From: Angela Czubak acz@semihalf.com
[ 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 acz@semihalf.com [ rjw: Changelog rearrangement ] Signed-off-by: Rafael J. Wysocki rafael.j.wysocki@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- include/linux/ioport.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/include/linux/ioport.h b/include/linux/ioport.h index fe48b7840665..b53cb1a5b819 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; }
#ifdef CONFIG_IO_STRICT_DEVMEM