/* * linux/drivers/rtc/rtc-pl030.c * * Copyright (C) 2000-2001 Deep Blue Solutions Ltd. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ #include <linux/module.h> #include <linux/rtc.h> #include <linux/init.h> #include <linux/interrupt.h> #include <linux/amba/bus.h> #include <linux/io.h> #include <linux/slab.h> #define RTC_DR (0) #define RTC_MR (4) #define RTC_STAT (8) #define RTC_EOI (8) #define RTC_LR (12) #define RTC_CR (16) #define RTC_CR_MIE (1 << 0) struct pl030_rtc { struct rtc_device *rtc; void __iomem *base; }; static irqreturn_t pl030_interrupt(int irq, void *dev_id) { struct pl030_rtc *rtc = dev_id; writel(0, rtc->base + RTC_EOI); return IRQ_HANDLED; } static int pl030_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) { struct pl030_rtc *rtc = dev_get_drvdata(dev); rtc_time_to_tm(readl(rtc->base + RTC_MR), &alrm->time); return 0; } static int pl030_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) { struct pl030_rtc *rtc = dev_get_drvdata(dev); unsigned long time; int ret; /* * At the moment, we can only deal with non-wildcarded alarm times. */ ret = rtc_valid_tm(&alrm->time); if (ret == 0) ret = rtc_tm_to_time(&alrm->time, &time); if (ret == 0) writel(time, rtc->base + RTC_MR); return ret; } static int pl030_read_time(struct device *dev, struct rtc_time *tm) { struct pl030_rtc *rtc = dev_get_drvdata(dev); rtc_time_to_tm(readl(rtc->base + RTC_DR), tm); return 0; } /* * Set the RTC time. Unfortunately, we can't accurately set * the point at which the counter updates. * * Also, since RTC_LR is transferred to RTC_CR on next rising * edge of the 1Hz clock, we must write the time one second * in advance. */ static int pl030_set_time(struct device *dev, struct rtc_time *tm) { struct pl030_rtc *rtc = dev_get_drvdata(dev); unsigned long time; int ret; ret = rtc_tm_to_time(tm, &time); if (ret == 0) writel(time + 1, rtc->base + RTC_LR); return ret; } static const struct rtc_class_ops pl030_ops = { .read_time = pl030_read_time, .set_time = pl030_set_time, .read_alarm = pl030_read_alarm, .set_alarm = pl030_set_alarm, }; static int pl030_probe(struct amba_device *dev, const struct amba_id *id) { struct pl030_rtc *rtc; int ret; ret = amba_request_regions(dev, NULL); if (ret) goto err_req; rtc = devm_kzalloc(&dev->dev, sizeof(*rtc), GFP_KERNEL); if (!rtc) { ret = -ENOMEM; goto err_rtc; } rtc->rtc = devm_rtc_allocate_device(&dev->dev); if (IS_ERR(rtc->rtc)) { ret = PTR_ERR(rtc->rtc); goto err_rtc; } rtc->rtc->ops = &pl030_ops; rtc->base = ioremap(dev->res.start, resource_size(&dev->res)); if (!rtc->base) { ret = -ENOMEM; goto err_rtc; } __raw_writel(0, rtc->base + RTC_CR); __raw_writel(0, rtc->base + RTC_EOI); amba_set_drvdata(dev, rtc); ret = request_irq(dev->irq[0], pl030_interrupt, 0, "rtc-pl030", rtc); if (ret) goto err_irq; ret = rtc_register_device(rtc->rtc); if (ret) goto err_reg; return 0; err_reg: free_irq(dev->irq[0], rtc); err_irq: iounmap(rtc->base); err_rtc: amba_release_regions(dev); err_req: return ret; } static int pl030_remove(struct amba_device *dev) { struct pl030_rtc *rtc = amba_get_drvdata(dev); writel(0, rtc->base + RTC_CR); free_irq(dev->irq[0], rtc); iounmap(rtc->base); amba_release_regions(dev); return 0; } static struct amba_id pl030_ids[] = { { .id = 0x00041030, .mask = 0x000fffff, }, { 0, 0 }, }; MODULE_DEVICE_TABLE(amba, pl030_ids); static struct amba_driver pl030_driver = { .drv = { .name = "rtc-pl030", }, .probe = pl030_probe, .remove = pl030_remove, .id_table = pl030_ids, }; module_amba_driver(pl030_driver); MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>"); MODULE_DESCRIPTION("ARM AMBA PL030 RTC Driver"); MODULE_LICENSE("GPL");