From 840872c2aed21e82579292c09ccef8f5e34b0eba Mon Sep 17 00:00:00 2001 From: Angela Czubak Date: Thu, 8 Apr 2021 12:37:59 +0200 Subject: resource: Prevent irqresource_disabled() from erasing flags [ Upstream commit d08a745729646f407277e904b02991458f20d261 ] Some Chromebooks use hard-coded interrupts in their ACPI tables. This is an excerpt as dumped on Relm: ... Name (_HID, "ELAN0001") // _HID: Hardware ID Name (_DDN, "Elan Touchscreen ") // _DDN: DOS Device Name Name (_UID, 0x05) // _UID: Unique ID Name (ISTP, Zero) Method (_CRS, 0, NotSerialized) // _CRS: Current Resource Settings { Name (BUF0, ResourceTemplate () { I2cSerialBusV2 (0x0010, ControllerInitiated, 0x00061A80, AddressingMode7Bit, "\\_SB.I2C1", 0x00, ResourceConsumer, , Exclusive, ) Interrupt (ResourceConsumer, Edge, ActiveLow, Exclusive, ,, ) { 0x000000B8, } }) Return (BUF0) /* \_SB_.I2C1.ETSA._CRS.BUF0 */ } ... This interrupt is hard-coded to 0xB8 = 184 which is too high to be mapped to IO-APIC, so no triggering information is propagated as acpi_register_gsi() fails and irqresource_disabled() is issued, which leads to erasing triggering and polarity information. Do not overwrite flags as it leads to erasing triggering and polarity information which might be useful in case of hard-coded interrupts. This way the information can be read later on even though mapping to APIC domain failed. Signed-off-by: Angela Czubak [ rjw: Changelog rearrangement ] Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin --- include/linux/ioport.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/ioport.h b/include/linux/ioport.h index 55de385c839c..647744d8514e 100644 --- a/include/linux/ioport.h +++ b/include/linux/ioport.h @@ -331,7 +331,7 @@ static inline void irqresource_disabled(struct resource *res, u32 irq) { res->start = irq; res->end = irq; - res->flags = IORESOURCE_IRQ | IORESOURCE_DISABLED | IORESOURCE_UNSET; + res->flags |= IORESOURCE_IRQ | IORESOURCE_DISABLED | IORESOURCE_UNSET; } extern struct address_space *iomem_get_mapping(void); -- cgit v1.2.3