irqchip/loongarch-cpu: Fix return value of lpic_gsi_to_irq()

lpic_gsi_to_irq() should return a valid Linux interrupt number if
acpi_register_gsi() succeeds, and return 0 otherwise. But lpic_gsi_to_irq()
converts a negative return value of acpi_register_gsi() to a positive value
silently.

Convert the return value explicitly.

Fixes: e8bba72b396c ("irqchip / ACPI: Introduce ACPI_IRQ_MODEL_LPIC for LoongArch")
Reported-by: Miao Wang <shankerwangmiao@gmail.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20240723064508.35560-1-chenhuacai@loongson.cn

diff --git a/drivers/irqchip/irq-loongarch-cpu.c b/drivers/irqchip/irq-loongarch-cpu.c
index 9d8f2c40604310d6d92fdea667c2ea0322ece015..b35903a06902f73e719626205b0ba765d2319269 100644 (file)
--- a/drivers/irqchip/irq-loongarch-cpu.c
+++ b/drivers/irqchip/irq-loongarch-cpu.c
@@ -18,11 +18,13 @@ struct fwnode_handle *cpuintc_handle;
 
 static u32 lpic_gsi_to_irq(u32 gsi)
 {
+       int irq = 0;
+
        /* Only pch irqdomain transferring is required for LoongArch. */
        if (gsi >= GSI_MIN_PCH_IRQ && gsi <= GSI_MAX_PCH_IRQ)
-               return acpi_register_gsi(NULL, gsi, ACPI_LEVEL_SENSITIVE, ACPI_ACTIVE_HIGH);
+               irq = acpi_register_gsi(NULL, gsi, ACPI_LEVEL_SENSITIVE, ACPI_ACTIVE_HIGH);
 
-       return 0;
+       return (irq > 0) ? irq : 0;
 }
 
 static struct fwnode_handle *lpic_get_gsi_domain_id(u32 gsi)