drivers/rtc/rtc-s35390a.c: add wakealarm support for rtc-s35390A rtc chip

Add basic get/set alarm support for the Seiko Instruments S-35390A.  The
chip is used on the QNAP TS-219P+ NAS device.

Signed-off-by: Michael Langer <michael.brainbug.langer@googlemail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Michael Langer 2012-10-04 17:14:37 -07:00 committed by Linus Torvalds
parent 48e9766726
commit 542dd33a49

View File

@ -19,6 +19,8 @@
#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
@ -28,12 +30,23 @@
#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
#define S35390A_FLAG_POC 0x01
#define S35390A_FLAG_BLD 0x02
#define S35390A_FLAG_24H 0x40
#define S35390A_FLAG_RESET 0x80
#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 },
{ }
@ -193,6 +206,104 @@ static int s35390a_get_datetime(struct i2c_client *client, struct rtc_time *tm)
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 */
err = s35390a_set_reg(s35390a, S35390A_CMD_STATUS2, &sts, sizeof(sts));
if (err < 0)
return err;
/* clear pending interrupt, 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;
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_ALARM)
return -EINVAL;
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]);
buf[i] &= ~0x80;
}
alm->time.tm_wday = bcd2bin(buf[S35390A_ALRM_BYTE_WDAY]);
alm->time.tm_hour = s35390a_reg2hr(s35390a,
buf[S35390A_ALRM_BYTE_HOURS]);
alm->time.tm_min = bcd2bin(buf[S35390A_ALRM_BYTE_MINS]);
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);
@ -206,6 +317,9 @@ static int s35390a_rtc_set_time(struct device *dev, struct rtc_time *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;
@ -270,6 +384,8 @@ static int s35390a_probe(struct i2c_client *client,
if (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 = rtc_device_register(s35390a_driver.driver.name,
&client->dev, &s35390a_rtc_ops, THIS_MODULE);