diff options
Diffstat (limited to 'drivers/rtc/rtc-pxa.c')
| -rw-r--r-- | drivers/rtc/rtc-pxa.c | 453 |
1 files changed, 453 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-pxa.c b/drivers/rtc/rtc-pxa.c new file mode 100644 index 00000000..0075c8fd --- /dev/null +++ b/drivers/rtc/rtc-pxa.c @@ -0,0 +1,453 @@ +/* + * Real Time Clock interface for XScale PXA27x and PXA3xx + * + * Copyright (C) 2008 Robert Jarzmik + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * 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. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + */ + +#include <linux/init.h> +#include <linux/platform_device.h> +#include <linux/module.h> +#include <linux/rtc.h> +#include <linux/seq_file.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/slab.h> + +#include <mach/hardware.h> + +#define TIMER_FREQ CLOCK_TICK_RATE +#define RTC_DEF_DIVIDER (32768 - 1) +#define RTC_DEF_TRIM 0 +#define MAXFREQ_PERIODIC 1000 + +/* + * PXA Registers and bits definitions + */ +#define RTSR_PICE (1 << 15) /* Periodic interrupt count enable */ +#define RTSR_PIALE (1 << 14) /* Periodic interrupt Alarm enable */ +#define RTSR_PIAL (1 << 13) /* Periodic interrupt detected */ +#define RTSR_SWALE2 (1 << 11) /* RTC stopwatch alarm2 enable */ +#define RTSR_SWAL2 (1 << 10) /* RTC stopwatch alarm2 detected */ +#define RTSR_SWALE1 (1 << 9) /* RTC stopwatch alarm1 enable */ +#define RTSR_SWAL1 (1 << 8) /* RTC stopwatch alarm1 detected */ +#define RTSR_RDALE2 (1 << 7) /* RTC alarm2 enable */ +#define RTSR_RDAL2 (1 << 6) /* RTC alarm2 detected */ +#define RTSR_RDALE1 (1 << 5) /* RTC alarm1 enable */ +#define RTSR_RDAL1 (1 << 4) /* RTC alarm1 detected */ +#define RTSR_HZE (1 << 3) /* HZ interrupt enable */ +#define RTSR_ALE (1 << 2) /* RTC alarm interrupt enable */ +#define RTSR_HZ (1 << 1) /* HZ rising-edge detected */ +#define RTSR_AL (1 << 0) /* RTC alarm detected */ +#define RTSR_TRIG_MASK (RTSR_AL | RTSR_HZ | RTSR_RDAL1 | RTSR_RDAL2\ + | RTSR_SWAL1 | RTSR_SWAL2) +#define RYxR_YEAR_S 9 +#define RYxR_YEAR_MASK (0xfff << RYxR_YEAR_S) +#define RYxR_MONTH_S 5 +#define RYxR_MONTH_MASK (0xf << RYxR_MONTH_S) +#define RYxR_DAY_MASK 0x1f +#define RDxR_HOUR_S 12 +#define RDxR_HOUR_MASK (0x1f << RDxR_HOUR_S) +#define RDxR_MIN_S 6 +#define RDxR_MIN_MASK (0x3f << RDxR_MIN_S) +#define RDxR_SEC_MASK 0x3f + +#define RTSR 0x08 +#define RTTR 0x0c +#define RDCR 0x10 +#define RYCR 0x14 +#define RDAR1 0x18 +#define RYAR1 0x1c +#define RTCPICR 0x34 +#define PIAR 0x38 + +#define rtc_readl(pxa_rtc, reg) \ + __raw_readl((pxa_rtc)->base + (reg)) +#define rtc_writel(pxa_rtc, reg, value) \ + __raw_writel((value), (pxa_rtc)->base + (reg)) + +struct pxa_rtc { + struct resource *ress; + void __iomem *base; + int irq_1Hz; + int irq_Alrm; + struct rtc_device *rtc; + spinlock_t lock; /* Protects this structure */ +}; + +static u32 ryxr_calc(struct rtc_time *tm) +{ + return ((tm->tm_year + 1900) << RYxR_YEAR_S) + | ((tm->tm_mon + 1) << RYxR_MONTH_S) + | tm->tm_mday; +} + +static u32 rdxr_calc(struct rtc_time *tm) +{ + return (tm->tm_hour << RDxR_HOUR_S) | (tm->tm_min << RDxR_MIN_S) + | tm->tm_sec; +} + +static void tm_calc(u32 rycr, u32 rdcr, struct rtc_time *tm) +{ + tm->tm_year = ((rycr & RYxR_YEAR_MASK) >> RYxR_YEAR_S) - 1900; + tm->tm_mon = (((rycr & RYxR_MONTH_MASK) >> RYxR_MONTH_S)) - 1; + tm->tm_mday = (rycr & RYxR_DAY_MASK); + tm->tm_hour = (rdcr & RDxR_HOUR_MASK) >> RDxR_HOUR_S; + tm->tm_min = (rdcr & RDxR_MIN_MASK) >> RDxR_MIN_S; + tm->tm_sec = rdcr & RDxR_SEC_MASK; +} + +static void rtsr_clear_bits(struct pxa_rtc *pxa_rtc, u32 mask) +{ + u32 rtsr; + + rtsr = rtc_readl(pxa_rtc, RTSR); + rtsr &= ~RTSR_TRIG_MASK; + rtsr &= ~mask; + rtc_writel(pxa_rtc, RTSR, rtsr); +} + +static void rtsr_set_bits(struct pxa_rtc *pxa_rtc, u32 mask) +{ + u32 rtsr; + + rtsr = rtc_readl(pxa_rtc, RTSR); + rtsr &= ~RTSR_TRIG_MASK; + rtsr |= mask; + rtc_writel(pxa_rtc, RTSR, rtsr); +} + +static irqreturn_t pxa_rtc_irq(int irq, void *dev_id) +{ + struct platform_device *pdev = to_platform_device(dev_id); + struct pxa_rtc *pxa_rtc = platform_get_drvdata(pdev); + u32 rtsr; + unsigned long events = 0; + + spin_lock(&pxa_rtc->lock); + + /* clear interrupt sources */ + rtsr = rtc_readl(pxa_rtc, RTSR); + rtc_writel(pxa_rtc, RTSR, rtsr); + + /* temporary disable rtc interrupts */ + rtsr_clear_bits(pxa_rtc, RTSR_RDALE1 | RTSR_PIALE | RTSR_HZE); + + /* clear alarm interrupt if it has occurred */ + if (rtsr & RTSR_RDAL1) + rtsr &= ~RTSR_RDALE1; + + /* update irq data & counter */ + if (rtsr & RTSR_RDAL1) + events |= RTC_AF | RTC_IRQF; + if (rtsr & RTSR_HZ) + events |= RTC_UF | RTC_IRQF; + if (rtsr & RTSR_PIAL) + events |= RTC_PF | RTC_IRQF; + + rtc_update_irq(pxa_rtc->rtc, 1, events); + + /* enable back rtc interrupts */ + rtc_writel(pxa_rtc, RTSR, rtsr & ~RTSR_TRIG_MASK); + + spin_unlock(&pxa_rtc->lock); + return IRQ_HANDLED; +} + +static int pxa_rtc_open(struct device *dev) +{ + struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev); + int ret; + + ret = request_irq(pxa_rtc->irq_1Hz, pxa_rtc_irq, 0, + "rtc 1Hz", dev); + if (ret < 0) { + dev_err(dev, "can't get irq %i, err %d\n", pxa_rtc->irq_1Hz, + ret); + goto err_irq_1Hz; + } + ret = request_irq(pxa_rtc->irq_Alrm, pxa_rtc_irq, 0, + "rtc Alrm", dev); + if (ret < 0) { + dev_err(dev, "can't get irq %i, err %d\n", pxa_rtc->irq_Alrm, + ret); + goto err_irq_Alrm; + } + + return 0; + +err_irq_Alrm: + free_irq(pxa_rtc->irq_1Hz, dev); +err_irq_1Hz: + return ret; +} + +static void pxa_rtc_release(struct device *dev) +{ + struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev); + + spin_lock_irq(&pxa_rtc->lock); + rtsr_clear_bits(pxa_rtc, RTSR_PIALE | RTSR_RDALE1 | RTSR_HZE); + spin_unlock_irq(&pxa_rtc->lock); + + free_irq(pxa_rtc->irq_Alrm, dev); + free_irq(pxa_rtc->irq_1Hz, dev); +} + +static int pxa_alarm_irq_enable(struct device *dev, unsigned int enabled) +{ + struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev); + + spin_lock_irq(&pxa_rtc->lock); + + if (enabled) + rtsr_set_bits(pxa_rtc, RTSR_RDALE1); + else + rtsr_clear_bits(pxa_rtc, RTSR_RDALE1); + + spin_unlock_irq(&pxa_rtc->lock); + return 0; +} + +static int pxa_rtc_read_time(struct device *dev, struct rtc_time *tm) +{ + struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev); + u32 rycr, rdcr; + + rycr = rtc_readl(pxa_rtc, RYCR); + rdcr = rtc_readl(pxa_rtc, RDCR); + + tm_calc(rycr, rdcr, tm); + return 0; +} + +static int pxa_rtc_set_time(struct device *dev, struct rtc_time *tm) +{ + struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev); + + rtc_writel(pxa_rtc, RYCR, ryxr_calc(tm)); + rtc_writel(pxa_rtc, RDCR, rdxr_calc(tm)); + + return 0; +} + +static int pxa_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev); + u32 rtsr, ryar, rdar; + + ryar = rtc_readl(pxa_rtc, RYAR1); + rdar = rtc_readl(pxa_rtc, RDAR1); + tm_calc(ryar, rdar, &alrm->time); + + rtsr = rtc_readl(pxa_rtc, RTSR); + alrm->enabled = (rtsr & RTSR_RDALE1) ? 1 : 0; + alrm->pending = (rtsr & RTSR_RDAL1) ? 1 : 0; + return 0; +} + +static int pxa_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev); + u32 rtsr; + + spin_lock_irq(&pxa_rtc->lock); + + rtc_writel(pxa_rtc, RYAR1, ryxr_calc(&alrm->time)); + rtc_writel(pxa_rtc, RDAR1, rdxr_calc(&alrm->time)); + + rtsr = rtc_readl(pxa_rtc, RTSR); + if (alrm->enabled) + rtsr |= RTSR_RDALE1; + else + rtsr &= ~RTSR_RDALE1; + rtc_writel(pxa_rtc, RTSR, rtsr); + + spin_unlock_irq(&pxa_rtc->lock); + + return 0; +} + +static int pxa_rtc_proc(struct device *dev, struct seq_file *seq) +{ + struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev); + + seq_printf(seq, "trim/divider\t: 0x%08x\n", rtc_readl(pxa_rtc, RTTR)); + seq_printf(seq, "update_IRQ\t: %s\n", + (rtc_readl(pxa_rtc, RTSR) & RTSR_HZE) ? "yes" : "no"); + seq_printf(seq, "periodic_IRQ\t: %s\n", + (rtc_readl(pxa_rtc, RTSR) & RTSR_PIALE) ? "yes" : "no"); + seq_printf(seq, "periodic_freq\t: %u\n", rtc_readl(pxa_rtc, PIAR)); + + return 0; +} + +static const struct rtc_class_ops pxa_rtc_ops = { + .open = pxa_rtc_open, + .release = pxa_rtc_release, + .read_time = pxa_rtc_read_time, + .set_time = pxa_rtc_set_time, + .read_alarm = pxa_rtc_read_alarm, + .set_alarm = pxa_rtc_set_alarm, + .alarm_irq_enable = pxa_alarm_irq_enable, + .proc = pxa_rtc_proc, +}; + +static int __init pxa_rtc_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct pxa_rtc *pxa_rtc; + int ret; + u32 rttr; + + pxa_rtc = kzalloc(sizeof(struct pxa_rtc), GFP_KERNEL); + if (!pxa_rtc) + return -ENOMEM; + + spin_lock_init(&pxa_rtc->lock); + platform_set_drvdata(pdev, pxa_rtc); + + ret = -ENXIO; + pxa_rtc->ress = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!pxa_rtc->ress) { + dev_err(dev, "No I/O memory resource defined\n"); + goto err_ress; + } + + pxa_rtc->irq_1Hz = platform_get_irq(pdev, 0); + if (pxa_rtc->irq_1Hz < 0) { + dev_err(dev, "No 1Hz IRQ resource defined\n"); + goto err_ress; + } + pxa_rtc->irq_Alrm = platform_get_irq(pdev, 1); + if (pxa_rtc->irq_Alrm < 0) { + dev_err(dev, "No alarm IRQ resource defined\n"); + goto err_ress; + } + + ret = -ENOMEM; + pxa_rtc->base = ioremap(pxa_rtc->ress->start, + resource_size(pxa_rtc->ress)); + if (!pxa_rtc->base) { + dev_err(&pdev->dev, "Unable to map pxa RTC I/O memory\n"); + goto err_map; + } + + /* + * If the clock divider is uninitialized then reset it to the + * default value to get the 1Hz clock. + */ + if (rtc_readl(pxa_rtc, RTTR) == 0) { + rttr = RTC_DEF_DIVIDER + (RTC_DEF_TRIM << 16); + rtc_writel(pxa_rtc, RTTR, rttr); + dev_warn(dev, "warning: initializing default clock" + " divider/trim value\n"); + } + + rtsr_clear_bits(pxa_rtc, RTSR_PIALE | RTSR_RDALE1 | RTSR_HZE); + + pxa_rtc->rtc = rtc_device_register("pxa-rtc", &pdev->dev, &pxa_rtc_ops, + THIS_MODULE); + ret = PTR_ERR(pxa_rtc->rtc); + if (IS_ERR(pxa_rtc->rtc)) { + dev_err(dev, "Failed to register RTC device -> %d\n", ret); + goto err_rtc_reg; + } + + device_init_wakeup(dev, 1); + + return 0; + +err_rtc_reg: + iounmap(pxa_rtc->base); +err_ress: +err_map: + kfree(pxa_rtc); + return ret; +} + +static int __exit pxa_rtc_remove(struct platform_device *pdev) +{ + struct pxa_rtc *pxa_rtc = platform_get_drvdata(pdev); + + rtc_device_unregister(pxa_rtc->rtc); + + spin_lock_irq(&pxa_rtc->lock); + iounmap(pxa_rtc->base); + spin_unlock_irq(&pxa_rtc->lock); + + kfree(pxa_rtc); + + return 0; +} + +#ifdef CONFIG_PM +static int pxa_rtc_suspend(struct device *dev) +{ + struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev); + + if (device_may_wakeup(dev)) + enable_irq_wake(pxa_rtc->irq_Alrm); + return 0; +} + +static int pxa_rtc_resume(struct device *dev) +{ + struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev); + + if (device_may_wakeup(dev)) + disable_irq_wake(pxa_rtc->irq_Alrm); + return 0; +} + +static const struct dev_pm_ops pxa_rtc_pm_ops = { + .suspend = pxa_rtc_suspend, + .resume = pxa_rtc_resume, +}; +#endif + +static struct platform_driver pxa_rtc_driver = { + .remove = __exit_p(pxa_rtc_remove), + .driver = { + .name = "pxa-rtc", +#ifdef CONFIG_PM + .pm = &pxa_rtc_pm_ops, +#endif + }, +}; + +static int __init pxa_rtc_init(void) +{ + if (cpu_is_pxa27x() || cpu_is_pxa3xx()) + return platform_driver_probe(&pxa_rtc_driver, pxa_rtc_probe); + + return -ENODEV; +} + +static void __exit pxa_rtc_exit(void) +{ + platform_driver_unregister(&pxa_rtc_driver); +} + +module_init(pxa_rtc_init); +module_exit(pxa_rtc_exit); + +MODULE_AUTHOR("Robert Jarzmik <robert.jarzmik@free.fr>"); +MODULE_DESCRIPTION("PXA27x/PXA3xx Realtime Clock Driver (RTC)"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:pxa-rtc"); |