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 | 473 +++++++++++++++++++++++++++++++++++++++++++
3 files changed, 486 insertions(+)
diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index 2a95b05982ad..1d49738a2796 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -2043,4 +2043,16 @@ 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 3004e372f25f..2122f469e633 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..decd74df225c
--- /dev/null
+++ b/drivers/rtc/rtc-amlogic-a4.c
@@ -0,0 +1,473 @@
+// 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/module.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/bitfield.h>
+#include <linux/rtc.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/time64.h>
+#include <linux/delay.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);
+ }
+
+ 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 = 0;
+
+ /* 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, 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, ®_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, match_counter = 0, 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 aml_rtc_data *rtc;
+ void __iomem *base;
+ int ret = 0;
+
+ rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
+ if (!rtc)
+ return -ENOMEM;
+
+ rtc->config = of_device_get_match_data(&pdev->dev);
+ if (!rtc->config)
+ return -ENODEV;
+
+ base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(base))
+ return dev_err_probe(&pdev->dev, PTR_ERR(base), "resource ioremap failed\n");
+
+ rtc->map = devm_regmap_init_mmio(&pdev->dev, base, &aml_rtc_regmap_config);
+ if (IS_ERR(rtc->map))
+ return dev_err_probe(&pdev->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(&pdev->dev, "osc");
+ if (IS_ERR(rtc->rtc_clk))
+ return dev_err_probe(&pdev->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(&pdev->dev, -EINVAL, "Invalid clock configuration\n");
+
+ rtc->sys_clk = devm_clk_get(&pdev->dev, "sys");
+ if (IS_ERR(rtc->sys_clk))
+ return dev_err_probe(&pdev->dev, PTR_ERR(rtc->sys_clk),
+ "failed to get rtc sys clk\n");
+ ret = clk_prepare_enable(rtc->sys_clk);
+ if (ret)
+ return dev_err_probe(&pdev->dev, ret, "Failed to enable clk!\n");
+
+ aml_rtc_init(rtc);
+
+ device_init_wakeup(&pdev->dev, 1);
+ platform_set_drvdata(pdev, rtc);
+
+ rtc->rtc_dev = devm_rtc_allocate_device(&pdev->dev);
+ if (IS_ERR(rtc->rtc_dev)) {
+ ret = PTR_ERR(rtc->rtc_dev);
+ goto err_clk;
+ }
+
+ ret = devm_request_irq(&pdev->dev, rtc->irq, aml_rtc_handler,
+ IRQF_ONESHOT, "aml-rtc alarm", rtc);
+ if (ret) {
+ dev_err_probe(&pdev->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);
+
+ 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 int 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);
+
+ return 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");
--
2.37.1Le 01/11/2024 à 03:06, Xianwei Zhao via B4 Relay a écrit :
> From: Yiting Deng <yiting.deng-LpR1jeaWuhtBDgjK7y7TUQ@public.gmane.org>
>
> 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-LpR1jeaWuhtBDgjK7y7TUQ@public.gmane.org>
> Signed-off-by: Xianwei Zhao <xianwei.zhao-LpR1jeaWuhtBDgjK7y7TUQ@public.gmane.org>
...
> diff --git a/drivers/rtc/rtc-amlogic-a4.c b/drivers/rtc/rtc-amlogic-a4.c
> new file mode 100644
> index 000000000000..decd74df225c
> --- /dev/null
> +++ b/drivers/rtc/rtc-amlogic-a4.c
> @@ -0,0 +1,473 @@
> +// SPDX-License-Identifier: (GPL-2.0-only OR MIT)
> +/*
> + * Copyright (C) 2024 Amlogic, Inc. All rights reserved
> + * Author: Yiting Deng <yiting.deng-LpR1jeaWuhtBDgjK7y7TUQ@public.gmane.org>
> + */
> +
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +#include <linux/bitfield.h>
> +#include <linux/rtc.h>
> +#include <linux/clk.h>
> +#include <linux/clk-provider.h>
> +#include <linux/time64.h>
> +#include <linux/delay.h>
Nitpick: sometimes, alphabetical order is preferred.
> +
> +/* rtc oscillator rate */
> +#define OSC_32K (32768)
> +#define OSC_24M (24000000)
Nitpick: maybe these () could be removed to ease reading?
> +
> +#define RTC_CTRL (0x0 << 2) /* Control RTC */
> +#define RTC_ALRM0_EN BIT(0)
> +#define RTC_OSC_SEL BIT(8)
> +#define RTC_ENABLE BIT(12)
...
> +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);
Should we have something like:
if (!rtc->rtc_enabled) {
dev_err(dev, "<something>");
return -EINVAL;
}
if enabling fails?
> + }
> +
> + 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 = 0;
Nitpick: No need to init.
> +
> + /* 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_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, ®_val);
> + enable = FIELD_GET(RTC_ADJ_VALID, reg_val);
> + if (!enable) {
> + val = 0;
Nitpick: If val was initialised above, you could save 2 lines of code here.
> + } 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_probe(struct platform_device *pdev)
> +{
> + struct aml_rtc_data *rtc;
Nitpick: defining:
struct device *dev = &pdev->dev;
would simplify code bellow.
> + void __iomem *base;
> + int ret = 0;
> +
> + rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
> + if (!rtc)
> + return -ENOMEM;
> +
> + rtc->config = of_device_get_match_data(&pdev->dev);
> + if (!rtc->config)
> + return -ENODEV;
> +
> + base = devm_platform_ioremap_resource(pdev, 0);
> + if (IS_ERR(base))
> + return dev_err_probe(&pdev->dev, PTR_ERR(base), "resource ioremap failed\n");
> +
> + rtc->map = devm_regmap_init_mmio(&pdev->dev, base, &aml_rtc_regmap_config);
> + if (IS_ERR(rtc->map))
> + return dev_err_probe(&pdev->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(&pdev->dev, "osc");
> + if (IS_ERR(rtc->rtc_clk))
> + return dev_err_probe(&pdev->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(&pdev->dev, -EINVAL, "Invalid clock configuration\n");
> +
> + rtc->sys_clk = devm_clk_get(&pdev->dev, "sys");
Maybe devm_clk_get_enabled() to simplify code below and the .remove()
function?
> + if (IS_ERR(rtc->sys_clk))
> + return dev_err_probe(&pdev->dev, PTR_ERR(rtc->sys_clk),
> + "failed to get rtc sys clk\n");
> + ret = clk_prepare_enable(rtc->sys_clk);
> + if (ret)
> + return dev_err_probe(&pdev->dev, ret, "Failed to enable clk!\n");
> +
> + aml_rtc_init(rtc);
> +
> + device_init_wakeup(&pdev->dev, 1);
> + platform_set_drvdata(pdev, rtc);
> +
> + rtc->rtc_dev = devm_rtc_allocate_device(&pdev->dev);
> + if (IS_ERR(rtc->rtc_dev)) {
> + ret = PTR_ERR(rtc->rtc_dev);
> + goto err_clk;
> + }
> +
> + ret = devm_request_irq(&pdev->dev, rtc->irq, aml_rtc_handler,
> + IRQF_ONESHOT, "aml-rtc alarm", rtc);
> + if (ret) {
> + dev_err_probe(&pdev->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);
Should device_init_wakeup(..., 0) be called here?
(as in the remove function)
> +
> + return ret;
> +}
...
> +static SIMPLE_DEV_PM_OPS(aml_rtc_pm_ops,
> + aml_rtc_suspend, aml_rtc_resume);
> +
> +static int aml_rtc_remove(struct platform_device *pdev)
Should'nt it return void?
Compilation fails with latest -next.
> +{
> + 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);
> +
> + return 0;
> +}
...
CJ
Hi Christophe,
Thanks for your review. Most will take your advice.
On 2024/11/1 17:15, Christophe JAILLET wrote:
> [ EXTERNAL EMAIL ]
>
> Le 01/11/2024 à 03:06, Xianwei Zhao via B4 Relay a écrit :
>> From: Yiting Deng <yiting.deng-LpR1jeaWuhtBDgjK7y7TUQ@public.gmane.org>
>>
>> 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-LpR1jeaWuhtBDgjK7y7TUQ@public.gmane.org>
>> Signed-off-by: Xianwei Zhao
>> <xianwei.zhao-LpR1jeaWuhtBDgjK7y7TUQ@public.gmane.org>
>
> ...
>
>> diff --git a/drivers/rtc/rtc-amlogic-a4.c b/drivers/rtc/rtc-amlogic-a4.c
>> new file mode 100644
>> index 000000000000..decd74df225c
>> --- /dev/null
>> +++ b/drivers/rtc/rtc-amlogic-a4.c
>> @@ -0,0 +1,473 @@
>> +// SPDX-License-Identifier: (GPL-2.0-only OR MIT)
>> +/*
>> + * Copyright (C) 2024 Amlogic, Inc. All rights reserved
>> + * Author: Yiting Deng
>> <yiting.deng-LpR1jeaWuhtBDgjK7y7TUQ@public.gmane.org>
>> + */
>> +
>> +#include <linux/module.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/regmap.h>
>> +#include <linux/bitfield.h>
>> +#include <linux/rtc.h>
>> +#include <linux/clk.h>
>> +#include <linux/clk-provider.h>
>> +#include <linux/time64.h>
>> +#include <linux/delay.h>
>
> Nitpick: sometimes, alphabetical order is preferred.
>
>> +
>> +/* rtc oscillator rate */
>> +#define OSC_32K (32768)
>> +#define OSC_24M (24000000)
>
> Nitpick: maybe these () could be removed to ease reading?
>
>> +
>> +#define RTC_CTRL (0x0 << 2) /* Control RTC */
>> +#define RTC_ALRM0_EN BIT(0)
>> +#define RTC_OSC_SEL BIT(8)
>> +#define RTC_ENABLE BIT(12)
>
> ...
>
>> +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);
>
> Should we have something like:
>
> if (!rtc->rtc_enabled) {
> dev_err(dev, "<something>");
> return -EINVAL;
> }
>
> if enabling fails?
>
>> + }
>> +
>> + 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 = 0;
>
> Nitpick: No need to init.
>
>> +
>> + /* 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_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, ®_val);
>> + enable = FIELD_GET(RTC_ADJ_VALID, reg_val);
>> + if (!enable) {
>> + val = 0;
>
> Nitpick: If val was initialised above, you could save 2 lines of code here.
>
I'll leave it as it is, and seting value here is a better representation
of the meaning of the variable.
>> + } 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_probe(struct platform_device *pdev)
>> +{
>> + struct aml_rtc_data *rtc;
>
> Nitpick: defining:
> struct device *dev = &pdev->dev;
>
> would simplify code bellow.
>
>> + void __iomem *base;
>> + int ret = 0;
>> +
>> + rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
>> + if (!rtc)
>> + return -ENOMEM;
>> +
>> + rtc->config = of_device_get_match_data(&pdev->dev);
>> + if (!rtc->config)
>> + return -ENODEV;
>> +
>> + base = devm_platform_ioremap_resource(pdev, 0);
>> + if (IS_ERR(base))
>> + return dev_err_probe(&pdev->dev, PTR_ERR(base),
>> "resource ioremap failed\n");
>> +
>> + rtc->map = devm_regmap_init_mmio(&pdev->dev, base,
>> &aml_rtc_regmap_config);
>> + if (IS_ERR(rtc->map))
>> + return dev_err_probe(&pdev->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(&pdev->dev, "osc");
>> + if (IS_ERR(rtc->rtc_clk))
>> + return dev_err_probe(&pdev->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(&pdev->dev, -EINVAL, "Invalid clock
>> configuration\n");
>> +
>> + rtc->sys_clk = devm_clk_get(&pdev->dev, "sys");
>
> Maybe devm_clk_get_enabled() to simplify code below and the .remove()
> function?
>
>> + if (IS_ERR(rtc->sys_clk))
>> + return dev_err_probe(&pdev->dev, PTR_ERR(rtc->sys_clk),
>> + "failed to get rtc sys clk\n");
>> + ret = clk_prepare_enable(rtc->sys_clk);
>> + if (ret)
>> + return dev_err_probe(&pdev->dev, ret, "Failed to enable
>> clk!\n");
>> +
>> + aml_rtc_init(rtc);
>> +
>> + device_init_wakeup(&pdev->dev, 1);
>> + platform_set_drvdata(pdev, rtc);
>> +
>> + rtc->rtc_dev = devm_rtc_allocate_device(&pdev->dev);
>> + if (IS_ERR(rtc->rtc_dev)) {
>> + ret = PTR_ERR(rtc->rtc_dev);
>> + goto err_clk;
>> + }
>> +
>> + ret = devm_request_irq(&pdev->dev, rtc->irq, aml_rtc_handler,
>> + IRQF_ONESHOT, "aml-rtc alarm", rtc);
>> + if (ret) {
>> + dev_err_probe(&pdev->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);
>
> Should device_init_wakeup(..., 0) be called here?
> (as in the remove function)
>
>> +
>> + return ret;
>> +}
>
> ...
>
>> +static SIMPLE_DEV_PM_OPS(aml_rtc_pm_ops,
>> + aml_rtc_suspend, aml_rtc_resume);
>> +
>> +static int aml_rtc_remove(struct platform_device *pdev)
>
> Should'nt it return void?
> Compilation fails with latest -next.
>
>> +{
>> + 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);
>> +
>> + return 0;
>> +}
>
> ...
>
> CJ
>
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