Currently each user of firmware_attributes_class has to manually set up
kobjects, devices, etc.
Provide a higher level API which takes care of the low-level details.
Signed-off-by: Thomas Weißschuh <linux@xxxxxxxxxxxxxx>
---
drivers/platform/x86/firmware_attributes_class.c | 146 +++++++++++++++++++++++
drivers/platform/x86/firmware_attributes_class.h | 37 ++++++
2 files changed, 183 insertions(+)
diff --git a/drivers/platform/x86/firmware_attributes_class.c b/drivers/platform/x86/firmware_attributes_class.c
index 736e96c186d9dc6d945517f090e9af903e93bbf4..70ceae5215820098b017bfda991a3c2a7824c98e 100644
--- a/drivers/platform/x86/firmware_attributes_class.c
+++ b/drivers/platform/x86/firmware_attributes_class.c
@@ -2,6 +2,9 @@
/* Firmware attributes class helper module */
+#include <linux/device/class.h>
+#include <linux/device.h>
+#include <linux/kobject.h>
#include <linux/module.h>
#include "firmware_attributes_class.h"
@@ -22,6 +25,149 @@ static __exit void fw_attributes_class_exit(void)
}
module_exit(fw_attributes_class_exit);
+static ssize_t fw_attributes_sysfs_show(struct kobject *kobj, struct attribute *attr, char *buf)
+{
+ struct firmware_attributes_device *fwadev = to_firmware_attribute_device(kobj);
+ const struct firmware_attribute *fw_attr = to_firmware_attribute(attr);
+
+ if (!fw_attr->show)
+ return -EIO;
+
+ return fw_attr->show(fwadev, fw_attr, buf);
+}
+
+static ssize_t fw_attributes_sysfs_store(struct kobject *kobj, struct attribute *attr,
+ const char *buf, size_t count)
+{
+ struct firmware_attributes_device *fwadev = to_firmware_attribute_device(kobj);
+ const struct firmware_attribute *fw_attr = to_firmware_attribute(attr);
+
+ if (!fw_attr->store)
+ return -EIO;
+
+ return fw_attr->store(fwadev, fw_attr, buf, count);
+}
+
+static const struct sysfs_ops fw_attributes_sysfs_ops = {
+ .show = fw_attributes_sysfs_show,
+ .store = fw_attributes_sysfs_store,
+};
+
+static void fw_attributes_attr_release(struct kobject *kobj)
+{
+ struct firmware_attributes_device *fwadev = to_firmware_attribute_device(kobj);
+ struct device *cdev;
+
+ cdev = fwadev->dev;
+
+ kfree(fwadev);
+ device_unregister(cdev);
+}
+
+static const struct kobj_type fw_attributes_attr_type = {
+ .sysfs_ops = &fw_attributes_sysfs_ops,
+ .release = fw_attributes_attr_release,
+};
+
+DEFINE_FREE(firmware_attributes_device_unregister, struct firmware_attributes_device *,
+ if (_T) firmware_attributes_device_unregister(_T))
+
+struct firmware_attributes_device *
+firmware_attributes_device_register(struct device *parent, const char *name,
+ const struct attribute_group **groups, void *data)
+{
+ struct firmware_attributes_device *fwadev = NULL;
+ struct device *cdev = NULL;
+ int ret;
+
+ fwadev = kzalloc(sizeof(*fwadev), GFP_KERNEL);
+ if (!fwadev)
+ return ERR_PTR(-ENOMEM);
+
+ cdev = device_create(&firmware_attributes_class, parent, MKDEV(0, 0), "%s", name);
+ if (IS_ERR(cdev))
+ return ERR_CAST(cdev);
+
+ fwadev->data = data;
+ fwadev->dev = cdev;
+
+ ret = kobject_init_and_add(&fwadev->attributes, &fw_attributes_attr_type, &cdev->kobj,
+ "attributes");
+ if (ret) {
+ device_del(cdev);
+ return ERR_PTR(ret);
+ }
+
+ if (groups) {
+ ret = sysfs_create_groups(&fwadev->attributes, groups);
+ if (ret) {
+ firmware_attributes_device_unregister(fwadev);
+ return ERR_PTR(ret);
+ }
+
+ kobject_uevent(&fwadev->dev->kobj, KOBJ_CHANGE);
+ }
+
+ return fwadev;
+}
+EXPORT_SYMBOL_GPL(firmware_attributes_device_register);
+
+void firmware_attributes_device_unregister(struct firmware_attributes_device *fwadev)
+{
+ kobject_del(&fwadev->attributes);
+ kobject_put(&fwadev->attributes);
+}
+EXPORT_SYMBOL_GPL(firmware_attributes_device_unregister);
+
+static void devm_firmware_attributes_device_release(void *data)
+{
+ struct firmware_attributes_device *fwadev = data;
+
+ firmware_attributes_device_unregister(fwadev);
+}
+
+struct firmware_attributes_device *
+devm_firmware_attributes_device_register(struct device *parent, const char *name,
+ const struct attribute_group **groups, void *data)
+{
+ struct firmware_attributes_device *fwadev;
+ int ret;
+
+ fwadev = firmware_attributes_device_register(parent, name, groups, data);
+ if (IS_ERR(fwadev))
+ return fwadev;
+
+ ret = devm_add_action_or_reset(parent, devm_firmware_attributes_device_release, fwadev);
+ if (ret)
+ return ERR_PTR(ret);
+
+ return fwadev;
+}
+EXPORT_SYMBOL_GPL(devm_firmware_attributes_device_register);
+
+static ssize_t firmware_attributes_type_show(struct firmware_attributes_device *fwadev,
+ const struct firmware_attribute *attr, char *buf)
+{
+ if (attr == &_firmware_attribute_type_string)
+ return sysfs_emit(buf, "string\n");
+ else if (attr == &_firmware_attribute_type_enumeration)
+ return sysfs_emit(buf, "enumeration\n");
+ else if (attr == &_firmware_attribute_type_integer)
+ return sysfs_emit(buf, "integer\n");
+ else
+ return -EIO;
+}
+
+#define __FW_TYPE_ATTR __ATTR(type, 0444, firmware_attributes_type_show, NULL)
+
+const struct firmware_attribute _firmware_attribute_type_string = __FW_TYPE_ATTR;
+EXPORT_SYMBOL_GPL(_firmware_attribute_type_string);
+const struct firmware_attribute _firmware_attribute_type_enumeration = __FW_TYPE_ATTR;
+EXPORT_SYMBOL_GPL(_firmware_attribute_type_enumeration);
+const struct firmware_attribute _firmware_attribute_type_integer = __FW_TYPE_ATTR;
+EXPORT_SYMBOL_GPL(_firmware_attribute_type_integer);
+
MODULE_AUTHOR("Mark Pearson <markpearson@xxxxxxxxxx>");
+MODULE_AUTHOR("Thomas Weißschuh <linux@xxxxxxxxxxxxxx>");
MODULE_DESCRIPTION("Firmware attributes class helper module");
MODULE_LICENSE("GPL");
diff --git a/drivers/platform/x86/firmware_attributes_class.h b/drivers/platform/x86/firmware_attributes_class.h
index d27abe54fcf9812a2f0868eec5426bbc8e7eb21c..66837ad9f65b8ca501dee73f48c01f2710d86bf5 100644
--- a/drivers/platform/x86/firmware_attributes_class.h
+++ b/drivers/platform/x86/firmware_attributes_class.h
@@ -5,8 +5,45 @@
#ifndef FW_ATTR_CLASS_H
#define FW_ATTR_CLASS_H
+#include <linux/device.h>
#include <linux/device/class.h>
+#include <linux/sysfs.h>
extern const struct class firmware_attributes_class;
+struct firmware_attributes_device {
+ struct device *dev;
+ struct kobject attributes;
+ void *data;
+};
+
+struct firmware_attribute {
+ struct attribute attr;
+ ssize_t (*show)(struct firmware_attributes_device *fwadev,
+ const struct firmware_attribute *attr, char *buf);
+ ssize_t (*store)(struct firmware_attributes_device *fwadev,
+ const struct firmware_attribute *attr, const char *buf, size_t count);
+};
+
+#define to_firmware_attribute(_a) container_of_const(_a, struct firmware_attribute, attr)
+#define to_firmware_attribute_device(_s) \
+ container_of_const(_s, struct firmware_attributes_device, attributes)
+
+extern const struct firmware_attribute _firmware_attribute_type_string;
+#define firmware_attribute_type_string ((struct attribute *)&_firmware_attribute_type_string.attr)
+extern const struct firmware_attribute _firmware_attribute_type_enumeration;
+#define firmware_attribute_type_enumeration ((struct attribute *)&_firmware_attribute_type_enumeration.attr)
+extern const struct firmware_attribute _firmware_attribute_type_integer;
+#define firmware_attribute_type_integer ((struct attribute *)&_firmware_attribute_type_integer.attr)
+
+struct firmware_attributes_device * __must_check
+firmware_attributes_device_register(struct device *parent, const char *name,
+ const struct attribute_group **groups, void *data);
+
+void firmware_attributes_device_unregister(struct firmware_attributes_device *fwadev);
+
+struct firmware_attributes_device * __must_check
+devm_firmware_attributes_device_register(struct device *parent, const char *name,
+ const struct attribute_group **groups, void *data);
+
#endif /* FW_ATTR_CLASS_H */
--
2.47.1
