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path: root/target/linux/ixp4xx/patches-2.6.25/010-rtc_isl1208_new_style.patch
blob: a99bebc37d3da1c874de28175e2635be6d499d5f (plain)
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---
 drivers/rtc/rtc-isl1208.c |  357 +++++++++++++++++++++-------------------------
 1 file changed, 170 insertions(+), 187 deletions(-)

Index: linux-2.6.25-rc6-armeb/drivers/rtc/rtc-isl1208.c
===================================================================
--- linux-2.6.25-rc6-armeb.orig/drivers/rtc/rtc-isl1208.c	2008-03-20 10:26:41.000000000 +1030
+++ linux-2.6.25-rc6-armeb/drivers/rtc/rtc-isl1208.c	2008-03-20 10:26:53.000000000 +1030
@@ -15,16 +15,15 @@
 #include <linux/bcd.h>
 #include <linux/rtc.h>
 
-#define DRV_NAME "isl1208"
-#define DRV_VERSION "0.2"
+#define DRV_VERSION "0.3"
 
 /* Register map */
 /* rtc section */
 #define ISL1208_REG_SC  0x00
 #define ISL1208_REG_MN  0x01
 #define ISL1208_REG_HR  0x02
-#define ISL1208_REG_HR_MIL     (1<<7) /* 24h/12h mode */
-#define ISL1208_REG_HR_PM      (1<<5) /* PM/AM bit in 12h mode */
+#define ISL1208_REG_HR_MIL     (1<<7)	/* 24h/12h mode */
+#define ISL1208_REG_HR_PM      (1<<5)	/* PM/AM bit in 12h mode */
 #define ISL1208_REG_DT  0x03
 #define ISL1208_REG_MO  0x04
 #define ISL1208_REG_YR  0x05
@@ -33,14 +32,14 @@
 
 /* control/status section */
 #define ISL1208_REG_SR  0x07
-#define ISL1208_REG_SR_ARST    (1<<7) /* auto reset */
-#define ISL1208_REG_SR_XTOSCB  (1<<6) /* crystal oscillator */
-#define ISL1208_REG_SR_WRTC    (1<<4) /* write rtc */
-#define ISL1208_REG_SR_ALM     (1<<2) /* alarm */
-#define ISL1208_REG_SR_BAT     (1<<1) /* battery */
-#define ISL1208_REG_SR_RTCF    (1<<0) /* rtc fail */
+#define ISL1208_REG_SR_ARST    (1<<7)	/* auto reset */
+#define ISL1208_REG_SR_XTOSCB  (1<<6)	/* crystal oscillator */
+#define ISL1208_REG_SR_WRTC    (1<<4)	/* write rtc */
+#define ISL1208_REG_SR_ALM     (1<<2)	/* alarm */
+#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_09  0x09 /* reserved */
+#define ISL1208_REG_09  0x09	/* reserved */
 #define ISL1208_REG_ATR 0x0a
 #define ISL1208_REG_DTR 0x0b
 
@@ -58,39 +57,21 @@
 #define ISL1208_REG_USR2 0x13
 #define ISL1208_USR_SECTION_LEN 2
 
-/* i2c configuration */
-#define ISL1208_I2C_ADDR 0xde
-
-static const unsigned short normal_i2c[] = {
-	ISL1208_I2C_ADDR>>1, I2C_CLIENT_END
-};
-I2C_CLIENT_INSMOD; /* defines addr_data */
-
-static int isl1208_attach_adapter(struct i2c_adapter *adapter);
-static int isl1208_detach_client(struct i2c_client *client);
-
-static struct i2c_driver isl1208_driver = {
-	.driver		= {
-		.name	= DRV_NAME,
-	},
-	.id		= I2C_DRIVERID_ISL1208,
-	.attach_adapter = &isl1208_attach_adapter,
-	.detach_client	= &isl1208_detach_client,
-};
+static struct i2c_driver isl1208_driver;
 
 /* block read */
 static int
 isl1208_i2c_read_regs(struct i2c_client *client, u8 reg, u8 buf[],
-		       unsigned len)
+		      unsigned len)
 {
 	u8 reg_addr[1] = { reg };
 	struct i2c_msg msgs[2] = {
-		{ client->addr, client->flags, sizeof(reg_addr), reg_addr },
-		{ client->addr, client->flags | I2C_M_RD, len, buf }
+		{client->addr, client->flags, sizeof(reg_addr), reg_addr}
+		,
+		{client->addr, client->flags | I2C_M_RD, len, buf}
 	};
 	int ret;
 
-	BUG_ON(len == 0);
 	BUG_ON(reg > ISL1208_REG_USR2);
 	BUG_ON(reg + len > ISL1208_REG_USR2 + 1);
 
@@ -103,15 +84,14 @@
 /* block write */
 static int
 isl1208_i2c_set_regs(struct i2c_client *client, u8 reg, u8 const buf[],
-		       unsigned len)
+		     unsigned len)
 {
 	u8 i2c_buf[ISL1208_REG_USR2 + 2];
 	struct i2c_msg msgs[1] = {
-		{ client->addr, client->flags, len + 1, i2c_buf }
+		{client->addr, client->flags, len + 1, i2c_buf}
 	};
 	int ret;
 
-	BUG_ON(len == 0);
 	BUG_ON(reg > ISL1208_REG_USR2);
 	BUG_ON(reg + len > ISL1208_REG_USR2 + 1);
 
@@ -125,7 +105,8 @@
 }
 
 /* simple check to see wether we have a isl1208 */
-static int isl1208_i2c_validate_client(struct i2c_client *client)
+static int
+isl1208_i2c_validate_client(struct i2c_client *client)
 {
 	u8 regs[ISL1208_RTC_SECTION_LEN] = { 0, };
 	u8 zero_mask[ISL1208_RTC_SECTION_LEN] = {
@@ -139,24 +120,29 @@
 		return ret;
 
 	for (i = 0; i < ISL1208_RTC_SECTION_LEN; ++i) {
-		if (regs[i] & zero_mask[i]) /* check if bits are cleared */
+		if (regs[i] & zero_mask[i])	/* check if bits are cleared */
 			return -ENODEV;
 	}
 
 	return 0;
 }
 
-static int isl1208_i2c_get_sr(struct i2c_client *client)
+static int
+isl1208_i2c_get_sr(struct i2c_client *client)
 {
-	return i2c_smbus_read_byte_data(client, ISL1208_REG_SR) == -1 ? -EIO:0;
+	int sr = i2c_smbus_read_byte_data(client, ISL1208_REG_SR);
+	if (sr < 0)
+		return -EIO;
+
+	return sr;
 }
 
-static int isl1208_i2c_get_atr(struct i2c_client *client)
+static int
+isl1208_i2c_get_atr(struct i2c_client *client)
 {
 	int atr = i2c_smbus_read_byte_data(client, ISL1208_REG_ATR);
-
 	if (atr < 0)
-		return -EIO;
+		return atr;
 
 	/* The 6bit value in the ATR register controls the load
 	 * capacitance C_load * in steps of 0.25pF
@@ -169,51 +155,54 @@
 	 *
 	 */
 
-	atr &= 0x3f; /* mask out lsb */
-	atr ^= 1<<5; /* invert 6th bit */
-	atr += 2*9; /* add offset of 4.5pF; unit[atr] = 0.25pF */
+	atr &= 0x3f;		/* mask out lsb */
+	atr ^= 1 << 5;		/* invert 6th bit */
+	atr += 2 * 9;		/* add offset of 4.5pF; unit[atr] = 0.25pF */
 
 	return atr;
 }
 
-static int isl1208_i2c_get_dtr(struct i2c_client *client)
+static int
+isl1208_i2c_get_dtr(struct i2c_client *client)
 {
 	int dtr = i2c_smbus_read_byte_data(client, ISL1208_REG_DTR);
-
 	if (dtr < 0)
 		return -EIO;
 
 	/* dtr encodes adjustments of {-60,-40,-20,0,20,40,60} ppm */
-	dtr = ((dtr & 0x3) * 20) * (dtr & (1<<2) ? -1 : 1);
+	dtr = ((dtr & 0x3) * 20) * (dtr & (1 << 2) ? -1 : 1);
 
 	return dtr;
 }
 
-static int isl1208_i2c_get_usr(struct i2c_client *client)
+static int
+isl1208_i2c_get_usr(struct i2c_client *client)
 {
 	u8 buf[ISL1208_USR_SECTION_LEN] = { 0, };
 	int ret;
 
-	ret = isl1208_i2c_read_regs (client, ISL1208_REG_USR1, buf,
-				   ISL1208_USR_SECTION_LEN);
+	ret = isl1208_i2c_read_regs(client, ISL1208_REG_USR1, buf,
+				    ISL1208_USR_SECTION_LEN);
 	if (ret < 0)
 		return ret;
 
 	return (buf[1] << 8) | buf[0];
 }
 
-static int isl1208_i2c_set_usr(struct i2c_client *client, u16 usr)
+static int
+isl1208_i2c_set_usr(struct i2c_client *client, u16 usr)
 {
 	u8 buf[ISL1208_USR_SECTION_LEN];
 
 	buf[0] = usr & 0xff;
 	buf[1] = (usr >> 8) & 0xff;
 
-	return isl1208_i2c_set_regs (client, ISL1208_REG_USR1, buf,
-				     ISL1208_USR_SECTION_LEN);
+	return isl1208_i2c_set_regs(client, ISL1208_REG_USR1, buf,
+				    ISL1208_USR_SECTION_LEN);
 }
 
-static int isl1208_rtc_proc(struct device *dev, struct seq_file *seq)
+static int
+isl1208_rtc_proc(struct device *dev, struct seq_file *seq)
 {
 	struct i2c_client *const client = to_i2c_client(dev);
 	int sr, dtr, atr, usr;
@@ -230,20 +219,19 @@
 		   (sr & ISL1208_REG_SR_ALM) ? " ALM" : "",
 		   (sr & ISL1208_REG_SR_WRTC) ? " WRTC" : "",
 		   (sr & ISL1208_REG_SR_XTOSCB) ? " XTOSCB" : "",
-		   (sr & ISL1208_REG_SR_ARST) ? " ARST" : "",
-		   sr);
+		   (sr & ISL1208_REG_SR_ARST) ? " ARST" : "", sr);
 
 	seq_printf(seq, "batt_status\t: %s\n",
 		   (sr & ISL1208_REG_SR_RTCF) ? "bad" : "okay");
 
 	dtr = isl1208_i2c_get_dtr(client);
-	if (dtr >= 0 -1)
+	if (dtr >= 0 - 1)
 		seq_printf(seq, "digital_trim\t: %d ppm\n", dtr);
 
 	atr = isl1208_i2c_get_atr(client);
 	if (atr >= 0)
 		seq_printf(seq, "analog_trim\t: %d.%.2d pF\n",
-			   atr>>2, (atr&0x3)*25);
+			   atr >> 2, (atr & 0x3) * 25);
 
 	usr = isl1208_i2c_get_usr(client);
 	if (usr >= 0)
@@ -252,9 +240,8 @@
 	return 0;
 }
 
-
-static int isl1208_i2c_read_time(struct i2c_client *client,
-				 struct rtc_time *tm)
+static int
+isl1208_i2c_read_time(struct i2c_client *client, struct rtc_time *tm)
 {
 	int sr;
 	u8 regs[ISL1208_RTC_SECTION_LEN] = { 0, };
@@ -274,27 +261,30 @@
 
 	tm->tm_sec = BCD2BIN(regs[ISL1208_REG_SC]);
 	tm->tm_min = BCD2BIN(regs[ISL1208_REG_MN]);
-	{ /* HR field has a more complex interpretation */
+
+	/* HR field has a more complex interpretation */
+	{
 		const u8 _hr = regs[ISL1208_REG_HR];
-		if (_hr & ISL1208_REG_HR_MIL) /* 24h format */
+		if (_hr & ISL1208_REG_HR_MIL)	/* 24h format */
 			tm->tm_hour = BCD2BIN(_hr & 0x3f);
-		else { // 12h format
+		else {
+			/* 12h format */
 			tm->tm_hour = BCD2BIN(_hr & 0x1f);
-			if (_hr & ISL1208_REG_HR_PM) /* PM flag set */
+			if (_hr & ISL1208_REG_HR_PM)	/* PM flag set */
 				tm->tm_hour += 12;
 		}
 	}
 
 	tm->tm_mday = BCD2BIN(regs[ISL1208_REG_DT]);
-	tm->tm_mon = BCD2BIN(regs[ISL1208_REG_MO]) - 1; /* rtc starts at 1 */
+	tm->tm_mon = BCD2BIN(regs[ISL1208_REG_MO]) - 1;	/* rtc starts at 1 */
 	tm->tm_year = BCD2BIN(regs[ISL1208_REG_YR]) + 100;
 	tm->tm_wday = BCD2BIN(regs[ISL1208_REG_DW]);
 
 	return 0;
 }
 
-static int isl1208_i2c_read_alarm(struct i2c_client *client,
-				  struct rtc_wkalrm *alarm)
+static int
+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, };
@@ -307,7 +297,7 @@
 	}
 
 	sr = isl1208_i2c_read_regs(client, ISL1208_REG_SCA, regs,
-				  ISL1208_ALARM_SECTION_LEN);
+				   ISL1208_ALARM_SECTION_LEN);
 	if (sr < 0) {
 		dev_err(&client->dev, "%s: reading alarm section failed\n",
 			__func__);
@@ -315,23 +305,25 @@
 	}
 
 	/* MSB of each alarm register is an enable bit */
-	tm->tm_sec  = BCD2BIN(regs[ISL1208_REG_SCA-ISL1208_REG_SCA] & 0x7f);
-	tm->tm_min  = BCD2BIN(regs[ISL1208_REG_MNA-ISL1208_REG_SCA] & 0x7f);
-	tm->tm_hour = BCD2BIN(regs[ISL1208_REG_HRA-ISL1208_REG_SCA] & 0x3f);
-	tm->tm_mday = BCD2BIN(regs[ISL1208_REG_DTA-ISL1208_REG_SCA] & 0x3f);
-	tm->tm_mon  = BCD2BIN(regs[ISL1208_REG_MOA-ISL1208_REG_SCA] & 0x1f)-1;
-	tm->tm_wday = BCD2BIN(regs[ISL1208_REG_DWA-ISL1208_REG_SCA] & 0x03);
+	tm->tm_sec = BCD2BIN(regs[ISL1208_REG_SCA - ISL1208_REG_SCA] & 0x7f);
+	tm->tm_min = BCD2BIN(regs[ISL1208_REG_MNA - ISL1208_REG_SCA] & 0x7f);
+	tm->tm_hour = BCD2BIN(regs[ISL1208_REG_HRA - ISL1208_REG_SCA] & 0x3f);
+	tm->tm_mday = BCD2BIN(regs[ISL1208_REG_DTA - ISL1208_REG_SCA] & 0x3f);
+	tm->tm_mon =
+		BCD2BIN(regs[ISL1208_REG_MOA - ISL1208_REG_SCA] & 0x1f) - 1;
+	tm->tm_wday = BCD2BIN(regs[ISL1208_REG_DWA - ISL1208_REG_SCA] & 0x03);
 
 	return 0;
 }
 
-static int isl1208_rtc_read_time(struct device *dev, struct rtc_time *tm)
+static int
+isl1208_rtc_read_time(struct device *dev, struct rtc_time *tm)
 {
 	return isl1208_i2c_read_time(to_i2c_client(dev), tm);
 }
 
-static int isl1208_i2c_set_time(struct i2c_client *client,
-				struct rtc_time const *tm)
+static int
+isl1208_i2c_set_time(struct i2c_client *client, struct rtc_time const *tm)
 {
 	int sr;
 	u8 regs[ISL1208_RTC_SECTION_LEN] = { 0, };
@@ -353,7 +345,7 @@
 	}
 
 	/* set WRTC */
-	sr = i2c_smbus_write_byte_data (client, ISL1208_REG_SR,
+	sr = i2c_smbus_write_byte_data(client, ISL1208_REG_SR,
 				       sr | ISL1208_REG_SR_WRTC);
 	if (sr < 0) {
 		dev_err(&client->dev, "%s: writing SR failed\n", __func__);
@@ -369,7 +361,7 @@
 	}
 
 	/* clear WRTC again */
-	sr = i2c_smbus_write_byte_data (client, ISL1208_REG_SR,
+	sr = i2c_smbus_write_byte_data(client, ISL1208_REG_SR,
 				       sr & ~ISL1208_REG_SR_WRTC);
 	if (sr < 0) {
 		dev_err(&client->dev, "%s: writing SR failed\n", __func__);
@@ -380,70 +372,69 @@
 }
 
 
-static int isl1208_rtc_set_time(struct device *dev, struct rtc_time *tm)
+static int
+isl1208_rtc_set_time(struct device *dev, struct rtc_time *tm)
 {
 	return isl1208_i2c_set_time(to_i2c_client(dev), tm);
 }
 
-static int isl1208_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
+static int
+isl1208_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
 {
 	return isl1208_i2c_read_alarm(to_i2c_client(dev), alarm);
 }
 
 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,
+	.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, */
 };
 
 /* sysfs interface */
 
-static ssize_t isl1208_sysfs_show_atrim(struct device *dev,
-					struct device_attribute *attr,
-					char *buf)
+static ssize_t
+isl1208_sysfs_show_atrim(struct device *dev,
+			 struct device_attribute *attr, char *buf)
 {
-	int atr;
-
-	atr = isl1208_i2c_get_atr(to_i2c_client(dev));
+	int atr = isl1208_i2c_get_atr(to_i2c_client(dev));
 	if (atr < 0)
 		return atr;
 
-	return sprintf(buf, "%d.%.2d pF\n", atr>>2, (atr&0x3)*25);
+	return sprintf(buf, "%d.%.2d pF\n", atr >> 2, (atr & 0x3) * 25);
 }
+
 static DEVICE_ATTR(atrim, S_IRUGO, isl1208_sysfs_show_atrim, NULL);
 
-static ssize_t isl1208_sysfs_show_dtrim(struct device *dev,
-					struct device_attribute *attr,
-					char *buf)
+static ssize_t
+isl1208_sysfs_show_dtrim(struct device *dev,
+			 struct device_attribute *attr, char *buf)
 {
-	int dtr;
-
-	dtr = isl1208_i2c_get_dtr(to_i2c_client(dev));
+	int dtr = isl1208_i2c_get_dtr(to_i2c_client(dev));
 	if (dtr < 0)
 		return dtr;
 
 	return sprintf(buf, "%d ppm\n", dtr);
 }
+
 static DEVICE_ATTR(dtrim, S_IRUGO, isl1208_sysfs_show_dtrim, NULL);
 
-static ssize_t isl1208_sysfs_show_usr(struct device *dev,
-				       struct device_attribute *attr,
-				       char *buf)
+static ssize_t
+isl1208_sysfs_show_usr(struct device *dev,
+		       struct device_attribute *attr, char *buf)
 {
-	int usr;
-
-	usr = isl1208_i2c_get_usr(to_i2c_client(dev));
+	int usr = isl1208_i2c_get_usr(to_i2c_client(dev));
 	if (usr < 0)
 		return usr;
 
 	return sprintf(buf, "0x%.4x\n", usr);
 }
 
-static ssize_t isl1208_sysfs_store_usr(struct device *dev,
-				       struct device_attribute *attr,
-				       const char *buf, size_t count)
+static ssize_t
+isl1208_sysfs_store_usr(struct device *dev,
+			struct device_attribute *attr,
+			const char *buf, size_t count)
 {
 	int usr = -1;
 
@@ -460,124 +451,116 @@
 
 	return isl1208_i2c_set_usr(to_i2c_client(dev), usr) ? -EIO : count;
 }
+
 static DEVICE_ATTR(usr, S_IRUGO | S_IWUSR, isl1208_sysfs_show_usr,
 		   isl1208_sysfs_store_usr);
 
 static int
-isl1208_probe(struct i2c_adapter *adapter, int addr, int kind)
+isl1208_sysfs_register(struct device *dev)
 {
-	int rc = 0;
-	struct i2c_client *new_client = NULL;
-	struct rtc_device *rtc = NULL;
+	int err;
+
+	err = device_create_file(dev, &dev_attr_atrim);
+	if (err)
+		return err;
 
-	if (!i2c_check_functionality(adapter, I2C_FUNC_I2C)) {
-		rc = -ENODEV;
-		goto failout;
+	err = device_create_file(dev, &dev_attr_dtrim);
+	if (err) {
+		device_remove_file(dev, &dev_attr_atrim);
+		return err;
 	}
 
-	new_client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL);
-	if (new_client == NULL) {
-		rc = -ENOMEM;
-		goto failout;
+	err = device_create_file(dev, &dev_attr_usr);
+	if (err) {
+		device_remove_file(dev, &dev_attr_atrim);
+		device_remove_file(dev, &dev_attr_dtrim);
 	}
 
-	new_client->addr = addr;
-	new_client->adapter = adapter;
-	new_client->driver = &isl1208_driver;
-	new_client->flags = 0;
-	strcpy(new_client->name, DRV_NAME);
+	return 0;
+}
 
-	if (kind < 0) {
-		rc = isl1208_i2c_validate_client(new_client);
-		if (rc < 0)
-			goto failout;
-	}
+static int
+isl1208_sysfs_unregister(struct device *dev)
+{
+	device_remove_file(dev, &dev_attr_atrim);
+	device_remove_file(dev, &dev_attr_atrim);
+	device_remove_file(dev, &dev_attr_usr);
+
+	return 0;
+}
+
+static int
+isl1208_probe(struct i2c_client *client)
+{
+	int rc = 0;
+	struct rtc_device *rtc;
 
-	rc = i2c_attach_client(new_client);
-	if (rc < 0)
-		goto failout;
+	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
+		return -ENODEV;
 
-	dev_info(&new_client->dev,
+	if (isl1208_i2c_validate_client(client) < 0)
+		return -ENODEV;
+
+	dev_info(&client->dev,
 		 "chip found, driver version " DRV_VERSION "\n");
 
 	rtc = rtc_device_register(isl1208_driver.driver.name,
-				  &new_client->dev,
-				  &isl1208_rtc_ops, THIS_MODULE);
-
-	if (IS_ERR(rtc)) {
-		rc = PTR_ERR(rtc);
-		goto failout_detach;
-	}
+				  &client->dev, &isl1208_rtc_ops,
+				  THIS_MODULE);
+	if (IS_ERR(rtc))
+		return PTR_ERR(rtc);
 
-	i2c_set_clientdata(new_client, rtc);
+	i2c_set_clientdata(client, rtc);
 
-	rc = isl1208_i2c_get_sr(new_client);
+	rc = isl1208_i2c_get_sr(client);
 	if (rc < 0) {
-		dev_err(&new_client->dev, "reading status failed\n");
-		goto failout_unregister;
+		dev_err(&client->dev, "reading status failed\n");
+		goto exit_unregister;
 	}
 
 	if (rc & ISL1208_REG_SR_RTCF)
-		dev_warn(&new_client->dev, "rtc power failure detected, "
+		dev_warn(&client->dev, "rtc power failure detected, "
 			 "please set clock.\n");
 
-	rc = device_create_file(&new_client->dev, &dev_attr_atrim);
-	if (rc < 0)
-		goto failout_unregister;
-	rc = device_create_file(&new_client->dev, &dev_attr_dtrim);
-	if (rc < 0)
-		goto failout_atrim;
-	rc = device_create_file(&new_client->dev, &dev_attr_usr);
-	if (rc < 0)
-		goto failout_dtrim;
+	rc = isl1208_sysfs_register(&client->dev);
+	if (rc)
+		goto exit_unregister;
 
 	return 0;
 
- failout_dtrim:
-	device_remove_file(&new_client->dev, &dev_attr_dtrim);
- failout_atrim:
-	device_remove_file(&new_client->dev, &dev_attr_atrim);
- failout_unregister:
+      exit_unregister:
 	rtc_device_unregister(rtc);
- failout_detach:
-	i2c_detach_client(new_client);
- failout:
-	kfree(new_client);
-	return rc;
-}
 
-static int
-isl1208_attach_adapter (struct i2c_adapter *adapter)
-{
-	return i2c_probe(adapter, &addr_data, isl1208_probe);
+	return rc;
 }
 
 static int
-isl1208_detach_client(struct i2c_client *client)
+isl1208_remove(struct i2c_client *client)
 {
-	int rc;
-	struct rtc_device *const rtc = i2c_get_clientdata(client);
-
-	if (rtc)
-		rtc_device_unregister(rtc); /* do we need to kfree? */
-
-	rc = i2c_detach_client(client);
-	if (rc)
-		return rc;
+	struct rtc_device *rtc = i2c_get_clientdata(client);
 
-	kfree(client);
+	isl1208_sysfs_unregister(&client->dev);
+	rtc_device_unregister(rtc);
 
 	return 0;
 }
 
-/* module management */
+static struct i2c_driver isl1208_driver = {
+	.driver = {
+		   .name = "rtc-isl1208",
+		   },
+	.probe = isl1208_probe,
+	.remove = isl1208_remove,
+};
 
-static int __init isl1208_init(void)
+static int __init
+isl1208_init(void)
 {
 	return i2c_add_driver(&isl1208_driver);
 }
 
-static void __exit isl1208_exit(void)
+static void __exit
+isl1208_exit(void)
 {
 	i2c_del_driver(&isl1208_driver);
 }