arcfb.c

Linux环境下视频显示卡设备的驱动程序源代码

	}
}

/*
 * here we start the process of spliting out the fb update into
 * individual blocks of pixels. we end up spliting into 64x64 blocks
 * and finally down to 64x8 pages.
 */
static void arcfb_lcd_update(struct arcfb_par *par, unsigned int dx,
			unsigned int dy, unsigned int w, unsigned int h)
{
	unsigned int left, right, distance, y;

	/* align the request first */
	y = floor8(dy);
	h += dy - y;
	h = iceil8(h);

	distance = w;
	left = dx;
	right = min(left + w - 1, ceil64(left));

	while (distance > 0) {
		arcfb_lcd_update_horiz(par, left, right, y, h);
		distance -= ((right - left) + 1);
		left = right + 1;
		right = min(left + distance - 1, ceil64(left));
	}
}

static void arcfb_fillrect(struct fb_info *info,
			   const struct fb_fillrect *rect)
{
	struct arcfb_par *par = info->par;

	sys_fillrect(info, rect);

	/* update the physical lcd */
	arcfb_lcd_update(par, rect->dx, rect->dy, rect->width, rect->height);
}

static void arcfb_copyarea(struct fb_info *info,
			   const struct fb_copyarea *area)
{
	struct arcfb_par *par = info->par;

	sys_copyarea(info, area);

	/* update the physical lcd */
	arcfb_lcd_update(par, area->dx, area->dy, area->width, area->height);
}

static void arcfb_imageblit(struct fb_info *info, const struct fb_image *image)
{
	struct arcfb_par *par = info->par;

	sys_imageblit(info, image);

	/* update the physical lcd */
	arcfb_lcd_update(par, image->dx, image->dy, image->width,
				image->height);
}

static int arcfb_ioctl(struct fb_info *info,
			  unsigned int cmd, unsigned long arg)
{
	void __user *argp = (void __user *)arg;
	struct arcfb_par *par = info->par;
	unsigned long flags;

	switch (cmd) {
		case FBIO_WAITEVENT:
		{
			DEFINE_WAIT(wait);
			/* illegal to wait on arc if no irq will occur */
			if (!par->irq)
				return -EINVAL;

			/* wait until the Arc has generated an interrupt
			 * which will wake us up */
			spin_lock_irqsave(&par->lock, flags);
			prepare_to_wait(&arcfb_waitq, &wait,
					TASK_INTERRUPTIBLE);
			spin_unlock_irqrestore(&par->lock, flags);
			schedule();
			finish_wait(&arcfb_waitq, &wait);
		}
		case FBIO_GETCONTROL2:
		{
			unsigned char ctl2;

			ctl2 = ks108_readb_ctl2(info->par);
			if (copy_to_user(argp, &ctl2, sizeof(ctl2)))
				return -EFAULT;
			return 0;
		}
		default:
			return -EINVAL;
	}
}

/*
 * this is the access path from userspace. they can seek and write to
 * the fb. it's inefficient for them to do anything less than 64*8
 * writes since we update the lcd in each write() anyway.
 */
static ssize_t arcfb_write(struct fb_info *info, const char __user *buf,
			   size_t count, loff_t *ppos)
{
	/* modded from epson 1355 */

	unsigned long p;
	int err=-EINVAL;
	unsigned int fbmemlength,x,y,w,h, bitppos, startpos, endpos, bitcount;
	struct arcfb_par *par;
	unsigned int xres;

	p = *ppos;
	par = info->par;
	xres = info->var.xres;
	fbmemlength = (xres * info->var.yres)/8;

	if (p > fbmemlength)
		return -ENOSPC;

	err = 0;
	if ((count + p) > fbmemlength) {
		count = fbmemlength - p;
		err = -ENOSPC;
	}

	if (count) {
		char *base_addr;

		base_addr = (char __force *)info->screen_base;
		count -= copy_from_user(base_addr + p, buf, count);
		*ppos += count;
		err = -EFAULT;
	}


	bitppos = p*8;
	startpos = floorXres(bitppos, xres);
	endpos = ceilXres((bitppos + (count*8)), xres);
	bitcount = endpos - startpos;

	x = startpos % xres;
	y = startpos / xres;
	w = xres;
	h = bitcount / xres;
	arcfb_lcd_update(par, x, y, w, h);

	if (count)
		return count;
	return err;
}

static struct fb_ops arcfb_ops = {
	.owner		= THIS_MODULE,
	.fb_open	= arcfb_open,
	.fb_read        = fb_sys_read,
	.fb_write	= arcfb_write,
	.fb_release	= arcfb_release,
	.fb_pan_display	= arcfb_pan_display,
	.fb_fillrect	= arcfb_fillrect,
	.fb_copyarea	= arcfb_copyarea,
	.fb_imageblit	= arcfb_imageblit,
	.fb_ioctl 	= arcfb_ioctl,
};

static int __init arcfb_probe(struct platform_device *dev)
{
	struct fb_info *info;
	int retval = -ENOMEM;
	int videomemorysize;
	unsigned char *videomemory;
	struct arcfb_par *par;
	int i;

	videomemorysize = (((64*64)*num_cols)*num_rows)/8;

	/* We need a flat backing store for the Arc's
	   less-flat actual paged framebuffer */
	if (!(videomemory = vmalloc(videomemorysize)))
		return retval;

	memset(videomemory, 0, videomemorysize);

	info = framebuffer_alloc(sizeof(struct arcfb_par), &dev->dev);
	if (!info)
		goto err;

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

	info->var = arcfb_var;
	info->fix = arcfb_fix;
	par = info->par;
	par->info = info;

	if (!dio_addr || !cio_addr || !c2io_addr) {
		printk(KERN_WARNING "no IO addresses supplied\n");
		goto err1;
	}
	par->dio_addr = dio_addr;
	par->cio_addr = cio_addr;
	par->c2io_addr = c2io_addr;
	par->cslut[0] = 0x00;
	par->cslut[1] = 0x06;
	info->flags = FBINFO_FLAG_DEFAULT;
	spin_lock_init(&par->lock);
	retval = register_framebuffer(info);
	if (retval < 0)
		goto err1;
	platform_set_drvdata(dev, info);
	if (irq) {
		par->irq = irq;
		if (request_irq(par->irq, &arcfb_interrupt, IRQF_SHARED,
				"arcfb", info)) {
			printk(KERN_INFO
				"arcfb: Failed req IRQ %d\n", par->irq);
			goto err1;
		}
	}
	printk(KERN_INFO
	       "fb%d: Arc frame buffer device, using %dK of video memory\n",
	       info->node, videomemorysize >> 10);

	/* this inits the lcd but doesn't clear dirty pixels */
	for (i = 0; i < num_cols * num_rows; i++) {
		ks108_writeb_ctl(par, i, KS_DPY_OFF);
		ks108_set_start_line(par, i, 0);
		ks108_set_yaddr(par, i, 0);
		ks108_set_xaddr(par, i, 0);
		ks108_writeb_ctl(par, i, KS_DPY_ON);
	}

	/* if we were told to splash the screen, we just clear it */
	if (!nosplash) {
		for (i = 0; i < num_cols * num_rows; i++) {
			printk(KERN_INFO "fb%d: splashing lcd %d\n",
				info->node, i);
			ks108_set_start_line(par, i, 0);
			ks108_clear_lcd(par, i);
		}
	}

	return 0;
err1:
	framebuffer_release(info);
err:
	vfree(videomemory);
	return retval;
}

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

	if (info) {
		unregister_framebuffer(info);
		vfree((void __force *)info->screen_base);
		framebuffer_release(info);
	}
	return 0;
}

static struct platform_driver arcfb_driver = {
	.probe	= arcfb_probe,
	.remove = arcfb_remove,
	.driver	= {
		.name	= "arcfb",
	},
};

static struct platform_device *arcfb_device;

static int __init arcfb_init(void)
{
	int ret;

	if (!arcfb_enable)
		return -ENXIO;

	ret = platform_driver_register(&arcfb_driver);
	if (!ret) {
		arcfb_device = platform_device_alloc("arcfb", 0);
		if (arcfb_device) {
			ret = platform_device_add(arcfb_device);
		} else {
			ret = -ENOMEM;
		}
		if (ret) {
			platform_device_put(arcfb_device);
			platform_driver_unregister(&arcfb_driver);
		}
	}
	return ret;

}

static void __exit arcfb_exit(void)
{
	platform_device_unregister(arcfb_device);
	platform_driver_unregister(&arcfb_driver);
}

module_param(num_cols, ulong, 0);
MODULE_PARM_DESC(num_cols, "Num horiz panels, eg: 2 = 128 bit wide");
module_param(num_rows, ulong, 0);
MODULE_PARM_DESC(num_rows, "Num vert panels, eg: 1 = 64 bit high");
module_param(nosplash, uint, 0);
MODULE_PARM_DESC(nosplash, "Disable doing the splash screen");
module_param(arcfb_enable, uint, 0);
MODULE_PARM_DESC(arcfb_enable, "Enable communication with Arc board");
module_param(dio_addr, ulong, 0);
MODULE_PARM_DESC(dio_addr, "IO address for data, eg: 0x480");
module_param(cio_addr, ulong, 0);
MODULE_PARM_DESC(cio_addr, "IO address for control, eg: 0x400");
module_param(c2io_addr, ulong, 0);
MODULE_PARM_DESC(c2io_addr, "IO address for secondary control, eg: 0x408");
module_param(splashval, ulong, 0);
MODULE_PARM_DESC(splashval, "Splash pattern: 0xFF is black, 0x00 is green");
module_param(tuhold, ulong, 0);
MODULE_PARM_DESC(tuhold, "Time to hold between strobing data to Arc board");
module_param(irq, uint, 0);
MODULE_PARM_DESC(irq, "IRQ for the Arc board");

module_init(arcfb_init);
module_exit(arcfb_exit);

MODULE_DESCRIPTION("fbdev driver for Arc monochrome LCD board");
MODULE_AUTHOR("Jaya Kumar");
MODULE_LICENSE("GPL");