Commit dfcfe386 authored by Stefan Wahren's avatar Stefan Wahren Committed by Vinod Koul
Browse files

dt-bindings: dma: convert bcm2835-dma bindings to YAML



Convert the DT binding document for bcm2835-dma from .txt to YAML.

Signed-off-by: default avatarStefan Wahren <stefan.wahren@i2se.com>
Reviewed-by: default avatarRob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20230617133620.53129-3-stefan.wahren@i2se.com


Signed-off-by: default avatarVinod Koul <vkoul@kernel.org>
parent fbac8ceb
Loading
Loading
Loading
Loading
+0 −83
Original line number Diff line number Diff line
* BCM2835 DMA controller

The BCM2835 DMA controller has 16 channels in total.
Only the lower 13 channels have an associated IRQ.
Some arbitrary channels are used by the firmware
(1,3,6,7 in the current firmware version).
The channels 0,2 and 3 have special functionality
and should not be used by the driver.

Required properties:
- compatible: Should be "brcm,bcm2835-dma".
- reg: Should contain DMA registers location and length.
- interrupts: Should contain the DMA interrupts associated
		to the DMA channels in ascending order.
- interrupt-names: Should contain the names of the interrupt
		   in the form "dmaXX".
		   Use "dma-shared-all" for the common interrupt line
		   that is shared by all dma channels.
- #dma-cells: Must be <1>, the cell in the dmas property of the
		client device represents the DREQ number.
- brcm,dma-channel-mask: Bit mask representing the channels
			 not used by the firmware in ascending order,
			 i.e. first channel corresponds to LSB.

Example:

dma: dma@7e007000 {
	compatible = "brcm,bcm2835-dma";
	reg = <0x7e007000 0xf00>;
	interrupts = <1 16>,
		     <1 17>,
		     <1 18>,
		     <1 19>,
		     <1 20>,
		     <1 21>,
		     <1 22>,
		     <1 23>,
		     <1 24>,
		     <1 25>,
		     <1 26>,
		     /* dma channel 11-14 share one irq */
		     <1 27>,
		     <1 27>,
		     <1 27>,
		     <1 27>,
		     /* unused shared irq for all channels */
		     <1 28>;
	interrupt-names = "dma0",
			  "dma1",
			  "dma2",
			  "dma3",
			  "dma4",
			  "dma5",
			  "dma6",
			  "dma7",
			  "dma8",
			  "dma9",
			  "dma10",
			  "dma11",
			  "dma12",
			  "dma13",
			  "dma14",
			  "dma-shared-all";

	#dma-cells = <1>;
	brcm,dma-channel-mask = <0x7f35>;
};


DMA clients connected to the BCM2835 DMA controller must use the format
described in the dma.txt file, using a two-cell specifier for each channel.

Example:

bcm2835_i2s: i2s@7e203000 {
	compatible = "brcm,bcm2835-i2s";
	reg = <	0x7e203000 0x24>;
	clocks = <&clocks BCM2835_CLOCK_PCM>;

	dmas = <&dma 2>,
	       <&dma 3>;
	dma-names = "tx", "rx";
};
+102 −0
Original line number Diff line number Diff line
# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
%YAML 1.2
---
$id: http://devicetree.org/schemas/dma/brcm,bcm2835-dma.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#

title: BCM2835 DMA controller

maintainers:
  - Nicolas Saenz Julienne <nsaenz@kernel.org>

description:
  The BCM2835 DMA controller has 16 channels in total. Only the lower
  13 channels have an associated IRQ. Some arbitrary channels are used by the
  VideoCore firmware (1,3,6,7 in the current firmware version). The channels
  0, 2 and 3 have special functionality and should not be used by the driver.

allOf:
  - $ref: dma-controller.yaml#

properties:
  compatible:
    const: brcm,bcm2835-dma

  reg:
    maxItems: 1

  interrupts:
    description:
      Should contain the DMA interrupts associated to the DMA channels in
      ascending order.
    minItems: 1
    maxItems: 16

  interrupt-names:
    minItems: 1
    maxItems: 16

  '#dma-cells':
    description: The single cell represents the DREQ number.
    const: 1

  brcm,dma-channel-mask:
    $ref: /schemas/types.yaml#/definitions/uint32
    description:
      Bitmask of available DMA channels in ascending order that are
      not reserved by firmware and are available to the
      kernel. i.e. first channel corresponds to LSB.

unevaluatedProperties: false

required:
  - compatible
  - reg
  - interrupts
  - "#dma-cells"
  - brcm,dma-channel-mask

examples:
  - |
    dma-controller@7e007000 {
      compatible = "brcm,bcm2835-dma";
      reg = <0x7e007000 0xf00>;
      interrupts = <1 16>,
                   <1 17>,
                   <1 18>,
                   <1 19>,
                   <1 20>,
                   <1 21>,
                   <1 22>,
                   <1 23>,
                   <1 24>,
                   <1 25>,
                   <1 26>,
                   /* dma channel 11-14 share one irq */
                   <1 27>,
                   <1 27>,
                   <1 27>,
                   <1 27>,
                   /* unused shared irq for all channels */
                   <1 28>;
      interrupt-names = "dma0",
                        "dma1",
                        "dma2",
                        "dma3",
                        "dma4",
                        "dma5",
                        "dma6",
                        "dma7",
                        "dma8",
                        "dma9",
                        "dma10",
                        "dma11",
                        "dma12",
                        "dma13",
                        "dma14",
                        "dma-shared-all";
        #dma-cells = <1>;
        brcm,dma-channel-mask = <0x7f35>;
    };

...