fbmem.c

《linux驱动程序设计从入门到精通》一书中所有的程序代码含驱动和相应的应用程序

			fb_pan_display(info, &info->var);

			fb_set_cmap(&info->cmap, info);

			if (info->flags & FBINFO_MISC_MODECHANGEUSER) {
				info->flags &= ~FBINFO_MISC_MODECHANGEUSER;
				notifier_call_chain(&fb_notifier_list,
						    FB_EVENT_MODE_CHANGE, info);
			}
		}
	}
	return 0;
}

int
fb_blank(struct fb_info *info, int blank)
{	
	/* ??? Variable sized stack allocation.  */
	u16 black[info->cmap.len];
	struct fb_cmap cmap;
	
	if (info->fbops->fb_blank && !info->fbops->fb_blank(blank, info))
		return 0;
	if (blank) { 
		memset(black, 0, info->cmap.len * sizeof(u16));
		cmap.red = cmap.green = cmap.blue = black;
		cmap.transp = info->cmap.transp ? black : NULL;
		cmap.start = info->cmap.start;
		cmap.len = info->cmap.len;
	} else
		cmap = info->cmap;
	return fb_set_cmap(&cmap, info);
}

static int 
fb_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
	 unsigned long arg)
{
	int fbidx = iminor(inode);
	struct fb_info *info = registered_fb[fbidx];
	struct fb_ops *fb = info->fbops;
	struct fb_var_screeninfo var;
	struct fb_fix_screeninfo fix;
#ifdef CONFIG_FRAMEBUFFER_CONSOLE
	struct fb_con2fbmap con2fb;
#endif
	struct fb_cmap_user cmap;
	void __user *argp = (void __user *)arg;
	int i;
	
	if (!fb)
		return -ENODEV;
	switch (cmd) {
	case FBIOGET_VSCREENINFO:
		return copy_to_user(argp, &info->var,
				    sizeof(var)) ? -EFAULT : 0;
	case FBIOPUT_VSCREENINFO:
		if (copy_from_user(&var, argp, sizeof(var)))
			return -EFAULT;
		acquire_console_sem();
		info->flags |= FBINFO_MISC_MODECHANGEUSER;
		i = fb_set_var(info, &var);
		info->flags &= ~FBINFO_MISC_MODECHANGEUSER;
		release_console_sem();
		if (i) return i;
		if (copy_to_user(argp, &var, sizeof(var)))
			return -EFAULT;
		return 0;
	case FBIOGET_FSCREENINFO:
		return copy_to_user(argp, &info->fix,
				    sizeof(fix)) ? -EFAULT : 0;
	case FBIOPUTCMAP:
		if (copy_from_user(&cmap, argp, sizeof(cmap)))
			return -EFAULT;
		return (fb_set_user_cmap(&cmap, info));
	case FBIOGETCMAP:
		if (copy_from_user(&cmap, argp, sizeof(cmap)))
			return -EFAULT;
		return fb_cmap_to_user(&info->cmap, &cmap);
	case FBIOPAN_DISPLAY:
		if (copy_from_user(&var, argp, sizeof(var)))
			return -EFAULT;
		acquire_console_sem();
		i = fb_pan_display(info, &var);
		release_console_sem();
		if (i)
			return i;
		if (copy_to_user(argp, &var, sizeof(var)))
			return -EFAULT;
		return 0;
	case FBIO_CURSOR:
		acquire_console_sem();
		i = fb_cursor(info, argp);
		release_console_sem();
		return i;
#ifdef CONFIG_FRAMEBUFFER_CONSOLE
	case FBIOGET_CON2FBMAP:
		if (copy_from_user(&con2fb, argp, sizeof(con2fb)))
			return -EFAULT;
		if (con2fb.console < 1 || con2fb.console > MAX_NR_CONSOLES)
		    return -EINVAL;
		con2fb.framebuffer = con2fb_map[con2fb.console-1];
		return copy_to_user(argp, &con2fb,
				    sizeof(con2fb)) ? -EFAULT : 0;
	case FBIOPUT_CON2FBMAP:
		if (copy_from_user(&con2fb, argp, sizeof(con2fb)))
			return - EFAULT;
		if (con2fb.console < 0 || con2fb.console > MAX_NR_CONSOLES)
		    return -EINVAL;
		if (con2fb.framebuffer < 0 || con2fb.framebuffer >= FB_MAX)
		    return -EINVAL;
#ifdef CONFIG_KMOD
		if (!registered_fb[con2fb.framebuffer])
		    try_to_load(con2fb.framebuffer);
#endif /* CONFIG_KMOD */
		if (!registered_fb[con2fb.framebuffer])
		    return -EINVAL;
		if (con2fb.console > 0 && con2fb.console < MAX_NR_CONSOLES)
			return set_con2fb_map(con2fb.console-1,
					      con2fb.framebuffer);
		return -EINVAL;
#endif	/* CONFIG_FRAMEBUFFER_CONSOLE */
	case FBIOBLANK:
		acquire_console_sem();
		i = fb_blank(info, arg);
		release_console_sem();
		return i;
	default:
		if (fb->fb_ioctl == NULL)
			return -EINVAL;
		return fb->fb_ioctl(inode, file, cmd, arg, info);
	}
}

static int 
fb_mmap(struct file *file, struct vm_area_struct * vma)
{
	int fbidx = iminor(file->f_dentry->d_inode);
	struct fb_info *info = registered_fb[fbidx];
	struct fb_ops *fb = info->fbops;
	unsigned long off;
#if !defined(__sparc__) || defined(__sparc_v9__)
	unsigned long start;
	u32 len;
#endif

	if (vma->vm_pgoff > (~0UL >> PAGE_SHIFT))
		return -EINVAL;
	off = vma->vm_pgoff << PAGE_SHIFT;
	if (!fb)
		return -ENODEV;
	if (fb->fb_mmap) {
		int res;
		lock_kernel();
		res = fb->fb_mmap(info, file, vma);
		unlock_kernel();
		return res;
	}

#if defined(__sparc__) && !defined(__sparc_v9__)
	/* Should never get here, all fb drivers should have their own
	   mmap routines */
	return -EINVAL;
#else
	/* !sparc32... */
	lock_kernel();

	/* frame buffer memory */
	start = info->fix.smem_start;
	len = PAGE_ALIGN((start & ~PAGE_MASK) + info->fix.smem_len);
	if (off >= len) {
		/* memory mapped io */
		off -= len;
		if (info->var.accel_flags) {
			unlock_kernel();
			return -EINVAL;
		}
		start = info->fix.mmio_start;
		len = PAGE_ALIGN((start & ~PAGE_MASK) + info->fix.mmio_len);
	}
	unlock_kernel();
	start &= PAGE_MASK;
	if ((vma->vm_end - vma->vm_start + off) > len)
		return -EINVAL;
	off += start;
	vma->vm_pgoff = off >> PAGE_SHIFT;
	/* This is an IO map - tell maydump to skip this VMA */
	vma->vm_flags |= VM_IO;
#if defined(__sparc_v9__)
	vma->vm_flags |= (VM_SHM | VM_LOCKED);
	if (io_remap_page_range(vma, vma->vm_start, off,
				vma->vm_end - vma->vm_start, vma->vm_page_prot, 0))
		return -EAGAIN;
#else
#if defined(__mc68000__)
#if defined(CONFIG_SUN3)
	pgprot_val(vma->vm_page_prot) |= SUN3_PAGE_NOCACHE;
#elif defined(CONFIG_MMU)
	if (CPU_IS_020_OR_030)
		pgprot_val(vma->vm_page_prot) |= _PAGE_NOCACHE030;
	if (CPU_IS_040_OR_060) {
		pgprot_val(vma->vm_page_prot) &= _CACHEMASK040;
		/* Use no-cache mode, serialized */
		pgprot_val(vma->vm_page_prot) |= _PAGE_NOCACHE_S;
	}
#endif
#elif defined(__powerpc__)
	pgprot_val(vma->vm_page_prot) |= _PAGE_NO_CACHE|_PAGE_GUARDED;
#elif defined(__alpha__)
	/* Caching is off in the I/O space quadrant by design.  */
#elif defined(__i386__) || defined(__x86_64__)
	if (boot_cpu_data.x86 > 3)
		pgprot_val(vma->vm_page_prot) |= _PAGE_PCD;
#elif defined(__mips__)
	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
#elif defined(__hppa__)
	pgprot_val(vma->vm_page_prot) |= _PAGE_NO_CACHE;
#elif defined(__ia64__) || defined(__arm__) || defined(__sh__)
	vma->vm_page_prot = pgprot_writecombine(vma->vm_page_prot);
#else
#warning What do we have to do here??
#endif
	if (io_remap_page_range(vma, vma->vm_start, off,
			     vma->vm_end - vma->vm_start, vma->vm_page_prot))
		return -EAGAIN;
#endif /* !__sparc_v9__ */
	return 0;
#endif /* !sparc32 */
}

static int
fb_open(struct inode *inode, struct file *file)
{
	int fbidx = iminor(inode);
	struct fb_info *info;
	int res = 0;

	if (fbidx >= FB_MAX)
		return -ENODEV;
#ifdef CONFIG_KMOD
	if (!(info = registered_fb[fbidx]))
		try_to_load(fbidx);
#endif /* CONFIG_KMOD */
	if (!(info = registered_fb[fbidx]))
		return -ENODEV;
	if (!try_module_get(info->fbops->owner))
		return -ENODEV;
	if (info->fbops->fb_open) {
		res = info->fbops->fb_open(info,1);
		if (res)
			module_put(info->fbops->owner);
	}
	return res;
}

static int 
fb_release(struct inode *inode, struct file *file)
{
	int fbidx = iminor(inode);
	struct fb_info *info;

	lock_kernel();
	info = registered_fb[fbidx];
	if (info->fbops->fb_release)
		info->fbops->fb_release(info,1);
	module_put(info->fbops->owner);
	unlock_kernel();
	return 0;
}

static struct file_operations fb_fops = {
	.owner =	THIS_MODULE,
	.read =		fb_read,
	.write =	fb_write,
	.ioctl =	fb_ioctl,
	.mmap =		fb_mmap,
	.open =		fb_open,
	.release =	fb_release,
#ifdef HAVE_ARCH_FB_UNMAPPED_AREA
	.get_unmapped_area = get_fb_unmapped_area,
#endif
};

static struct class_simple *fb_class;

/**
 *	register_framebuffer - registers a frame buffer device
 *	@fb_info: frame buffer info structure
 *
 *	Registers a frame buffer device @fb_info.
 *
 *	Returns negative errno on error, or zero for success.
 *
 */

int
register_framebuffer(struct fb_info *fb_info)
{
	int i;
	struct class_device *c;

	if (num_registered_fb == FB_MAX)
		return -ENXIO;
	num_registered_fb++;
	for (i = 0 ; i < FB_MAX; i++)
		if (!registered_fb[i])
			break;
	fb_info->node = i;

	c = class_simple_device_add(fb_class, MKDEV(FB_MAJOR, i), NULL, "fb%d", i);
	if (IS_ERR(c)) {
		/* Not fatal */
		printk(KERN_WARNING "Unable to create class_device for framebuffer %d; errno = %ld\n", i, PTR_ERR(c));
	}
	
	if (fb_info->pixmap.addr == NULL) {
		fb_info->pixmap.addr = kmalloc(FBPIXMAPSIZE, GFP_KERNEL);
		if (fb_info->pixmap.addr) {
			fb_info->pixmap.size = FBPIXMAPSIZE;
			fb_info->pixmap.buf_align = 1;
			fb_info->pixmap.scan_align = 1;
			fb_info->pixmap.access_align = 4;
			fb_info->pixmap.flags = FB_PIXMAP_DEFAULT;
		}
	}	
	fb_info->pixmap.offset = 0;

	if (fb_info->sprite.addr == NULL) {
		fb_info->sprite.addr = kmalloc(FBPIXMAPSIZE, GFP_KERNEL);
		if (fb_info->sprite.addr) {
			fb_info->sprite.size = FBPIXMAPSIZE;
			fb_info->sprite.buf_align = 1;
			fb_info->sprite.scan_align = 1;
			fb_info->sprite.access_align = 4;
			fb_info->sprite.flags = FB_PIXMAP_DEFAULT;
		}
	}
	fb_info->sprite.offset = 0;

	registered_fb[i] = fb_info;

	devfs_mk_cdev(MKDEV(FB_MAJOR, i),
			S_IFCHR | S_IRUGO | S_IWUGO, "fb/%d", i);
	return 0;
}


/**
 *	unregister_framebuffer - releases a frame buffer device
 *	@fb_info: frame buffer info structure
 *
 *	Unregisters a frame buffer device @fb_info.
 *
 *	Returns negative errno on error, or zero for success.
 *
 */

int
unregister_framebuffer(struct fb_info *fb_info)
{
	int i;

	i = fb_info->node;
	if (!registered_fb[i])
		return -EINVAL;
	devfs_remove("fb/%d", i);

	if (fb_info->pixmap.addr && (fb_info->pixmap.flags & FB_PIXMAP_DEFAULT))
		kfree(fb_info->pixmap.addr);
	if (fb_info->sprite.addr && (fb_info->sprite.flags & FB_PIXMAP_DEFAULT))
		kfree(fb_info->sprite.addr);
	registered_fb[i]=NULL;
	num_registered_fb--;
	class_simple_device_remove(MKDEV(FB_MAJOR, i));
	return 0;
}

/**
 *	fb_register_client - register a client notifier
 *	@nb: notifier block to callback on events
 */
int fb_register_client(struct notifier_block *nb)
{
	return notifier_chain_register(&fb_notifier_list, nb);
}

/**
 *	fb_unregister_client - unregister a client notifier
 *	@nb: notifier block to callback on events
 */
int fb_unregister_client(struct notifier_block *nb)
{
	return notifier_chain_unregister(&fb_notifier_list, nb);
}

/**
 *	fb_set_suspend - low level driver signals suspend
 *	@info: framebuffer affected
 *	@state: 0 = resuming, !=0 = suspending
 *
 *	This is meant to be used by low level drivers to
 * 	signal suspend/resume to the core & clients.
 *	It must be called with the console semaphore held
 */
void fb_set_suspend(struct fb_info *info, int state)
{
	if (state) {
		notifier_call_chain(&fb_notifier_list, FB_EVENT_SUSPEND, info);
		info->state = FBINFO_STATE_SUSPENDED;
	} else {
		info->state = FBINFO_STATE_RUNNING;
		notifier_call_chain(&fb_notifier_list, FB_EVENT_RESUME, info);
	}
}

/**
 *	fbmem_init - init frame buffer subsystem
 *
 *	Initialize the frame buffer subsystem.
 *
 *	NOTE: This function is _only_ to be called by drivers/char/mem.c.
 *
 */

void __init 
fbmem_init(void)
{
	int i;

	create_proc_read_entry("fb", 0, NULL, fbmem_read_proc, NULL);

	devfs_mk_dir("fb");
	if (register_chrdev(FB_MAJOR,"fb",&fb_fops))
		printk("unable to get major %d for fb devs\n", FB_MAJOR);

	fb_class = class_simple_create(THIS_MODULE, "graphics");
	if (IS_ERR(fb_class)) {
		printk(KERN_WARNING "Unable to create fb class; errno = %ld\n", PTR_ERR(fb_class));
		fb_class = NULL;
	}

#ifdef CONFIG_FB_OF
	if (ofonly) {
		offb_init();
		return;
	}
#endif

	/*
	 *  Probe for all builtin frame buffer devices
	 */
	for (i = 0; i < num_pref_init_funcs; i++)
		pref_init_funcs[i]();

	for (i = 0; i < NUM_FB_DRIVERS; i++)
		if (fb_drivers[i].init)
			fb_drivers[i].init();
}


/**
 *	video_setup - process command line options
 *	@options: string of options
 *
 *	Process command line options for frame buffer subsystem.
 *
 *	NOTE: This function is a __setup and __init function.
 *
 *	Returns zero.
 *
 */

int __init video_setup(char *options)
{
	int i, j;

	if (!options || !*options)
		return 0;
	   
#ifdef CONFIG_FB_OF
	if (!strcmp(options, "ofonly")) {
		ofonly = 1;
		return 0;
	}
#endif

	if (num_pref_init_funcs == FB_MAX)
		return 0;

	for (i = 0; i < NUM_FB_DRIVERS; i++) {
		j = strlen(fb_drivers[i].name);
		if (!strncmp(options, fb_drivers[i].name, j) &&
			options[j] == ':') {
			if (!strcmp(options+j+1, "off"))
				fb_drivers[i].init = NULL;
			else {
				if (fb_drivers[i].init) {
					pref_init_funcs[num_pref_init_funcs++] =
						fb_drivers[i].init;
					fb_drivers[i].init = NULL;
				}
				if (fb_drivers[i].setup)
					fb_drivers[i].setup(options+j+1);
			}
			return 0;
		}
	}

	/*
	 * If we get here no fb was specified.
	 * We consider the argument to be a global video mode option.
	 */
	global_mode_option = options;
	return 0;
}

__setup("video=", video_setup);

    /*
     *  Visible symbols for modules
     */

EXPORT_SYMBOL(register_framebuffer);
EXPORT_SYMBOL(unregister_framebuffer);
EXPORT_SYMBOL(num_registered_fb);
EXPORT_SYMBOL(registered_fb);
EXPORT_SYMBOL(fb_prepare_logo);
EXPORT_SYMBOL(fb_show_logo);
EXPORT_SYMBOL(fb_set_var);
EXPORT_SYMBOL(fb_blank);
EXPORT_SYMBOL(fb_pan_display);
EXPORT_SYMBOL(fb_get_buffer_offset);
EXPORT_SYMBOL(fb_iomove_buf_unaligned);
EXPORT_SYMBOL(fb_iomove_buf_aligned);
EXPORT_SYMBOL(fb_sysmove_buf_unaligned);
EXPORT_SYMBOL(fb_sysmove_buf_aligned);
EXPORT_SYMBOL(fb_load_cursor_image);
EXPORT_SYMBOL(fb_set_suspend);
EXPORT_SYMBOL(fb_register_client);
EXPORT_SYMBOL(fb_unregister_client);

MODULE_LICENSE("GPL");