[PATCH v3] ACPI : don't always override the acpi irq

[PATCH v3] ACPI : don't always override the acpi irq

[Hui Wang]

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 let the linux kernel skip the irq
override, the keyboard will work normally.

From the existing comment in the acpi_dev_get_irqresource(), the
override function only needs to be called when BIOS defines IRQ() or
IRQNoFlags, and according to the Section 6.4.2.1 of ACPI 6.4 spec [1],
if IRQ() is empty or defines IRQNoFlags, the IRQ is High true, edge
sensitive and non-shareable. The linux ACPI driver (acpi_rs_set_irq[]
in rsirq.c) also assumes so.

Here check 3 conditions to decide if the legacy is true or not, if it
is true, it means the IRQ() is empty or defines IRQNoFlags and need to
call irq_override().

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-and-tested-by: Manuel Krause <manuelkrause@netscape.net>
Signed-off-by: Hui Wang <hui.wang@canonical.com>
---
 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 ee78a210c606..dc01fb550b28 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;
-- 
2.25.1

Re: [PATCH v3] ACPI : don't always override the acpi irq

[Rafael J. Wysocki]

On Wed, Jun 9, 2021 at 4:14 AM Hui Wang <hui.wang@canonical.com> wrote:
>
> 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 let the linux kernel skip the irq
> override, the keyboard will work normally.
>
> From the existing comment in the acpi_dev_get_irqresource(), the
> override function only needs to be called when BIOS defines IRQ() or
> IRQNoFlags, and according to the Section 6.4.2.1 of ACPI 6.4 spec [1],
> if IRQ() is empty or defines IRQNoFlags, the IRQ is High true, edge
> sensitive and non-shareable. The linux ACPI driver (acpi_rs_set_irq[]
> in rsirq.c) also assumes so.
>
> Here check 3 conditions to decide if the legacy is true or not, if it
> is true, it means the IRQ() is empty or defines IRQNoFlags and need to
> call irq_override().
>
> 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-and-tested-by: Manuel Krause <manuelkrause@netscape.net>
> Signed-off-by: Hui Wang <hui.wang@canonical.com>
> ---
>  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 ee78a210c606..dc01fb550b28 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;
> --

Applied as 5.14 material under a new subject ("ACPI: resources: Add
checks for ACPI IRQ override") and with some edits in the patch
changelog.

Note, however, that this is a change in behavior that may result in
regressions on old machines, in which case some further refinements of
the code will be necessary.

Thanks!

Re: [PATCH v3] ACPI : don't always override the acpi irq

[Manuel Krause]

On 09/06/2021 14:44, Rafael J. Wysocki wrote:
> On Wed, Jun 9, 2021 at 4:14 AM Hui Wang <hui.wang@canonical.com> wrote:
>>
>> 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 let the linux kernel skip the irq
>> override, the keyboard will work normally.
>>
>>  From the existing comment in the acpi_dev_get_irqresource(), the
>> override function only needs to be called when BIOS defines IRQ() or
>> IRQNoFlags, and according to the Section 6.4.2.1 of ACPI 6.4 spec [1],
>> if IRQ() is empty or defines IRQNoFlags, the IRQ is High true, edge
>> sensitive and non-shareable. The linux ACPI driver (acpi_rs_set_irq[]
>> in rsirq.c) also assumes so.
>>
>> Here check 3 conditions to decide if the legacy is true or not, if it
>> is true, it means the IRQ() is empty or defines IRQNoFlags and need to
>> call irq_override().
>>
>> 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-and-tested-by: Manuel Krause <manuelkrause@netscape.net>
>> Signed-off-by: Hui Wang <hui.wang@canonical.com>
>> ---
>>   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 ee78a210c606..dc01fb550b28 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;
>> --
> 
> Applied as 5.14 material under a new subject ("ACPI: resources: Add
> checks for ACPI IRQ override") and with some edits in the patch
> changelog.
> 
> Note, however, that this is a change in behavior that may result in
> regressions on old machines, in which case some further refinements of
> the code will be necessary.
> 
> Thanks!
> 

I just want to assure you, that also [PATCH v3] works fine on here.
Maybe I can find some time to re-activate my other, over 12 years 
old, HP notebook and check for possible issues with this patch.

I have to thank you all for your great work!

Best regards,
Manuel

Re: [PATCH v3] ACPI : don't always override the acpi irq

[Hui Wang]

On 6/9/21 8:44 PM, Rafael J. Wysocki wrote:
> On Wed, Jun 9, 2021 at 4:14 AM Hui Wang <hui.wang@canonical.com> wrote:
>> The laptop keyboard doesn't work on many MEDION notebooks, but the
>>
>> +                                        irq->shareable, irq_is_legacy(irq));
>>                  break;
>>          case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
>>                  ext_irq = &ares->data.extended_irq;
>> --
> Applied as 5.14 material under a new subject ("ACPI: resources: Add
> checks for ACPI IRQ override") and with some edits in the patch
> changelog.
>
> Note, however, that this is a change in behavior that may result in
> regressions on old machines, in which case some further refinements of
> the code will be necessary.
>
> Thanks!
Understand. Thanks.