/* * drivers/rtc/rtc-vt8500.c * * Copyright (C) 2010 Alexey Charkov <alchark@gmail.com> * * Based on rtc-pxa.c * * This software is licensed under the terms of the GNU General Public * License version 2, as published by the Free Software Foundation, and * may be copied, distributed, and modified under those terms. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. */ #include <linux/module.h> #include <linux/rtc.h> #include <linux/init.h> #include <linux/interrupt.h> #include <linux/io.h> #include <linux/bcd.h> #include <linux/platform_device.h> #include <linux/slab.h> /* * Register definitions */ #define VT8500_RTC_TS 0x00 /* Time set */ #define VT8500_RTC_DS 0x04 /* Date set */ #define VT8500_RTC_AS 0x08 /* Alarm set */ #define VT8500_RTC_CR 0x0c /* Control */ #define VT8500_RTC_TR 0x10 /* Time read */ #define VT8500_RTC_DR 0x14 /* Date read */ #define VT8500_RTC_WS 0x18 /* Write status */ #define VT8500_RTC_CL 0x20 /* Calibration */ #define VT8500_RTC_IS 0x24 /* Interrupt status */ #define VT8500_RTC_ST 0x28 /* Status */ #define INVALID_TIME_BIT (1 << 31) #define DATE_CENTURY_S 19 #define DATE_YEAR_S 11 #define DATE_YEAR_MASK (0xff << DATE_YEAR_S) #define DATE_MONTH_S 6 #define DATE_MONTH_MASK (0x1f << DATE_MONTH_S) #define DATE_DAY_MASK 0x3f #define TIME_DOW_S 20 #define TIME_DOW_MASK (0x07 << TIME_DOW_S) #define TIME_HOUR_S 14 #define TIME_HOUR_MASK (0x3f << TIME_HOUR_S) #define TIME_MIN_S 7 #define TIME_MIN_MASK (0x7f << TIME_MIN_S) #define TIME_SEC_MASK 0x7f #define ALARM_DAY_S 20 #define ALARM_DAY_MASK (0x3f << ALARM_DAY_S) #define ALARM_DAY_BIT (1 << 29) #define ALARM_HOUR_BIT (1 << 28) #define ALARM_MIN_BIT (1 << 27) #define ALARM_SEC_BIT (1 << 26) #define ALARM_ENABLE_MASK (ALARM_DAY_BIT \ | ALARM_HOUR_BIT \ | ALARM_MIN_BIT \ | ALARM_SEC_BIT) #define VT8500_RTC_CR_ENABLE (1 << 0) /* Enable RTC */ #define VT8500_RTC_CR_24H (1 << 1) /* 24h time format */ #define VT8500_RTC_CR_SM_ENABLE (1 << 2) /* Enable periodic irqs */ #define VT8500_RTC_CR_SM_SEC (1 << 3) /* 0: 1Hz/60, 1: 1Hz */ #define VT8500_RTC_CR_CALIB (1 << 4) /* Enable calibration */ #define VT8500_RTC_IS_ALARM (1 << 0) /* Alarm interrupt status */ struct vt8500_rtc { void __iomem *regbase; struct resource *res; int irq_alarm; struct rtc_device *rtc; spinlock_t lock; /* Protects this structure */ }; static irqreturn_t vt8500_rtc_irq(int irq, void *dev_id) { struct vt8500_rtc *vt8500_rtc = dev_id; u32 isr; unsigned long events = 0; spin_lock(&vt8500_rtc->lock); /* clear interrupt sources */ isr = readl(vt8500_rtc->regbase + VT8500_RTC_IS); writel(isr, vt8500_rtc->regbase + VT8500_RTC_IS); spin_unlock(&vt8500_rtc->lock); if (isr & VT8500_RTC_IS_ALARM) events |= RTC_AF | RTC_IRQF; rtc_update_irq(vt8500_rtc->rtc, 1, events); return IRQ_HANDLED; } static int vt8500_rtc_read_time(struct device *dev, struct rtc_time *tm) { struct vt8500_rtc *vt8500_rtc = dev_get_drvdata(dev); u32 date, time; date = readl(vt8500_rtc->regbase + VT8500_RTC_DR); time = readl(vt8500_rtc->regbase + VT8500_RTC_TR); tm->tm_sec = bcd2bin(time & TIME_SEC_MASK); tm->tm_min = bcd2bin((time & TIME_MIN_MASK) >> TIME_MIN_S); tm->tm_hour = bcd2bin((time & TIME_HOUR_MASK) >> TIME_HOUR_S); tm->tm_mday = bcd2bin(date & DATE_DAY_MASK); tm->tm_mon = bcd2bin((date & DATE_MONTH_MASK) >> DATE_MONTH_S); tm->tm_year = bcd2bin((date & DATE_YEAR_MASK) >> DATE_YEAR_S) + ((date >> DATE_CENTURY_S) & 1 ? 200 : 100); tm->tm_wday = (time & TIME_DOW_MASK) >> TIME_DOW_S; return 0; } static int vt8500_rtc_set_time(struct device *dev, struct rtc_time *tm) { struct vt8500_rtc *vt8500_rtc = dev_get_drvdata(dev); if (tm->tm_year < 100) { dev_warn(dev, "Only years 2000-2199 are supported by the " "hardware!\n"); return -EINVAL; } writel((bin2bcd(tm->tm_year - 100) << DATE_YEAR_S) | (bin2bcd(tm->tm_mon) << DATE_MONTH_S) | (bin2bcd(tm->tm_mday)), vt8500_rtc->regbase + VT8500_RTC_DS); writel((bin2bcd(tm->tm_wday) << TIME_DOW_S) | (bin2bcd(tm->tm_hour) << TIME_HOUR_S) | (bin2bcd(tm->tm_min) << TIME_MIN_S) | (bin2bcd(tm->tm_sec)), vt8500_rtc->regbase + VT8500_RTC_TS); return 0; } static int vt8500_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) { struct vt8500_rtc *vt8500_rtc = dev_get_drvdata(dev); u32 isr, alarm; alarm = readl(vt8500_rtc->regbase + VT8500_RTC_AS); isr = readl(vt8500_rtc->regbase + VT8500_RTC_IS); alrm->time.tm_mday = bcd2bin((alarm & ALARM_DAY_MASK) >> ALARM_DAY_S); alrm->time.tm_hour = bcd2bin((alarm & TIME_HOUR_MASK) >> TIME_HOUR_S); alrm->time.tm_min = bcd2bin((alarm & TIME_MIN_MASK) >> TIME_MIN_S); alrm->time.tm_sec = bcd2bin((alarm & TIME_SEC_MASK)); alrm->enabled = (alarm & ALARM_ENABLE_MASK) ? 1 : 0; alrm->pending = (isr & VT8500_RTC_IS_ALARM) ? 1 : 0; return rtc_valid_tm(&alrm->time); } static int vt8500_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) { struct vt8500_rtc *vt8500_rtc = dev_get_drvdata(dev); writel((alrm->enabled ? ALARM_ENABLE_MASK : 0) | (bin2bcd(alrm->time.tm_mday) << ALARM_DAY_S) | (bin2bcd(alrm->time.tm_hour) << TIME_HOUR_S) | (bin2bcd(alrm->time.tm_min) << TIME_MIN_S) | (bin2bcd(alrm->time.tm_sec)), vt8500_rtc->regbase + VT8500_RTC_AS); return 0; } static int vt8500_alarm_irq_enable(struct device *dev, unsigned int enabled) { struct vt8500_rtc *vt8500_rtc = dev_get_drvdata(dev); unsigned long tmp = readl(vt8500_rtc->regbase + VT8500_RTC_AS); if (enabled) tmp |= ALARM_ENABLE_MASK; else tmp &= ~ALARM_ENABLE_MASK; writel(tmp, vt8500_rtc->regbase + VT8500_RTC_AS); return 0; } static const struct rtc_class_ops vt8500_rtc_ops = { .read_time = vt8500_rtc_read_time, .set_time = vt8500_rtc_set_time, .read_alarm = vt8500_rtc_read_alarm, .set_alarm = vt8500_rtc_set_alarm, .alarm_irq_enable = vt8500_alarm_irq_enable, }; static int __devinit vt8500_rtc_probe(struct platform_device *pdev) { struct vt8500_rtc *vt8500_rtc; int ret; vt8500_rtc = kzalloc(sizeof(struct vt8500_rtc), GFP_KERNEL); if (!vt8500_rtc) return -ENOMEM; spin_lock_init(&vt8500_rtc->lock); platform_set_drvdata(pdev, vt8500_rtc); vt8500_rtc->res = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!vt8500_rtc->res) { dev_err(&pdev->dev, "No I/O memory resource defined\n"); ret = -ENXIO; goto err_free; } vt8500_rtc->irq_alarm = platform_get_irq(pdev, 0); if (vt8500_rtc->irq_alarm < 0) { dev_err(&pdev->dev, "No alarm IRQ resource defined\n"); ret = -ENXIO; goto err_free; } vt8500_rtc->res = request_mem_region(vt8500_rtc->res->start, resource_size(vt8500_rtc->res), "vt8500-rtc"); if (vt8500_rtc->res == NULL) { dev_err(&pdev->dev, "failed to request I/O memory\n"); ret = -EBUSY; goto err_free; } vt8500_rtc->regbase = ioremap(vt8500_rtc->res->start, resource_size(vt8500_rtc->res)); if (!vt8500_rtc->regbase) { dev_err(&pdev->dev, "Unable to map RTC I/O memory\n"); ret = -EBUSY; goto err_release; } /* Enable RTC and set it to 24-hour mode */ writel(VT8500_RTC_CR_ENABLE | VT8500_RTC_CR_24H, vt8500_rtc->regbase + VT8500_RTC_CR); vt8500_rtc->rtc = rtc_device_register("vt8500-rtc", &pdev->dev, &vt8500_rtc_ops, THIS_MODULE); if (IS_ERR(vt8500_rtc->rtc)) { ret = PTR_ERR(vt8500_rtc->rtc); dev_err(&pdev->dev, "Failed to register RTC device -> %d\n", ret); goto err_unmap; } ret = request_irq(vt8500_rtc->irq_alarm, vt8500_rtc_irq, 0, "rtc alarm", vt8500_rtc); if (ret < 0) { dev_err(&pdev->dev, "can't get irq %i, err %d\n", vt8500_rtc->irq_alarm, ret); goto err_unreg; } return 0; err_unreg: rtc_device_unregister(vt8500_rtc->rtc); err_unmap: iounmap(vt8500_rtc->regbase); err_release: release_mem_region(vt8500_rtc->res->start, resource_size(vt8500_rtc->res)); err_free: kfree(vt8500_rtc); return ret; } static int __devexit vt8500_rtc_remove(struct platform_device *pdev) { struct vt8500_rtc *vt8500_rtc = platform_get_drvdata(pdev); free_irq(vt8500_rtc->irq_alarm, vt8500_rtc); rtc_device_unregister(vt8500_rtc->rtc); /* Disable alarm matching */ writel(0, vt8500_rtc->regbase + VT8500_RTC_IS); iounmap(vt8500_rtc->regbase); release_mem_region(vt8500_rtc->res->start, resource_size(vt8500_rtc->res)); kfree(vt8500_rtc); platform_set_drvdata(pdev, NULL); return 0; } static struct platform_driver vt8500_rtc_driver = { .probe = vt8500_rtc_probe, .remove = __devexit_p(vt8500_rtc_remove), .driver = { .name = "vt8500-rtc", .owner = THIS_MODULE, }, }; module_platform_driver(vt8500_rtc_driver); MODULE_AUTHOR("Alexey Charkov <alchark@gmail.com>"); MODULE_DESCRIPTION("VIA VT8500 SoC Realtime Clock Driver (RTC)"); MODULE_LICENSE("GPL"); MODULE_ALIAS("platform:vt8500-rtc");