[PATCH] pci: Introduce pci_find_present

[PATCH] pci: Introduce pci_find_present

[Alan]

This works like pci_dev_present but instead of returning boolean returns
the matching pci_device_id entry. This makes it much more useful. Code
bloat is basically nil as the old boolean function is rewritten in terms
of the new one.

This will be used by the updated VIA PCI quirks for one

Signed-off-by: Alan Cox <alan@redhat.com>

diff -u --new-file --recursive --exclude-from /usr/src/exclude linux.vanilla-2.6.19-rc5-mm2/drivers/pci/search.c linux-2.6.19-rc5-mm2/drivers/pci/search.c
--- linux.vanilla-2.6.19-rc5-mm2/drivers/pci/search.c	2006-11-15 13:25:47.000000000 +0000
+++ linux-2.6.19-rc5-mm2/drivers/pci/search.c	2006-11-15 13:52:14.000000000 +0000
@@ -413,6 +413,24 @@
 	return dev;
 }
 
+const struct pci_device_id *pci_find_present(const struct pci_device_id *ids)
+{
+	struct pci_dev *dev;
+	struct pci_device_id * found = NULL;
+
+	WARN_ON(in_interrupt());
+	down_read(&pci_bus_sem);
+	while (ids->vendor || ids->subvendor || ids->class_mask) {
+		list_for_each_entry(dev, &pci_devices, global_list) {
+			if ((found = pci_match_one_device(ids, dev)) != NULL)
+				break;
+		}
+		ids++;
+	}
+	up_read(&pci_bus_sem);
+	return found;
+}
+
 /**
  * pci_dev_present - Returns 1 if device matching the device list is present, 0 if not.
  * @ids: A pointer to a null terminated list of struct pci_device_id structures
@@ -424,27 +442,14 @@
  * find devices that are usually built into a system, or for a general hint as
  * to if another device happens to be present at this specific moment in time.
  */
+
 int pci_dev_present(const struct pci_device_id *ids)
 {
-	struct pci_dev *dev;
-	int found = 0;
-
-	WARN_ON(in_interrupt());
-	down_read(&pci_bus_sem);
-	while (ids->vendor || ids->subvendor || ids->class_mask) {
-		list_for_each_entry(dev, &pci_devices, global_list) {
-			if (pci_match_one_device(ids, dev)) {
-				found = 1;
-				goto exit;
-			}
-		}
-		ids++;
-	}
-exit:
-	up_read(&pci_bus_sem);
-	return found;
+	return pci_find_present(ids) == NULL ? 0 : 1;
 }
+
 EXPORT_SYMBOL(pci_dev_present);
+EXPORT_SYMBOL(pci_find_present);
 
 EXPORT_SYMBOL(pci_find_device);
 EXPORT_SYMBOL(pci_find_device_reverse);
diff -u --new-file --recursive --exclude-from /usr/src/exclude linux.vanilla-2.6.19-rc5-mm2/include/linux/pci.h linux-2.6.19-rc5-mm2/include/linux/pci.h
--- linux.vanilla-2.6.19-rc5-mm2/include/linux/pci.h	2006-11-15 13:27:03.000000000 +0000
+++ linux-2.6.19-rc5-mm2/include/linux/pci.h	2006-11-15 13:53:30.000000000 +0000
@@ -461,6 +476,7 @@
 struct pci_dev *pci_get_bus_and_slot (unsigned int bus, unsigned int devfn);
 struct pci_dev *pci_get_class (unsigned int class, struct pci_dev *from);
 int pci_dev_present(const struct pci_device_id *ids);
+const struct pci_device_id *pci_find_present(const struct pci_device_id *ids);
 
 int pci_bus_read_config_byte (struct pci_bus *bus, unsigned int devfn, int where, u8 *val);
 int pci_bus_read_config_word (struct pci_bus *bus, unsigned int devfn, int where, u16 *val);
@@ -684,6 +700,7 @@
 { return NULL; }
 
 #define pci_dev_present(ids)	(0)
+#define pci_find_present(ids)	(NULL)
 #define pci_dev_put(dev)	do { } while (0)
 
 static inline void pci_set_master(struct pci_dev *dev) { }

Re: [PATCH] pci: Introduce pci_find_present

[Arjan van de Ven]

On Wed, 2006-11-15 at 16:24 +0000, Alan wrote:
> This works like pci_dev_present but instead of returning boolean returns
> the matching pci_device_id entry. This makes it much more useful. Code
> bloat is basically nil as the old boolean function is rewritten in terms
> of the new one.
> 

shouldn't this take a refcount on the device (which the user of this
function then has to put again) ?



-- 
if you want to mail me at work (you don't), use arjan (at) linux.intel.com
Test the interaction between Linux and your BIOS via http://www.linuxfirmwarekit.org

Re: [PATCH] pci: Introduce pci_find_present

[Alan]

On Wed, 15 Nov 2006 17:26:39 +0100
Arjan van de Ven <arjan@infradead.org> wrote:

> On Wed, 2006-11-15 at 16:24 +0000, Alan wrote:
> > This works like pci_dev_present but instead of returning boolean returns
> > the matching pci_device_id entry. This makes it much more useful. Code
> > bloat is basically nil as the old boolean function is rewritten in terms
> > of the new one.
> > 
> 
> shouldn't this take a refcount on the device (which the user of this
> function then has to put again) ?

Nope. It is returning a pci_device_id from an array of pci_device_id
values that were passed into the function. It is not returning a pci
device so it does not require refcounts.

Alan