[PATCH] Hotplug parallel ports

The Mobility docking station provides a PCI-based parallel port.  Since the
docking station connects via Cardbus, such devices are removable. 
Therefore, track which parallel ports are registered to each PCI device,
and remove them when the PCI device is removed.
Signed-off-by: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

drivers/parport/parport_pc.c

@@ -2907,10 +2907,16 @@ static struct pci_device_id parport_pc_pci_tbl[] = {
 };
 MODULE_DEVICE_TABLE(pci,parport_pc_pci_tbl);
 
+struct pci_parport_data {
+	int num;
+	struct parport *ports[2];
+};
+
 static int parport_pc_pci_probe (struct pci_dev *dev,
 					   const struct pci_device_id *id)
 {
 	int err, count, n, i = id->driver_data;
+	struct pci_parport_data *data;
 
 	if (i < last_sio)
 		/* This is an onboard Super-IO and has already been probed */
@@ -2922,9 +2928,15 @@ static int parport_pc_pci_probe (struct pci_dev *dev,
 	if ((err = pci_enable_device (dev)) != 0)
 		return err;
 
+	data = kmalloc(sizeof(struct pci_parport_data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
 	if (cards[i].preinit_hook &&
-	    cards[i].preinit_hook (dev, PARPORT_IRQ_NONE, PARPORT_DMA_NONE))
+	    cards[i].preinit_hook (dev, PARPORT_IRQ_NONE, PARPORT_DMA_NONE)) {
+		kfree(data);
 		return -ENODEV;
+	}
 
 	for (n = 0; n < cards[i].numports; n++) {
 		int lo = cards[i].addr[n].lo;
@@ -2943,21 +2955,46 @@ static int parport_pc_pci_probe (struct pci_dev *dev,
 			"I/O at %#lx(%#lx)\n",
 			parport_pc_pci_tbl[i + last_sio].vendor,
 			parport_pc_pci_tbl[i + last_sio].device, io_lo, io_hi);
-		if (parport_pc_probe_port (io_lo, io_hi, PARPORT_IRQ_NONE,
-					   PARPORT_DMA_NONE, dev))
+		data->ports[count] =
+			parport_pc_probe_port (io_lo, io_hi, PARPORT_IRQ_NONE,
+					       PARPORT_DMA_NONE, dev);
+		if (data->ports[count])
 			count++;
 	}
 
+	data->num = count;
+
 	if (cards[i].postinit_hook)
 		cards[i].postinit_hook (dev, count == 0);
 
-	return count == 0 ? -ENODEV : 0;
+	if (count) {
+		pci_set_drvdata(dev, data);
+		return 0;
+	}
+
+	kfree(data);
+
+	return -ENODEV;
+}
+
+static void __devexit parport_pc_pci_remove(struct pci_dev *dev)
+{
+	struct pci_parport_data *data = pci_get_drvdata(dev);
+	int i;
+
+	pci_set_drvdata(dev, NULL);
+
+	for (i = data->num - 1; i >= 0; i--)
+		parport_pc_unregister_port(data->ports[i]);
+
+	kfree(data);
 }
 
 static struct pci_driver parport_pc_pci_driver = {
 	.name		= "parport_pc",
 	.id_table	= parport_pc_pci_tbl,
 	.probe		= parport_pc_pci_probe,
+	.remove		= __devexit_p(parport_pc_pci_remove),
 };
 
 static int __init parport_pc_init_superio (int autoirq, int autodma)