summaryrefslogtreecommitdiff
path: root/drivers/rtc/rtc-isl12057.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/rtc/rtc-isl12057.c')
-rw-r--r--drivers/rtc/rtc-isl12057.c351
1 files changed, 341 insertions, 10 deletions
diff --git a/drivers/rtc/rtc-isl12057.c b/drivers/rtc/rtc-isl12057.c
index 6e1fcfb5d7e6..da818d3337ce 100644
--- a/drivers/rtc/rtc-isl12057.c
+++ b/drivers/rtc/rtc-isl12057.c
@@ -79,8 +79,10 @@
#define ISL12057_MEM_MAP_LEN 0x10
struct isl12057_rtc_data {
+ struct rtc_device *rtc;
struct regmap *regmap;
struct mutex lock;
+ int irq;
};
static void isl12057_rtc_regs_to_tm(struct rtc_time *tm, u8 *regs)
@@ -160,14 +162,47 @@ static int isl12057_i2c_validate_chip(struct regmap *regmap)
return 0;
}
-static int isl12057_rtc_read_time(struct device *dev, struct rtc_time *tm)
+static int _isl12057_rtc_clear_alarm(struct device *dev)
+{
+ struct isl12057_rtc_data *data = dev_get_drvdata(dev);
+ int ret;
+
+ ret = regmap_update_bits(data->regmap, ISL12057_REG_SR,
+ ISL12057_REG_SR_A1F, 0);
+ if (ret)
+ dev_err(dev, "%s: clearing alarm failed (%d)\n", __func__, ret);
+
+ return ret;
+}
+
+static int _isl12057_rtc_update_alarm(struct device *dev, int enable)
+{
+ struct isl12057_rtc_data *data = dev_get_drvdata(dev);
+ int ret;
+
+ ret = regmap_update_bits(data->regmap, ISL12057_REG_INT,
+ ISL12057_REG_INT_A1IE,
+ enable ? ISL12057_REG_INT_A1IE : 0);
+ if (ret)
+ dev_err(dev, "%s: changing alarm interrupt flag failed (%d)\n",
+ __func__, ret);
+
+ return ret;
+}
+
+/*
+ * Note: as we only read from device and do not perform any update, there is
+ * no need for an equivalent function which would try and get driver's main
+ * lock. Here, it is safe for everyone if we just use regmap internal lock
+ * on the device when reading.
+ */
+static int _isl12057_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
struct isl12057_rtc_data *data = dev_get_drvdata(dev);
u8 regs[ISL12057_RTC_SEC_LEN];
unsigned int sr;
int ret;
- mutex_lock(&data->lock);
ret = regmap_read(data->regmap, ISL12057_REG_SR, &sr);
if (ret) {
dev_err(dev, "%s: unable to read oscillator status flag (%d)\n",
@@ -187,8 +222,6 @@ static int isl12057_rtc_read_time(struct device *dev, struct rtc_time *tm)
__func__, ret);
out:
- mutex_unlock(&data->lock);
-
if (ret)
return ret;
@@ -197,6 +230,168 @@ out:
return rtc_valid_tm(tm);
}
+static int isl12057_rtc_update_alarm(struct device *dev, int enable)
+{
+ struct isl12057_rtc_data *data = dev_get_drvdata(dev);
+ int ret;
+
+ mutex_lock(&data->lock);
+ ret = _isl12057_rtc_update_alarm(dev, enable);
+ mutex_unlock(&data->lock);
+
+ return ret;
+}
+
+static int isl12057_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
+{
+ struct isl12057_rtc_data *data = dev_get_drvdata(dev);
+ struct rtc_time rtc_tm, *alarm_tm = &alarm->time;
+ unsigned long rtc_secs, alarm_secs;
+ u8 regs[ISL12057_A1_SEC_LEN];
+ unsigned int ir;
+ int ret;
+
+ mutex_lock(&data->lock);
+ ret = regmap_bulk_read(data->regmap, ISL12057_REG_A1_SC, regs,
+ ISL12057_A1_SEC_LEN);
+ if (ret) {
+ dev_err(dev, "%s: reading alarm section failed (%d)\n",
+ __func__, ret);
+ goto err_unlock;
+ }
+
+ alarm_tm->tm_sec = bcd2bin(regs[0] & 0x7f);
+ alarm_tm->tm_min = bcd2bin(regs[1] & 0x7f);
+ alarm_tm->tm_hour = bcd2bin(regs[2] & 0x3f);
+ alarm_tm->tm_mday = bcd2bin(regs[3] & 0x3f);
+ alarm_tm->tm_wday = -1;
+
+ /*
+ * The alarm section does not store year/month. We use the ones in rtc
+ * section as a basis and increment month and then year if needed to get
+ * alarm after current time.
+ */
+ ret = _isl12057_rtc_read_time(dev, &rtc_tm);
+ if (ret)
+ goto err_unlock;
+
+ alarm_tm->tm_year = rtc_tm.tm_year;
+ alarm_tm->tm_mon = rtc_tm.tm_mon;
+
+ ret = rtc_tm_to_time(&rtc_tm, &rtc_secs);
+ if (ret)
+ goto err_unlock;
+
+ ret = rtc_tm_to_time(alarm_tm, &alarm_secs);
+ if (ret)
+ goto err_unlock;
+
+ if (alarm_secs < rtc_secs) {
+ if (alarm_tm->tm_mon == 11) {
+ alarm_tm->tm_mon = 0;
+ alarm_tm->tm_year += 1;
+ } else {
+ alarm_tm->tm_mon += 1;
+ }
+ }
+
+ ret = regmap_read(data->regmap, ISL12057_REG_INT, &ir);
+ if (ret) {
+ dev_err(dev, "%s: reading alarm interrupt flag failed (%d)\n",
+ __func__, ret);
+ goto err_unlock;
+ }
+
+ alarm->enabled = !!(ir & ISL12057_REG_INT_A1IE);
+
+err_unlock:
+ mutex_unlock(&data->lock);
+
+ return ret;
+}
+
+static int isl12057_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
+{
+ struct isl12057_rtc_data *data = dev_get_drvdata(dev);
+ struct rtc_time *alarm_tm = &alarm->time;
+ unsigned long rtc_secs, alarm_secs;
+ u8 regs[ISL12057_A1_SEC_LEN];
+ struct rtc_time rtc_tm;
+ int ret, enable = 1;
+
+ mutex_lock(&data->lock);
+ ret = _isl12057_rtc_read_time(dev, &rtc_tm);
+ if (ret)
+ goto err_unlock;
+
+ ret = rtc_tm_to_time(&rtc_tm, &rtc_secs);
+ if (ret)
+ goto err_unlock;
+
+ ret = rtc_tm_to_time(alarm_tm, &alarm_secs);
+ if (ret)
+ goto err_unlock;
+
+ /* If alarm time is before current time, disable the alarm */
+ if (!alarm->enabled || alarm_secs <= rtc_secs) {
+ enable = 0;
+ } else {
+ /*
+ * Chip only support alarms up to one month in the future. Let's
+ * return an error if we get something after that limit.
+ * Comparison is done by incrementing rtc_tm month field by one
+ * and checking alarm value is still below.
+ */
+ if (rtc_tm.tm_mon == 11) { /* handle year wrapping */
+ rtc_tm.tm_mon = 0;
+ rtc_tm.tm_year += 1;
+ } else {
+ rtc_tm.tm_mon += 1;
+ }
+
+ ret = rtc_tm_to_time(&rtc_tm, &rtc_secs);
+ if (ret)
+ goto err_unlock;
+
+ if (alarm_secs > rtc_secs) {
+ dev_err(dev, "%s: max for alarm is one month (%d)\n",
+ __func__, ret);
+ ret = -EINVAL;
+ goto err_unlock;
+ }
+ }
+
+ /* Disable the alarm before modifying it */
+ ret = _isl12057_rtc_update_alarm(dev, 0);
+ if (ret < 0) {
+ dev_err(dev, "%s: unable to disable the alarm (%d)\n",
+ __func__, ret);
+ goto err_unlock;
+ }
+
+ /* Program alarm registers */
+ regs[0] = bin2bcd(alarm_tm->tm_sec) & 0x7f;
+ regs[1] = bin2bcd(alarm_tm->tm_min) & 0x7f;
+ regs[2] = bin2bcd(alarm_tm->tm_hour) & 0x3f;
+ regs[3] = bin2bcd(alarm_tm->tm_mday) & 0x3f;
+
+ ret = regmap_bulk_write(data->regmap, ISL12057_REG_A1_SC, regs,
+ ISL12057_A1_SEC_LEN);
+ if (ret < 0) {
+ dev_err(dev, "%s: writing alarm section failed (%d)\n",
+ __func__, ret);
+ goto err_unlock;
+ }
+
+ /* Enable or disable alarm */
+ ret = _isl12057_rtc_update_alarm(dev, enable);
+
+err_unlock:
+ mutex_unlock(&data->lock);
+
+ return ret;
+}
+
static int isl12057_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
struct isl12057_rtc_data *data = dev_get_drvdata(dev);
@@ -262,12 +457,85 @@ static int isl12057_check_rtc_status(struct device *dev, struct regmap *regmap)
return 0;
}
+#ifdef CONFIG_OF
+/*
+ * One would expect the device to be marked as a wakeup source only
+ * when an IRQ pin of the RTC is routed to an interrupt line of the
+ * CPU. In practice, such an IRQ pin can be connected to a PMIC and
+ * this allows the device to be powered up when RTC alarm rings. This
+ * is for instance the case on ReadyNAS 102, 104 and 2120. On those
+ * devices with no IRQ driectly connected to the SoC, the RTC chip
+ * can be forced as a wakeup source by stating that explicitly in
+ * the device's .dts file using the "isil,irq2-can-wakeup-machine"
+ * boolean property. This will guarantee 'wakealarm' sysfs entry is
+ * available on the device.
+ *
+ * The function below returns 1, i.e. the capability of the chip to
+ * wakeup the device, based on IRQ availability or if the boolean
+ * property has been set in the .dts file. Otherwise, it returns 0.
+ */
+
+static bool isl12057_can_wakeup_machine(struct device *dev)
+{
+ struct isl12057_rtc_data *data = dev_get_drvdata(dev);
+
+ return (data->irq || of_property_read_bool(dev->of_node,
+ "isil,irq2-can-wakeup-machine"));
+}
+#else
+static bool isl12057_can_wakeup_machine(struct device *dev)
+{
+ struct isl12057_rtc_data *data = dev_get_drvdata(dev);
+
+ return !!data->irq;
+}
+#endif
+
+static int isl12057_rtc_alarm_irq_enable(struct device *dev,
+ unsigned int enable)
+{
+ struct isl12057_rtc_data *rtc_data = dev_get_drvdata(dev);
+ int ret = -ENOTTY;
+
+ if (rtc_data->irq)
+ ret = isl12057_rtc_update_alarm(dev, enable);
+
+ return ret;
+}
+
+static irqreturn_t isl12057_rtc_interrupt(int irq, void *data)
+{
+ struct i2c_client *client = data;
+ struct isl12057_rtc_data *rtc_data = dev_get_drvdata(&client->dev);
+ struct rtc_device *rtc = rtc_data->rtc;
+ int ret, handled = IRQ_NONE;
+ unsigned int sr;
+
+ ret = regmap_read(rtc_data->regmap, ISL12057_REG_SR, &sr);
+ if (!ret && (sr & ISL12057_REG_SR_A1F)) {
+ dev_dbg(&client->dev, "RTC alarm!\n");
+
+ rtc_update_irq(rtc, 1, RTC_IRQF | RTC_AF);
+
+ /* Acknowledge and disable the alarm */
+ _isl12057_rtc_clear_alarm(&client->dev);
+ _isl12057_rtc_update_alarm(&client->dev, 0);
+
+ handled = IRQ_HANDLED;
+ }
+
+ return handled;
+}
+
static const struct rtc_class_ops rtc_ops = {
- .read_time = isl12057_rtc_read_time,
+ .read_time = _isl12057_rtc_read_time,
.set_time = isl12057_rtc_set_time,
+ .read_alarm = isl12057_rtc_read_alarm,
+ .set_alarm = isl12057_rtc_set_alarm,
+ .alarm_irq_enable = isl12057_rtc_alarm_irq_enable,
};
-static struct regmap_config isl12057_rtc_regmap_config = {
+static const struct regmap_config isl12057_rtc_regmap_config = {
.reg_bits = 8,
.val_bits = 8,
};
@@ -277,7 +545,6 @@ static int isl12057_probe(struct i2c_client *client,
{
struct device *dev = &client->dev;
struct isl12057_rtc_data *data;
- struct rtc_device *rtc;
struct regmap *regmap;
int ret;
@@ -310,13 +577,75 @@ static int isl12057_probe(struct i2c_client *client,
data->regmap = regmap;
dev_set_drvdata(dev, data);
- rtc = devm_rtc_device_register(dev, DRV_NAME, &rtc_ops, THIS_MODULE);
- return PTR_ERR_OR_ZERO(rtc);
+ if (client->irq > 0) {
+ ret = devm_request_threaded_irq(dev, client->irq, NULL,
+ isl12057_rtc_interrupt,
+ IRQF_SHARED|IRQF_ONESHOT,
+ DRV_NAME, client);
+ if (!ret)
+ data->irq = client->irq;
+ else
+ dev_err(dev, "%s: irq %d unavailable (%d)\n", __func__,
+ client->irq, ret);
+ }
+
+ if (isl12057_can_wakeup_machine(dev))
+ device_init_wakeup(dev, true);
+
+ data->rtc = devm_rtc_device_register(dev, DRV_NAME, &rtc_ops,
+ THIS_MODULE);
+ ret = PTR_ERR_OR_ZERO(data->rtc);
+ if (ret) {
+ dev_err(dev, "%s: unable to register RTC device (%d)\n",
+ __func__, ret);
+ goto err;
+ }
+
+ /* We cannot support UIE mode if we do not have an IRQ line */
+ if (!data->irq)
+ data->rtc->uie_unsupported = 1;
+
+err:
+ return ret;
+}
+
+static int isl12057_remove(struct i2c_client *client)
+{
+ if (isl12057_can_wakeup_machine(&client->dev))
+ device_init_wakeup(&client->dev, false);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int isl12057_rtc_suspend(struct device *dev)
+{
+ struct isl12057_rtc_data *rtc_data = dev_get_drvdata(dev);
+
+ if (rtc_data->irq && device_may_wakeup(dev))
+ return enable_irq_wake(rtc_data->irq);
+
+ return 0;
+}
+
+static int isl12057_rtc_resume(struct device *dev)
+{
+ struct isl12057_rtc_data *rtc_data = dev_get_drvdata(dev);
+
+ if (rtc_data->irq && device_may_wakeup(dev))
+ return disable_irq_wake(rtc_data->irq);
+
+ return 0;
}
+#endif
+
+static SIMPLE_DEV_PM_OPS(isl12057_rtc_pm_ops, isl12057_rtc_suspend,
+ isl12057_rtc_resume);
#ifdef CONFIG_OF
static const struct of_device_id isl12057_dt_match[] = {
- { .compatible = "isl,isl12057" },
+ { .compatible = "isl,isl12057" }, /* for backward compat., don't use */
+ { .compatible = "isil,isl12057" },
{ },
};
#endif
@@ -331,9 +660,11 @@ static struct i2c_driver isl12057_driver = {
.driver = {
.name = DRV_NAME,
.owner = THIS_MODULE,
+ .pm = &isl12057_rtc_pm_ops,
.of_match_table = of_match_ptr(isl12057_dt_match),
},
.probe = isl12057_probe,
+ .remove = isl12057_remove,
.id_table = isl12057_id,
};
module_i2c_driver(isl12057_driver);