- 根目录:
- drivers
- rtc
- rtc-ds1343.c
/* rtc-ds1343.c
*
* Driver for Dallas Semiconductor DS1343 Low Current, SPI Compatible
* Real Time Clock
*
* Author : Raghavendra Chandra Ganiga <ravi23ganiga@gmail.com>
* Ankur Srivastava <sankurece@gmail.com> : DS1343 Nvram Support
*
* 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/init.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/device.h>
#include <linux/spi/spi.h>
#include <linux/regmap.h>
#include <linux/rtc.h>
#include <linux/bcd.h>
#include <linux/pm.h>
#include <linux/pm_wakeirq.h>
#include <linux/slab.h>
#define DS1343_DRV_VERSION "01.00"
#define DALLAS_MAXIM_DS1343 0
#define DALLAS_MAXIM_DS1344 1
/* RTC DS1343 Registers */
#define DS1343_SECONDS_REG 0x00
#define DS1343_MINUTES_REG 0x01
#define DS1343_HOURS_REG 0x02
#define DS1343_DAY_REG 0x03
#define DS1343_DATE_REG 0x04
#define DS1343_MONTH_REG 0x05
#define DS1343_YEAR_REG 0x06
#define DS1343_ALM0_SEC_REG 0x07
#define DS1343_ALM0_MIN_REG 0x08
#define DS1343_ALM0_HOUR_REG 0x09
#define DS1343_ALM0_DAY_REG 0x0A
#define DS1343_ALM1_SEC_REG 0x0B
#define DS1343_ALM1_MIN_REG 0x0C
#define DS1343_ALM1_HOUR_REG 0x0D
#define DS1343_ALM1_DAY_REG 0x0E
#define DS1343_CONTROL_REG 0x0F
#define DS1343_STATUS_REG 0x10
#define DS1343_TRICKLE_REG 0x11
#define DS1343_NVRAM 0x20
#define DS1343_NVRAM_LEN 96
/* DS1343 Control Registers bits */
#define DS1343_EOSC 0x80
#define DS1343_DOSF 0x20
#define DS1343_EGFIL 0x10
#define DS1343_SQW 0x08
#define DS1343_INTCN 0x04
#define DS1343_A1IE 0x02
#define DS1343_A0IE 0x01
/* DS1343 Status Registers bits */
#define DS1343_OSF 0x80
#define DS1343_IRQF1 0x02
#define DS1343_IRQF0 0x01
/* DS1343 Trickle Charger Registers bits */
#define DS1343_TRICKLE_MAGIC 0xa0
#define DS1343_TRICKLE_DS1 0x08
#define DS1343_TRICKLE_1K 0x01
#define DS1343_TRICKLE_2K 0x02
#define DS1343_TRICKLE_4K 0x03
static const struct spi_device_id ds1343_id[] = {
{ "ds1343", DALLAS_MAXIM_DS1343 },
{ "ds1344", DALLAS_MAXIM_DS1344 },
{ }
};
MODULE_DEVICE_TABLE(spi, ds1343_id);
struct ds1343_priv {
struct spi_device *spi;
struct rtc_device *rtc;
struct regmap *map;
struct mutex mutex;
unsigned int irqen;
int irq;
int alarm_sec;
int alarm_min;
int alarm_hour;
int alarm_mday;
};
static int ds1343_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
{
switch (cmd) {
#ifdef RTC_SET_CHARGE
case RTC_SET_CHARGE:
{
int val;
if (copy_from_user(&val, (int __user *)arg, sizeof(int)))
return -EFAULT;
return regmap_write(priv->map, DS1343_TRICKLE_REG, val);
}
break;
#endif
}
return -ENOIOCTLCMD;
}
static ssize_t ds1343_show_glitchfilter(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct ds1343_priv *priv = dev_get_drvdata(dev);
int glitch_filt_status, data;
regmap_read(priv->map, DS1343_CONTROL_REG, &data);
glitch_filt_status = !!(data & DS1343_EGFIL);
if (glitch_filt_status)
return sprintf(buf, "enabled\n");
else
return sprintf(buf, "disabled\n");
}
static ssize_t ds1343_store_glitchfilter(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct ds1343_priv *priv = dev_get_drvdata(dev);
int data;
regmap_read(priv->map, DS1343_CONTROL_REG, &data);
if (strncmp(buf, "enabled", 7) == 0)
data |= DS1343_EGFIL;
else if (strncmp(buf, "disabled", 8) == 0)
data &= ~(DS1343_EGFIL);
else
return -EINVAL;
regmap_write(priv->map, DS1343_CONTROL_REG, data);
return count;
}
static DEVICE_ATTR(glitch_filter, S_IRUGO | S_IWUSR, ds1343_show_glitchfilter,
ds1343_store_glitchfilter);
static ssize_t ds1343_nvram_write(struct file *filp, struct kobject *kobj,
struct bin_attribute *attr,
char *buf, loff_t off, size_t count)
{
int ret;
unsigned char address;
struct device *dev = kobj_to_dev(kobj);
struct ds1343_priv *priv = dev_get_drvdata(dev);
address = DS1343_NVRAM + off;
ret = regmap_bulk_write(priv->map, address, buf, count);
if (ret < 0)
dev_err(&priv->spi->dev, "Error in nvram write %d", ret);
return (ret < 0) ? ret : count;
}
static ssize_t ds1343_nvram_read(struct file *filp, struct kobject *kobj,
struct bin_attribute *attr,
char *buf, loff_t off, size_t count)
{
int ret;
unsigned char address;
struct device *dev = kobj_to_dev(kobj);
struct ds1343_priv *priv = dev_get_drvdata(dev);
address = DS1343_NVRAM + off;
ret = regmap_bulk_read(priv->map, address, buf, count);
if (ret < 0)
dev_err(&priv->spi->dev, "Error in nvram read %d\n", ret);
return (ret < 0) ? ret : count;
}
static struct bin_attribute nvram_attr = {
.attr.name = "nvram",
.attr.mode = S_IRUGO | S_IWUSR,
.read = ds1343_nvram_read,
.write = ds1343_nvram_write,
.size = DS1343_NVRAM_LEN,
};
static ssize_t ds1343_show_alarmstatus(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct ds1343_priv *priv = dev_get_drvdata(dev);
int alarmstatus, data;
regmap_read(priv->map, DS1343_CONTROL_REG, &data);
alarmstatus = !!(data & DS1343_A0IE);
if (alarmstatus)
return sprintf(buf, "enabled\n");
else
return sprintf(buf, "disabled\n");
}
static DEVICE_ATTR(alarm_status, S_IRUGO, ds1343_show_alarmstatus, NULL);
static ssize_t ds1343_show_alarmmode(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct ds1343_priv *priv = dev_get_drvdata(dev);
int alarm_mode, data;
char *alarm_str;
regmap_read(priv->map, DS1343_ALM0_SEC_REG, &data);
alarm_mode = (data & 0x80) >> 4;
regmap_read(priv->map, DS1343_ALM0_MIN_REG, &data);
alarm_mode |= (data & 0x80) >> 5;
regmap_read(priv->map, DS1343_ALM0_HOUR_REG, &data);
alarm_mode |= (data & 0x80) >> 6;
regmap_read(priv->map, DS1343_ALM0_DAY_REG, &data);
alarm_mode |= (data & 0x80) >> 7;
switch (alarm_mode) {
case 15:
alarm_str = "each second";
break;
case 7:
alarm_str = "seconds match";
break;
case 3:
alarm_str = "minutes and seconds match";
break;
case 1:
alarm_str = "hours, minutes and seconds match";
break;
case 0:
alarm_str = "day, hours, minutes and seconds match";
break;
default:
alarm_str = "invalid";
break;
}
return sprintf(buf, "%s\n", alarm_str);
}
static DEVICE_ATTR(alarm_mode, S_IRUGO, ds1343_show_alarmmode, NULL);
static ssize_t ds1343_show_tricklecharger(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct ds1343_priv *priv = dev_get_drvdata(dev);
int data;
char *diodes = "disabled", *resistors = " ";
regmap_read(priv->map, DS1343_TRICKLE_REG, &data);
if ((data & 0xf0) == DS1343_TRICKLE_MAGIC) {
switch (data & 0x0c) {
case DS1343_TRICKLE_DS1:
diodes = "one diode,";
break;
default:
diodes = "no diode,";
break;
}
switch (data & 0x03) {
case DS1343_TRICKLE_1K:
resistors = "1k Ohm";
break;
case DS1343_TRICKLE_2K:
resistors = "2k Ohm";
break;
case DS1343_TRICKLE_4K:
resistors = "4k Ohm";
break;
default:
diodes = "disabled";
break;
}
}
return sprintf(buf, "%s %s\n", diodes, resistors);
}
static DEVICE_ATTR(trickle_charger, S_IRUGO, ds1343_show_tricklecharger, NULL);
static int ds1343_sysfs_register(struct device *dev)
{
struct ds1343_priv *priv = dev_get_drvdata(dev);
int err;
err = device_create_file(dev, &dev_attr_glitch_filter);
if (err)
return err;
err = device_create_file(dev, &dev_attr_trickle_charger);
if (err)
goto error1;
err = device_create_bin_file(dev, &nvram_attr);
if (err)
goto error2;
if (priv->irq <= 0)
return err;
err = device_create_file(dev, &dev_attr_alarm_mode);
if (err)
goto error3;
err = device_create_file(dev, &dev_attr_alarm_status);
if (!err)
return err;
device_remove_file(dev, &dev_attr_alarm_mode);
error3:
device_remove_bin_file(dev, &nvram_attr);
error2:
device_remove_file(dev, &dev_attr_trickle_charger);
error1:
device_remove_file(dev, &dev_attr_glitch_filter);
return err;
}
static void ds1343_sysfs_unregister(struct device *dev)
{
struct ds1343_priv *priv = dev_get_drvdata(dev);
device_remove_file(dev, &dev_attr_glitch_filter);
device_remove_file(dev, &dev_attr_trickle_charger);
device_remove_bin_file(dev, &nvram_attr);
if (priv->irq <= 0)
return;
device_remove_file(dev, &dev_attr_alarm_status);
device_remove_file(dev, &dev_attr_alarm_mode);
}
static int ds1343_read_time(struct device *dev, struct rtc_time *dt)
{
struct ds1343_priv *priv = dev_get_drvdata(dev);
unsigned char buf[7];
int res;
res = regmap_bulk_read(priv->map, DS1343_SECONDS_REG, buf, 7);
if (res)
return res;
dt->tm_sec = bcd2bin(buf[0]);
dt->tm_min = bcd2bin(buf[1]);
dt->tm_hour = bcd2bin(buf[2] & 0x3F);
dt->tm_wday = bcd2bin(buf[3]) - 1;
dt->tm_mday = bcd2bin(buf[4]);
dt->tm_mon = bcd2bin(buf[5] & 0x1F) - 1;
dt->tm_year = bcd2bin(buf[6]) + 100; /* year offset from 1900 */
return rtc_valid_tm(dt);
}
static int ds1343_set_time(struct device *dev, struct rtc_time *dt)
{
struct ds1343_priv *priv = dev_get_drvdata(dev);
int res;
res = regmap_write(priv->map, DS1343_SECONDS_REG,
bin2bcd(dt->tm_sec));
if (res)
return res;
res = regmap_write(priv->map, DS1343_MINUTES_REG,
bin2bcd(dt->tm_min));
if (res)
return res;
res = regmap_write(priv->map, DS1343_HOURS_REG,
bin2bcd(dt->tm_hour) & 0x3F);
if (res)
return res;
res = regmap_write(priv->map, DS1343_DAY_REG,
bin2bcd(dt->tm_wday + 1));
if (res)
return res;
res = regmap_write(priv->map, DS1343_DATE_REG,
bin2bcd(dt->tm_mday));
if (res)
return res;
res = regmap_write(priv->map, DS1343_MONTH_REG,
bin2bcd(dt->tm_mon + 1));
if (res)
return res;
dt->tm_year %= 100;
res = regmap_write(priv->map, DS1343_YEAR_REG,
bin2bcd(dt->tm_year));
if (res)
return res;
return 0;
}
static int ds1343_update_alarm(struct device *dev)
{
struct ds1343_priv *priv = dev_get_drvdata(dev);
unsigned int control, stat;
unsigned char buf[4];
int res = 0;
res = regmap_read(priv->map, DS1343_CONTROL_REG, &control);
if (res)
return res;
res = regmap_read(priv->map, DS1343_STATUS_REG, &stat);
if (res)
return res;
control &= ~(DS1343_A0IE);
stat &= ~(DS1343_IRQF0);
res = regmap_write(priv->map, DS1343_CONTROL_REG, control);
if (res)
return res;
res = regmap_write(priv->map, DS1343_STATUS_REG, stat);
if (res)
return res;
buf[0] = priv->alarm_sec < 0 || (priv->irqen & RTC_UF) ?
0x80 : bin2bcd(priv->alarm_sec) & 0x7F;
buf[1] = priv->alarm_min < 0 || (priv->irqen & RTC_UF) ?
0x80 : bin2bcd(priv->alarm_min) & 0x7F;
buf[2] = priv->alarm_hour < 0 || (priv->irqen & RTC_UF) ?
0x80 : bin2bcd(priv->alarm_hour) & 0x3F;
buf[3] = priv->alarm_mday < 0 || (priv->irqen & RTC_UF) ?
0x80 : bin2bcd(priv->alarm_mday) & 0x7F;
res = regmap_bulk_write(priv->map, DS1343_ALM0_SEC_REG, buf, 4);
if (res)
return res;
if (priv->irqen) {
control |= DS1343_A0IE;
res = regmap_write(priv->map, DS1343_CONTROL_REG, control);
}
return res;
}
static int ds1343_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
{
struct ds1343_priv *priv = dev_get_drvdata(dev);
int res = 0;
unsigned int stat;
if (priv->irq <= 0)
return -EINVAL;
mutex_lock(&priv->mutex);
res = regmap_read(priv->map, DS1343_STATUS_REG, &stat);
if (res)
goto out;
alarm->enabled = !!(priv->irqen & RTC_AF);
alarm->pending = !!(stat & DS1343_IRQF0);
alarm->time.tm_sec = priv->alarm_sec < 0 ? 0 : priv->alarm_sec;
alarm->time.tm_min = priv->alarm_min < 0 ? 0 : priv->alarm_min;
alarm->time.tm_hour = priv->alarm_hour < 0 ? 0 : priv->alarm_hour;
alarm->time.tm_mday = priv->alarm_mday < 0 ? 0 : priv->alarm_mday;
alarm->time.tm_mon = -1;
alarm->time.tm_year = -1;
alarm->time.tm_wday = -1;
alarm->time.tm_yday = -1;
alarm->time.tm_isdst = -1;
out:
mutex_unlock(&priv->mutex);
return res;
}
static int ds1343_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
{
struct ds1343_priv *priv = dev_get_drvdata(dev);
int res = 0;
if (priv->irq <= 0)
return -EINVAL;
mutex_lock(&priv->mutex);
priv->alarm_sec = alarm->time.tm_sec;
priv->alarm_min = alarm->time.tm_min;
priv->alarm_hour = alarm->time.tm_hour;
priv->alarm_mday = alarm->time.tm_mday;
if (alarm->enabled)
priv->irqen |= RTC_AF;
res = ds1343_update_alarm(dev);
mutex_unlock(&priv->mutex);
return res;
}
static int ds1343_alarm_irq_enable(struct device *dev, unsigned int enabled)
{
struct ds1343_priv *priv = dev_get_drvdata(dev);
int res = 0;
if (priv->irq <= 0)
return -EINVAL;
mutex_lock(&priv->mutex);
if (enabled)
priv->irqen |= RTC_AF;
else
priv->irqen &= ~RTC_AF;
res = ds1343_update_alarm(dev);
mutex_unlock(&priv->mutex);
return res;
}
static irqreturn_t ds1343_thread(int irq, void *dev_id)
{
struct ds1343_priv *priv = dev_id;
unsigned int stat, control;
int res = 0;
mutex_lock(&priv->mutex);
res = regmap_read(priv->map, DS1343_STATUS_REG, &stat);
if (res)
goto out;
if (stat & DS1343_IRQF0) {
stat &= ~DS1343_IRQF0;
regmap_write(priv->map, DS1343_STATUS_REG, stat);
res = regmap_read(priv->map, DS1343_CONTROL_REG, &control);
if (res)
goto out;
control &= ~DS1343_A0IE;
regmap_write(priv->map, DS1343_CONTROL_REG, control);
rtc_update_irq(priv->rtc, 1, RTC_AF | RTC_IRQF);
}
out:
mutex_unlock(&priv->mutex);
return IRQ_HANDLED;
}
static const struct rtc_class_ops ds1343_rtc_ops = {
.ioctl = ds1343_ioctl,
.read_time = ds1343_read_time,
.set_time = ds1343_set_time,
.read_alarm = ds1343_read_alarm,
.set_alarm = ds1343_set_alarm,
.alarm_irq_enable = ds1343_alarm_irq_enable,
};
static int ds1343_probe(struct spi_device *spi)
{
struct ds1343_priv *priv;
struct regmap_config config;
unsigned int data;
int res;
memset(&config, 0, sizeof(config));
config.reg_bits = 8;
config.val_bits = 8;
config.write_flag_mask = 0x80;
priv = devm_kzalloc(&spi->dev, sizeof(struct ds1343_priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
priv->spi = spi;
mutex_init(&priv->mutex);
/* RTC DS1347 works in spi mode 3 and
* its chip select is active high
*/
spi->mode = SPI_MODE_3 | SPI_CS_HIGH;
spi->bits_per_word = 8;
res = spi_setup(spi);
if (res)
return res;
spi_set_drvdata(spi, priv);
priv->map = devm_regmap_init_spi(spi, &config);
if (IS_ERR(priv->map)) {
dev_err(&spi->dev, "spi regmap init failed for rtc ds1343\n");
return PTR_ERR(priv->map);
}
res = regmap_read(priv->map, DS1343_SECONDS_REG, &data);
if (res)
return res;
regmap_read(priv->map, DS1343_CONTROL_REG, &data);
data |= DS1343_INTCN;
data &= ~(DS1343_EOSC | DS1343_A1IE | DS1343_A0IE);
regmap_write(priv->map, DS1343_CONTROL_REG, data);
regmap_read(priv->map, DS1343_STATUS_REG, &data);
data &= ~(DS1343_OSF | DS1343_IRQF1 | DS1343_IRQF0);
regmap_write(priv->map, DS1343_STATUS_REG, data);
priv->rtc = devm_rtc_device_register(&spi->dev, "ds1343",
&ds1343_rtc_ops, THIS_MODULE);
if (IS_ERR(priv->rtc)) {
dev_err(&spi->dev, "unable to register rtc ds1343\n");
return PTR_ERR(priv->rtc);
}
priv->irq = spi->irq;
if (priv->irq >= 0) {
res = devm_request_threaded_irq(&spi->dev, spi->irq, NULL,
ds1343_thread, IRQF_ONESHOT,
"ds1343", priv);
if (res) {
priv->irq = -1;
dev_err(&spi->dev,
"unable to request irq for rtc ds1343\n");
} else {
device_init_wakeup(&spi->dev, true);
dev_pm_set_wake_irq(&spi->dev, spi->irq);
}
}
res = ds1343_sysfs_register(&spi->dev);
if (res)
dev_err(&spi->dev,
"unable to create sysfs entries for rtc ds1343\n");
return 0;
}
static int ds1343_remove(struct spi_device *spi)
{
struct ds1343_priv *priv = spi_get_drvdata(spi);
if (spi->irq) {
mutex_lock(&priv->mutex);
priv->irqen &= ~RTC_AF;
mutex_unlock(&priv->mutex);
dev_pm_clear_wake_irq(&spi->dev);
device_init_wakeup(&spi->dev, false);
devm_free_irq(&spi->dev, spi->irq, priv);
}
spi_set_drvdata(spi, NULL);
ds1343_sysfs_unregister(&spi->dev);
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int ds1343_suspend(struct device *dev)
{
struct spi_device *spi = to_spi_device(dev);
if (spi->irq >= 0 && device_may_wakeup(dev))
enable_irq_wake(spi->irq);
return 0;
}
static int ds1343_resume(struct device *dev)
{
struct spi_device *spi = to_spi_device(dev);
if (spi->irq >= 0 && device_may_wakeup(dev))
disable_irq_wake(spi->irq);
return 0;
}
#endif
static SIMPLE_DEV_PM_OPS(ds1343_pm, ds1343_suspend, ds1343_resume);
static struct spi_driver ds1343_driver = {
.driver = {
.name = "ds1343",
.pm = &ds1343_pm,
},
.probe = ds1343_probe,
.remove = ds1343_remove,
.id_table = ds1343_id,
};
module_spi_driver(ds1343_driver);
MODULE_DESCRIPTION("DS1343 RTC SPI Driver");
MODULE_AUTHOR("Raghavendra Chandra Ganiga <ravi23ganiga@gmail.com>,"
"Ankur Srivastava <sankurece@gmail.com>");
MODULE_LICENSE("GPL v2");
MODULE_VERSION(DS1343_DRV_VERSION);