From a9ddb575d6d6c58c39e8c44a22b84445fedb0521 Mon Sep 17 00:00:00 2001 From: Viresh Kumar Date: Tue, 16 Oct 2012 09:49:17 +0530 Subject: dmaengine: dw_dmac: Enhance device tree support dw_dmac driver already supports device tree but it used to have its platform data passed the non-DT way. This patch does following changes: - pass platform data via DT, non-DT way still takes precedence if both are used. - create generic filter routine - Earlier slave information was made available by slave specific filter routines in chan->private field. Now, this information would be passed from within dmac DT node. Slave drivers would now be required to pass bus_id (a string) as parameter to this generic filter(), which would be compared against the slave data passed from DT, by the generic filter routine. - Update binding document Signed-off-by: Viresh Kumar Reviewed-by: Andy Shevchenko [Fixed __devinit usage] Signed-off-by: Vinod Koul --- Documentation/devicetree/bindings/dma/snps-dma.txt | 44 ++++++++++++++++++++++ 1 file changed, 44 insertions(+) (limited to 'Documentation/devicetree/bindings/dma/snps-dma.txt') diff --git a/Documentation/devicetree/bindings/dma/snps-dma.txt b/Documentation/devicetree/bindings/dma/snps-dma.txt index c0d85dbcada5..5bb3dfb6f1d8 100644 --- a/Documentation/devicetree/bindings/dma/snps-dma.txt +++ b/Documentation/devicetree/bindings/dma/snps-dma.txt @@ -6,6 +6,26 @@ Required properties: - interrupt-parent: Should be the phandle for the interrupt controller that services interrupts for this device - interrupt: Should contain the DMAC interrupt number +- nr_channels: Number of channels supported by hardware +- is_private: The device channels should be marked as private and not for by the + general purpose DMA channel allocator. False if not passed. +- chan_allocation_order: order of allocation of channel, 0 (default): ascending, + 1: descending +- chan_priority: priority of channels. 0 (default): increase from chan 0->n, 1: + increase from chan n->0 +- block_size: Maximum block size supported by the controller +- nr_masters: Number of AHB masters supported by the controller +- data_width: Maximum data width supported by hardware per AHB master + (0 - 8bits, 1 - 16bits, ..., 5 - 256bits) +- slave_info: + - bus_id: name of this device channel, not just a device name since + devices may have more than one channel e.g. "foo_tx". For using the + dw_generic_filter(), slave drivers must pass exactly this string as + param to filter function. + - cfg_hi: Platform-specific initializer for the CFG_HI register + - cfg_lo: Platform-specific initializer for the CFG_LO register + - src_master: src master for transfers on allocated channel. + - dst_master: dest master for transfers on allocated channel. Example: @@ -14,4 +34,28 @@ Example: reg = <0xfc000000 0x1000>; interrupt-parent = <&vic1>; interrupts = <12>; + + nr_channels = <8>; + chan_allocation_order = <1>; + chan_priority = <1>; + block_size = <0xfff>; + nr_masters = <2>; + data_width = <3 3 0 0>; + + slave_info { + uart0-tx { + bus_id = "uart0-tx"; + cfg_hi = <0x4000>; /* 0x8 << 11 */ + cfg_lo = <0>; + src_master = <0>; + dst_master = <1>; + }; + spi0-tx { + bus_id = "spi0-tx"; + cfg_hi = <0x2000>; /* 0x4 << 11 */ + cfg_lo = <0>; + src_master = <0>; + dst_master = <0>; + }; + }; }; -- cgit v1.2.3-59-g8ed1b