/*
* A driver for the RTC embedded in the Cirrus Logic EP93XX processors
* Copyright (c) 2006 Tower Technologies
*
* Author: Alessandro Zummo <a.zummo@towertech.it>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/module.h>
#include <linux/rtc.h>
#include <linux/platform_device.h>
#include <mach/hardware.h>
#define EP93XX_RTC_REG(x) (EP93XX_RTC_BASE + (x))
#define EP93XX_RTC_DATA EP93XX_RTC_REG(0x0000)
#define EP93XX_RTC_LOAD EP93XX_RTC_REG(0x000C)
#define EP93XX_RTC_SWCOMP EP93XX_RTC_REG(0x0108)
#define DRV_VERSION "0.2"
static int ep93xx_get_swcomp(struct device *dev, unsigned short *preload,
unsigned short *delete)
{
unsigned short comp = __raw_readl(EP93XX_RTC_SWCOMP);
if (preload)
*preload = comp & 0xffff;
if (delete)
*delete = (comp >> 16) & 0x1f;
return 0;
}
static int ep93xx_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
unsigned long time = __raw_readl(EP93XX_RTC_DATA);
rtc_time_to_tm(time, tm);
return 0;
}
static int ep93xx_rtc_set_mmss(struct device *dev, unsigned long secs)
{
__raw_writel(secs + 1, EP93XX_RTC_LOAD);
return 0;
}
static int ep93xx_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
int err;
unsigned long secs;
err = rtc_tm_to_time(tm, &secs);
if (err != 0)
return err;
return ep93xx_rtc_set_mmss(dev, secs);
}
static int ep93xx_rtc_proc(struct device *dev, struct seq_file *seq)
{
unsigned short preload, delete;
ep93xx_get_swcomp(dev, &preload, &delete);
seq_printf(seq, "preload\t\t: %d\n", preload);
seq_printf(seq, "delete\t\t: %d\n", delete);
return 0;
}
static const struct rtc_class_ops ep93xx_rtc_ops = {
.read_time = ep93xx_rtc_read_time,
.set_time = ep93xx_rtc_set_time,
.set_mmss = ep93xx_rtc_set_mmss,
.proc = ep93xx_rtc_proc,
};
static ssize_t ep93xx_sysfs_show_comp_preload(struct device *dev,
struct device_attribute *attr, char *buf)
{
unsigned short preload;
ep93xx_get_swcomp(dev, &preload, NULL);
return sprintf(buf, "%d\n", preload);
}
static DEVICE_ATTR(comp_preload, S_IRUGO, ep93xx_sysfs_show_comp_preload, NULL);
static ssize_t ep93xx_sysfs_show_comp_delete(struct device *dev,
struct device_attribute *attr, char *buf)
{
unsigned short delete;
ep93xx_get_swcomp(dev, NULL, &delete);
return sprintf(buf, "%d\n", delete);
}
static DEVICE_ATTR(comp_delete, S_IRUGO, ep93xx_sysfs_show_comp_delete, NULL);
static int __devinit ep93xx_rtc_probe(struct platform_device *dev)
{
struct rtc_device *rtc = rtc_device_register("ep93xx",
&dev->dev, &ep93xx_rtc_ops, THIS_MODULE);
if (IS_ERR(rtc)) {
return PTR_ERR(rtc);
}
platform_set_drvdata(dev, rtc);
device_create_file(&dev->dev, &dev_attr_comp_preload);
device_create_file(&dev->dev, &dev_attr_comp_delete);
return 0;
}
static int __devexit ep93xx_rtc_remove(struct platform_device *dev)
{
struct rtc_device *rtc = platform_get_drvdata(dev);
if (rtc)
rtc_device_unregister(rtc);
platform_set_drvdata(dev, NULL);
return 0;
}
/* work with hotplug and coldplug */
MODULE_ALIAS("platform:ep93xx-rtc");
static struct platform_driver ep93xx_rtc_platform_driver = {
.driver = {
.name = "ep93xx-rtc",
.owner = THIS_MODULE,
},
.probe = ep93xx_rtc_probe,
.remove = __devexit_p(ep93xx_rtc_remove),
};
static int __init ep93xx_rtc_init(void)
{
return platform_driver_register(&ep93xx_rtc_platform_driver);
}
static void __exit ep93xx_rtc_exit(void)
{
platform_driver_unregister(&ep93xx_rtc_platform_driver);
}
MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
MODULE_DESCRIPTION("EP93XX RTC driver");
MODULE_LICENSE("GPL");
MODULE_VERSION(DRV_VERSION);
module_init(ep93xx_rtc_init);
module_exit(ep93xx_rtc_exit);
