[PATCH v5 0/3] support for amlogic rtc

[PATCH v5 0/3] support for amlogic rtc

[Xianwei Zhao via B4 Relay]

Add rtc driver and bindigns for the amlogic A4(A113L2) and A5(A113X2) SoCs.

Signed-off-by: Xianwei Zhao <xianwei.zhao@amlogic.com>
---
Changes in v5:
- Some formatting adjustments and minor fixes were made based on Christophe's suggestions.
- Link to v4: https://lore.kernel.org/r/20240920-rtc-v4-0-91ae5fb4e3d5@amlogic.com

Changes in v4:
- Keep the same order as as in properties.
- Link to v3: https://lore.kernel.org/r/20240910-rtc-v3-0-1fa077a69a20@amlogic.com

Changes in v3:
- Perfect the binding description and rename binding.
- Using dev_err_probe function correctly, and modify commit message.
- Change placement about MAINTAINERS.
- Link to v2: https://lore.kernel.org/r/20240903-rtc-v2-0-05da5755b8d9@amlogic.com

Changes in v2:
- Modify bindings clock name and perfect the example.
- Fix some bug in driver, and use dev_err_probe instead of dev_err in probe process.
- Use RTC API to handle calibration.
- Remove unused func and rename driver file name.
- Link to v1: https://lore.kernel.org/r/20240823-rtc-v1-0-6f70381da283@amlogic.com

---
Yiting Deng (3):
      dt-bindings: rtc: Add Amlogic A4 and A5 RTC
      rtc: support for the Amlogic on-chip RTC
      MAINTAINERS: Add an entry for Amlogic RTC driver

 .../devicetree/bindings/rtc/amlogic,a4-rtc.yaml    |  63 +++
 MAINTAINERS                                        |   8 +
 drivers/rtc/Kconfig                                |  12 +
 drivers/rtc/Makefile                               |   1 +
 drivers/rtc/rtc-amlogic-a4.c                       | 476 +++++++++++++++++++++
 5 files changed, 560 insertions(+)
---
base-commit: 8a2c49e0fd92e6760636bcfbf11e11d9ddd61cf9
change-id: 20240823-rtc-127cd8192a13

Best regards,
-- 
Xianwei Zhao <xianwei.zhao@amlogic.com>

[PATCH v5 1/3] dt-bindings: rtc: Add Amlogic A4 and A5 RTC

[Xianwei Zhao via B4 Relay]

From: Yiting Deng <yiting.deng@amlogic.com>

Add documentation describing the Amlogic A4(A113L2) and A5(A113X2) RTC.

Signed-off-by: Yiting Deng <yiting.deng@amlogic.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Xianwei Zhao <xianwei.zhao@amlogic.com>
---
 .../devicetree/bindings/rtc/amlogic,a4-rtc.yaml    | 63 ++++++++++++++++++++++
 1 file changed, 63 insertions(+)

diff --git a/Documentation/devicetree/bindings/rtc/amlogic,a4-rtc.yaml b/Documentation/devicetree/bindings/rtc/amlogic,a4-rtc.yaml
new file mode 100644
index 000000000000..5d3ac737abcb
--- /dev/null
+++ b/Documentation/devicetree/bindings/rtc/amlogic,a4-rtc.yaml
@@ -0,0 +1,63 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+# Copyright (C) 2024 Amlogic, Inc. All rights reserved
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/rtc/amlogic,a4-rtc.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Amlogic A4 and A5 RTC
+
+maintainers:
+  - Yiting Deng <yiting.deng@amlogic.com>
+  - Xianwei Zhao <xianwei.zhao@amlogic.com>
+
+allOf:
+  - $ref: rtc.yaml#
+
+properties:
+  compatible:
+    enum:
+      - amlogic,a4-rtc
+      - amlogic,a5-rtc
+
+  reg:
+    maxItems: 1
+
+  clocks:
+    items:
+      - description: RTC clock source, available 24M or 32K crystal
+          oscillator source. when using 24M, need to divide 24M into 32K.
+      - description: RTC module accesses the clock of the apb bus.
+
+  clock-names:
+    items:
+      - const: osc
+      - const: sys
+
+  interrupts:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - clocks
+  - clock-names
+  - interrupts
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+    apb {
+        #address-cells = <2>;
+        #size-cells = <2>;
+
+        rtc@8e600 {
+            compatible = "amlogic,a4-rtc";
+            reg = <0x0 0x8e600 0x0 0x38>;
+            clocks = <&xtal_32k>, <&clkc_periphs 1>;
+            clock-names = "osc", "sys";
+            interrupts = <GIC_SPI 131 IRQ_TYPE_EDGE_RISING>;
+        };
+    };

-- 
2.37.1

[PATCH v5 2/3] rtc: support for the Amlogic on-chip RTC

[Xianwei Zhao via B4 Relay]

From: Yiting Deng <yiting.deng@amlogic.com>

This is the third amlogic driver. The RTC hardware of A4 SoC is different
from the previous one. This RTC hardware includes a timing function and
an alarm function. But the existing has only timing function, alarm
function is using the system clock to implement a virtual alarm. Add
the RTC driver to support it.

Signed-off-by: Yiting Deng <yiting.deng@amlogic.com>
Signed-off-by: Xianwei Zhao <xianwei.zhao@amlogic.com>
---
 drivers/rtc/Kconfig          |  12 ++
 drivers/rtc/Makefile         |   1 +
 drivers/rtc/rtc-amlogic-a4.c | 476 +++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 489 insertions(+)

diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index 66eb1122248b..98bce0c42307 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -2070,4 +2070,16 @@ config RTC_DRV_SSD202D
 	  This driver can also be built as a module, if so, the module
 	  will be called "rtc-ssd20xd".
 
+config RTC_DRV_AMLOGIC_A4
+	tristate "Amlogic RTC"
+	depends on ARCH_MESON || COMPILE_TEST
+	select REGMAP_MMIO
+	default y
+	help
+	  If you say yes here you get support for the RTC block on the
+	  Amlogic A113L2(A4) and A113X2(A5) SoCs.
+
+	  This driver can also be built as a module. If so, the module
+	  will be called "rtc-amlogic-a4".
+
 endif # RTC_CLASS
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index f62340ecc534..efeba9a2eaad 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -26,6 +26,7 @@ obj-$(CONFIG_RTC_DRV_ABB5ZES3)	+= rtc-ab-b5ze-s3.o
 obj-$(CONFIG_RTC_DRV_ABEOZ9)	+= rtc-ab-eoz9.o
 obj-$(CONFIG_RTC_DRV_ABX80X)	+= rtc-abx80x.o
 obj-$(CONFIG_RTC_DRV_AC100)	+= rtc-ac100.o
+obj-$(CONFIG_RTC_DRV_AMLOGIC_A4)	+= rtc-amlogic-a4.o
 obj-$(CONFIG_RTC_DRV_ARMADA38X)	+= rtc-armada38x.o
 obj-$(CONFIG_RTC_DRV_AS3722)	+= rtc-as3722.o
 obj-$(CONFIG_RTC_DRV_ASM9260)	+= rtc-asm9260.o
diff --git a/drivers/rtc/rtc-amlogic-a4.c b/drivers/rtc/rtc-amlogic-a4.c
new file mode 100644
index 000000000000..6e3cce7c49be
--- /dev/null
+++ b/drivers/rtc/rtc-amlogic-a4.c
@@ -0,0 +1,476 @@
+// SPDX-License-Identifier: (GPL-2.0-only OR MIT)
+/*
+ * Copyright (C) 2024 Amlogic, Inc. All rights reserved
+ * Author: Yiting Deng <yiting.deng@amlogic.com>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/delay.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/rtc.h>
+#include <linux/time64.h>
+
+/* rtc oscillator rate */
+#define OSC_32K			32768
+#define OSC_24M			24000000
+
+#define RTC_CTRL		(0x0 << 2)		/* Control RTC */
+#define RTC_ALRM0_EN		BIT(0)
+#define RTC_OSC_SEL		BIT(8)
+#define RTC_ENABLE		BIT(12)
+
+#define RTC_COUNTER_REG		(0x1 << 2)		/* Program RTC counter initial value */
+
+#define RTC_ALARM0_REG		(0x2 << 2)		/* Program RTC alarm0 value */
+
+#define RTC_SEC_ADJUST_REG	(0x6 << 2)		/* Control second-based timing adjustment */
+#define RTC_MATCH_COUNTER	GENMASK(18, 0)
+#define RTC_SEC_ADJUST_CTRL	GENMASK(20, 19)
+#define RTC_ADJ_VALID		BIT(23)
+
+#define RTC_INT_MASK		(0x8 << 2)		/* RTC interrupt mask */
+#define RTC_ALRM0_IRQ_MSK	BIT(0)
+
+#define RTC_INT_CLR		(0x9 << 2)		/* Clear RTC interrupt */
+#define RTC_ALRM0_IRQ_CLR	BIT(0)
+
+#define RTC_OSCIN_CTRL0		(0xa << 2)		/* Control RTC clk from 24M */
+#define RTC_OSCIN_CTRL1		(0xb << 2)		/* Control RTC clk from 24M */
+#define RTC_OSCIN_IN_EN		BIT(31)
+#define RTC_OSCIN_OUT_CFG	GENMASK(29, 28)
+#define RTC_OSCIN_OUT_N0M0	GENMASK(11, 0)
+#define RTC_OSCIN_OUT_N1M1	GENMASK(23, 12)
+
+#define RTC_INT_STATUS		(0xc << 2)		/* RTC interrupt status */
+#define RTC_ALRM0_IRQ_STATUS	BIT(0)
+
+#define RTC_REAL_TIME		(0xd << 2)		/* RTC time value */
+
+#define RTC_OSCIN_OUT_32K_N0	0x2dc
+#define RTC_OSCIN_OUT_32K_N1	0x2db
+#define RTC_OSCIN_OUT_32K_M0	0x1
+#define RTC_OSCIN_OUT_32K_M1	0x2
+
+#define RTC_SWALLOW_SECOND	0x2
+#define RTC_INSERT_SECOND	0x3
+
+struct aml_rtc_config {
+	bool gray_stored;
+};
+
+struct aml_rtc_data {
+	struct regmap *map;
+	struct rtc_device *rtc_dev;
+	int irq;
+	struct clk *rtc_clk;
+	struct clk *sys_clk;
+	int rtc_enabled;
+	const struct aml_rtc_config *config;
+};
+
+static const struct regmap_config aml_rtc_regmap_config = {
+	.reg_bits = 32,
+	.val_bits = 32,
+	.reg_stride = 4,
+	.max_register = RTC_REAL_TIME,
+};
+
+static inline u32 gray_to_binary(u32 gray)
+{
+	u32 bcd = gray;
+	int size = sizeof(bcd) * 8;
+	int i;
+
+	for (i = 0; (1 << i) < size; i++)
+		bcd ^= bcd >> (1 << i);
+
+	return bcd;
+}
+
+static inline u32 binary_to_gray(u32 bcd)
+{
+	return bcd ^ (bcd >> 1);
+}
+
+static int aml_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+	struct aml_rtc_data *rtc = dev_get_drvdata(dev);
+	u32 time_sec;
+
+	/* if RTC disabled, read time failed */
+	if (!rtc->rtc_enabled) {
+		dev_err(dev, "RTC disabled, read time failed\n");
+		return -EINVAL;
+	}
+
+	regmap_read(rtc->map, RTC_REAL_TIME, &time_sec);
+	if (rtc->config->gray_stored)
+		time_sec = gray_to_binary(time_sec);
+	rtc_time64_to_tm(time_sec, tm);
+	dev_dbg(dev, "%s: read time = %us\n", __func__, time_sec);
+
+	return 0;
+}
+
+static int aml_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+	struct aml_rtc_data *rtc = dev_get_drvdata(dev);
+	u32 time_sec;
+
+	/* if RTC disabled, first enable it */
+	if (!rtc->rtc_enabled) {
+		regmap_write_bits(rtc->map, RTC_CTRL, RTC_ENABLE, RTC_ENABLE);
+		usleep_range(100, 200);
+		rtc->rtc_enabled = regmap_test_bits(rtc->map, RTC_CTRL, RTC_ENABLE);
+		if (!rtc->rtc_enabled) {
+			dev_err(dev, "RTC enable failed\n");
+			return -EINVAL;
+		}
+	}
+
+	time_sec = rtc_tm_to_time64(tm);
+	if (rtc->config->gray_stored)
+		time_sec = binary_to_gray(time_sec);
+	regmap_write(rtc->map, RTC_COUNTER_REG, time_sec);
+	dev_dbg(dev, "%s: set time = %us\n", __func__, time_sec);
+
+	return 0;
+}
+
+static int aml_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
+{
+	struct aml_rtc_data *rtc = dev_get_drvdata(dev);
+	time64_t alarm_sec;
+
+	/* if RTC disabled, set alarm failed */
+	if (!rtc->rtc_enabled) {
+		dev_err(dev, "RTC disabled, set alarm failed\n");
+		return -EINVAL;
+	}
+
+	regmap_update_bits(rtc->map, RTC_CTRL,
+			   RTC_ALRM0_EN, RTC_ALRM0_EN);
+	regmap_update_bits(rtc->map, RTC_INT_MASK,
+			   RTC_ALRM0_IRQ_MSK, 0);
+
+	alarm_sec = rtc_tm_to_time64(&alarm->time);
+	if (rtc->config->gray_stored)
+		alarm_sec = binary_to_gray(alarm_sec);
+	regmap_write(rtc->map, RTC_ALARM0_REG, alarm_sec);
+
+	dev_dbg(dev, "%s: alarm->enabled=%d alarm_set=%llds\n", __func__,
+		alarm->enabled, alarm_sec);
+
+	return 0;
+}
+
+static int aml_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
+{
+	struct aml_rtc_data *rtc = dev_get_drvdata(dev);
+	u32 alarm_sec;
+	int alarm_enable;
+	int alarm_mask;
+
+	/* if RTC disabled, read alarm failed */
+	if (!rtc->rtc_enabled) {
+		dev_err(dev, "RTC disabled, read alarm failed\n");
+		return -EINVAL;
+	}
+
+	regmap_read(rtc->map, RTC_ALARM0_REG, &alarm_sec);
+	if (rtc->config->gray_stored)
+		alarm_sec = gray_to_binary(alarm_sec);
+	rtc_time64_to_tm(alarm_sec, &alarm->time);
+
+	alarm_enable = regmap_test_bits(rtc->map, RTC_CTRL, RTC_ALRM0_EN);
+	alarm_mask = regmap_test_bits(rtc->map, RTC_INT_MASK, RTC_ALRM0_IRQ_MSK);
+	alarm->enabled = (alarm_enable && !alarm_mask) ? 1 : 0;
+	dev_dbg(dev, "%s: alarm->enabled=%d alarm=%us\n", __func__,
+		alarm->enabled, alarm_sec);
+
+	return 0;
+}
+
+static int aml_rtc_read_offset(struct device *dev, long *offset)
+{
+	struct aml_rtc_data *rtc = dev_get_drvdata(dev);
+	u32 reg_val;
+	long val;
+	int sign, match_counter, enable;
+
+	/* if RTC disabled, read offset failed */
+	if (!rtc->rtc_enabled) {
+		dev_err(dev, "RTC disabled, read offset failed\n");
+		return -EINVAL;
+	}
+
+	regmap_read(rtc->map, RTC_SEC_ADJUST_REG, &reg_val);
+	enable = FIELD_GET(RTC_ADJ_VALID, reg_val);
+	if (!enable) {
+		val = 0;
+	} else {
+		sign = FIELD_GET(RTC_SEC_ADJUST_CTRL, reg_val);
+		match_counter = FIELD_GET(RTC_MATCH_COUNTER, reg_val);
+		val = 1000000000 / (match_counter + 1);
+		if (sign == RTC_SWALLOW_SECOND)
+			val = -val;
+	}
+	*offset = val;
+
+	return 0;
+}
+
+static int aml_rtc_set_offset(struct device *dev, long offset)
+{
+	struct aml_rtc_data *rtc = dev_get_drvdata(dev);
+	int sign = 0;
+	int match_counter = 0;
+	int enable = 0;
+	u32 reg_val;
+
+	/* if RTC disabled, set offset failed */
+	if (!rtc->rtc_enabled) {
+		dev_err(dev, "RTC disabled, set offset failed\n");
+		return -EINVAL;
+	}
+
+	if (offset) {
+		enable = 1;
+		sign = offset < 0 ? RTC_SWALLOW_SECOND : RTC_INSERT_SECOND;
+		match_counter = 1000000000 / abs(offset) - 1;
+		if (match_counter < 0 || match_counter > RTC_MATCH_COUNTER)
+			return -EINVAL;
+	}
+
+	reg_val = FIELD_PREP(RTC_ADJ_VALID, enable) |
+		  FIELD_PREP(RTC_SEC_ADJUST_CTRL, sign) |
+		  FIELD_PREP(RTC_MATCH_COUNTER, match_counter);
+	regmap_write(rtc->map, RTC_SEC_ADJUST_REG, reg_val);
+
+	return 0;
+}
+
+static int aml_rtc_alarm_enable(struct device *dev, unsigned int enabled)
+{
+	struct aml_rtc_data *rtc = dev_get_drvdata(dev);
+
+	if (enabled) {
+		regmap_update_bits(rtc->map, RTC_CTRL,
+				   RTC_ALRM0_EN, RTC_ALRM0_EN);
+		regmap_update_bits(rtc->map, RTC_INT_MASK,
+				   RTC_ALRM0_IRQ_MSK, 0);
+	} else {
+		regmap_update_bits(rtc->map, RTC_INT_MASK,
+				   RTC_ALRM0_IRQ_MSK, RTC_ALRM0_IRQ_MSK);
+		regmap_update_bits(rtc->map, RTC_CTRL,
+				   RTC_ALRM0_EN, 0);
+	}
+
+	return 0;
+}
+
+static const struct rtc_class_ops aml_rtc_ops = {
+	.read_time = aml_rtc_read_time,
+	.set_time = aml_rtc_set_time,
+	.read_alarm = aml_rtc_read_alarm,
+	.set_alarm = aml_rtc_set_alarm,
+	.alarm_irq_enable = aml_rtc_alarm_enable,
+	.read_offset = aml_rtc_read_offset,
+	.set_offset = aml_rtc_set_offset,
+};
+
+static irqreturn_t aml_rtc_handler(int irq, void *data)
+{
+	struct aml_rtc_data *rtc = (struct aml_rtc_data *)data;
+
+	regmap_write(rtc->map, RTC_ALARM0_REG, 0);
+	regmap_write(rtc->map, RTC_INT_CLR, RTC_ALRM0_IRQ_STATUS);
+
+	rtc_update_irq(rtc->rtc_dev, 1, RTC_AF | RTC_IRQF);
+
+	return IRQ_HANDLED;
+}
+
+static void aml_rtc_init(struct aml_rtc_data *rtc)
+{
+	u32 reg_val = 0;
+
+	rtc->rtc_enabled = regmap_test_bits(rtc->map, RTC_CTRL, RTC_ENABLE);
+	if (!rtc->rtc_enabled) {
+		if (clk_get_rate(rtc->rtc_clk) == OSC_24M) {
+			/* select 24M oscillator */
+			regmap_write_bits(rtc->map, RTC_CTRL, RTC_OSC_SEL, RTC_OSC_SEL);
+
+			/*
+			 * Set RTC oscillator to freq_out to freq_in/((N0*M0+N1*M1)/(M0+M1))
+			 * Enable clock_in gate of oscillator 24MHz
+			 * Set N0 to 733, N1 to 732
+			 */
+			reg_val = FIELD_PREP(RTC_OSCIN_IN_EN, 1)
+				  | FIELD_PREP(RTC_OSCIN_OUT_CFG, 1)
+				  | FIELD_PREP(RTC_OSCIN_OUT_N0M0, RTC_OSCIN_OUT_32K_N0)
+				  | FIELD_PREP(RTC_OSCIN_OUT_N1M1, RTC_OSCIN_OUT_32K_N1);
+			regmap_write_bits(rtc->map, RTC_OSCIN_CTRL0, RTC_OSCIN_IN_EN
+					  | RTC_OSCIN_OUT_CFG | RTC_OSCIN_OUT_N0M0
+					  | RTC_OSCIN_OUT_N1M1, reg_val);
+
+			/* Set M0 to 2, M1 to 3, so freq_out = 32768 Hz*/
+			reg_val = FIELD_PREP(RTC_OSCIN_OUT_N0M0, RTC_OSCIN_OUT_32K_M0)
+				  | FIELD_PREP(RTC_OSCIN_OUT_N1M1, RTC_OSCIN_OUT_32K_M1);
+			regmap_write_bits(rtc->map, RTC_OSCIN_CTRL1, RTC_OSCIN_OUT_N0M0
+					  | RTC_OSCIN_OUT_N1M1, reg_val);
+		} else {
+			/* select 32K oscillator */
+			regmap_write_bits(rtc->map, RTC_CTRL, RTC_OSC_SEL, 0);
+		}
+	}
+	regmap_write_bits(rtc->map, RTC_INT_MASK,
+			  RTC_ALRM0_IRQ_MSK, RTC_ALRM0_IRQ_MSK);
+	regmap_write_bits(rtc->map, RTC_CTRL, RTC_ALRM0_EN, 0);
+}
+
+static int aml_rtc_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct aml_rtc_data *rtc;
+	void __iomem *base;
+	int ret = 0;
+
+	rtc = devm_kzalloc(dev, sizeof(*rtc), GFP_KERNEL);
+	if (!rtc)
+		return -ENOMEM;
+
+	rtc->config = of_device_get_match_data(dev);
+	if (!rtc->config)
+		return -ENODEV;
+
+	base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(base))
+		return dev_err_probe(dev, PTR_ERR(base), "resource ioremap failed\n");
+
+	rtc->map = devm_regmap_init_mmio(dev, base, &aml_rtc_regmap_config);
+	if (IS_ERR(rtc->map))
+		return dev_err_probe(dev, PTR_ERR(rtc->map), "regmap init failed\n");
+
+	rtc->irq = platform_get_irq(pdev, 0);
+	if (rtc->irq < 0)
+		return rtc->irq;
+
+	rtc->rtc_clk = devm_clk_get(dev, "osc");
+	if (IS_ERR(rtc->rtc_clk))
+		return dev_err_probe(dev, PTR_ERR(rtc->rtc_clk),
+				     "failed to find rtc clock\n");
+	if (clk_get_rate(rtc->rtc_clk) != OSC_32K && clk_get_rate(rtc->rtc_clk) != OSC_24M)
+		return dev_err_probe(dev, -EINVAL, "Invalid clock configuration\n");
+
+	rtc->sys_clk = devm_clk_get_enabled(dev, "sys");
+	if (IS_ERR(rtc->sys_clk))
+		return dev_err_probe(dev, PTR_ERR(rtc->sys_clk),
+				     "failed to get_enable rtc sys clk\n");
+	aml_rtc_init(rtc);
+
+	device_init_wakeup(dev, 1);
+	platform_set_drvdata(pdev, rtc);
+
+	rtc->rtc_dev = devm_rtc_allocate_device(dev);
+	if (IS_ERR(rtc->rtc_dev)) {
+		ret = PTR_ERR(rtc->rtc_dev);
+		goto err_clk;
+	}
+
+	ret = devm_request_irq(dev, rtc->irq, aml_rtc_handler,
+			       IRQF_ONESHOT, "aml-rtc alarm", rtc);
+	if (ret) {
+		dev_err_probe(dev, ret, "IRQ%d request failed, ret = %d\n",
+			      rtc->irq, ret);
+		goto err_clk;
+	}
+
+	rtc->rtc_dev->ops = &aml_rtc_ops;
+	rtc->rtc_dev->range_min = 0;
+	rtc->rtc_dev->range_max = U32_MAX;
+
+	ret = devm_rtc_register_device(rtc->rtc_dev);
+	if (ret) {
+		dev_err_probe(&pdev->dev, ret, "Failed to register RTC device: %d\n", ret);
+		goto err_clk;
+	}
+
+	return 0;
+err_clk:
+	clk_disable_unprepare(rtc->sys_clk);
+	device_init_wakeup(dev, 0);
+
+	return ret;
+}
+
+static int aml_rtc_suspend(struct device *dev)
+{
+	struct aml_rtc_data *rtc = dev_get_drvdata(dev);
+
+	if (device_may_wakeup(dev))
+		enable_irq_wake(rtc->irq);
+
+	return 0;
+}
+
+static int aml_rtc_resume(struct device *dev)
+{
+	struct aml_rtc_data *rtc = dev_get_drvdata(dev);
+
+	if (device_may_wakeup(dev))
+		disable_irq_wake(rtc->irq);
+
+	return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(aml_rtc_pm_ops,
+			 aml_rtc_suspend, aml_rtc_resume);
+
+static void aml_rtc_remove(struct platform_device *pdev)
+{
+	struct aml_rtc_data *rtc = dev_get_drvdata(&pdev->dev);
+
+	/* disable RTC */
+	regmap_write_bits(rtc->map, RTC_CTRL, RTC_ENABLE, 0);
+	clk_disable_unprepare(rtc->sys_clk);
+	device_init_wakeup(&pdev->dev, 0);
+}
+
+static const struct aml_rtc_config a5_rtc_config = {
+};
+
+static const struct aml_rtc_config a4_rtc_config = {
+	.gray_stored = true,
+};
+
+static const struct of_device_id aml_rtc_device_id[] = {
+	{
+		.compatible = "amlogic,a4-rtc",
+		.data = &a4_rtc_config,
+	},
+	{
+		.compatible = "amlogic,a5-rtc",
+		.data = &a5_rtc_config,
+	},
+};
+MODULE_DEVICE_TABLE(of, aml_rtc_device_id);
+
+static struct platform_driver aml_rtc_driver = {
+	.probe = aml_rtc_probe,
+	.remove = aml_rtc_remove,
+	.driver = {
+		.name = "aml-rtc",
+		.pm = &aml_rtc_pm_ops,
+		.of_match_table = aml_rtc_device_id,
+	},
+};
+
+module_platform_driver(aml_rtc_driver);
+MODULE_DESCRIPTION("Amlogic RTC driver");
+MODULE_AUTHOR("Yiting Deng <yiting.deng@amlogic.com>");
+MODULE_LICENSE("GPL");

-- 
2.37.1

Re: [PATCH v5 2/3] rtc: support for the Amlogic on-chip RTC

[Alexandre Belloni]

On 08/11/2024 13:54:42+0800, Xianwei Zhao via B4 Relay wrote:
> +static int aml_rtc_read_time(struct device *dev, struct rtc_time *tm)
> +{
> +	struct aml_rtc_data *rtc = dev_get_drvdata(dev);
> +	u32 time_sec;
> +
> +	/* if RTC disabled, read time failed */
> +	if (!rtc->rtc_enabled) {
> +		dev_err(dev, "RTC disabled, read time failed\n");

These messages should be dropped, they probably won't be seen by any
user.

> +		return -EINVAL;
> +	}
> +
> +	regmap_read(rtc->map, RTC_REAL_TIME, &time_sec);
> +	if (rtc->config->gray_stored)
> +		time_sec = gray_to_binary(time_sec);
> +	rtc_time64_to_tm(time_sec, tm);
> +	dev_dbg(dev, "%s: read time = %us\n", __func__, time_sec);
> +
> +	return 0;
> +}
> +
> +static int aml_rtc_set_time(struct device *dev, struct rtc_time *tm)
> +{
> +	struct aml_rtc_data *rtc = dev_get_drvdata(dev);
> +	u32 time_sec;
> +
> +	/* if RTC disabled, first enable it */
> +	if (!rtc->rtc_enabled) {
> +		regmap_write_bits(rtc->map, RTC_CTRL, RTC_ENABLE, RTC_ENABLE);
> +		usleep_range(100, 200);
> +		rtc->rtc_enabled = regmap_test_bits(rtc->map, RTC_CTRL, RTC_ENABLE);
> +		if (!rtc->rtc_enabled) {
> +			dev_err(dev, "RTC enable failed\n");
> +			return -EINVAL;
> +		}
> +	}
> +
> +	time_sec = rtc_tm_to_time64(tm);
> +	if (rtc->config->gray_stored)
> +		time_sec = binary_to_gray(time_sec);
> +	regmap_write(rtc->map, RTC_COUNTER_REG, time_sec);
> +	dev_dbg(dev, "%s: set time = %us\n", __func__, time_sec);
> +
> +	return 0;
> +}
> +
> +static int aml_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
> +{
> +	struct aml_rtc_data *rtc = dev_get_drvdata(dev);
> +	time64_t alarm_sec;
> +
> +	/* if RTC disabled, set alarm failed */
> +	if (!rtc->rtc_enabled) {
> +		dev_err(dev, "RTC disabled, set alarm failed\n");
> +		return -EINVAL;
> +	}
> +
> +	regmap_update_bits(rtc->map, RTC_CTRL,
> +			   RTC_ALRM0_EN, RTC_ALRM0_EN);
> +	regmap_update_bits(rtc->map, RTC_INT_MASK,
> +			   RTC_ALRM0_IRQ_MSK, 0);
> +
> +	alarm_sec = rtc_tm_to_time64(&alarm->time);
> +	if (rtc->config->gray_stored)
> +		alarm_sec = binary_to_gray(alarm_sec);
> +	regmap_write(rtc->map, RTC_ALARM0_REG, alarm_sec);
> +
> +	dev_dbg(dev, "%s: alarm->enabled=%d alarm_set=%llds\n", __func__,
> +		alarm->enabled, alarm_sec);
> +
> +	return 0;
> +}
> +
> +static int aml_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
> +{
> +	struct aml_rtc_data *rtc = dev_get_drvdata(dev);
> +	u32 alarm_sec;
> +	int alarm_enable;
> +	int alarm_mask;
> +
> +	/* if RTC disabled, read alarm failed */
> +	if (!rtc->rtc_enabled) {
> +		dev_err(dev, "RTC disabled, read alarm failed\n");
> +		return -EINVAL;
> +	}
> +
> +	regmap_read(rtc->map, RTC_ALARM0_REG, &alarm_sec);
> +	if (rtc->config->gray_stored)
> +		alarm_sec = gray_to_binary(alarm_sec);
> +	rtc_time64_to_tm(alarm_sec, &alarm->time);
> +
> +	alarm_enable = regmap_test_bits(rtc->map, RTC_CTRL, RTC_ALRM0_EN);
> +	alarm_mask = regmap_test_bits(rtc->map, RTC_INT_MASK, RTC_ALRM0_IRQ_MSK);
> +	alarm->enabled = (alarm_enable && !alarm_mask) ? 1 : 0;
> +	dev_dbg(dev, "%s: alarm->enabled=%d alarm=%us\n", __func__,
> +		alarm->enabled, alarm_sec);
> +
> +	return 0;
> +}
> +
> +static int aml_rtc_read_offset(struct device *dev, long *offset)
> +{
> +	struct aml_rtc_data *rtc = dev_get_drvdata(dev);
> +	u32 reg_val;
> +	long val;
> +	int sign, match_counter, enable;
> +
> +	/* if RTC disabled, read offset failed */
> +	if (!rtc->rtc_enabled) {
> +		dev_err(dev, "RTC disabled, read offset failed\n");
> +		return -EINVAL;
> +	}
> +
> +	regmap_read(rtc->map, RTC_SEC_ADJUST_REG, &reg_val);
> +	enable = FIELD_GET(RTC_ADJ_VALID, reg_val);
> +	if (!enable) {
> +		val = 0;
> +	} else {
> +		sign = FIELD_GET(RTC_SEC_ADJUST_CTRL, reg_val);
> +		match_counter = FIELD_GET(RTC_MATCH_COUNTER, reg_val);
> +		val = 1000000000 / (match_counter + 1);
> +		if (sign == RTC_SWALLOW_SECOND)
> +			val = -val;
> +	}
> +	*offset = val;
> +
> +	return 0;
> +}
> +
> +static int aml_rtc_set_offset(struct device *dev, long offset)
> +{
> +	struct aml_rtc_data *rtc = dev_get_drvdata(dev);
> +	int sign = 0;
> +	int match_counter = 0;
> +	int enable = 0;
> +	u32 reg_val;
> +
> +	/* if RTC disabled, set offset failed */
> +	if (!rtc->rtc_enabled) {
> +		dev_err(dev, "RTC disabled, set offset failed\n");
> +		return -EINVAL;
> +	}
> +
> +	if (offset) {
> +		enable = 1;
> +		sign = offset < 0 ? RTC_SWALLOW_SECOND : RTC_INSERT_SECOND;
> +		match_counter = 1000000000 / abs(offset) - 1;
> +		if (match_counter < 0 || match_counter > RTC_MATCH_COUNTER)
> +			return -EINVAL;
> +	}
> +
> +	reg_val = FIELD_PREP(RTC_ADJ_VALID, enable) |
> +		  FIELD_PREP(RTC_SEC_ADJUST_CTRL, sign) |
> +		  FIELD_PREP(RTC_MATCH_COUNTER, match_counter);
> +	regmap_write(rtc->map, RTC_SEC_ADJUST_REG, reg_val);
> +
> +	return 0;
> +}
> +
> +static int aml_rtc_alarm_enable(struct device *dev, unsigned int enabled)
> +{
> +	struct aml_rtc_data *rtc = dev_get_drvdata(dev);
> +
> +	if (enabled) {
> +		regmap_update_bits(rtc->map, RTC_CTRL,
> +				   RTC_ALRM0_EN, RTC_ALRM0_EN);
> +		regmap_update_bits(rtc->map, RTC_INT_MASK,
> +				   RTC_ALRM0_IRQ_MSK, 0);
> +	} else {
> +		regmap_update_bits(rtc->map, RTC_INT_MASK,
> +				   RTC_ALRM0_IRQ_MSK, RTC_ALRM0_IRQ_MSK);
> +		regmap_update_bits(rtc->map, RTC_CTRL,
> +				   RTC_ALRM0_EN, 0);
> +	}
> +
> +	return 0;
> +}
> +
> +static const struct rtc_class_ops aml_rtc_ops = {
> +	.read_time = aml_rtc_read_time,
> +	.set_time = aml_rtc_set_time,
> +	.read_alarm = aml_rtc_read_alarm,
> +	.set_alarm = aml_rtc_set_alarm,
> +	.alarm_irq_enable = aml_rtc_alarm_enable,
> +	.read_offset = aml_rtc_read_offset,
> +	.set_offset = aml_rtc_set_offset,
> +};
> +
> +static irqreturn_t aml_rtc_handler(int irq, void *data)
> +{
> +	struct aml_rtc_data *rtc = (struct aml_rtc_data *)data;
> +
> +	regmap_write(rtc->map, RTC_ALARM0_REG, 0);
> +	regmap_write(rtc->map, RTC_INT_CLR, RTC_ALRM0_IRQ_STATUS);
> +
> +	rtc_update_irq(rtc->rtc_dev, 1, RTC_AF | RTC_IRQF);
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static void aml_rtc_init(struct aml_rtc_data *rtc)
> +{
> +	u32 reg_val = 0;
> +
> +	rtc->rtc_enabled = regmap_test_bits(rtc->map, RTC_CTRL, RTC_ENABLE);
> +	if (!rtc->rtc_enabled) {
> +		if (clk_get_rate(rtc->rtc_clk) == OSC_24M) {
> +			/* select 24M oscillator */
> +			regmap_write_bits(rtc->map, RTC_CTRL, RTC_OSC_SEL, RTC_OSC_SEL);
> +
> +			/*
> +			 * Set RTC oscillator to freq_out to freq_in/((N0*M0+N1*M1)/(M0+M1))
> +			 * Enable clock_in gate of oscillator 24MHz
> +			 * Set N0 to 733, N1 to 732
> +			 */
> +			reg_val = FIELD_PREP(RTC_OSCIN_IN_EN, 1)
> +				  | FIELD_PREP(RTC_OSCIN_OUT_CFG, 1)
> +				  | FIELD_PREP(RTC_OSCIN_OUT_N0M0, RTC_OSCIN_OUT_32K_N0)
> +				  | FIELD_PREP(RTC_OSCIN_OUT_N1M1, RTC_OSCIN_OUT_32K_N1);
> +			regmap_write_bits(rtc->map, RTC_OSCIN_CTRL0, RTC_OSCIN_IN_EN
> +					  | RTC_OSCIN_OUT_CFG | RTC_OSCIN_OUT_N0M0
> +					  | RTC_OSCIN_OUT_N1M1, reg_val);
> +
> +			/* Set M0 to 2, M1 to 3, so freq_out = 32768 Hz*/
> +			reg_val = FIELD_PREP(RTC_OSCIN_OUT_N0M0, RTC_OSCIN_OUT_32K_M0)
> +				  | FIELD_PREP(RTC_OSCIN_OUT_N1M1, RTC_OSCIN_OUT_32K_M1);
> +			regmap_write_bits(rtc->map, RTC_OSCIN_CTRL1, RTC_OSCIN_OUT_N0M0
> +					  | RTC_OSCIN_OUT_N1M1, reg_val);
> +		} else {
> +			/* select 32K oscillator */
> +			regmap_write_bits(rtc->map, RTC_CTRL, RTC_OSC_SEL, 0);
> +		}
> +	}
> +	regmap_write_bits(rtc->map, RTC_INT_MASK,
> +			  RTC_ALRM0_IRQ_MSK, RTC_ALRM0_IRQ_MSK);
> +	regmap_write_bits(rtc->map, RTC_CTRL, RTC_ALRM0_EN, 0);
> +}
> +
> +static int aml_rtc_probe(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct aml_rtc_data *rtc;
> +	void __iomem *base;
> +	int ret = 0;
> +
> +	rtc = devm_kzalloc(dev, sizeof(*rtc), GFP_KERNEL);
> +	if (!rtc)
> +		return -ENOMEM;
> +
> +	rtc->config = of_device_get_match_data(dev);
> +	if (!rtc->config)
> +		return -ENODEV;
> +
> +	base = devm_platform_ioremap_resource(pdev, 0);
> +	if (IS_ERR(base))
> +		return dev_err_probe(dev, PTR_ERR(base), "resource ioremap failed\n");
> +
> +	rtc->map = devm_regmap_init_mmio(dev, base, &aml_rtc_regmap_config);
> +	if (IS_ERR(rtc->map))
> +		return dev_err_probe(dev, PTR_ERR(rtc->map), "regmap init failed\n");
> +
> +	rtc->irq = platform_get_irq(pdev, 0);
> +	if (rtc->irq < 0)
> +		return rtc->irq;
> +
> +	rtc->rtc_clk = devm_clk_get(dev, "osc");
> +	if (IS_ERR(rtc->rtc_clk))
> +		return dev_err_probe(dev, PTR_ERR(rtc->rtc_clk),
> +				     "failed to find rtc clock\n");
> +	if (clk_get_rate(rtc->rtc_clk) != OSC_32K && clk_get_rate(rtc->rtc_clk) != OSC_24M)
> +		return dev_err_probe(dev, -EINVAL, "Invalid clock configuration\n");
> +
> +	rtc->sys_clk = devm_clk_get_enabled(dev, "sys");
> +	if (IS_ERR(rtc->sys_clk))
> +		return dev_err_probe(dev, PTR_ERR(rtc->sys_clk),
> +				     "failed to get_enable rtc sys clk\n");
> +	aml_rtc_init(rtc);
> +
> +	device_init_wakeup(dev, 1);
> +	platform_set_drvdata(pdev, rtc);
> +
> +	rtc->rtc_dev = devm_rtc_allocate_device(dev);
> +	if (IS_ERR(rtc->rtc_dev)) {
> +		ret = PTR_ERR(rtc->rtc_dev);
> +		goto err_clk;
> +	}
> +
> +	ret = devm_request_irq(dev, rtc->irq, aml_rtc_handler,
> +			       IRQF_ONESHOT, "aml-rtc alarm", rtc);
> +	if (ret) {
> +		dev_err_probe(dev, ret, "IRQ%d request failed, ret = %d\n",
> +			      rtc->irq, ret);
> +		goto err_clk;
> +	}
> +
> +	rtc->rtc_dev->ops = &aml_rtc_ops;
> +	rtc->rtc_dev->range_min = 0;
> +	rtc->rtc_dev->range_max = U32_MAX;
> +
> +	ret = devm_rtc_register_device(rtc->rtc_dev);
> +	if (ret) {
> +		dev_err_probe(&pdev->dev, ret, "Failed to register RTC device: %d\n", ret);
> +		goto err_clk;
> +	}
> +
> +	return 0;
> +err_clk:
> +	clk_disable_unprepare(rtc->sys_clk);
> +	device_init_wakeup(dev, 0);
> +
> +	return ret;
> +}
> +
> +static int aml_rtc_suspend(struct device *dev)
> +{
> +	struct aml_rtc_data *rtc = dev_get_drvdata(dev);
> +
> +	if (device_may_wakeup(dev))
> +		enable_irq_wake(rtc->irq);
> +
> +	return 0;
> +}
> +
> +static int aml_rtc_resume(struct device *dev)
> +{
> +	struct aml_rtc_data *rtc = dev_get_drvdata(dev);
> +
> +	if (device_may_wakeup(dev))
> +		disable_irq_wake(rtc->irq);
> +
> +	return 0;
> +}

Building this, i got:

drivers/rtc/rtc-amlogic-a4.c:409:12: error: ‘aml_rtc_resume’ defined but not used [-Werror=unused-function]
  409 | static int aml_rtc_resume(struct device *dev)
      |            ^~~~~~~~~~~~~~
drivers/rtc/rtc-amlogic-a4.c:399:12: error: ‘aml_rtc_suspend’ defined but not used [-Werror=unused-function]
  399 | static int aml_rtc_suspend(struct device *dev)
      |            ^~~~~~~~~~~~~~~


> +
> +static SIMPLE_DEV_PM_OPS(aml_rtc_pm_ops,
> +			 aml_rtc_suspend, aml_rtc_resume);
> +
> +static void aml_rtc_remove(struct platform_device *pdev)
> +{
> +	struct aml_rtc_data *rtc = dev_get_drvdata(&pdev->dev);
> +
> +	/* disable RTC */
> +	regmap_write_bits(rtc->map, RTC_CTRL, RTC_ENABLE, 0);

You can't do this, this defeats the purpose of the RTC. Once started an
set, it must not be stopped.

> +	clk_disable_unprepare(rtc->sys_clk);
> +	device_init_wakeup(&pdev->dev, 0);
> +}
> +
> +static const struct aml_rtc_config a5_rtc_config = {
> +};
> +
> +static const struct aml_rtc_config a4_rtc_config = {
> +	.gray_stored = true,
> +};
> +
> +static const struct of_device_id aml_rtc_device_id[] = {
> +	{
> +		.compatible = "amlogic,a4-rtc",
> +		.data = &a4_rtc_config,
> +	},
> +	{
> +		.compatible = "amlogic,a5-rtc",
> +		.data = &a5_rtc_config,
> +	},
> +};
> +MODULE_DEVICE_TABLE(of, aml_rtc_device_id);
> +
> +static struct platform_driver aml_rtc_driver = {
> +	.probe = aml_rtc_probe,
> +	.remove = aml_rtc_remove,
> +	.driver = {
> +		.name = "aml-rtc",
> +		.pm = &aml_rtc_pm_ops,
> +		.of_match_table = aml_rtc_device_id,
> +	},
> +};
> +
> +module_platform_driver(aml_rtc_driver);
> +MODULE_DESCRIPTION("Amlogic RTC driver");
> +MODULE_AUTHOR("Yiting Deng <yiting.deng@amlogic.com>");
> +MODULE_LICENSE("GPL");
> 
> -- 
> 2.37.1
> 
> 

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

Re: [PATCH v5 2/3] rtc: support for the Amlogic on-chip RTC

[Xianwei Zhao]

Hi Alexandre,
      Thanks for your review.

On 2024/11/12 06:07, Alexandre Belloni wrote:
> [ EXTERNAL EMAIL ]
> 
> On 08/11/2024 13:54:42+0800, Xianwei Zhao via B4 Relay wrote:
>> +static int aml_rtc_read_time(struct device *dev, struct rtc_time *tm)
>> +{
>> +     struct aml_rtc_data *rtc = dev_get_drvdata(dev);
>> +     u32 time_sec;
>> +
>> +     /* if RTC disabled, read time failed */
>> +     if (!rtc->rtc_enabled) {
>> +             dev_err(dev, "RTC disabled, read time failed\n");
> 
> These messages should be dropped, they probably won't be seen by any
> user.

Will do.
> 
>> +             return -EINVAL;
>> +     }
>> +
>> +     regmap_read(rtc->map, RTC_REAL_TIME, &time_sec);
>> +     if (rtc->config->gray_stored)
>> +             time_sec = gray_to_binary(time_sec);
>> +     rtc_time64_to_tm(time_sec, tm);
>> +     dev_dbg(dev, "%s: read time = %us\n", __func__, time_sec);
>> +
>> +     return 0;
>> +}
>> +
>> +static int aml_rtc_set_time(struct device *dev, struct rtc_time *tm)
>> +{
>> +     struct aml_rtc_data *rtc = dev_get_drvdata(dev);
>> +     u32 time_sec;
>> +
>> +     /* if RTC disabled, first enable it */
>> +     if (!rtc->rtc_enabled) {
>> +             regmap_write_bits(rtc->map, RTC_CTRL, RTC_ENABLE, RTC_ENABLE);
>> +             usleep_range(100, 200);
>> +             rtc->rtc_enabled = regmap_test_bits(rtc->map, RTC_CTRL, RTC_ENABLE);
>> +             if (!rtc->rtc_enabled) {
>> +                     dev_err(dev, "RTC enable failed\n");
>> +                     return -EINVAL;
>> +             }
>> +     }
>> +
>> +     time_sec = rtc_tm_to_time64(tm);
>> +     if (rtc->config->gray_stored)
>> +             time_sec = binary_to_gray(time_sec);
>> +     regmap_write(rtc->map, RTC_COUNTER_REG, time_sec);
>> +     dev_dbg(dev, "%s: set time = %us\n", __func__, time_sec);
>> +
>> +     return 0;
>> +}
>> +
>> +static int aml_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
>> +{
>> +     struct aml_rtc_data *rtc = dev_get_drvdata(dev);
>> +     time64_t alarm_sec;
>> +
>> +     /* if RTC disabled, set alarm failed */
>> +     if (!rtc->rtc_enabled) {
>> +             dev_err(dev, "RTC disabled, set alarm failed\n");
>> +             return -EINVAL;
>> +     }
>> +
>> +     regmap_update_bits(rtc->map, RTC_CTRL,
>> +                        RTC_ALRM0_EN, RTC_ALRM0_EN);
>> +     regmap_update_bits(rtc->map, RTC_INT_MASK,
>> +                        RTC_ALRM0_IRQ_MSK, 0);
>> +
>> +     alarm_sec = rtc_tm_to_time64(&alarm->time);
>> +     if (rtc->config->gray_stored)
>> +             alarm_sec = binary_to_gray(alarm_sec);
>> +     regmap_write(rtc->map, RTC_ALARM0_REG, alarm_sec);
>> +
>> +     dev_dbg(dev, "%s: alarm->enabled=%d alarm_set=%llds\n", __func__,
>> +             alarm->enabled, alarm_sec);
>> +
>> +     return 0;
>> +}
>> +
>> +static int aml_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
>> +{
>> +     struct aml_rtc_data *rtc = dev_get_drvdata(dev);
>> +     u32 alarm_sec;
>> +     int alarm_enable;
>> +     int alarm_mask;
>> +
>> +     /* if RTC disabled, read alarm failed */
>> +     if (!rtc->rtc_enabled) {
>> +             dev_err(dev, "RTC disabled, read alarm failed\n");
>> +             return -EINVAL;
>> +     }
>> +
>> +     regmap_read(rtc->map, RTC_ALARM0_REG, &alarm_sec);
>> +     if (rtc->config->gray_stored)
>> +             alarm_sec = gray_to_binary(alarm_sec);
>> +     rtc_time64_to_tm(alarm_sec, &alarm->time);
>> +
>> +     alarm_enable = regmap_test_bits(rtc->map, RTC_CTRL, RTC_ALRM0_EN);
>> +     alarm_mask = regmap_test_bits(rtc->map, RTC_INT_MASK, RTC_ALRM0_IRQ_MSK);
>> +     alarm->enabled = (alarm_enable && !alarm_mask) ? 1 : 0;
>> +     dev_dbg(dev, "%s: alarm->enabled=%d alarm=%us\n", __func__,
>> +             alarm->enabled, alarm_sec);
>> +
>> +     return 0;
>> +}
>> +
>> +static int aml_rtc_read_offset(struct device *dev, long *offset)
>> +{
>> +     struct aml_rtc_data *rtc = dev_get_drvdata(dev);
>> +     u32 reg_val;
>> +     long val;
>> +     int sign, match_counter, enable;
>> +
>> +     /* if RTC disabled, read offset failed */
>> +     if (!rtc->rtc_enabled) {
>> +             dev_err(dev, "RTC disabled, read offset failed\n");
>> +             return -EINVAL;
>> +     }
>> +
>> +     regmap_read(rtc->map, RTC_SEC_ADJUST_REG, &reg_val);
>> +     enable = FIELD_GET(RTC_ADJ_VALID, reg_val);
>> +     if (!enable) {
>> +             val = 0;
>> +     } else {
>> +             sign = FIELD_GET(RTC_SEC_ADJUST_CTRL, reg_val);
>> +             match_counter = FIELD_GET(RTC_MATCH_COUNTER, reg_val);
>> +             val = 1000000000 / (match_counter + 1);
>> +             if (sign == RTC_SWALLOW_SECOND)
>> +                     val = -val;
>> +     }
>> +     *offset = val;
>> +
>> +     return 0;
>> +}
>> +
>> +static int aml_rtc_set_offset(struct device *dev, long offset)
>> +{
>> +     struct aml_rtc_data *rtc = dev_get_drvdata(dev);
>> +     int sign = 0;
>> +     int match_counter = 0;
>> +     int enable = 0;
>> +     u32 reg_val;
>> +
>> +     /* if RTC disabled, set offset failed */
>> +     if (!rtc->rtc_enabled) {
>> +             dev_err(dev, "RTC disabled, set offset failed\n");
>> +             return -EINVAL;
>> +     }
>> +
>> +     if (offset) {
>> +             enable = 1;
>> +             sign = offset < 0 ? RTC_SWALLOW_SECOND : RTC_INSERT_SECOND;
>> +             match_counter = 1000000000 / abs(offset) - 1;
>> +             if (match_counter < 0 || match_counter > RTC_MATCH_COUNTER)
>> +                     return -EINVAL;
>> +     }
>> +
>> +     reg_val = FIELD_PREP(RTC_ADJ_VALID, enable) |
>> +               FIELD_PREP(RTC_SEC_ADJUST_CTRL, sign) |
>> +               FIELD_PREP(RTC_MATCH_COUNTER, match_counter);
>> +     regmap_write(rtc->map, RTC_SEC_ADJUST_REG, reg_val);
>> +
>> +     return 0;
>> +}
>> +
>> +static int aml_rtc_alarm_enable(struct device *dev, unsigned int enabled)
>> +{
>> +     struct aml_rtc_data *rtc = dev_get_drvdata(dev);
>> +
>> +     if (enabled) {
>> +             regmap_update_bits(rtc->map, RTC_CTRL,
>> +                                RTC_ALRM0_EN, RTC_ALRM0_EN);
>> +             regmap_update_bits(rtc->map, RTC_INT_MASK,
>> +                                RTC_ALRM0_IRQ_MSK, 0);
>> +     } else {
>> +             regmap_update_bits(rtc->map, RTC_INT_MASK,
>> +                                RTC_ALRM0_IRQ_MSK, RTC_ALRM0_IRQ_MSK);
>> +             regmap_update_bits(rtc->map, RTC_CTRL,
>> +                                RTC_ALRM0_EN, 0);
>> +     }
>> +
>> +     return 0;
>> +}
>> +
>> +static const struct rtc_class_ops aml_rtc_ops = {
>> +     .read_time = aml_rtc_read_time,
>> +     .set_time = aml_rtc_set_time,
>> +     .read_alarm = aml_rtc_read_alarm,
>> +     .set_alarm = aml_rtc_set_alarm,
>> +     .alarm_irq_enable = aml_rtc_alarm_enable,
>> +     .read_offset = aml_rtc_read_offset,
>> +     .set_offset = aml_rtc_set_offset,
>> +};
>> +
>> +static irqreturn_t aml_rtc_handler(int irq, void *data)
>> +{
>> +     struct aml_rtc_data *rtc = (struct aml_rtc_data *)data;
>> +
>> +     regmap_write(rtc->map, RTC_ALARM0_REG, 0);
>> +     regmap_write(rtc->map, RTC_INT_CLR, RTC_ALRM0_IRQ_STATUS);
>> +
>> +     rtc_update_irq(rtc->rtc_dev, 1, RTC_AF | RTC_IRQF);
>> +
>> +     return IRQ_HANDLED;
>> +}
>> +
>> +static void aml_rtc_init(struct aml_rtc_data *rtc)
>> +{
>> +     u32 reg_val = 0;
>> +
>> +     rtc->rtc_enabled = regmap_test_bits(rtc->map, RTC_CTRL, RTC_ENABLE);
>> +     if (!rtc->rtc_enabled) {
>> +             if (clk_get_rate(rtc->rtc_clk) == OSC_24M) {
>> +                     /* select 24M oscillator */
>> +                     regmap_write_bits(rtc->map, RTC_CTRL, RTC_OSC_SEL, RTC_OSC_SEL);
>> +
>> +                     /*
>> +                      * Set RTC oscillator to freq_out to freq_in/((N0*M0+N1*M1)/(M0+M1))
>> +                      * Enable clock_in gate of oscillator 24MHz
>> +                      * Set N0 to 733, N1 to 732
>> +                      */
>> +                     reg_val = FIELD_PREP(RTC_OSCIN_IN_EN, 1)
>> +                               | FIELD_PREP(RTC_OSCIN_OUT_CFG, 1)
>> +                               | FIELD_PREP(RTC_OSCIN_OUT_N0M0, RTC_OSCIN_OUT_32K_N0)
>> +                               | FIELD_PREP(RTC_OSCIN_OUT_N1M1, RTC_OSCIN_OUT_32K_N1);
>> +                     regmap_write_bits(rtc->map, RTC_OSCIN_CTRL0, RTC_OSCIN_IN_EN
>> +                                       | RTC_OSCIN_OUT_CFG | RTC_OSCIN_OUT_N0M0
>> +                                       | RTC_OSCIN_OUT_N1M1, reg_val);
>> +
>> +                     /* Set M0 to 2, M1 to 3, so freq_out = 32768 Hz*/
>> +                     reg_val = FIELD_PREP(RTC_OSCIN_OUT_N0M0, RTC_OSCIN_OUT_32K_M0)
>> +                               | FIELD_PREP(RTC_OSCIN_OUT_N1M1, RTC_OSCIN_OUT_32K_M1);
>> +                     regmap_write_bits(rtc->map, RTC_OSCIN_CTRL1, RTC_OSCIN_OUT_N0M0
>> +                                       | RTC_OSCIN_OUT_N1M1, reg_val);
>> +             } else {
>> +                     /* select 32K oscillator */
>> +                     regmap_write_bits(rtc->map, RTC_CTRL, RTC_OSC_SEL, 0);
>> +             }
>> +     }
>> +     regmap_write_bits(rtc->map, RTC_INT_MASK,
>> +                       RTC_ALRM0_IRQ_MSK, RTC_ALRM0_IRQ_MSK);
>> +     regmap_write_bits(rtc->map, RTC_CTRL, RTC_ALRM0_EN, 0);
>> +}
>> +
>> +static int aml_rtc_probe(struct platform_device *pdev)
>> +{
>> +     struct device *dev = &pdev->dev;
>> +     struct aml_rtc_data *rtc;
>> +     void __iomem *base;
>> +     int ret = 0;
>> +
>> +     rtc = devm_kzalloc(dev, sizeof(*rtc), GFP_KERNEL);
>> +     if (!rtc)
>> +             return -ENOMEM;
>> +
>> +     rtc->config = of_device_get_match_data(dev);
>> +     if (!rtc->config)
>> +             return -ENODEV;
>> +
>> +     base = devm_platform_ioremap_resource(pdev, 0);
>> +     if (IS_ERR(base))
>> +             return dev_err_probe(dev, PTR_ERR(base), "resource ioremap failed\n");
>> +
>> +     rtc->map = devm_regmap_init_mmio(dev, base, &aml_rtc_regmap_config);
>> +     if (IS_ERR(rtc->map))
>> +             return dev_err_probe(dev, PTR_ERR(rtc->map), "regmap init failed\n");
>> +
>> +     rtc->irq = platform_get_irq(pdev, 0);
>> +     if (rtc->irq < 0)
>> +             return rtc->irq;
>> +
>> +     rtc->rtc_clk = devm_clk_get(dev, "osc");
>> +     if (IS_ERR(rtc->rtc_clk))
>> +             return dev_err_probe(dev, PTR_ERR(rtc->rtc_clk),
>> +                                  "failed to find rtc clock\n");
>> +     if (clk_get_rate(rtc->rtc_clk) != OSC_32K && clk_get_rate(rtc->rtc_clk) != OSC_24M)
>> +             return dev_err_probe(dev, -EINVAL, "Invalid clock configuration\n");
>> +
>> +     rtc->sys_clk = devm_clk_get_enabled(dev, "sys");
>> +     if (IS_ERR(rtc->sys_clk))
>> +             return dev_err_probe(dev, PTR_ERR(rtc->sys_clk),
>> +                                  "failed to get_enable rtc sys clk\n");
>> +     aml_rtc_init(rtc);
>> +
>> +     device_init_wakeup(dev, 1);
>> +     platform_set_drvdata(pdev, rtc);
>> +
>> +     rtc->rtc_dev = devm_rtc_allocate_device(dev);
>> +     if (IS_ERR(rtc->rtc_dev)) {
>> +             ret = PTR_ERR(rtc->rtc_dev);
>> +             goto err_clk;
>> +     }
>> +
>> +     ret = devm_request_irq(dev, rtc->irq, aml_rtc_handler,
>> +                            IRQF_ONESHOT, "aml-rtc alarm", rtc);
>> +     if (ret) {
>> +             dev_err_probe(dev, ret, "IRQ%d request failed, ret = %d\n",
>> +                           rtc->irq, ret);
>> +             goto err_clk;
>> +     }
>> +
>> +     rtc->rtc_dev->ops = &aml_rtc_ops;
>> +     rtc->rtc_dev->range_min = 0;
>> +     rtc->rtc_dev->range_max = U32_MAX;
>> +
>> +     ret = devm_rtc_register_device(rtc->rtc_dev);
>> +     if (ret) {
>> +             dev_err_probe(&pdev->dev, ret, "Failed to register RTC device: %d\n", ret);
>> +             goto err_clk;
>> +     }
>> +
>> +     return 0;
>> +err_clk:
>> +     clk_disable_unprepare(rtc->sys_clk);
>> +     device_init_wakeup(dev, 0);
>> +
>> +     return ret;
>> +}
>> +
>> +static int aml_rtc_suspend(struct device *dev)
>> +{
>> +     struct aml_rtc_data *rtc = dev_get_drvdata(dev);
>> +
>> +     if (device_may_wakeup(dev))
>> +             enable_irq_wake(rtc->irq);
>> +
>> +     return 0;
>> +}
>> +
>> +static int aml_rtc_resume(struct device *dev)
>> +{
>> +     struct aml_rtc_data *rtc = dev_get_drvdata(dev);
>> +
>> +     if (device_may_wakeup(dev))
>> +             disable_irq_wake(rtc->irq);
>> +
>> +     return 0;
>> +}
> 
> Building this, i got:
> 
> drivers/rtc/rtc-amlogic-a4.c:409:12: error: ‘aml_rtc_resume’ defined but not used [-Werror=unused-function]
>    409 | static int aml_rtc_resume(struct device *dev)
>        |            ^~~~~~~~~~~~~~
> drivers/rtc/rtc-amlogic-a4.c:399:12: error: ‘aml_rtc_suspend’ defined but not used [-Werror=unused-function]
>    399 | static int aml_rtc_suspend(struct device *dev)
>        |            ^~~~~~~~~~~~~~~
> 

Will fix it.

> 
>> +
>> +static SIMPLE_DEV_PM_OPS(aml_rtc_pm_ops,
>> +                      aml_rtc_suspend, aml_rtc_resume);
>> +
>> +static void aml_rtc_remove(struct platform_device *pdev)
>> +{
>> +     struct aml_rtc_data *rtc = dev_get_drvdata(&pdev->dev);
>> +
>> +     /* disable RTC */
>> +     regmap_write_bits(rtc->map, RTC_CTRL, RTC_ENABLE, 0);
> 
> You can't do this, this defeats the purpose of the RTC. Once started an
> set, it must not be stopped.
> 
OK, will dropped this action.

>> +     clk_disable_unprepare(rtc->sys_clk);
>> +     device_init_wakeup(&pdev->dev, 0);
>> +}
>> +
>> +static const struct aml_rtc_config a5_rtc_config = {
>> +};
>> +
>> +static const struct aml_rtc_config a4_rtc_config = {
>> +     .gray_stored = true,
>> +};
>> +
>> +static const struct of_device_id aml_rtc_device_id[] = {
>> +     {
>> +             .compatible = "amlogic,a4-rtc",
>> +             .data = &a4_rtc_config,
>> +     },
>> +     {
>> +             .compatible = "amlogic,a5-rtc",
>> +             .data = &a5_rtc_config,
>> +     },
>> +};
>> +MODULE_DEVICE_TABLE(of, aml_rtc_device_id);
>> +
>> +static struct platform_driver aml_rtc_driver = {
>> +     .probe = aml_rtc_probe,
>> +     .remove = aml_rtc_remove,
>> +     .driver = {
>> +             .name = "aml-rtc",
>> +             .pm = &aml_rtc_pm_ops,
>> +             .of_match_table = aml_rtc_device_id,
>> +     },
>> +};
>> +
>> +module_platform_driver(aml_rtc_driver);
>> +MODULE_DESCRIPTION("Amlogic RTC driver");
>> +MODULE_AUTHOR("Yiting Deng <yiting.deng@amlogic.com>");
>> +MODULE_LICENSE("GPL");
>>
>> --
>> 2.37.1
>>
>>
> 
> --
> Alexandre Belloni, co-owner and COO, Bootlin
> Embedded Linux and Kernel engineering
> https://bootlin.com

[PATCH v5 3/3] MAINTAINERS: Add an entry for Amlogic RTC driver

[Xianwei Zhao via B4 Relay]

From: Yiting Deng <yiting.deng@amlogic.com>

Add Amlogic RTC entry to MAINTAINERS to clarify the maintainers.

Signed-off-by: Yiting Deng <yiting.deng@amlogic.com>
Signed-off-by: Xianwei Zhao <xianwei.zhao@amlogic.com>
---
 MAINTAINERS | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index c27f3190737f..86675e03888c 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1209,6 +1209,14 @@ F:	Documentation/devicetree/bindings/perf/amlogic,g12-ddr-pmu.yaml
 F:	drivers/perf/amlogic/
 F:	include/soc/amlogic/
 
+AMLOGIC RTC DRIVER
+M:	Yiting Deng <yiting.deng@amlogic.com>
+M:	Xianwei Zhao <xianwei.zhao@amlogic.com>
+L:	linux-amlogic@lists.infradead.org
+S:	Maintained
+F:	Documentation/devicetree/bindings/rtc/amlogic,a4-rtc.yaml
+F:	drivers/rtc/rtc-amlogic-a4.c
+
 AMPHENOL CHIPCAP 2 HUMIDITY-TEMPERATURE IIO DRIVER
 M:	Javier Carrasco <javier.carrasco.cruz@gmail.com>
 L:	linux-hwmon@vger.kernel.org

-- 
2.37.1

Re: [PATCH v5 0/3] support for amlogic rtc

[Alexandre Belloni]

On Fri, 08 Nov 2024 13:54:40 +0800, Xianwei Zhao wrote:
> Add rtc driver and bindigns for the amlogic A4(A113L2) and A5(A113X2) SoCs.
> 
> 

Applied, thanks!

[1/3] dt-bindings: rtc: Add Amlogic A4 and A5 RTC
      https://git.kernel.org/abelloni/c/12defbf1429c
[2/3] rtc: support for the Amlogic on-chip RTC
      https://git.kernel.org/abelloni/c/db26c3d6eb01
[3/3] MAINTAINERS: Add an entry for Amlogic RTC driver
      https://git.kernel.org/abelloni/c/cf6f2ddfd039

Best regards,

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

Re: [PATCH v5 0/3] support for amlogic rtc

[Alexandre Belloni]

On 11/11/2024 22:47:51+0100, Alexandre Belloni wrote:
> On Fri, 08 Nov 2024 13:54:40 +0800, Xianwei Zhao wrote:
> > Add rtc driver and bindigns for the amlogic A4(A113L2) and A5(A113X2) SoCs.
> > 
> > 
> 
> Applied, thanks!

Actually, I dropped them, I'll comment on 2/3

> 
> [1/3] dt-bindings: rtc: Add Amlogic A4 and A5 RTC
>       https://git.kernel.org/abelloni/c/12defbf1429c
> [2/3] rtc: support for the Amlogic on-chip RTC
>       https://git.kernel.org/abelloni/c/db26c3d6eb01
> [3/3] MAINTAINERS: Add an entry for Amlogic RTC driver
>       https://git.kernel.org/abelloni/c/cf6f2ddfd039
> 
> Best regards,
> 
> -- 
> Alexandre Belloni, co-owner and COO, Bootlin
> Embedded Linux and Kernel engineering
> https://bootlin.com
> 

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