| /* |
| * 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); |
| static char *mode_option __devinitdata; |
| static int bpp __devinitdata = 8; |
| |
| module_param(mode_option, charp, 0); |
| MODULE_PARM_DESC(mode_option, "Initial video mode e.g. '648x480-8@60'"); |
| module_param(bpp, int, 0); |
| |
| |
| /********************************************************************** |
| * |
| * Memory management |
| * |
| **********************************************************************/ |
| static void *rvmalloc(unsigned long size) |
| { |
| void *mem; |
| unsigned long adr; |
| |
| size = PAGE_ALIGN(size); |
| mem = vmalloc_32(size); |
| if (!mem) |
| return NULL; |
| |
| memset(mem, 0, size); /* Clear the ram out, no junk to the user */ |
| adr = (unsigned long) mem; |
| while (size > 0) { |
| SetPageReserved(vmalloc_to_page((void *)adr)); |
| adr += PAGE_SIZE; |
| size -= PAGE_SIZE; |
| } |
| |
| return mem; |
| } |
| |
| static void rvfree(void *mem, unsigned long size) |
| { |
| unsigned long adr; |
| |
| if (!mem) |
| return; |
| |
| adr = (unsigned long) mem; |
| while ((long) size > 0) { |
| ClearPageReserved(vmalloc_to_page((void *)adr)); |
| adr += PAGE_SIZE; |
| size -= PAGE_SIZE; |
| } |
| vfree(mem); |
| } |
| |
| static struct fb_var_screeninfo vfb_default __devinitdata = { |
| .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 __devinitdata = { |
| .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 vm_area_struct *vma); |
| |
| static struct fb_ops vfb_ops = { |
| .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) |
| { |
| 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 < 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 vm_area_struct *vma) |
| { |
| unsigned long start = vma->vm_start; |
| unsigned long size = vma->vm_end - vma->vm_start; |
| unsigned long offset = vma->vm_pgoff << PAGE_SHIFT; |
| unsigned long page, pos; |
| |
| if (offset + size > info->fix.smem_len) { |
| return -EINVAL; |
| } |
| |
| pos = (unsigned long)info->fix.smem_start + offset; |
| |
| while (size > 0) { |
| page = vmalloc_to_pfn((void *)pos); |
| if (remap_pfn_range(vma, start, page, PAGE_SIZE, PAGE_SHARED)) { |
| return -EAGAIN; |
| } |
| start += PAGE_SIZE; |
| pos += PAGE_SIZE; |
| if (size > PAGE_SIZE) |
| size -= PAGE_SIZE; |
| else |
| size = 0; |
| } |
| |
| vma->vm_flags |= VM_RESERVED; /* avoid to swap out this VMA */ |
| return 0; |
| |
| } |
| |
| #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 if (!strncmp(this_opt, "bpp=", 4)) { |
| if (kstrtoint(this_opt + 4, 0, &bpp) < 0) |
| bpp = 8; |
| } else if (!strncmp(this_opt, "memsize=", 8)) { |
| if (kstrtoul(this_opt + 8, 0, &videomemorysize) < 0) |
| videomemorysize = VIDEOMEMSIZE; |
| } else |
| mode_option = this_opt; |
| } |
| return 1; |
| } |
| #endif /* MODULE */ |
| |
| /* |
| * Initialisation |
| */ |
| |
| static int __devinit vfb_probe(struct platform_device *dev) |
| { |
| struct fb_info *info; |
| int retval = -ENOMEM; |
| |
| /* |
| * For real video cards we use ioremap. |
| */ |
| if (!(videomemory = rvmalloc(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, mode_option, |
| NULL, 0, NULL, bpp); |
| |
| if (!retval || (retval == 4)) |
| info->var = vfb_default; |
| vfb_fix.smem_start = (unsigned long) videomemory; |
| vfb_fix.smem_len = videomemorysize; |
| 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: |
| rvfree(videomemory, videomemorysize); |
| return retval; |
| } |
| |
| static int vfb_remove(struct platform_device *dev) |
| { |
| struct fb_info *info = platform_get_drvdata(dev); |
| |
| if (info) { |
| unregister_framebuffer(info); |
| rvfree(videomemory, videomemorysize); |
| fb_dealloc_cmap(&info->cmap); |
| 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; |
| |
| 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 */ |