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| author | Akhil R <akhilrajeev@nvidia.com> | 2022-01-28 17:14:26 +0530 |
|---|---|---|
| committer | Wolfram Sang <wsa@kernel.org> | 2022-01-28 21:56:09 +0100 |
| commit | 20e8ef5c7ffaa4c1d5f65727c536ffaf37078d5f (patch) | |
| tree | 9d97e4fef78351d2e8118045e97329b4e5088f46 | |
| parent | ca0acb511c21738b32386ce0f85c284b351d919e (diff) | |
docs: firmware-guide: ACPI: Add named interrupt doc
Add a detailed example of the named interrupts in the ACPI table.
Signed-off-by: Akhil R <akhilrajeev@nvidia.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
| -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 74b830b2fd59..d0022567c022 100644 --- a/Documentation/firmware-guide/acpi/enumeration.rst +++ b/Documentation/firmware-guide/acpi/enumeration.rst @@ -143,6 +143,45 @@ 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 ====================== |