[irqchip: irq/irqchip-next] irqchip/loongson-eiointc: Fix returned value on parsing MADT

[irqchip-bot for Jianmin Lv]

The following commit has been merged into the irq/irqchip-next branch of irqchip:

Commit-ID:     112eaa8fec5ea75f1be003ec55760b09a86799f8
Gitweb:        https://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms/112eaa8fec5ea75f1be003ec55760b09a86799f8
Author:        Jianmin Lv <lvjianmin@xxxxxxxxxxx>
AuthorDate:    Fri, 07 Apr 2023 16:34:49 +08:00
Committer:     Marc Zyngier <maz@xxxxxxxxxx>
CommitterDate: Sat, 08 Apr 2023 11:29:18 +01:00

irqchip/loongson-eiointc: Fix returned value on parsing MADT

In pch_pic_parse_madt(), a NULL parent pointer will be
returned from acpi_get_vec_parent() for second pch-pic domain
related to second bridge while calling eiointc_acpi_init() at
first time, where the parent of it has not been initialized
yet, and will be initialized during second time calling
eiointc_acpi_init(). So, it's reasonable to return zero so
that failure of acpi_table_parse_madt() will be avoided, or else
acpi_cascade_irqdomain_init() will return and initialization of
followed pch_msi domain will be skipped.

Although it does not matter when pch_msi_parse_madt() returns
-EINVAL if no invalid parent is found, it's also reasonable to
return zero for that.

Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Jianmin Lv <lvjianmin@xxxxxxxxxxx>
Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20230407083453.6305-2-lvjianmin@xxxxxxxxxxx
---
 drivers/irqchip/irq-loongson-eiointc.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/irqchip/irq-loongson-eiointc.c b/drivers/irqchip/irq-loongson-eiointc.c
index d15fd38..62a632d 100644
--- a/drivers/irqchip/irq-loongson-eiointc.c
+++ b/drivers/irqchip/irq-loongson-eiointc.c
@@ -343,7 +343,7 @@ static int __init pch_pic_parse_madt(union acpi_subtable_headers *header,
 	if (parent)
 		return pch_pic_acpi_init(parent, pchpic_entry);
 
-	return -EINVAL;
+	return 0;
 }
 
 static int __init pch_msi_parse_madt(union acpi_subtable_headers *header,
@@ -355,7 +355,7 @@ static int __init pch_msi_parse_madt(union acpi_subtable_headers *header,
 	if (parent)
 		return pch_msi_acpi_init(parent, pchmsi_entry);
 
-	return -EINVAL;
+	return 0;
 }
 
 static int __init acpi_cascade_irqdomain_init(void)