diff options
Diffstat (limited to 'drivers/rtc/rtc-cv1800.c')
| -rw-r--r-- | drivers/rtc/rtc-cv1800.c | 218 |
1 files changed, 218 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-cv1800.c b/drivers/rtc/rtc-cv1800.c new file mode 100644 index 000000000000..678c2c10bf58 --- /dev/null +++ b/drivers/rtc/rtc-cv1800.c @@ -0,0 +1,218 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * rtc-cv1800.c: RTC driver for Sophgo cv1800 RTC + * + * Author: Jingbao Qiu <qiujingbao.dlmu@gmail.com> + */ + +#include <linux/clk.h> +#include <linux/irq.h> +#include <linux/kernel.h> +#include <linux/mfd/syscon.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> +#include <linux/rtc.h> + +#define SEC_PULSE_GEN 0x1004 +#define ALARM_TIME 0x1008 +#define ALARM_ENABLE 0x100C +#define SET_SEC_CNTR_VAL 0x1010 +#define SET_SEC_CNTR_TRIG 0x1014 +#define SEC_CNTR_VAL 0x1018 + +/* + * When in VDDBKUP domain, this MACRO register + * does not power down + */ +#define MACRO_RO_T 0x14A8 +#define MACRO_RG_SET_T 0x1498 + +#define ALARM_ENABLE_MASK BIT(0) +#define SEL_SEC_PULSE BIT(31) + +struct cv1800_rtc_priv { + struct rtc_device *rtc_dev; + struct regmap *rtc_map; + struct clk *clk; + int irq; +}; + +static bool cv1800_rtc_enabled(struct device *dev) +{ + struct cv1800_rtc_priv *info = dev_get_drvdata(dev); + u32 reg; + + regmap_read(info->rtc_map, SEC_PULSE_GEN, ®); + + return (reg & SEL_SEC_PULSE) == 0; +} + +static void cv1800_rtc_enable(struct device *dev) +{ + struct cv1800_rtc_priv *info = dev_get_drvdata(dev); + + /* Sec pulse generated internally */ + regmap_update_bits(info->rtc_map, SEC_PULSE_GEN, SEL_SEC_PULSE, 0); +} + +static int cv1800_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) +{ + struct cv1800_rtc_priv *info = dev_get_drvdata(dev); + + regmap_write(info->rtc_map, ALARM_ENABLE, enabled); + + return 0; +} + +static int cv1800_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + struct cv1800_rtc_priv *info = dev_get_drvdata(dev); + unsigned long alarm_time; + + alarm_time = rtc_tm_to_time64(&alrm->time); + + cv1800_rtc_alarm_irq_enable(dev, 0); + + regmap_write(info->rtc_map, ALARM_TIME, alarm_time); + + cv1800_rtc_alarm_irq_enable(dev, alrm->enabled); + + return 0; +} + +static int cv1800_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm) +{ + struct cv1800_rtc_priv *info = dev_get_drvdata(dev); + u32 enabled; + u32 time; + + if (!cv1800_rtc_enabled(dev)) { + alarm->enabled = 0; + return 0; + } + + regmap_read(info->rtc_map, ALARM_ENABLE, &enabled); + + alarm->enabled = enabled & ALARM_ENABLE_MASK; + + regmap_read(info->rtc_map, ALARM_TIME, &time); + + rtc_time64_to_tm(time, &alarm->time); + + return 0; +} + +static int cv1800_rtc_read_time(struct device *dev, struct rtc_time *tm) +{ + struct cv1800_rtc_priv *info = dev_get_drvdata(dev); + u32 sec; + + if (!cv1800_rtc_enabled(dev)) + return -EINVAL; + + regmap_read(info->rtc_map, SEC_CNTR_VAL, &sec); + + rtc_time64_to_tm(sec, tm); + + return 0; +} + +static int cv1800_rtc_set_time(struct device *dev, struct rtc_time *tm) +{ + struct cv1800_rtc_priv *info = dev_get_drvdata(dev); + unsigned long sec; + + sec = rtc_tm_to_time64(tm); + + regmap_write(info->rtc_map, SET_SEC_CNTR_VAL, sec); + regmap_write(info->rtc_map, SET_SEC_CNTR_TRIG, 1); + + regmap_write(info->rtc_map, MACRO_RG_SET_T, sec); + + cv1800_rtc_enable(dev); + + return 0; +} + +static irqreturn_t cv1800_rtc_irq_handler(int irq, void *dev_id) +{ + struct cv1800_rtc_priv *info = dev_id; + + rtc_update_irq(info->rtc_dev, 1, RTC_IRQF | RTC_AF); + + regmap_write(info->rtc_map, ALARM_ENABLE, 0); + + return IRQ_HANDLED; +} + +static const struct rtc_class_ops cv1800_rtc_ops = { + .read_time = cv1800_rtc_read_time, + .set_time = cv1800_rtc_set_time, + .read_alarm = cv1800_rtc_read_alarm, + .set_alarm = cv1800_rtc_set_alarm, + .alarm_irq_enable = cv1800_rtc_alarm_irq_enable, +}; + +static int cv1800_rtc_probe(struct platform_device *pdev) +{ + struct cv1800_rtc_priv *rtc; + int ret; + + rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL); + if (!rtc) + return -ENOMEM; + + rtc->rtc_map = device_node_to_regmap(pdev->dev.parent->of_node); + if (IS_ERR(rtc->rtc_map)) + return dev_err_probe(&pdev->dev, PTR_ERR(rtc->rtc_map), + "cannot get parent regmap\n"); + + rtc->irq = platform_get_irq(pdev, 0); + if (rtc->irq < 0) + return rtc->irq; + + rtc->clk = devm_clk_get_enabled(pdev->dev.parent, "rtc"); + if (IS_ERR(rtc->clk)) + return dev_err_probe(&pdev->dev, PTR_ERR(rtc->clk), + "rtc clk not found\n"); + + platform_set_drvdata(pdev, rtc); + + device_init_wakeup(&pdev->dev, 1); + + rtc->rtc_dev = devm_rtc_allocate_device(&pdev->dev); + if (IS_ERR(rtc->rtc_dev)) + return PTR_ERR(rtc->rtc_dev); + + rtc->rtc_dev->ops = &cv1800_rtc_ops; + rtc->rtc_dev->range_max = U32_MAX; + + ret = devm_request_irq(&pdev->dev, rtc->irq, cv1800_rtc_irq_handler, + IRQF_TRIGGER_HIGH, "rtc alarm", rtc); + if (ret) + return dev_err_probe(&pdev->dev, ret, + "cannot register interrupt handler\n"); + + return devm_rtc_register_device(rtc->rtc_dev); +} + +static const struct platform_device_id cv1800_rtc_id[] = { + { .name = "cv1800b-rtc" }, + { /* sentinel */ }, +}; +MODULE_DEVICE_TABLE(platform, cv1800_rtc_id); + +static struct platform_driver cv1800_rtc_driver = { + .driver = { + .name = "sophgo-cv1800-rtc", + }, + .probe = cv1800_rtc_probe, + .id_table = cv1800_rtc_id, +}; + +module_platform_driver(cv1800_rtc_driver); +MODULE_AUTHOR("Jingbao Qiu"); +MODULE_DESCRIPTION("Sophgo cv1800 RTC Driver"); +MODULE_LICENSE("GPL"); |