Commit e32e60a2 authored by Dylan Howey's avatar Dylan Howey Committed by Alexandre Belloni
Browse files

rtc: pcf2123: add alarm support 



Allows alarm to be controlled using, e.g., the RTC_WKALM_SET ioctl.

Signed-off-by: default avatarDylan Howey <Dylan.Howey@tennantco.com>
Signed-off-by: default avatarAlexandre Belloni <alexandre.belloni@bootlin.com>
parent c33850bb

drivers/rtc/rtc-pcf2123.c

+114 −2
Original line number Diff line number Diff line
@@ -242,6 +242,99 @@ static int pcf2123_rtc_set_time(struct device *dev, struct rtc_time *tm) 
	return 0;

}



static int pcf2123_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)

{

	struct pcf2123_plat_data *pdata = dev_get_platdata(dev);

	u8 rxbuf[4];

	int ret;

	unsigned int val = 0;



	ret = regmap_bulk_read(pdata->map, PCF2123_REG_ALRM_MN, rxbuf,

				sizeof(rxbuf));

	if (ret)

		return ret;



	alm->time.tm_min = bcd2bin(rxbuf[0] & 0x7F);

	alm->time.tm_hour = bcd2bin(rxbuf[1] & 0x3F);

	alm->time.tm_mday = bcd2bin(rxbuf[2] & 0x3F);

	alm->time.tm_wday = bcd2bin(rxbuf[3] & 0x07);



	dev_dbg(dev, "%s: alm is %ptR\n", __func__, &alm->time);



	ret = regmap_read(pdata->map, PCF2123_REG_CTRL2, &val);

	if (ret)

		return ret;



	alm->enabled = !!(val & CTRL2_AIE);



	return 0;

}



static int pcf2123_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)

{

	struct pcf2123_plat_data *pdata = dev_get_platdata(dev);

	u8 txbuf[4];

	int ret;



	dev_dbg(dev, "%s: alm is %ptR\n", __func__, &alm->time);



	/* Ensure alarm flag is clear */

	ret = regmap_update_bits(pdata->map, PCF2123_REG_CTRL2, CTRL2_AF, 0);

	if (ret)

		return ret;



	/* Disable alarm interrupt */

	ret = regmap_update_bits(pdata->map, PCF2123_REG_CTRL2, CTRL2_AIE, 0);

	if (ret)

		return ret;



	/* Set new alarm */

	txbuf[0] = bin2bcd(alm->time.tm_min & 0x7F);

	txbuf[1] = bin2bcd(alm->time.tm_hour & 0x3F);

	txbuf[2] = bin2bcd(alm->time.tm_mday & 0x3F);

	txbuf[3] = bin2bcd(alm->time.tm_wday & 0x07);



	ret = regmap_bulk_write(pdata->map, PCF2123_REG_ALRM_MN, txbuf,

				sizeof(txbuf));

	if (ret)

		return ret;



	/* Enable alarm interrupt */

	if (alm->enabled)	{

		ret = regmap_update_bits(pdata->map, PCF2123_REG_CTRL2,

						CTRL2_AIE, CTRL2_AIE);

		if (ret)

			return ret;

	}



	return 0;

}



static irqreturn_t pcf2123_rtc_irq(int irq, void *dev)

{

	struct pcf2123_plat_data *pdata = dev_get_platdata(dev);

	struct mutex *lock = &pdata->rtc->ops_lock;

	unsigned int val = 0;

	int ret = IRQ_NONE;



	mutex_lock(lock);

	regmap_read(pdata->map, PCF2123_REG_CTRL2, &val);



	/* Alarm? */

	if (val & CTRL2_AF) {

		ret = IRQ_HANDLED;



		/* Clear alarm flag */

		regmap_update_bits(pdata->map, PCF2123_REG_CTRL2, CTRL2_AF, 0);



		rtc_update_irq(pdata->rtc, 1, RTC_IRQF | RTC_AF);

	}



	mutex_unlock(lock);



	return ret;

}



static int pcf2123_reset(struct device *dev)

{

	struct pcf2123_plat_data *pdata = dev_get_platdata(dev);
@@ -281,7 +374,8 @@ static const struct rtc_class_ops pcf2123_rtc_ops = { 
	.set_time	= pcf2123_rtc_set_time,

	.read_offset	= pcf2123_read_offset,

	.set_offset	= pcf2123_set_offset,



	.read_alarm	= pcf2123_rtc_read_alarm,

	.set_alarm	= pcf2123_rtc_set_alarm,

};



static int pcf2123_probe(struct spi_device *spi)
@@ -289,7 +383,7 @@ static int pcf2123_probe(struct spi_device *spi) 
	struct rtc_device *rtc;

	struct rtc_time tm;

	struct pcf2123_plat_data *pdata;

	int ret;

	int ret = 0;



	pdata = devm_kzalloc(&spi->dev, sizeof(struct pcf2123_plat_data),

				GFP_KERNEL);
@@ -328,6 +422,24 @@ static int pcf2123_probe(struct spi_device *spi) 


	pdata->rtc = rtc;



	/* Register alarm irq */

	if (spi->irq > 0) {

		ret = devm_request_threaded_irq(&spi->dev, spi->irq, NULL,

				pcf2123_rtc_irq,

				IRQF_TRIGGER_LOW | IRQF_ONESHOT,

				pcf2123_driver.driver.name, &spi->dev);

		if (!ret)

			device_init_wakeup(&spi->dev, true);

		else

			dev_err(&spi->dev, "could not request irq.\n");

	}



	/* The PCF2123's alarm only has minute accuracy. Must add timer

	 * support to this driver to generate interrupts more than once

	 * per minute.

	 */

	pdata->rtc->uie_unsupported = 1;



	return 0;



kfree_exit: