From e9f850ba66cdf6b77fb4f005e46c4b605c4de434 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 4 Mar 2026 13:55:43 +0100 Subject: [PATCH] rtc: cmos: Use platform_get_irq_optional() in cmos_platform_probe() The rtc-cmos driver can live without an IRQ and returning an error code from platform_get_irq() is not a problem for it in general, so make it call platform_get_irq_optional() in cmos_platform_probe() instead of platform_get_irq() to avoid a confusing error message printed by the latter if an IRQ cannot be found for index 0, which is possible on x86 platforms. Additionally, on x86, if the IRQ is not defined and the system has a legacy PIC, hardcode it to RTC_IRQ, which should be safe then (and which is what the dropped PNP code did). Fixes: d15f1c2e413e ("ACPI: PNP: Drop CMOS RTC PNP device support") Reported-by: Nathan Chancellor Closes: https://lore.kernel.org/linux-acpi/20260303060752.GA2749263@ax162/ Tested-by: Nathan Chancellor Signed-off-by: Rafael J. Wysocki Link: https://patch.msgid.link/12857714.O9o76ZdvQC@rafael.j.wysocki Signed-off-by: Alexandre Belloni --- drivers/rtc/rtc-cmos.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/drivers/rtc/rtc-cmos.c b/drivers/rtc/rtc-cmos.c index 0743c6acd6e2..9cc1c3b53c4b 100644 --- a/drivers/rtc/rtc-cmos.c +++ b/drivers/rtc/rtc-cmos.c @@ -1493,9 +1493,18 @@ static int __init cmos_platform_probe(struct platform_device *pdev) resource = platform_get_resource(pdev, IORESOURCE_IO, 0); else resource = platform_get_resource(pdev, IORESOURCE_MEM, 0); - irq = platform_get_irq(pdev, 0); - if (irq < 0) + irq = platform_get_irq_optional(pdev, 0); + if (irq < 0) { irq = -1; +#ifdef CONFIG_X86 + /* + * On some x86 systems, the IRQ is not defined, but it should + * always be safe to hardcode it on systems with a legacy PIC. + */ + if (nr_legacy_irqs()) + irq = RTC_IRQ; +#endif + } return cmos_do_probe(&pdev->dev, resource, irq); }