Fix very high interrupt rate for IRQ8 (rtc) unless pnpacpi=off
Workaround for broken systems with BIOS that makes RTC interrupt level
triggered and/or active low.
See http://bugzilla.kernel.org/show_bug.cgi?id=5243
Based on the patch from Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Krzysztof Piotr Oledzki <ole@ans.pl>
Cc: "Li, Shaohua" <shaohua.li@intel.com>
Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Adam Belay <ambx1@neo.rr.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/pnp/pnpacpi/rsparser.c b/drivers/pnp/pnpacpi/rsparser.c
index 0e3b8d0..cd0a204 100644
--- a/drivers/pnp/pnpacpi/rsparser.c
+++ b/drivers/pnp/pnpacpi/rsparser.c
@@ -85,6 +85,16 @@
if (i >= PNP_MAX_IRQ)
return;
+#ifdef CONFIG_X86
+ if (gsi < 16 && (triggering != ACPI_EDGE_SENSITIVE ||
+ polarity != ACPI_ACTIVE_HIGH)) {
+ pnp_warn("BIOS BUG: legacy PNP IRQ %d should be edge trigger, "
+ "active high", gsi);
+ triggering = ACPI_EDGE_SENSITIVE;
+ polarity = ACPI_ACTIVE_HIGH;
+ }
+#endif
+
res->irq_resource[i].flags = IORESOURCE_IRQ; // Also clears _UNSET flag
res->irq_resource[i].flags |= irq_flags(triggering, polarity);
irq = acpi_register_gsi(gsi, triggering, polarity);
