diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/rtc/rtc-mt2712.c | 413 |
1 files changed, 413 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-mt2712.c b/drivers/rtc/rtc-mt2712.c new file mode 100644 index 000000000..cd92a9788 --- /dev/null +++ b/drivers/rtc/rtc-mt2712.c @@ -0,0 +1,413 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2019 MediaTek Inc. + * Author: Ran Bi <ran.bi@mediatek.com> + */ + +#include <linux/delay.h> +#include <linux/init.h> +#include <linux/io.h> +#include <linux/irqdomain.h> +#include <linux/module.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/platform_device.h> +#include <linux/rtc.h> + +#define MT2712_BBPU 0x0000 +#define MT2712_BBPU_CLRPKY BIT(4) +#define MT2712_BBPU_RELOAD BIT(5) +#define MT2712_BBPU_CBUSY BIT(6) +#define MT2712_BBPU_KEY (0x43 << 8) + +#define MT2712_IRQ_STA 0x0004 +#define MT2712_IRQ_STA_AL BIT(0) +#define MT2712_IRQ_STA_TC BIT(1) + +#define MT2712_IRQ_EN 0x0008 +#define MT2712_IRQ_EN_AL BIT(0) +#define MT2712_IRQ_EN_TC BIT(1) +#define MT2712_IRQ_EN_ONESHOT BIT(2) + +#define MT2712_CII_EN 0x000c + +#define MT2712_AL_MASK 0x0010 +#define MT2712_AL_MASK_DOW BIT(4) + +#define MT2712_TC_SEC 0x0014 +#define MT2712_TC_MIN 0x0018 +#define MT2712_TC_HOU 0x001c +#define MT2712_TC_DOM 0x0020 +#define MT2712_TC_DOW 0x0024 +#define MT2712_TC_MTH 0x0028 +#define MT2712_TC_YEA 0x002c + +#define MT2712_AL_SEC 0x0030 +#define MT2712_AL_MIN 0x0034 +#define MT2712_AL_HOU 0x0038 +#define MT2712_AL_DOM 0x003c +#define MT2712_AL_DOW 0x0040 +#define MT2712_AL_MTH 0x0044 +#define MT2712_AL_YEA 0x0048 + +#define MT2712_SEC_MASK 0x003f +#define MT2712_MIN_MASK 0x003f +#define MT2712_HOU_MASK 0x001f +#define MT2712_DOM_MASK 0x001f +#define MT2712_DOW_MASK 0x0007 +#define MT2712_MTH_MASK 0x000f +#define MT2712_YEA_MASK 0x007f + +#define MT2712_POWERKEY1 0x004c +#define MT2712_POWERKEY2 0x0050 +#define MT2712_POWERKEY1_KEY 0xa357 +#define MT2712_POWERKEY2_KEY 0x67d2 + +#define MT2712_CON0 0x005c +#define MT2712_CON1 0x0060 + +#define MT2712_PROT 0x0070 +#define MT2712_PROT_UNLOCK1 0x9136 +#define MT2712_PROT_UNLOCK2 0x586a + +#define MT2712_WRTGR 0x0078 + +#define MT2712_RTC_TIMESTAMP_END_2127 4985971199LL + +struct mt2712_rtc { + struct rtc_device *rtc; + void __iomem *base; + int irq; + u8 irq_wake_enabled; + u8 powerlost; +}; + +static inline u32 mt2712_readl(struct mt2712_rtc *mt2712_rtc, u32 reg) +{ + return readl(mt2712_rtc->base + reg); +} + +static inline void mt2712_writel(struct mt2712_rtc *mt2712_rtc, + u32 reg, u32 val) +{ + writel(val, mt2712_rtc->base + reg); +} + +static void mt2712_rtc_write_trigger(struct mt2712_rtc *mt2712_rtc) +{ + unsigned long timeout = jiffies + HZ / 10; + + mt2712_writel(mt2712_rtc, MT2712_WRTGR, 1); + while (1) { + if (!(mt2712_readl(mt2712_rtc, MT2712_BBPU) + & MT2712_BBPU_CBUSY)) + break; + + if (time_after(jiffies, timeout)) { + dev_err(&mt2712_rtc->rtc->dev, + "%s time out!\n", __func__); + break; + } + cpu_relax(); + } +} + +static void mt2712_rtc_writeif_unlock(struct mt2712_rtc *mt2712_rtc) +{ + mt2712_writel(mt2712_rtc, MT2712_PROT, MT2712_PROT_UNLOCK1); + mt2712_rtc_write_trigger(mt2712_rtc); + mt2712_writel(mt2712_rtc, MT2712_PROT, MT2712_PROT_UNLOCK2); + mt2712_rtc_write_trigger(mt2712_rtc); +} + +static irqreturn_t rtc_irq_handler_thread(int irq, void *data) +{ + struct mt2712_rtc *mt2712_rtc = data; + u16 irqsta; + + /* Clear interrupt */ + irqsta = mt2712_readl(mt2712_rtc, MT2712_IRQ_STA); + if (irqsta & MT2712_IRQ_STA_AL) { + rtc_update_irq(mt2712_rtc->rtc, 1, RTC_IRQF | RTC_AF); + return IRQ_HANDLED; + } + + return IRQ_NONE; +} + +static void __mt2712_rtc_read_time(struct mt2712_rtc *mt2712_rtc, + struct rtc_time *tm, int *sec) +{ + tm->tm_sec = mt2712_readl(mt2712_rtc, MT2712_TC_SEC) + & MT2712_SEC_MASK; + tm->tm_min = mt2712_readl(mt2712_rtc, MT2712_TC_MIN) + & MT2712_MIN_MASK; + tm->tm_hour = mt2712_readl(mt2712_rtc, MT2712_TC_HOU) + & MT2712_HOU_MASK; + tm->tm_mday = mt2712_readl(mt2712_rtc, MT2712_TC_DOM) + & MT2712_DOM_MASK; + tm->tm_mon = (mt2712_readl(mt2712_rtc, MT2712_TC_MTH) - 1) + & MT2712_MTH_MASK; + tm->tm_year = (mt2712_readl(mt2712_rtc, MT2712_TC_YEA) + 100) + & MT2712_YEA_MASK; + + *sec = mt2712_readl(mt2712_rtc, MT2712_TC_SEC) & MT2712_SEC_MASK; +} + +static int mt2712_rtc_read_time(struct device *dev, struct rtc_time *tm) +{ + struct mt2712_rtc *mt2712_rtc = dev_get_drvdata(dev); + int sec; + + if (mt2712_rtc->powerlost) + return -EINVAL; + + do { + __mt2712_rtc_read_time(mt2712_rtc, tm, &sec); + } while (sec < tm->tm_sec); /* SEC has carried */ + + return 0; +} + +static int mt2712_rtc_set_time(struct device *dev, struct rtc_time *tm) +{ + struct mt2712_rtc *mt2712_rtc = dev_get_drvdata(dev); + + mt2712_writel(mt2712_rtc, MT2712_TC_SEC, tm->tm_sec & MT2712_SEC_MASK); + mt2712_writel(mt2712_rtc, MT2712_TC_MIN, tm->tm_min & MT2712_MIN_MASK); + mt2712_writel(mt2712_rtc, MT2712_TC_HOU, tm->tm_hour & MT2712_HOU_MASK); + mt2712_writel(mt2712_rtc, MT2712_TC_DOM, tm->tm_mday & MT2712_DOM_MASK); + mt2712_writel(mt2712_rtc, MT2712_TC_MTH, + (tm->tm_mon + 1) & MT2712_MTH_MASK); + mt2712_writel(mt2712_rtc, MT2712_TC_YEA, + (tm->tm_year - 100) & MT2712_YEA_MASK); + + mt2712_rtc_write_trigger(mt2712_rtc); + + if (mt2712_rtc->powerlost) + mt2712_rtc->powerlost = false; + + return 0; +} + +static int mt2712_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm) +{ + struct mt2712_rtc *mt2712_rtc = dev_get_drvdata(dev); + struct rtc_time *tm = &alm->time; + u16 irqen; + + irqen = mt2712_readl(mt2712_rtc, MT2712_IRQ_EN); + alm->enabled = !!(irqen & MT2712_IRQ_EN_AL); + + tm->tm_sec = mt2712_readl(mt2712_rtc, MT2712_AL_SEC) & MT2712_SEC_MASK; + tm->tm_min = mt2712_readl(mt2712_rtc, MT2712_AL_MIN) & MT2712_MIN_MASK; + tm->tm_hour = mt2712_readl(mt2712_rtc, MT2712_AL_HOU) & MT2712_HOU_MASK; + tm->tm_mday = mt2712_readl(mt2712_rtc, MT2712_AL_DOM) & MT2712_DOM_MASK; + tm->tm_mon = (mt2712_readl(mt2712_rtc, MT2712_AL_MTH) - 1) + & MT2712_MTH_MASK; + tm->tm_year = (mt2712_readl(mt2712_rtc, MT2712_AL_YEA) + 100) + & MT2712_YEA_MASK; + + return 0; +} + +static int mt2712_rtc_alarm_irq_enable(struct device *dev, + unsigned int enabled) +{ + struct mt2712_rtc *mt2712_rtc = dev_get_drvdata(dev); + u16 irqen; + + irqen = mt2712_readl(mt2712_rtc, MT2712_IRQ_EN); + if (enabled) + irqen |= MT2712_IRQ_EN_AL; + else + irqen &= ~MT2712_IRQ_EN_AL; + mt2712_writel(mt2712_rtc, MT2712_IRQ_EN, irqen); + mt2712_rtc_write_trigger(mt2712_rtc); + + return 0; +} + +static int mt2712_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm) +{ + struct mt2712_rtc *mt2712_rtc = dev_get_drvdata(dev); + struct rtc_time *tm = &alm->time; + + dev_dbg(&mt2712_rtc->rtc->dev, "set al time: %ptR, alm en: %d\n", + tm, alm->enabled); + + mt2712_writel(mt2712_rtc, MT2712_AL_SEC, + (mt2712_readl(mt2712_rtc, MT2712_AL_SEC) + & ~(MT2712_SEC_MASK)) | (tm->tm_sec & MT2712_SEC_MASK)); + mt2712_writel(mt2712_rtc, MT2712_AL_MIN, + (mt2712_readl(mt2712_rtc, MT2712_AL_MIN) + & ~(MT2712_MIN_MASK)) | (tm->tm_min & MT2712_MIN_MASK)); + mt2712_writel(mt2712_rtc, MT2712_AL_HOU, + (mt2712_readl(mt2712_rtc, MT2712_AL_HOU) + & ~(MT2712_HOU_MASK)) | (tm->tm_hour & MT2712_HOU_MASK)); + mt2712_writel(mt2712_rtc, MT2712_AL_DOM, + (mt2712_readl(mt2712_rtc, MT2712_AL_DOM) + & ~(MT2712_DOM_MASK)) | (tm->tm_mday & MT2712_DOM_MASK)); + mt2712_writel(mt2712_rtc, MT2712_AL_MTH, + (mt2712_readl(mt2712_rtc, MT2712_AL_MTH) + & ~(MT2712_MTH_MASK)) + | ((tm->tm_mon + 1) & MT2712_MTH_MASK)); + mt2712_writel(mt2712_rtc, MT2712_AL_YEA, + (mt2712_readl(mt2712_rtc, MT2712_AL_YEA) + & ~(MT2712_YEA_MASK)) + | ((tm->tm_year - 100) & MT2712_YEA_MASK)); + + /* mask day of week */ + mt2712_writel(mt2712_rtc, MT2712_AL_MASK, MT2712_AL_MASK_DOW); + mt2712_rtc_write_trigger(mt2712_rtc); + + mt2712_rtc_alarm_irq_enable(dev, alm->enabled); + + return 0; +} + +/* Init RTC register */ +static void mt2712_rtc_hw_init(struct mt2712_rtc *mt2712_rtc) +{ + u32 p1, p2; + + mt2712_writel(mt2712_rtc, MT2712_BBPU, + MT2712_BBPU_KEY | MT2712_BBPU_RELOAD); + + mt2712_writel(mt2712_rtc, MT2712_CII_EN, 0); + mt2712_writel(mt2712_rtc, MT2712_AL_MASK, 0); + /* necessary before set MT2712_POWERKEY */ + mt2712_writel(mt2712_rtc, MT2712_CON0, 0x4848); + mt2712_writel(mt2712_rtc, MT2712_CON1, 0x0048); + + mt2712_rtc_write_trigger(mt2712_rtc); + + p1 = mt2712_readl(mt2712_rtc, MT2712_POWERKEY1); + p2 = mt2712_readl(mt2712_rtc, MT2712_POWERKEY2); + if (p1 != MT2712_POWERKEY1_KEY || p2 != MT2712_POWERKEY2_KEY) { + mt2712_rtc->powerlost = true; + dev_dbg(&mt2712_rtc->rtc->dev, + "powerkey not set (lost power)\n"); + } else { + mt2712_rtc->powerlost = false; + } + + /* RTC need POWERKEY1/2 match, then goto normal work mode */ + mt2712_writel(mt2712_rtc, MT2712_POWERKEY1, MT2712_POWERKEY1_KEY); + mt2712_writel(mt2712_rtc, MT2712_POWERKEY2, MT2712_POWERKEY2_KEY); + mt2712_rtc_write_trigger(mt2712_rtc); + + mt2712_rtc_writeif_unlock(mt2712_rtc); +} + +static const struct rtc_class_ops mt2712_rtc_ops = { + .read_time = mt2712_rtc_read_time, + .set_time = mt2712_rtc_set_time, + .read_alarm = mt2712_rtc_read_alarm, + .set_alarm = mt2712_rtc_set_alarm, + .alarm_irq_enable = mt2712_rtc_alarm_irq_enable, +}; + +static int mt2712_rtc_probe(struct platform_device *pdev) +{ + struct mt2712_rtc *mt2712_rtc; + int ret; + + mt2712_rtc = devm_kzalloc(&pdev->dev, + sizeof(struct mt2712_rtc), GFP_KERNEL); + if (!mt2712_rtc) + return -ENOMEM; + + mt2712_rtc->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(mt2712_rtc->base)) + return PTR_ERR(mt2712_rtc->base); + + /* rtc hw init */ + mt2712_rtc_hw_init(mt2712_rtc); + + mt2712_rtc->irq = platform_get_irq(pdev, 0); + if (mt2712_rtc->irq < 0) + return mt2712_rtc->irq; + + platform_set_drvdata(pdev, mt2712_rtc); + + mt2712_rtc->rtc = devm_rtc_allocate_device(&pdev->dev); + if (IS_ERR(mt2712_rtc->rtc)) + return PTR_ERR(mt2712_rtc->rtc); + + ret = devm_request_threaded_irq(&pdev->dev, mt2712_rtc->irq, NULL, + rtc_irq_handler_thread, + IRQF_ONESHOT | IRQF_TRIGGER_LOW, + dev_name(&mt2712_rtc->rtc->dev), + mt2712_rtc); + if (ret) { + dev_err(&pdev->dev, "Failed to request alarm IRQ: %d: %d\n", + mt2712_rtc->irq, ret); + return ret; + } + + device_init_wakeup(&pdev->dev, true); + + mt2712_rtc->rtc->ops = &mt2712_rtc_ops; + mt2712_rtc->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000; + mt2712_rtc->rtc->range_max = MT2712_RTC_TIMESTAMP_END_2127; + + return devm_rtc_register_device(mt2712_rtc->rtc); +} + +#ifdef CONFIG_PM_SLEEP +static int mt2712_rtc_suspend(struct device *dev) +{ + int wake_status = 0; + struct mt2712_rtc *mt2712_rtc = dev_get_drvdata(dev); + + if (device_may_wakeup(dev)) { + wake_status = enable_irq_wake(mt2712_rtc->irq); + if (!wake_status) + mt2712_rtc->irq_wake_enabled = true; + } + + return 0; +} + +static int mt2712_rtc_resume(struct device *dev) +{ + int wake_status = 0; + struct mt2712_rtc *mt2712_rtc = dev_get_drvdata(dev); + + if (device_may_wakeup(dev) && mt2712_rtc->irq_wake_enabled) { + wake_status = disable_irq_wake(mt2712_rtc->irq); + if (!wake_status) + mt2712_rtc->irq_wake_enabled = false; + } + + return 0; +} + +static SIMPLE_DEV_PM_OPS(mt2712_pm_ops, mt2712_rtc_suspend, + mt2712_rtc_resume); +#endif + +static const struct of_device_id mt2712_rtc_of_match[] = { + { .compatible = "mediatek,mt2712-rtc", }, + { }, +}; + +MODULE_DEVICE_TABLE(of, mt2712_rtc_of_match); + +static struct platform_driver mt2712_rtc_driver = { + .driver = { + .name = "mt2712-rtc", + .of_match_table = mt2712_rtc_of_match, +#ifdef CONFIG_PM_SLEEP + .pm = &mt2712_pm_ops, +#endif + }, + .probe = mt2712_rtc_probe, +}; + +module_platform_driver(mt2712_rtc_driver); + +MODULE_DESCRIPTION("MediaTek MT2712 SoC based RTC Driver"); +MODULE_AUTHOR("Ran Bi <ran.bi@mediatek.com>"); +MODULE_LICENSE("GPL"); |