[PATCH] powerpc: add fsl, fifo-depth property to Freescale SSI device nodes

[PATCH] powerpc: add fsl, fifo-depth property to Freescale SSI device nodes

[Timur Tabi]

The Freescale Serial Synchronous Interface (SSI) is an audio device present on
some Freescale SOCs.  Various implementations of the SSI have a different
transmit and receive FIFO depth, but are otherwise identical.  To support
these variations, add a new property fsl,fifo-depth to the SSI node that
specifies the depth of the FIFOs.

Also update the MPC8610 HPCD device tree with this property.

Signed-off-by: Timur Tabi <timur@freescale.com>
---

Updates to the SSI audio driver will come later.  Currently, this driver
supports only one Freescale SOC, and so it's hard-coded to use the value 8.
If/when this driver is updated to support other SOCs (e.g. the i.MX parts
that have a FIFO depth of 15), the driver will check for this property.  I
just want to get this DTS change in now.

 Documentation/powerpc/dts-bindings/fsl/ssi.txt |    2 ++
 arch/powerpc/boot/dts/mpc8610_hpcd.dts         |    2 ++
 2 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/Documentation/powerpc/dts-bindings/fsl/ssi.txt b/Documentation/powerpc/dts-bindings/fsl/ssi.txt
index a2d9639..7313322 100644
--- a/Documentation/powerpc/dts-bindings/fsl/ssi.txt
+++ b/Documentation/powerpc/dts-bindings/fsl/ssi.txt
@@ -30,6 +30,8 @@ Required properties:
 - 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.
+                    This number is the maximum allowed value for SFCSR[TFWM0].
 
 Optional properties:
 - codec-handle	  : phandle to a 'codec' node that defines an audio
diff --git a/arch/powerpc/boot/dts/mpc8610_hpcd.dts b/arch/powerpc/boot/dts/mpc8610_hpcd.dts
index f724d72..1bd3ebe 100644
--- a/arch/powerpc/boot/dts/mpc8610_hpcd.dts
+++ b/arch/powerpc/boot/dts/mpc8610_hpcd.dts
@@ -217,6 +217,7 @@
 			codec-handle = <&cs4270>;
 			fsl,playback-dma = <&dma00>;
 			fsl,capture-dma = <&dma01>;
+			fsl,fifo-depth = <8>;
 		};
 
 		ssi@16100 {
@@ -225,6 +226,7 @@
 			reg = <0x16100 0x100>;
 			interrupt-parent = <&mpic>;
 			interrupts = <63 2>;
+			fsl,fifo-depth = <8>;
 		};
 
 		dma@21300 {
-- 
1.6.1.3

Re: [PATCH] powerpc: add fsl, fifo-depth property to Freescale SSI device nodes

[Kumar Gala]

On Mar 4, 2009, at 2:55 PM, Timur Tabi wrote:

> The Freescale Serial Synchronous Interface (SSI) is an audio device  
> present on
> some Freescale SOCs.  Various implementations of the SSI have a  
> different
> transmit and receive FIFO depth, but are otherwise identical.  To  
> support
> these variations, add a new property fsl,fifo-depth to the SSI node  
> that
> specifies the depth of the FIFOs.
>
> Also update the MPC8610 HPCD device tree with this property.
>
> Signed-off-by: Timur Tabi <timur@freescale.com>
> ---
>
> Updates to the SSI audio driver will come later.  Currently, this  
> driver
> supports only one Freescale SOC, and so it's hard-coded to use the  
> value 8.
> If/when this driver is updated to support other SOCs (e.g. the i.MX  
> parts
> that have a FIFO depth of 15), the driver will check for this  
> property.  I
> just want to get this DTS change in now.
>
> Documentation/powerpc/dts-bindings/fsl/ssi.txt |    2 ++
> arch/powerpc/boot/dts/mpc8610_hpcd.dts         |    2 ++
> 2 files changed, 4 insertions(+), 0 deletions(-)

applied to next

- k