[PATCH 1/5] rtc: pm8xxx: implement no-alarm flag for non-HLOS owned alarm

[PATCH 1/5] rtc: pm8xxx: implement no-alarm flag for non-HLOS owned alarm

[Jonathan Marek]

Qualcomm x1e80100 firmware sets the ownership of the RTC alarm to ADSP.
Thus writing to RTC alarm registers and receiving alarm interrupts is not
possible.

Add a no-alarm flag to support RTC on this platform.

Signed-off-by: Jonathan Marek <jonathan@marek.ca>
---
 drivers/rtc/rtc-pm8xxx.c | 48 ++++++++++++++++++++++++++++------------
 1 file changed, 34 insertions(+), 14 deletions(-)

diff --git a/drivers/rtc/rtc-pm8xxx.c b/drivers/rtc/rtc-pm8xxx.c
index c32fba550c8e0..9240844022092 100644
--- a/drivers/rtc/rtc-pm8xxx.c
+++ b/drivers/rtc/rtc-pm8xxx.c
@@ -61,6 +61,7 @@ struct pm8xxx_rtc {
 	struct rtc_device *rtc;
 	struct regmap *regmap;
 	bool allow_set_time;
+	bool no_alarm;
 	int alarm_irq;
 	const struct pm8xxx_rtc_regs *regs;
 	struct device *dev;
@@ -375,6 +376,11 @@ static const struct rtc_class_ops pm8xxx_rtc_ops = {
 	.alarm_irq_enable = pm8xxx_rtc_alarm_irq_enable,
 };
 
+static const struct rtc_class_ops pm8xxx_rtc_no_alarm_ops = {
+	.read_time	= pm8xxx_rtc_read_time,
+	.set_time	= pm8xxx_rtc_set_time,
+};
+
 static irqreturn_t pm8xxx_alarm_trigger(int irq, void *dev_id)
 {
 	struct pm8xxx_rtc *rtc_dd = dev_id;
@@ -473,9 +479,13 @@ static int pm8xxx_rtc_probe(struct platform_device *pdev)
 	if (!rtc_dd->regmap)
 		return -ENXIO;
 
-	rtc_dd->alarm_irq = platform_get_irq(pdev, 0);
-	if (rtc_dd->alarm_irq < 0)
-		return -ENXIO;
+	rtc_dd->no_alarm = of_property_read_bool(pdev->dev.of_node, "no-alarm");
+
+	if (!rtc_dd->no_alarm) {
+		rtc_dd->alarm_irq = platform_get_irq(pdev, 0);
+		if (rtc_dd->alarm_irq < 0)
+			return -ENXIO;
+	}
 
 	rtc_dd->allow_set_time = of_property_read_bool(pdev->dev.of_node,
 						      "allow-set-time");
@@ -503,7 +513,8 @@ static int pm8xxx_rtc_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, rtc_dd);
 
-	device_init_wakeup(&pdev->dev, 1);
+	if (!rtc_dd->no_alarm)
+		device_init_wakeup(&pdev->dev, 1);
 
 	rtc_dd->rtc = devm_rtc_allocate_device(&pdev->dev);
 	if (IS_ERR(rtc_dd->rtc))
@@ -512,27 +523,36 @@ static int pm8xxx_rtc_probe(struct platform_device *pdev)
 	rtc_dd->rtc->ops = &pm8xxx_rtc_ops;
 	rtc_dd->rtc->range_max = U32_MAX;
 
-	rc = devm_request_any_context_irq(&pdev->dev, rtc_dd->alarm_irq,
-					  pm8xxx_alarm_trigger,
-					  IRQF_TRIGGER_RISING,
-					  "pm8xxx_rtc_alarm", rtc_dd);
-	if (rc < 0)
-		return rc;
+	if (!rtc_dd->no_alarm) {
+		rc = devm_request_any_context_irq(&pdev->dev, rtc_dd->alarm_irq,
+						  pm8xxx_alarm_trigger,
+						  IRQF_TRIGGER_RISING,
+						  "pm8xxx_rtc_alarm", rtc_dd);
+		if (rc < 0)
+			return rc;
+	} else {
+		rtc_dd->rtc->ops = &pm8xxx_rtc_no_alarm_ops;
+	}
 
 	rc = devm_rtc_register_device(rtc_dd->rtc);
 	if (rc)
 		return rc;
 
-	rc = dev_pm_set_wake_irq(&pdev->dev, rtc_dd->alarm_irq);
-	if (rc)
-		return rc;
+	if (!rtc_dd->no_alarm) {
+		rc = dev_pm_set_wake_irq(&pdev->dev, rtc_dd->alarm_irq);
+		if (rc)
+			return rc;
+	}
 
 	return 0;
 }
 
 static void pm8xxx_remove(struct platform_device *pdev)
 {
-	dev_pm_clear_wake_irq(&pdev->dev);
+	struct pm8xxx_rtc *rtc_dd = platform_get_drvdata(pdev);
+
+	if (!rtc_dd->no_alarm)
+		dev_pm_clear_wake_irq(&pdev->dev);
 }
 
 static struct platform_driver pm8xxx_rtc_driver = {
-- 
2.45.1

[PATCH 2/5] dt-bindings: rtc: qcom-pm8xxx: document no-alarm flag

[Jonathan Marek]

Qualcomm x1e80100 firmware sets the ownership of the RTC alarm to ADSP.
Thus writing to RTC alarm registers and receiving alarm interrupts is not
possible.

Add a no-alarm flag to support RTC on this platform.

Signed-off-by: Jonathan Marek <jonathan@marek.ca>
---
 Documentation/devicetree/bindings/rtc/qcom-pm8xxx-rtc.yaml | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/Documentation/devicetree/bindings/rtc/qcom-pm8xxx-rtc.yaml b/Documentation/devicetree/bindings/rtc/qcom-pm8xxx-rtc.yaml
index d274bb7a534b5..210f76a819e90 100644
--- a/Documentation/devicetree/bindings/rtc/qcom-pm8xxx-rtc.yaml
+++ b/Documentation/devicetree/bindings/rtc/qcom-pm8xxx-rtc.yaml
@@ -40,6 +40,11 @@ properties:
     description:
       Indicates that the setting of RTC time is allowed by the host CPU.
 
+  no-alarm:
+    $ref: /schemas/types.yaml#/definitions/flag
+    description:
+      Indicates that RTC alarm is not owned by HLOS (Linux).
+
   nvmem-cells:
     items:
       - description:
-- 
2.45.1

[PATCH 3/5] arm64: dts: qcom: x1e80100-pmics: enable RTC

[Jonathan Marek]

Only access to RTC alarm is blocked.

Enable RTC access by setting the no-alarm flag.

Signed-off-by: Jonathan Marek <jonathan@marek.ca>
---
 arch/arm64/boot/dts/qcom/x1e80100-pmics.dtsi | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/arch/arm64/boot/dts/qcom/x1e80100-pmics.dtsi b/arch/arm64/boot/dts/qcom/x1e80100-pmics.dtsi
index 5b54ee79f048e..304a98d60472e 100644
--- a/arch/arm64/boot/dts/qcom/x1e80100-pmics.dtsi
+++ b/arch/arm64/boot/dts/qcom/x1e80100-pmics.dtsi
@@ -220,11 +220,9 @@ pon_resin: resin {
 
 		pmk8550_rtc: rtc@6100 {
 			compatible = "qcom,pmk8350-rtc";
-			reg = <0x6100>, <0x6200>;
-			reg-names = "rtc", "alarm";
-			interrupts = <0x0 0x62 0x1 IRQ_TYPE_EDGE_RISING>;
-			/* Not yet sure what blocks access */
-			status = "reserved";
+			reg = <0x6100>;
+			reg-names = "rtc";
+			no-alarm; /* alarm owned by ADSP */
 		};
 
 		pmk8550_sdam_2: nvram@7100 {
-- 
2.45.1

[PATCH 4/5] arm64: dts: qcom: x1e80100-crd: add rtc offset to set rtc time

[Jonathan Marek]

See commit e67b45582c5e for explanation.

Note: the 0xbc offset is arbitrary, it just needs to not be already in use.

Signed-off-by: Jonathan Marek <jonathan@marek.ca>
---
 arch/arm64/boot/dts/qcom/x1e80100-crd.dts | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/arch/arm64/boot/dts/qcom/x1e80100-crd.dts b/arch/arm64/boot/dts/qcom/x1e80100-crd.dts
index 53e76b3f0c831..c8fac0f2701b9 100644
--- a/arch/arm64/boot/dts/qcom/x1e80100-crd.dts
+++ b/arch/arm64/boot/dts/qcom/x1e80100-crd.dts
@@ -1224,6 +1224,17 @@ edp_bl_en: edp-bl-en-state {
 	};
 };
 
+&pmk8550_rtc {
+	nvmem-cells = <&rtc_offset>;
+	nvmem-cell-names = "offset";
+};
+
+&pmk8550_sdam_2 {
+	rtc_offset: rtc-offset@bc {
+		reg = <0xbc 0x4>;
+	};
+};
+
 &qupv3_0 {
 	status = "okay";
 };
-- 
2.45.1

[PATCH 5/5] arm64: dts: qcom: x1e78100-t14s: add rtc offset to set rtc time

[Jonathan Marek]

See commit e67b45582c5e for explanation.

Note: the 0xbc offset is arbitrary, it just needs to not be already in use.

Signed-off-by: Jonathan Marek <jonathan@marek.ca>
---
 .../boot/dts/qcom/x1e78100-lenovo-thinkpad-t14s.dts   | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/arch/arm64/boot/dts/qcom/x1e78100-lenovo-thinkpad-t14s.dts b/arch/arm64/boot/dts/qcom/x1e78100-lenovo-thinkpad-t14s.dts
index 8cd08c3a93382..f406c3a63d6a1 100644
--- a/arch/arm64/boot/dts/qcom/x1e78100-lenovo-thinkpad-t14s.dts
+++ b/arch/arm64/boot/dts/qcom/x1e78100-lenovo-thinkpad-t14s.dts
@@ -897,6 +897,17 @@ edp_bl_en: edp-bl-en-state {
 	};
 };
 
+&pmk8550_rtc {
+	nvmem-cells = <&rtc_offset>;
+	nvmem-cell-names = "offset";
+};
+
+&pmk8550_sdam_2 {
+	rtc_offset: rtc-offset@bc {
+		reg = <0xbc 0x4>;
+	};
+};
+
 &qupv3_0 {
 	status = "okay";
 };
-- 
2.45.1

Re: [PATCH 1/5] rtc: pm8xxx: implement no-alarm flag for non-HLOS owned alarm

[Alexandre Belloni]

On 11/10/2024 11:22:39-0400, Jonathan Marek wrote:
> Qualcomm x1e80100 firmware sets the ownership of the RTC alarm to ADSP.
> Thus writing to RTC alarm registers and receiving alarm interrupts is not
> possible.
> 
> Add a no-alarm flag to support RTC on this platform.
> 
> Signed-off-by: Jonathan Marek <jonathan@marek.ca>
> ---
>  drivers/rtc/rtc-pm8xxx.c | 48 ++++++++++++++++++++++++++++------------
>  1 file changed, 34 insertions(+), 14 deletions(-)
> 
> diff --git a/drivers/rtc/rtc-pm8xxx.c b/drivers/rtc/rtc-pm8xxx.c
> index c32fba550c8e0..9240844022092 100644
> --- a/drivers/rtc/rtc-pm8xxx.c
> +++ b/drivers/rtc/rtc-pm8xxx.c
> @@ -61,6 +61,7 @@ struct pm8xxx_rtc {
>  	struct rtc_device *rtc;
>  	struct regmap *regmap;
>  	bool allow_set_time;
> +	bool no_alarm;
>  	int alarm_irq;
>  	const struct pm8xxx_rtc_regs *regs;
>  	struct device *dev;
> @@ -375,6 +376,11 @@ static const struct rtc_class_ops pm8xxx_rtc_ops = {
>  	.alarm_irq_enable = pm8xxx_rtc_alarm_irq_enable,
>  };
>  
> +static const struct rtc_class_ops pm8xxx_rtc_no_alarm_ops = {
> +	.read_time	= pm8xxx_rtc_read_time,
> +	.set_time	= pm8xxx_rtc_set_time,
> +};
> +

Please clear the alarm feature flag instead of duplicating the ops

>  static irqreturn_t pm8xxx_alarm_trigger(int irq, void *dev_id)
>  {
>  	struct pm8xxx_rtc *rtc_dd = dev_id;
> @@ -473,9 +479,13 @@ static int pm8xxx_rtc_probe(struct platform_device *pdev)
>  	if (!rtc_dd->regmap)
>  		return -ENXIO;
>  
> -	rtc_dd->alarm_irq = platform_get_irq(pdev, 0);
> -	if (rtc_dd->alarm_irq < 0)
> -		return -ENXIO;
> +	rtc_dd->no_alarm = of_property_read_bool(pdev->dev.of_node, "no-alarm");
> +
> +	if (!rtc_dd->no_alarm) {
> +		rtc_dd->alarm_irq = platform_get_irq(pdev, 0);
> +		if (rtc_dd->alarm_irq < 0)
> +			return -ENXIO;
> +	}
>  
>  	rtc_dd->allow_set_time = of_property_read_bool(pdev->dev.of_node,
>  						      "allow-set-time");
> @@ -503,7 +513,8 @@ static int pm8xxx_rtc_probe(struct platform_device *pdev)
>  
>  	platform_set_drvdata(pdev, rtc_dd);
>  
> -	device_init_wakeup(&pdev->dev, 1);
> +	if (!rtc_dd->no_alarm)
> +		device_init_wakeup(&pdev->dev, 1);
>  
>  	rtc_dd->rtc = devm_rtc_allocate_device(&pdev->dev);
>  	if (IS_ERR(rtc_dd->rtc))
> @@ -512,27 +523,36 @@ static int pm8xxx_rtc_probe(struct platform_device *pdev)
>  	rtc_dd->rtc->ops = &pm8xxx_rtc_ops;
>  	rtc_dd->rtc->range_max = U32_MAX;
>  
> -	rc = devm_request_any_context_irq(&pdev->dev, rtc_dd->alarm_irq,
> -					  pm8xxx_alarm_trigger,
> -					  IRQF_TRIGGER_RISING,
> -					  "pm8xxx_rtc_alarm", rtc_dd);
> -	if (rc < 0)
> -		return rc;
> +	if (!rtc_dd->no_alarm) {
> +		rc = devm_request_any_context_irq(&pdev->dev, rtc_dd->alarm_irq,
> +						  pm8xxx_alarm_trigger,
> +						  IRQF_TRIGGER_RISING,
> +						  "pm8xxx_rtc_alarm", rtc_dd);
> +		if (rc < 0)
> +			return rc;
> +	} else {
> +		rtc_dd->rtc->ops = &pm8xxx_rtc_no_alarm_ops;
> +	}
>  
>  	rc = devm_rtc_register_device(rtc_dd->rtc);
>  	if (rc)
>  		return rc;
>  
> -	rc = dev_pm_set_wake_irq(&pdev->dev, rtc_dd->alarm_irq);
> -	if (rc)
> -		return rc;
> +	if (!rtc_dd->no_alarm) {
> +		rc = dev_pm_set_wake_irq(&pdev->dev, rtc_dd->alarm_irq);
> +		if (rc)
> +			return rc;
> +	}
>  
>  	return 0;
>  }
>  
>  static void pm8xxx_remove(struct platform_device *pdev)
>  {
> -	dev_pm_clear_wake_irq(&pdev->dev);
> +	struct pm8xxx_rtc *rtc_dd = platform_get_drvdata(pdev);
> +
> +	if (!rtc_dd->no_alarm)
> +		dev_pm_clear_wake_irq(&pdev->dev);
>  }
>  
>  static struct platform_driver pm8xxx_rtc_driver = {
> -- 
> 2.45.1
> 

-- 
Alexandre Belloni, co-owner and COO, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com