# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
%YAML 1.2
---
$id: http://devicetree.org/schemas/sound/fsl,ssi.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#
title: Freescale Synchronous Serial Interface
maintainers:
- Shengjiu Wang <[email protected]>
description:
Notes on fsl,playback-dma and fsl,capture-dma
On SOCs that have an SSI, specific DMA channels are hard-wired for playback
and capture. On the MPC8610, for example, SSI1 must use DMA channel 0 for
playback and DMA channel 1 for capture. SSI2 must use DMA channel 2 for
playback and DMA channel 3 for capture. The developer can choose which
DMA controller to use, but the channels themselves are hard-wired. The
purpose of these two properties is to represent this hardware design.
The device tree nodes for the DMA channels that are referenced by
"fsl,playback-dma" and "fsl,capture-dma" must be marked as compatible with
"fsl,ssi-dma-channel". The SOC-specific compatible string (e.g.
"fsl,mpc8610-dma-channel") can remain. If these nodes are left as
"fsl,elo-dma-channel" or "fsl,eloplus-dma-channel", then the generic Elo DMA
drivers (fsldma) will attempt to use them, and it will conflict with the
sound drivers.
properties:
compatible:
oneOf:
- items:
- enum:
- fsl,imx50-ssi
- fsl,imx53-ssi
- const: fsl,imx51-ssi
- const: fsl,imx21-ssi
- items:
- enum:
- fsl,imx25-ssi
- fsl,imx27-ssi
- fsl,imx35-ssi
- fsl,imx51-ssi
- const: fsl,imx21-ssi
- items:
- enum:
- fsl,imx6q-ssi
- fsl,imx6sl-ssi
- fsl,imx6sx-ssi
- const: fsl,imx51-ssi
- items:
- const: fsl,imx21-ssi
- items:
- const: fsl,mpc8610-ssi
reg:
maxItems: 1
interrupts:
maxItems: 1
clocks:
items:
- description: The ipg clock for register access
- description: clock for SSI master mode
minItems: 1
clock-names:
items:
- const: ipg
- const: baud
minItems: 1
dmas:
oneOf:
- items:
- description: DMA controller phandle and request line for RX
- description: DMA controller phandle and request line for TX
- items:
- description: DMA controller phandle and request line for RX0
- description: DMA controller phandle and request line for TX0
- description: DMA controller phandle and request line for RX1
- description: DMA controller phandle and request line for TX1
dma-names:
oneOf:
- items:
- const: rx
- const: tx
- items:
- const: rx0
- const: tx0
- const: rx1
- const: tx1
"#sound-dai-cells":
const: 0
description: optional, some dts node didn't add it.
cell-index:
$ref: /schemas/types.yaml#/definitions/uint32
enum: [0, 1, 2]
description: The SSI index
ac97-gpios:
$ref: /schemas/types.yaml#/definitions/phandle-array
description: Please refer to soc-ac97link.txt
codec-handle:
$ref: /schemas/types.yaml#/definitions/phandle
description:
Phandle to a 'codec' node that defines an audio
codec connected to this SSI. This node is typically
a child of an I2C or other control node.
fsl,fifo-depth:
$ref: /schemas/types.yaml#/definitions/uint32
description:
The number of elements in the transmit and receive FIFOs.
This number is the maximum allowed value for SFCSR[TFWM0].
enum: [8, 15]
fsl,fiq-stream-filter:
type: boolean
description:
Disabled DMA and use FIQ instead to filter the codec stream.
This is necessary for some boards where an incompatible codec
is connected to this SSI, e.g. on pca100 and pcm043.
fsl,mode:
$ref: /schemas/types.yaml#/definitions/string
enum: [ ac97-slave, ac97-master, i2s-slave, i2s-master,
lj-slave, lj-master, rj-slave, rj-master ]
description: |
"ac97-slave" - AC97 mode, SSI is clock slave
"ac97-master" - AC97 mode, SSI is clock master
"i2s-slave" - I2S mode, SSI is clock slave
"i2s-master" - I2S mode, SSI is clock master
"lj-slave" - Left justified mode, SSI is clock slave
"lj-master" - Left justified mode, SSI is clock master
"rj-slave" - Right justified mode, SSI is clock slave
"rj-master" - Right justified mode, SSI is clock master
fsl,ssi-asynchronous:
type: boolean
description: If specified, the SSI is to be programmed in asynchronous
mode. In this mode, pins SRCK, STCK, SRFS, and STFS must
all be connected to valid signals. In synchronous mode,
SRCK and SRFS are ignored. Asynchronous mode allows
playback and capture to use different sample sizes and
sample rates. Some drivers may require that SRCK and STCK
be connected together, and SRFS and STFS be connected
together. This would still allow different sample sizes,
but not different sample rates.
fsl,playback-dma:
$ref: /schemas/types.yaml#/definitions/phandle
description: Phandle to a node for the DMA channel to use for
playback of audio. This is typically dictated by SOC
design. Only used on Power Architecture.
fsl,capture-dma:
$ref: /schemas/types.yaml#/definitions/phandle
description: Phandle to a node for the DMA channel to use for
capture (recording) of audio. This is typically dictated
by SOC design. Only used on Power Architecture.
required:
- compatible
- reg
- interrupts
- fsl,fifo-depth
allOf:
- $ref: dai-common.yaml#
unevaluatedProperties: false
examples:
- |
#include <dt-bindings/interrupt-controller/arm-gic.h>
#include <dt-bindings/clock/imx6qdl-clock.h>
ssi@2028000 {
compatible = "fsl,imx6q-ssi", "fsl,imx51-ssi";
reg = <0x02028000 0x4000>;
interrupts = <GIC_SPI 46 IRQ_TYPE_LEVEL_HIGH>;
clocks = <&clks IMX6QDL_CLK_SSI1_IPG>,
<&clks IMX6QDL_CLK_SSI1>;
clock-names = "ipg", "baud";
dmas = <&sdma 37 1 0>, <&sdma 38 1 0>;
dma-names = "rx", "tx";
#sound-dai-cells = <0>;
fsl,fifo-depth = <15>;
};
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