Commits
Mika Westerberg committed 3f4232ee8b5
acpi-dma: Add support for "dma-names" device property
The current implementation hard codes the two supported channels so that
"tx" is always 0 and "rx" is always 1. This is because there has been no
suitable way in ACPI to name resources.
With _DSD device properties we can finally do this:
Device (SPI1) {
Name (_CRS, ResourceTemplate () {
...
FixedDMA (0x0000, 0x0000, Width32bit)
FixedDMA (0x0001, 0x0001, Width32bit)
})
Name (_DSD, Package () {
ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
Package () {
Package () {"dma-names", Package () {"tx", "rx"}}
},
})
}
The names "tx" and "rx" now provide index of the FixedDMA resource in
question.
Modify acpi_dma_request_slave_chan_by_name() so that it looks for
"dma-names" property first and only then fall back using hardcoded indices.
The DT "dma-names" binding that we reuse for ACPI is documented in
Documentation/devicetree/bindings/dma/dma.txt.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>