// SPDX-License-Identifier: GPL-2.0 /* * SuperH On-Chip RTC Support * * Copyright (C) 2006 - 2009 Paul Mundt * Copyright (C) 2006 Jamie Lenehan * Copyright (C) 2008 Angelo Castello * * Based on the old arch/sh/kernel/cpu/rtc.c by: * * Copyright (C) 2000 Philipp Rumpf <prumpf@tux.org> * Copyright (C) 1999 Tetsuya Okada & Niibe Yutaka */ #include <linux/module.h> #include <linux/mod_devicetable.h> #include <linux/kernel.h> #include <linux/bcd.h> #include <linux/rtc.h> #include <linux/init.h> #include <linux/platform_device.h> #include <linux/seq_file.h> #include <linux/interrupt.h> #include <linux/spinlock.h> #include <linux/io.h> #include <linux/log2.h> #include <linux/clk.h> #include <linux/slab.h> #ifdef CONFIG_SUPERH #include <asm/rtc.h> #else /* Default values for RZ/A RTC */ #define rtc_reg_size sizeof(u16) #define RTC_BIT_INVERTED 0 /* no chip bugs */ #define RTC_CAP_4_DIGIT_YEAR (1 << 0) #define RTC_DEF_CAPABILITIES RTC_CAP_4_DIGIT_YEAR #endif #define DRV_NAME "sh-rtc" #define RTC_REG(r) ((r) * rtc_reg_size) #define R64CNT RTC_REG(0) #define RSECCNT RTC_REG(1) /* RTC sec */ #define RMINCNT RTC_REG(2) /* RTC min */ #define RHRCNT RTC_REG(3) /* RTC hour */ #define RWKCNT RTC_REG(4) /* RTC week */ #define RDAYCNT RTC_REG(5) /* RTC day */ #define RMONCNT RTC_REG(6) /* RTC month */ #define RYRCNT RTC_REG(7) /* RTC year */ #define RSECAR RTC_REG(8) /* ALARM sec */ #define RMINAR RTC_REG(9) /* ALARM min */ #define RHRAR RTC_REG(10) /* ALARM hour */ #define RWKAR RTC_REG(11) /* ALARM week */ #define RDAYAR RTC_REG(12) /* ALARM day */ #define RMONAR RTC_REG(13) /* ALARM month */ #define RCR1 RTC_REG(14) /* Control */ #define RCR2 RTC_REG(15) /* Control */ /* * Note on RYRAR and RCR3: Up until this point most of the register * definitions are consistent across all of the available parts. However, * the placement of the optional RYRAR and RCR3 (the RYRAR control * register used to control RYRCNT/RYRAR compare) varies considerably * across various parts, occasionally being mapped in to a completely * unrelated address space. For proper RYRAR support a separate resource * would have to be handed off, but as this is purely optional in * practice, we simply opt not to support it, thereby keeping the code * quite a bit more simplified. */ /* ALARM Bits - or with BCD encoded value */ #define AR_ENB 0x80 /* Enable for alarm cmp */ /* Period Bits */ #define PF_HP 0x100 /* Enable Half Period to support 8,32,128Hz */ #define PF_COUNT 0x200 /* Half periodic counter */ #define PF_OXS 0x400 /* Periodic One x Second */ #define PF_KOU 0x800 /* Kernel or User periodic request 1=kernel */ #define PF_MASK 0xf00 /* RCR1 Bits */ #define RCR1_CF 0x80 /* Carry Flag */ #define RCR1_CIE 0x10 /* Carry Interrupt Enable */ #define RCR1_AIE 0x08 /* Alarm Interrupt Enable */ #define RCR1_AF 0x01 /* Alarm Flag */ /* RCR2 Bits */ #define RCR2_PEF 0x80 /* PEriodic interrupt Flag */ #define RCR2_PESMASK 0x70 /* Periodic interrupt Set */ #define RCR2_RTCEN 0x08 /* ENable RTC */ #define RCR2_ADJ 0x04 /* ADJustment (30-second) */ #define RCR2_RESET 0x02 /* Reset bit */ #define RCR2_START 0x01 /* Start bit */ struct sh_rtc { void __iomem *regbase; unsigned long regsize; struct resource *res; int alarm_irq; int periodic_irq; int carry_irq; struct clk *clk; struct rtc_device *rtc_dev; spinlock_t lock; unsigned long capabilities; /* See asm/rtc.h for cap bits */ unsigned short periodic_freq; }; static int __sh_rtc_interrupt(struct sh_rtc *rtc) { unsigned int tmp, pending; tmp = readb(rtc->regbase + RCR1); pending = tmp & RCR1_CF; tmp &= ~RCR1_CF; writeb(tmp, rtc->regbase + RCR1); /* Users have requested One x Second IRQ */ if (pending && rtc->periodic_freq & PF_OXS) rtc_update_irq(rtc->rtc_dev, 1, RTC_UF | RTC_IRQF); return pending; } static int __sh_rtc_alarm(struct sh_rtc *rtc) { unsigned int tmp, pending; tmp = readb(rtc->regbase + RCR1); pending = tmp & RCR1_AF; tmp &= ~(RCR1_AF | RCR1_AIE); writeb(tmp, rtc->regbase + RCR1); if (pending) rtc_update_irq(rtc->rtc_dev, 1, RTC_AF | RTC_IRQF); return pending; } static int __sh_rtc_periodic(struct sh_rtc *rtc) { unsigned int tmp, pending; tmp = readb(rtc->regbase + RCR2); pending = tmp & RCR2_PEF; tmp &= ~RCR2_PEF; writeb(tmp, rtc->regbase + RCR2); if (!pending) return 0; /* Half period enabled than one skipped and the next notified */ if ((rtc->periodic_freq & PF_HP) && (rtc->periodic_freq & PF_COUNT)) rtc->periodic_freq &= ~PF_COUNT; else { if (rtc->periodic_freq & PF_HP) rtc->periodic_freq |= PF_COUNT; rtc_update_irq(rtc->rtc_dev, 1, RTC_PF | RTC_IRQF); } return pending; } static irqreturn_t sh_rtc_interrupt(int irq, void *dev_id) { struct sh_rtc *rtc = dev_id; int ret; spin_lock(&rtc->lock); ret = __sh_rtc_interrupt(rtc); spin_unlock(&rtc->lock); return IRQ_RETVAL(ret); } static irqreturn_t sh_rtc_alarm(int irq, void *dev_id) { struct sh_rtc *rtc = dev_id; int ret; spin_lock(&rtc->lock); ret = __sh_rtc_alarm(rtc); spin_unlock(&rtc->lock); return IRQ_RETVAL(ret); } static irqreturn_t sh_rtc_periodic(int irq, void *dev_id) { struct sh_rtc *rtc = dev_id; int ret; spin_lock(&rtc->lock); ret = __sh_rtc_periodic(rtc); spin_unlock(&rtc->lock); return IRQ_RETVAL(ret); } static irqreturn_t sh_rtc_shared(int irq, void *dev_id) { struct sh_rtc *rtc = dev_id; int ret; spin_lock(&rtc->lock); ret = __sh_rtc_interrupt(rtc); ret |= __sh_rtc_alarm(rtc); ret |= __sh_rtc_periodic(rtc); spin_unlock(&rtc->lock); return IRQ_RETVAL(ret); } static inline void sh_rtc_setaie(struct device *dev, unsigned int enable) { struct sh_rtc *rtc = dev_get_drvdata(dev); unsigned int tmp; spin_lock_irq(&rtc->lock); tmp = readb(rtc->regbase + RCR1); if (enable) tmp |= RCR1_AIE; else tmp &= ~RCR1_AIE; writeb(tmp, rtc->regbase + RCR1); spin_unlock_irq(&rtc->lock); } static int sh_rtc_proc(struct device *dev, struct seq_file *seq) { struct sh_rtc *rtc = dev_get_drvdata(dev); unsigned int tmp; tmp = readb(rtc->regbase + RCR1); seq_printf(seq, "carry_IRQ\t: %s\n", (tmp & RCR1_CIE) ? "yes" : "no"); tmp = readb(rtc->regbase + RCR2); seq_printf(seq, "periodic_IRQ\t: %s\n", (tmp & RCR2_PESMASK) ? "yes" : "no"); return 0; } static inline void sh_rtc_setcie(struct device *dev, unsigned int enable) { struct sh_rtc *rtc = dev_get_drvdata(dev); unsigned int tmp; spin_lock_irq(&rtc->lock); tmp = readb(rtc->regbase + RCR1); if (!enable) tmp &= ~RCR1_CIE; else tmp |= RCR1_CIE; writeb(tmp, rtc->regbase + RCR1); spin_unlock_irq(&rtc->lock); } static int sh_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) { sh_rtc_setaie(dev, enabled); return 0; } static int sh_rtc_read_time(struct device *dev, struct rtc_time *tm) { struct sh_rtc *rtc = dev_get_drvdata(dev); unsigned int sec128, sec2, yr, yr100, cf_bit; if (!(readb(rtc->regbase + RCR2) & RCR2_RTCEN)) return -EINVAL; do { unsigned int tmp; spin_lock_irq(&rtc->lock); tmp = readb(rtc->regbase + RCR1); tmp &= ~RCR1_CF; /* Clear CF-bit */ tmp |= RCR1_CIE; writeb(tmp, rtc->regbase + RCR1); sec128 = readb(rtc->regbase + R64CNT); tm->tm_sec = bcd2bin(readb(rtc->regbase + RSECCNT)); tm->tm_min = bcd2bin(readb(rtc->regbase + RMINCNT)); tm->tm_hour = bcd2bin(readb(rtc->regbase + RHRCNT)); tm->tm_wday = bcd2bin(readb(rtc->regbase + RWKCNT)); tm->tm_mday = bcd2bin(readb(rtc->regbase + RDAYCNT)); tm->tm_mon = bcd2bin(readb(rtc->regbase + RMONCNT)) - 1; if (rtc->capabilities & RTC_CAP_4_DIGIT_YEAR) { yr = readw(rtc->regbase + RYRCNT); yr100 = bcd2bin(yr >> 8); yr &= 0xff; } else { yr = readb(rtc->regbase + RYRCNT); yr100 = bcd2bin((yr == 0x99) ? 0x19 : 0x20); } tm->tm_year = (yr100 * 100 + bcd2bin(yr)) - 1900; sec2 = readb(rtc->regbase + R64CNT); cf_bit = readb(rtc->regbase + RCR1) & RCR1_CF; spin_unlock_irq(&rtc->lock); } while (cf_bit != 0 || ((sec128 ^ sec2) & RTC_BIT_INVERTED) != 0); #if RTC_BIT_INVERTED != 0 if ((sec128 & RTC_BIT_INVERTED)) tm->tm_sec--; #endif /* only keep the carry interrupt enabled if UIE is on */ if (!(rtc->periodic_freq & PF_OXS)) sh_rtc_setcie(dev, 0); dev_dbg(dev, "%s: tm is secs=%d, mins=%d, hours=%d, " "mday=%d, mon=%d, year=%d, wday=%d\n", __func__, tm->tm_sec, tm->tm_min, tm->tm_hour, tm->tm_mday, tm->tm_mon + 1, tm->tm_year, tm->tm_wday); return 0; } static int sh_rtc_set_time(struct device *dev, struct rtc_time *tm) { struct sh_rtc *rtc = dev_get_drvdata(dev); unsigned int tmp; int year; spin_lock_irq(&rtc->lock); /* Reset pre-scaler & stop RTC */ tmp = readb(rtc->regbase + RCR2); tmp |= RCR2_RESET; tmp &= ~RCR2_START; writeb(tmp, rtc->regbase + RCR2); writeb(bin2bcd(tm->tm_sec), rtc->regbase + RSECCNT); writeb(bin2bcd(tm->tm_min), rtc->regbase + RMINCNT); writeb(bin2bcd(tm->tm_hour), rtc->regbase + RHRCNT); writeb(bin2bcd(tm->tm_wday), rtc->regbase + RWKCNT); writeb(bin2bcd(tm->tm_mday), rtc->regbase + RDAYCNT); writeb(bin2bcd(tm->tm_mon + 1), rtc->regbase + RMONCNT); if (rtc->capabilities & RTC_CAP_4_DIGIT_YEAR) { year = (bin2bcd((tm->tm_year + 1900) / 100) << 8) | bin2bcd(tm->tm_year % 100); writew(year, rtc->regbase + RYRCNT); } else { year = tm->tm_year % 100; writeb(bin2bcd(year), rtc->regbase + RYRCNT); } /* Start RTC */ tmp = readb(rtc->regbase + RCR2); tmp &= ~RCR2_RESET; tmp |= RCR2_RTCEN | RCR2_START; writeb(tmp, rtc->regbase + RCR2); spin_unlock_irq(&rtc->lock); return 0; } static inline int sh_rtc_read_alarm_value(struct sh_rtc *rtc, int reg_off) { unsigned int byte; int value = -1; /* return -1 for ignored values */ byte = readb(rtc->regbase + reg_off); if (byte & AR_ENB) { byte &= ~AR_ENB; /* strip the enable bit */ value = bcd2bin(byte); } return value; } static int sh_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *wkalrm) { struct sh_rtc *rtc = dev_get_drvdata(dev); struct rtc_time *tm = &wkalrm->time; spin_lock_irq(&rtc->lock); tm->tm_sec = sh_rtc_read_alarm_value(rtc, RSECAR); tm->tm_min = sh_rtc_read_alarm_value(rtc, RMINAR); tm->tm_hour = sh_rtc_read_alarm_value(rtc, RHRAR); tm->tm_wday = sh_rtc_read_alarm_value(rtc, RWKAR); tm->tm_mday = sh_rtc_read_alarm_value(rtc, RDAYAR); tm->tm_mon = sh_rtc_read_alarm_value(rtc, RMONAR); if (tm->tm_mon > 0) tm->tm_mon -= 1; /* RTC is 1-12, tm_mon is 0-11 */ wkalrm->enabled = (readb(rtc->regbase + RCR1) & RCR1_AIE) ? 1 : 0; spin_unlock_irq(&rtc->lock); return 0; } static inline void sh_rtc_write_alarm_value(struct sh_rtc *rtc, int value, int reg_off) { /* < 0 for a value that is ignored */ if (value < 0) writeb(0, rtc->regbase + reg_off); else writeb(bin2bcd(value) | AR_ENB, rtc->regbase + reg_off); } static int sh_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *wkalrm) { struct sh_rtc *rtc = dev_get_drvdata(dev); unsigned int rcr1; struct rtc_time *tm = &wkalrm->time; int mon; spin_lock_irq(&rtc->lock); /* disable alarm interrupt and clear the alarm flag */ rcr1 = readb(rtc->regbase + RCR1); rcr1 &= ~(RCR1_AF | RCR1_AIE); writeb(rcr1, rtc->regbase + RCR1); /* set alarm time */ sh_rtc_write_alarm_value(rtc, tm->tm_sec, RSECAR); sh_rtc_write_alarm_value(rtc, tm->tm_min, RMINAR); sh_rtc_write_alarm_value(rtc, tm->tm_hour, RHRAR); sh_rtc_write_alarm_value(rtc, tm->tm_wday, RWKAR); sh_rtc_write_alarm_value(rtc, tm->tm_mday, RDAYAR); mon = tm->tm_mon; if (mon >= 0) mon += 1; sh_rtc_write_alarm_value(rtc, mon, RMONAR); if (wkalrm->enabled) { rcr1 |= RCR1_AIE; writeb(rcr1, rtc->regbase + RCR1); } spin_unlock_irq(&rtc->lock); return 0; } static const struct rtc_class_ops sh_rtc_ops = { .read_time = sh_rtc_read_time, .set_time = sh_rtc_set_time, .read_alarm = sh_rtc_read_alarm, .set_alarm = sh_rtc_set_alarm, .proc = sh_rtc_proc, .alarm_irq_enable = sh_rtc_alarm_irq_enable, }; static int __init sh_rtc_probe(struct platform_device *pdev) { struct sh_rtc *rtc; struct resource *res; char clk_name[6]; int clk_id, ret; rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL); if (unlikely(!rtc)) return -ENOMEM; spin_lock_init(&rtc->lock); /* get periodic/carry/alarm irqs */ ret = platform_get_irq(pdev, 0); if (unlikely(ret <= 0)) { dev_err(&pdev->dev, "No IRQ resource\n"); return -ENOENT; } rtc->periodic_irq = ret; rtc->carry_irq = platform_get_irq(pdev, 1); rtc->alarm_irq = platform_get_irq(pdev, 2); res = platform_get_resource(pdev, IORESOURCE_IO, 0); if (!res) res = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (unlikely(res == NULL)) { dev_err(&pdev->dev, "No IO resource\n"); return -ENOENT; } rtc->regsize = resource_size(res); rtc->res = devm_request_mem_region(&pdev->dev, res->start, rtc->regsize, pdev->name); if (unlikely(!rtc->res)) return -EBUSY; rtc->regbase = devm_ioremap(&pdev->dev, rtc->res->start, rtc->regsize); if (unlikely(!rtc->regbase)) return -EINVAL; if (!pdev->dev.of_node) { clk_id = pdev->id; /* With a single device, the clock id is still "rtc0" */ if (clk_id < 0) clk_id = 0; snprintf(clk_name, sizeof(clk_name), "rtc%d", clk_id); } else snprintf(clk_name, sizeof(clk_name), "fck"); rtc->clk = devm_clk_get(&pdev->dev, clk_name); if (IS_ERR(rtc->clk)) { /* * No error handling for rtc->clk intentionally, not all * platforms will have a unique clock for the RTC, and * the clk API can handle the struct clk pointer being * NULL. */ rtc->clk = NULL; } rtc->rtc_dev = devm_rtc_allocate_device(&pdev->dev); if (IS_ERR(rtc->rtc_dev)) return PTR_ERR(rtc->rtc_dev); clk_enable(rtc->clk); rtc->capabilities = RTC_DEF_CAPABILITIES; #ifdef CONFIG_SUPERH if (dev_get_platdata(&pdev->dev)) { struct sh_rtc_platform_info *pinfo = dev_get_platdata(&pdev->dev); /* * Some CPUs have special capabilities in addition to the * default set. Add those in here. */ rtc->capabilities |= pinfo->capabilities; } #endif if (rtc->carry_irq <= 0) { /* register shared periodic/carry/alarm irq */ ret = devm_request_irq(&pdev->dev, rtc->periodic_irq, sh_rtc_shared, 0, "sh-rtc", rtc); if (unlikely(ret)) { dev_err(&pdev->dev, "request IRQ failed with %d, IRQ %d\n", ret, rtc->periodic_irq); goto err_unmap; } } else { /* register periodic/carry/alarm irqs */ ret = devm_request_irq(&pdev->dev, rtc->periodic_irq, sh_rtc_periodic, 0, "sh-rtc period", rtc); if (unlikely(ret)) { dev_err(&pdev->dev, "request period IRQ failed with %d, IRQ %d\n", ret, rtc->periodic_irq); goto err_unmap; } ret = devm_request_irq(&pdev->dev, rtc->carry_irq, sh_rtc_interrupt, 0, "sh-rtc carry", rtc); if (unlikely(ret)) { dev_err(&pdev->dev, "request carry IRQ failed with %d, IRQ %d\n", ret, rtc->carry_irq); goto err_unmap; } ret = devm_request_irq(&pdev->dev, rtc->alarm_irq, sh_rtc_alarm, 0, "sh-rtc alarm", rtc); if (unlikely(ret)) { dev_err(&pdev->dev, "request alarm IRQ failed with %d, IRQ %d\n", ret, rtc->alarm_irq); goto err_unmap; } } platform_set_drvdata(pdev, rtc); /* everything disabled by default */ sh_rtc_setaie(&pdev->dev, 0); sh_rtc_setcie(&pdev->dev, 0); rtc->rtc_dev->ops = &sh_rtc_ops; rtc->rtc_dev->max_user_freq = 256; if (rtc->capabilities & RTC_CAP_4_DIGIT_YEAR) { rtc->rtc_dev->range_min = RTC_TIMESTAMP_BEGIN_1900; rtc->rtc_dev->range_max = RTC_TIMESTAMP_END_9999; } else { rtc->rtc_dev->range_min = mktime64(1999, 1, 1, 0, 0, 0); rtc->rtc_dev->range_max = mktime64(2098, 12, 31, 23, 59, 59); } ret = rtc_register_device(rtc->rtc_dev); if (ret) goto err_unmap; device_init_wakeup(&pdev->dev, 1); return 0; err_unmap: clk_disable(rtc->clk); return ret; } static int __exit sh_rtc_remove(struct platform_device *pdev) { struct sh_rtc *rtc = platform_get_drvdata(pdev); sh_rtc_setaie(&pdev->dev, 0); sh_rtc_setcie(&pdev->dev, 0); clk_disable(rtc->clk); return 0; } static void sh_rtc_set_irq_wake(struct device *dev, int enabled) { struct sh_rtc *rtc = dev_get_drvdata(dev); irq_set_irq_wake(rtc->periodic_irq, enabled); if (rtc->carry_irq > 0) { irq_set_irq_wake(rtc->carry_irq, enabled); irq_set_irq_wake(rtc->alarm_irq, enabled); } } static int __maybe_unused sh_rtc_suspend(struct device *dev) { if (device_may_wakeup(dev)) sh_rtc_set_irq_wake(dev, 1); return 0; } static int __maybe_unused sh_rtc_resume(struct device *dev) { if (device_may_wakeup(dev)) sh_rtc_set_irq_wake(dev, 0); return 0; } static SIMPLE_DEV_PM_OPS(sh_rtc_pm_ops, sh_rtc_suspend, sh_rtc_resume); static const struct of_device_id sh_rtc_of_match[] = { { .compatible = "renesas,sh-rtc", }, { /* sentinel */ } }; MODULE_DEVICE_TABLE(of, sh_rtc_of_match); static struct platform_driver sh_rtc_platform_driver = { .driver = { .name = DRV_NAME, .pm = &sh_rtc_pm_ops, .of_match_table = sh_rtc_of_match, }, .remove = __exit_p(sh_rtc_remove), }; module_platform_driver_probe(sh_rtc_platform_driver, sh_rtc_probe); MODULE_DESCRIPTION("SuperH on-chip RTC driver"); MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>, " "Jamie Lenehan <lenehan@twibble.org>, " "Angelo Castello <angelo.castello@st.com>"); MODULE_LICENSE("GPL v2"); MODULE_ALIAS("platform:" DRV_NAME);