diff options
Diffstat (limited to 'Documentation/powerpc')
| -rw-r--r-- | Documentation/powerpc/dts-bindings/fsl/ssi.txt | 68 |
1 files changed, 39 insertions, 29 deletions
diff --git a/Documentation/powerpc/dts-bindings/fsl/ssi.txt b/Documentation/powerpc/dts-bindings/fsl/ssi.txt index 73133228893..5ff76c9c57d 100644 --- a/Documentation/powerpc/dts-bindings/fsl/ssi.txt +++ b/Documentation/powerpc/dts-bindings/fsl/ssi.txt @@ -4,46 +4,56 @@ The SSI is a serial device that communicates with audio codecs. It can be programmed in AC97, I2S, left-justified, or right-justified modes. Required properties: -- compatible : compatible list, containing "fsl,ssi" -- cell-index : the SSI, <0> = SSI1, <1> = SSI2, and so on -- reg : offset and length of the register set for the device -- interrupts : <a b> where a is the interrupt number and b is a - field that represents an encoding of the sense and - level information for the interrupt. This should be - encoded based on the information in section 2) - depending on the type of interrupt controller you - have. -- interrupt-parent : the phandle for the interrupt controller that - services interrupts for this device. -- fsl,mode : the operating mode for the SSI interface - "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" - l.j. mode, SSI is clock master - "rj-slave" - right-justified mode, SSI is clock slave - "rj-master" - r.j., SSI is clock master - "ac97-slave" - AC97 mode, SSI is clock slave - "ac97-master" - AC97 mode, SSI is clock master -- fsl,playback-dma: phandle to a node for the DMA channel to use for +- compatible: Compatible list, contains "fsl,ssi". +- cell-index: The SSI, <0> = SSI1, <1> = SSI2, and so on. +- reg: Offset and length of the register set for the device. +- interrupts: <a b> where a is the interrupt number and b is a + field that represents an encoding of the sense and + level information for the interrupt. This should be + encoded based on the information in section 2) + depending on the type of interrupt controller you + have. +- interrupt-parent: The phandle for the interrupt controller that + services interrupts for this device. +- fsl,mode: The operating mode for the SSI interface. + "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" - l.j. mode, SSI is clock master + "rj-slave" - right-justified mode, SSI is clock slave + "rj-master" - r.j., SSI is clock master + "ac97-slave" - AC97 mode, SSI is clock slave + "ac97-master" - AC97 mode, SSI is clock master +- fsl,playback-dma: Phandle to a node for the DMA channel to use for playback of audio. This is typically dictated by SOC design. See the notes below. -- fsl,capture-dma: phandle to a node for the DMA channel to use for +- fsl,capture-dma: Phandle to a node for the DMA channel to use for capture (recording) of audio. This is typically dictated by SOC design. See the notes below. -- fsl,fifo-depth: the number of elements in the transmit and receive FIFOs. +- fsl,fifo-depth: The number of elements in the transmit and receive FIFOs. This number is the maximum allowed value for SFCSR[TFWM0]. +- fsl,ssi-asynchronous: + 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. Optional properties: -- codec-handle : 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. +- codec-handle: 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. Child 'codec' node required properties: -- compatible : compatible list, contains the name of the codec +- compatible: Compatible list, contains the name of the codec Child 'codec' node optional properties: -- clock-frequency : The frequency of the input clock, which typically - comes from an on-board dedicated oscillator. +- clock-frequency: The frequency of the input clock, which typically comes + from an on-board dedicated oscillator. Notes on fsl,playback-dma and fsl,capture-dma: |