1 files changed, 305 insertions, 8 deletions

diff --git a/drivers/rtc/rtc-isl12057.c b/drivers/rtc/rtc-isl12057.c
index 6e1fcfb5d7e6..3ec73ad7f2d8 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);
@@ -262,9 +457,48 @@ static int isl12057_check_rtc_status(struct device *dev, struct regmap *regmap)
         return 0;
 }
 
+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 = {
@@ -277,7 +511,6 @@ 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;
 
@@ -310,10 +543,72 @@ 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);
+        }
+
+        device_init_wakeup(dev, !!data->irq);
+
+        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)
+{
+        struct isl12057_rtc_data *rtc_data = dev_get_drvdata(&client->dev);
+
+        if (rtc_data->irq)
+                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 (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 (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" },
@@ -331,9 +626,11 @@ 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);