[PATCH 0/6] rtc: rzn1: cleanups, no irq support, R-Car Gen5 enablement

[PATCH 0/6] rtc: rzn1: cleanups, no irq support, R-Car Gen5 enablement

[Wolfram Sang]

The main intention of this series is to enable RTC support for the
Renesas R-Car Gen5 X5H SoC (patches 5+6). Because interrupts are not
wired there, patches to make interrupts optional are included (patches
3+4). Some cleanups I came up with are prepended (patches 1+2).

These patches have been tested on the original RZ/N1D board and the new
X5H Ironhide board. 'rtctest' passed on both SoCs. On X5H, some tests
are skipped, of course, because no alarms are supported.

'dt_binding_check' and 'dtbs_check' also did not find any issues.

A branch can be found here:

git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux.git renesas/x5h/rtc-experimental

Looking forward to comments.


Wolfram Sang (6):
  dt-bindings: rtc: rzn1: drop unneeded 'start-year' from example
  dt-bindings: rtc: rzn1: add SoC names next to their IDs
  dt-bindings: rtc: rzn1: interrupts are not required
  rtc: rzn1: make interrupts optional
  dt-bindings: rtc: rzn1: add R-Car X5H support
  rtc: rzn1: add R-Car X5H support

 .../bindings/rtc/renesas,rzn1-rtc.yaml        | 19 +++---
 drivers/rtc/rtc-rzn1.c                        | 59 +++++++++----------
 2 files changed, 38 insertions(+), 40 deletions(-)

-- 
2.53.0

[PATCH 1/6] dt-bindings: rtc: rzn1: drop unneeded 'start-year' from example

[Wolfram Sang]

We don't use 'start-year' in upstream DTs because the driver does the
right thing by default, ranging from 2000 to 2099. So, drop it from the
example, too.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
---
 Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml | 1 -
 1 file changed, 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml b/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml
index ea7b039a91e7..e96007981c34 100644
--- a/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml
+++ b/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml
@@ -91,5 +91,4 @@ examples:
         clocks = <&sysctrl R9A06G032_HCLK_RTC>;
         clock-names = "hclk";
         power-domains = <&sysctrl>;
-        start-year = <2000>;
     };
-- 
2.53.0

[PATCH 2/6] dt-bindings: rtc: rzn1: add SoC names next to their IDs

[Wolfram Sang]

This helps maintaining because the numbers are easy to confuse.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
---
 .../devicetree/bindings/rtc/renesas,rzn1-rtc.yaml      | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml b/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml
index e96007981c34..7ea77cd0bee1 100644
--- a/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml
+++ b/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml
@@ -14,14 +14,14 @@ properties:
     oneOf:
       - items:
           - enum:
-              - renesas,r9a06g032-rtc
-          - const: renesas,rzn1-rtc
+              - renesas,r9a06g032-rtc # RZ/N1D
+          - const: renesas,rzn1-rtc   # RZ/N1
 
-      - const: renesas,r9a09g077-rtc
+      - const: renesas,r9a09g077-rtc  # RZ/T2H
 
       - items:
-          - const: renesas,r9a09g087-rtc
-          - const: renesas,r9a09g077-rtc
+          - const: renesas,r9a09g087-rtc  # RZ/N2H
+          - const: renesas,r9a09g077-rtc  # RZ/T2H
 
   reg:
     maxItems: 1
-- 
2.53.0

[PATCH 3/6] dt-bindings: rtc: rzn1: interrupts are not required

[Wolfram Sang]

Interrupts are only needed for alarms to work. Reading/Setting the RTC
works fine without interrupts. Drop the requirement for interrupts
because an upcoming SoC does not have interrupts wired.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
---
 Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml | 2 --
 1 file changed, 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml b/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml
index 7ea77cd0bee1..b426a34958d6 100644
--- a/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml
+++ b/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml
@@ -52,8 +52,6 @@ properties:
 required:
   - compatible
   - reg
-  - interrupts
-  - interrupt-names
   - clocks
   - clock-names
   - power-domains
-- 
2.53.0

[PATCH 4/6] rtc: rzn1: make interrupts optional

[Wolfram Sang]

If no interrupts are specified, alarm handling will just be disabled. No
need to bail out. Instead of juggling with 4 different static rtc_ops
for all {subu|scmp}_{no_}alarm cases, a single non-static rtc_ops is
chosen which is adapted during probe().

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
---
 drivers/rtc/rtc-rzn1.c | 58 +++++++++++++++++++-----------------------
 1 file changed, 26 insertions(+), 32 deletions(-)

diff --git a/drivers/rtc/rtc-rzn1.c b/drivers/rtc/rtc-rzn1.c
index b9d69ebdd224..ebb56c8d75ea 100644
--- a/drivers/rtc/rtc-rzn1.c
+++ b/drivers/rtc/rtc-rzn1.c
@@ -378,22 +378,9 @@ static int rzn1_rtc_set_offset(struct device *dev, long offset)
 	return 0;
 }
 
-static const struct rtc_class_ops rzn1_rtc_ops_subu = {
+static struct rtc_class_ops rzn1_rtc_ops = {
 	.read_time = rzn1_rtc_read_time,
 	.set_time = rzn1_rtc_set_time,
-	.read_alarm = rzn1_rtc_read_alarm,
-	.set_alarm = rzn1_rtc_set_alarm,
-	.alarm_irq_enable = rzn1_rtc_alarm_irq_enable,
-	.read_offset = rzn1_rtc_read_offset,
-	.set_offset = rzn1_rtc_set_offset,
-};
-
-static const struct rtc_class_ops rzn1_rtc_ops_scmp = {
-	.read_time = rzn1_rtc_read_time,
-	.set_time = rzn1_rtc_set_time,
-	.read_alarm = rzn1_rtc_read_alarm,
-	.set_alarm = rzn1_rtc_set_alarm,
-	.alarm_irq_enable = rzn1_rtc_alarm_irq_enable,
 };
 
 static void rzn1_rtc_disable_hardware(void *data)
@@ -431,14 +418,11 @@ static int rzn1_rtc_probe(struct platform_device *pdev)
 	if (IS_ERR(rtc->base))
 		return dev_err_probe(dev, PTR_ERR(rtc->base), "Missing reg\n");
 
-	irq = platform_get_irq_byname(pdev, "alarm");
-	if (irq < 0)
-		return irq;
-
 	rtc->rtcdev = devm_rtc_allocate_device(dev);
 	if (IS_ERR(rtc->rtcdev))
 		return PTR_ERR(rtc->rtcdev);
 
+	rtc->rtcdev->ops = &rzn1_rtc_ops;
 	rtc->rtcdev->range_min = RTC_TIMESTAMP_BEGIN_2000;
 	rtc->rtcdev->range_max = RTC_TIMESTAMP_END_2099;
 	rtc->rtcdev->alarm_offset_max = 7 * 86400;
@@ -490,9 +474,9 @@ static int rzn1_rtc_probe(struct platform_device *pdev)
 
 	if (scmp_val) {
 		writel(rate - 1, rtc->base + RZN1_RTC_SCMP);
-		rtc->rtcdev->ops = &rzn1_rtc_ops_scmp;
 	} else {
-		rtc->rtcdev->ops = &rzn1_rtc_ops_subu;
+		rzn1_rtc_ops.read_offset = rzn1_rtc_read_offset;
+		rzn1_rtc_ops.set_offset = rzn1_rtc_set_offset;
 	}
 
 	/* Enable controller finally */
@@ -503,20 +487,30 @@ static int rzn1_rtc_probe(struct platform_device *pdev)
 
 	spin_lock_init(&rtc->ctl1_access_lock);
 
-	ret = devm_request_irq(dev, irq, rzn1_rtc_alarm_irq, 0, "RZN1 RTC Alarm", rtc);
-	if (ret)
-		return dev_err_probe(dev, ret, "RTC alarm interrupt not available\n");
 
-	irq = platform_get_irq_byname_optional(pdev, "pps");
-	if (irq == -EPROBE_DEFER)
+	irq = platform_get_irq_byname_optional(pdev, "alarm");
+	if (irq == -EPROBE_DEFER) {
 		return irq;
-	if (irq >= 0)
-		ret = devm_request_irq(dev, irq, rzn1_rtc_1s_irq, 0, "RZN1 RTC 1s", rtc);
-
-	if (irq < 0 || ret) {
-		set_bit(RTC_FEATURE_ALARM_RES_MINUTE, rtc->rtcdev->features);
-		clear_bit(RTC_FEATURE_UPDATE_INTERRUPT, rtc->rtcdev->features);
-		dev_warn(dev, "RTC pps interrupt not available. Alarm has only minute accuracy\n");
+	} else if (irq >= 0) {
+		ret = devm_request_irq(dev, irq, rzn1_rtc_alarm_irq, 0, "RZN1 RTC Alarm", rtc);
+		if (ret)
+			return dev_err_probe(dev, ret, "RTC alarm interrupt not available\n");
+
+		irq = platform_get_irq_byname_optional(pdev, "pps");
+		if (irq == -EPROBE_DEFER)
+			return irq;
+		if (irq >= 0)
+			ret = devm_request_irq(dev, irq, rzn1_rtc_1s_irq, 0, "RZN1 RTC 1s", rtc);
+
+		if (irq < 0 || ret) {
+			set_bit(RTC_FEATURE_ALARM_RES_MINUTE, rtc->rtcdev->features);
+			clear_bit(RTC_FEATURE_UPDATE_INTERRUPT, rtc->rtcdev->features);
+			dev_warn(dev, "RTC pps interrupt not available. Alarm has only minute accuracy\n");
+		}
+
+		rzn1_rtc_ops.read_alarm = rzn1_rtc_read_alarm;
+		rzn1_rtc_ops.set_alarm = rzn1_rtc_set_alarm;
+		rzn1_rtc_ops.alarm_irq_enable = rzn1_rtc_alarm_irq_enable;
 	}
 
 	return devm_rtc_register_device(rtc->rtcdev);
-- 
2.53.0

[PATCH 5/6] dt-bindings: rtc: rzn1: add R-Car X5H support

[Wolfram Sang]

Identical to RZ/T2H except that interrupts are not wired.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
---
 Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml b/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml
index b426a34958d6..55e1a33c566b 100644
--- a/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml
+++ b/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml
@@ -23,6 +23,11 @@ properties:
           - const: renesas,r9a09g087-rtc  # RZ/N2H
           - const: renesas,r9a09g077-rtc  # RZ/T2H
 
+      - items:
+          - enum:
+              - renesas,r8a78000-rtc      # R-Car X5H
+          - const: renesas,rcar-gen5-rtc  # R-Car Gen5
+
   reg:
     maxItems: 1
 
@@ -66,6 +71,7 @@ allOf:
             enum:
               - renesas,r9a09g077-rtc
               - renesas,r9a09g087-rtc
+              - renesas,rcar-gen5-rtc
     then:
       properties:
         clocks:
-- 
2.53.0

[PATCH 6/6] rtc: rzn1: add R-Car X5H support

[Wolfram Sang]

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
---
 drivers/rtc/rtc-rzn1.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/rtc/rtc-rzn1.c b/drivers/rtc/rtc-rzn1.c
index ebb56c8d75ea..4360e125632e 100644
--- a/drivers/rtc/rtc-rzn1.c
+++ b/drivers/rtc/rtc-rzn1.c
@@ -526,6 +526,7 @@ static const struct rzn1_rtc_data rzn1_rtc_rzn1_data = {
 
 static const struct of_device_id rzn1_rtc_of_match[] = {
 	{ .compatible	= "renesas,r9a09g077-rtc", .data = &rzn1_rtc_rzt2h_data },
+	{ .compatible	= "renesas,rcar-gen5-rtc", .data = &rzn1_rtc_rzt2h_data },
 	{ .compatible	= "renesas,rzn1-rtc", .data = &rzn1_rtc_rzn1_data },
 	{ /* sentinel */ }
 };
-- 
2.53.0

Re: [PATCH 4/6] rtc: rzn1: make interrupts optional

[Wolfram Sang]

[-- Attachment #1: Type: text/plain, Size: 442 bytes --]

On Mon, Sep 14, 2026 at 11:18:29PM +0200, Wolfram Sang wrote:
> If no interrupts are specified, alarm handling will just be disabled. No
> need to bail out. Instead of juggling with 4 different static rtc_ops
> for all {subu|scmp}_{no_}alarm cases, a single non-static rtc_ops is
> chosen which is adapted during probe().

I kinda expected it. Sashiko complained enough abou the non-const
rtc_ops, so I will switch to multiple const ones...


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Re: [PATCH 1/6] dt-bindings: rtc: rzn1: drop unneeded 'start-year' from example

[Lad, Prabhakar]

On Mon, Sep 14, 2026 at 10:19 PM Wolfram Sang
<wsa+renesas@sang-engineering.com> wrote:
>
> We don't use 'start-year' in upstream DTs because the driver does the
> right thing by default, ranging from 2000 to 2099. So, drop it from the
> example, too.
>
> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
> ---
>  Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml | 1 -
>  1 file changed, 1 deletion(-)
>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

Cheers,
Prabhakar

> diff --git a/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml b/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml
> index ea7b039a91e7..e96007981c34 100644
> --- a/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml
> +++ b/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml
> @@ -91,5 +91,4 @@ examples:
>          clocks = <&sysctrl R9A06G032_HCLK_RTC>;
>          clock-names = "hclk";
>          power-domains = <&sysctrl>;
> -        start-year = <2000>;
>      };
> --
> 2.53.0
>
>

Re: [PATCH 2/6] dt-bindings: rtc: rzn1: add SoC names next to their IDs

[Lad, Prabhakar]

On Mon, Sep 14, 2026 at 10:19 PM Wolfram Sang
<wsa+renesas@sang-engineering.com> wrote:
>
> This helps maintaining because the numbers are easy to confuse.
>
> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
> ---
>  .../devicetree/bindings/rtc/renesas,rzn1-rtc.yaml      | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

Cheers,
Prabhakar

> diff --git a/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml b/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml
> index e96007981c34..7ea77cd0bee1 100644
> --- a/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml
> +++ b/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml
> @@ -14,14 +14,14 @@ properties:
>      oneOf:
>        - items:
>            - enum:
> -              - renesas,r9a06g032-rtc
> -          - const: renesas,rzn1-rtc
> +              - renesas,r9a06g032-rtc # RZ/N1D
> +          - const: renesas,rzn1-rtc   # RZ/N1
>
> -      - const: renesas,r9a09g077-rtc
> +      - const: renesas,r9a09g077-rtc  # RZ/T2H
>
>        - items:
> -          - const: renesas,r9a09g087-rtc
> -          - const: renesas,r9a09g077-rtc
> +          - const: renesas,r9a09g087-rtc  # RZ/N2H
> +          - const: renesas,r9a09g077-rtc  # RZ/T2H
>
>    reg:
>      maxItems: 1
> --
> 2.53.0
>
>

Re: [PATCH 3/6] dt-bindings: rtc: rzn1: interrupts are not required

[Lad, Prabhakar]

Hi Wolfram,

Thank you for the patch.

On Mon, Sep 14, 2026 at 10:24 PM Wolfram Sang
<wsa+renesas@sang-engineering.com> wrote:
>
> Interrupts are only needed for alarms to work. Reading/Setting the RTC
> works fine without interrupts. Drop the requirement for interrupts
> because an upcoming SoC does not have interrupts wired.
>
> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
> ---
>  Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml | 2 --
>  1 file changed, 2 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml b/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml
> index 7ea77cd0bee1..b426a34958d6 100644
> --- a/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml
> +++ b/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml
> @@ -52,8 +52,6 @@ properties:
>  required:
>    - compatible
>    - reg
> -  - interrupts
> -  - interrupt-names
Maybe we can add a conditional schema check for SoCs where
interrupts{-names} are required.

Cheers,
Prabhakar

>    - clocks
>    - clock-names
>    - power-domains
> --
> 2.53.0
>
>

Re: [PATCH 3/6] dt-bindings: rtc: rzn1: interrupts are not required

[Conor Dooley]

[-- Attachment #1: Type: text/plain, Size: 1486 bytes --]

On Tue, Sep 15, 2026 at 10:55:20AM +0100, Lad, Prabhakar wrote:
> Hi Wolfram,
> 
> Thank you for the patch.
> 
> On Mon, Sep 14, 2026 at 10:24 PM Wolfram Sang
> <wsa+renesas@sang-engineering.com> wrote:
> >
> > Interrupts are only needed for alarms to work. Reading/Setting the RTC
> > works fine without interrupts. Drop the requirement for interrupts
> > because an upcoming SoC does not have interrupts wired.
> >
> > Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
> > ---
> >  Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml | 2 --
> >  1 file changed, 2 deletions(-)
> >
> > diff --git a/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml b/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml
> > index 7ea77cd0bee1..b426a34958d6 100644
> > --- a/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml
> > +++ b/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml
> > @@ -52,8 +52,6 @@ properties:
> >  required:
> >    - compatible
> >    - reg
> > -  - interrupts
> > -  - interrupt-names
> Maybe we can add a conditional schema check for SoCs where
> interrupts{-names} are required.

Yeah, I'd prefer this. If all current devices have the interrupt wired,
there's little value in permitting them to not be populated and thereby
lose the support for alarms.

> 
> Cheers,
> Prabhakar
> 
> >    - clocks
> >    - clock-names
> >    - power-domains
> > --
> > 2.53.0
> >
> >

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Re: [PATCH 2/6] dt-bindings: rtc: rzn1: add SoC names next to their IDs

[Conor Dooley]

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Acked-by: Conor Dooley <conor.dooley@microchip.com>
pw-bot: not-applicable

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Re: [PATCH 1/6] dt-bindings: rtc: rzn1: drop unneeded 'start-year' from example

[Conor Dooley]

[-- Attachment #1: Type: text/plain, Size: 75 bytes --]

Acked-by: Conor Dooley <conor.dooley@microchip.com>
pw-bot: not-applicable

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Re: [PATCH 3/6] dt-bindings: rtc: rzn1: interrupts are not required

[Wolfram Sang]

[-- Attachment #1: Type: text/plain, Size: 370 bytes --]


> > Maybe we can add a conditional schema check for SoCs where
> > interrupts{-names} are required.
> 
> Yeah, I'd prefer this. If all current devices have the interrupt wired,
> there's little value in permitting them to not be populated and thereby
> lose the support for alarms.

Okay, I will refactor like this.

Thank you for your comments, everyone!


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