w1: add attribute groups to struct w1_family_ops

This lets w1 slave drivers declare an attribute group, and not have to
create/destroy sysfs files directly.  All w1 slave drivers will be fixed
to use this field up in follow-on patches to this one.

Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

2 files changed, 42 insertions, 32 deletions

diff --git a/drivers/w1/w1.c b/drivers/w1/w1.c
index 52b6c2f02f7a..22013ca2119c 100644
--- a/drivers/w1/w1.c
+++ b/drivers/w1/w1.c
@@ -124,9 +124,9 @@ ATTRIBUTE_GROUPS(w1_slave);
 
 /* Default family */
 
-static ssize_t w1_default_write(struct file *filp, struct kobject *kobj,
-                                struct bin_attribute *bin_attr,
-                                char *buf, loff_t off, size_t count)
+static ssize_t rw_write(struct file *filp, struct kobject *kobj,
+                        struct bin_attribute *bin_attr, char *buf, loff_t off,
+                        size_t count)
 {
         struct w1_slave *sl = kobj_to_w1_slave(kobj);
 
@@ -143,9 +143,9 @@ out_up:
         return count;
 }
 
-static ssize_t w1_default_read(struct file *filp, struct kobject *kobj,
-                               struct bin_attribute *bin_attr,
-                               char *buf, loff_t off, size_t count)
+static ssize_t rw_read(struct file *filp, struct kobject *kobj,
+                       struct bin_attribute *bin_attr, char *buf, loff_t off,
+                       size_t count)
 {
         struct w1_slave *sl = kobj_to_w1_slave(kobj);
 
@@ -155,29 +155,24 @@ static ssize_t w1_default_read(struct file *filp, struct kobject *kobj,
         return count;
 }
 
-static struct bin_attribute w1_default_attr = {
-      .attr = {
-              .name = "rw",
-              .mode = S_IRUGO | S_IWUSR,
-      },
-      .size = PAGE_SIZE,
-      .read = w1_default_read,
-      .write = w1_default_write,
+static BIN_ATTR_RW(rw, PAGE_SIZE);
+
+static struct bin_attribute *w1_slave_bin_attrs[] = {
+        &bin_attr_rw,
+        NULL,
 };
 
-static int w1_default_add_slave(struct w1_slave *sl)
-{
-        return sysfs_create_bin_file(&sl->dev.kobj, &w1_default_attr);
-}
+static const struct attribute_group w1_slave_default_group = {
+        .bin_attrs = w1_slave_bin_attrs,
+};
 
-static void w1_default_remove_slave(struct w1_slave *sl)
-{
-        sysfs_remove_bin_file(&sl->dev.kobj, &w1_default_attr);
-}
+static const struct attribute_group *w1_slave_default_groups[] = {
+        &w1_slave_default_group,
+        NULL,
+};
 
 static struct w1_family_ops w1_default_fops = {
-        .add_slave      = w1_default_add_slave,
-        .remove_slave   = w1_default_remove_slave,
+        .groups         = w1_slave_default_groups,
 };
 
 static struct w1_family w1_default_family = {
@@ -600,6 +595,7 @@ static int w1_bus_notify(struct notifier_block *nb, unsigned long action,
 {
         struct device *dev = data;
         struct w1_slave *sl;
+        struct w1_family_ops *fops;
         int err;
 
         /*
@@ -611,23 +607,36 @@ static int w1_bus_notify(struct notifier_block *nb, unsigned long action,
                 return 0;
 
         sl = dev_to_w1_slave(dev);
+        fops = sl->family->fops;
 
         switch (action) {
         case BUS_NOTIFY_ADD_DEVICE:
                 /* if the family driver needs to initialize something... */
-                if (sl->family->fops && sl->family->fops->add_slave &&
-                    ((err = sl->family->fops->add_slave(sl)) < 0)) {
-                        dev_err(&sl->dev,
-                                "sysfs file creation for [%s] failed. err=%d\n",
-                                dev_name(&sl->dev), err);
-                        return err;
+                if (fops->add_slave) {
+                        err = fops->add_slave(sl);
+                        if (err < 0) {
+                                dev_err(&sl->dev,
+                                        "add_slave() call failed. err=%d\n",
+                                        err);
+                                return err;
+                        }
+                }
+                if (fops->groups) {
+                        err = sysfs_create_groups(&sl->dev.kobj, fops->groups);
+                        if (err) {
+                                dev_err(&sl->dev,
+                                        "sysfs group creation failed. err=%d\n",
+                                        err);
+                                return err;
+                        }
                 }
 
                 break;
         case BUS_NOTIFY_DEL_DEVICE:
-                /* Remove our sysfs files */
-                if (sl->family->fops && sl->family->fops->remove_slave)
+                if (fops->remove_slave)
                         sl->family->fops->remove_slave(sl);
+                if (fops->groups)
+                        sysfs_remove_groups(&sl->dev.kobj, fops->groups);
                 break;
         }
         return 0;
diff --git a/drivers/w1/w1_family.h b/drivers/w1/w1_family.h
index 625dd08f775f..4ad0e81b6404 100644
--- a/drivers/w1/w1_family.h
+++ b/drivers/w1/w1_family.h
@@ -52,6 +52,7 @@ struct w1_family_ops
 {
         int  (* add_slave)(struct w1_slave *);
         void (* remove_slave)(struct w1_slave *);
+        const struct attribute_group **groups;
 };
 
 struct w1_family