175 lines
3.5 KiB
C
175 lines
3.5 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/*
|
|
* linux/drivers/rtc/rtc-pl030.c
|
|
*
|
|
* Copyright (C) 2000-2001 Deep Blue Solutions Ltd.
|
|
*/
|
|
#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_time64_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);
|
|
|
|
writel(rtc_tm_to_time64(&alrm->time), rtc->base + RTC_MR);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int pl030_read_time(struct device *dev, struct rtc_time *tm)
|
|
{
|
|
struct pl030_rtc *rtc = dev_get_drvdata(dev);
|
|
|
|
rtc_time64_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);
|
|
|
|
writel(rtc_tm_to_time64(tm) + 1, rtc->base + RTC_LR);
|
|
|
|
return 0;
|
|
}
|
|
|
|
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->rtc->range_max = U32_MAX;
|
|
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 = devm_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 void 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);
|
|
}
|
|
|
|
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");
|