Re: [PATCH V4 02/11] dt-bindings: clock: imx-lpcg: add support to parse clocks from device tree

[Stephen Boyd <sboyd@kernel.org>]

Quoting Dong Aisheng (2019-08-20 04:13:16)
> MX8QM and MX8QXP LPCG Clocks are mostly the same except they may reside
> in different subsystems across CPUs and also vary a bit on the availability.
> 
> Same as SCU clock, we want to move the clock definition into device tree
> which can fully decouple the dependency of Clock ID definition from device
> tree and make us be able to write a fully generic lpcg clock driver.
> 
> And we can also use the existence of clock nodes in device tree to address
> the device and clock availability differences across different SoCs.
> 
> Cc: Rob Herring <robh+dt@kernel.org>
> Cc: Stephen Boyd <sboyd@kernel.org>
> Cc: Shawn Guo <shawnguo@kernel.org>
> Cc: Sascha Hauer <kernel@pengutronix.de>
> Cc: Michael Turquette <mturquette@baylibre.com>
> Cc: devicetree@vger.kernel.org
> Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
> ---

Reviewed-by: Stephen Boyd <sboyd@kernel.org>

> ChangeLog:
> v3->v4:
>  * change bit-offset property to clock-indices
>  * use constant macro to define clock indinces
>  * drop hw-autogate property which is still not used by drivers
> v2->v3:
>  * no changes
> v1->v2:
>  * Update example
>  * Add power domain property
> ---
>  .../devicetree/bindings/clock/imx8qxp-lpcg.txt     | 36 ++++++++++++++++++----
>  include/dt-bindings/clock/imx8-lpcg.h              | 14 +++++++++
>  2 files changed, 44 insertions(+), 6 deletions(-)
>  create mode 100644 include/dt-bindings/clock/imx8-lpcg.h
> 
> diff --git a/Documentation/devicetree/bindings/clock/imx8qxp-lpcg.txt b/Documentation/devicetree/bindings/clock/imx8qxp-lpcg.txt
> index 965cfa4..cad8fc4 100644
> --- a/Documentation/devicetree/bindings/clock/imx8qxp-lpcg.txt
> +++ b/Documentation/devicetree/bindings/clock/imx8qxp-lpcg.txt
> @@ -11,6 +11,21 @@ enabled by these control bits, it might still not be running based
>  on the base resource.
>  
>  Required properties:
> +- compatible:          Should be one of:
> +                         "fsl,imx8qxp-lpcg"
> +                         "fsl,imx8qm-lpcg" followed by "fsl,imx8qxp-lpcg".
> +- reg:                 Address and length of the register set.
> +- #clock-cells:                Should be 1. One LPCG supports multiple clocks.
> +- clocks:              Input parent clocks phandle array for each clock.
> +- clock-indices:       An integer array indicating the bit offset for each clock.
> +                       Refer to <include/dt-bindings/clock/imx8-lpcg.h> for the
> +                       supported LPCG clock indices.

This is an interesting solution.

> +- clock-output-names:  Shall be the corresponding names of the outputs.
> +                       NOTE this property must be specified in the same order
> +                       as the clock-indices property.
> +- power-domains:       Should contain the power domain used by this clock.
> +
> +Legacy binding (DEPRECATED):
>  - compatible:  Should be one of:
>                   "fsl,imx8qxp-lpcg-adma",
>                   "fsl,imx8qxp-lpcg-conn",