Commit 8a914bac authored by Liam Beguin's avatar Liam Beguin Committed by Alexandre Belloni
Browse files

rtc: pcf2127: add alarm support 



Add alarm support for the pcf2127 RTC chip family.
Tested on pca2129.

Signed-off-by: default avatarLiam Beguin <lvb@xiphos.com>
Signed-off-by: default avatarAlexandre Belloni <alexandre.belloni@bootlin.com>
Reviewed-by: default avatarBruno Thomsen <bruno.thomsen@gmail.com>
Link: https://lore.kernel.org/r/20200630024211.12782-3-liambeguin@gmail.com
parent 985b30db

drivers/rtc/rtc-pcf2127.c

+134 −0
Original line number Diff line number Diff line
@@ -20,6 +20,7 @@ 
#include <linux/slab.h>

#include <linux/module.h>

#include <linux/of.h>

#include <linux/of_irq.h>

#include <linux/regmap.h>

#include <linux/watchdog.h>
@@ -28,7 +29,9 @@ 
#define PCF2127_BIT_CTRL1_TSF1			BIT(4)

/* Control register 2 */

#define PCF2127_REG_CTRL2		0x01

#define PCF2127_BIT_CTRL2_AIE			BIT(1)

#define PCF2127_BIT_CTRL2_TSIE			BIT(2)

#define PCF2127_BIT_CTRL2_AF			BIT(4)

#define PCF2127_BIT_CTRL2_TSF2			BIT(5)

/* Control register 3 */

#define PCF2127_REG_CTRL3		0x02
@@ -46,6 +49,12 @@ 
#define PCF2127_REG_DW			0x07

#define PCF2127_REG_MO			0x08

#define PCF2127_REG_YR			0x09

/* Alarm registers */

#define PCF2127_REG_ALARM_SC		0x0A

#define PCF2127_REG_ALARM_MN		0x0B

#define PCF2127_REG_ALARM_HR		0x0C

#define PCF2127_REG_ALARM_DM		0x0D

#define PCF2127_REG_ALARM_DW		0x0E

/* Watchdog registers */

#define PCF2127_REG_WD_CTL		0x10

#define PCF2127_BIT_WD_CTL_TF0			BIT(0)
@@ -324,6 +333,114 @@ static const struct watchdog_ops pcf2127_watchdog_ops = { 
	.set_timeout = pcf2127_wdt_set_timeout,

};



/* Alarm */

static int pcf2127_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)

{

	struct pcf2127 *pcf2127 = dev_get_drvdata(dev);

	unsigned int buf[5], ctrl2;

	int ret;



	ret = regmap_read(pcf2127->regmap, PCF2127_REG_CTRL2, &ctrl2);

	if (ret)

		return ret;



	ret = pcf2127_wdt_active_ping(&pcf2127->wdd);

	if (ret)

		return ret;



	ret = regmap_bulk_read(pcf2127->regmap, PCF2127_REG_ALARM_SC, buf,

			       sizeof(buf));

	if (ret)

		return ret;



	alrm->enabled = ctrl2 & PCF2127_BIT_CTRL2_AIE;

	alrm->pending = ctrl2 & PCF2127_BIT_CTRL2_AF;



	alrm->time.tm_sec = bcd2bin(buf[0] & 0x7F);

	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;

}



static int pcf2127_rtc_alarm_irq_enable(struct device *dev, u32 enable)

{

	struct pcf2127 *pcf2127 = dev_get_drvdata(dev);

	int ret;



	ret = regmap_update_bits(pcf2127->regmap, PCF2127_REG_CTRL2,

				 PCF2127_BIT_CTRL2_AIE,

				 enable ? PCF2127_BIT_CTRL2_AIE : 0);

	if (ret)

		return ret;



	return pcf2127_wdt_active_ping(&pcf2127->wdd);

}



static int pcf2127_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)

{

	struct pcf2127 *pcf2127 = dev_get_drvdata(dev);

	uint8_t buf[5];

	int ret;



	ret = regmap_update_bits(pcf2127->regmap, PCF2127_REG_CTRL2,

				 PCF2127_BIT_CTRL2_AF, 0);

	if (ret)

		return ret;



	ret = pcf2127_wdt_active_ping(&pcf2127->wdd);

	if (ret)

		return ret;



	buf[0] = bin2bcd(alrm->time.tm_sec);

	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);



	ret = regmap_bulk_write(pcf2127->regmap, PCF2127_REG_ALARM_SC, buf,

				sizeof(buf));

	if (ret)

		return ret;



	return pcf2127_rtc_alarm_irq_enable(dev, alrm->enabled);

}



static irqreturn_t pcf2127_rtc_irq(int irq, void *dev)

{

	struct pcf2127 *pcf2127 = dev_get_drvdata(dev);

	unsigned int ctrl2 = 0;

	int ret = 0;



	ret = regmap_read(pcf2127->regmap, PCF2127_REG_CTRL2, &ctrl2);

	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)

		return IRQ_NONE;



	return IRQ_HANDLED;

}



static const struct rtc_class_ops pcf2127_rtc_alrm_ops = {

	.ioctl            = pcf2127_rtc_ioctl,

	.read_time        = pcf2127_rtc_read_time,

	.set_time         = pcf2127_rtc_set_time,

	.read_alarm       = pcf2127_rtc_read_alarm,

	.set_alarm        = pcf2127_rtc_set_alarm,

	.alarm_irq_enable = pcf2127_rtc_alarm_irq_enable,

};



/* sysfs interface */



static ssize_t timestamp0_store(struct device *dev,
@@ -419,6 +536,7 @@ static int pcf2127_probe(struct device *dev, struct regmap *regmap, 
			const char *name, bool has_nvmem)

{

	struct pcf2127 *pcf2127;

	int alarm_irq = 0;

	u32 wdd_timeout;

	int ret = 0;
@@ -441,6 +559,22 @@ static int pcf2127_probe(struct device *dev, struct regmap *regmap, 
	pcf2127->rtc->range_max = RTC_TIMESTAMP_END_2099;

	pcf2127->rtc->set_start_time = true; /* Sets actual start to 1970 */



	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);

		if (ret) {

			dev_err(dev, "failed to request alarm irq\n");

			return ret;

		}

	}



	if (alarm_irq >= 0 || device_property_read_bool(dev, "wakeup-source")) {

		device_init_wakeup(dev, true);

		pcf2127->rtc->ops = &pcf2127_rtc_alrm_ops;

	}



	pcf2127->wdd.parent = dev;

	pcf2127->wdd.info = &pcf2127_wdt_info;

	pcf2127->wdd.ops = &pcf2127_watchdog_ops;

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