Merge tag 'for-v4.6-rc/omap-fixes-a' of git://git.kernel.org/pub/scm/linux/kernel/git/pjw/omap-pending into omap-for-v4.6/fixes

ARM: OMAP2+: first hwmod fix for v4.6-rc

Fix a longstanding bug in the hwmod code that could cause
hardware SYSCONFIG register values to not match the kernel's
idea of what they should be, and that could result in lower
performance during IP block idle entry.

Basic build, boot, and PM test logs are available here:

http://www.pwsan.com/omap/testlogs/omap-hwmod-fixes-a-for-v4.6-rc/20160326231727/

1 files changed, 283 insertions, 193 deletions

diff --git a/drivers/rtc/rtc-ds3232.c b/drivers/rtc/rtc-ds3232.c
index 4e99ace66f74..7edc889729c5 100644
--- a/drivers/rtc/rtc-ds3232.c
+++ b/drivers/rtc/rtc-ds3232.c
@@ -1,19 +1,15 @@
 /*
- * RTC client/driver for the Maxim/Dallas DS3232 Real-Time Clock over I2C
+ * RTC client/driver for the Maxim/Dallas DS3232/DS3234 Real-Time Clock
  *
  * Copyright (C) 2009-2011 Freescale Semiconductor.
  * Author: Jack Lan <jack.lan@freescale.com>
+ * Copyright (C) 2008 MIMOMax Wireless Ltd.
  *
  * This program is free software; you can redistribute  it and/or modify it
  * under  the terms of  the GNU General  Public License as published by the
  * Free Software Foundation;  either version 2 of the  License, or (at your
  * option) any later version.
  */
-/*
- * It would be more efficient to use i2c msgs/i2c_transfer directly but, as
- * recommened in .../Documentation/i2c/writing-clients section
- * "Sending and receiving", using SMBus level communication is preferred.
- */
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
@@ -21,10 +17,11 @@
 #include <linux/module.h>
 #include <linux/interrupt.h>
 #include <linux/i2c.h>
+#include <linux/spi/spi.h>
 #include <linux/rtc.h>
 #include <linux/bcd.h>
-#include <linux/workqueue.h>
 #include <linux/slab.h>
+#include <linux/regmap.h>
 
 #define DS3232_REG_SECONDS	0x00
 #define DS3232_REG_MINUTES	0x01
@@ -50,39 +47,33 @@
 #       define DS3232_REG_SR_A1F   0x01
 
 struct ds3232 {
-	struct i2c_client *client;
+	struct device *dev;
+	struct regmap *regmap;
+	int irq;
 	struct rtc_device *rtc;
-	struct work_struct work;
 
-	/* The mutex protects alarm operations, and prevents a race
-	 * between the enable_irq() in the workqueue and the free_irq()
-	 * in the remove function.
-	 */
-	struct mutex mutex;
 	bool suspended;
-	int exiting;
 };
 
-static struct i2c_driver ds3232_driver;
-
-static int ds3232_check_rtc_status(struct i2c_client *client)
+static int ds3232_check_rtc_status(struct device *dev)
 {
+	struct ds3232 *ds3232 = dev_get_drvdata(dev);
 	int ret = 0;
 	int control, stat;
 
-	stat = i2c_smbus_read_byte_data(client, DS3232_REG_SR);
-	if (stat < 0)
-		return stat;
+	ret = regmap_read(ds3232->regmap, DS3232_REG_SR, &stat);
+	if (ret)
+		return ret;
 
 	if (stat & DS3232_REG_SR_OSF)
-		dev_warn(&client->dev,
+		dev_warn(dev,
 				"oscillator discontinuity flagged, "
 				"time unreliable\n");
 
 	stat &= ~(DS3232_REG_SR_OSF | DS3232_REG_SR_A1F | DS3232_REG_SR_A2F);
 
-	ret = i2c_smbus_write_byte_data(client, DS3232_REG_SR, stat);
-	if (ret < 0)
+	ret = regmap_write(ds3232->regmap, DS3232_REG_SR, stat);
+	if (ret)
 		return ret;
 
 	/* If the alarm is pending, clear it before requesting
@@ -90,31 +81,28 @@ static int ds3232_check_rtc_status(struct i2c_client *client)
 	 * before everything is initialized.
 	 */
 
-	control = i2c_smbus_read_byte_data(client, DS3232_REG_CR);
-	if (control < 0)
-		return control;
+	ret = regmap_read(ds3232->regmap, DS3232_REG_CR, &control);
+	if (ret)
+		return ret;
 
 	control &= ~(DS3232_REG_CR_A1IE | DS3232_REG_CR_A2IE);
 	control |= DS3232_REG_CR_INTCN;
 
-	return i2c_smbus_write_byte_data(client, DS3232_REG_CR, control);
+	return regmap_write(ds3232->regmap, DS3232_REG_CR, control);
 }
 
 static int ds3232_read_time(struct device *dev, struct rtc_time *time)
 {
-	struct i2c_client *client = to_i2c_client(dev);
+	struct ds3232 *ds3232 = dev_get_drvdata(dev);
 	int ret;
 	u8 buf[7];
 	unsigned int year, month, day, hour, minute, second;
 	unsigned int week, twelve_hr, am_pm;
 	unsigned int century, add_century = 0;
 
-	ret = i2c_smbus_read_i2c_block_data(client, DS3232_REG_SECONDS, 7, buf);
-
-	if (ret < 0)
+	ret = regmap_bulk_read(ds3232->regmap, DS3232_REG_SECONDS, buf, 7);
+	if (ret)
 		return ret;
-	if (ret < 7)
-		return -EIO;
 
 	second = buf[0];
 	minute = buf[1];
@@ -159,7 +147,7 @@ static int ds3232_read_time(struct device *dev, struct rtc_time *time)
 
 static int ds3232_set_time(struct device *dev, struct rtc_time *time)
 {
-	struct i2c_client *client = to_i2c_client(dev);
+	struct ds3232 *ds3232 = dev_get_drvdata(dev);
 	u8 buf[7];
 
 	/* Extract time from rtc_time and load into ds3232*/
@@ -179,8 +167,7 @@ static int ds3232_set_time(struct device *dev, struct rtc_time *time)
 		buf[6] = bin2bcd(time->tm_year);
 	}
 
-	return i2c_smbus_write_i2c_block_data(client,
-					      DS3232_REG_SECONDS, 7, buf);
+	return regmap_bulk_write(ds3232->regmap, DS3232_REG_SECONDS, buf, 7);
 }
 
 /*
@@ -190,24 +177,19 @@ static int ds3232_set_time(struct device *dev, struct rtc_time *time)
  */
 static int ds3232_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
 {
-	struct i2c_client *client = to_i2c_client(dev);
-	struct ds3232 *ds3232 = i2c_get_clientdata(client);
+	struct ds3232 *ds3232 = dev_get_drvdata(dev);
 	int control, stat;
 	int ret;
 	u8 buf[4];
 
-	mutex_lock(&ds3232->mutex);
-
-	ret = i2c_smbus_read_byte_data(client, DS3232_REG_SR);
-	if (ret < 0)
+	ret = regmap_read(ds3232->regmap, DS3232_REG_SR, &stat);
+	if (ret)
 		goto out;
-	stat = ret;
-	ret = i2c_smbus_read_byte_data(client, DS3232_REG_CR);
-	if (ret < 0)
+	ret = regmap_read(ds3232->regmap, DS3232_REG_CR, &control);
+	if (ret)
 		goto out;
-	control = ret;
-	ret = i2c_smbus_read_i2c_block_data(client, DS3232_REG_ALARM1, 4, buf);
-	if (ret < 0)
+	ret = regmap_bulk_read(ds3232->regmap, DS3232_REG_ALARM1, buf, 4);
+	if (ret)
 		goto out;
 
 	alarm->time.tm_sec = bcd2bin(buf[0] & 0x7F);
@@ -226,7 +208,6 @@ static int ds3232_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
 
 	ret = 0;
 out:
-	mutex_unlock(&ds3232->mutex);
 	return ret;
 }
 
@@ -236,166 +217,129 @@ out:
  */
 static int ds3232_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
 {
-	struct i2c_client *client = to_i2c_client(dev);
-	struct ds3232 *ds3232 = i2c_get_clientdata(client);
+	struct ds3232 *ds3232 = dev_get_drvdata(dev);
 	int control, stat;
 	int ret;
 	u8 buf[4];
 
-	if (client->irq <= 0)
+	if (ds3232->irq <= 0)
 		return -EINVAL;
 
-	mutex_lock(&ds3232->mutex);
-
 	buf[0] = bin2bcd(alarm->time.tm_sec);
 	buf[1] = bin2bcd(alarm->time.tm_min);
 	buf[2] = bin2bcd(alarm->time.tm_hour);
 	buf[3] = bin2bcd(alarm->time.tm_mday);
 
 	/* clear alarm interrupt enable bit */
-	ret = i2c_smbus_read_byte_data(client, DS3232_REG_CR);
-	if (ret < 0)
+	ret = regmap_read(ds3232->regmap, DS3232_REG_CR, &control);
+	if (ret)
 		goto out;
-	control = ret;
 	control &= ~(DS3232_REG_CR_A1IE | DS3232_REG_CR_A2IE);
-	ret = i2c_smbus_write_byte_data(client, DS3232_REG_CR, control);
-	if (ret < 0)
+	ret = regmap_write(ds3232->regmap, DS3232_REG_CR, control);
+	if (ret)
 		goto out;
 
 	/* clear any pending alarm flag */
-	ret = i2c_smbus_read_byte_data(client, DS3232_REG_SR);
-	if (ret < 0)
+	ret = regmap_read(ds3232->regmap, DS3232_REG_SR, &stat);
+	if (ret)
 		goto out;
-	stat = ret;
 	stat &= ~(DS3232_REG_SR_A1F | DS3232_REG_SR_A2F);
-	ret = i2c_smbus_write_byte_data(client, DS3232_REG_SR, stat);
-	if (ret < 0)
+	ret = regmap_write(ds3232->regmap, DS3232_REG_SR, stat);
+	if (ret)
 		goto out;
 
-	ret = i2c_smbus_write_i2c_block_data(client, DS3232_REG_ALARM1, 4, buf);
+	ret = regmap_bulk_write(ds3232->regmap, DS3232_REG_ALARM1, buf, 4);
+	if (ret)
+		goto out;
 
 	if (alarm->enabled) {
 		control |= DS3232_REG_CR_A1IE;
-		ret = i2c_smbus_write_byte_data(client, DS3232_REG_CR, control);
+		ret = regmap_write(ds3232->regmap, DS3232_REG_CR, control);
 	}
 out:
-	mutex_unlock(&ds3232->mutex);
 	return ret;
 }
 
-static void ds3232_update_alarm(struct i2c_client *client)
+static int ds3232_update_alarm(struct device *dev, unsigned int enabled)
 {
-	struct ds3232 *ds3232 = i2c_get_clientdata(client);
+	struct ds3232 *ds3232 = dev_get_drvdata(dev);
 	int control;
 	int ret;
-	u8 buf[4];
-
-	mutex_lock(&ds3232->mutex);
-
-	ret = i2c_smbus_read_i2c_block_data(client, DS3232_REG_ALARM1, 4, buf);
-	if (ret < 0)
-		goto unlock;
-
-	buf[0] = bcd2bin(buf[0]) < 0 || (ds3232->rtc->irq_data & RTC_UF) ?
-								0x80 : buf[0];
-	buf[1] = bcd2bin(buf[1]) < 0 || (ds3232->rtc->irq_data & RTC_UF) ?
-								0x80 : buf[1];
-	buf[2] = bcd2bin(buf[2]) < 0 || (ds3232->rtc->irq_data & RTC_UF) ?
-								0x80 : buf[2];
-	buf[3] = bcd2bin(buf[3]) < 0 || (ds3232->rtc->irq_data & RTC_UF) ?
-								0x80 : buf[3];
-
-	ret = i2c_smbus_write_i2c_block_data(client, DS3232_REG_ALARM1, 4, buf);
-	if (ret < 0)
-		goto unlock;
 
-	control = i2c_smbus_read_byte_data(client, DS3232_REG_CR);
-	if (control < 0)
-		goto unlock;
+	ret = regmap_read(ds3232->regmap, DS3232_REG_CR, &control);
+	if (ret)
+		return ret;
 
-	if (ds3232->rtc->irq_data & (RTC_AF | RTC_UF))
+	if (enabled)
 		/* enable alarm1 interrupt */
 		control |= DS3232_REG_CR_A1IE;
 	else
 		/* disable alarm1 interrupt */
 		control &= ~(DS3232_REG_CR_A1IE);
-	i2c_smbus_write_byte_data(client, DS3232_REG_CR, control);
+	ret = regmap_write(ds3232->regmap, DS3232_REG_CR, control);
 
-unlock:
-	mutex_unlock(&ds3232->mutex);
+	return ret;
 }
 
 static int ds3232_alarm_irq_enable(struct device *dev, unsigned int enabled)
 {
-	struct i2c_client *client = to_i2c_client(dev);
-	struct ds3232 *ds3232 = i2c_get_clientdata(client);
+	struct ds3232 *ds3232 = dev_get_drvdata(dev);
 
-	if (client->irq <= 0)
+	if (ds3232->irq <= 0)
 		return -EINVAL;
 
-	if (enabled)
-		ds3232->rtc->irq_data |= RTC_AF;
-	else
-		ds3232->rtc->irq_data &= ~RTC_AF;
-
-	ds3232_update_alarm(client);
-	return 0;
+	return ds3232_update_alarm(dev, enabled);
 }
 
 static irqreturn_t ds3232_irq(int irq, void *dev_id)
 {
-	struct i2c_client *client = dev_id;
-	struct ds3232 *ds3232 = i2c_get_clientdata(client);
-
-	disable_irq_nosync(irq);
-
-	/*
-	 * If rtc as a wakeup source, can't schedule the work
-	 * at system resume flow, because at this time the i2c bus
-	 * has not been resumed.
-	 */
-	if (!ds3232->suspended)
-		schedule_work(&ds3232->work);
-
-	return IRQ_HANDLED;
-}
-
-static void ds3232_work(struct work_struct *work)
-{
-	struct ds3232 *ds3232 = container_of(work, struct ds3232, work);
-	struct i2c_client *client = ds3232->client;
+	struct device *dev = dev_id;
+	struct ds3232 *ds3232 = dev_get_drvdata(dev);
+	struct mutex *lock = &ds3232->rtc->ops_lock;
+	int ret;
 	int stat, control;
 
-	mutex_lock(&ds3232->mutex);
+	mutex_lock(lock);
 
-	stat = i2c_smbus_read_byte_data(client, DS3232_REG_SR);
-	if (stat < 0)
+	ret = regmap_read(ds3232->regmap, DS3232_REG_SR, &stat);
+	if (ret)
 		goto unlock;
 
 	if (stat & DS3232_REG_SR_A1F) {
-		control = i2c_smbus_read_byte_data(client, DS3232_REG_CR);
-		if (control < 0) {
-			pr_warn("Read Control Register error - Disable IRQ%d\n",
-				client->irq);
+		ret = regmap_read(ds3232->regmap, DS3232_REG_CR, &control);
+		if (ret) {
+			dev_warn(ds3232->dev,
+				 "Read Control Register error %d\n", ret);
 		} else {
 			/* disable alarm1 interrupt */
 			control &= ~(DS3232_REG_CR_A1IE);
-			i2c_smbus_write_byte_data(client, DS3232_REG_CR,
-						control);
+			ret = regmap_write(ds3232->regmap, DS3232_REG_CR,
+					   control);
+			if (ret) {
+				dev_warn(ds3232->dev,
+					 "Write Control Register error %d\n",
+					 ret);
+				goto unlock;
+			}
 
 			/* clear the alarm pend flag */
 			stat &= ~DS3232_REG_SR_A1F;
-			i2c_smbus_write_byte_data(client, DS3232_REG_SR, stat);
+			ret = regmap_write(ds3232->regmap, DS3232_REG_SR, stat);
+			if (ret) {
+				dev_warn(ds3232->dev,
+					 "Write Status Register error %d\n",
+					 ret);
+				goto unlock;
+			}
 
 			rtc_update_irq(ds3232->rtc, 1, RTC_AF | RTC_IRQF);
-
-			if (!ds3232->exiting)
-				enable_irq(client->irq);
 		}
 	}
 
 unlock:
-	mutex_unlock(&ds3232->mutex);
+	mutex_unlock(lock);
+
+	return IRQ_HANDLED;
 }
 
 static const struct rtc_class_ops ds3232_rtc_ops = {
@@ -406,67 +350,50 @@ static const struct rtc_class_ops ds3232_rtc_ops = {
 	.alarm_irq_enable = ds3232_alarm_irq_enable,
 };
 
-static int ds3232_probe(struct i2c_client *client,
-			const struct i2c_device_id *id)
+static int ds3232_probe(struct device *dev, struct regmap *regmap, int irq,
+			const char *name)
 {
 	struct ds3232 *ds3232;
 	int ret;
 
-	ds3232 = devm_kzalloc(&client->dev, sizeof(struct ds3232), GFP_KERNEL);
+	ds3232 = devm_kzalloc(dev, sizeof(*ds3232), GFP_KERNEL);
 	if (!ds3232)
 		return -ENOMEM;
 
-	ds3232->client = client;
-	i2c_set_clientdata(client, ds3232);
-
-	INIT_WORK(&ds3232->work, ds3232_work);
-	mutex_init(&ds3232->mutex);
+	ds3232->regmap = regmap;
+	ds3232->irq = irq;
+	ds3232->dev = dev;
+	dev_set_drvdata(dev, ds3232);
 
-	ret = ds3232_check_rtc_status(client);
+	ret = ds3232_check_rtc_status(dev);
 	if (ret)
 		return ret;
 
-	if (client->irq > 0) {
-		ret = devm_request_irq(&client->dev, client->irq, ds3232_irq,
-				       IRQF_SHARED, "ds3232", client);
+	if (ds3232->irq > 0) {
+		ret = devm_request_threaded_irq(dev, ds3232->irq, NULL,
+						ds3232_irq,
+						IRQF_SHARED | IRQF_ONESHOT,
+						name, dev);
 		if (ret) {
-			dev_err(&client->dev, "unable to request IRQ\n");
-		}
-		device_init_wakeup(&client->dev, 1);
-	}
-	ds3232->rtc = devm_rtc_device_register(&client->dev, client->name,
-					  &ds3232_rtc_ops, THIS_MODULE);
-	return PTR_ERR_OR_ZERO(ds3232->rtc);
-}
-
-static int ds3232_remove(struct i2c_client *client)
-{
-	struct ds3232 *ds3232 = i2c_get_clientdata(client);
-
-	if (client->irq > 0) {
-		mutex_lock(&ds3232->mutex);
-		ds3232->exiting = 1;
-		mutex_unlock(&ds3232->mutex);
-
-		devm_free_irq(&client->dev, client->irq, client);
-		cancel_work_sync(&ds3232->work);
+			ds3232->irq = 0;
+			dev_err(dev, "unable to request IRQ\n");
+		} else
+			device_init_wakeup(dev, 1);
 	}
+	ds3232->rtc = devm_rtc_device_register(dev, name, &ds3232_rtc_ops,
+						THIS_MODULE);
 
-	return 0;
+	return PTR_ERR_OR_ZERO(ds3232->rtc);
 }
 
 #ifdef CONFIG_PM_SLEEP
 static int ds3232_suspend(struct device *dev)
 {
 	struct ds3232 *ds3232 = dev_get_drvdata(dev);
-	struct i2c_client *client = to_i2c_client(dev);
 
-	if (device_can_wakeup(dev)) {
-		ds3232->suspended = true;
-		if (irq_set_irq_wake(client->irq, 1)) {
+	if (device_may_wakeup(dev)) {
+		if (enable_irq_wake(ds3232->irq))
 			dev_warn_once(dev, "Cannot set wakeup source\n");
-			ds3232->suspended = false;
-		}
 	}
 
 	return 0;
@@ -475,16 +402,9 @@ static int ds3232_suspend(struct device *dev)
 static int ds3232_resume(struct device *dev)
 {
 	struct ds3232 *ds3232 = dev_get_drvdata(dev);
-	struct i2c_client *client = to_i2c_client(dev);
 
-	if (ds3232->suspended) {
-		ds3232->suspended = false;
-
-		/* Clear the hardware alarm pend flag */
-		schedule_work(&ds3232->work);
-
-		irq_set_irq_wake(client->irq, 0);
-	}
+	if (device_may_wakeup(dev))
+		disable_irq_wake(ds3232->irq);
 
 	return 0;
 }
@@ -494,6 +414,27 @@ static const struct dev_pm_ops ds3232_pm_ops = {
 	SET_SYSTEM_SLEEP_PM_OPS(ds3232_suspend, ds3232_resume)
 };
 
+#if IS_ENABLED(CONFIG_I2C)
+
+static int ds3232_i2c_probe(struct i2c_client *client,
+			    const struct i2c_device_id *id)
+{
+	struct regmap *regmap;
+	static const struct regmap_config config = {
+		.reg_bits = 8,
+		.val_bits = 8,
+	};
+
+	regmap = devm_regmap_init_i2c(client, &config);
+	if (IS_ERR(regmap)) {
+		dev_err(&client->dev, "%s: regmap allocation failed: %ld\n",
+			__func__, PTR_ERR(regmap));
+		return PTR_ERR(regmap);
+	}
+
+	return ds3232_probe(&client->dev, regmap, client->irq, client->name);
+}
+
 static const struct i2c_device_id ds3232_id[] = {
 	{ "ds3232", 0 },
 	{ }
@@ -505,13 +446,162 @@ static struct i2c_driver ds3232_driver = {
 		.name = "rtc-ds3232",
 		.pm	= &ds3232_pm_ops,
 	},
-	.probe = ds3232_probe,
-	.remove = ds3232_remove,
+	.probe = ds3232_i2c_probe,
 	.id_table = ds3232_id,
 };
 
-module_i2c_driver(ds3232_driver);
+static int ds3232_register_driver(void)
+{
+	return i2c_add_driver(&ds3232_driver);
+}
+
+static void ds3232_unregister_driver(void)
+{
+	i2c_del_driver(&ds3232_driver);
+}
+
+#else
+
+static int ds3232_register_driver(void)
+{
+	return 0;
+}
+
+static void ds3232_unregister_driver(void)
+{
+}
+
+#endif
+
+#if IS_ENABLED(CONFIG_SPI_MASTER)
+
+static int ds3234_probe(struct spi_device *spi)
+{
+	int res;
+	unsigned int tmp;
+	static const struct regmap_config config = {
+		.reg_bits = 8,
+		.val_bits = 8,
+		.write_flag_mask = 0x80,
+	};
+	struct regmap *regmap;
+
+	regmap = devm_regmap_init_spi(spi, &config);
+	if (IS_ERR(regmap)) {
+		dev_err(&spi->dev, "%s: regmap allocation failed: %ld\n",
+			__func__, PTR_ERR(regmap));
+		return PTR_ERR(regmap);
+	}
+
+	spi->mode = SPI_MODE_3;
+	spi->bits_per_word = 8;
+	spi_setup(spi);
+
+	res = regmap_read(regmap, DS3232_REG_SECONDS, &tmp);
+	if (res)
+		return res;
+
+	/* Control settings
+	 *
+	 * CONTROL_REG
+	 * BIT 7	6	5	4	3	2	1	0
+	 *     EOSC	BBSQW	CONV	RS2	RS1	INTCN	A2IE	A1IE
+	 *
+	 *     0	0	0	1	1	1	0	0
+	 *
+	 * CONTROL_STAT_REG
+	 * BIT 7	6	5	4	3	2	1	0
+	 *     OSF	BB32kHz	CRATE1	CRATE0	EN32kHz	BSY	A2F	A1F
+	 *
+	 *     1	0	0	0	1	0	0	0
+	 */
+	res = regmap_read(regmap, DS3232_REG_CR, &tmp);
+	if (res)
+		return res;
+	res = regmap_write(regmap, DS3232_REG_CR, tmp & 0x1c);
+	if (res)
+		return res;
+
+	res = regmap_read(regmap, DS3232_REG_SR, &tmp);
+	if (res)
+		return res;
+	res = regmap_write(regmap, DS3232_REG_SR, tmp & 0x88);
+	if (res)
+		return res;
+
+	/* Print our settings */
+	res = regmap_read(regmap, DS3232_REG_CR, &tmp);
+	if (res)
+		return res;
+	dev_info(&spi->dev, "Control Reg: 0x%02x\n", tmp);
+
+	res = regmap_read(regmap, DS3232_REG_SR, &tmp);
+	if (res)
+		return res;
+	dev_info(&spi->dev, "Ctrl/Stat Reg: 0x%02x\n", tmp);
+
+	return ds3232_probe(&spi->dev, regmap, spi->irq, "ds3234");
+}
+
+static struct spi_driver ds3234_driver = {
+	.driver = {
+		.name	 = "ds3234",
+	},
+	.probe	 = ds3234_probe,
+};
+
+static int ds3234_register_driver(void)
+{
+	return spi_register_driver(&ds3234_driver);
+}
+
+static void ds3234_unregister_driver(void)
+{
+	spi_unregister_driver(&ds3234_driver);
+}
+
+#else
+
+static int ds3234_register_driver(void)
+{
+	return 0;
+}
+
+static void ds3234_unregister_driver(void)
+{
+}
+
+#endif
+
+static int __init ds323x_init(void)
+{
+	int ret;
+
+	ret = ds3232_register_driver();
+	if (ret) {
+		pr_err("Failed to register ds3232 driver: %d\n", ret);
+		return ret;
+	}
+
+	ret = ds3234_register_driver();
+	if (ret) {
+		pr_err("Failed to register ds3234 driver: %d\n", ret);
+		ds3232_unregister_driver();
+	}
+
+	return ret;
+}
+module_init(ds323x_init)
+
+static void __exit ds323x_exit(void)
+{
+	ds3234_unregister_driver();
+	ds3232_unregister_driver();
+}
+module_exit(ds323x_exit)
 
 MODULE_AUTHOR("Srikanth Srinivasan <srikanth.srinivasan@freescale.com>");
-MODULE_DESCRIPTION("Maxim/Dallas DS3232 RTC Driver");
+MODULE_AUTHOR("Dennis Aberilla <denzzzhome@yahoo.com>");
+MODULE_DESCRIPTION("Maxim/Dallas DS3232/DS3234 RTC Driver");
 MODULE_LICENSE("GPL");
+MODULE_ALIAS("spi:ds3234");