/*

   *	linux/drivers/video/pmag-ba-fb.c

   *

   *	PMAG-BA TURBOchannel Color Frame Buffer (CFB) card support,
   *	derived from:

   *	"HP300 Topcat framebuffer support (derived from macfb of all things)
   *	Phil Blundell <philb@gnu.org> 1998", the original code can be

   *	found in the file hpfb.c in the same directory.

   *
   *	Based on digital document:
   * 	"PMAG-BA TURBOchannel Color Frame Buffer
   *	 Functional Specification", Revision 1.2, August 27, 1990
   *

   *	DECstation related code Copyright (C) 1999, 2000, 2001 by
   *	Michael Engel <engel@unix-ag.org>,
   *	Karsten Merker <merker@linuxtag.org> and

   *	Harald Koerfgen.

   *	Copyright (c) 2005, 2006  Maciej W. Rozycki
   *	Copyright (c) 2005  James Simmons

   *

   *	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.

   */

  
  #include <linux/compiler.h>

  #include <linux/errno.h>

  #include <linux/fb.h>

  #include <linux/init.h>
  #include <linux/kernel.h>
  #include <linux/module.h>

  #include <linux/tc.h>

  #include <linux/types.h>

  #include <asm/io.h>
  #include <asm/system.h>

  #include <video/pmag-ba-fb.h>

  
  struct pmagbafb_par {

  	volatile void __iomem *mmio;
  	volatile u32 __iomem *dac;

  };

  static struct fb_var_screeninfo pmagbafb_defined __devinitdata = {

  	.xres		= 1024,
  	.yres		= 864,
  	.xres_virtual	= 1024,
  	.yres_virtual	= 864,
  	.bits_per_pixel	= 8,
  	.red.length	= 8,
  	.green.length	= 8,
  	.blue.length	= 8,
  	.activate	= FB_ACTIVATE_NOW,

  	.height		= -1,
  	.width		= -1,
  	.accel_flags	= FB_ACCEL_NONE,
  	.pixclock	= 14452,
  	.left_margin	= 116,
  	.right_margin	= 12,
  	.upper_margin	= 34,
  	.lower_margin	= 12,
  	.hsync_len	= 128,
  	.vsync_len	= 3,
  	.sync		= FB_SYNC_ON_GREEN,

  	.vmode		= FB_VMODE_NONINTERLACED,
  };

  static struct fb_fix_screeninfo pmagbafb_fix __devinitdata = {

  	.id		= "PMAG-BA",

  	.smem_len	= (1024 * 1024),

  	.type		= FB_TYPE_PACKED_PIXELS,
  	.visual		= FB_VISUAL_PSEUDOCOLOR,
  	.line_length	= 1024,

  	.mmio_len	= PMAG_BA_SIZE - PMAG_BA_BT459,

  };

  
  static inline void dac_write(struct pmagbafb_par *par, unsigned int reg, u8 v)

  {

  	writeb(v, par->dac + reg / 4);

  }

  static inline u8 dac_read(struct pmagbafb_par *par, unsigned int reg)
  {
  	return readb(par->dac + reg / 4);
  }

  /*

   * Set the palette.

   */

  static int pmagbafb_setcolreg(unsigned int regno, unsigned int red,
  			      unsigned int green, unsigned int blue,
  			      unsigned int transp, struct fb_info *info)

  {

  	struct pmagbafb_par *par = info->par;

  	if (regno >= info->cmap.len)
  		return 1;

  
  	red   >>= 8;	/* The cmap fields are 16 bits    */

  	green >>= 8;	/* wide, but the hardware colormap */

  	blue  >>= 8;	/* registers are only 8 bits wide */

  	mb();
  	dac_write(par, BT459_ADDR_LO, regno);
  	dac_write(par, BT459_ADDR_HI, 0x00);
  	wmb();
  	dac_write(par, BT459_CMAP, red);
  	wmb();
  	dac_write(par, BT459_CMAP, green);
  	wmb();
  	dac_write(par, BT459_CMAP, blue);

  	return 0;
  }
  
  static struct fb_ops pmagbafb_ops = {
  	.owner		= THIS_MODULE,

  	.fb_setcolreg	= pmagbafb_setcolreg,
  	.fb_fillrect	= cfb_fillrect,
  	.fb_copyarea	= cfb_copyarea,
  	.fb_imageblit	= cfb_imageblit,

  };

  
  /*
   * Turn the hardware cursor off.
   */
  static void __init pmagbafb_erase_cursor(struct fb_info *info)
  {
  	struct pmagbafb_par *par = info->par;
  
  	mb();
  	dac_write(par, BT459_ADDR_LO, 0x00);
  	dac_write(par, BT459_ADDR_HI, 0x03);
  	wmb();
  	dac_write(par, BT459_DATA, 0x00);
  }

  static int __devinit pmagbafb_probe(struct device *dev)

  {

  	struct tc_dev *tdev = to_tc_dev(dev);
  	resource_size_t start, len;

  	struct fb_info *info;
  	struct pmagbafb_par *par;

  	int err;

  	info = framebuffer_alloc(sizeof(struct pmagbafb_par), dev);

  	if (!info) {

  		printk(KERN_ERR "%s: Cannot allocate memory
  ", dev_name(dev));

  		return -ENOMEM;

  	}

  
  	par = info->par;

  	dev_set_drvdata(dev, info);

  	if (fb_alloc_cmap(&info->cmap, 256, 0) < 0) {
  		printk(KERN_ERR "%s: Cannot allocate color map
  ",

  		       dev_name(dev));

  		err = -ENOMEM;

  		goto err_alloc;

  	}

  	info->fbops = &pmagbafb_ops;

  	info->fix = pmagbafb_fix;

  	info->var = pmagbafb_defined;

  	info->flags = FBINFO_DEFAULT;

  	/* 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
  ",
  		       dev_name(dev));

  		err = -EBUSY;

  		goto err_cmap;

  	}

  	/* MMIO mapping setup.  */

  	info->fix.mmio_start = start;

  	par->mmio = ioremap_nocache(info->fix.mmio_start, info->fix.mmio_len);

  	if (!par->mmio) {

  		printk(KERN_ERR "%s: Cannot map MMIO
  ", dev_name(dev));

  		err = -ENOMEM;

  		goto err_resource;

  	}

  	par->dac = par->mmio + PMAG_BA_BT459;
  
  	/* Frame buffer mapping setup.  */

  	info->fix.smem_start = start + PMAG_BA_FBMEM;

  	info->screen_base = ioremap_nocache(info->fix.smem_start,
  					    info->fix.smem_len);

  	if (!info->screen_base) {

  		printk(KERN_ERR "%s: Cannot map FB
  ", dev_name(dev));

  		err = -ENOMEM;

  		goto err_mmio_map;

  	}

  	info->screen_size = info->fix.smem_len;
  
  	pmagbafb_erase_cursor(info);

  	err = register_framebuffer(info);
  	if (err < 0) {
  		printk(KERN_ERR "%s: Cannot register framebuffer
  ",

  		       dev_name(dev));

  		goto err_smem_map;

  	}

  	get_device(dev);
  
  	pr_info("fb%d: %s frame buffer device at %s
  ",

  		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_cmap:
  	fb_dealloc_cmap(&info->cmap);
  
  err_alloc:

  	framebuffer_release(info);

  	return err;

  }

  static int __exit pmagbafb_remove(struct device *dev)

  {

  	struct tc_dev *tdev = to_tc_dev(dev);
  	struct fb_info *info = dev_get_drvdata(dev);

  	struct pmagbafb_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);

  	fb_dealloc_cmap(&info->cmap);

  	framebuffer_release(info);

  	return 0;

  }
  
  
  /*

   * Initialize the framebuffer.

   */

  static const struct tc_device_id pmagbafb_tc_table[] = {
  	{ "DEC     ", "PMAG-BA " },
  	{ }
  };
  MODULE_DEVICE_TABLE(tc, pmagbafb_tc_table);
  
  static struct tc_driver pmagbafb_driver = {
  	.id_table	= pmagbafb_tc_table,
  	.driver		= {
  		.name	= "pmagbafb",
  		.bus	= &tc_bus_type,
  		.probe	= pmagbafb_probe,
  		.remove	= __exit_p(pmagbafb_remove),
  	},
  };

  static int __init pmagbafb_init(void)

  {

  #ifndef MODULE

  	if (fb_get_options("pmagbafb", NULL))

  		return -ENXIO;

  #endif
  	return tc_register_driver(&pmagbafb_driver);

  }

  static void __exit pmagbafb_exit(void)
  {

  	tc_unregister_driver(&pmagbafb_driver);

  }

  module_init(pmagbafb_init);

  module_exit(pmagbafb_exit);

  MODULE_LICENSE("GPL");