[v3] ACPI: resources: add legacy irq override exception by DMI info

After the commit 0ec4e55e9f57 ("ACPI: resources: Add checks for ACPI
IRQ override") is reverted, the keyboard of those Medion laptops can't
work again.

To fix the keyboard issue, here adding an override check by DMI info,
this will not affect other machines and this design refers to
the prt_quirks[] in the drivers/acpi/pci_irq.c.

If we meet similar issues on other platforms, we could expand the
table of skip_override_table[] or medion_laptop[].

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>
---
 drivers/acpi/resource.c | 49 +++++++++++++++++++++++++++++++++++++++--
 1 file changed, 47 insertions(+), 2 deletions(-)

On Wed, Sep 15, 2021 at 3:09 PM Hui Wang <hui.wang@canonical.com> wrote:
>
> After the commit 0ec4e55e9f57 ("ACPI: resources: Add checks for ACPI
> IRQ override") is reverted, the keyboard of those Medion laptops can't
> work again.
>
> To fix the keyboard issue, here adding an override check by DMI info,
> this will not affect other machines and this design refers to
> the prt_quirks[] in the drivers/acpi/pci_irq.c.
>
> If we meet similar issues on other platforms, we could expand the
> table of skip_override_table[] or medion_laptop[].
>
> 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>
> ---
>  drivers/acpi/resource.c | 49 +++++++++++++++++++++++++++++++++++++++--
>  1 file changed, 47 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/acpi/resource.c b/drivers/acpi/resource.c
> index ee78a210c606..7bf38652e6ac 100644
> --- a/drivers/acpi/resource.c
> +++ b/drivers/acpi/resource.c
> @@ -16,6 +16,7 @@
>  #include <linux/ioport.h>
>  #include <linux/slab.h>
>  #include <linux/irq.h>
> +#include <linux/dmi.h>
>
>  #ifdef CONFIG_X86
>  #define valid_IRQ(i) (((i) != 0) && ((i) != 2))
> @@ -380,9 +381,51 @@ unsigned int acpi_dev_get_irq_type(int triggering, int polarity)
>  }
>  EXPORT_SYMBOL_GPL(acpi_dev_get_irq_type);
>
> +static const struct dmi_system_id medion_laptop[] = {
> +       {
> +               .ident = "MEDION P15651",
> +               .matches = {
> +                       DMI_MATCH(DMI_SYS_VENDOR, "MEDION"),
> +                       DMI_MATCH(DMI_BOARD_NAME, "M15T"),
> +               },
> +       },
> +       { }
> +};
> +
> +struct irq_override_cmp {
> +       const struct dmi_system_id *system;
> +       unsigned char irq;
> +       unsigned char triggering;
> +       unsigned char polarity;
> +       unsigned char shareable;
> +};
> +
> +static const struct irq_override_cmp skip_override_table[] = {
> +       { medion_laptop, 1, ACPI_LEVEL_SENSITIVE, ACPI_ACTIVE_LOW, 0 },
> +};
> +
> +static bool acpi_dev_irq_override(u32 gsi, u8 triggering, u8 polarity,
> +                                 u8 shareable)
> +{
> +       int i;
> +
> +       for (i = 0; i < ARRAY_SIZE(skip_override_table); i++) {
> +               const struct irq_override_cmp *entry = &skip_override_table[i];
> +
> +               if (dmi_check_system(entry->system) &&
> +                   entry->irq == gsi &&
> +                   entry->triggering == triggering &&
> +                   entry->polarity == polarity &&
> +                   entry->shareable == shareable)
> +                       return false;
> +       }
> +
> +       return true;
> +}
> +
>  static void acpi_dev_get_irqresource(struct resource *res, u32 gsi,
>                                      u8 triggering, u8 polarity, u8 shareable,
> -                                    bool legacy)
> +                                    bool check_override)
>  {
>         int irq, p, t;
>
> @@ -401,7 +444,9 @@ static void acpi_dev_get_irqresource(struct resource *res, u32 gsi,
>          * using extended IRQ descriptors we take the IRQ configuration
>          * from _CRS directly.
>          */
> -       if (legacy && !acpi_get_override_irq(gsi, &t, &p)) {
> +       if (check_override &&
> +           acpi_dev_irq_override(gsi, triggering, polarity, shareable) &&
> +           !acpi_get_override_irq(gsi, &t, &p)) {
>                 u8 trig = t ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE;
>                 u8 pol = p ? ACPI_ACTIVE_LOW : ACPI_ACTIVE_HIGH;
>
> --

Applied as 5.16 material under the subject "ACPI: resources: Add
DMI-based legacy IRQ override quirk" with some changelog edits.

Thanks!