mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-25 10:19:47 +00:00
![Javier Martinez Canillas](/assets/img/avatar_default.png)
The driver doesn't have a struct of_device_id table but supported devices are registered via Device Trees. This is working on the assumption that a I2C device registered via OF will always match a legacy I2C device ID and that the MODALIAS reported will always be of the form i2c:<device>. But this could change in the future so the correct approach is to have an OF device ID table if the devices are registered via OF. Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
523 lines
13 KiB
C
523 lines
13 KiB
C
/*
|
|
* Seiko Instruments S-35390A RTC Driver
|
|
*
|
|
* Copyright (c) 2007 Byron Bradley
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation; either version
|
|
* 2 of the License, or (at your option) any later version.
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/rtc.h>
|
|
#include <linux/i2c.h>
|
|
#include <linux/bitrev.h>
|
|
#include <linux/bcd.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/delay.h>
|
|
|
|
#define S35390A_CMD_STATUS1 0
|
|
#define S35390A_CMD_STATUS2 1
|
|
#define S35390A_CMD_TIME1 2
|
|
#define S35390A_CMD_TIME2 3
|
|
#define S35390A_CMD_INT2_REG1 5
|
|
|
|
#define S35390A_BYTE_YEAR 0
|
|
#define S35390A_BYTE_MONTH 1
|
|
#define S35390A_BYTE_DAY 2
|
|
#define S35390A_BYTE_WDAY 3
|
|
#define S35390A_BYTE_HOURS 4
|
|
#define S35390A_BYTE_MINS 5
|
|
#define S35390A_BYTE_SECS 6
|
|
|
|
#define S35390A_ALRM_BYTE_WDAY 0
|
|
#define S35390A_ALRM_BYTE_HOURS 1
|
|
#define S35390A_ALRM_BYTE_MINS 2
|
|
|
|
/* flags for STATUS1 */
|
|
#define S35390A_FLAG_POC 0x01
|
|
#define S35390A_FLAG_BLD 0x02
|
|
#define S35390A_FLAG_INT2 0x04
|
|
#define S35390A_FLAG_24H 0x40
|
|
#define S35390A_FLAG_RESET 0x80
|
|
|
|
/* flag for STATUS2 */
|
|
#define S35390A_FLAG_TEST 0x01
|
|
|
|
#define S35390A_INT2_MODE_MASK 0xF0
|
|
|
|
#define S35390A_INT2_MODE_NOINTR 0x00
|
|
#define S35390A_INT2_MODE_FREQ 0x10
|
|
#define S35390A_INT2_MODE_ALARM 0x40
|
|
#define S35390A_INT2_MODE_PMIN_EDG 0x20
|
|
|
|
static const struct i2c_device_id s35390a_id[] = {
|
|
{ "s35390a", 0 },
|
|
{ }
|
|
};
|
|
MODULE_DEVICE_TABLE(i2c, s35390a_id);
|
|
|
|
static const struct of_device_id s35390a_of_match[] = {
|
|
{ .compatible = "s35390a" },
|
|
{ .compatible = "sii,s35390a" },
|
|
{ }
|
|
};
|
|
MODULE_DEVICE_TABLE(of, s35390a_of_match);
|
|
|
|
struct s35390a {
|
|
struct i2c_client *client[8];
|
|
struct rtc_device *rtc;
|
|
int twentyfourhour;
|
|
};
|
|
|
|
static int s35390a_set_reg(struct s35390a *s35390a, int reg, char *buf, int len)
|
|
{
|
|
struct i2c_client *client = s35390a->client[reg];
|
|
struct i2c_msg msg[] = {
|
|
{
|
|
.addr = client->addr,
|
|
.len = len,
|
|
.buf = buf
|
|
},
|
|
};
|
|
|
|
if ((i2c_transfer(client->adapter, msg, 1)) != 1)
|
|
return -EIO;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int s35390a_get_reg(struct s35390a *s35390a, int reg, char *buf, int len)
|
|
{
|
|
struct i2c_client *client = s35390a->client[reg];
|
|
struct i2c_msg msg[] = {
|
|
{
|
|
.addr = client->addr,
|
|
.flags = I2C_M_RD,
|
|
.len = len,
|
|
.buf = buf
|
|
},
|
|
};
|
|
|
|
if ((i2c_transfer(client->adapter, msg, 1)) != 1)
|
|
return -EIO;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Returns <0 on error, 0 if rtc is setup fine and 1 if the chip was reset.
|
|
* To keep the information if an irq is pending, pass the value read from
|
|
* STATUS1 to the caller.
|
|
*/
|
|
static int s35390a_reset(struct s35390a *s35390a, char *status1)
|
|
{
|
|
char buf;
|
|
int ret;
|
|
unsigned initcount = 0;
|
|
|
|
ret = s35390a_get_reg(s35390a, S35390A_CMD_STATUS1, status1, 1);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
if (*status1 & S35390A_FLAG_POC)
|
|
/*
|
|
* Do not communicate for 0.5 seconds since the power-on
|
|
* detection circuit is in operation.
|
|
*/
|
|
msleep(500);
|
|
else if (!(*status1 & S35390A_FLAG_BLD))
|
|
/*
|
|
* If both POC and BLD are unset everything is fine.
|
|
*/
|
|
return 0;
|
|
|
|
/*
|
|
* At least one of POC and BLD are set, so reinitialise chip. Keeping
|
|
* this information in the hardware to know later that the time isn't
|
|
* valid is unfortunately not possible because POC and BLD are cleared
|
|
* on read. So the reset is best done now.
|
|
*
|
|
* The 24H bit is kept over reset, so set it already here.
|
|
*/
|
|
initialize:
|
|
*status1 = S35390A_FLAG_24H;
|
|
buf = S35390A_FLAG_RESET | S35390A_FLAG_24H;
|
|
ret = s35390a_set_reg(s35390a, S35390A_CMD_STATUS1, &buf, 1);
|
|
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
ret = s35390a_get_reg(s35390a, S35390A_CMD_STATUS1, &buf, 1);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
if (buf & (S35390A_FLAG_POC | S35390A_FLAG_BLD)) {
|
|
/* Try up to five times to reset the chip */
|
|
if (initcount < 5) {
|
|
++initcount;
|
|
goto initialize;
|
|
} else
|
|
return -EIO;
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
static int s35390a_disable_test_mode(struct s35390a *s35390a)
|
|
{
|
|
char buf[1];
|
|
|
|
if (s35390a_get_reg(s35390a, S35390A_CMD_STATUS2, buf, sizeof(buf)) < 0)
|
|
return -EIO;
|
|
|
|
if (!(buf[0] & S35390A_FLAG_TEST))
|
|
return 0;
|
|
|
|
buf[0] &= ~S35390A_FLAG_TEST;
|
|
return s35390a_set_reg(s35390a, S35390A_CMD_STATUS2, buf, sizeof(buf));
|
|
}
|
|
|
|
static char s35390a_hr2reg(struct s35390a *s35390a, int hour)
|
|
{
|
|
if (s35390a->twentyfourhour)
|
|
return bin2bcd(hour);
|
|
|
|
if (hour < 12)
|
|
return bin2bcd(hour);
|
|
|
|
return 0x40 | bin2bcd(hour - 12);
|
|
}
|
|
|
|
static int s35390a_reg2hr(struct s35390a *s35390a, char reg)
|
|
{
|
|
unsigned hour;
|
|
|
|
if (s35390a->twentyfourhour)
|
|
return bcd2bin(reg & 0x3f);
|
|
|
|
hour = bcd2bin(reg & 0x3f);
|
|
if (reg & 0x40)
|
|
hour += 12;
|
|
|
|
return hour;
|
|
}
|
|
|
|
static int s35390a_set_datetime(struct i2c_client *client, struct rtc_time *tm)
|
|
{
|
|
struct s35390a *s35390a = i2c_get_clientdata(client);
|
|
int i, err;
|
|
char buf[7];
|
|
|
|
dev_dbg(&client->dev, "%s: tm is 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);
|
|
|
|
buf[S35390A_BYTE_YEAR] = bin2bcd(tm->tm_year - 100);
|
|
buf[S35390A_BYTE_MONTH] = bin2bcd(tm->tm_mon + 1);
|
|
buf[S35390A_BYTE_DAY] = bin2bcd(tm->tm_mday);
|
|
buf[S35390A_BYTE_WDAY] = bin2bcd(tm->tm_wday);
|
|
buf[S35390A_BYTE_HOURS] = s35390a_hr2reg(s35390a, tm->tm_hour);
|
|
buf[S35390A_BYTE_MINS] = bin2bcd(tm->tm_min);
|
|
buf[S35390A_BYTE_SECS] = bin2bcd(tm->tm_sec);
|
|
|
|
/* This chip expects the bits of each byte to be in reverse order */
|
|
for (i = 0; i < 7; ++i)
|
|
buf[i] = bitrev8(buf[i]);
|
|
|
|
err = s35390a_set_reg(s35390a, S35390A_CMD_TIME1, buf, sizeof(buf));
|
|
|
|
return err;
|
|
}
|
|
|
|
static int s35390a_get_datetime(struct i2c_client *client, struct rtc_time *tm)
|
|
{
|
|
struct s35390a *s35390a = i2c_get_clientdata(client);
|
|
char buf[7];
|
|
int i, err;
|
|
|
|
err = s35390a_get_reg(s35390a, S35390A_CMD_TIME1, buf, sizeof(buf));
|
|
if (err < 0)
|
|
return err;
|
|
|
|
/* This chip returns the bits of each byte in reverse order */
|
|
for (i = 0; i < 7; ++i)
|
|
buf[i] = bitrev8(buf[i]);
|
|
|
|
tm->tm_sec = bcd2bin(buf[S35390A_BYTE_SECS]);
|
|
tm->tm_min = bcd2bin(buf[S35390A_BYTE_MINS]);
|
|
tm->tm_hour = s35390a_reg2hr(s35390a, buf[S35390A_BYTE_HOURS]);
|
|
tm->tm_wday = bcd2bin(buf[S35390A_BYTE_WDAY]);
|
|
tm->tm_mday = bcd2bin(buf[S35390A_BYTE_DAY]);
|
|
tm->tm_mon = bcd2bin(buf[S35390A_BYTE_MONTH]) - 1;
|
|
tm->tm_year = bcd2bin(buf[S35390A_BYTE_YEAR]) + 100;
|
|
|
|
dev_dbg(&client->dev, "%s: tm is 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);
|
|
|
|
return rtc_valid_tm(tm);
|
|
}
|
|
|
|
static int s35390a_set_alarm(struct i2c_client *client, struct rtc_wkalrm *alm)
|
|
{
|
|
struct s35390a *s35390a = i2c_get_clientdata(client);
|
|
char buf[3], sts = 0;
|
|
int err, i;
|
|
|
|
dev_dbg(&client->dev, "%s: alm is secs=%d, mins=%d, hours=%d mday=%d, "\
|
|
"mon=%d, year=%d, wday=%d\n", __func__, alm->time.tm_sec,
|
|
alm->time.tm_min, alm->time.tm_hour, alm->time.tm_mday,
|
|
alm->time.tm_mon, alm->time.tm_year, alm->time.tm_wday);
|
|
|
|
/* disable interrupt (which deasserts the irq line) */
|
|
err = s35390a_set_reg(s35390a, S35390A_CMD_STATUS2, &sts, sizeof(sts));
|
|
if (err < 0)
|
|
return err;
|
|
|
|
/* clear pending interrupt (in STATUS1 only), if any */
|
|
err = s35390a_get_reg(s35390a, S35390A_CMD_STATUS1, &sts, sizeof(sts));
|
|
if (err < 0)
|
|
return err;
|
|
|
|
if (alm->enabled)
|
|
sts = S35390A_INT2_MODE_ALARM;
|
|
else
|
|
sts = S35390A_INT2_MODE_NOINTR;
|
|
|
|
/* This chip expects the bits of each byte to be in reverse order */
|
|
sts = bitrev8(sts);
|
|
|
|
/* set interupt mode*/
|
|
err = s35390a_set_reg(s35390a, S35390A_CMD_STATUS2, &sts, sizeof(sts));
|
|
if (err < 0)
|
|
return err;
|
|
|
|
if (alm->time.tm_wday != -1)
|
|
buf[S35390A_ALRM_BYTE_WDAY] = bin2bcd(alm->time.tm_wday) | 0x80;
|
|
else
|
|
buf[S35390A_ALRM_BYTE_WDAY] = 0;
|
|
|
|
buf[S35390A_ALRM_BYTE_HOURS] = s35390a_hr2reg(s35390a,
|
|
alm->time.tm_hour) | 0x80;
|
|
buf[S35390A_ALRM_BYTE_MINS] = bin2bcd(alm->time.tm_min) | 0x80;
|
|
|
|
if (alm->time.tm_hour >= 12)
|
|
buf[S35390A_ALRM_BYTE_HOURS] |= 0x40;
|
|
|
|
for (i = 0; i < 3; ++i)
|
|
buf[i] = bitrev8(buf[i]);
|
|
|
|
err = s35390a_set_reg(s35390a, S35390A_CMD_INT2_REG1, buf,
|
|
sizeof(buf));
|
|
|
|
return err;
|
|
}
|
|
|
|
static int s35390a_read_alarm(struct i2c_client *client, struct rtc_wkalrm *alm)
|
|
{
|
|
struct s35390a *s35390a = i2c_get_clientdata(client);
|
|
char buf[3], sts;
|
|
int i, err;
|
|
|
|
err = s35390a_get_reg(s35390a, S35390A_CMD_STATUS2, &sts, sizeof(sts));
|
|
if (err < 0)
|
|
return err;
|
|
|
|
if ((bitrev8(sts) & S35390A_INT2_MODE_MASK) != S35390A_INT2_MODE_ALARM) {
|
|
/*
|
|
* When the alarm isn't enabled, the register to configure
|
|
* the alarm time isn't accessible.
|
|
*/
|
|
alm->enabled = 0;
|
|
return 0;
|
|
} else {
|
|
alm->enabled = 1;
|
|
}
|
|
|
|
err = s35390a_get_reg(s35390a, S35390A_CMD_INT2_REG1, buf, sizeof(buf));
|
|
if (err < 0)
|
|
return err;
|
|
|
|
/* This chip returns the bits of each byte in reverse order */
|
|
for (i = 0; i < 3; ++i)
|
|
buf[i] = bitrev8(buf[i]);
|
|
|
|
/*
|
|
* B0 of the three matching registers is an enable flag. Iff it is set
|
|
* the configured value is used for matching.
|
|
*/
|
|
if (buf[S35390A_ALRM_BYTE_WDAY] & 0x80)
|
|
alm->time.tm_wday =
|
|
bcd2bin(buf[S35390A_ALRM_BYTE_WDAY] & ~0x80);
|
|
|
|
if (buf[S35390A_ALRM_BYTE_HOURS] & 0x80)
|
|
alm->time.tm_hour =
|
|
s35390a_reg2hr(s35390a,
|
|
buf[S35390A_ALRM_BYTE_HOURS] & ~0x80);
|
|
|
|
if (buf[S35390A_ALRM_BYTE_MINS] & 0x80)
|
|
alm->time.tm_min = bcd2bin(buf[S35390A_ALRM_BYTE_MINS] & ~0x80);
|
|
|
|
/* alarm triggers always at s=0 */
|
|
alm->time.tm_sec = 0;
|
|
|
|
dev_dbg(&client->dev, "%s: alm is mins=%d, hours=%d, wday=%d\n",
|
|
__func__, alm->time.tm_min, alm->time.tm_hour,
|
|
alm->time.tm_wday);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int s35390a_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
|
|
{
|
|
return s35390a_read_alarm(to_i2c_client(dev), alm);
|
|
}
|
|
|
|
static int s35390a_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
|
|
{
|
|
return s35390a_set_alarm(to_i2c_client(dev), alm);
|
|
}
|
|
|
|
static int s35390a_rtc_read_time(struct device *dev, struct rtc_time *tm)
|
|
{
|
|
return s35390a_get_datetime(to_i2c_client(dev), tm);
|
|
}
|
|
|
|
static int s35390a_rtc_set_time(struct device *dev, struct rtc_time *tm)
|
|
{
|
|
return s35390a_set_datetime(to_i2c_client(dev), tm);
|
|
}
|
|
|
|
static const struct rtc_class_ops s35390a_rtc_ops = {
|
|
.read_time = s35390a_rtc_read_time,
|
|
.set_time = s35390a_rtc_set_time,
|
|
.set_alarm = s35390a_rtc_set_alarm,
|
|
.read_alarm = s35390a_rtc_read_alarm,
|
|
|
|
};
|
|
|
|
static struct i2c_driver s35390a_driver;
|
|
|
|
static int s35390a_probe(struct i2c_client *client,
|
|
const struct i2c_device_id *id)
|
|
{
|
|
int err, err_reset;
|
|
unsigned int i;
|
|
struct s35390a *s35390a;
|
|
struct rtc_time tm;
|
|
char buf, status1;
|
|
|
|
if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
|
|
err = -ENODEV;
|
|
goto exit;
|
|
}
|
|
|
|
s35390a = devm_kzalloc(&client->dev, sizeof(struct s35390a),
|
|
GFP_KERNEL);
|
|
if (!s35390a) {
|
|
err = -ENOMEM;
|
|
goto exit;
|
|
}
|
|
|
|
s35390a->client[0] = client;
|
|
i2c_set_clientdata(client, s35390a);
|
|
|
|
/* This chip uses multiple addresses, use dummy devices for them */
|
|
for (i = 1; i < 8; ++i) {
|
|
s35390a->client[i] = i2c_new_dummy(client->adapter,
|
|
client->addr + i);
|
|
if (!s35390a->client[i]) {
|
|
dev_err(&client->dev, "Address %02x unavailable\n",
|
|
client->addr + i);
|
|
err = -EBUSY;
|
|
goto exit_dummy;
|
|
}
|
|
}
|
|
|
|
err_reset = s35390a_reset(s35390a, &status1);
|
|
if (err_reset < 0) {
|
|
err = err_reset;
|
|
dev_err(&client->dev, "error resetting chip\n");
|
|
goto exit_dummy;
|
|
}
|
|
|
|
if (status1 & S35390A_FLAG_24H)
|
|
s35390a->twentyfourhour = 1;
|
|
else
|
|
s35390a->twentyfourhour = 0;
|
|
|
|
if (status1 & S35390A_FLAG_INT2) {
|
|
/* disable alarm (and maybe test mode) */
|
|
buf = 0;
|
|
err = s35390a_set_reg(s35390a, S35390A_CMD_STATUS2, &buf, 1);
|
|
if (err < 0) {
|
|
dev_err(&client->dev, "error disabling alarm");
|
|
goto exit_dummy;
|
|
}
|
|
} else {
|
|
err = s35390a_disable_test_mode(s35390a);
|
|
if (err < 0) {
|
|
dev_err(&client->dev, "error disabling test mode\n");
|
|
goto exit_dummy;
|
|
}
|
|
}
|
|
|
|
if (err_reset > 0 || s35390a_get_datetime(client, &tm) < 0)
|
|
dev_warn(&client->dev, "clock needs to be set\n");
|
|
|
|
device_set_wakeup_capable(&client->dev, 1);
|
|
|
|
s35390a->rtc = devm_rtc_device_register(&client->dev,
|
|
s35390a_driver.driver.name,
|
|
&s35390a_rtc_ops, THIS_MODULE);
|
|
|
|
if (IS_ERR(s35390a->rtc)) {
|
|
err = PTR_ERR(s35390a->rtc);
|
|
goto exit_dummy;
|
|
}
|
|
|
|
if (status1 & S35390A_FLAG_INT2)
|
|
rtc_update_irq(s35390a->rtc, 1, RTC_AF);
|
|
|
|
return 0;
|
|
|
|
exit_dummy:
|
|
for (i = 1; i < 8; ++i)
|
|
if (s35390a->client[i])
|
|
i2c_unregister_device(s35390a->client[i]);
|
|
|
|
exit:
|
|
return err;
|
|
}
|
|
|
|
static int s35390a_remove(struct i2c_client *client)
|
|
{
|
|
unsigned int i;
|
|
struct s35390a *s35390a = i2c_get_clientdata(client);
|
|
|
|
for (i = 1; i < 8; ++i)
|
|
if (s35390a->client[i])
|
|
i2c_unregister_device(s35390a->client[i]);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct i2c_driver s35390a_driver = {
|
|
.driver = {
|
|
.name = "rtc-s35390a",
|
|
.of_match_table = of_match_ptr(s35390a_of_match),
|
|
},
|
|
.probe = s35390a_probe,
|
|
.remove = s35390a_remove,
|
|
.id_table = s35390a_id,
|
|
};
|
|
|
|
module_i2c_driver(s35390a_driver);
|
|
|
|
MODULE_AUTHOR("Byron Bradley <byron.bbradley@gmail.com>");
|
|
MODULE_DESCRIPTION("S35390A RTC driver");
|
|
MODULE_LICENSE("GPL");
|