mei: add support for variable length mei headers.

Remove header size knowledge from me and txe hw layers,
this requires to change the write handler to accept
header and its length as well as data and its length.

HBM messages are fixed to use basic header, hence we add mei_hbm2slots()
that converts HBM message length and mei message header,
while mei_data2slots() converts data length directly to the slots.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 19 insertions, 6 deletions

diff --git a/drivers/misc/mei/mei_dev.h b/drivers/misc/mei/mei_dev.h
index e9f37085a628..06fb5fc67fe9 100644
--- a/drivers/misc/mei/mei_dev.h
+++ b/drivers/misc/mei/mei_dev.h
@@ -300,8 +300,8 @@ struct mei_hw_ops {
 	bool (*hbuf_is_ready)(struct mei_device *dev);
 	u32 (*hbuf_depth)(const struct mei_device *dev);
 	int (*write)(struct mei_device *dev,
-		     struct mei_msg_hdr *hdr,
-		     const unsigned char *buf);
+		     const void *hdr, size_t hdr_len,
+		     const void *data, size_t data_len);
 
 	int (*rdbuf_full_slots)(struct mei_device *dev);
 
@@ -528,8 +528,7 @@ static inline unsigned long mei_secs_to_jiffies(unsigned long sec)
 }
 
 /**
- * mei_data2slots - get slots - number of (dwords) from a message length
- *	+ size of the mei header
+ * mei_data2slots - get slots number from a message length
  *
  * @length: size of the messages in bytes
  *
@@ -537,6 +536,19 @@ static inline unsigned long mei_secs_to_jiffies(unsigned long sec)
  */
 static inline u32 mei_data2slots(size_t length)
 {
+	return DIV_ROUND_UP(length, MEI_SLOT_SIZE);
+}
+
+/**
+ * mei_hbm2slots - get slots number from a hbm message length
+ *                 length + size of the mei message header
+ *
+ * @length: size of the messages in bytes
+ *
+ * Return: number of slots
+ */
+static inline u32 mei_hbm2slots(size_t length)
+{
 	return DIV_ROUND_UP(sizeof(struct mei_msg_hdr) + length, MEI_SLOT_SIZE);
 }
 
@@ -656,9 +668,10 @@ static inline u32 mei_hbuf_depth(const struct mei_device *dev)
 }
 
 static inline int mei_write_message(struct mei_device *dev,
-				    struct mei_msg_hdr *hdr, const void *buf)
+				    const void *hdr, size_t hdr_len,
+				    const void *data, size_t data_len)
 {
-	return dev->ops->write(dev, hdr, buf);
+	return dev->ops->write(dev, hdr, hdr_len, data, data_len);
 }
 
 static inline u32 mei_read_hdr(const struct mei_device *dev)