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Diffstat (limited to 'Documentation/firmware-guide')
| -rw-r--r-- | Documentation/firmware-guide/acpi/enumeration.rst | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/Documentation/firmware-guide/acpi/enumeration.rst b/Documentation/firmware-guide/acpi/enumeration.rst index c414646a1bb4..47fb4d6d4557 100644 --- a/Documentation/firmware-guide/acpi/enumeration.rst +++ b/Documentation/firmware-guide/acpi/enumeration.rst @@ -142,6 +142,45 @@ In robust cases the client unfortunately needs to call acpi_dma_request_slave_chan_by_index() directly and therefore choose the specific FixedDMA resource by its index. +Named Interrupts +================ + +Drivers enumerated via ACPI can have names to interrupts in the ACPI table +which can be used to get the IRQ number in the driver. + +The interrupt name can be listed in _DSD as 'interrupt-names'. The names +should be listed as an array of strings which will map to the Interrupt() +resource in the ACPI table corresponding to its index. + +The table below shows an example of its usage:: + + Device (DEV0) { + ... + Name (_CRS, ResourceTemplate() { + ... + Interrupt (ResourceConsumer, Level, ActiveHigh, Exclusive) { + 0x20, + 0x24 + } + }) + + Name (_DSD, Package () { + ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), + Package () { + Package () {"interrupt-names", + Package (2) {"default", "alert"}}, + } + ... + }) + } + +The interrupt name 'default' will correspond to 0x20 in Interrupt() +resource and 'alert' to 0x24. Note that only the Interrupt() resource +is mapped and not GpioInt() or similar. + +The driver can call the function - fwnode_irq_get_byname() with the fwnode +and interrupt name as arguments to get the corresponding IRQ number. + SPI serial bus support ====================== |