
  }

  static u8 bw2regs_1600[] __devinitdata = {

  	0x14, 0x8b,	0x15, 0x28,	0x16, 0x03,	0x17, 0x13,
  	0x18, 0x7b,	0x19, 0x05,	0x1a, 0x34,	0x1b, 0x2e,
  	0x1c, 0x00,	0x1d, 0x0a,	0x1e, 0xff,	0x1f, 0x01,
  	0x10, 0x21,	0
  };

  static u8 bw2regs_ecl[] __devinitdata = {

  	0x14, 0x65,	0x15, 0x1e,	0x16, 0x04,	0x17, 0x0c,
  	0x18, 0x5e,	0x19, 0x03,	0x1a, 0xa7,	0x1b, 0x23,
  	0x1c, 0x00,	0x1d, 0x08,	0x1e, 0xff,	0x1f, 0x01,
  	0x10, 0x20,	0
  };

  static u8 bw2regs_analog[] __devinitdata = {

  	0x14, 0xbb,	0x15, 0x2b,	0x16, 0x03,	0x17, 0x13,
  	0x18, 0xb0,	0x19, 0x03,	0x1a, 0xa6,	0x1b, 0x22,
  	0x1c, 0x01,	0x1d, 0x05,	0x1e, 0xff,	0x1f, 0x01,
  	0x10, 0x20,	0
  };

  static u8 bw2regs_76hz[] __devinitdata = {

  	0x14, 0xb7,	0x15, 0x27,	0x16, 0x03,	0x17, 0x0f,
  	0x18, 0xae,	0x19, 0x03,	0x1a, 0xae,	0x1b, 0x2a,
  	0x1c, 0x01,	0x1d, 0x09,	0x1e, 0xff,	0x1f, 0x01,
  	0x10, 0x24,	0
  };

  static u8 bw2regs_66hz[] __devinitdata = {

  	0x14, 0xbb,	0x15, 0x2b,	0x16, 0x04,	0x17, 0x14,
  	0x18, 0xae,	0x19, 0x03,	0x1a, 0xa8,	0x1b, 0x24,
  	0x1c, 0x01,	0x1d, 0x05,	0x1e, 0xff,	0x1f, 0x01,
  	0x10, 0x20,	0
  };

  static int __devinit bw2_do_default_mode(struct bw2_par *par,
  					 struct fb_info *info,
  					 int *linebytes)

  {
  	u8 status, mon;
  	u8 *p;
  
  	status = sbus_readb(&par->regs->status);
  	mon = status & BWTWO_SR_RES_MASK;
  	switch (status & BWTWO_SR_ID_MASK) {
  	case BWTWO_SR_ID_MONO_ECL:
  		if (mon == BWTWO_SR_1600_1280) {
  			p = bw2regs_1600;
  			info->var.xres = info->var.xres_virtual = 1600;
  			info->var.yres = info->var.yres_virtual = 1280;
  			*linebytes = 1600 / 8;
  		} else
  			p = bw2regs_ecl;
  		break;
  
  	case BWTWO_SR_ID_MONO:
  		p = bw2regs_analog;
  		break;
  
  	case BWTWO_SR_ID_MSYNC:
  		if (mon == BWTWO_SR_1152_900_76_A ||
  		    mon == BWTWO_SR_1152_900_76_B)
  			p = bw2regs_76hz;
  		else
  			p = bw2regs_66hz;
  		break;
  
  	case BWTWO_SR_ID_NOCONN:

  		return 0;

  
  	default:

  		printk(KERN_ERR "bw2: can't handle SR %02x
  ",
  		       status);
  		return -EINVAL;

  	}
  	for ( ; *p; p += 2) {
  		u8 __iomem *regp = &((u8 __iomem *)par->regs)[p[0]];
  		sbus_writeb(p[1], regp);
  	}

  	return 0;

  }

  static int __devinit bw2_probe(struct platform_device *op)

  {

  	struct device_node *dp = op->dev.of_node;

  	struct fb_info *info;
  	struct bw2_par *par;

  	int linebytes, err;

  	info = framebuffer_alloc(sizeof(struct bw2_par), &op->dev);

  	err = -ENOMEM;
  	if (!info)
  		goto out_err;
  	par = info->par;

  	spin_lock_init(&par->lock);

  	info->fix.smem_start = op->resource[0].start;

  	par->which_io = op->resource[0].flags & IORESOURCE_BITS;

  	sbusfb_fill_var(&info->var, dp, 1);

  	linebytes = of_getintprop_default(dp, "linebytes",

  					  info->var.xres);

  	info->var.red.length = info->var.green.length =
  		info->var.blue.length = info->var.bits_per_pixel;
  	info->var.red.offset = info->var.green.offset =
  		info->var.blue.offset = 0;

  	par->regs = of_ioremap(&op->resource[0], BWTWO_REGISTER_OFFSET,
  			       sizeof(struct bw2_regs), "bw2 regs");
  	if (!par->regs)
  		goto out_release_fb;

  	if (!of_find_property(dp, "width", NULL)) {
  		err = bw2_do_default_mode(par, info, &linebytes);
  		if (err)
  			goto out_unmap_regs;
  	}

  	info->fix.smem_len = PAGE_ALIGN(linebytes * info->var.yres);

  	info->flags = FBINFO_DEFAULT;
  	info->fbops = &bw2_ops;

  	info->screen_base = of_ioremap(&op->resource[0], 0,

  				       info->fix.smem_len, "bw2 ram");

  	if (!info->screen_base)
  		goto out_unmap_regs;

  	bw2_blank(FB_BLANK_UNBLANK, info);

  	bw2_init_fix(info, linebytes);

  	err = register_framebuffer(info);
  	if (err < 0)
  		goto out_unmap_screen;

  	dev_set_drvdata(&op->dev, info);

  	printk(KERN_INFO "%s: bwtwo at %lx:%lx
  ",

  	       dp->full_name, par->which_io, info->fix.smem_start);

  	return 0;

  out_unmap_screen:

  	of_iounmap(&op->resource[0], info->screen_base, info->fix.smem_len);

  
  out_unmap_regs:
  	of_iounmap(&op->resource[0], par->regs, sizeof(struct bw2_regs));
  
  out_release_fb:
  	framebuffer_release(info);

  out_err:
  	return err;

  }

  static int __devexit bw2_remove(struct platform_device *op)

  {

  	struct fb_info *info = dev_get_drvdata(&op->dev);
  	struct bw2_par *par = info->par;

  	unregister_framebuffer(info);

  	of_iounmap(&op->resource[0], par->regs, sizeof(struct bw2_regs));

  	of_iounmap(&op->resource[0], info->screen_base, info->fix.smem_len);

  	framebuffer_release(info);

  	dev_set_drvdata(&op->dev, NULL);

  
  	return 0;
  }

  static const struct of_device_id bw2_match[] = {

  	{
  		.name = "bwtwo",
  	},
  	{},
  };
  MODULE_DEVICE_TABLE(of, bw2_match);

  static struct platform_driver bw2_driver = {

  	.driver = {
  		.name = "bw2",
  		.owner = THIS_MODULE,
  		.of_match_table = bw2_match,
  	},

  	.probe		= bw2_probe,
  	.remove		= __devexit_p(bw2_remove),
  };

  static int __init bw2_init(void)
  {
  	if (fb_get_options("bw2fb", NULL))
  		return -ENODEV;

  	return platform_driver_register(&bw2_driver);

  }

  static void __exit bw2_exit(void)

  {

  	platform_driver_unregister(&bw2_driver);

  }

  module_init(bw2_init);

  module_exit(bw2_exit);

  
  MODULE_DESCRIPTION("framebuffer driver for BWTWO chipsets");

  MODULE_AUTHOR("David S. Miller <davem@davemloft.net>");
  MODULE_VERSION("2.0");

  MODULE_LICENSE("GPL");