diff options
Diffstat (limited to 'drivers/rtc')
-rw-r--r-- | drivers/rtc/rtc-m41t80.c | 180 |
1 files changed, 167 insertions, 13 deletions
diff --git a/drivers/rtc/rtc-m41t80.c b/drivers/rtc/rtc-m41t80.c index 1575b08..c724738 100644 --- a/drivers/rtc/rtc-m41t80.c +++ b/drivers/rtc/rtc-m41t80.c @@ -90,6 +90,46 @@ struct m41t80_data { struct rtc_device *rtc; }; +static irqreturn_t m41t80_handle_irq(int irq, void *dev_id) +{ + struct i2c_client *client = dev_id; + struct m41t80_data *m41t80 = i2c_get_clientdata(client); + struct mutex *lock = &m41t80->rtc->ops_lock; + unsigned long events = 0; + int flags, flags_afe; + + mutex_lock(lock); + + flags_afe = i2c_smbus_read_byte_data(client, M41T80_REG_ALARM_MON); + if (flags_afe < 0) { + mutex_unlock(lock); + return IRQ_NONE; + } + + flags = i2c_smbus_read_byte_data(client, M41T80_REG_FLAGS); + if (flags <= 0) { + mutex_unlock(lock); + return IRQ_NONE; + } + + if (flags & M41T80_FLAGS_AF) { + flags &= ~M41T80_FLAGS_AF; + flags_afe &= ~M41T80_ALMON_AFE; + events |= RTC_AF; + } + + if (events) { + rtc_update_irq(m41t80->rtc, 1, events); + i2c_smbus_write_byte_data(client, M41T80_REG_FLAGS, flags); + i2c_smbus_write_byte_data(client, M41T80_REG_ALARM_MON, + flags_afe); + } + + mutex_unlock(lock); + + return IRQ_HANDLED; +} + static int m41t80_get_datetime(struct i2c_client *client, struct rtc_time *tm) { @@ -167,10 +207,109 @@ static int m41t80_rtc_set_time(struct device *dev, struct rtc_time *tm) return m41t80_set_datetime(to_i2c_client(dev), tm); } -/* - * XXX - m41t80 alarm functionality is reported broken. - * until it is fixed, don't register alarm functions. - */ +static int m41t80_alarm_irq_enable(struct device *dev, unsigned int enabled) +{ + struct i2c_client *client = to_i2c_client(dev); + int flags, retval; + + flags = i2c_smbus_read_byte_data(client, M41T80_REG_ALARM_MON); + if (flags < 0) + return flags; + + if (enabled) + flags |= M41T80_ALMON_AFE; + else + flags &= ~M41T80_ALMON_AFE; + + retval = i2c_smbus_write_byte_data(client, M41T80_REG_ALARM_MON, flags); + if (retval < 0) { + dev_info(dev, "Unable to enable alarm IRQ %d\n", retval); + return retval; + } + return 0; +} + +static int m41t80_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + struct i2c_client *client = to_i2c_client(dev); + u8 alarmvals[5]; + int ret, err; + + alarmvals[0] = bin2bcd(alrm->time.tm_mon + 1); + alarmvals[1] = bin2bcd(alrm->time.tm_mday); + alarmvals[2] = bin2bcd(alrm->time.tm_hour); + alarmvals[3] = bin2bcd(alrm->time.tm_min); + alarmvals[4] = bin2bcd(alrm->time.tm_sec); + + /* Clear AF and AFE flags */ + ret = i2c_smbus_read_byte_data(client, M41T80_REG_ALARM_MON); + if (ret < 0) + return ret; + err = i2c_smbus_write_byte_data(client, M41T80_REG_ALARM_MON, + ret & ~(M41T80_ALMON_AFE)); + if (err < 0) { + dev_err(dev, "Unable to clear AFE bit\n"); + return err; + } + + ret = i2c_smbus_read_byte_data(client, M41T80_REG_FLAGS); + if (ret < 0) + return ret; + + err = i2c_smbus_write_byte_data(client, M41T80_REG_FLAGS, + ret & ~(M41T80_FLAGS_AF)); + if (err < 0) { + dev_err(dev, "Unable to clear AF bit\n"); + return err; + } + + /* Write the alarm */ + err = i2c_smbus_write_i2c_block_data(client, M41T80_REG_ALARM_MON, + 5, alarmvals); + if (err) + return err; + + /* Enable the alarm interrupt */ + if (alrm->enabled) { + alarmvals[0] |= M41T80_ALMON_AFE; + err = i2c_smbus_write_byte_data(client, M41T80_REG_ALARM_MON, + alarmvals[0]); + if (err) + return err; + } + + return 0; +} + +static int m41t80_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + struct i2c_client *client = to_i2c_client(dev); + u8 alarmvals[5]; + int flags, ret; + + ret = i2c_smbus_read_i2c_block_data(client, M41T80_REG_ALARM_MON, + 5, alarmvals); + if (ret != 5) + return ret < 0 ? ret : -EIO; + + flags = i2c_smbus_read_byte_data(client, M41T80_REG_FLAGS); + if (flags < 0) + return flags; + + alrm->time.tm_sec = bcd2bin(alarmvals[4] & 0x7f); + alrm->time.tm_min = bcd2bin(alarmvals[3] & 0x7f); + alrm->time.tm_hour = bcd2bin(alarmvals[2] & 0x3f); + alrm->time.tm_wday = -1; + alrm->time.tm_mday = bcd2bin(alarmvals[1] & 0x3f); + alrm->time.tm_mon = bcd2bin(alarmvals[0] & 0x3f); + alrm->time.tm_year = -1; + + alrm->enabled = !!(alarmvals[0] & M41T80_ALMON_AFE); + alrm->pending = (flags & M41T80_FLAGS_AF) && alrm->enabled; + + return 0; +} + static struct rtc_class_ops m41t80_rtc_ops = { .read_time = m41t80_rtc_read_time, .set_time = m41t80_rtc_set_time, @@ -591,7 +730,7 @@ static int m41t80_probe(struct i2c_client *client, int rc = 0; struct rtc_device *rtc = NULL; struct rtc_time tm; - struct m41t80_data *clientdata = NULL; + struct m41t80_data *m41t80_data = NULL; if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_I2C_BLOCK | I2C_FUNC_SMBUS_BYTE_DATA)) { @@ -599,26 +738,41 @@ static int m41t80_probe(struct i2c_client *client, return -ENODEV; } - clientdata = devm_kzalloc(&client->dev, sizeof(*clientdata), - GFP_KERNEL); - if (!clientdata) + m41t80_data = devm_kzalloc(&client->dev, sizeof(*m41t80_data), + GFP_KERNEL); + if (!m41t80_data) return -ENOMEM; - clientdata->features = id->driver_data; - i2c_set_clientdata(client, clientdata); + m41t80_data->features = id->driver_data; + i2c_set_clientdata(client, m41t80_data); + + if (client->irq > 0) { + rc = devm_request_threaded_irq(&client->dev, client->irq, + NULL, m41t80_handle_irq, + IRQF_TRIGGER_LOW | IRQF_ONESHOT, + "m41t80", client); + if (rc) { + dev_warn(&client->dev, "unable to request IRQ, alarms disabled\n"); + client->irq = 0; + } else { + m41t80_rtc_ops.read_alarm = m41t80_read_alarm; + m41t80_rtc_ops.set_alarm = m41t80_set_alarm; + m41t80_rtc_ops.alarm_irq_enable = m41t80_alarm_irq_enable; + } + } rtc = devm_rtc_device_register(&client->dev, client->name, &m41t80_rtc_ops, THIS_MODULE); if (IS_ERR(rtc)) return PTR_ERR(rtc); - clientdata->rtc = rtc; + m41t80_data->rtc = rtc; /* Make sure HT (Halt Update) bit is cleared */ rc = i2c_smbus_read_byte_data(client, M41T80_REG_ALARM_HOUR); if (rc >= 0 && rc & M41T80_ALHOUR_HT) { - if (clientdata->features & M41T80_FEATURE_HT) { + if (m41t80_data->features & M41T80_FEATURE_HT) { m41t80_get_datetime(client, &tm); dev_info(&client->dev, "HT bit was set!\n"); dev_info(&client->dev, @@ -664,7 +818,7 @@ static int m41t80_probe(struct i2c_client *client, } #ifdef CONFIG_RTC_DRV_M41T80_WDT - if (clientdata->features & M41T80_FEATURE_HT) { + if (m41t80_data->features & M41T80_FEATURE_HT) { save_client = client; rc = misc_register(&wdt_dev); if (rc) |