usb-gadget/f_hid: use per-attribute show and store methods

To simplify the configfs interface and remove boilerplate code that also
causes binary bloat.

Signed-off-by: Christoph Hellwig <[e-mail]>
Reviewed-by: Andrzej Pietrasiewicz <[e-mail]>
Acked-by: Felipe Balbi <[e-mail]>
Signed-off-by: Nicholas Bellinger <[e-mail]>

drivers/usb/gadget/function/f_hid.c

···
 			    func_inst.group);
 }
 
-CONFIGFS_ATTR_STRUCT(f_hid_opts);
-CONFIGFS_ATTR_OPS(f_hid_opts);
-
 static void hid_attr_release(struct config_item *item)
 {
 	struct f_hid_opts *opts = to_f_hid_opts(item);
···
 
 static struct configfs_item_operations hidg_item_ops = {
 	.release	= hid_attr_release,
-	.show_attribute	= f_hid_opts_attr_show,
-	.store_attribute = f_hid_opts_attr_store,
 };
 
 #define F_HID_OPT(name, prec, limit)					\
-static ssize_t f_hid_opts_##name##_show(struct f_hid_opts *opts, char *page)\
+static ssize_t f_hid_opts_##name##_show(struct config_item *item, char *page)\
 {									\
+	struct f_hid_opts *opts = to_f_hid_opts(item);			\
 	int result;							\
 									\
 	mutex_lock(&opts->lock);					\
···
 	return result;							\
 }									\
 									\
-static ssize_t f_hid_opts_##name##_store(struct f_hid_opts *opts,	\
+static ssize_t f_hid_opts_##name##_store(struct config_item *item,	\
 					 const char *page, size_t len)	\
 {									\
+	struct f_hid_opts *opts = to_f_hid_opts(item);			\
 	int ret;							\
 	u##prec num;							\
 									\
···
 	return ret;							\
 }									\
 									\
-static struct f_hid_opts_attribute f_hid_opts_##name =			\
-	__CONFIGFS_ATTR(name, S_IRUGO | S_IWUSR, f_hid_opts_##name##_show,\
-			f_hid_opts_##name##_store)
+CONFIGFS_ATTR(f_hid_opts_, name)
 
 F_HID_OPT(subclass, 8, 255);
 F_HID_OPT(protocol, 8, 255);
 F_HID_OPT(report_length, 16, 65535);
 
-static ssize_t f_hid_opts_report_desc_show(struct f_hid_opts *opts, char *page)
+static ssize_t f_hid_opts_report_desc_show(struct config_item *item, char *page)
 {
+	struct f_hid_opts *opts = to_f_hid_opts(item);
 	int result;
 
 	mutex_lock(&opts->lock);
···
 	return result;
 }
 
-static ssize_t f_hid_opts_report_desc_store(struct f_hid_opts *opts,
+static ssize_t f_hid_opts_report_desc_store(struct config_item *item,
 					    const char *page, size_t len)
 {
+	struct f_hid_opts *opts = to_f_hid_opts(item);
 	int ret = -EBUSY;
 	char *d;
 
···
 	return ret;
 }
 
-static struct f_hid_opts_attribute f_hid_opts_report_desc =
-	__CONFIGFS_ATTR(report_desc, S_IRUGO | S_IWUSR,
-			f_hid_opts_report_desc_show,
-			f_hid_opts_report_desc_store);
+CONFIGFS_ATTR(f_hid_opts_, report_desc);
 
 static struct configfs_attribute *hid_attrs[] = {
-	&f_hid_opts_subclass.attr,
-	&f_hid_opts_protocol.attr,
-	&f_hid_opts_report_length.attr,
-	&f_hid_opts_report_desc.attr,
+	&f_hid_opts_attr_subclass,
+	&f_hid_opts_attr_protocol,
+	&f_hid_opts_attr_report_length,
+	&f_hid_opts_attr_report_desc,
 	NULL,
 };