Re: [PATCH v4 5/6] spmi: document the PMIC arbiter SPMI bindings

[Courtney Cavin <courtney.cavin@sonymobile.com>]

On Tue, Jan 14, 2014 at 07:41:39PM +0100, Josh Cartwright wrote:
> Signed-off-by: Josh Cartwright <joshc@codeaurora.org>
> ---
>  .../bindings/spmi/qcom,spmi-pmic-arb.txt           | 46 ++++++++++++++++++++++
>  1 file changed, 46 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/spmi/qcom,spmi-pmic-arb.txt
> 
> diff --git a/Documentation/devicetree/bindings/spmi/qcom,spmi-pmic-arb.txt b/Documentation/devicetree/bindings/spmi/qcom,spmi-pmic-arb.txt
> new file mode 100644
> index 0000000..9e50cb3
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/spmi/qcom,spmi-pmic-arb.txt
> @@ -0,0 +1,46 @@
> +Qualcomm SPMI Controller (PMIC Arbiter)
> +
> +The SPMI PMIC Arbiter is found on the Snapdragon 800 Series.  It is an SPMI
> +controller with wrapping arbitration logic to allow for multiple on-chip
> +devices to control a single SPMI master.
> +
> +The PMIC Arbiter can also act as an interrupt controller, providing interrupts
> +to slave devices.
> +
> +See spmi.txt for the generic SPMI controller binding requirements for child
> +nodes.
> +
> +Required properties:
> +- compatible : should be "qcom,spmi-pmic-arb".
> +- reg-names  : should be "core", "intr", "cnfg"
> +- reg : register specifiers, must contain 3 entries, in the follow order:
> +     core registers, interrupt controller registers, configuration registers

As far as I can tell, patch 3/6 doesn't require these to be in any
order, as it uses 'reg-names' to fetch the values. Perhaps the
following:

reg-names : must contain:
	"core" - core registers
	"intr" - interrupt controller registers
	"cnfg" - configuration registers
reg : A list of address + size pairs for the regs listed in reg-names

> +- #address-cells : must be set to 2
> +- #size-cells : must be set to 0
> +- qcom,ee : indicates the active Execution Environment identifier (0-5)
> +- qcom,channel : which of the PMIC Arb provided channels to use for accesses (0-5)

These two are new.... Is it expected that they should be required?

> +- interrupt-controller : indicates the PMIC arbiter is an interrupt controller

Although it's probably fairly understood that this is a boolean, it
wouldn't hurt to mention that here.  It might also be worth referencing
devicetree/binding/interrupt-controller/interrupts.txt in your opening
blurb.

> +- #interrupt-cells = <4>:  interrupts are specified as a 4-tuple:

Nitpick: This '= <X>' differs from the above 'must be set to X' format.

> +    cell 1: slave ID for the requested interrupt (0-15)
> +    cell 2: peripheral ID for requested interrupt (0-255)
> +    cell 3: the requested peripheral interrupt (0-7)
> +    cell 4: interrupt flags indicating level-sense information, as defined in
> +            dt-bindings/interrupt-controller/irq.h
[...]

-Courtney