diff options
Diffstat (limited to 'drivers/rtc/rtc-pl031.c')
| -rw-r--r-- | drivers/rtc/rtc-pl031.c | 233 |
1 files changed, 233 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-pl031.c b/drivers/rtc/rtc-pl031.c new file mode 100644 index 000000000000..ee538632660b --- /dev/null +++ b/drivers/rtc/rtc-pl031.c @@ -0,0 +1,233 @@ +/* + * drivers/rtc/rtc-pl031.c + * + * Real Time Clock interface for ARM AMBA PrimeCell 031 RTC + * + * Author: Deepak Saxena <dsaxena@plexity.net> + * + * Copyright 2006 (c) MontaVista Software, Inc. + * + * 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. + */ + +#include <linux/platform_device.h> +#include <linux/module.h> +#include <linux/rtc.h> +#include <linux/init.h> +#include <linux/fs.h> +#include <linux/interrupt.h> +#include <linux/string.h> +#include <linux/pm.h> + +#include <linux/amba/bus.h> + +#include <asm/io.h> +#include <asm/bitops.h> +#include <asm/hardware.h> +#include <asm/irq.h> +#include <asm/rtc.h> + +/* + * Register definitions + */ +#define RTC_DR 0x00 /* Data read register */ +#define RTC_MR 0x04 /* Match register */ +#define RTC_LR 0x08 /* Data load register */ +#define RTC_CR 0x0c /* Control register */ +#define RTC_IMSC 0x10 /* Interrupt mask and set register */ +#define RTC_RIS 0x14 /* Raw interrupt status register */ +#define RTC_MIS 0x18 /* Masked interrupt status register */ +#define RTC_ICR 0x1c /* Interrupt clear register */ + +struct pl031_local { + struct rtc_device *rtc; + void __iomem *base; +}; + +static irqreturn_t pl031_interrupt(int irq, void *dev_id, struct pt_regs *regs) +{ + struct rtc_device *rtc = dev_id; + + rtc_update_irq(&rtc->class_dev, 1, RTC_AF); + + return IRQ_HANDLED; +} + +static int pl031_open(struct device *dev) +{ + /* + * We request IRQ in pl031_probe, so nothing to do here... + */ + return 0; +} + +static void pl031_release(struct device *dev) +{ +} + +static int pl031_ioctl(struct device *dev, unsigned int cmd, unsigned long arg) +{ + struct pl031_local *ldata = dev_get_drvdata(dev); + + switch (cmd) { + case RTC_AIE_OFF: + __raw_writel(1, ldata->base + RTC_MIS); + return 0; + case RTC_AIE_ON: + __raw_writel(0, ldata->base + RTC_MIS); + return 0; + } + + return -ENOIOCTLCMD; +} + +static int pl031_read_time(struct device *dev, struct rtc_time *tm) +{ + struct pl031_local *ldata = dev_get_drvdata(dev); + + rtc_time_to_tm(__raw_readl(ldata->base + RTC_DR), tm); + + return 0; +} + +static int pl031_set_time(struct device *dev, struct rtc_time *tm) +{ + unsigned long time; + struct pl031_local *ldata = dev_get_drvdata(dev); + + rtc_tm_to_time(tm, &time); + __raw_writel(time, ldata->base + RTC_LR); + + return 0; +} + +static int pl031_read_alarm(struct device *dev, struct rtc_wkalrm *alarm) +{ + struct pl031_local *ldata = dev_get_drvdata(dev); + + rtc_time_to_tm(__raw_readl(ldata->base + RTC_MR), &alarm->time); + alarm->pending = __raw_readl(ldata->base + RTC_RIS); + alarm->enabled = __raw_readl(ldata->base + RTC_IMSC); + + return 0; +} + +static int pl031_set_alarm(struct device *dev, struct rtc_wkalrm *alarm) +{ + struct pl031_local *ldata = dev_get_drvdata(dev); + unsigned long time; + + rtc_tm_to_time(&alarm->time, &time); + + __raw_writel(time, ldata->base + RTC_MR); + __raw_writel(!alarm->enabled, ldata->base + RTC_MIS); + + return 0; +} + +static struct rtc_class_ops pl031_ops = { + .open = pl031_open, + .release = pl031_release, + .ioctl = pl031_ioctl, + .read_time = pl031_read_time, + .set_time = pl031_set_time, + .read_alarm = pl031_read_alarm, + .set_alarm = pl031_set_alarm, +}; + +static int pl031_remove(struct amba_device *adev) +{ + struct pl031_local *ldata = dev_get_drvdata(&adev->dev); + + if (ldata) { + dev_set_drvdata(&adev->dev, NULL); + free_irq(adev->irq[0], ldata->rtc); + rtc_device_unregister(ldata->rtc); + iounmap(ldata->base); + kfree(ldata); + } + + return 0; +} + +static int pl031_probe(struct amba_device *adev, void *id) +{ + int ret; + struct pl031_local *ldata; + + + ldata = kmalloc(sizeof(struct pl031_local), GFP_KERNEL); + if (!ldata) { + ret = -ENOMEM; + goto out; + } + dev_set_drvdata(&adev->dev, ldata); + + ldata->base = ioremap(adev->res.start, + adev->res.end - adev->res.start + 1); + if (!ldata->base) { + ret = -ENOMEM; + goto out_no_remap; + } + + if (request_irq(adev->irq[0], pl031_interrupt, SA_INTERRUPT, + "rtc-pl031", ldata->rtc)) { + ret = -EIO; + goto out_no_irq; + } + + ldata->rtc = rtc_device_register("pl031", &adev->dev, &pl031_ops, + THIS_MODULE); + if (IS_ERR(ldata->rtc)) { + ret = PTR_ERR(ldata->rtc); + goto out_no_rtc; + } + + return 0; + +out_no_rtc: + free_irq(adev->irq[0], ldata->rtc); +out_no_irq: + iounmap(ldata->base); +out_no_remap: + dev_set_drvdata(&adev->dev, NULL); + kfree(ldata); +out: + return ret; +} + +static struct amba_id pl031_ids[] __initdata = { + { + .id = 0x00041031, + .mask = 0x000fffff, }, + {0, 0}, +}; + +static struct amba_driver pl031_driver = { + .drv = { + .name = "rtc-pl031", + }, + .id_table = pl031_ids, + .probe = pl031_probe, + .remove = pl031_remove, +}; + +static int __init pl031_init(void) +{ + return amba_driver_register(&pl031_driver); +} + +static void __exit pl031_exit(void) +{ + amba_driver_unregister(&pl031_driver); +} + +module_init(pl031_init); +module_exit(pl031_exit); + +MODULE_AUTHOR("Deepak Saxena <dsaxena@plexity.net"); +MODULE_DESCRIPTION("ARM AMBA PL031 RTC Driver"); +MODULE_LICENSE("GPL"); |