drivers/rtc/rtc-ds3232.c: add alarm function
The DS3232 RTC driver only has the tick function. Add an alarm function
so the driver is complete.
Signed-off-by: Lan Chunhe-B25806 <b25806@freescale.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Wan ZongShun <mcuos.com@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/rtc/rtc-ds3232.c b/drivers/rtc/rtc-ds3232.c
index 9de8516..5706355 100644
--- a/drivers/rtc/rtc-ds3232.c
+++ b/drivers/rtc/rtc-ds3232.c
@@ -2,6 +2,7 @@
* RTC client/driver for the Maxim/Dallas DS3232 Real-Time Clock over I2C
*
* Copyright (C) 2009-2010 Freescale Semiconductor.
+ * Author: Jack Lan <jack.lan@freescale.com>
*
* 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
@@ -175,6 +176,182 @@
DS3232_REG_SECONDS, 7, buf);
}
+/*
+ * DS3232 has two alarm, we only use alarm1
+ * According to linux specification, only support one-shot alarm
+ * no periodic alarm mode
+ */
+static int ds3232_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct ds3232 *ds3232 = i2c_get_clientdata(client);
+ int control, stat;
+ int ret;
+ u8 buf[4];
+
+ mutex_lock(&ds3232->mutex);
+
+ ret = i2c_smbus_read_byte_data(client, DS3232_REG_SR);
+ if (ret < 0)
+ goto out;
+ stat = ret;
+ ret = i2c_smbus_read_byte_data(client, DS3232_REG_CR);
+ if (ret < 0)
+ goto out;
+ control = ret;
+ ret = i2c_smbus_read_i2c_block_data(client, DS3232_REG_ALARM1, 4, buf);
+ if (ret < 0)
+ goto out;
+
+ alarm->time.tm_sec = bcd2bin(buf[0] & 0x7F);
+ alarm->time.tm_min = bcd2bin(buf[1] & 0x7F);
+ alarm->time.tm_hour = bcd2bin(buf[2] & 0x7F);
+ alarm->time.tm_mday = bcd2bin(buf[3] & 0x7F);
+
+ 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;
+
+ alarm->enabled = !!(control & DS3232_REG_CR_A1IE);
+ alarm->pending = !!(stat & DS3232_REG_SR_A1F);
+
+ ret = 0;
+out:
+ mutex_unlock(&ds3232->mutex);
+ return ret;
+}
+
+/*
+ * linux rtc-module does not support wday alarm
+ * and only 24h time mode supported indeed
+ */
+static int ds3232_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct ds3232 *ds3232 = i2c_get_clientdata(client);
+ int control, stat;
+ int ret;
+ u8 buf[4];
+
+ if (client->irq <= 0)
+ return -EINVAL;
+
+ mutex_lock(&ds3232->mutex);
+
+ buf[0] = bin2bcd(alarm->time.tm_sec);
+ buf[1] = bin2bcd(alarm->time.tm_min);
+ buf[2] = bin2bcd(alarm->time.tm_hour);
+ buf[3] = bin2bcd(alarm->time.tm_mday);
+
+ /* clear alarm interrupt enable bit */
+ ret = i2c_smbus_read_byte_data(client, DS3232_REG_CR);
+ if (ret < 0)
+ goto out;
+ control = ret;
+ control &= ~(DS3232_REG_CR_A1IE | DS3232_REG_CR_A2IE);
+ ret = i2c_smbus_write_byte_data(client, DS3232_REG_CR, control);
+ if (ret < 0)
+ goto out;
+
+ /* clear any pending alarm flag */
+ ret = i2c_smbus_read_byte_data(client, DS3232_REG_SR);
+ if (ret < 0)
+ goto out;
+ stat = ret;
+ stat &= ~(DS3232_REG_SR_A1F | DS3232_REG_SR_A2F);
+ ret = i2c_smbus_write_byte_data(client, DS3232_REG_SR, stat);
+ if (ret < 0)
+ goto out;
+
+ ret = i2c_smbus_write_i2c_block_data(client, DS3232_REG_ALARM1, 4, buf);
+
+ if (alarm->enabled) {
+ control |= DS3232_REG_CR_A1IE;
+ ret = i2c_smbus_write_byte_data(client, DS3232_REG_CR, control);
+ }
+out:
+ mutex_unlock(&ds3232->mutex);
+ return ret;
+}
+
+static void ds3232_update_alarm(struct i2c_client *client)
+{
+ struct ds3232 *ds3232 = i2c_get_clientdata(client);
+ int control;
+ int ret;
+ u8 buf[4];
+
+ mutex_lock(&ds3232->mutex);
+
+ ret = i2c_smbus_read_i2c_block_data(client, DS3232_REG_ALARM1, 4, buf);
+ if (ret < 0)
+ goto unlock;
+
+ buf[0] = bcd2bin(buf[0]) < 0 || (ds3232->rtc->irq_data & RTC_UF) ?
+ 0x80 : buf[0];
+ buf[1] = bcd2bin(buf[1]) < 0 || (ds3232->rtc->irq_data & RTC_UF) ?
+ 0x80 : buf[1];
+ buf[2] = bcd2bin(buf[2]) < 0 || (ds3232->rtc->irq_data & RTC_UF) ?
+ 0x80 : buf[2];
+ buf[3] = bcd2bin(buf[3]) < 0 || (ds3232->rtc->irq_data & RTC_UF) ?
+ 0x80 : buf[3];
+
+ ret = i2c_smbus_write_i2c_block_data(client, DS3232_REG_ALARM1, 4, buf);
+ if (ret < 0)
+ goto unlock;
+
+ control = i2c_smbus_read_byte_data(client, DS3232_REG_CR);
+ if (control < 0)
+ goto unlock;
+
+ if (ds3232->rtc->irq_data & (RTC_AF | RTC_UF))
+ /* enable alarm1 interrupt */
+ control |= DS3232_REG_CR_A1IE;
+ else
+ /* disable alarm1 interrupt */
+ control &= ~(DS3232_REG_CR_A1IE);
+ i2c_smbus_write_byte_data(client, DS3232_REG_CR, control);
+
+unlock:
+ mutex_unlock(&ds3232->mutex);
+}
+
+static int ds3232_alarm_irq_enable(struct device *dev, unsigned int enabled)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct ds3232 *ds3232 = i2c_get_clientdata(client);
+
+ if (client->irq <= 0)
+ return -EINVAL;
+
+ if (enabled)
+ ds3232->rtc->irq_data |= RTC_AF;
+ else
+ ds3232->rtc->irq_data &= ~RTC_AF;
+
+ ds3232_update_alarm(client);
+ return 0;
+}
+
+static int ds3232_update_irq_enable(struct device *dev, unsigned int enabled)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct ds3232 *ds3232 = i2c_get_clientdata(client);
+
+ if (client->irq <= 0)
+ return -EINVAL;
+
+ if (enabled)
+ ds3232->rtc->irq_data |= RTC_UF;
+ else
+ ds3232->rtc->irq_data &= ~RTC_UF;
+
+ ds3232_update_alarm(client);
+ return 0;
+}
+
static irqreturn_t ds3232_irq(int irq, void *dev_id)
{
struct i2c_client *client = dev_id;
@@ -222,6 +399,10 @@
static const struct rtc_class_ops ds3232_rtc_ops = {
.read_time = ds3232_read_time,
.set_time = ds3232_set_time,
+ .read_alarm = ds3232_read_alarm,
+ .set_alarm = ds3232_set_alarm,
+ .alarm_irq_enable = ds3232_alarm_irq_enable,
+ .update_irq_enable = ds3232_update_irq_enable,
};
static int __devinit ds3232_probe(struct i2c_client *client,