net: dsa: mv88e6xxx: move generic VTU GetNext

Even though every switch model has a different way to access the VTU
Data bits, the base implementation of the VTU GetNext operation remains
the same: wait, write the first VID to iterate from, start the
operation, and read the next VID.

Move this generic implementation into global1_vtu.c and abstract the
handling of the start VID (similarly to the ATU GetNext implementation),
before introducing a new chip operation for specific chips.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 29 insertions, 0 deletions

diff --git a/drivers/net/dsa/mv88e6xxx/global1_vtu.c b/drivers/net/dsa/mv88e6xxx/global1_vtu.c
index 6ac3d0eeae6b..c3f55be873b3 100644
--- a/drivers/net/dsa/mv88e6xxx/global1_vtu.c
+++ b/drivers/net/dsa/mv88e6xxx/global1_vtu.c
@@ -113,6 +113,35 @@ int mv88e6xxx_g1_vtu_vid_write(struct mv88e6xxx_chip *chip,
 
 /* VLAN Translation Unit Operations */
 
+int mv88e6xxx_g1_vtu_getnext(struct mv88e6xxx_chip *chip,
+			     struct mv88e6xxx_vtu_entry *entry)
+{
+	int err;
+
+	err = mv88e6xxx_g1_vtu_op_wait(chip);
+	if (err)
+		return err;
+
+	/* To get the next higher active VID, the VTU GetNext operation can be
+	 * started again without setting the VID registers since it already
+	 * contains the last VID.
+	 *
+	 * To save a few hardware accesses and abstract this to the caller,
+	 * write the VID only once, when the entry is given as invalid.
+	 */
+	if (!entry->valid) {
+		err = mv88e6xxx_g1_vtu_vid_write(chip, entry);
+		if (err)
+			return err;
+	}
+
+	err = mv88e6xxx_g1_vtu_op(chip, GLOBAL_VTU_OP_VTU_GET_NEXT);
+	if (err)
+		return err;
+
+	return mv88e6xxx_g1_vtu_vid_read(chip, entry);
+}
+
 int mv88e6xxx_g1_vtu_flush(struct mv88e6xxx_chip *chip)
 {
 	int err;