int pcmcia_request_window()

in pcmcia_resource.c [833:920]

• 70 lines of code
• 17 McCabe index (conditional complexity)

int pcmcia_request_window(struct pcmcia_device *p_dev, struct resource *res,
			unsigned int speed)
{
	struct pcmcia_socket *s = p_dev->socket;
	pccard_mem_map *win;
	u_long align;
	int w;

	dev_dbg(&p_dev->dev, "request_window %pR %d\n", res, speed);

	if (!(s->state & SOCKET_PRESENT)) {
		dev_dbg(&p_dev->dev, "No card present\n");
		return -ENODEV;
	}

	/* Window size defaults to smallest available */
	if (res->end == 0)
		res->end = s->map_size;
	align = (s->features & SS_CAP_MEM_ALIGN) ? res->end : s->map_size;
	if (res->end & (s->map_size-1)) {
		dev_dbg(&p_dev->dev, "invalid map size\n");
		return -EINVAL;
	}
	if ((res->start && (s->features & SS_CAP_STATIC_MAP)) ||
	    (res->start & (align-1))) {
		dev_dbg(&p_dev->dev, "invalid base address\n");
		return -EINVAL;
	}
	if (res->start)
		align = 0;

	/* Allocate system memory window */
	mutex_lock(&s->ops_mutex);
	for (w = 0; w < MAX_WIN; w++)
		if (!(s->state & SOCKET_WIN_REQ(w)))
			break;
	if (w == MAX_WIN) {
		dev_dbg(&p_dev->dev, "all windows are used already\n");
		mutex_unlock(&s->ops_mutex);
		return -EINVAL;
	}

	win = &s->win[w];

	if (!(s->features & SS_CAP_STATIC_MAP)) {
		win->res = pcmcia_find_mem_region(res->start, res->end, align,
						0, s);
		if (!win->res) {
			dev_dbg(&p_dev->dev, "allocating mem region failed\n");
			mutex_unlock(&s->ops_mutex);
			return -EINVAL;
		}
	}
	p_dev->_win |= CLIENT_WIN_REQ(w);

	/* Configure the socket controller */
	win->map = w+1;
	win->flags = res->flags & WIN_FLAGS_MAP;
	win->speed = speed;
	win->card_start = 0;

	if (s->ops->set_mem_map(s, win) != 0) {
		dev_dbg(&p_dev->dev, "failed to set memory mapping\n");
		mutex_unlock(&s->ops_mutex);
		return -EIO;
	}
	s->state |= SOCKET_WIN_REQ(w);

	/* Return window handle */
	if (s->features & SS_CAP_STATIC_MAP)
		res->start = win->static_start;
	else
		res->start = win->res->start;

	/* convert to new-style resources */
	res->end += res->start - 1;
	res->flags &= ~WIN_FLAGS_REQ;
	res->flags |= (win->map << 2) | IORESOURCE_MEM;
	res->parent = win->res;
	if (win->res)
		request_resource(&iomem_resource, res);

	dev_dbg(&p_dev->dev, "request_window results in %pR\n", res);

	mutex_unlock(&s->ops_mutex);

	return 0;
} /* pcmcia_request_window */