fbmem.c

Linux环境下视频显示卡设备的驱动程序源代码

	/* What depth we asked for might be different from what we get */
	if (fb_logo.logo->type == LINUX_LOGO_CLUT224)
		fb_logo.depth = 8;
	else if (fb_logo.logo->type == LINUX_LOGO_VGA16)
		fb_logo.depth = 4;
	else
		fb_logo.depth = 1;


 	if (fb_logo.depth > 4 && depth > 4) {
 		switch (info->fix.visual) {
 		case FB_VISUAL_TRUECOLOR:
 			fb_logo.needs_truepalette = 1;
 			break;
 		case FB_VISUAL_DIRECTCOLOR:
 			fb_logo.needs_directpalette = 1;
 			fb_logo.needs_cmapreset = 1;
 			break;
 		case FB_VISUAL_PSEUDOCOLOR:
 			fb_logo.needs_cmapreset = 1;
 			break;
 		}
 	}

	return fb_prepare_extra_logos(info, fb_logo.logo->height, yres);
}

int fb_show_logo(struct fb_info *info, int rotate)
{
	int y;

	y = fb_show_logo_line(info, rotate, fb_logo.logo, 0,
			      num_online_cpus());
	y = fb_show_extra_logos(info, y, rotate);

	return y;
}
#else
int fb_prepare_logo(struct fb_info *info, int rotate) { return 0; }
int fb_show_logo(struct fb_info *info, int rotate) { return 0; }
#endif /* CONFIG_LOGO */

static void *fb_seq_start(struct seq_file *m, loff_t *pos)
{
	return (*pos < FB_MAX) ? pos : NULL;
}

static void *fb_seq_next(struct seq_file *m, void *v, loff_t *pos)
{
	(*pos)++;
	return (*pos < FB_MAX) ? pos : NULL;
}

static void fb_seq_stop(struct seq_file *m, void *v)
{
}

static int fb_seq_show(struct seq_file *m, void *v)
{
	int i = *(loff_t *)v;
	struct fb_info *fi = registered_fb[i];

	if (fi)
		seq_printf(m, "%d %s\n", fi->node, fi->fix.id);
	return 0;
}

static const struct seq_operations proc_fb_seq_ops = {
	.start	= fb_seq_start,
	.next	= fb_seq_next,
	.stop	= fb_seq_stop,
	.show	= fb_seq_show,
};

static int proc_fb_open(struct inode *inode, struct file *file)
{
	return seq_open(file, &proc_fb_seq_ops);
}

static const struct file_operations fb_proc_fops = {
	.owner		= THIS_MODULE,
	.open		= proc_fb_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= seq_release,
};

static ssize_t
fb_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
{
	unsigned long p = *ppos;
	struct inode *inode = file->f_path.dentry->d_inode;
	int fbidx = iminor(inode);
	struct fb_info *info = registered_fb[fbidx];
	u32 *buffer, *dst;
	u32 __iomem *src;
	int c, i, cnt = 0, err = 0;
	unsigned long total_size;

	if (!info || ! info->screen_base)
		return -ENODEV;

	if (info->state != FBINFO_STATE_RUNNING)
		return -EPERM;

	if (info->fbops->fb_read)
		return info->fbops->fb_read(info, buf, count, ppos);
	
	total_size = info->screen_size;

	if (total_size == 0)
		total_size = info->fix.smem_len;

	if (p >= total_size)
		return 0;

	if (count >= total_size)
		count = total_size;

	if (count + p > total_size)
		count = total_size - p;

	buffer = kmalloc((count > PAGE_SIZE) ? PAGE_SIZE : count,
			 GFP_KERNEL);
	if (!buffer)
		return -ENOMEM;

	src = (u32 __iomem *) (info->screen_base + p);

	if (info->fbops->fb_sync)
		info->fbops->fb_sync(info);

	while (count) {
		c  = (count > PAGE_SIZE) ? PAGE_SIZE : count;
		dst = buffer;
		for (i = c >> 2; i--; )
			*dst++ = fb_readl(src++);
		if (c & 3) {
			u8 *dst8 = (u8 *) dst;
			u8 __iomem *src8 = (u8 __iomem *) src;

			for (i = c & 3; i--;)
				*dst8++ = fb_readb(src8++);

			src = (u32 __iomem *) src8;
		}

		if (copy_to_user(buf, buffer, c)) {
			err = -EFAULT;
			break;
		}
		*ppos += c;
		buf += c;
		cnt += c;
		count -= c;
	}

	kfree(buffer);

	return (err) ? err : cnt;
}

static ssize_t
fb_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
{
	unsigned long p = *ppos;
	struct inode *inode = file->f_path.dentry->d_inode;
	int fbidx = iminor(inode);
	struct fb_info *info = registered_fb[fbidx];
	u32 *buffer, *src;
	u32 __iomem *dst;
	int c, i, cnt = 0, err = 0;
	unsigned long total_size;

	if (!info || !info->screen_base)
		return -ENODEV;

	if (info->state != FBINFO_STATE_RUNNING)
		return -EPERM;

	if (info->fbops->fb_write)
		return info->fbops->fb_write(info, buf, count, ppos);
	
	total_size = info->screen_size;

	if (total_size == 0)
		total_size = info->fix.smem_len;

	if (p > total_size)
		return -EFBIG;

	if (count > total_size) {
		err = -EFBIG;
		count = total_size;
	}

	if (count + p > total_size) {
		if (!err)
			err = -ENOSPC;

		count = total_size - p;
	}

	buffer = kmalloc((count > PAGE_SIZE) ? PAGE_SIZE : count,
			 GFP_KERNEL);
	if (!buffer)
		return -ENOMEM;

	dst = (u32 __iomem *) (info->screen_base + p);

	if (info->fbops->fb_sync)
		info->fbops->fb_sync(info);

	while (count) {
		c = (count > PAGE_SIZE) ? PAGE_SIZE : count;
		src = buffer;

		if (copy_from_user(src, buf, c)) {
			err = -EFAULT;
			break;
		}

		for (i = c >> 2; i--; )
			fb_writel(*src++, dst++);

		if (c & 3) {
			u8 *src8 = (u8 *) src;
			u8 __iomem *dst8 = (u8 __iomem *) dst;

			for (i = c & 3; i--; )
				fb_writeb(*src8++, dst8++);

			dst = (u32 __iomem *) dst8;
		}

		*ppos += c;
		buf += c;
		cnt += c;
		count -= c;
	}

	kfree(buffer);

	return (cnt) ? cnt : err;
}

int
fb_pan_display(struct fb_info *info, struct fb_var_screeninfo *var)
{
	struct fb_fix_screeninfo *fix = &info->fix;
	unsigned int yres = info->var.yres;
	int err = 0;

	if (var->yoffset > 0) {
		if (var->vmode & FB_VMODE_YWRAP) {
			if (!fix->ywrapstep || (var->yoffset % fix->ywrapstep))
				err = -EINVAL;
			else
				yres = 0;
		} else if (!fix->ypanstep || (var->yoffset % fix->ypanstep))
			err = -EINVAL;
	}

	if (var->xoffset > 0 && (!fix->xpanstep ||
				 (var->xoffset % fix->xpanstep)))
		err = -EINVAL;

	if (err || !info->fbops->fb_pan_display ||
	    var->yoffset + yres > info->var.yres_virtual ||
	    var->xoffset + info->var.xres > info->var.xres_virtual)
		return -EINVAL;

	if ((err = info->fbops->fb_pan_display(var, info)))
		return err;
        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;
}

static int fb_check_caps(struct fb_info *info, struct fb_var_screeninfo *var,
			 u32 activate)
{
	struct fb_event event;
	struct fb_blit_caps caps, fbcaps;
	int err = 0;

	memset(&caps, 0, sizeof(caps));
	memset(&fbcaps, 0, sizeof(fbcaps));
	caps.flags = (activate & FB_ACTIVATE_ALL) ? 1 : 0;
	event.info = info;
	event.data = &caps;
	fb_notifier_call_chain(FB_EVENT_GET_REQ, &event);
	info->fbops->fb_get_caps(info, &fbcaps, var);

	if (((fbcaps.x ^ caps.x) & caps.x) ||
	    ((fbcaps.y ^ caps.y) & caps.y) ||
	    (fbcaps.len < caps.len))
		err = -EINVAL;

	return err;
}

int
fb_set_var(struct fb_info *info, struct fb_var_screeninfo *var)
{
	int flags = info->flags;
	int ret = 0;

	if (var->activate & FB_ACTIVATE_INV_MODE) {
		struct fb_videomode mode1, mode2;

		fb_var_to_videomode(&mode1, var);
		fb_var_to_videomode(&mode2, &info->var);
		/* make sure we don't delete the videomode of current var */
		ret = fb_mode_is_equal(&mode1, &mode2);

		if (!ret) {
		    struct fb_event event;

		    event.info = info;
		    event.data = &mode1;
		    ret = fb_notifier_call_chain(FB_EVENT_MODE_DELETE, &event);
		}

		if (!ret)
		    fb_delete_videomode(&mode1, &info->modelist);


		ret = (ret) ? -EINVAL : 0;
		goto done;
	}

	if ((var->activate & FB_ACTIVATE_FORCE) ||
	    memcmp(&info->var, var, sizeof(struct fb_var_screeninfo))) {
		u32 activate = var->activate;

		if (!info->fbops->fb_check_var) {
			*var = info->var;
			goto done;
		}

		ret = info->fbops->fb_check_var(var, info);

		if (ret)
			goto done;

		if ((var->activate & FB_ACTIVATE_MASK) == FB_ACTIVATE_NOW) {
			struct fb_videomode mode;

			if (info->fbops->fb_get_caps) {
				ret = fb_check_caps(info, var, activate);

				if (ret)
					goto done;
			}

			info->var = *var;

			if (info->fbops->fb_set_par)
				info->fbops->fb_set_par(info);

			fb_pan_display(info, &info->var);
			fb_set_cmap(&info->cmap, info);
			fb_var_to_videomode(&mode, &info->var);

			if (info->modelist.prev && info->modelist.next &&
			    !list_empty(&info->modelist))
				ret = fb_add_videomode(&mode, &info->modelist);

			if (!ret && (flags & FBINFO_MISC_USEREVENT)) {
				struct fb_event event;
				int evnt = (activate & FB_ACTIVATE_ALL) ?
					FB_EVENT_MODE_CHANGE_ALL :
					FB_EVENT_MODE_CHANGE;

				info->flags &= ~FBINFO_MISC_USEREVENT;
				event.info = info;
				event.data = &mode;
				fb_notifier_call_chain(evnt, &event);
			}
		}
	}

 done:
	return ret;
}

int
fb_blank(struct fb_info *info, int blank)
{	
 	int ret = -EINVAL;

 	if (blank > FB_BLANK_POWERDOWN)
 		blank = FB_BLANK_POWERDOWN;

	if (info->fbops->fb_blank)
 		ret = info->fbops->fb_blank(blank, info);

 	if (!ret) {
		struct fb_event event;

		event.info = info;
		event.data = &blank;
		fb_notifier_call_chain(FB_EVENT_BLANK, &event);
	}

 	return ret;
}

static long do_fb_ioctl(struct fb_info *info, unsigned int cmd,
			unsigned long arg)
{
	struct fb_ops *fb;
	struct fb_var_screeninfo var;
	struct fb_fix_screeninfo fix;
	struct fb_con2fbmap con2fb;
	struct fb_cmap cmap_from;
	struct fb_cmap_user cmap;
	struct fb_event event;
	void __user *argp = (void __user *)arg;
	long ret = 0;

	switch (cmd) {
	case FBIOGET_VSCREENINFO:
		if (!lock_fb_info(info))
			return -ENODEV;
		var = info->var;
		unlock_fb_info(info);

		ret = copy_to_user(argp, &var, sizeof(var)) ? -EFAULT : 0;
		break;
	case FBIOPUT_VSCREENINFO:
		if (copy_from_user(&var, argp, sizeof(var)))
			return -EFAULT;
		if (!lock_fb_info(info))
			return -ENODEV;
		acquire_console_sem();
		info->flags |= FBINFO_MISC_USEREVENT;
		ret = fb_set_var(info, &var);
		info->flags &= ~FBINFO_MISC_USEREVENT;
		release_console_sem();
		unlock_fb_info(info);
		if (!ret && copy_to_user(argp, &var, sizeof(var)))
			ret = -EFAULT;
		break;
	case FBIOGET_FSCREENINFO:
		if (!lock_fb_info(info))
			return -ENODEV;
		fix = info->fix;
		unlock_fb_info(info);

		ret = copy_to_user(argp, &fix, sizeof(fix)) ? -EFAULT : 0;
		break;
	case FBIOPUTCMAP:
		if (copy_from_user(&cmap, argp, sizeof(cmap)))
			return -EFAULT;
		ret = fb_set_user_cmap(&cmap, info);
		break;
	case FBIOGETCMAP:
		if (copy_from_user(&cmap, argp, sizeof(cmap)))
			return -EFAULT;
		if (!lock_fb_info(info))
			return -ENODEV;
		cmap_from = info->cmap;
		unlock_fb_info(info);
		ret = fb_cmap_to_user(&cmap_from, &cmap);
		break;
	case FBIOPAN_DISPLAY:
		if (copy_from_user(&var, argp, sizeof(var)))
			return -EFAULT;
		if (!lock_fb_info(info))
			return -ENODEV;
		acquire_console_sem();
		ret = fb_pan_display(info, &var);
		release_console_sem();
		unlock_fb_info(info);
		if (ret == 0 && copy_to_user(argp, &var, sizeof(var)))
			return -EFAULT;
		break;
	case FBIO_CURSOR:
		ret = -EINVAL;
		break;
	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 = -1;
		event.data = &con2fb;

		if (!lock_fb_info(info))
			return -ENODEV;
		event.info = info;
		fb_notifier_call_chain(FB_EVENT_GET_CONSOLE_MAP, &event);
		unlock_fb_info(info);

		ret = copy_to_user(argp, &con2fb, sizeof(con2fb)) ? -EFAULT : 0;
		break;
	case FBIOPUT_CON2FBMAP:
		if (copy_from_user(&con2fb, argp, sizeof(con2fb)))
			return -EFAULT;
		if (con2fb.console < 1 || con2fb.console > MAX_NR_CONSOLES)
			return -EINVAL;
		if (con2fb.framebuffer < 0 || con2fb.framebuffer >= FB_MAX)
			return -EINVAL;
		if (!registered_fb[con2fb.framebuffer])
			request_module("fb%d", con2fb.framebuffer);
		if (!registered_fb[con2fb.framebuffer]) {
			ret = -EINVAL;
			break;
		}
		event.data = &con2fb;
		if (!lock_fb_info(info))
			return -ENODEV;
		event.info = info;
		ret = fb_notifier_call_chain(FB_EVENT_SET_CONSOLE_MAP,
					      &event);
		unlock_fb_info(info);
		break;
	case FBIOBLANK:
		if (!lock_fb_info(info))
			return -ENODEV;
		acquire_console_sem();
		info->flags |= FBINFO_MISC_USEREVENT;
		ret = fb_blank(info, arg);
		info->flags &= ~FBINFO_MISC_USEREVENT;
		release_console_sem();
		unlock_fb_info(info);
		break;
	default:
		if (!lock_fb_info(info))
			return -ENODEV;
		fb = info->fbops;
		if (fb->fb_ioctl)
			ret = fb->fb_ioctl(info, cmd, arg);
		else
			ret = -ENOTTY;
		unlock_fb_info(info);
	}
	return ret;
}

static long fb_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
	struct inode *inode = file->f_path.dentry->d_inode;
	int fbidx = iminor(inode);
	struct fb_info *info = registered_fb[fbidx];

	return do_fb_ioctl(info, cmd, arg);
}

#ifdef CONFIG_COMPAT
struct fb_fix_screeninfo32 {
	char			id[16];
	compat_caddr_t		smem_start;
	u32			smem_len;
	u32			type;
	u32			type_aux;
	u32			visual;
	u16			xpanstep;
	u16			ypanstep;
	u16			ywrapstep;
	u32			line_length;
	compat_caddr_t		mmio_start;
	u32			mmio_len;
	u32			accel;
	u16			reserved[3];
};

struct fb_cmap32 {
	u32			start;
	u32			len;
	compat_caddr_t	red;
	compat_caddr_t	green;
	compat_caddr_t	blue;
	compat_caddr_t	transp;
};

static int fb_getput_cmap(struct fb_info *info, unsigned int cmd,
			  unsigned long arg)
{
	struct fb_cmap_user __user *cmap;
	struct fb_cmap32 __user *cmap32;
	__u32 data;
	int err;

	cmap = compat_alloc_user_space(sizeof(*cmap));
	cmap32 = compat_ptr(arg);