From 869dfc875e32fd832385fd52ce54525a10401ed6 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Tue, 5 Jan 2010 12:48:08 +0100 Subject: [PATCH] driver core: Add class_attr_string for simple read-only string Several drivers just export a static string as class attributes. Use the new extensible attribute support to define a simple CLASS_ATTR_STRING() macro for this. This will allow to remove code from drivers in followon patches. Signed-off-by: Andi Kleen Signed-off-by: Greg Kroah-Hartman --- drivers/base/class.c | 10 ++++++++++ include/linux/device.h | 17 +++++++++++++++++ 2 files changed, 27 insertions(+) diff --git a/drivers/base/class.c b/drivers/base/class.c index 34a2de9c5385..2e297cc4cd3d 100644 --- a/drivers/base/class.c +++ b/drivers/base/class.c @@ -490,6 +490,16 @@ void class_interface_unregister(struct class_interface *class_intf) class_put(parent); } +ssize_t show_class_attr_string(struct class *class, struct class_attribute *attr, + char *buf) +{ + struct class_attribute_string *cs; + cs = container_of(attr, struct class_attribute_string, attr); + return snprintf(buf, PAGE_SIZE, "%s\n", cs->str); +} + +EXPORT_SYMBOL_GPL(show_class_attr_string); + struct class_compat { struct kobject *kobj; }; diff --git a/include/linux/device.h b/include/linux/device.h index 190f8d30d1d3..f95d5bfe8248 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -265,6 +265,23 @@ extern int __must_check class_create_file(struct class *class, extern void class_remove_file(struct class *class, const struct class_attribute *attr); +/* Simple class attribute that is just a static string */ + +struct class_attribute_string { + struct class_attribute attr; + char *str; +}; + +/* Currently read-only only */ +#define _CLASS_ATTR_STRING(_name, _mode, _str) \ + { __ATTR(_name, _mode, show_class_attr_string, NULL), _str } +#define CLASS_ATTR_STRING(_name, _mode, _str) \ + struct class_attribute_string class_attr_##_name = \ + _CLASS_ATTR_STRING(_name, _mode, _str) + +extern ssize_t show_class_attr_string(struct class *class, struct class_attribute *attr, + char *buf); + struct class_interface { struct list_head node; struct class *class;