Subject: [PATCH] [acpi driver model] Add support for drivers' ->d_probe() in matching code.

- Call ->d_probe() if we find a match of a device's ID and one of the driver's
  ID.
  The dummy ->d_probe() will always return 1, verifying the match. If it's
  implemented, it will return 0, telling us that it's not really a match.
- If the driver doesn't support any IDs, only call ->d_probe() which
  returns whether or not the device is supported.

Signed-off-by: Patrick Mochel <mochel@linux.intel.com>

---

 drivers/acpi/drivers/core/bus.c |   59 ++++++++++++++++++++++++++++++++-------
 1 files changed, 48 insertions(+), 11 deletions(-)

applies-to: 314093f6e8559e4378a3dc31ced4f01c84c3a840
3f9e72e7e3b52169276dadb54ca4b7f97f1dbef4
diff --git a/drivers/acpi/drivers/core/bus.c b/drivers/acpi/drivers/core/bus.c
index 6f53c46..a533245 100644
--- a/drivers/acpi/drivers/core/bus.c
+++ b/drivers/acpi/drivers/core/bus.c
@@ -53,22 +53,59 @@ static int acpi_bus_match(struct device 
 {
 	struct acpi_dev * ad = to_acpi_dev(dev);
 	struct acpi_device_driver * adrv = to_acpi_driver(drv);
-	
-	/*
-	 * First, try the HID..
-	 */
-	if (match_id(ad, adrv, acpi_dev_hid(ad)))
-		return 1;
+	int found_match = 0;
+
 
 	/*
-	 * If that doesn't work, try to match each _CID of the
-	 * device with each UID that the driver supports.
+	 * Try to match one of the driver's supported IDs with the 
+	 * HID or CID of the device. (But, only try this if the driver
+	 * supports devices with IDs (not the case w/ e.g. video devices
+	 * that don't have a HID or CID)).
 	 */
+	if (adrv->d_num_ids) {
 
-	if (match_cid(ad, adrv))
-		return 1;
+		/*
+		 * First, try the HID..
+		 */
+		found_match = match_id(ad, adrv, acpi_dev_hid(ad));
+
+		/*
+		 * ..but if that doesn't work, try to match each _CID
+		 * of the device with each UID that the driver supports.
+		 */
+		if (!found_match) 
+			found_match = match_cid(ad, adrv);
+
+		/*
+		 * If we found a matching ID, call the driver's ->d_probe() method
+		 * in the event that it needs to do a manual check to that it can
+		 * support the device.
+		 *
+		 * Every driver will have at least a dummy ->d_probe() defined
+		 * that always returns 1.
+		 */
+
+		if (found_match) {
+			int probe_good = adrv->d_probe(ad);
+
+			/*
+			 * If ->d_probe() returns 0, then revoke the 'matched'
+			 * status.
+			 *
+			 * Otherwise, we're good to go.
+			 */
+			if (!probe_good)
+				found_match = 0;
+		}
+	} else {
+		/*
+		 * If the driver doesn't have any IDs to bind to, then call the
+		 * ->d_probe() method to manually check for a supported device.
+		 */
+		found_match = adrv->d_probe(ad);
+	}
 
-	return 0;
+	return found_match;
 }
 
 
---
0.99.9.GIT