1 files changed, 550 insertions, 0 deletions

diff --git a/drivers/video/fbdev/vfb.c b/drivers/video/fbdev/vfb.c
new file mode 100644
index 0000000000..1b7c338f99
--- /dev/null
+++ b/drivers/video/fbdev/vfb.c
@@ -0,0 +1,550 @@
+/*
+ *  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/vmalloc.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.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);
+MODULE_PARM_DESC(videomemorysize, "RAM available to frame buffer (in bytes)");
+
+static char *mode_option = NULL;
+module_param(mode_option, charp, 0);
+MODULE_PARM_DESC(mode_option, "Preferred video mode (e.g. 640x480-8@60)");
+
+static const struct fb_videomode vfb_default = {
+	.xres =		640,
+	.yres =		480,
+	.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 = {
+	.id =		"Virtual FB",
+	.type =		FB_TYPE_PACKED_PIXELS,
+	.visual =	FB_VISUAL_PSEUDOCOLOR,
+	.xpanstep =	1,
+	.ypanstep =	1,
+	.ywrapstep =	1,
+	.accel =	FB_ACCEL_NONE,
+};
+
+static bool vfb_enable __initdata = 0;	/* disabled by default */
+module_param(vfb_enable, bool, 0);
+MODULE_PARM_DESC(vfb_enable, "Enable Virtual FB driver");
+
+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 vm_area_struct *vma);
+
+static const struct fb_ops vfb_ops = {
+	.owner		= THIS_MODULE,
+	.fb_read        = fb_sys_read,
+	.fb_write       = fb_sys_write,
+	.fb_check_var	= vfb_check_var,
+	.fb_set_par	= vfb_set_par,
+	.fb_setcolreg	= vfb_setcolreg,
+	.fb_pan_display	= vfb_pan_display,
+	.fb_fillrect	= sys_fillrect,
+	.fb_copyarea	= sys_copyarea,
+	.fb_imageblit	= sys_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)
+{
+	switch (info->var.bits_per_pixel) {
+	case 1:
+		info->fix.visual = FB_VISUAL_MONO01;
+		break;
+	case 8:
+		info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
+		break;
+	case 16:
+	case 24:
+	case 32:
+		info->fix.visual = FB_VISUAL_TRUECOLOR;
+		break;
+	}
+
+	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:
+	 *    var->{color}.offset is 0 unless the palette index takes less than
+	 *                        bits_per_pixel bits and is stored in the upper
+	 *                        bits of the pixel value
+	 *    var->{color}.length is set so that 1 << length is the number of available
+	 *                        palette entries
+	 *    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 >= info->var.yres_virtual ||
+		    var->xoffset)
+			return -EINVAL;
+	} else {
+		if (var->xoffset + info->var.xres > info->var.xres_virtual ||
+		    var->yoffset + info->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 vm_area_struct *vma)
+{
+	return remap_vmalloc_range(vma, (void *)info->fix.smem_start, vma->vm_pgoff);
+}
+
+#ifndef MODULE
+/*
+ * The virtual framebuffer driver is only enabled if explicitly
+ * requested by passing 'video=vfb:' (or any actual options).
+ */
+static int __init vfb_setup(char *options)
+{
+	char *this_opt;
+
+	vfb_enable = 0;
+
+	if (!options)
+		return 1;
+
+	vfb_enable = 1;
+
+	if (!*options)
+		return 1;
+
+	while ((this_opt = strsep(&options, ",")) != NULL) {
+		if (!*this_opt)
+			continue;
+		/* Test disable for backwards compatibility */
+		if (!strcmp(this_opt, "disable"))
+			vfb_enable = 0;
+		else
+			mode_option = this_opt;
+	}
+	return 1;
+}
+#endif  /*  MODULE  */
+
+    /*
+     *  Initialisation
+     */
+
+static int vfb_probe(struct platform_device *dev)
+{
+	struct fb_info *info;
+	unsigned int size = PAGE_ALIGN(videomemorysize);
+	int retval = -ENOMEM;
+
+	/*
+	 * For real video cards we use ioremap.
+	 */
+	if (!(videomemory = vmalloc_32_user(size)))
+		return retval;
+
+	info = framebuffer_alloc(sizeof(u32) * 256, &dev->dev);
+	if (!info)
+		goto err;
+
+	info->screen_buffer = videomemory;
+	info->fbops = &vfb_ops;
+
+	if (!fb_find_mode(&info->var, info, mode_option,
+			  NULL, 0, &vfb_default, 8)){
+		fb_err(info, "Unable to find usable video mode.\n");
+		retval = -EINVAL;
+		goto err1;
+	}
+
+	vfb_fix.smem_start = (unsigned long) videomemory;
+	vfb_fix.smem_len = videomemorysize;
+	info->fix = vfb_fix;
+	info->pseudo_palette = info->par;
+	info->par = NULL;
+
+	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);
+
+	vfb_set_par(info);
+
+	fb_info(info, "Virtual frame buffer device, using %ldK of video memory\n",
+		videomemorysize >> 10);
+	return 0;
+err2:
+	fb_dealloc_cmap(&info->cmap);
+err1:
+	framebuffer_release(info);
+err:
+	vfree(videomemory);
+	return retval;
+}
+
+static void vfb_remove(struct platform_device *dev)
+{
+	struct fb_info *info = platform_get_drvdata(dev);
+
+	if (info) {
+		unregister_framebuffer(info);
+		vfree(videomemory);
+		fb_dealloc_cmap(&info->cmap);
+		framebuffer_release(info);
+	}
+}
+
+static struct platform_driver vfb_driver = {
+	.probe	= vfb_probe,
+	.remove_new = vfb_remove,
+	.driver = {
+		.name	= "vfb",
+	},
+};
+
+static struct platform_device *vfb_device;
+
+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) {
+		vfb_device = platform_device_alloc("vfb", 0);
+
+		if (vfb_device)
+			ret = platform_device_add(vfb_device);
+		else
+			ret = -ENOMEM;
+
+		if (ret) {
+			platform_device_put(vfb_device);
+			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 */