Re: [PATCH v3 1/3] dt-bindings: watchdog: sunxi: Add compatibles for R329

Guenter Roeck
2021-09-04T15:10:52Z

On Thu, Sep 02, 2021 at 05:57:48PM -0500, Samuel Holland wrote:
> On existing SoCs, the watchdog has a single clock input: HOSC (OSC24M)
> divided by 750. However, starting with R329, LOSC (OSC32k) is added as
> an alternative clock source, with a bit to switch between them.
>
> Since 24 MHz / 750 == 32 kHz, not 32.768 kHz, the hardware adjusts the
> cycle counts to keep the timeouts independent of the clock source. This
> keeps the programming interface backward-compatible.
>
> Furthermore, the R329 has two watchdogs: one for use by the ARM CPUs
> at 0x20000a0, and a second one for use by the DSPs at 0x7020400. The
> first of these adds two more new registers, to allow software to
> immediately assert the SoC reset signal. Add an additional "-reset"
> suffix to signify the presence of this feature.
>
> Signed-off-by: Samuel Holland <samuel@sholland.org>
> Acked-by: Maxime Ripard <maxime@cerno.tech>
> Reviewed-by: Rob Herring <robh@kernel.org>

Acked-by: Guenter Roeck <linux@roeck-us.net>

> ---
> Changes v2 to v3:
> - Add else case
> - Add additional allwinner,sun50i-r329-wdt-reset compatible
> Changes v1 to v2:
> - Switch clock-names from enum to const
> - Add descriptions to "clocks" items
>
> .../watchdog/allwinner,sun4i-a10-wdt.yaml | 42 ++++++++++++++++++-
> 1 file changed, 41 insertions(+), 1 deletion(-)
>
> diff --git a/Documentation/devicetree/bindings/watchdog/allwinner,sun4i-a10-wdt.yaml b/Documentation/devicetree/bindings/watchdog/allwinner,sun4i-a10-wdt.yaml
> index 9aa3c313c49f..877f47759814 100644
> --- a/Documentation/devicetree/bindings/watchdog/allwinner,sun4i-a10-wdt.yaml
> +++ b/Documentation/devicetree/bindings/watchdog/allwinner,sun4i-a10-wdt.yaml
> @@ -24,6 +24,8 @@ properties:
> - allwinner,sun50i-a100-wdt
> - allwinner,sun50i-h6-wdt
> - allwinner,sun50i-h616-wdt
> + - allwinner,sun50i-r329-wdt
> + - allwinner,sun50i-r329-wdt-reset
> - const: allwinner,sun6i-a31-wdt
> - items:
> - const: allwinner,suniv-f1c100s-wdt
> @@ -33,7 +35,18 @@ properties:
> maxItems: 1
>
> clocks:
> - maxItems: 1
> + minItems: 1
> + maxItems: 2
> + items:
> + - description: High-frequency oscillator input, divided internally
> + - description: Low-frequency oscillator input, only found on some variants
> +
> + clock-names:
> + minItems: 1
> + maxItems: 2
> + items:
> + - const: hosc
> + - const: losc
>
> interrupts:
> maxItems: 1
> @@ -44,6 +57,33 @@ required:
> - clocks
> - interrupts
>
> +if:
> + properties:
> + compatible:
> + contains:
> + enum:
> + - allwinner,sun50i-r329-wdt
> + - allwinner,sun50i-r329-wdt-reset
> +
> +then:
> + properties:
> + clocks:
> + minItems: 2
> +
> + clock-names:
> + minItems: 2
> +
> + required:
> + - clock-names
> +
> +else:
> + properties:
> + clocks:
> + maxItems: 1
> +
> + clock-names:
> + maxItems: 1
> +
> unevaluatedProperties: false
>