diff options
Diffstat (limited to 'drivers/rtc/rtc-ds1307.c')
| -rw-r--r-- | drivers/rtc/rtc-ds1307.c | 29 |
1 files changed, 27 insertions, 2 deletions
diff --git a/drivers/rtc/rtc-ds1307.c b/drivers/rtc/rtc-ds1307.c index cf685f67b391..bfedeb543bfd 100644 --- a/drivers/rtc/rtc-ds1307.c +++ b/drivers/rtc/rtc-ds1307.c @@ -851,6 +851,7 @@ static int ds1307_probe(struct i2c_client *client, struct chip_desc *chip = &chips[id->driver_data]; struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent); bool want_irq = false; + bool ds1307_can_wakeup_device = false; unsigned char *buf; struct ds1307_platform_data *pdata = dev_get_platdata(&client->dev); irq_handler_t irq_handler = ds1307_irq; @@ -898,6 +899,20 @@ static int ds1307_probe(struct i2c_client *client, ds1307->write_block_data = ds1307_write_block_data; } +#ifdef CONFIG_OF +/* + * For devices with no IRQ directly 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 "wakeup-source" boolean property. + * If the "wakeup-source" property is set, don't request an IRQ. + * This will guarantee the 'wakealarm' sysfs entry is available on the device, + * if supported by the RTC. + */ + if (of_property_read_bool(client->dev.of_node, "wakeup-source")) { + ds1307_can_wakeup_device = true; + } +#endif + switch (ds1307->type) { case ds_1337: case ds_1339: @@ -916,11 +931,13 @@ static int ds1307_probe(struct i2c_client *client, ds1307->regs[0] &= ~DS1337_BIT_nEOSC; /* - * Using IRQ? Disable the square wave and both alarms. + * Using IRQ or defined as wakeup-source? + * Disable the square wave and both alarms. * For some variants, be sure alarms can trigger when we're * running on Vbackup (BBSQI/BBSQW) */ - if (ds1307->client->irq > 0 && chip->alarm) { + if (chip->alarm && (ds1307->client->irq > 0 || + ds1307_can_wakeup_device)) { ds1307->regs[0] |= DS1337_BIT_INTCN | bbsqi_bitpos[ds1307->type]; ds1307->regs[0] &= ~(DS1337_BIT_A2IE | DS1337_BIT_A1IE); @@ -1135,6 +1152,14 @@ read_rtc: return PTR_ERR(ds1307->rtc); } + if (ds1307_can_wakeup_device) { + /* Disable request for an IRQ */ + want_irq = false; + dev_info(&client->dev, "'wakeup-source' is set, request for an IRQ is disabled!\n"); + /* We cannot support UIE mode if we do not have an IRQ line */ + ds1307->rtc->uie_unsupported = 1; + } + if (want_irq) { err = devm_request_threaded_irq(&client->dev, client->irq, NULL, irq_handler, |