Commit cf044f0e authored by Ryan Mallon's avatar Ryan Mallon Committed by Linus Torvalds
Browse files

drivers/rtc/rtc-isl1208.c: add alarm support 



Add alarm/wakeup support to rtc isl1208 driver

Signed-off-by: default avatarRyan Mallon <ryan@bluewatersys.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent bc96ba74

drivers/rtc/rtc-isl1208.c

+171 −5
Original line number Diff line number Diff line
@@ -39,6 +39,8 @@ 
#define ISL1208_REG_SR_BAT     (1<<1)	/* battery */

#define ISL1208_REG_SR_RTCF    (1<<0)	/* rtc fail */

#define ISL1208_REG_INT 0x08

#define ISL1208_REG_INT_ALME   (1<<6)   /* alarm enable */

#define ISL1208_REG_INT_IM     (1<<7)   /* interrupt/alarm mode */

#define ISL1208_REG_09  0x09	/* reserved */

#define ISL1208_REG_ATR 0x0a

#define ISL1208_REG_DTR 0x0b
@@ -201,6 +203,30 @@ isl1208_i2c_set_usr(struct i2c_client *client, u16 usr) 
				    ISL1208_USR_SECTION_LEN);

}



static int

isl1208_rtc_toggle_alarm(struct i2c_client *client, int enable)

{

	int icr = i2c_smbus_read_byte_data(client, ISL1208_REG_INT);



	if (icr < 0) {

		dev_err(&client->dev, "%s: reading INT failed\n", __func__);

		return icr;

	}



	if (enable)

		icr |= ISL1208_REG_INT_ALME | ISL1208_REG_INT_IM;

	else

		icr &= ~(ISL1208_REG_INT_ALME | ISL1208_REG_INT_IM);



	icr = i2c_smbus_write_byte_data(client, ISL1208_REG_INT, icr);

	if (icr < 0) {

		dev_err(&client->dev, "%s: writing INT failed\n", __func__);

		return icr;

	}



	return 0;

}



static int

isl1208_rtc_proc(struct device *dev, struct seq_file *seq)

{
@@ -288,9 +314,8 @@ isl1208_i2c_read_alarm(struct i2c_client *client, struct rtc_wkalrm *alarm) 
{

	struct rtc_time *const tm = &alarm->time;

	u8 regs[ISL1208_ALARM_SECTION_LEN] = { 0, };

	int sr;

	int icr, yr, sr = isl1208_i2c_get_sr(client);



	sr = isl1208_i2c_get_sr(client);

	if (sr < 0) {

		dev_err(&client->dev, "%s: reading SR failed\n", __func__);

		return sr;
@@ -313,6 +338,73 @@ isl1208_i2c_read_alarm(struct i2c_client *client, struct rtc_wkalrm *alarm) 
		bcd2bin(regs[ISL1208_REG_MOA - ISL1208_REG_SCA] & 0x1f) - 1;

	tm->tm_wday = bcd2bin(regs[ISL1208_REG_DWA - ISL1208_REG_SCA] & 0x03);



	/* The alarm doesn't store the year so get it from the rtc section */

	yr = i2c_smbus_read_byte_data(client, ISL1208_REG_YR);

	if (yr < 0) {

		dev_err(&client->dev, "%s: reading RTC YR failed\n", __func__);

		return yr;

	}

	tm->tm_year = bcd2bin(yr) + 100;



	icr = i2c_smbus_read_byte_data(client, ISL1208_REG_INT);

	if (icr < 0) {

		dev_err(&client->dev, "%s: reading INT failed\n", __func__);

		return icr;

	}

	alarm->enabled = !!(icr & ISL1208_REG_INT_ALME);



	return 0;

}



static int

isl1208_i2c_set_alarm(struct i2c_client *client, struct rtc_wkalrm *alarm)

{

	struct rtc_time *alarm_tm = &alarm->time;

	u8 regs[ISL1208_ALARM_SECTION_LEN] = { 0, };

	const int offs = ISL1208_REG_SCA;

	unsigned long rtc_secs, alarm_secs;

	struct rtc_time rtc_tm;

	int err, enable;



	err = isl1208_i2c_read_time(client, &rtc_tm);

	if (err)

		return err;

	err = rtc_tm_to_time(&rtc_tm, &rtc_secs);

	if (err)

		return err;

	err = rtc_tm_to_time(alarm_tm, &alarm_secs);

	if (err)

		return err;



	/* If the alarm time is before the current time disable the alarm */

	if (!alarm->enabled || alarm_secs <= rtc_secs)

		enable = 0x00;

	else

		enable = 0x80;



	/* Program the alarm and enable it for each setting */

	regs[ISL1208_REG_SCA - offs] = bin2bcd(alarm_tm->tm_sec) | enable;

	regs[ISL1208_REG_MNA - offs] = bin2bcd(alarm_tm->tm_min) | enable;

	regs[ISL1208_REG_HRA - offs] = bin2bcd(alarm_tm->tm_hour) |

		ISL1208_REG_HR_MIL | enable;



	regs[ISL1208_REG_DTA - offs] = bin2bcd(alarm_tm->tm_mday) | enable;

	regs[ISL1208_REG_MOA - offs] = bin2bcd(alarm_tm->tm_mon + 1) | enable;

	regs[ISL1208_REG_DWA - offs] = bin2bcd(alarm_tm->tm_wday & 7) | enable;



	/* write ALARM registers */

	err = isl1208_i2c_set_regs(client, offs, regs,

				  ISL1208_ALARM_SECTION_LEN);

	if (err < 0) {

		dev_err(&client->dev, "%s: writing ALARM section failed\n",

			__func__);

		return err;

	}



	err = isl1208_rtc_toggle_alarm(client, enable);

	if (err)

		return err;



	return 0;

}
@@ -391,12 +483,63 @@ isl1208_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm) 
	return isl1208_i2c_read_alarm(to_i2c_client(dev), alarm);

}



static int

isl1208_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)

{

	return isl1208_i2c_set_alarm(to_i2c_client(dev), alarm);

}



static irqreturn_t

isl1208_rtc_interrupt(int irq, void *data)

{

	unsigned long timeout = jiffies + msecs_to_jiffies(1000);

	struct i2c_client *client = data;

	int handled = 0, sr, err;



	/*

	 * I2C reads get NAK'ed if we read straight away after an interrupt?

	 * Using a mdelay/msleep didn't seem to help either, so we work around

	 * this by continually trying to read the register for a short time.

	 */

	while (1) {

		sr = isl1208_i2c_get_sr(client);

		if (sr >= 0)

			break;



		if (time_after(jiffies, timeout)) {

			dev_err(&client->dev, "%s: reading SR failed\n",

				__func__);

			return sr;

		}

	}



	if (sr & ISL1208_REG_SR_ALM) {

		dev_dbg(&client->dev, "alarm!\n");



		/* Clear the alarm */

		sr &= ~ISL1208_REG_SR_ALM;

		sr = i2c_smbus_write_byte_data(client, ISL1208_REG_SR, sr);

		if (sr < 0)

			dev_err(&client->dev, "%s: writing SR failed\n",

				__func__);

		else

			handled = 1;



		/* Disable the alarm */

		err = isl1208_rtc_toggle_alarm(client, 0);

		if (err)

			return err;

	}



	return handled ? IRQ_HANDLED : IRQ_NONE;

}



static const struct rtc_class_ops isl1208_rtc_ops = {

	.proc = isl1208_rtc_proc,

	.read_time = isl1208_rtc_read_time,

	.set_time = isl1208_rtc_set_time,

	.read_alarm = isl1208_rtc_read_alarm,

	/*.set_alarm    = isl1208_rtc_set_alarm, */

	.set_alarm = isl1208_rtc_set_alarm,

};



/* sysfs interface */
@@ -488,11 +631,29 @@ isl1208_probe(struct i2c_client *client, const struct i2c_device_id *id) 
	dev_info(&client->dev,

		 "chip found, driver version " DRV_VERSION "\n");



	if (client->irq > 0) {

		rc = request_threaded_irq(client->irq, NULL,

					  isl1208_rtc_interrupt,

					  IRQF_SHARED,

					  isl1208_driver.driver.name, client);

		if (!rc) {

			device_init_wakeup(&client->dev, 1);

			enable_irq_wake(client->irq);

		} else {

			dev_err(&client->dev,

				"Unable to request irq %d, no alarm support\n",

				client->irq);

			client->irq = 0;

		}

	}



	rtc = rtc_device_register(isl1208_driver.driver.name,

				  &client->dev, &isl1208_rtc_ops,

				  THIS_MODULE);

	if (IS_ERR(rtc))

		return PTR_ERR(rtc);

	if (IS_ERR(rtc)) {

		rc = PTR_ERR(rtc);

		goto exit_free_irq;

	}



	i2c_set_clientdata(client, rtc);
@@ -514,6 +675,9 @@ isl1208_probe(struct i2c_client *client, const struct i2c_device_id *id) 


exit_unregister:

	rtc_device_unregister(rtc);

exit_free_irq:

	if (client->irq)

		free_irq(client->irq, client);



	return rc;

}
@@ -525,6 +689,8 @@ isl1208_remove(struct i2c_client *client) 


	sysfs_remove_group(&client->dev.kobj, &isl1208_rtc_sysfs_files);

	rtc_device_unregister(rtc);

	if (client->irq)

		free_irq(client->irq, client);



	return 0;

}