Re: [PATCH 3/4] dt-bindings: rtc: update stm32-rtc documentation for st,syscfg property
From: Rob Herring
Date: Thu Apr 26 2018 - 22:58:12 EST
On Thu, Apr 19, 2018 at 03:21:42PM +0200, Amelie Delaunay wrote:
> RTC driver should not be aware of the PWR registers offset and bits
> position. Furthermore, we can imagine that Disable Backup Protection (DBP)
> relative register and bit mask could change depending on the SoC. So this
> patch moves st,syscfg property from single pwrcfg phandle to pwrcfg
> phandle/offset/mask triplet.
> Signed-off-by: Amelie Delaunay <amelie.delaunay@xxxxxx>
> Documentation/devicetree/bindings/rtc/st,stm32-rtc.txt | 10 ++++++----
> 1 file changed, 6 insertions(+), 4 deletions(-)
> diff --git a/Documentation/devicetree/bindings/rtc/st,stm32-rtc.txt b/Documentation/devicetree/bindings/rtc/st,stm32-rtc.txt
> index a66692a..00f8b5d 100644
> --- a/Documentation/devicetree/bindings/rtc/st,stm32-rtc.txt
> +++ b/Documentation/devicetree/bindings/rtc/st,stm32-rtc.txt
> @@ -14,8 +14,10 @@ Required properties:
> It is required only on stm32h7.
> - interrupt-parent: phandle for the interrupt controller.
> - interrupts: rtc alarm interrupt.
> -- st,syscfg: phandle for pwrcfg, mandatory to disable/enable backup domain
> - (RTC registers) write protection.
> +- st,syscfg: phandle/offset/mask triplet. The phandle to pwrcfg used to
> + access control register at offset, and change the dbp (Disable Backup
> + Protection) bit represented by the mask, mandatory to disable/enable backup
> + domain (RTC registers) write protection.
It's fine to add this, but you are breaking compatibility in the driver
with existing DTBs by requiring these new fields.