Staging: comedi: s626: use subvendor:subdevice ids for SAA7146 board

The current s626 comedi driver in staging conflicts with philips SAA7146
media/dvb based cards, because it claims the same vendor:device pci id
for all subdevice/subvendor ids. What happens is that for people that have a
philips SAA7146 media/dvb based card, s626 if available gets loaded by udev
and makes system freeze (https://qa.mandriva.com/show_bug.cgi?id=51445).

The s626 driver shouldn't claim all 1131:7146 devices. Fix this by
specifying specific known subvendor:subdevice ids in its pci id table
list.

Also s626_attach is modified to use now pci_get_subsys instead of
pci_get_device as reported by Ian Abbott, and now we loop over pci id
table entries in case more ids are added in the future.

Reference: http://lkml.org/lkml/2009/6/16/552Signed-off-by: Herton Ronaldo Krzesinski <herton@mandriva.com.br>
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/comedi/drivers/s626.c

@@ -111,9 +111,13 @@ static const struct s626_board s626_boards[] = {
 #define PCI_VENDOR_ID_S626 0x1131
 #define PCI_DEVICE_ID_S626 0x7146
 
+/*
+ * For devices with vendor:device id == 0x1131:0x7146 you must specify
+ * also subvendor:subdevice ids, because otherwise it will conflict with
+ * Philips SAA7146 media/dvb based cards.
+ */
 static DEFINE_PCI_DEVICE_TABLE(s626_pci_table) = {
-	{PCI_VENDOR_ID_S626, PCI_DEVICE_ID_S626, PCI_ANY_ID, PCI_ANY_ID, 0, 0,
-		0},
+	{PCI_VENDOR_ID_S626, PCI_DEVICE_ID_S626, 0x6000, 0x0272, 0, 0, 0},
 	{0}
 };
 
@@ -499,25 +503,26 @@ static int s626_attach(struct comedi_device *dev, struct comedi_devconfig *it)
 	resource_size_t resourceStart;
 	dma_addr_t appdma;
 	struct comedi_subdevice *s;
-	struct pci_dev *pdev;
+	const struct pci_device_id *ids;
+	struct pci_dev *pdev = NULL;
 
 	if (alloc_private(dev, sizeof(struct s626_private)) < 0)
 		return -ENOMEM;
 
-	for (pdev = pci_get_device(PCI_VENDOR_ID_S626, PCI_DEVICE_ID_S626,
-			NULL); pdev != NULL;
-		pdev = pci_get_device(PCI_VENDOR_ID_S626,
-			PCI_DEVICE_ID_S626, pdev)) {
-		if (it->options[0] || it->options[1]) {
-			if (pdev->bus->number == it->options[0] &&
-				PCI_SLOT(pdev->devfn) == it->options[1]) {
+	for (i = 0; i < (ARRAY_SIZE(s626_pci_table) - 1) && !pdev; i++) {
+		ids = &s626_pci_table[i];
+		do {
+			pdev = pci_get_subsys(ids->vendor, ids->device, ids->subvendor,
+					      ids->subdevice, pdev);
+
+			if ((it->options[0] || it->options[1]) && pdev) {
 				/* matches requested bus/slot */
+				if (pdev->bus->number == it->options[0] &&
+				    PCI_SLOT(pdev->devfn) == it->options[1])
 					break;
-			}
-		} else {
-			/* no bus/slot specified */
+			} else
 				break;
-		}
+		} while (1);
 	}
 	devpriv->pdev = pdev;