rtc: pcf2127: fix alarm handling

Fix multiple issues when handling alarms:
 - Use threaded interrupt to avoid scheduling when atomic
 - Stop matching on week day as it may not be set correctly
 - Avoid parsing the DT interrupt and use what is provided by the i2c or
   spi subsystem
 - Avoid returning IRQ_NONE in case of error in the interrupt handler
 - Never write WDTF as specified in the datasheet
 - Set uie_unsupported, as for the pcf85063, setting alarms every seconds
   is not working correctly and confuses the RTC.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200812085114.474903-1-alexandre.belloni@bootlin.com
This commit is contained in:
Alexandre Belloni 2020-08-12 10:51:14 +02:00
parent 8a914bac44
commit 27006416be

View File

@ -33,6 +33,7 @@
#define PCF2127_BIT_CTRL2_TSIE BIT(2)
#define PCF2127_BIT_CTRL2_AF BIT(4)
#define PCF2127_BIT_CTRL2_TSF2 BIT(5)
#define PCF2127_BIT_CTRL2_WDTF BIT(6)
/* Control register 3 */
#define PCF2127_REG_CTRL3 0x02
#define PCF2127_BIT_CTRL3_BLIE BIT(0)
@ -55,6 +56,7 @@
#define PCF2127_REG_ALARM_HR 0x0C
#define PCF2127_REG_ALARM_DM 0x0D
#define PCF2127_REG_ALARM_DW 0x0E
#define PCF2127_BIT_ALARM_AE BIT(7)
/* Watchdog registers */
#define PCF2127_REG_WD_CTL 0x10
#define PCF2127_BIT_WD_CTL_TF0 BIT(0)
@ -360,7 +362,6 @@ static int pcf2127_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
alrm->time.tm_min = bcd2bin(buf[1] & 0x7F);
alrm->time.tm_hour = bcd2bin(buf[2] & 0x3F);
alrm->time.tm_mday = bcd2bin(buf[3] & 0x3F);
alrm->time.tm_wday = buf[4] & 0x07;
return 0;
}
@ -398,7 +399,7 @@ static int pcf2127_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
buf[1] = bin2bcd(alrm->time.tm_min);
buf[2] = bin2bcd(alrm->time.tm_hour);
buf[3] = bin2bcd(alrm->time.tm_mday);
buf[4] = (alrm->time.tm_wday & 0x07);
buf[4] = PCF2127_BIT_ALARM_AE; /* Do not match on week day */
ret = regmap_bulk_write(pcf2127->regmap, PCF2127_REG_ALARM_SC, buf,
sizeof(buf));
@ -418,17 +419,16 @@ static irqreturn_t pcf2127_rtc_irq(int irq, void *dev)
if (ret)
return IRQ_NONE;
if (ctrl2 & PCF2127_BIT_CTRL2_AF) {
regmap_write(pcf2127->regmap, PCF2127_REG_CTRL2,
ctrl2 & ~PCF2127_BIT_CTRL2_AF);
rtc_update_irq(pcf2127->rtc, 1, RTC_IRQF | RTC_AF);
}
ret = pcf2127_wdt_active_ping(&pcf2127->wdd);
if (ret)
if (!(ctrl2 & PCF2127_BIT_CTRL2_AF))
return IRQ_NONE;
regmap_write(pcf2127->regmap, PCF2127_REG_CTRL2,
ctrl2 & ~(PCF2127_BIT_CTRL2_AF | PCF2127_BIT_CTRL2_WDTF));
rtc_update_irq(pcf2127->rtc, 1, RTC_IRQF | RTC_AF);
pcf2127_wdt_active_ping(&pcf2127->wdd);
return IRQ_HANDLED;
}
@ -533,10 +533,9 @@ static const struct attribute_group pcf2127_attr_group = {
};
static int pcf2127_probe(struct device *dev, struct regmap *regmap,
const char *name, bool has_nvmem)
int alarm_irq, const char *name, bool has_nvmem)
{
struct pcf2127 *pcf2127;
int alarm_irq = 0;
u32 wdd_timeout;
int ret = 0;
@ -558,12 +557,13 @@ static int pcf2127_probe(struct device *dev, struct regmap *regmap,
pcf2127->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
pcf2127->rtc->range_max = RTC_TIMESTAMP_END_2099;
pcf2127->rtc->set_start_time = true; /* Sets actual start to 1970 */
pcf2127->rtc->uie_unsupported = 1;
alarm_irq = of_irq_get_byname(dev->of_node, "alarm");
if (alarm_irq >= 0) {
ret = devm_request_irq(dev, alarm_irq, pcf2127_rtc_irq,
IRQF_TRIGGER_LOW | IRQF_ONESHOT,
dev_name(dev), dev);
ret = devm_request_threaded_irq(dev, alarm_irq, NULL,
pcf2127_rtc_irq,
IRQF_TRIGGER_LOW | IRQF_ONESHOT,
dev_name(dev), dev);
if (ret) {
dev_err(dev, "failed to request alarm irq\n");
return ret;
@ -792,7 +792,7 @@ static int pcf2127_i2c_probe(struct i2c_client *client,
return PTR_ERR(regmap);
}
return pcf2127_probe(&client->dev, regmap,
return pcf2127_probe(&client->dev, regmap, client->irq,
pcf2127_i2c_driver.driver.name, id->driver_data);
}
@ -858,7 +858,8 @@ static int pcf2127_spi_probe(struct spi_device *spi)
return PTR_ERR(regmap);
}
return pcf2127_probe(&spi->dev, regmap, pcf2127_spi_driver.driver.name,
return pcf2127_probe(&spi->dev, regmap, spi->irq,
pcf2127_spi_driver.driver.name,
spi_get_device_id(spi)->driver_data);
}