[linux.git] / drivers / video / vfb.c

/*
 *  linux/drivers/video/vfb.c -- Virtual frame buffer device
 *
 *      Copyright (C) 2002 James Simmons
 *
 *	Copyright (C) 1997 Geert Uytterhoeven
 *
 *  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/module.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/tty.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>

#include <asm/uaccess.h>
#include <linux/fb.h>
#include <linux/init.h>

    /*
     *  RAM we reserve for the frame buffer. This defines the maximum screen
     *  size
     *
     *  The default can be overridden if the driver is compiled as a module
     */

#define VIDEOMEMSIZE	(1*1024*1024)	/* 1 MB */

static void *videomemory;
static u_long videomemorysize = VIDEOMEMSIZE;
module_param(videomemorysize, ulong, 0);

static struct fb_var_screeninfo vfb_default __initdata = {
	.xres =		640,
	.yres =		480,
	.xres_virtual =	640,
	.yres_virtual =	480,
	.bits_per_pixel = 8,
	.red =		{ 0, 8, 0 },
      	.green =	{ 0, 8, 0 },
      	.blue =		{ 0, 8, 0 },
      	.activate =	FB_ACTIVATE_TEST,
      	.height =	-1,
      	.width =	-1,
      	.pixclock =	20000,
      	.left_margin =	64,
      	.right_margin =	64,
      	.upper_margin =	32,
      	.lower_margin =	32,
      	.hsync_len =	64,
      	.vsync_len =	2,
      	.vmode =	FB_VMODE_NONINTERLACED,
};

static struct fb_fix_screeninfo vfb_fix __initdata = {
	.id =		"Virtual FB",
	.type =		FB_TYPE_PACKED_PIXELS,
	.visual =	FB_VISUAL_PSEUDOCOLOR,
	.xpanstep =	1,
	.ypanstep =	1,
	.ywrapstep =	1,
	.accel =	FB_ACCEL_NONE,
};

static int vfb_enable __initdata = 0;	/* disabled by default */
module_param(vfb_enable, bool, 0);

static int vfb_check_var(struct fb_var_screeninfo *var,
			 struct fb_info *info);
static int vfb_set_par(struct fb_info *info);
static int vfb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
			 u_int transp, struct fb_info *info);
static int vfb_pan_display(struct fb_var_screeninfo *var,
			   struct fb_info *info);
static int vfb_mmap(struct fb_info *info, struct file *file,
		    struct vm_area_struct *vma);

static struct fb_ops vfb_ops = {
	.fb_check_var	= vfb_check_var,
	.fb_set_par	= vfb_set_par,
	.fb_setcolreg	= vfb_setcolreg,
	.fb_pan_display	= vfb_pan_display,
	.fb_fillrect	= cfb_fillrect,
	.fb_copyarea	= cfb_copyarea,
	.fb_imageblit	= cfb_imageblit,
	.fb_mmap	= vfb_mmap,
};

    /*
     *  Internal routines
     */

static u_long get_line_length(int xres_virtual, int bpp)
{
	u_long length;

	length = xres_virtual * bpp;
	length = (length + 31) & ~31;
	length >>= 3;
	return (length);
}

    /*
     *  Setting the video mode has been split into two parts.
     *  First part, xxxfb_check_var, must not write anything
     *  to hardware, it should only verify and adjust var.
     *  This means it doesn't alter par but it does use hardware
     *  data from it to check this var. 
     */

static int vfb_check_var(struct fb_var_screeninfo *var,
			 struct fb_info *info)
{
	u_long line_length;

	/*
	 *  FB_VMODE_CONUPDATE and FB_VMODE_SMOOTH_XPAN are equal!
	 *  as FB_VMODE_SMOOTH_XPAN is only used internally
	 */

	if (var->vmode & FB_VMODE_CONUPDATE) {
		var->vmode |= FB_VMODE_YWRAP;
		var->xoffset = info->var.xoffset;
		var->yoffset = info->var.yoffset;
	}

	/*
	 *  Some very basic checks
	 */
	if (!var->xres)
		var->xres = 1;
	if (!var->yres)
		var->yres = 1;
	if (var->xres > var->xres_virtual)
		var->xres_virtual = var->xres;
	if (var->yres > var->yres_virtual)
		var->yres_virtual = var->yres;
	if (var->bits_per_pixel <= 1)
		var->bits_per_pixel = 1;
	else if (var->bits_per_pixel <= 8)
		var->bits_per_pixel = 8;
	else if (var->bits_per_pixel <= 16)
		var->bits_per_pixel = 16;
	else if (var->bits_per_pixel <= 24)
		var->bits_per_pixel = 24;
	else if (var->bits_per_pixel <= 32)
		var->bits_per_pixel = 32;
	else
		return -EINVAL;

	if (var->xres_virtual < var->xoffset + var->xres)
		var->xres_virtual = var->xoffset + var->xres;
	if (var->yres_virtual < var->yoffset + var->yres)
		var->yres_virtual = var->yoffset + var->yres;

	/*
	 *  Memory limit
	 */
	line_length =
	    get_line_length(var->xres_virtual, var->bits_per_pixel);
	if (line_length * var->yres_virtual > videomemorysize)
		return -ENOMEM;

	/*
	 * Now that we checked it we alter var. The reason being is that the video
	 * mode passed in might not work but slight changes to it might make it 
	 * work. This way we let the user know what is acceptable.
	 */
	switch (var->bits_per_pixel) {
	case 1:
	case 8:
		var->red.offset = 0;
		var->red.length = 8;
		var->green.offset = 0;
		var->green.length = 8;
		var->blue.offset = 0;
		var->blue.length = 8;
		var->transp.offset = 0;
		var->transp.length = 0;
		break;
	case 16:		/* RGBA 5551 */
		if (var->transp.length) {
			var->red.offset = 0;
			var->red.length = 5;
			var->green.offset = 5;
			var->green.length = 5;
			var->blue.offset = 10;
			var->blue.length = 5;
			var->transp.offset = 15;
			var->transp.length = 1;
		} else {	/* RGB 565 */
			var->red.offset = 0;
			var->red.length = 5;
			var->green.offset = 5;
			var->green.length = 6;
			var->blue.offset = 11;
			var->blue.length = 5;
			var->transp.offset = 0;
			var->transp.length = 0;
		}
		break;
	case 24:		/* RGB 888 */
		var->red.offset = 0;
		var->red.length = 8;
		var->green.offset = 8;
		var->green.length = 8;
		var->blue.offset = 16;
		var->blue.length = 8;
		var->transp.offset = 0;
		var->transp.length = 0;
		break;
	case 32:		/* RGBA 8888 */
		var->red.offset = 0;
		var->red.length = 8;
		var->green.offset = 8;
		var->green.length = 8;
		var->blue.offset = 16;
		var->blue.length = 8;
		var->transp.offset = 24;
		var->transp.length = 8;
		break;
	}
	var->red.msb_right = 0;
	var->green.msb_right = 0;
	var->blue.msb_right = 0;
	var->transp.msb_right = 0;

	return 0;
}

/* This routine actually sets the video mode. It's in here where we
 * the hardware state info->par and fix which can be affected by the 
 * change in par. For this driver it doesn't do much. 
 */
static int vfb_set_par(struct fb_info *info)
{
	info->fix.line_length = get_line_length(info->var.xres_virtual,
						info->var.bits_per_pixel);
	return 0;
}

    /*
     *  Set a single color register. The values supplied are already
     *  rounded down to the hardware's capabilities (according to the
     *  entries in the var structure). Return != 0 for invalid regno.
     */

static int vfb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
			 u_int transp, struct fb_info *info)
{
	if (regno >= 256)	/* no. of hw registers */
		return 1;
	/*
	 * Program hardware... do anything you want with transp
	 */

	/* grayscale works only partially under directcolor */
	if (info->var.grayscale) {
		/* grayscale = 0.30*R + 0.59*G + 0.11*B */
		red = green = blue =
		    (red * 77 + green * 151 + blue * 28) >> 8;
	}

	/* Directcolor:
	 *   var->{color}.offset contains start of bitfield
	 *   var->{color}.length contains length of bitfield
	 *   {hardwarespecific} contains width of RAMDAC
	 *   cmap[X] is programmed to (X << red.offset) | (X << green.offset) | (X << blue.offset)
	 *   RAMDAC[X] is programmed to (red, green, blue)
	 * 
	 * Pseudocolor:
	 *    uses offset = 0 && length = RAMDAC register width.
	 *    var->{color}.offset is 0
	 *    var->{color}.length contains widht of DAC
	 *    cmap is not used
	 *    RAMDAC[X] is programmed to (red, green, blue)
	 * Truecolor:
	 *    does not use DAC. Usually 3 are present.
	 *    var->{color}.offset contains start of bitfield
	 *    var->{color}.length contains length of bitfield
	 *    cmap is programmed to (red << red.offset) | (green << green.offset) |
	 *                      (blue << blue.offset) | (transp << transp.offset)
	 *    RAMDAC does not exist
	 */
#define CNVT_TOHW(val,width) ((((val)<<(width))+0x7FFF-(val))>>16)
	switch (info->fix.visual) {
	case FB_VISUAL_TRUECOLOR:
	case FB_VISUAL_PSEUDOCOLOR:
		red = CNVT_TOHW(red, info->var.red.length);
		green = CNVT_TOHW(green, info->var.green.length);
		blue = CNVT_TOHW(blue, info->var.blue.length);
		transp = CNVT_TOHW(transp, info->var.transp.length);
		break;
	case FB_VISUAL_DIRECTCOLOR:
		red = CNVT_TOHW(red, 8);	/* expect 8 bit DAC */
		green = CNVT_TOHW(green, 8);
		blue = CNVT_TOHW(blue, 8);
		/* hey, there is bug in transp handling... */
		transp = CNVT_TOHW(transp, 8);
		break;
	}
#undef CNVT_TOHW
	/* Truecolor has hardware independent palette */
	if (info->fix.visual == FB_VISUAL_TRUECOLOR) {
		u32 v;

		if (regno >= 16)
			return 1;

		v = (red << info->var.red.offset) |
		    (green << info->var.green.offset) |
		    (blue << info->var.blue.offset) |
		    (transp << info->var.transp.offset);
		switch (info->var.bits_per_pixel) {
		case 8:
			break;
		case 16:
			((u32 *) (info->pseudo_palette))[regno] = v;
			break;
		case 24:
		case 32:
			((u32 *) (info->pseudo_palette))[regno] = v;
			break;
		}
		return 0;
	}
	return 0;
}

    /*
     *  Pan or Wrap the Display
     *
     *  This call looks only at xoffset, yoffset and the FB_VMODE_YWRAP flag
     */

static int vfb_pan_display(struct fb_var_screeninfo *var,
			   struct fb_info *info)
{
	if (var->vmode & FB_VMODE_YWRAP) {
		if (var->yoffset < 0
		    || var->yoffset >= info->var.yres_virtual
		    || var->xoffset)
			return -EINVAL;
	} else {
		if (var->xoffset + var->xres > info->var.xres_virtual ||
		    var->yoffset + var->yres > info->var.yres_virtual)
			return -EINVAL;
	}
	info->var.xoffset = var->xoffset;
	info->var.yoffset = var->yoffset;
	if (var->vmode & FB_VMODE_YWRAP)
		info->var.vmode |= FB_VMODE_YWRAP;
	else
		info->var.vmode &= ~FB_VMODE_YWRAP;
	return 0;
}

    /*
     *  Most drivers don't need their own mmap function 
     */

static int vfb_mmap(struct fb_info *info, struct file *file,
		    struct vm_area_struct *vma)
{
	return -EINVAL;
}

#ifndef MODULE
static int __init vfb_setup(char *options)
{
	char *this_opt;

	vfb_enable = 1;

	if (!options || !*options)
		return 1;

	while ((this_opt = strsep(&options, ",")) != NULL) {
		if (!*this_opt)
			continue;
		if (!strncmp(this_opt, "disable", 7))
			vfb_enable = 0;
	}
	return 1;
}
#endif  /*  MODULE  */

    /*
     *  Initialisation
     */

static void vfb_platform_release(struct device *device)
{
	// This is called when the reference count goes to zero.
}

static int __init vfb_probe(struct platform_device *dev)
{
	struct fb_info *info;
	int retval = -ENOMEM;

	/*
	 * For real video cards we use ioremap.
	 */
	if (!(videomemory = vmalloc(videomemorysize)))
		return retval;

	/*
	 * VFB must clear memory to prevent kernel info
	 * leakage into userspace
	 * VGA-based drivers MUST NOT clear memory if
	 * they want to be able to take over vgacon
	 */
	memset(videomemory, 0, videomemorysize);

	info = framebuffer_alloc(sizeof(u32) * 256, &dev->dev);
	if (!info)
		goto err;

	info->screen_base = (char __iomem *)videomemory;
	info->fbops = &vfb_ops;

	retval = fb_find_mode(&info->var, info, NULL,
			      NULL, 0, NULL, 8);

	if (!retval || (retval == 4))
		info->var = vfb_default;
	info->fix = vfb_fix;
	info->pseudo_palette = info->par;
	info->par = NULL;
	info->flags = FBINFO_FLAG_DEFAULT;

	retval = fb_alloc_cmap(&info->cmap, 256, 0);
	if (retval < 0)
		goto err1;

	retval = register_framebuffer(info);
	if (retval < 0)
		goto err2;
	platform_set_drvdata(dev, info);

	printk(KERN_INFO
	       "fb%d: Virtual frame buffer device, using %ldK of video memory\n",
	       info->node, videomemorysize >> 10);
	return 0;
err2:
	fb_dealloc_cmap(&info->cmap);
err1:
	framebuffer_release(info);
err:
	vfree(videomemory);
	return retval;
}

static int vfb_remove(struct platform_device *dev)
{
	struct fb_info *info = platform_get_drvdata(dev);

	if (info) {
		unregister_framebuffer(info);
		vfree(videomemory);
		framebuffer_release(info);
	}
	return 0;
}

static struct platform_driver vfb_driver = {
	.probe	= vfb_probe,
	.remove = vfb_remove,
	.driver = {
		.name	= "vfb",
	},
};

static struct platform_device vfb_device = {
	.name	= "vfb",
	.id	= 0,
	.dev	= {
		.release = vfb_platform_release,
	}
};

static int __init vfb_init(void)
{
	int ret = 0;

#ifndef MODULE
	char *option = NULL;

	if (fb_get_options("vfb", &option))
		return -ENODEV;
	vfb_setup(option);
#endif

	if (!vfb_enable)
		return -ENXIO;

	ret = platform_driver_register(&vfb_driver);

	if (!ret) {
		ret = platform_device_register(&vfb_device);
		if (ret)
			platform_driver_unregister(&vfb_driver);
	}
	return ret;
}

module_init(vfb_init);

#ifdef MODULE
static void __exit vfb_exit(void)
{
	platform_device_unregister(&vfb_device);
	platform_driver_unregister(&vfb_driver);
}

module_exit(vfb_exit);

MODULE_LICENSE("GPL");
#endif				/* MODULE */
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/drivers/video/vfb.c -- Virtual frame buffer device
	3	*
	4	* Copyright (C) 2002 James Simmons
	5	*
	6	* Copyright (C) 1997 Geert Uytterhoeven
	7	*
	8	* This file is subject to the terms and conditions of the GNU General Public
	9	* License. See the file COPYING in the main directory of this archive for
	10	* more details.
	11	*/
	12
	13	#include <linux/module.h>
	14	#include <linux/kernel.h>
	15	#include <linux/errno.h>
	16	#include <linux/string.h>
	17	#include <linux/mm.h>
	18	#include <linux/tty.h>
	19	#include <linux/slab.h>
	20	#include <linux/vmalloc.h>
	21	#include <linux/delay.h>
	22	#include <linux/interrupt.h>
d052d1be RK	23	#include <linux/platform_device.h>
d052d1be RK	24
1da177e4 LT	25	#include <asm/uaccess.h>
	26	#include <linux/fb.h>
	27	#include <linux/init.h>
	28
	29	/*
	30	* RAM we reserve for the frame buffer. This defines the maximum screen
	31	* size
	32	*
	33	* The default can be overridden if the driver is compiled as a module
	34	*/
	35
	36	#define VIDEOMEMSIZE (110241024) /* 1 MB */
	37
	38	static void *videomemory;
	39	static u_long videomemorysize = VIDEOMEMSIZE;
	40	module_param(videomemorysize, ulong, 0);
	41
	42	static struct fb_var_screeninfo vfb_default __initdata = {
	43	.xres = 640,
	44	.yres = 480,
	45	.xres_virtual = 640,
	46	.yres_virtual = 480,
	47	.bits_per_pixel = 8,
	48	.red = { 0, 8, 0 },
	49	.green = { 0, 8, 0 },
	50	.blue = { 0, 8, 0 },
	51	.activate = FB_ACTIVATE_TEST,
	52	.height = -1,
	53	.width = -1,
	54	.pixclock = 20000,
	55	.left_margin = 64,
	56	.right_margin = 64,
	57	.upper_margin = 32,
	58	.lower_margin = 32,
	59	.hsync_len = 64,
	60	.vsync_len = 2,
	61	.vmode = FB_VMODE_NONINTERLACED,
	62	};
	63
	64	static struct fb_fix_screeninfo vfb_fix __initdata = {
	65	.id = "Virtual FB",
	66	.type = FB_TYPE_PACKED_PIXELS,
	67	.visual = FB_VISUAL_PSEUDOCOLOR,
	68	.xpanstep = 1,
	69	.ypanstep = 1,
	70	.ywrapstep = 1,
	71	.accel = FB_ACCEL_NONE,
	72	};
	73
	74	static int vfb_enable __initdata = 0; /* disabled by default */
	75	module_param(vfb_enable, bool, 0);
	76
	77	static int vfb_check_var(struct fb_var_screeninfo *var,
	78	struct fb_info *info);
	79	static int vfb_set_par(struct fb_info *info);
	80	static int vfb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
	81	u_int transp, struct fb_info *info);
	82	static int vfb_pan_display(struct fb_var_screeninfo *var,
	83	struct fb_info *info);
	84	static int vfb_mmap(struct fb_info info, struct file file,
	85	struct vm_area_struct *vma);
	86
	87	static struct fb_ops vfb_ops = {
	88	.fb_check_var = vfb_check_var,
89	.fb_set_par = vfb_set_par,
90	.fb_setcolreg = vfb_setcolreg,
91	.fb_pan_display = vfb_pan_display,
92	.fb_fillrect = cfb_fillrect,
93	.fb_copyarea = cfb_copyarea,
94	.fb_imageblit = cfb_imageblit,
1da177e4 LT	95	.fb_mmap = vfb_mmap,
	96	};
	97
	98	/*
	99	* Internal routines
	100	*/
	101
	102	static u_long get_line_length(int xres_virtual, int bpp)
	103	{
	104	u_long length;
	105
	106	length = xres_virtual * bpp;
	107	length = (length + 31) & ~31;
	108	length >>= 3;
	109	return (length);
	110	}
	111
	112	/*
	113	* Setting the video mode has been split into two parts.
	114	* First part, xxxfb_check_var, must not write anything
	115	* to hardware, it should only verify and adjust var.
	116	* This means it doesn't alter par but it does use hardware
	117	* data from it to check this var.
	118	*/
	119
	120	static int vfb_check_var(struct fb_var_screeninfo *var,
	121	struct fb_info *info)
	122	{
	123	u_long line_length;
	124
	125	/*
	126	* FB_VMODE_CONUPDATE and FB_VMODE_SMOOTH_XPAN are equal!
	127	* as FB_VMODE_SMOOTH_XPAN is only used internally
	128	*/
	129
	130	if (var->vmode & FB_VMODE_CONUPDATE) {
	131	var->vmode \|= FB_VMODE_YWRAP;
	132	var->xoffset = info->var.xoffset;
	133	var->yoffset = info->var.yoffset;
	134	}
	135
	136	/*
	137	* Some very basic checks
	138	*/
	139	if (!var->xres)
	140	var->xres = 1;
	141	if (!var->yres)
	142	var->yres = 1;
	143	if (var->xres > var->xres_virtual)
	144	var->xres_virtual = var->xres;
	145	if (var->yres > var->yres_virtual)
	146	var->yres_virtual = var->yres;
	147	if (var->bits_per_pixel <= 1)
	148	var->bits_per_pixel = 1;
	149	else if (var->bits_per_pixel <= 8)
	150	var->bits_per_pixel = 8;
	151	else if (var->bits_per_pixel <= 16)
	152	var->bits_per_pixel = 16;
	153	else if (var->bits_per_pixel <= 24)
	154	var->bits_per_pixel = 24;
	155	else if (var->bits_per_pixel <= 32)
	156	var->bits_per_pixel = 32;
	157	else
	158	return -EINVAL;
159
160	if (var->xres_virtual < var->xoffset + var->xres)
161	var->xres_virtual = var->xoffset + var->xres;
162	if (var->yres_virtual < var->yoffset + var->yres)
163	var->yres_virtual = var->yoffset + var->yres;
164
165	/*
166	* Memory limit
167	*/
168	line_length =
169	get_line_length(var->xres_virtual, var->bits_per_pixel);
170	if (line_length * var->yres_virtual > videomemorysize)
171	return -ENOMEM;
172
173	/*
174	* Now that we checked it we alter var. The reason being is that the video
175	* mode passed in might not work but slight changes to it might make it
176	* work. This way we let the user know what is acceptable.
177	*/
178	switch (var->bits_per_pixel) {
179	case 1:
180	case 8:
181	var->red.offset = 0;
182	var->red.length = 8;
183	var->green.offset = 0;
184	var->green.length = 8;
185	var->blue.offset = 0;
186	var->blue.length = 8;
187	var->transp.offset = 0;
188	var->transp.length = 0;
189	break;
190	case 16: /* RGBA 5551 */
191	if (var->transp.length) {
192	var->red.offset = 0;
193	var->red.length = 5;
194	var->green.offset = 5;
195	var->green.length = 5;
196	var->blue.offset = 10;
197	var->blue.length = 5;
198	var->transp.offset = 15;
199	var->transp.length = 1;
200	} else { /* RGB 565 */
201	var->red.offset = 0;
202	var->red.length = 5;
203	var->green.offset = 5;
204	var->green.length = 6;
205	var->blue.offset = 11;
206	var->blue.length = 5;
207	var->transp.offset = 0;
208	var->transp.length = 0;
209	}
210	break;
211	case 24: /* RGB 888 */
212	var->red.offset = 0;
213	var->red.length = 8;
214	var->green.offset = 8;
215	var->green.length = 8;
216	var->blue.offset = 16;
217	var->blue.length = 8;
218	var->transp.offset = 0;
219	var->transp.length = 0;
220	break;
221	case 32: /* RGBA 8888 */
222	var->red.offset = 0;
223	var->red.length = 8;
224	var->green.offset = 8;
225	var->green.length = 8;
226	var->blue.offset = 16;
227	var->blue.length = 8;
228	var->transp.offset = 24;
229	var->transp.length = 8;
230	break;
231	}
232	var->red.msb_right = 0;
233	var->green.msb_right = 0;
234	var->blue.msb_right = 0;
235	var->transp.msb_right = 0;
236
237	return 0;
238	}
239
240	/* This routine actually sets the video mode. It's in here where we
241	* the hardware state info->par and fix which can be affected by the
242	* change in par. For this driver it doesn't do much.
243	*/
244	static int vfb_set_par(struct fb_info *info)
245	{
246	info->fix.line_length = get_line_length(info->var.xres_virtual,
247	info->var.bits_per_pixel);
248	return 0;
249	}
250
251	/*
252	* Set a single color register. The values supplied are already
253	* rounded down to the hardware's capabilities (according to the
254	* entries in the var structure). Return != 0 for invalid regno.
255	*/
256
257	static int vfb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
258	u_int transp, struct fb_info *info)
259	{
260	if (regno >= 256) /* no. of hw registers */
261	return 1;
262	/*
263	* Program hardware... do anything you want with transp
264	*/
265
266	/* grayscale works only partially under directcolor */
267	if (info->var.grayscale) {
268	/* grayscale = 0.30R + 0.59G + 0.11B /
269	red = green = blue =
270	(red * 77 + green * 151 + blue * 28) >> 8;
271	}
272
273	/* Directcolor:
274	* var->{color}.offset contains start of bitfield
275	* var->{color}.length contains length of bitfield
276	* {hardwarespecific} contains width of RAMDAC
277	* cmap[X] is programmed to (X << red.offset) \| (X << green.offset) \| (X << blue.offset)
278	* RAMDAC[X] is programmed to (red, green, blue)
279	*
280	* Pseudocolor:
281	* uses offset = 0 && length = RAMDAC register width.
282	* var->{color}.offset is 0
283	* var->{color}.length contains widht of DAC
284	* cmap is not used
285	* RAMDAC[X] is programmed to (red, green, blue)
286	* Truecolor:
287	* does not use DAC. Usually 3 are present.
288	* var->{color}.offset contains start of bitfield
289	* var->{color}.length contains length of bitfield
290	* cmap is programmed to (red << red.offset) \| (green << green.offset) \|
291	* (blue << blue.offset) \| (transp << transp.offset)
292	* RAMDAC does not exist
293	*/
294	#define CNVT_TOHW(val,width) ((((val)<<(width))+0x7FFF-(val))>>16)
295	switch (info->fix.visual) {
296	case FB_VISUAL_TRUECOLOR:
297	case FB_VISUAL_PSEUDOCOLOR:
298	red = CNVT_TOHW(red, info->var.red.length);
299	green = CNVT_TOHW(green, info->var.green.length);
300	blue = CNVT_TOHW(blue, info->var.blue.length);
301	transp = CNVT_TOHW(transp, info->var.transp.length);
302	break;
303	case FB_VISUAL_DIRECTCOLOR:
304	red = CNVT_TOHW(red, 8); /* expect 8 bit DAC */
305	green = CNVT_TOHW(green, 8);
306	blue = CNVT_TOHW(blue, 8);
307	/* hey, there is bug in transp handling... */
308	transp = CNVT_TOHW(transp, 8);
309	break;
310	}
311	#undef CNVT_TOHW
312	/* Truecolor has hardware independent palette */
313	if (info->fix.visual == FB_VISUAL_TRUECOLOR) {
314	u32 v;
315
316	if (regno >= 16)
317	return 1;
318
319	v = (red << info->var.red.offset) \|
320	(green << info->var.green.offset) \|
321	(blue << info->var.blue.offset) \|
322	(transp << info->var.transp.offset);
323	switch (info->var.bits_per_pixel) {
324	case 8:
325	break;
326	case 16:
327	((u32 *) (info->pseudo_palette))[regno] = v;
328	break;
329	case 24:
330	case 32:
331	((u32 *) (info->pseudo_palette))[regno] = v;
332	break;
333	}
334	return 0;
335	}
336	return 0;
337	}
338
339	/*
340	* Pan or Wrap the Display
341	*
342	* This call looks only at xoffset, yoffset and the FB_VMODE_YWRAP flag
343	*/
344
345	static int vfb_pan_display(struct fb_var_screeninfo *var,
346	struct fb_info *info)
347	{
348	if (var->vmode & FB_VMODE_YWRAP) {
349	if (var->yoffset < 0
350	\|\| var->yoffset >= info->var.yres_virtual
351	\|\| var->xoffset)
352	return -EINVAL;
353	} else {
354	if (var->xoffset + var->xres > info->var.xres_virtual \|\|
355	var->yoffset + var->yres > info->var.yres_virtual)
356	return -EINVAL;
357	}
358	info->var.xoffset = var->xoffset;
359	info->var.yoffset = var->yoffset;
360	if (var->vmode & FB_VMODE_YWRAP)
361	info->var.vmode \|= FB_VMODE_YWRAP;
362	else
363	info->var.vmode &= ~FB_VMODE_YWRAP;
364	return 0;
365	}
366
367	/*
368	* Most drivers don't need their own mmap function
369	*/
370
371	static int vfb_mmap(struct fb_info info, struct file file,
372	struct vm_area_struct *vma)
373	{
374	return -EINVAL;
375	}
376
377	#ifndef MODULE
378	static int __init vfb_setup(char *options)
379	{
380	char *this_opt;
381
382	vfb_enable = 1;
383
384	if (!options \|\| !*options)
385	return 1;
386
387	while ((this_opt = strsep(&options, ",")) != NULL) {
388	if (!*this_opt)
389	continue;
390	if (!strncmp(this_opt, "disable", 7))
391	vfb_enable = 0;
392	}
393	return 1;
394	}
395	#endif /* MODULE */
396
397	/*
398	* Initialisation
399	*/
400
401	static void vfb_platform_release(struct device *device)
402	{
403	// This is called when the reference count goes to zero.
404	}
405
3ae5eaec	406	static int __init vfb_probe(struct platform_device *dev)
1da177e4	407	{
1da177e4 LT	408	struct fb_info *info;
	409	int retval = -ENOMEM;
	410
	411	/*
	412	* For real video cards we use ioremap.
	413	*/
	414	if (!(videomemory = vmalloc(videomemorysize)))
	415	return retval;
	416
	417	/*
	418	* VFB must clear memory to prevent kernel info
	419	* leakage into userspace
	420	* VGA-based drivers MUST NOT clear memory if
	421	* they want to be able to take over vgacon
	422	*/
	423	memset(videomemory, 0, videomemorysize);
	424
	425	info = framebuffer_alloc(sizeof(u32) * 256, &dev->dev);
	426	if (!info)
	427	goto err;
	428
	429	info->screen_base = (char __iomem *)videomemory;
	430	info->fbops = &vfb_ops;
	431
	432	retval = fb_find_mode(&info->var, info, NULL,
	433	NULL, 0, NULL, 8);
	434
	435	if (!retval \|\| (retval == 4))
	436	info->var = vfb_default;
	437	info->fix = vfb_fix;
	438	info->pseudo_palette = info->par;
	439	info->par = NULL;
	440	info->flags = FBINFO_FLAG_DEFAULT;
	441
	442	retval = fb_alloc_cmap(&info->cmap, 256, 0);
	443	if (retval < 0)
	444	goto err1;
	445
	446	retval = register_framebuffer(info);
	447	if (retval < 0)
	448	goto err2;
3ae5eaec	449	platform_set_drvdata(dev, info);
1da177e4 LT	450
	451	printk(KERN_INFO
	452	"fb%d: Virtual frame buffer device, using %ldK of video memory\n",
	453	info->node, videomemorysize >> 10);
	454	return 0;
	455	err2:
	456	fb_dealloc_cmap(&info->cmap);
	457	err1:
	458	framebuffer_release(info);
	459	err:
	460	vfree(videomemory);
	461	return retval;
	462	}
	463
3ae5eaec	464	static int vfb_remove(struct platform_device *dev)
1da177e4	465	{
3ae5eaec	466	struct fb_info *info = platform_get_drvdata(dev);
1da177e4 LT	467
	468	if (info) {
	469	unregister_framebuffer(info);
	470	vfree(videomemory);
	471	framebuffer_release(info);
	472	}
	473	return 0;
	474	}
	475
3ae5eaec	476	static struct platform_driver vfb_driver = {
1da177e4 LT	477	.probe = vfb_probe,
1da177e4 LT	478	.remove = vfb_remove,
3ae5eaec RK	479	.driver = {
	480	.name = "vfb",
	481	},
1da177e4 LT	482	};
	483
	484	static struct platform_device vfb_device = {
	485	.name = "vfb",
	486	.id = 0,
	487	.dev = {
	488	.release = vfb_platform_release,
	489	}
	490	};
	491
	492	static int __init vfb_init(void)
	493	{
	494	int ret = 0;
	495
	496	#ifndef MODULE
	497	char *option = NULL;
	498
	499	if (fb_get_options("vfb", &option))
	500	return -ENODEV;
	501	vfb_setup(option);
	502	#endif
	503
	504	if (!vfb_enable)
	505	return -ENXIO;
	506
3ae5eaec	507	ret = platform_driver_register(&vfb_driver);
1da177e4 LT	508
	509	if (!ret) {
	510	ret = platform_device_register(&vfb_device);
	511	if (ret)
3ae5eaec	512	platform_driver_unregister(&vfb_driver);
1da177e4 LT	513	}
	514	return ret;
	515	}
	516
	517	module_init(vfb_init);
	518
	519	#ifdef MODULE
	520	static void __exit vfb_exit(void)
	521	{
	522	platform_device_unregister(&vfb_device);
3ae5eaec	523	platform_driver_unregister(&vfb_driver);
1da177e4 LT	524	}
	525
	526	module_exit(vfb_exit);
	527
	528	MODULE_LICENSE("GPL");
	529	#endif /* MODULE */