sysfs: fix up device attribute read/write methods.

Remove @off and @count from the sysfs_ops, and the core attribute methods.

drivers/base/core.c

@@ -35,28 +35,26 @@ DECLARE_MUTEX(device_sem);
 extern struct attribute * dev_default_attrs[];
 
 static ssize_t
-dev_attr_show(struct kobject * kobj, struct attribute * attr,
-	      char * buf, size_t count, loff_t off)
+dev_attr_show(struct kobject * kobj, struct attribute * attr, char * buf)
 {
 	struct device_attribute * dev_attr = to_dev_attr(attr);
 	struct device * dev = to_dev(kobj);
 	ssize_t ret = 0;
 
 	if (dev_attr->show)
-		ret = dev_attr->show(dev,buf,count,off);
+		ret = dev_attr->show(dev,buf);
 	return ret;
 }
 
 static ssize_t
-dev_attr_store(struct kobject * kobj, struct attribute * attr,
-	       const char * buf, size_t count, loff_t off)
+dev_attr_store(struct kobject * kobj, struct attribute * attr, const char * buf)
 {
 	struct device_attribute * dev_attr = to_dev_attr(attr);
 	struct device * dev = to_dev(kobj);
 	ssize_t ret = 0;
 
 	if (dev_attr->store)
-		ret = dev_attr->store(dev,buf,count,off);
+		ret = dev_attr->store(dev,buf);
 	return ret;
 }
 

drivers/base/interface.c

@@ -10,21 +10,21 @@
 #include <linux/stat.h>
 #include <linux/string.h>
 
-static ssize_t device_read_name(struct device * dev, char * buf, size_t count, loff_t off)
+static ssize_t device_read_name(struct device * dev, char * buf)
 {
-	return off ? 0 : sprintf(buf,"%s\n",dev->name);
+	return sprintf(buf,"%s\n",dev->name);
 }
 
 static DEVICE_ATTR(name,S_IRUGO,device_read_name,NULL);
 
 static ssize_t
-device_read_power(struct device * dev, char * page, size_t count, loff_t off)
+device_read_power(struct device * dev, char * page)
 {
-	return off ? 0 : sprintf(page,"%d\n",dev->power_state);
+	return sprintf(page,"%d\n",dev->power_state);
 }
 
 static ssize_t
-device_write_power(struct device * dev, const char * buf, size_t count, loff_t off)
+device_write_power(struct device * dev, const char * buf)
 {
 	char	str_command[20];
 	char	str_level[20];
@@ -33,9 +33,6 @@ device_write_power(struct device * dev, const char * buf, size_t count, loff_t o
 	u32	int_level;
 	int	error = 0;
 
-	if (off)
-		return 0;
-
 	if (!dev->driver)
 		goto done;
 
@@ -83,7 +80,7 @@ device_write_power(struct device * dev, const char * buf, size_t count, loff_t o
 			error = 0;
 	}
  done:
-	return error < 0 ? error : count;
+	return error < 0 ? error : strlen(buf);
 }
 
 static DEVICE_ATTR(power,S_IWUSR | S_IRUGO,

include/linux/device.h

@@ -319,8 +319,8 @@ extern void device_release_driver(struct device * dev);
 
 struct device_attribute {
 	struct attribute	attr;
-	ssize_t (*show)(struct device * dev, char * buf, size_t count, loff_t off);
-	ssize_t (*store)(struct device * dev, const char * buf, size_t count, loff_t off);
+	ssize_t (*show)(struct device * dev, char * buf);
+	ssize_t (*store)(struct device * dev, const char * buf);
 };
 
 #define DEVICE_ATTR(_name,_mode,_show,_store) \