/*
* 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 <linux/io.h>
#include <linux/gfp.h>
#define EP93XX_RTC_DATA 0x000
#define EP93XX_RTC_MATCH 0x004
#define EP93XX_RTC_STATUS 0x008
#define EP93XX_RTC_STATUS_INTR (1<<0)
#define EP93XX_RTC_LOAD 0x00C
#define EP93XX_RTC_CONTROL 0x010
#define EP93XX_RTC_CONTROL_MIE (1<<0)
#define EP93XX_RTC_SWCOMP 0x108
#define EP93XX_RTC_SWCOMP_DEL_MASK 0x001f0000
#define EP93XX_RTC_SWCOMP_DEL_SHIFT 16
#define EP93XX_RTC_SWCOMP_INT_MASK 0x0000ffff
#define EP93XX_RTC_SWCOMP_INT_SHIFT 0
/*
* struct device dev.platform_data is used to store our private data
* because struct rtc_device does not have a variable to hold it.
*/
struct ep93xx_rtc {
void __iomem *mmio_base;
struct rtc_device *rtc;
};
static int ep93xx_rtc_get_swcomp(struct device *dev, unsigned short *preload,
unsigned short *delete)
{
struct ep93xx_rtc *ep93xx_rtc = dev_get_platdata(dev);
unsigned long comp;
comp = readl(ep93xx_rtc->mmio_base + EP93XX_RTC_SWCOMP);
if (preload)
*preload = (comp & EP93XX_RTC_SWCOMP_INT_MASK)
>> EP93XX_RTC_SWCOMP_INT_SHIFT;
if (delete)
*delete = (comp & EP93XX_RTC_SWCOMP_DEL_MASK)
>> EP93XX_RTC_SWCOMP_DEL_SHIFT;
return 0;
}
static int ep93xx_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
struct ep93xx_rtc *ep93xx_rtc = dev_get_platdata(dev);
unsigned long time;
time = readl(ep93xx_rtc->mmio_base + EP93XX_RTC_DATA);
rtc_time_to_tm(time, tm);
return 0;
}
static int ep93xx_rtc_set_mmss(struct device *dev, unsigned long secs)
{
struct ep93xx_rtc *ep93xx_rtc = dev_get_platdata(dev);
writel(secs + 1, ep93xx_rtc->mmio_base + EP93XX_RTC_LOAD);
return 0;
}
static int ep93xx_rtc_proc(struct device *dev, struct seq_file *seq)
{
unsigned short preload, delete;
ep93xx_rtc_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_mmss = ep93xx_rtc_set_mmss,
.proc = ep93xx_rtc_proc,
};
static ssize_t ep93xx_rtc_show_comp_preload(struct device *dev,
struct device_attribute *attr, char *buf)
{
unsigned short preload;
ep93xx_rtc_get_swcomp(dev, &preload, NULL);
return sprintf(buf, "%d\n", preload);
}
static DEVICE_ATTR(comp_preload, S_IRUGO, ep93xx_rtc_show_comp_preload, NULL);
static ssize_t ep93xx_rtc_show_comp_delete(struct device *dev,
struct device_attribute *attr, char *buf)
{
unsigned short delete;
ep93xx_rtc_get_swcomp(dev, NULL, &delete);
return sprintf(buf, "%d\n", delete);
}
static DEVICE_ATTR(comp_delete, S_IRUGO, ep93xx_rtc_show_comp_delete, NULL);
static struct attribute *ep93xx_rtc_attrs[] = {
&dev_attr_comp_preload.attr,
&dev_attr_comp_delete.attr,
NULL
};
static const struct attribute_group ep93xx_rtc_sysfs_files = {
.attrs = ep93xx_rtc_attrs,
};
static int ep93xx_rtc_probe(struct platform_device *pdev)
{
struct ep93xx_rtc *ep93xx_rtc;
struct resource *res;
int err;
ep93xx_rtc = devm_kzalloc(&pdev->dev, sizeof(*ep93xx_rtc), GFP_KERNEL);
if (!ep93xx_rtc)
return -ENOMEM;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
ep93xx_rtc->mmio_base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(ep93xx_rtc->mmio_base))
return PTR_ERR(ep93xx_rtc->mmio_base);
pdev->dev.platform_data = ep93xx_rtc;
platform_set_drvdata(pdev, ep93xx_rtc);
ep93xx_rtc->rtc = devm_rtc_device_register(&pdev->dev,
pdev->name, &ep93xx_rtc_ops, THIS_MODULE);
if (IS_ERR(ep93xx_rtc->rtc)) {
err = PTR_ERR(ep93xx_rtc->rtc);
goto exit;
}
err = sysfs_create_group(&pdev->dev.kobj, &ep93xx_rtc_sysfs_files);
if (err)
goto exit;
return 0;
exit:
pdev->dev.platform_data = NULL;
return err;
}
static int ep93xx_rtc_remove(struct platform_device *pdev)
{
sysfs_remove_group(&pdev->dev.kobj, &ep93xx_rtc_sysfs_files);
pdev->dev.platform_data = NULL;
return 0;
}
static struct platform_driver ep93xx_rtc_driver = {
.driver = {
.name = "ep93xx-rtc",
},
.probe = ep93xx_rtc_probe,
.remove = ep93xx_rtc_remove,
};
module_platform_driver(ep93xx_rtc_driver);
MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
MODULE_DESCRIPTION("EP93XX RTC driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:ep93xx-rtc");
