summaryrefslogtreecommitdiffstats
path: root/Documentation/powerpc
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/powerpc')
-rw-r--r--Documentation/powerpc/dts-bindings/fsl/ssi.txt68
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 731332288931..5ff76c9c57d2 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: