Subject: Re: [PATCH] Added device tree binding for TDM and TDM phy

From: Scott Wood <[email-masked]>
Date: Wed, 9 Jan 2013 18:07:05 -0600

On 01/09/2013 01:10:24 AM, Singh Sandeep-B37400 wrote:
> A gentle reminder.
> Any comments are appreciated.
>=20
> Regards,
> Sandeep
>=20
> > -----Original Message-----
> > From: Singh Sandeep-B37400
> > Sent: Wednesday, January 02, 2013 6:55 PM
> > To: [email-masked]; [email-masked]
> > Cc: Singh Sandeep-B37400; Aggrwal Poonam-B10812
> > Subject: [PATCH] Added device tree binding for TDM and TDM phy
> >
> > This controller is available on many Freescale SOCs like MPC8315, =20
> P1020,
> > P1010 and P1022
> >
> > Signed-off-by: Sandeep Singh <[email-masked]>
> > Signed-off-by: Poonam Aggrwal <[email-masked]>
> > ---
> >  .../devicetree/bindings/powerpc/fsl/fsl-tdm.txt    |   63
> > ++++++++++++++++++++
> >  .../devicetree/bindings/powerpc/fsl/tdm-phy.txt    |   38 =20
> ++++++++++++
> >  2 files changed, 101 insertions(+), 0 deletions(-)  create mode =20
> 100644
> > Documentation/devicetree/bindings/powerpc/fsl/fsl-tdm.txt
> >  create mode 100644 =20
> Documentation/devicetree/bindings/powerpc/fsl/tdm-
> > phy.txt
> >
> > diff --git =20
> a/Documentation/devicetree/bindings/powerpc/fsl/fsl-tdm.txt
> > b/Documentation/devicetree/bindings/powerpc/fsl/fsl-tdm.txt
> > new file mode 100644
> > index 0000000..ceb2ef1
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/powerpc/fsl/fsl-tdm.txt
> > @@ -0,0 +1,63 @@
> > +TDM Device Tree Binding
> > +
> > +NOTE: The bindings described in this document are preliminary and
> > +subject to change.
> > +
> > +TDM (Time Division Multiplexing)
> > +
> > +Description:
> > +
> > +The TDM is full duplex serial port designed to allow various =20
> devices
> > +including digital signal processors (DSPs) to communicate with a
> > +variety of serial devices including industry standard framers, =20
> codecs,
> > other DSPs and microprocessors.
> > +
> > +The below properties describe the device tree bindings for =20
> Freescale
> > +TDM controller. This TDM controller is available on various =20
> Freescale
> > +Processors like MPC8315, P1020, P1022 and P1010.
> > +
> > +Required properties:
> > +
> > +- compatible
> > +    Value type: <string>
> > +    Definition: Should contain "fsl,tdm1.0".
> > +
> > +- reg
> > +    Definition: A standard property. The first reg specifier =20
> describes
> > the TDM
> > +    registers, and the second describes the TDM DMAC registers.
> > +
> > +- tdm_tx_clk
> > +    Value type: <u32 or u64>
> > +    Definition: This specifies the value of transmit clock. It =20
> should
> > not
> > +    exceed 50Mhz.
> > +
> > +- tdm_rx_clk
> > +    Value type: <u32 or u64>
> > +    Definition: This specifies the value of receive clock. Its =20
> value
> > could be
> > +    zero, in which case tdm will operate in shared mode. Its value
> > should not
> > +    exceed 50Mhz.

Please don't use underscores in property names, and use the vendor =20
prefix: "fsl,tdm-tx-clk" and "fsl,tdm-rx-clk".

> > diff --git =20
> a/Documentation/devicetree/bindings/powerpc/fsl/tdm-phy.txt
> > b/Documentation/devicetree/bindings/powerpc/fsl/tdm-phy.txt
> > new file mode 100644
> > index 0000000..2563934
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/powerpc/fsl/tdm-phy.txt
> > @@ -0,0 +1,38 @@
> > +TDM PHY Device Tree Binding
> > +
> > +NOTE: The bindings described in this document are preliminary and
> > +subject to change.
> > +
> > +Description:
> > +TDM PHY is the terminal interface of TDM subsystem. It is =20
> typically a
> > +line control device like E1/T1 framer or SLIC. A TDM device can =20
> have
> > +multiple TDM PHYs.
> > +
> > +Required properties:
> > +
> > +- compatible
> > +    Value type: <string>
> > +    Definition: Should contain generic compatibility like =20
> "tdm-phy-slic"
> > or
> > +    "tdm-phy-e1" or "tdm-phy-t1".

Does this "generic" string (plus the other properties) tell you all you =20
need to know about the device?  If there are other possible "generic" =20
compatibles, they should be listed or else different people will make =20
up different strings for the same thing.

-Scott=