[PATCH v3 02/12] dt-bindings: clock: r9a08g045-vbattb: Add clock IDs for the VBATTB controller

[Rob Herring]

On Fri, Aug 30, 2024 at 04:02:08PM +0300, Claudiu wrote:
> From: Claudiu Beznea <claudiu.beznea.uj at bp.renesas.com>
> 
> The VBATTB controllers controls the clock for the RTC on the Renesas
> RZ/G3S. The HW block diagram for the clock logic is as follows:
> 
>            +----------+ XC   `\
> RTXIN  --->|          |----->| \       +----+  VBATTCLK
>            | 32K clock|      |  |----->|gate|----------->
> 	   | osc      | XBYP |  |      +----+
> RTXOUT --->|          |----->| /
>            +----------+      ,/
> 
> One could connect as input to this HW block either a crystal oscillator or
> an external clock device.
> 
> After discussions w/ Stephen Boyd the clock tree associated with this
> hardware block was exported in Linux as:
> 
> input-xtal
>   xbyp
>   xc
>      mux
>         vbattclk
> 
> where:
> - input-xtal is the input clock (connected to RTXIN, RTXOUT pins)
> - xc, xbyp are mux inputs
> - mux is the internal mux
> - vbattclk is the gate clock that feeds in the end the RTC
> 
> to allow selecting the input of the MUX though assigned-clock DT
> properties, using the already existing clock drivers and avoid adding
> other DT properties.
> 
> This allows select the input of the mux based on the type of the
> connected input clock:
> - if the 32768 crystal oscillator is connected as input for the VBATTB,
>   the input of the mux should be xc
> - if an external clock device is connected as input for the VBATTB the
>   input of the mux should be xbyp
> 
> Add clock IDs for the VBATTB controller.
> 
> Signed-off-by: Claudiu Beznea <claudiu.beznea.uj at bp.renesas.com>
> ---
> 
> Changes in v3:
> - none; this patch is new
> 
>  include/dt-bindings/clock/r9a08g045-vbattb.h | 13 +++++++++++++
>  1 file changed, 13 insertions(+)
>  create mode 100644 include/dt-bindings/clock/r9a08g045-vbattb.h

Squash this into the previous patch. It is part of the binding.

Rob