commit e9fe9e188118a0a34c6200d9b10ea6247f53592d
author Bjorn Helgaas <bjorn.helgaas@hp.com> Mon Jun 09 16:52:04 2008 -0700
committer Len Brown <len.brown@intel.com> Wed Jun 11 19:13:46 2008 -0400
tree 151fb9549cefbcf7a8f7e1d591c99381d2c9802c
parent 0638bc8dc037d844efe1d4abf44488c037705905

pnpacpi: fix IRQ flag decoding

When decoding IRQ trigger mode and polarity, it is not enough to mask by
IORESOURCE_BITS because there are now additional bits defined.  For
example, if IORESOURCE_IRQ_SHAREABLE was set, we failed to set *triggering
and *polarity at all.

I can't point to a failure that this patch fixes, but
bugs in this area have caused problems when resuming after
suspend, for example:

    http://bugzilla.kernel.org/show_bug.cgi?id=6316
    http://bugzilla.kernel.org/show_bug.cgi?id=9487
    https://bugs.launchpad.net/ubuntu/+source/linux-source-2.6.22/+bug/152187

This is based on a patch by Tom Jaeger:
    http://bugzilla.kernel.org/show_bug.cgi?id=9487#c32

[rene.herman@keyaccess.nl: fix comment]
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>

drivers/pnp/pnpacpi/rsparser.c

diff --git a/drivers/pnp/pnpacpi/rsparser.c b/drivers/pnp/pnpacpi/rsparser.c
index 0201c8a..ab09fe6 100644
--- a/drivers/pnp/pnpacpi/rsparser.c
+++ b/drivers/pnp/pnpacpi/rsparser.c
@@ -56,9 +56,11 @@
 	return flags;
 }
 
-static void decode_irq_flags(int flag, int *triggering, int *polarity)
+static void decode_irq_flags(struct pnp_dev *dev, int flags, int *triggering,
+			     int *polarity)
 {
-	switch (flag) {
+	switch (flags & (IORESOURCE_IRQ_LOWLEVEL | IORESOURCE_IRQ_HIGHLEVEL |
+			 IORESOURCE_IRQ_LOWEDGE  | IORESOURCE_IRQ_HIGHEDGE)) {
 	case IORESOURCE_IRQ_LOWLEVEL:
 		*triggering = ACPI_LEVEL_SENSITIVE;
 		*polarity = ACPI_ACTIVE_LOW;
@@ -75,6 +77,12 @@
 		*triggering = ACPI_EDGE_SENSITIVE;
 		*polarity = ACPI_ACTIVE_HIGH;
 		break;
+	default:
+		dev_err(&dev->dev, "can't encode invalid IRQ mode %#x\n",
+			flags);
+		*triggering = ACPI_EDGE_SENSITIVE;
+		*polarity = ACPI_ACTIVE_HIGH;
+		break;
 	}
 }
 
@@ -790,7 +798,7 @@
 	struct acpi_resource_irq *irq = &resource->data.irq;
 	int triggering, polarity;
 
-	decode_irq_flags(p->flags & IORESOURCE_BITS, &triggering, &polarity);
+	decode_irq_flags(dev, p->flags, &triggering, &polarity);
 	irq->triggering = triggering;
 	irq->polarity = polarity;
 	if (triggering == ACPI_EDGE_SENSITIVE)
@@ -813,7 +821,7 @@
 	struct acpi_resource_extended_irq *extended_irq = &resource->data.extended_irq;
 	int triggering, polarity;
 
-	decode_irq_flags(p->flags & IORESOURCE_BITS, &triggering, &polarity);
+	decode_irq_flags(dev, p->flags, &triggering, &polarity);
 	extended_irq->producer_consumer = ACPI_CONSUMER;
 	extended_irq->triggering = triggering;
 	extended_irq->polarity = polarity;