lkml.org 
[lkml]   [2021]   [Jul]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 5.10 187/593] ACPI: resources: Add checks for ACPI IRQ override
    Date
    From: Hui Wang <hui.wang@canonical.com>

    [ Upstream commit 0ec4e55e9f571f08970ed115ec0addc691eda613 ]

    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 <rafael.j.wysocki@intel.com>
    Reported-by: Manuel Krause <manuelkrause@netscape.net>
    Tested-by: Manuel Krause <manuelkrause@netscape.net>
    Signed-off-by: Hui Wang <hui.wang@canonical.com>
    [ rjw: Subject rewrite, changelog edits ]
    Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
    Signed-off-by: Sasha Levin <sashal@kernel.org>
    ---
    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 f2f5f1dc7c61..9d82440a1d75 100644
    --- a/drivers/acpi/resource.c
    +++ b/drivers/acpi/resource.c
    @@ -430,6 +430,13 @@ 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.
    @@ -468,7 +475,7 @@ 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;
    --
    2.30.2


    \
     
     \ /
      Last update: 2021-07-12 09:09    [W:2.606 / U:0.464 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site