diff mbox

dmaengine: usb-dmac: Document SoC specific bindings

Message ID 1448331641-21758-1-git-send-email-horms+renesas@verge.net.au (mailing list archive)
State Superseded
Delegated to: Geert Uytterhoeven
Headers show

Commit Message

Simon Horman Nov. 24, 2015, 2:20 a.m. UTC
In general Renesas hardware is not documented to the extent where the
relationship between IP blocks on different SoCs can be assumed although
they may appear to operate the same way. Furthermore the documentation
typically does not specify a version for individual IP blocks. For these
reasons a convention of using the SoC name in place of a version and
providing SoC-specific compat strings has been adopted.

Although not universally liked this convention is used in the bindings for
most drivers for Renesas hardware. The purpose of this patch is to
update the Renesas USB DMA Controller driver to follow this convention.

Cc: devicetree@vger.kernel.org
Cc: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

---
* r8a7792 (R-Car V2H) is omitted as my reading of the documentation
  is that Renesas USB-DMAC does not exist on that SoC
* r8a7795 (R-Car H2) is omitted as its unclear to me on the compatibility
  of USB-DMAC that SoC

* Once this has been merged I intend to provide follow-up patches
  to use these new compat strings in the relevant dtsi files.
---
 Documentation/devicetree/bindings/dma/renesas,usb-dmac.txt | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

Comments

Yoshihiro Shimoda Nov. 24, 2015, 5:49 a.m. UTC | #1
Hi Simon-san,

> From: Simon Horman [mailto:horms+renesas@verge.net.au]
> Sent: Tuesday, November 24, 2015 11:21 AM
> 
> In general Renesas hardware is not documented to the extent where the
> relationship between IP blocks on different SoCs can be assumed although
> they may appear to operate the same way. Furthermore the documentation
> typically does not specify a version for individual IP blocks. For these
> reasons a convention of using the SoC name in place of a version and
> providing SoC-specific compat strings has been adopted.
> 
> Although not universally liked this convention is used in the bindings for
> most drivers for Renesas hardware. The purpose of this patch is to
> update the Renesas USB DMA Controller driver to follow this convention.
> 
> Cc: devicetree@vger.kernel.org
> Cc: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
> Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

Thank you for the patch!

> ---
> * r8a7792 (R-Car V2H) is omitted as my reading of the documentation
>   is that Renesas USB-DMAC does not exist on that SoC

I agree with you.

> * r8a7795 (R-Car H2) is omitted as its unclear to me on the compatibility
>   of USB-DMAC that SoC

I think this is R-Car H3, not H2.
Since R-Car H3's USB-DMAC is compatible with other SoCs,
would you add the R-Car H3's compatible string, if possible?

Anyway,
Acked-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>

Best regards,
Yoshihiro Shimoda

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Rob Herring Nov. 24, 2015, 8:16 p.m. UTC | #2
On Tue, Nov 24, 2015 at 11:20:41AM +0900, Simon Horman wrote:
> In general Renesas hardware is not documented to the extent where the
> relationship between IP blocks on different SoCs can be assumed although
> they may appear to operate the same way. Furthermore the documentation
> typically does not specify a version for individual IP blocks. For these
> reasons a convention of using the SoC name in place of a version and
> providing SoC-specific compat strings has been adopted.
> 
> Although not universally liked this convention is used in the bindings for
> most drivers for Renesas hardware. The purpose of this patch is to
> update the Renesas USB DMA Controller driver to follow this convention.
> 
> Cc: devicetree@vger.kernel.org
> Cc: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
> Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
> 
> ---
> * r8a7792 (R-Car V2H) is omitted as my reading of the documentation
>   is that Renesas USB-DMAC does not exist on that SoC
> * r8a7795 (R-Car H2) is omitted as its unclear to me on the compatibility
>   of USB-DMAC that SoC
> 
> * Once this has been merged I intend to provide follow-up patches
>   to use these new compat strings in the relevant dtsi files.
> ---
>  Documentation/devicetree/bindings/dma/renesas,usb-dmac.txt | 9 +++++++--
>  1 file changed, 7 insertions(+), 2 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/dma/renesas,usb-dmac.txt b/Documentation/devicetree/bindings/dma/renesas,usb-dmac.txt
> index 040f365954cc..3bb624e10615 100644
> --- a/Documentation/devicetree/bindings/dma/renesas,usb-dmac.txt
> +++ b/Documentation/devicetree/bindings/dma/renesas,usb-dmac.txt
> @@ -1,7 +1,12 @@
>  * Renesas USB DMA Controller Device Tree bindings
>  
>  Required Properties:
> -- compatible: must contain "renesas,usb-dmac"
> +- compatible: "renesas,usb-dmac-<soctype>", "renesas,usb-dmac" as fallback.
> +	      Examples with soctypes are:
> +		- "renesas,usb-dmac-r8a7790" (R-Car H2)
> +		- "renesas,usb-dmac-r8a7791" (R-Car M2-W)
> +		- "renesas,usb-dmac-r8a7793" (R-Car M2-N)
> +		- "renesas,usb-dmac-r8a7794" (R-Car E2)

Weren't you changing the order of SoC and block names on new bindings? 
Either way:

Acked-by: Rob Herring <robh@kernel.org>

Rob

>  - reg: base address and length of the registers block for the DMAC
>  - interrupts: interrupt specifiers for the DMAC, one for each entry in
>    interrupt-names.
> @@ -15,7 +20,7 @@ Required Properties:
>  Example: R8A7790 (R-Car H2) USB-DMACs
>  
>  	usb_dmac0: dma-controller@e65a0000 {
> -		compatible = "renesas,usb-dmac";
> +		compatible = "renesas,usb-dmac-r8a7790", "renesas,usb-dmac";
>  		reg = <0 0xe65a0000 0 0x100>;
>  		interrupts = <0 109 IRQ_TYPE_LEVEL_HIGH
>  			      0 109 IRQ_TYPE_LEVEL_HIGH>;
> -- 
> 2.1.4
> 
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Simon Horman Nov. 25, 2015, 12:20 a.m. UTC | #3
On Tue, Nov 24, 2015 at 02:16:55PM -0600, Rob Herring wrote:
> On Tue, Nov 24, 2015 at 11:20:41AM +0900, Simon Horman wrote:
> > In general Renesas hardware is not documented to the extent where the
> > relationship between IP blocks on different SoCs can be assumed although
> > they may appear to operate the same way. Furthermore the documentation
> > typically does not specify a version for individual IP blocks. For these
> > reasons a convention of using the SoC name in place of a version and
> > providing SoC-specific compat strings has been adopted.
> > 
> > Although not universally liked this convention is used in the bindings for
> > most drivers for Renesas hardware. The purpose of this patch is to
> > update the Renesas USB DMA Controller driver to follow this convention.
> > 
> > Cc: devicetree@vger.kernel.org
> > Cc: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
> > Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
> > 
> > ---
> > * r8a7792 (R-Car V2H) is omitted as my reading of the documentation
> >   is that Renesas USB-DMAC does not exist on that SoC
> > * r8a7795 (R-Car H2) is omitted as its unclear to me on the compatibility
> >   of USB-DMAC that SoC
> > 
> > * Once this has been merged I intend to provide follow-up patches
> >   to use these new compat strings in the relevant dtsi files.
> > ---
> >  Documentation/devicetree/bindings/dma/renesas,usb-dmac.txt | 9 +++++++--
> >  1 file changed, 7 insertions(+), 2 deletions(-)
> > 
> > diff --git a/Documentation/devicetree/bindings/dma/renesas,usb-dmac.txt b/Documentation/devicetree/bindings/dma/renesas,usb-dmac.txt
> > index 040f365954cc..3bb624e10615 100644
> > --- a/Documentation/devicetree/bindings/dma/renesas,usb-dmac.txt
> > +++ b/Documentation/devicetree/bindings/dma/renesas,usb-dmac.txt
> > @@ -1,7 +1,12 @@
> >  * Renesas USB DMA Controller Device Tree bindings
> >  
> >  Required Properties:
> > -- compatible: must contain "renesas,usb-dmac"
> > +- compatible: "renesas,usb-dmac-<soctype>", "renesas,usb-dmac" as fallback.
> > +	      Examples with soctypes are:
> > +		- "renesas,usb-dmac-r8a7790" (R-Car H2)
> > +		- "renesas,usb-dmac-r8a7791" (R-Car M2-W)
> > +		- "renesas,usb-dmac-r8a7793" (R-Car M2-N)
> > +		- "renesas,usb-dmac-r8a7794" (R-Car E2)
> 
> Weren't you changing the order of SoC and block names on new bindings? 

Could you clarify what the desired order is?
My intention is for these bindings to use the preferred order.

> Either way:
> 
> Acked-by: Rob Herring <robh@kernel.org>
> 
> Rob
> 
> >  - reg: base address and length of the registers block for the DMAC
> >  - interrupts: interrupt specifiers for the DMAC, one for each entry in
> >    interrupt-names.
> > @@ -15,7 +20,7 @@ Required Properties:
> >  Example: R8A7790 (R-Car H2) USB-DMACs
> >  
> >  	usb_dmac0: dma-controller@e65a0000 {
> > -		compatible = "renesas,usb-dmac";
> > +		compatible = "renesas,usb-dmac-r8a7790", "renesas,usb-dmac";
> >  		reg = <0 0xe65a0000 0 0x100>;
> >  		interrupts = <0 109 IRQ_TYPE_LEVEL_HIGH
> >  			      0 109 IRQ_TYPE_LEVEL_HIGH>;
> > -- 
> > 2.1.4
> > 
> > --
> > To unsubscribe from this list: send the line "unsubscribe devicetree" in
> > the body of a message to majordomo@vger.kernel.org
> > More majordomo info at  http://vger.kernel.org/majordomo-info.html
> 
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Simon Horman Nov. 25, 2015, 12:21 a.m. UTC | #4
On Tue, Nov 24, 2015 at 05:49:05AM +0000, Yoshihiro Shimoda wrote:
> Hi Simon-san,
> 
> > From: Simon Horman [mailto:horms+renesas@verge.net.au]
> > Sent: Tuesday, November 24, 2015 11:21 AM
> > 
> > In general Renesas hardware is not documented to the extent where the
> > relationship between IP blocks on different SoCs can be assumed although
> > they may appear to operate the same way. Furthermore the documentation
> > typically does not specify a version for individual IP blocks. For these
> > reasons a convention of using the SoC name in place of a version and
> > providing SoC-specific compat strings has been adopted.
> > 
> > Although not universally liked this convention is used in the bindings for
> > most drivers for Renesas hardware. The purpose of this patch is to
> > update the Renesas USB DMA Controller driver to follow this convention.
> > 
> > Cc: devicetree@vger.kernel.org
> > Cc: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
> > Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
> 
> Thank you for the patch!
> 
> > ---
> > * r8a7792 (R-Car V2H) is omitted as my reading of the documentation
> >   is that Renesas USB-DMAC does not exist on that SoC
> 
> I agree with you.
> 
> > * r8a7795 (R-Car H2) is omitted as its unclear to me on the compatibility
> >   of USB-DMAC that SoC
> 
> I think this is R-Car H3, not H2.

Yes, H3. Sorry about that.

> Since R-Car H3's USB-DMAC is compatible with other SoCs,
> would you add the R-Car H3's compatible string, if possible?

Sure, will do.

> Anyway,
> Acked-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>

Thanks!
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Simon Horman Dec. 1, 2015, 6:47 a.m. UTC | #5
Hi Rob,

On Wed, Nov 25, 2015 at 09:20:32AM +0900, Simon Horman wrote:
> On Tue, Nov 24, 2015 at 02:16:55PM -0600, Rob Herring wrote:
> > On Tue, Nov 24, 2015 at 11:20:41AM +0900, Simon Horman wrote:
> > > In general Renesas hardware is not documented to the extent where the
> > > relationship between IP blocks on different SoCs can be assumed although
> > > they may appear to operate the same way. Furthermore the documentation
> > > typically does not specify a version for individual IP blocks. For these
> > > reasons a convention of using the SoC name in place of a version and
> > > providing SoC-specific compat strings has been adopted.
> > > 
> > > Although not universally liked this convention is used in the bindings for
> > > most drivers for Renesas hardware. The purpose of this patch is to
> > > update the Renesas USB DMA Controller driver to follow this convention.
> > > 
> > > Cc: devicetree@vger.kernel.org
> > > Cc: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
> > > Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
> > > 
> > > ---
> > > * r8a7792 (R-Car V2H) is omitted as my reading of the documentation
> > >   is that Renesas USB-DMAC does not exist on that SoC
> > > * r8a7795 (R-Car H2) is omitted as its unclear to me on the compatibility
> > >   of USB-DMAC that SoC
> > > 
> > > * Once this has been merged I intend to provide follow-up patches
> > >   to use these new compat strings in the relevant dtsi files.
> > > ---
> > >  Documentation/devicetree/bindings/dma/renesas,usb-dmac.txt | 9 +++++++--
> > >  1 file changed, 7 insertions(+), 2 deletions(-)
> > > 
> > > diff --git a/Documentation/devicetree/bindings/dma/renesas,usb-dmac.txt b/Documentation/devicetree/bindings/dma/renesas,usb-dmac.txt
> > > index 040f365954cc..3bb624e10615 100644
> > > --- a/Documentation/devicetree/bindings/dma/renesas,usb-dmac.txt
> > > +++ b/Documentation/devicetree/bindings/dma/renesas,usb-dmac.txt
> > > @@ -1,7 +1,12 @@
> > >  * Renesas USB DMA Controller Device Tree bindings
> > >  
> > >  Required Properties:
> > > -- compatible: must contain "renesas,usb-dmac"
> > > +- compatible: "renesas,usb-dmac-<soctype>", "renesas,usb-dmac" as fallback.
> > > +	      Examples with soctypes are:
> > > +		- "renesas,usb-dmac-r8a7790" (R-Car H2)
> > > +		- "renesas,usb-dmac-r8a7791" (R-Car M2-W)
> > > +		- "renesas,usb-dmac-r8a7793" (R-Car M2-N)
> > > +		- "renesas,usb-dmac-r8a7794" (R-Car E2)
> > 
> > Weren't you changing the order of SoC and block names on new bindings? 
> 
> Could you clarify what the desired order is?
> My intention is for these bindings to use the preferred order.

ping
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Geert Uytterhoeven Dec. 1, 2015, 8:33 a.m. UTC | #6
On Tue, Dec 1, 2015 at 7:47 AM, Simon Horman <horms@verge.net.au> wrote:
> On Wed, Nov 25, 2015 at 09:20:32AM +0900, Simon Horman wrote:
>> On Tue, Nov 24, 2015 at 02:16:55PM -0600, Rob Herring wrote:
>> > On Tue, Nov 24, 2015 at 11:20:41AM +0900, Simon Horman wrote:
>> > > In general Renesas hardware is not documented to the extent where the
>> > > relationship between IP blocks on different SoCs can be assumed although
>> > > they may appear to operate the same way. Furthermore the documentation
>> > > typically does not specify a version for individual IP blocks. For these
>> > > reasons a convention of using the SoC name in place of a version and
>> > > providing SoC-specific compat strings has been adopted.
>> > >
>> > > Although not universally liked this convention is used in the bindings for
>> > > most drivers for Renesas hardware. The purpose of this patch is to
>> > > update the Renesas USB DMA Controller driver to follow this convention.
>> > >
>> > > Cc: devicetree@vger.kernel.org
>> > > Cc: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
>> > > Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
>> > >
>> > > ---
>> > > * r8a7792 (R-Car V2H) is omitted as my reading of the documentation
>> > >   is that Renesas USB-DMAC does not exist on that SoC
>> > > * r8a7795 (R-Car H2) is omitted as its unclear to me on the compatibility
>> > >   of USB-DMAC that SoC
>> > >
>> > > * Once this has been merged I intend to provide follow-up patches
>> > >   to use these new compat strings in the relevant dtsi files.
>> > > ---
>> > >  Documentation/devicetree/bindings/dma/renesas,usb-dmac.txt | 9 +++++++--
>> > >  1 file changed, 7 insertions(+), 2 deletions(-)
>> > >
>> > > diff --git a/Documentation/devicetree/bindings/dma/renesas,usb-dmac.txt b/Documentation/devicetree/bindings/dma/renesas,usb-dmac.txt
>> > > index 040f365954cc..3bb624e10615 100644
>> > > --- a/Documentation/devicetree/bindings/dma/renesas,usb-dmac.txt
>> > > +++ b/Documentation/devicetree/bindings/dma/renesas,usb-dmac.txt
>> > > @@ -1,7 +1,12 @@
>> > >  * Renesas USB DMA Controller Device Tree bindings
>> > >
>> > >  Required Properties:
>> > > -- compatible: must contain "renesas,usb-dmac"
>> > > +- compatible: "renesas,usb-dmac-<soctype>", "renesas,usb-dmac" as fallback.
>> > > +       Examples with soctypes are:
>> > > +         - "renesas,usb-dmac-r8a7790" (R-Car H2)
>> > > +         - "renesas,usb-dmac-r8a7791" (R-Car M2-W)
>> > > +         - "renesas,usb-dmac-r8a7793" (R-Car M2-N)
>> > > +         - "renesas,usb-dmac-r8a7794" (R-Car E2)
>> >
>> > Weren't you changing the order of SoC and block names on new bindings?
>>
>> Could you clarify what the desired order is?
>> My intention is for these bindings to use the preferred order.
>
> ping

Not speaking for Rob, but I think he means e.g. "renesas,r8a7790-usb-dmac".

Gr{oetje,eeting}s,

                        Geert

--
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In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds
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Simon Horman Dec. 2, 2015, 12:54 a.m. UTC | #7
On Tue, Dec 01, 2015 at 09:33:09AM +0100, Geert Uytterhoeven wrote:
> On Tue, Dec 1, 2015 at 7:47 AM, Simon Horman <horms@verge.net.au> wrote:
> > On Wed, Nov 25, 2015 at 09:20:32AM +0900, Simon Horman wrote:
> >> On Tue, Nov 24, 2015 at 02:16:55PM -0600, Rob Herring wrote:
> >> > On Tue, Nov 24, 2015 at 11:20:41AM +0900, Simon Horman wrote:
> >> > > In general Renesas hardware is not documented to the extent where the
> >> > > relationship between IP blocks on different SoCs can be assumed although
> >> > > they may appear to operate the same way. Furthermore the documentation
> >> > > typically does not specify a version for individual IP blocks. For these
> >> > > reasons a convention of using the SoC name in place of a version and
> >> > > providing SoC-specific compat strings has been adopted.
> >> > >
> >> > > Although not universally liked this convention is used in the bindings for
> >> > > most drivers for Renesas hardware. The purpose of this patch is to
> >> > > update the Renesas USB DMA Controller driver to follow this convention.
> >> > >
> >> > > Cc: devicetree@vger.kernel.org
> >> > > Cc: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
> >> > > Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
> >> > >
> >> > > ---
> >> > > * r8a7792 (R-Car V2H) is omitted as my reading of the documentation
> >> > >   is that Renesas USB-DMAC does not exist on that SoC
> >> > > * r8a7795 (R-Car H2) is omitted as its unclear to me on the compatibility
> >> > >   of USB-DMAC that SoC
> >> > >
> >> > > * Once this has been merged I intend to provide follow-up patches
> >> > >   to use these new compat strings in the relevant dtsi files.
> >> > > ---
> >> > >  Documentation/devicetree/bindings/dma/renesas,usb-dmac.txt | 9 +++++++--
> >> > >  1 file changed, 7 insertions(+), 2 deletions(-)
> >> > >
> >> > > diff --git a/Documentation/devicetree/bindings/dma/renesas,usb-dmac.txt b/Documentation/devicetree/bindings/dma/renesas,usb-dmac.txt
> >> > > index 040f365954cc..3bb624e10615 100644
> >> > > --- a/Documentation/devicetree/bindings/dma/renesas,usb-dmac.txt
> >> > > +++ b/Documentation/devicetree/bindings/dma/renesas,usb-dmac.txt
> >> > > @@ -1,7 +1,12 @@
> >> > >  * Renesas USB DMA Controller Device Tree bindings
> >> > >
> >> > >  Required Properties:
> >> > > -- compatible: must contain "renesas,usb-dmac"
> >> > > +- compatible: "renesas,usb-dmac-<soctype>", "renesas,usb-dmac" as fallback.
> >> > > +       Examples with soctypes are:
> >> > > +         - "renesas,usb-dmac-r8a7790" (R-Car H2)
> >> > > +         - "renesas,usb-dmac-r8a7791" (R-Car M2-W)
> >> > > +         - "renesas,usb-dmac-r8a7793" (R-Car M2-N)
> >> > > +         - "renesas,usb-dmac-r8a7794" (R-Car E2)
> >> >
> >> > Weren't you changing the order of SoC and block names on new bindings?
> >>
> >> Could you clarify what the desired order is?
> >> My intention is for these bindings to use the preferred order.
> >
> > ping
> 
> Not speaking for Rob, but I think he means e.g. "renesas,r8a7790-usb-dmac".

Thanks. Reviewing previous emails I see that now.
I will see about making it so.
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diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/dma/renesas,usb-dmac.txt b/Documentation/devicetree/bindings/dma/renesas,usb-dmac.txt
index 040f365954cc..3bb624e10615 100644
--- a/Documentation/devicetree/bindings/dma/renesas,usb-dmac.txt
+++ b/Documentation/devicetree/bindings/dma/renesas,usb-dmac.txt
@@ -1,7 +1,12 @@ 
 * Renesas USB DMA Controller Device Tree bindings
 
 Required Properties:
-- compatible: must contain "renesas,usb-dmac"
+- compatible: "renesas,usb-dmac-<soctype>", "renesas,usb-dmac" as fallback.
+	      Examples with soctypes are:
+		- "renesas,usb-dmac-r8a7790" (R-Car H2)
+		- "renesas,usb-dmac-r8a7791" (R-Car M2-W)
+		- "renesas,usb-dmac-r8a7793" (R-Car M2-N)
+		- "renesas,usb-dmac-r8a7794" (R-Car E2)
 - reg: base address and length of the registers block for the DMAC
 - interrupts: interrupt specifiers for the DMAC, one for each entry in
   interrupt-names.
@@ -15,7 +20,7 @@  Required Properties:
 Example: R8A7790 (R-Car H2) USB-DMACs
 
 	usb_dmac0: dma-controller@e65a0000 {
-		compatible = "renesas,usb-dmac";
+		compatible = "renesas,usb-dmac-r8a7790", "renesas,usb-dmac";
 		reg = <0 0xe65a0000 0 0x100>;
 		interrupts = <0 109 IRQ_TYPE_LEVEL_HIGH
 			      0 109 IRQ_TYPE_LEVEL_HIGH>;