From 0ec4e55e9f571f08970ed115ec0addc691eda613 Mon Sep 17 00:00:00 2001 From: Hui Wang Date: Wed, 9 Jun 2021 10:14:42 +0800 Subject: [PATCH] ACPI: resources: Add checks for ACPI IRQ override The laptop keyboard doesn't work on many MEDION notebooks, but the keyboard works well under Windows and Unix. Through debugging, we found this log in the dmesg: ACPI: IRQ 1 override to edge, high pnp 00:03: Plug and Play ACPI device, IDs PNP0303 (active) And we checked the IRQ definition in the DSDT, it is: IRQ (Level, ActiveLow, Exclusive, ) {1} So the BIOS defines the keyboard IRQ to Level_Low, but the Linux kernel override it to Edge_High. If the Linux kernel is modified to skip the IRQ override, the keyboard will work normally. From the existing comment in acpi_dev_get_irqresource(), the override function only needs to be called when IRQ() or IRQNoFlags() is used to populate the resource descriptor, and according to Section 6.4.2.1 of ACPI 6.4 [1], if IRQ() is empty or IRQNoFlags() is used, the IRQ is High true, edge sensitive and non-shareable. ACPICA also assumes that to be the case (see acpi_rs_set_irq[] in rsirq.c). In accordance with the above, check 3 additional conditions (EdgeSensitive, ActiveHigh and Exclusive) when deciding whether or not to treat an ACPI_RESOURCE_TYPE_IRQ resource as "legacy", in which case the IRQ override is applicable to it. Link: https://uefi.org/specs/ACPI/6.4/06_Device_Configuration/Device_Configuration.html#irq-descriptor # [1] BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=213031 BugLink: http://bugs.launchpad.net/bugs/1909814 Suggested-by: Rafael J. Wysocki Reported-by: Manuel Krause Tested-by: Manuel Krause Signed-off-by: Hui Wang [ rjw: Subject rewrite, changelog edits ] Signed-off-by: Rafael J. Wysocki --- drivers/acpi/resource.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/drivers/acpi/resource.c b/drivers/acpi/resource.c index ee78a210c..dc01fb5 100644 --- a/drivers/acpi/resource.c +++ b/drivers/acpi/resource.c @@ -423,6 +423,13 @@ static void acpi_dev_get_irqresource(struct resource *res, u32 gsi, } } +static bool irq_is_legacy(struct acpi_resource_irq *irq) +{ + return irq->triggering == ACPI_EDGE_SENSITIVE && + irq->polarity == ACPI_ACTIVE_HIGH && + irq->shareable == ACPI_EXCLUSIVE; +} + /** * acpi_dev_resource_interrupt - Extract ACPI interrupt resource information. * @ares: Input ACPI resource object. @@ -461,7 +468,7 @@ bool acpi_dev_resource_interrupt(struct acpi_resource *ares, int index, } acpi_dev_get_irqresource(res, irq->interrupts[index], irq->triggering, irq->polarity, - irq->shareable, true); + irq->shareable, irq_is_legacy(irq)); break; case ACPI_RESOURCE_TYPE_EXTENDED_IRQ: ext_irq = &ares->data.extended_irq; -- 2.7.4