358 lines
9.8 KiB
C
358 lines
9.8 KiB
C
/*
|
|
* Freescale STMP37XX/STMP378X Real Time Clock driver
|
|
*
|
|
* Copyright (c) 2007 Sigmatel, Inc.
|
|
* Peter Hartley, <peter.hartley@sigmatel.com>
|
|
*
|
|
* Copyright 2008 Freescale Semiconductor, Inc. All Rights Reserved.
|
|
* Copyright 2008 Embedded Alley Solutions, Inc All Rights Reserved.
|
|
* Copyright 2011 Wolfram Sang, Pengutronix e.K.
|
|
*/
|
|
|
|
/*
|
|
* The code contained herein is licensed under the GNU General Public
|
|
* License. You may obtain a copy of the GNU General Public License
|
|
* Version 2 or later at the following locations:
|
|
*
|
|
* http://www.opensource.org/licenses/gpl-license.html
|
|
* http://www.gnu.org/copyleft/gpl.html
|
|
*/
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/io.h>
|
|
#include <linux/init.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/rtc.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/of_device.h>
|
|
#include <linux/of.h>
|
|
#include <linux/stmp_device.h>
|
|
#include <linux/stmp3xxx_rtc_wdt.h>
|
|
|
|
#include <mach/common.h>
|
|
|
|
#define STMP3XXX_RTC_CTRL 0x0
|
|
#define STMP3XXX_RTC_CTRL_SET 0x4
|
|
#define STMP3XXX_RTC_CTRL_CLR 0x8
|
|
#define STMP3XXX_RTC_CTRL_ALARM_IRQ_EN 0x00000001
|
|
#define STMP3XXX_RTC_CTRL_ONEMSEC_IRQ_EN 0x00000002
|
|
#define STMP3XXX_RTC_CTRL_ALARM_IRQ 0x00000004
|
|
#define STMP3XXX_RTC_CTRL_WATCHDOGEN 0x00000010
|
|
|
|
#define STMP3XXX_RTC_STAT 0x10
|
|
#define STMP3XXX_RTC_STAT_STALE_SHIFT 16
|
|
#define STMP3XXX_RTC_STAT_RTC_PRESENT 0x80000000
|
|
|
|
#define STMP3XXX_RTC_SECONDS 0x30
|
|
|
|
#define STMP3XXX_RTC_ALARM 0x40
|
|
|
|
#define STMP3XXX_RTC_WATCHDOG 0x50
|
|
|
|
#define STMP3XXX_RTC_PERSISTENT0 0x60
|
|
#define STMP3XXX_RTC_PERSISTENT0_SET 0x64
|
|
#define STMP3XXX_RTC_PERSISTENT0_CLR 0x68
|
|
#define STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN 0x00000002
|
|
#define STMP3XXX_RTC_PERSISTENT0_ALARM_EN 0x00000004
|
|
#define STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE 0x00000080
|
|
|
|
#define STMP3XXX_RTC_PERSISTENT1 0x70
|
|
/* missing bitmask in headers */
|
|
#define STMP3XXX_RTC_PERSISTENT1_FORCE_UPDATER 0x80000000
|
|
|
|
struct stmp3xxx_rtc_data {
|
|
struct rtc_device *rtc;
|
|
void __iomem *io;
|
|
int irq_alarm;
|
|
};
|
|
|
|
#if IS_ENABLED(CONFIG_STMP3XXX_RTC_WATCHDOG)
|
|
/**
|
|
* stmp3xxx_wdt_set_timeout - configure the watchdog inside the STMP3xxx RTC
|
|
* @dev: the parent device of the watchdog (= the RTC)
|
|
* @timeout: the desired value for the timeout register of the watchdog.
|
|
* 0 disables the watchdog
|
|
*
|
|
* The watchdog needs one register and two bits which are in the RTC domain.
|
|
* To handle the resource conflict, the RTC driver will create another
|
|
* platform_device for the watchdog driver as a child of the RTC device.
|
|
* The watchdog driver is passed the below accessor function via platform_data
|
|
* to configure the watchdog. Locking is not needed because accessing SET/CLR
|
|
* registers is atomic.
|
|
*/
|
|
|
|
static void stmp3xxx_wdt_set_timeout(struct device *dev, u32 timeout)
|
|
{
|
|
struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
|
|
|
|
if (timeout) {
|
|
writel(timeout, rtc_data->io + STMP3XXX_RTC_WATCHDOG);
|
|
writel(STMP3XXX_RTC_CTRL_WATCHDOGEN,
|
|
rtc_data->io + STMP3XXX_RTC_CTRL + STMP_OFFSET_REG_SET);
|
|
writel(STMP3XXX_RTC_PERSISTENT1_FORCE_UPDATER,
|
|
rtc_data->io + STMP3XXX_RTC_PERSISTENT1 + STMP_OFFSET_REG_SET);
|
|
} else {
|
|
writel(STMP3XXX_RTC_CTRL_WATCHDOGEN,
|
|
rtc_data->io + STMP3XXX_RTC_CTRL + STMP_OFFSET_REG_CLR);
|
|
writel(STMP3XXX_RTC_PERSISTENT1_FORCE_UPDATER,
|
|
rtc_data->io + STMP3XXX_RTC_PERSISTENT1 + STMP_OFFSET_REG_CLR);
|
|
}
|
|
}
|
|
|
|
static struct stmp3xxx_wdt_pdata wdt_pdata = {
|
|
.wdt_set_timeout = stmp3xxx_wdt_set_timeout,
|
|
};
|
|
|
|
static void stmp3xxx_wdt_register(struct platform_device *rtc_pdev)
|
|
{
|
|
struct platform_device *wdt_pdev =
|
|
platform_device_alloc("stmp3xxx_rtc_wdt", rtc_pdev->id);
|
|
|
|
if (wdt_pdev) {
|
|
wdt_pdev->dev.parent = &rtc_pdev->dev;
|
|
wdt_pdev->dev.platform_data = &wdt_pdata;
|
|
platform_device_add(wdt_pdev);
|
|
}
|
|
}
|
|
#else
|
|
static void stmp3xxx_wdt_register(struct platform_device *rtc_pdev)
|
|
{
|
|
}
|
|
#endif /* CONFIG_STMP3XXX_RTC_WATCHDOG */
|
|
|
|
static void stmp3xxx_wait_time(struct stmp3xxx_rtc_data *rtc_data)
|
|
{
|
|
/*
|
|
* The datasheet doesn't say which way round the
|
|
* NEW_REGS/STALE_REGS bitfields go. In fact it's 0x1=P0,
|
|
* 0x2=P1, .., 0x20=P5, 0x40=ALARM, 0x80=SECONDS
|
|
*/
|
|
while (readl(rtc_data->io + STMP3XXX_RTC_STAT) &
|
|
(0x80 << STMP3XXX_RTC_STAT_STALE_SHIFT))
|
|
cpu_relax();
|
|
}
|
|
|
|
/* Time read/write */
|
|
static int stmp3xxx_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)
|
|
{
|
|
struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
|
|
|
|
stmp3xxx_wait_time(rtc_data);
|
|
rtc_time_to_tm(readl(rtc_data->io + STMP3XXX_RTC_SECONDS), rtc_tm);
|
|
return 0;
|
|
}
|
|
|
|
static int stmp3xxx_rtc_set_mmss(struct device *dev, unsigned long t)
|
|
{
|
|
struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
|
|
|
|
writel(t, rtc_data->io + STMP3XXX_RTC_SECONDS);
|
|
stmp3xxx_wait_time(rtc_data);
|
|
return 0;
|
|
}
|
|
|
|
/* interrupt(s) handler */
|
|
static irqreturn_t stmp3xxx_rtc_interrupt(int irq, void *dev_id)
|
|
{
|
|
struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev_id);
|
|
u32 status = readl(rtc_data->io + STMP3XXX_RTC_CTRL);
|
|
|
|
if (status & STMP3XXX_RTC_CTRL_ALARM_IRQ) {
|
|
writel(STMP3XXX_RTC_CTRL_ALARM_IRQ,
|
|
rtc_data->io + STMP3XXX_RTC_CTRL_CLR);
|
|
rtc_update_irq(rtc_data->rtc, 1, RTC_AF | RTC_IRQF);
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
return IRQ_NONE;
|
|
}
|
|
|
|
static int stmp3xxx_alarm_irq_enable(struct device *dev, unsigned int enabled)
|
|
{
|
|
struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
|
|
|
|
if (enabled) {
|
|
writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN |
|
|
STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN,
|
|
rtc_data->io + STMP3XXX_RTC_PERSISTENT0_SET);
|
|
writel(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN,
|
|
rtc_data->io + STMP3XXX_RTC_CTRL_SET);
|
|
} else {
|
|
writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN |
|
|
STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN,
|
|
rtc_data->io + STMP3XXX_RTC_PERSISTENT0_CLR);
|
|
writel(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN,
|
|
rtc_data->io + STMP3XXX_RTC_CTRL_CLR);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int stmp3xxx_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
|
|
{
|
|
struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
|
|
|
|
rtc_time_to_tm(readl(rtc_data->io + STMP3XXX_RTC_ALARM), &alm->time);
|
|
return 0;
|
|
}
|
|
|
|
static int stmp3xxx_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
|
|
{
|
|
unsigned long t;
|
|
struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
|
|
|
|
rtc_tm_to_time(&alm->time, &t);
|
|
writel(t, rtc_data->io + STMP3XXX_RTC_ALARM);
|
|
|
|
stmp3xxx_alarm_irq_enable(dev, alm->enabled);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct rtc_class_ops stmp3xxx_rtc_ops = {
|
|
.alarm_irq_enable =
|
|
stmp3xxx_alarm_irq_enable,
|
|
.read_time = stmp3xxx_rtc_gettime,
|
|
.set_mmss = stmp3xxx_rtc_set_mmss,
|
|
.read_alarm = stmp3xxx_rtc_read_alarm,
|
|
.set_alarm = stmp3xxx_rtc_set_alarm,
|
|
};
|
|
|
|
static int stmp3xxx_rtc_remove(struct platform_device *pdev)
|
|
{
|
|
struct stmp3xxx_rtc_data *rtc_data = platform_get_drvdata(pdev);
|
|
|
|
if (!rtc_data)
|
|
return 0;
|
|
|
|
writel(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN,
|
|
rtc_data->io + STMP3XXX_RTC_CTRL_CLR);
|
|
free_irq(rtc_data->irq_alarm, &pdev->dev);
|
|
rtc_device_unregister(rtc_data->rtc);
|
|
platform_set_drvdata(pdev, NULL);
|
|
iounmap(rtc_data->io);
|
|
kfree(rtc_data);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int stmp3xxx_rtc_probe(struct platform_device *pdev)
|
|
{
|
|
struct stmp3xxx_rtc_data *rtc_data;
|
|
struct resource *r;
|
|
int err;
|
|
|
|
rtc_data = kzalloc(sizeof *rtc_data, GFP_KERNEL);
|
|
if (!rtc_data)
|
|
return -ENOMEM;
|
|
|
|
r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
|
if (!r) {
|
|
dev_err(&pdev->dev, "failed to get resource\n");
|
|
err = -ENXIO;
|
|
goto out_free;
|
|
}
|
|
|
|
rtc_data->io = ioremap(r->start, resource_size(r));
|
|
if (!rtc_data->io) {
|
|
dev_err(&pdev->dev, "ioremap failed\n");
|
|
err = -EIO;
|
|
goto out_free;
|
|
}
|
|
|
|
rtc_data->irq_alarm = platform_get_irq(pdev, 0);
|
|
|
|
if (!(readl(STMP3XXX_RTC_STAT + rtc_data->io) &
|
|
STMP3XXX_RTC_STAT_RTC_PRESENT)) {
|
|
dev_err(&pdev->dev, "no device onboard\n");
|
|
err = -ENODEV;
|
|
goto out_remap;
|
|
}
|
|
|
|
platform_set_drvdata(pdev, rtc_data);
|
|
|
|
mxs_reset_block(rtc_data->io);
|
|
writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN |
|
|
STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN |
|
|
STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE,
|
|
rtc_data->io + STMP3XXX_RTC_PERSISTENT0_CLR);
|
|
|
|
writel(STMP3XXX_RTC_CTRL_ONEMSEC_IRQ_EN |
|
|
STMP3XXX_RTC_CTRL_ALARM_IRQ_EN,
|
|
rtc_data->io + STMP3XXX_RTC_CTRL_CLR);
|
|
|
|
rtc_data->rtc = rtc_device_register(pdev->name, &pdev->dev,
|
|
&stmp3xxx_rtc_ops, THIS_MODULE);
|
|
if (IS_ERR(rtc_data->rtc)) {
|
|
err = PTR_ERR(rtc_data->rtc);
|
|
goto out_remap;
|
|
}
|
|
|
|
err = request_irq(rtc_data->irq_alarm, stmp3xxx_rtc_interrupt, 0,
|
|
"RTC alarm", &pdev->dev);
|
|
if (err) {
|
|
dev_err(&pdev->dev, "Cannot claim IRQ%d\n",
|
|
rtc_data->irq_alarm);
|
|
goto out_irq_alarm;
|
|
}
|
|
|
|
stmp3xxx_wdt_register(pdev);
|
|
return 0;
|
|
|
|
out_irq_alarm:
|
|
rtc_device_unregister(rtc_data->rtc);
|
|
out_remap:
|
|
platform_set_drvdata(pdev, NULL);
|
|
iounmap(rtc_data->io);
|
|
out_free:
|
|
kfree(rtc_data);
|
|
return err;
|
|
}
|
|
|
|
#ifdef CONFIG_PM
|
|
static int stmp3xxx_rtc_suspend(struct platform_device *dev, pm_message_t state)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static int stmp3xxx_rtc_resume(struct platform_device *dev)
|
|
{
|
|
struct stmp3xxx_rtc_data *rtc_data = platform_get_drvdata(dev);
|
|
|
|
mxs_reset_block(rtc_data->io);
|
|
writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN |
|
|
STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN |
|
|
STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE,
|
|
rtc_data->io + STMP3XXX_RTC_PERSISTENT0_CLR);
|
|
return 0;
|
|
}
|
|
#else
|
|
#define stmp3xxx_rtc_suspend NULL
|
|
#define stmp3xxx_rtc_resume NULL
|
|
#endif
|
|
|
|
static const struct of_device_id rtc_dt_ids[] = {
|
|
{ .compatible = "fsl,stmp3xxx-rtc", },
|
|
{ /* sentinel */ }
|
|
};
|
|
MODULE_DEVICE_TABLE(of, rtc_dt_ids);
|
|
|
|
static struct platform_driver stmp3xxx_rtcdrv = {
|
|
.probe = stmp3xxx_rtc_probe,
|
|
.remove = stmp3xxx_rtc_remove,
|
|
.suspend = stmp3xxx_rtc_suspend,
|
|
.resume = stmp3xxx_rtc_resume,
|
|
.driver = {
|
|
.name = "stmp3xxx-rtc",
|
|
.owner = THIS_MODULE,
|
|
.of_match_table = of_match_ptr(rtc_dt_ids),
|
|
},
|
|
};
|
|
|
|
module_platform_driver(stmp3xxx_rtcdrv);
|
|
|
|
MODULE_DESCRIPTION("STMP3xxx RTC Driver");
|
|
MODULE_AUTHOR("dmitry pervushin <dpervushin@embeddedalley.com> and "
|
|
"Wolfram Sang <w.sang@pengutronix.de>");
|
|
MODULE_LICENSE("GPL");
|