raw3270.c

linux-2.6.15.6

			if (!oldview || oldview->fn->activate(oldview) != 0) {
				/* Didn't work as well. Try any other view. */
				list_for_each_entry(nv, &rp->view_list, list)
					if (nv != view && nv != oldview) {
						rp->view = nv;
						if (nv->fn->activate(nv) == 0)
							break;
						rp->view = 0;
					}
			}
		}
	}
	spin_unlock_irqrestore(get_ccwdev_lock(rp->cdev), flags);
	return rc;
}

/*
 * Deactivate current view.
 */
void
raw3270_deactivate_view(struct raw3270_view *view)
{
	unsigned long flags;
	struct raw3270 *rp;

	rp = view->dev;
	if (!rp)
		return;
	spin_lock_irqsave(get_ccwdev_lock(rp->cdev), flags);
	if (rp->view == view) {
		view->fn->deactivate(view);
		rp->view = 0;
		/* Move deactivated view to end of list. */
		list_del_init(&view->list);
		list_add_tail(&view->list, &rp->view_list);
		/* Try to activate another view. */
		if (test_bit(RAW3270_FLAGS_READY, &rp->flags)) {
			list_for_each_entry(view, &rp->view_list, list) {
				rp->view = view;
				if (view->fn->activate(view) == 0)
					break;
				rp->view = 0;
			}
		}
	}
	spin_unlock_irqrestore(get_ccwdev_lock(rp->cdev), flags);
}

/*
 * Add view to device with minor "minor".
 */
int
raw3270_add_view(struct raw3270_view *view, struct raw3270_fn *fn, int minor)
{
	unsigned long flags;
	struct raw3270 *rp;
	int rc;

	if (minor <= 0)
		return -ENODEV;
	down(&raw3270_sem);
	rc = -ENODEV;
	list_for_each_entry(rp, &raw3270_devices, list) {
		if (rp->minor != minor)
			continue;
		spin_lock_irqsave(get_ccwdev_lock(rp->cdev), flags);
		if (test_bit(RAW3270_FLAGS_READY, &rp->flags)) {
			atomic_set(&view->ref_count, 2);
			view->dev = rp;
			view->fn = fn;
			view->model = rp->model;
			view->rows = rp->rows;
			view->cols = rp->cols;
			view->ascebc = rp->ascebc;
			spin_lock_init(&view->lock);
			list_add(&view->list, &rp->view_list);
			rc = 0;
		}
		spin_unlock_irqrestore(get_ccwdev_lock(rp->cdev), flags);
		break;
	}
	up(&raw3270_sem);
	return rc;
}

/*
 * Find specific view of device with minor "minor".
 */
struct raw3270_view *
raw3270_find_view(struct raw3270_fn *fn, int minor)
{
	struct raw3270 *rp;
	struct raw3270_view *view, *tmp;
	unsigned long flags;

	down(&raw3270_sem);
	view = ERR_PTR(-ENODEV);
	list_for_each_entry(rp, &raw3270_devices, list) {
		if (rp->minor != minor)
			continue;
		spin_lock_irqsave(get_ccwdev_lock(rp->cdev), flags);
		if (test_bit(RAW3270_FLAGS_READY, &rp->flags)) {
			view = ERR_PTR(-ENOENT);
			list_for_each_entry(tmp, &rp->view_list, list) {
				if (tmp->fn == fn) {
					raw3270_get_view(tmp);
					view = tmp;
					break;
				}
			}
		}
		spin_unlock_irqrestore(get_ccwdev_lock(rp->cdev), flags);
		break;
	}
	up(&raw3270_sem);
	return view;
}

/*
 * Remove view from device and free view structure via call to view->fn->free.
 */
void
raw3270_del_view(struct raw3270_view *view)
{
	unsigned long flags;
	struct raw3270 *rp;
	struct raw3270_view *nv;

	rp = view->dev;
	spin_lock_irqsave(get_ccwdev_lock(rp->cdev), flags);
	if (rp->view == view) {
		view->fn->deactivate(view);
		rp->view = 0;
	}
	list_del_init(&view->list);
	if (!rp->view && test_bit(RAW3270_FLAGS_READY, &rp->flags)) {
		/* Try to activate another view. */
		list_for_each_entry(nv, &rp->view_list, list) {
			if (nv->fn->activate(nv) == 0) {
				rp->view = nv;
				break;
			}
		}
	}
	spin_unlock_irqrestore(get_ccwdev_lock(rp->cdev), flags);
	/* Wait for reference counter to drop to zero. */
	atomic_dec(&view->ref_count);
	wait_event(raw3270_wait_queue, atomic_read(&view->ref_count) == 0);
	if (view->fn->free)
		view->fn->free(view);
}

/*
 * Remove a 3270 device structure.
 */
static void
raw3270_delete_device(struct raw3270 *rp)
{
	struct ccw_device *cdev;

	/* Remove from device chain. */
	down(&raw3270_sem);
	if (rp->clttydev)
		class_device_destroy(class3270,
				     MKDEV(IBM_TTY3270_MAJOR, rp->minor));
	if (rp->cltubdev)
		class_device_destroy(class3270,
				     MKDEV(IBM_FS3270_MAJOR, rp->minor));
	list_del_init(&rp->list);
	up(&raw3270_sem);

	/* Disconnect from ccw_device. */
	cdev = rp->cdev;
	rp->cdev = 0;
	cdev->dev.driver_data = 0;
	cdev->handler = 0;

	/* Put ccw_device structure. */
	put_device(&cdev->dev);

	/* Now free raw3270 structure. */
	kfree(rp->ascebc);
	kfree(rp);
}

static int
raw3270_probe (struct ccw_device *cdev)
{
	return 0;
}

/*
 * Additional attributes for a 3270 device
 */
static ssize_t
raw3270_model_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	return snprintf(buf, PAGE_SIZE, "%i\n",
			((struct raw3270 *) dev->driver_data)->model);
}
static DEVICE_ATTR(model, 0444, raw3270_model_show, 0);

static ssize_t
raw3270_rows_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	return snprintf(buf, PAGE_SIZE, "%i\n",
			((struct raw3270 *) dev->driver_data)->rows);
}
static DEVICE_ATTR(rows, 0444, raw3270_rows_show, 0);

static ssize_t
raw3270_columns_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	return snprintf(buf, PAGE_SIZE, "%i\n",
			((struct raw3270 *) dev->driver_data)->cols);
}
static DEVICE_ATTR(columns, 0444, raw3270_columns_show, 0);

static struct attribute * raw3270_attrs[] = {
	&dev_attr_model.attr,
	&dev_attr_rows.attr,
	&dev_attr_columns.attr,
	NULL,
};

static struct attribute_group raw3270_attr_group = {
	.attrs = raw3270_attrs,
};

static void
raw3270_create_attributes(struct raw3270 *rp)
{
	//FIXME: check return code
	sysfs_create_group(&rp->cdev->dev.kobj, &raw3270_attr_group);
	rp->clttydev =
		class_device_create(class3270, NULL,
				    MKDEV(IBM_TTY3270_MAJOR, rp->minor),
				    &rp->cdev->dev, "tty%s",
				    rp->cdev->dev.bus_id);
	rp->cltubdev =
		class_device_create(class3270, NULL,
				    MKDEV(IBM_FS3270_MAJOR, rp->minor),
				    &rp->cdev->dev, "tub%s",
				    rp->cdev->dev.bus_id);
}

/*
 * Notifier for device addition/removal
 */
struct raw3270_notifier {
	struct list_head list;
	void (*notifier)(int, int);
};

static struct list_head raw3270_notifier = LIST_HEAD_INIT(raw3270_notifier);

int raw3270_register_notifier(void (*notifier)(int, int))
{
	struct raw3270_notifier *np;
	struct raw3270 *rp;

	np = kmalloc(sizeof(struct raw3270_notifier), GFP_KERNEL);
	if (!np)
		return -ENOMEM;
	np->notifier = notifier;
	down(&raw3270_sem);
	list_add_tail(&np->list, &raw3270_notifier);
	list_for_each_entry(rp, &raw3270_devices, list) {
		get_device(&rp->cdev->dev);
		notifier(rp->minor, 1);
	}
	up(&raw3270_sem);
	return 0;
}

void raw3270_unregister_notifier(void (*notifier)(int, int))
{
	struct raw3270_notifier *np;

	down(&raw3270_sem);
	list_for_each_entry(np, &raw3270_notifier, list)
		if (np->notifier == notifier) {
			list_del(&np->list);
			kfree(np);
			break;
		}
	up(&raw3270_sem);
}

/*
 * Set 3270 device online.
 */
static int
raw3270_set_online (struct ccw_device *cdev)
{
	struct raw3270 *rp;
	struct raw3270_notifier *np;
	int rc;

	rp = raw3270_create_device(cdev);
	if (IS_ERR(rp))
		return PTR_ERR(rp);
	rc = raw3270_reset_device(rp);
	if (rc)
		goto failure;
	rc = raw3270_size_device(rp);
	if (rc)
		goto failure;
	rc = raw3270_reset_device(rp);
	if (rc)
		goto failure;
	raw3270_create_attributes(rp);
	set_bit(RAW3270_FLAGS_READY, &rp->flags);
	down(&raw3270_sem);
	list_for_each_entry(np, &raw3270_notifier, list)
		np->notifier(rp->minor, 1);
	up(&raw3270_sem);
	return 0;

failure:
	raw3270_delete_device(rp);
	return rc;
}

/*
 * Remove 3270 device structure.
 */
static void
raw3270_remove (struct ccw_device *cdev)
{
	unsigned long flags;
	struct raw3270 *rp;
	struct raw3270_view *v;
	struct raw3270_notifier *np;

	rp = cdev->dev.driver_data;
	/*
	 * _remove is the opposite of _probe; it's probe that
	 * should set up rp.  raw3270_remove gets entered for
	 * devices even if they haven't been varied online.
	 * Thus, rp may validly be NULL here.
	 */
	if (rp == NULL)
		return;
	clear_bit(RAW3270_FLAGS_READY, &rp->flags);

	sysfs_remove_group(&cdev->dev.kobj, &raw3270_attr_group);

	/* Deactivate current view and remove all views. */
	spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
	if (rp->view) {
		rp->view->fn->deactivate(rp->view);
		rp->view = 0;
	}
	while (!list_empty(&rp->view_list)) {
		v = list_entry(rp->view_list.next, struct raw3270_view, list);
		if (v->fn->release)
			v->fn->release(v);
		spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
		raw3270_del_view(v);
		spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
	}
	spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);

	down(&raw3270_sem);
	list_for_each_entry(np, &raw3270_notifier, list)
		np->notifier(rp->minor, 0);
	up(&raw3270_sem);

	/* Reset 3270 device. */
	raw3270_reset_device(rp);
	/* And finally remove it. */
	raw3270_delete_device(rp);
}

/*
 * Set 3270 device offline.
 */
static int
raw3270_set_offline (struct ccw_device *cdev)
{
	struct raw3270 *rp;

	rp = cdev->dev.driver_data;
	if (test_bit(RAW3270_FLAGS_CONSOLE, &rp->flags))
		return -EBUSY;
	raw3270_remove(cdev);
	return 0;
}

static struct ccw_device_id raw3270_id[] = {
	{ CCW_DEVICE(0x3270, 0) },
	{ CCW_DEVICE(0x3271, 0) },
	{ CCW_DEVICE(0x3272, 0) },
	{ CCW_DEVICE(0x3273, 0) },
	{ CCW_DEVICE(0x3274, 0) },
	{ CCW_DEVICE(0x3275, 0) },
	{ CCW_DEVICE(0x3276, 0) },
	{ CCW_DEVICE(0x3277, 0) },
	{ CCW_DEVICE(0x3278, 0) },
	{ CCW_DEVICE(0x3279, 0) },
	{ CCW_DEVICE(0x3174, 0) },
	{ /* end of list */ },
};

static struct ccw_driver raw3270_ccw_driver = {
	.name		= "3270",
	.owner		= THIS_MODULE,
	.ids		= raw3270_id,
	.probe		= &raw3270_probe,
	.remove		= &raw3270_remove,
	.set_online	= &raw3270_set_online,
	.set_offline	= &raw3270_set_offline,
};

static int
raw3270_init(void)
{
	struct raw3270 *rp;
	int rc;

	if (raw3270_registered)
		return 0;
	raw3270_registered = 1;
	rc = ccw_driver_register(&raw3270_ccw_driver);
	if (rc == 0) {
		/* Create attributes for early (= console) device. */
		down(&raw3270_sem);
		class3270 = class_create(THIS_MODULE, "3270");
		list_for_each_entry(rp, &raw3270_devices, list) {
			get_device(&rp->cdev->dev);
			raw3270_create_attributes(rp);
		}
		up(&raw3270_sem);
	}
	return rc;
}

static void
raw3270_exit(void)
{
	ccw_driver_unregister(&raw3270_ccw_driver);
	class_destroy(class3270);
}

MODULE_LICENSE("GPL");

module_init(raw3270_init);
module_exit(raw3270_exit);

EXPORT_SYMBOL(raw3270_request_alloc);
EXPORT_SYMBOL(raw3270_request_free);
EXPORT_SYMBOL(raw3270_request_reset);
EXPORT_SYMBOL(raw3270_request_set_cmd);
EXPORT_SYMBOL(raw3270_request_add_data);
EXPORT_SYMBOL(raw3270_request_set_data);
EXPORT_SYMBOL(raw3270_request_set_idal);
EXPORT_SYMBOL(raw3270_buffer_address);
EXPORT_SYMBOL(raw3270_add_view);
EXPORT_SYMBOL(raw3270_del_view);
EXPORT_SYMBOL(raw3270_find_view);
EXPORT_SYMBOL(raw3270_activate_view);
EXPORT_SYMBOL(raw3270_deactivate_view);
EXPORT_SYMBOL(raw3270_start);
EXPORT_SYMBOL(raw3270_start_locked);
EXPORT_SYMBOL(raw3270_start_irq);
EXPORT_SYMBOL(raw3270_reset);
EXPORT_SYMBOL(raw3270_register_notifier);
EXPORT_SYMBOL(raw3270_unregister_notifier);
EXPORT_SYMBOL(raw3270_wait_queue);