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(I'm so sorry!) Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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#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 BIT(7) /* Enable for alarm cmp */
/* RCR1 Bits */#define RCR1_CF BIT(7) /* Carry Flag */#define RCR1_CIE BIT(4) /* Carry Interrupt Enable */#define RCR1_AIE BIT(3) /* Alarm Interrupt Enable */#define RCR1_AF BIT(0) /* Alarm Flag */
/* RCR2 Bits */#define RCR2_RTCEN BIT(3) /* ENable RTC */#define RCR2_ADJ BIT(2) /* ADJustment (30-second) */#define RCR2_RESET BIT(1) /* Reset bit */#define RCR2_START BIT(0) /* Start bit */
struct sh_rtc { void __iomem *regbase; int alarm_irq; struct clk *clk; struct rtc_device *rtc_dev; spinlock_t lock; /* protecting register access */ unsigned long capabilities; /* See asm/rtc.h for cap bits */};
static irqreturn_t sh_rtc_alarm(int irq, void *dev_id){ struct sh_rtc *rtc = dev_id; unsigned int tmp, pending;
spin_lock(&rtc->lock);
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);
spin_unlock(&rtc->lock);
return IRQ_RETVAL(pending);}
static int sh_rtc_alarm_irq_enable(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);
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
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, .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, *req_res; char clk_name[14]; int clk_id, ret; unsigned int tmp; resource_size_t regsize;
rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL); if (unlikely(!rtc)) return -ENOMEM;
spin_lock_init(&rtc->lock);
ret = platform_get_irq(pdev, 0); if (unlikely(ret <= 0)) { dev_err(&pdev->dev, "No IRQ resource\n"); return -ENOENT; }
if (!pdev->dev.of_node) rtc->alarm_irq = platform_get_irq(pdev, 2); else rtc->alarm_irq = ret;
res = platform_get_resource(pdev, IORESOURCE_IO, 0); if (!res) res = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!res) { dev_err(&pdev->dev, "No IO resource\n"); return -ENOENT; }
regsize = resource_size(res); req_res = devm_request_mem_region(&pdev->dev, res->start, regsize, pdev->name); if (!req_res) return -EBUSY;
rtc->regbase = devm_ioremap(&pdev->dev, req_res->start, regsize); if (!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
ret = devm_request_irq(&pdev->dev, rtc->alarm_irq, sh_rtc_alarm, 0, "sh-rtc", rtc); if (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 */ tmp = readb(rtc->regbase + RCR1); tmp &= ~(RCR1_CIE | RCR1_AIE); writeb(tmp, rtc->regbase + RCR1);
rtc->rtc_dev->ops = &sh_rtc_ops;
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 = devm_rtc_register_device(rtc->rtc_dev); if (ret) goto err_unmap;
device_init_wakeup(&pdev->dev, true); return 0;
err_unmap: clk_disable(rtc->clk);
return ret;}
static void __exit sh_rtc_remove(struct platform_device *pdev){ struct sh_rtc *rtc = platform_get_drvdata(pdev);
sh_rtc_alarm_irq_enable(&pdev->dev, 0);
clk_disable(rtc->clk);}
static int sh_rtc_suspend(struct device *dev){ struct sh_rtc *rtc = dev_get_drvdata(dev);
if (device_may_wakeup(dev)) irq_set_irq_wake(rtc->alarm_irq, 1);
return 0;}
static int sh_rtc_resume(struct device *dev){ struct sh_rtc *rtc = dev_get_drvdata(dev);
if (device_may_wakeup(dev)) irq_set_irq_wake(rtc->alarm_irq, 0);
return 0;}
static DEFINE_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);
/* * sh_rtc_remove() lives in .exit.text. For drivers registered via * module_platform_driver_probe() this is ok because they cannot get unbound at * runtime. So mark the driver struct with __refdata to prevent modpost * triggering a section mismatch warning. */static struct platform_driver sh_rtc_platform_driver __refdata = { .driver = { .name = DRV_NAME, .pm = pm_sleep_ptr(&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>");MODULE_AUTHOR("Jamie Lenehan <lenehan@twibble.org>");MODULE_AUTHOR("Angelo Castello <angelo.castello@st.com>");MODULE_LICENSE("GPL v2");MODULE_ALIAS("platform:" DRV_NAME);