mei: add connect with vtag ioctl

This IOCTL is used to associate the current file descriptor
with a FW Client (given by UUID), and virtual tag (vtag).
The IOCTL opens a communication channel between a host client
and a FW client on a tagged channel. From this point on,
every reader  and write will communicate with the associated
FW client on the tagged channel. Upon close() the communication
is terminated.

The IOCTL argument is a struct with a union that contains
the input parameter and the output parameter for this IOCTL.

The input parameter is UUID of the FW Client, a vtag [0,255]
The output parameter is the properties of the FW client

Clients that do not support tagged connection
will respond with -EOPNOTSUPP

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Link: https://lore.kernel.org/r/20200818115147.2567012-12-tomas.winkler@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 49 insertions, 0 deletions

diff --git a/include/uapi/linux/mei.h b/include/uapi/linux/mei.h
index c6aec86cc5de..4f3638489d01 100644
--- a/include/uapi/linux/mei.h
+++ b/include/uapi/linux/mei.h
@@ -66,4 +66,53 @@ struct mei_connect_client_data {
  */
 #define IOCTL_MEI_NOTIFY_GET _IOR('H', 0x03, __u32)
 
+/**
+ * struct mei_connect_client_vtag - mei client information struct with vtag
+ *
+ * @in_client_uuid: UUID of client to connect
+ * @vtag: virtual tag
+ * @reserved: reserved for future use
+ */
+struct mei_connect_client_vtag {
+	uuid_le in_client_uuid;
+	__u8 vtag;
+	__u8 reserved[3];
+};
+
+/**
+ * struct mei_connect_client_data_vtag - IOCTL connect data union
+ *
+ * @connect: input connect data
+ * @out_client_properties: output client data
+ */
+struct mei_connect_client_data_vtag {
+	union {
+		struct mei_connect_client_vtag connect;
+		struct mei_client out_client_properties;
+	};
+};
+
+/**
+ * DOC:
+ * This IOCTL is used to associate the current file descriptor with a
+ * FW Client (given by UUID), and virtual tag (vtag).
+ * The IOCTL opens a communication channel between a host client and
+ * a FW client on a tagged channel. From this point on, every read
+ * and write will communicate with the associated FW client with
+ * on the tagged channel.
+ * Upone close() the communication is terminated.
+ *
+ * The IOCTL argument is a struct with a union that contains
+ * the input parameter and the output parameter for this IOCTL.
+ *
+ * The input parameter is UUID of the FW Client, a vtag [0,255]
+ * The output parameter is the properties of the FW client
+ * (FW protocool version and max message size).
+ *
+ * Clients that do not support tagged connection
+ * will respond with -EOPNOTSUPP.
+ */
+#define IOCTL_MEI_CONNECT_CLIENT_VTAG \
+	_IOWR('H', 0x04, struct mei_connect_client_data_vtag)
+
 #endif /* _LINUX_MEI_H  */