mei: bus: add name and uuid into device attributes

Export name and uuid via sysfs and uevent

Cc: [e-mail]
Signed-off-by: Tomas Winkler <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

Documentation/ABI/testing/sysfs-bus-mei

···
 		[e-mail]
 Description:	Stores the same MODALIAS value emitted by uevent
 		Format: mei:<mei device name>:<device uuid>:
+
+What:		/sys/bus/mei/devices/.../name
+Date:		May 2015
+KernelVersion:	4.2
+Contact:	Tomas Winkler <[e-mail]>
+Description:	Stores mei client device name
+		Format: string
+
+What:		/sys/bus/mei/devices/.../uuid
+Date:		May 2015
+KernelVersion:	4.2
+Contact:	Tomas Winkler <[e-mail]>
+Description:	Stores mei client device uuid
+		Format: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx

drivers/misc/mei/bus.c

···
 	return driver->remove(device);
 }
 
+static ssize_t name_show(struct device *dev, struct device_attribute *a,
+			     char *buf)
+{
+	struct mei_cl_device *device = to_mei_cl_device(dev);
+	size_t len;
+
+	len = snprintf(buf, PAGE_SIZE, "%s", device->name);
+
+	return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
+}
+static DEVICE_ATTR_RO(name);
+
+static ssize_t uuid_show(struct device *dev, struct device_attribute *a,
+			     char *buf)
+{
+	struct mei_cl_device *device = to_mei_cl_device(dev);
+	const uuid_le *uuid = mei_me_cl_uuid(device->me_cl);
+	size_t len;
+
+	len = snprintf(buf, PAGE_SIZE, "%pUl", uuid);
+
+	return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
+}
+static DEVICE_ATTR_RO(uuid);
+
 static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
 			     char *buf)
 {
···
 static DEVICE_ATTR_RO(modalias);
 
 static struct attribute *mei_cl_dev_attrs[] = {
+	&dev_attr_name.attr,
+	&dev_attr_uuid.attr,
 	&dev_attr_modalias.attr,
 	NULL,
 };
···
 {
 	struct mei_cl_device *device = to_mei_cl_device(dev);
 	const uuid_le *uuid = mei_me_cl_uuid(device->me_cl);
+
+	if (add_uevent_var(env, "MEI_CL_UUID=%pUl", uuid))
+		return -ENOMEM;
+
+	if (add_uevent_var(env, "MEI_CL_NAME=%s", device->name))
+		return -ENOMEM;
 
 	if (add_uevent_var(env, "MODALIAS=mei:%s:" MEI_CL_UUID_FMT ":",
 		device->name, MEI_CL_UUID_ARGS(uuid->b)))