[PATCH v1 1/2] ACPI/PCI: Make _SRS optional for link device

From: Pierre Gondois
Date: Fri Jul 01 2022 - 12:03:49 EST


From: Pierre Gondois <Pierre.Gondois@xxxxxxx>

In ACPI 6.4, s6.2.13 "_PRT (PCI Routing Table)", PCI legacy
interrupts can be described though a link device (first model).
>From s6.2.16 "_SRS (Set Resource Settings)":
"This optional control method [...]"

Make it optional to have a _SRS method for link devices.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=215560
Signed-off-by: Pierre Gondois <pierre.gondois@xxxxxxx>
---
drivers/acpi/pci_link.c | 7 +++++++
1 file changed, 7 insertions(+)

diff --git a/drivers/acpi/pci_link.c b/drivers/acpi/pci_link.c
index 58647051c948..129e3e7e80ee 100644
--- a/drivers/acpi/pci_link.c
+++ b/drivers/acpi/pci_link.c
@@ -288,6 +288,13 @@ static int acpi_pci_link_set(struct acpi_pci_link *link, int irq)
if (!irq)
return -EINVAL;

+ if (!acpi_has_method(handle, METHOD_NAME__SRS)) {
+ if (link->irq.active == irq)
+ return 0;
+ acpi_handle_err(handle, "Unable to set IRQ %d: No _SRS.\n", irq);
+ return -ENODEV;
+ }
+
resource = kzalloc(sizeof(*resource) + 1, irqs_disabled() ? GFP_ATOMIC: GFP_KERNEL);
if (!resource)
return -ENOMEM;
--
2.25.1