rtc: add Intersil ISL12022 RTC driver
- derived from rtc-pcf8563 - no SRAM driver Signed-off-by: Roman Fietze <roman.fietze@telemotive.de> Cc: Wan ZongShun <mcuos.com@gmail.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Roman Fietze
Linus Torvalds
parent
eba545465f
commit
d6c7428f9c
|
|
@ -203,6 +203,15 @@ config RTC_DRV_ISL1208
|
|||
This driver can also be built as a module. If so, the module
|
||||
will be called rtc-isl1208.
|
||||
|
||||
config RTC_DRV_ISL12022
|
||||
tristate "Intersil ISL12022"
|
||||
help
|
||||
If you say yes here you get support for the
|
||||
Intersil ISL12022 RTC chip.
|
||||
|
||||
This driver can also be built as a module. If so, the module
|
||||
will be called rtc-isl12022.
|
||||
|
||||
config RTC_DRV_X1205
|
||||
tristate "Xicor/Intersil X1205"
|
||||
help
|
||||
|
|
|
|||
|
|
@ -48,6 +48,7 @@ obj-$(CONFIG_RTC_DRV_FM3130) += rtc-fm3130.o
|
|||
obj-$(CONFIG_RTC_DRV_GENERIC) += rtc-generic.o
|
||||
obj-$(CONFIG_RTC_DRV_IMXDI) += rtc-imxdi.o
|
||||
obj-$(CONFIG_RTC_DRV_ISL1208) += rtc-isl1208.o
|
||||
obj-$(CONFIG_RTC_DRV_ISL12022) += rtc-isl12022.o
|
||||
obj-$(CONFIG_RTC_DRV_JZ4740) += rtc-jz4740.o
|
||||
obj-$(CONFIG_RTC_DRV_M41T80) += rtc-m41t80.o
|
||||
obj-$(CONFIG_RTC_DRV_M41T94) += rtc-m41t94.o
|
||||
|
|
|
|||
|
|
@ -0,0 +1,327 @@
|
|||
/*
|
||||
* An I2C driver for the Intersil ISL 12022
|
||||
*
|
||||
* Author: Roman Fietze <roman.fietze@telemotive.de>
|
||||
*
|
||||
* Based on the Philips PCF8563 RTC
|
||||
* by 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/i2c.h>
|
||||
#include <linux/bcd.h>
|
||||
#include <linux/rtc.h>
|
||||
#include <linux/slab.h>
|
||||
|
||||
#define DRV_VERSION "0.1"
|
||||
|
||||
/* ISL register offsets */
|
||||
#define ISL12022_REG_SC 0x00
|
||||
#define ISL12022_REG_MN 0x01
|
||||
#define ISL12022_REG_HR 0x02
|
||||
#define ISL12022_REG_DT 0x03
|
||||
#define ISL12022_REG_MO 0x04
|
||||
#define ISL12022_REG_YR 0x05
|
||||
#define ISL12022_REG_DW 0x06
|
||||
|
||||
#define ISL12022_REG_SR 0x07
|
||||
#define ISL12022_REG_INT 0x08
|
||||
|
||||
/* ISL register bits */
|
||||
#define ISL12022_HR_MIL (1 << 7) /* military or 24 hour time */
|
||||
|
||||
#define ISL12022_SR_LBAT85 (1 << 2)
|
||||
#define ISL12022_SR_LBAT75 (1 << 1)
|
||||
|
||||
#define ISL12022_INT_WRTC (1 << 6)
|
||||
|
||||
|
||||
static struct i2c_driver isl12022_driver;
|
||||
|
||||
struct isl12022 {
|
||||
struct rtc_device *rtc;
|
||||
|
||||
bool write_enabled; /* true if write enable is set */
|
||||
};
|
||||
|
||||
|
||||
static int isl12022_read_regs(struct i2c_client *client, uint8_t reg,
|
||||
uint8_t *data, size_t n)
|
||||
{
|
||||
struct i2c_msg msgs[] = {
|
||||
{
|
||||
.addr = client->addr,
|
||||
.flags = 0,
|
||||
.len = 1,
|
||||
.buf = data
|
||||
}, /* setup read ptr */
|
||||
{
|
||||
.addr = client->addr,
|
||||
.flags = I2C_M_RD,
|
||||
.len = n,
|
||||
.buf = data
|
||||
}
|
||||
};
|
||||
|
||||
int ret;
|
||||
|
||||
data[0] = reg;
|
||||
ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
|
||||
if (ret != ARRAY_SIZE(msgs)) {
|
||||
dev_err(&client->dev, "%s: read error, ret=%d\n",
|
||||
__func__, ret);
|
||||
return -EIO;
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
|
||||
static int isl12022_write_reg(struct i2c_client *client,
|
||||
uint8_t reg, uint8_t val)
|
||||
{
|
||||
uint8_t data[2] = { reg, val };
|
||||
int err;
|
||||
|
||||
err = i2c_master_send(client, data, sizeof(data));
|
||||
if (err != sizeof(data)) {
|
||||
dev_err(&client->dev,
|
||||
"%s: err=%d addr=%02x, data=%02x\n",
|
||||
__func__, err, data[0], data[1]);
|
||||
return -EIO;
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
|
||||
/*
|
||||
* In the routines that deal directly with the isl12022 hardware, we use
|
||||
* rtc_time -- month 0-11, hour 0-23, yr = calendar year-epoch.
|
||||
*/
|
||||
static int isl12022_get_datetime(struct i2c_client *client, struct rtc_time *tm)
|
||||
{
|
||||
uint8_t buf[ISL12022_REG_INT + 1];
|
||||
int ret;
|
||||
|
||||
ret = isl12022_read_regs(client, ISL12022_REG_SC, buf, sizeof(buf));
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
if (buf[ISL12022_REG_SR] & (ISL12022_SR_LBAT85 | ISL12022_SR_LBAT75)) {
|
||||
dev_warn(&client->dev,
|
||||
"voltage dropped below %u%%, "
|
||||
"date and time is not reliable.\n",
|
||||
buf[ISL12022_REG_SR] & ISL12022_SR_LBAT85 ? 85 : 75);
|
||||
}
|
||||
|
||||
dev_dbg(&client->dev,
|
||||
"%s: raw data is sec=%02x, min=%02x, hr=%02x, "
|
||||
"mday=%02x, mon=%02x, year=%02x, wday=%02x, "
|
||||
"sr=%02x, int=%02x",
|
||||
__func__,
|
||||
buf[ISL12022_REG_SC],
|
||||
buf[ISL12022_REG_MN],
|
||||
buf[ISL12022_REG_HR],
|
||||
buf[ISL12022_REG_DT],
|
||||
buf[ISL12022_REG_MO],
|
||||
buf[ISL12022_REG_YR],
|
||||
buf[ISL12022_REG_DW],
|
||||
buf[ISL12022_REG_SR],
|
||||
buf[ISL12022_REG_INT]);
|
||||
|
||||
tm->tm_sec = bcd2bin(buf[ISL12022_REG_SC] & 0x7F);
|
||||
tm->tm_min = bcd2bin(buf[ISL12022_REG_MN] & 0x7F);
|
||||
tm->tm_hour = bcd2bin(buf[ISL12022_REG_HR] & 0x3F);
|
||||
tm->tm_mday = bcd2bin(buf[ISL12022_REG_DT] & 0x3F);
|
||||
tm->tm_wday = buf[ISL12022_REG_DW] & 0x07;
|
||||
tm->tm_mon = bcd2bin(buf[ISL12022_REG_MO] & 0x1F) - 1;
|
||||
tm->tm_year = bcd2bin(buf[ISL12022_REG_YR]) + 100;
|
||||
|
||||
dev_dbg(&client->dev, "%s: secs=%d, mins=%d, hours=%d, "
|
||||
"mday=%d, mon=%d, year=%d, wday=%d\n",
|
||||
__func__,
|
||||
tm->tm_sec, tm->tm_min, tm->tm_hour,
|
||||
tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
|
||||
|
||||
/* The clock can give out invalid datetime, but we cannot return
|
||||
* -EINVAL otherwise hwclock will refuse to set the time on bootup. */
|
||||
if (rtc_valid_tm(tm) < 0)
|
||||
dev_err(&client->dev, "retrieved date and time is invalid.\n");
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int isl12022_set_datetime(struct i2c_client *client, struct rtc_time *tm)
|
||||
{
|
||||
struct isl12022 *isl12022 = i2c_get_clientdata(client);
|
||||
size_t i;
|
||||
int ret;
|
||||
uint8_t buf[ISL12022_REG_DW + 1];
|
||||
|
||||
dev_dbg(&client->dev, "%s: secs=%d, mins=%d, hours=%d, "
|
||||
"mday=%d, mon=%d, year=%d, wday=%d\n",
|
||||
__func__,
|
||||
tm->tm_sec, tm->tm_min, tm->tm_hour,
|
||||
tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
|
||||
|
||||
if (!isl12022->write_enabled) {
|
||||
|
||||
ret = isl12022_read_regs(client, ISL12022_REG_INT, buf, 1);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
/* Check if WRTC (write rtc enable) is set factory default is
|
||||
* 0 (not set) */
|
||||
if (!(buf[0] & ISL12022_INT_WRTC)) {
|
||||
dev_info(&client->dev,
|
||||
"init write enable and 24 hour format\n");
|
||||
|
||||
/* Set the write enable bit. */
|
||||
ret = isl12022_write_reg(client,
|
||||
ISL12022_REG_INT,
|
||||
buf[0] | ISL12022_INT_WRTC);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
/* Write to any RTC register to start RTC, we use the
|
||||
* HR register, setting the MIL bit to use the 24 hour
|
||||
* format. */
|
||||
ret = isl12022_read_regs(client, ISL12022_REG_HR,
|
||||
buf, 1);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
ret = isl12022_write_reg(client,
|
||||
ISL12022_REG_HR,
|
||||
buf[0] | ISL12022_HR_MIL);
|
||||
if (ret)
|
||||
return ret;
|
||||
}
|
||||
|
||||
isl12022->write_enabled = 1;
|
||||
}
|
||||
|
||||
/* hours, minutes and seconds */
|
||||
buf[ISL12022_REG_SC] = bin2bcd(tm->tm_sec);
|
||||
buf[ISL12022_REG_MN] = bin2bcd(tm->tm_min);
|
||||
buf[ISL12022_REG_HR] = bin2bcd(tm->tm_hour);
|
||||
|
||||
buf[ISL12022_REG_DT] = bin2bcd(tm->tm_mday);
|
||||
|
||||
/* month, 1 - 12 */
|
||||
buf[ISL12022_REG_MO] = bin2bcd(tm->tm_mon + 1);
|
||||
|
||||
/* year and century */
|
||||
buf[ISL12022_REG_YR] = bin2bcd(tm->tm_year % 100);
|
||||
|
||||
buf[ISL12022_REG_DW] = tm->tm_wday & 0x07;
|
||||
|
||||
/* write register's data */
|
||||
for (i = 0; i < ARRAY_SIZE(buf); i++) {
|
||||
ret = isl12022_write_reg(client, ISL12022_REG_SC + i,
|
||||
buf[ISL12022_REG_SC + i]);
|
||||
if (ret)
|
||||
return -EIO;
|
||||
};
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int isl12022_rtc_read_time(struct device *dev, struct rtc_time *tm)
|
||||
{
|
||||
return isl12022_get_datetime(to_i2c_client(dev), tm);
|
||||
}
|
||||
|
||||
static int isl12022_rtc_set_time(struct device *dev, struct rtc_time *tm)
|
||||
{
|
||||
return isl12022_set_datetime(to_i2c_client(dev), tm);
|
||||
}
|
||||
|
||||
static const struct rtc_class_ops isl12022_rtc_ops = {
|
||||
.read_time = isl12022_rtc_read_time,
|
||||
.set_time = isl12022_rtc_set_time,
|
||||
};
|
||||
|
||||
static int isl12022_probe(struct i2c_client *client,
|
||||
const struct i2c_device_id *id)
|
||||
{
|
||||
struct isl12022 *isl12022;
|
||||
|
||||
int ret = 0;
|
||||
|
||||
if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
|
||||
return -ENODEV;
|
||||
|
||||
isl12022 = kzalloc(sizeof(struct isl12022), GFP_KERNEL);
|
||||
if (!isl12022)
|
||||
return -ENOMEM;
|
||||
|
||||
dev_dbg(&client->dev, "chip found, driver version " DRV_VERSION "\n");
|
||||
|
||||
i2c_set_clientdata(client, isl12022);
|
||||
|
||||
isl12022->rtc = rtc_device_register(isl12022_driver.driver.name,
|
||||
&client->dev,
|
||||
&isl12022_rtc_ops,
|
||||
THIS_MODULE);
|
||||
|
||||
if (IS_ERR(isl12022->rtc)) {
|
||||
ret = PTR_ERR(isl12022->rtc);
|
||||
goto exit_kfree;
|
||||
}
|
||||
|
||||
return 0;
|
||||
|
||||
exit_kfree:
|
||||
kfree(isl12022);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int isl12022_remove(struct i2c_client *client)
|
||||
{
|
||||
struct isl12022 *isl12022 = i2c_get_clientdata(client);
|
||||
|
||||
rtc_device_unregister(isl12022->rtc);
|
||||
kfree(isl12022);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static const struct i2c_device_id isl12022_id[] = {
|
||||
{ "isl12022", 0 },
|
||||
{ "rtc8564", 0 },
|
||||
{ }
|
||||
};
|
||||
MODULE_DEVICE_TABLE(i2c, isl12022_id);
|
||||
|
||||
static struct i2c_driver isl12022_driver = {
|
||||
.driver = {
|
||||
.name = "rtc-isl12022",
|
||||
},
|
||||
.probe = isl12022_probe,
|
||||
.remove = isl12022_remove,
|
||||
.id_table = isl12022_id,
|
||||
};
|
||||
|
||||
static int __init isl12022_init(void)
|
||||
{
|
||||
return i2c_add_driver(&isl12022_driver);
|
||||
}
|
||||
|
||||
static void __exit isl12022_exit(void)
|
||||
{
|
||||
i2c_del_driver(&isl12022_driver);
|
||||
}
|
||||
|
||||
module_init(isl12022_init);
|
||||
module_exit(isl12022_exit);
|
||||
|
||||
MODULE_AUTHOR("roman.fietze@telemotive.de");
|
||||
MODULE_DESCRIPTION("ISL 12022 RTC driver");
|
||||
MODULE_LICENSE("GPL");
|
||||
MODULE_VERSION(DRV_VERSION);
|
||||
Loading…
Reference in New Issue