ACPI: s2idle: Log when enabling wakeup IRQ fails

enable_irq_wake() can fail. Previously acpi_s2idle_prepare() silently
ignored it's return code. Based on [1] we should try to continue even in
case of an error, so just log a warning for now.

Discovered when trying to go into s2idle under Xen. This leads to a
system that can't be woken, since xen-pirq currently doesn't support
setting wakeup IRQs [2]. With this you get at least some helpful log
message if you have access to console messages.

Link: https://lore.kernel.org/linux-acpi/20230313125344.2893-1-simon@invisiblethingslab.com/
Link: https://lore.kernel.org/linux-acpi/CAJZ5v0jahjt58nP6P5+xRdtD_ndYPvq4ecMVz6nfGu9tf5iaUw@mail.gmail.com/
Link: https://lore.kernel.org/xen-devel/20230313134102.3157-1-simon@invisiblethingslab.com/
Signed-off-by: Simon Gaiser <simon@invisiblethingslab.com>
[ rjw: Adjust white space ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/acpi/sleep.c b/drivers/acpi/sleep.c
index 4ca667251272210ab1afe05b37f7caa43eec9fbe..72470b9f16c4577fa8fe6ec5037c5e7ce0e85f75 100644 (file)
--- a/drivers/acpi/sleep.c
+++ b/drivers/acpi/sleep.c
@@ -714,7 +714,13 @@ int acpi_s2idle_begin(void)
 int acpi_s2idle_prepare(void)
 {
        if (acpi_sci_irq_valid()) {
-               enable_irq_wake(acpi_sci_irq);
+               int error;
+
+               error = enable_irq_wake(acpi_sci_irq);
+               if (error)
+                       pr_warn("Warning: Failed to enable wakeup from IRQ %d: %d\n",
+                               acpi_sci_irq, error);
+
                acpi_ec_set_gpe_wake_mask(ACPI_GPE_ENABLE);
        }