forked from Minki/linux
[PATCH] RTC: add rtc-ds1742 driver
Add an RTC driver for the Dallas DS1742 RTC chip. [akpm@osdl.org: cleanups, compile fix] Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Cc: Alessandro Zummo <a.zummo@towertech.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Atsushi Nemoto
Linus Torvalds
parent
9bf5b4f5f5
commit
5ec3e4b7ae
@ -131,6 +131,16 @@ config RTC_DRV_DS1672
|
||||
This driver can also be built as a module. If so, the module
|
||||
will be called rtc-ds1672.
|
||||
|
||||
config RTC_DRV_DS1742
|
||||
tristate "Dallas DS1742"
|
||||
depends on RTC_CLASS
|
||||
help
|
||||
If you say yes here you get support for the
|
||||
Dallas DS1742 timekeeping chip.
|
||||
|
||||
This driver can also be built as a module. If so, the module
|
||||
will be called rtc-ds1742.
|
||||
|
||||
config RTC_DRV_PCF8563
|
||||
tristate "Philips PCF8563/Epson RTC8564"
|
||||
depends on RTC_CLASS && I2C
|
||||
|
||||
@ -15,6 +15,7 @@ obj-$(CONFIG_RTC_DRV_X1205) += rtc-x1205.o
|
||||
obj-$(CONFIG_RTC_DRV_TEST) += rtc-test.o
|
||||
obj-$(CONFIG_RTC_DRV_DS1307) += rtc-ds1307.o
|
||||
obj-$(CONFIG_RTC_DRV_DS1672) += rtc-ds1672.o
|
||||
obj-$(CONFIG_RTC_DRV_DS1742) += rtc-ds1742.o
|
||||
obj-$(CONFIG_RTC_DRV_PCF8563) += rtc-pcf8563.o
|
||||
obj-$(CONFIG_RTC_DRV_PCF8583) += rtc-pcf8583.o
|
||||
obj-$(CONFIG_RTC_DRV_RS5C372) += rtc-rs5c372.o
|
||||
|
||||
259
drivers/rtc/rtc-ds1742.c
Normal file
259
drivers/rtc/rtc-ds1742.c
Normal file
@ -0,0 +1,259 @@
|
||||
/*
|
||||
* An rtc driver for the Dallas DS1742
|
||||
*
|
||||
* Copyright (C) 2006 Atsushi Nemoto <anemo@mba.ocn.ne.jp>
|
||||
*
|
||||
* 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/bcd.h>
|
||||
#include <linux/init.h>
|
||||
#include <linux/kernel.h>
|
||||
#include <linux/delay.h>
|
||||
#include <linux/jiffies.h>
|
||||
#include <linux/rtc.h>
|
||||
#include <linux/platform_device.h>
|
||||
#include <linux/io.h>
|
||||
|
||||
#define DRV_VERSION "0.1"
|
||||
|
||||
#define RTC_REG_SIZE 0x800
|
||||
#define RTC_OFFSET 0x7f8
|
||||
|
||||
#define RTC_CONTROL (RTC_OFFSET + 0)
|
||||
#define RTC_CENTURY (RTC_OFFSET + 0)
|
||||
#define RTC_SECONDS (RTC_OFFSET + 1)
|
||||
#define RTC_MINUTES (RTC_OFFSET + 2)
|
||||
#define RTC_HOURS (RTC_OFFSET + 3)
|
||||
#define RTC_DAY (RTC_OFFSET + 4)
|
||||
#define RTC_DATE (RTC_OFFSET + 5)
|
||||
#define RTC_MONTH (RTC_OFFSET + 6)
|
||||
#define RTC_YEAR (RTC_OFFSET + 7)
|
||||
|
||||
#define RTC_CENTURY_MASK 0x3f
|
||||
#define RTC_SECONDS_MASK 0x7f
|
||||
#define RTC_DAY_MASK 0x07
|
||||
|
||||
/* Bits in the Control/Century register */
|
||||
#define RTC_WRITE 0x80
|
||||
#define RTC_READ 0x40
|
||||
|
||||
/* Bits in the Seconds register */
|
||||
#define RTC_STOP 0x80
|
||||
|
||||
/* Bits in the Day register */
|
||||
#define RTC_BATT_FLAG 0x80
|
||||
|
||||
struct rtc_plat_data {
|
||||
struct rtc_device *rtc;
|
||||
void __iomem *ioaddr;
|
||||
unsigned long baseaddr;
|
||||
unsigned long last_jiffies;
|
||||
};
|
||||
|
||||
static int ds1742_rtc_set_time(struct device *dev, struct rtc_time *tm)
|
||||
{
|
||||
struct platform_device *pdev = to_platform_device(dev);
|
||||
struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
|
||||
void __iomem *ioaddr = pdata->ioaddr;
|
||||
u8 century;
|
||||
|
||||
century = BIN2BCD((tm->tm_year + 1900) / 100);
|
||||
|
||||
writeb(RTC_WRITE, ioaddr + RTC_CONTROL);
|
||||
|
||||
writeb(BIN2BCD(tm->tm_year % 100), ioaddr + RTC_YEAR);
|
||||
writeb(BIN2BCD(tm->tm_mon + 1), ioaddr + RTC_MONTH);
|
||||
writeb(BIN2BCD(tm->tm_wday) & RTC_DAY_MASK, ioaddr + RTC_DAY);
|
||||
writeb(BIN2BCD(tm->tm_mday), ioaddr + RTC_DATE);
|
||||
writeb(BIN2BCD(tm->tm_hour), ioaddr + RTC_HOURS);
|
||||
writeb(BIN2BCD(tm->tm_min), ioaddr + RTC_MINUTES);
|
||||
writeb(BIN2BCD(tm->tm_sec) & RTC_SECONDS_MASK, ioaddr + RTC_SECONDS);
|
||||
|
||||
/* RTC_CENTURY and RTC_CONTROL share same register */
|
||||
writeb(RTC_WRITE | (century & RTC_CENTURY_MASK), ioaddr + RTC_CENTURY);
|
||||
writeb(century & RTC_CENTURY_MASK, ioaddr + RTC_CONTROL);
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int ds1742_rtc_read_time(struct device *dev, struct rtc_time *tm)
|
||||
{
|
||||
struct platform_device *pdev = to_platform_device(dev);
|
||||
struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
|
||||
void __iomem *ioaddr = pdata->ioaddr;
|
||||
unsigned int year, month, day, hour, minute, second, week;
|
||||
unsigned int century;
|
||||
|
||||
/* give enough time to update RTC in case of continuous read */
|
||||
if (pdata->last_jiffies == jiffies)
|
||||
msleep(1);
|
||||
pdata->last_jiffies = jiffies;
|
||||
writeb(RTC_READ, ioaddr + RTC_CONTROL);
|
||||
second = readb(ioaddr + RTC_SECONDS) & RTC_SECONDS_MASK;
|
||||
minute = readb(ioaddr + RTC_MINUTES);
|
||||
hour = readb(ioaddr + RTC_HOURS);
|
||||
day = readb(ioaddr + RTC_DATE);
|
||||
week = readb(ioaddr + RTC_DAY) & RTC_DAY_MASK;
|
||||
month = readb(ioaddr + RTC_MONTH);
|
||||
year = readb(ioaddr + RTC_YEAR);
|
||||
century = readb(ioaddr + RTC_CENTURY) & RTC_CENTURY_MASK;
|
||||
writeb(0, ioaddr + RTC_CONTROL);
|
||||
tm->tm_sec = BCD2BIN(second);
|
||||
tm->tm_min = BCD2BIN(minute);
|
||||
tm->tm_hour = BCD2BIN(hour);
|
||||
tm->tm_mday = BCD2BIN(day);
|
||||
tm->tm_wday = BCD2BIN(week);
|
||||
tm->tm_mon = BCD2BIN(month) - 1;
|
||||
/* year is 1900 + tm->tm_year */
|
||||
tm->tm_year = BCD2BIN(year) + BCD2BIN(century) * 100 - 1900;
|
||||
|
||||
if (rtc_valid_tm(tm) < 0) {
|
||||
dev_err(dev, "retrieved date/time is not valid.\n");
|
||||
rtc_time_to_tm(0, tm);
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
static struct rtc_class_ops ds1742_rtc_ops = {
|
||||
.read_time = ds1742_rtc_read_time,
|
||||
.set_time = ds1742_rtc_set_time,
|
||||
};
|
||||
|
||||
static ssize_t ds1742_nvram_read(struct kobject *kobj, char *buf,
|
||||
loff_t pos, size_t size)
|
||||
{
|
||||
struct platform_device *pdev =
|
||||
to_platform_device(container_of(kobj, struct device, kobj));
|
||||
struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
|
||||
void __iomem *ioaddr = pdata->ioaddr;
|
||||
ssize_t count;
|
||||
|
||||
for (count = 0; size > 0 && pos < RTC_OFFSET; count++, size--)
|
||||
*buf++ = readb(ioaddr + pos++);
|
||||
return count;
|
||||
}
|
||||
|
||||
static ssize_t ds1742_nvram_write(struct kobject *kobj, char *buf,
|
||||
loff_t pos, size_t size)
|
||||
{
|
||||
struct platform_device *pdev =
|
||||
to_platform_device(container_of(kobj, struct device, kobj));
|
||||
struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
|
||||
void __iomem *ioaddr = pdata->ioaddr;
|
||||
ssize_t count;
|
||||
|
||||
for (count = 0; size > 0 && pos < RTC_OFFSET; count++, size--)
|
||||
writeb(*buf++, ioaddr + pos++);
|
||||
return count;
|
||||
}
|
||||
|
||||
static struct bin_attribute ds1742_nvram_attr = {
|
||||
.attr = {
|
||||
.name = "nvram",
|
||||
.mode = S_IRUGO | S_IWUGO,
|
||||
.owner = THIS_MODULE,
|
||||
},
|
||||
.size = RTC_OFFSET,
|
||||
.read = ds1742_nvram_read,
|
||||
.write = ds1742_nvram_write,
|
||||
};
|
||||
|
||||
static int __init ds1742_rtc_probe(struct platform_device *pdev)
|
||||
{
|
||||
struct rtc_device *rtc;
|
||||
struct resource *res;
|
||||
unsigned int cen, sec;
|
||||
struct rtc_plat_data *pdata = NULL;
|
||||
void __iomem *ioaddr = NULL;
|
||||
int ret = 0;
|
||||
|
||||
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
||||
if (!res)
|
||||
return -ENODEV;
|
||||
pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
|
||||
if (!pdata)
|
||||
return -ENOMEM;
|
||||
if (!request_mem_region(res->start, RTC_REG_SIZE, pdev->name)) {
|
||||
ret = -EBUSY;
|
||||
goto out;
|
||||
}
|
||||
pdata->baseaddr = res->start;
|
||||
ioaddr = ioremap(pdata->baseaddr, RTC_REG_SIZE);
|
||||
if (!ioaddr) {
|
||||
ret = -ENOMEM;
|
||||
goto out;
|
||||
}
|
||||
pdata->ioaddr = ioaddr;
|
||||
|
||||
/* turn RTC on if it was not on */
|
||||
sec = readb(ioaddr + RTC_SECONDS);
|
||||
if (sec & RTC_STOP) {
|
||||
sec &= RTC_SECONDS_MASK;
|
||||
cen = readb(ioaddr + RTC_CENTURY) & RTC_CENTURY_MASK;
|
||||
writeb(RTC_WRITE, ioaddr + RTC_CONTROL);
|
||||
writeb(sec, ioaddr + RTC_SECONDS);
|
||||
writeb(cen & RTC_CENTURY_MASK, ioaddr + RTC_CONTROL);
|
||||
}
|
||||
if (readb(ioaddr + RTC_DAY) & RTC_BATT_FLAG)
|
||||
dev_warn(&pdev->dev, "voltage-low detected.\n");
|
||||
|
||||
rtc = rtc_device_register(pdev->name, &pdev->dev,
|
||||
&ds1742_rtc_ops, THIS_MODULE);
|
||||
if (IS_ERR(rtc)) {
|
||||
ret = PTR_ERR(rtc);
|
||||
goto out;
|
||||
}
|
||||
pdata->rtc = rtc;
|
||||
pdata->last_jiffies = jiffies;
|
||||
platform_set_drvdata(pdev, pdata);
|
||||
sysfs_create_bin_file(&pdev->dev.kobj, &ds1742_nvram_attr);
|
||||
return 0;
|
||||
out:
|
||||
if (ioaddr)
|
||||
iounmap(ioaddr);
|
||||
if (pdata->baseaddr)
|
||||
release_mem_region(pdata->baseaddr, RTC_REG_SIZE);
|
||||
kfree(pdata);
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int __devexit ds1742_rtc_remove(struct platform_device *pdev)
|
||||
{
|
||||
struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
|
||||
|
||||
sysfs_remove_bin_file(&pdev->dev.kobj, &ds1742_nvram_attr);
|
||||
rtc_device_unregister(pdata->rtc);
|
||||
iounmap(pdata->ioaddr);
|
||||
release_mem_region(pdata->baseaddr, RTC_REG_SIZE);
|
||||
kfree(pdata);
|
||||
return 0;
|
||||
}
|
||||
|
||||
static struct platform_driver ds1742_rtc_driver = {
|
||||
.probe = ds1742_rtc_probe,
|
||||
.remove = __devexit_p(ds1742_rtc_remove),
|
||||
.driver = {
|
||||
.name = "ds1742",
|
||||
.owner = THIS_MODULE,
|
||||
},
|
||||
};
|
||||
|
||||
static __init int ds1742_init(void)
|
||||
{
|
||||
return platform_driver_register(&ds1742_rtc_driver);
|
||||
}
|
||||
|
||||
static __exit void ds1742_exit(void)
|
||||
{
|
||||
return platform_driver_unregister(&ds1742_rtc_driver);
|
||||
}
|
||||
|
||||
module_init(ds1742_init);
|
||||
module_exit(ds1742_exit);
|
||||
|
||||
MODULE_AUTHOR("Atsushi Nemoto <anemo@mba.ocn.ne.jp>");
|
||||
MODULE_DESCRIPTION("Dallas DS1742 RTC driver");
|
||||
MODULE_LICENSE("GPL");
|
||||
MODULE_VERSION(DRV_VERSION);
|
||||
Loading…
Reference in New Issue
Block a user