/*
* 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>
#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
#define DRV_VERSION "0.3"
/*
* 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;
};
static int ep93xx_rtc_get_swcomp(struct device *dev, unsigned short *preload,
unsigned short *delete)
{
struct ep93xx_rtc *ep93xx_rtc = dev->platform_data;
unsigned long comp;
comp = __raw_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->platform_data;
unsigned long time;
time = __raw_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->platform_data;
__raw_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 int __init ep93xx_rtc_probe(struct platform_device *pdev)
{
struct ep93xx_rtc *ep93xx_rtc;
struct resource *res;
struct rtc_device *rtc;
int err;
ep93xx_rtc = kzalloc(sizeof(struct ep93xx_rtc), GFP_KERNEL);
if (ep93xx_rtc == NULL)
return -ENOMEM;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (res == NULL) {
err = -ENXIO;
goto fail_free;
}
res = request_mem_region(res->start, resource_size(res), pdev->name);
if (res == NULL) {
err = -EBUSY;
goto fail_free;
}
ep93xx_rtc->mmio_base = ioremap(res->start, resource_size(res));
if (ep93xx_rtc->mmio_base == NULL) {
err = -ENXIO;
goto fail;
}
pdev->dev.platform_data = ep93xx_rtc;
rtc = rtc_device_register(pdev->name,
&pdev->dev, &ep93xx_rtc_ops, THIS_MODULE);
if (IS_ERR(rtc)) {
err = PTR_ERR(rtc);
goto fail;
}
platform_set_drvdata(pdev, rtc);
err = device_create_file(&pdev->dev, &dev_attr_comp_preload);
if (err)
goto fail;
err = device_create_file(&pdev->dev, &dev_attr_comp_delete);
if (err) {
device_remove_file(&pdev->dev, &dev_attr_comp_preload);
goto fail;
}
return 0;
fail:
if (ep93xx_rtc->mmio_base) {
iounmap(ep93xx_rtc->mmio_base);
pdev->dev.platform_data = NULL;
}
release_mem_region(res->start, resource_size(res));
fail_free:
kfree(ep93xx_rtc);
return err;
}
static int __exit ep93xx_rtc_remove(struct platform_device *pdev)
{
struct rtc_device *rtc = platform_get_drvdata(pdev);
struct ep93xx_rtc *ep93xx_rtc = pdev->dev.platform_data;
struct resource *res;
/* cleanup sysfs */
device_remove_file(&pdev->dev, &dev_attr_comp_delete);
device_remove_file(&pdev->dev, &dev_attr_comp_preload);
rtc_device_unregister(rtc);
iounmap(ep93xx_rtc->mmio_base);
pdev->dev.platform_data = NULL;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
release_mem_region(res->start, resource_size(res));
platform_set_drvdata(pdev, NULL);
return 0;
}
/* work with hotplug and coldplug */
MODULE_ALIAS("platform:ep93xx-rtc");
static struct platform_driver ep93xx_rtc_driver = {
.driver = {
.name = "ep93xx-rtc",
.owner = THIS_MODULE,
},
.remove = __exit_p(ep93xx_rtc_remove),
};
static int __init ep93xx_rtc_init(void)
{
return platform_driver_probe(&ep93xx_rtc_driver, ep93xx_rtc_probe);
}
static void __exit ep93xx_rtc_exit(void)
{
platform_driver_unregister(&ep93xx_rtc_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);
