[PATCH net-next 5/7] net: dsa: mv88e6xxx: fix VTU FID access for 6185

[Vivien Didelot]

The 6352 family has an entire register for its 12-bit FID used by the
VTU operations. The 6185 family has no such register. Its 8-bit FID
(called DBNum) is split in the VTU Operation register.

Modify the VTU read and write access to support this switch family.

Signed-off-by: Vivien Didelot <vivien.dide...@savoirfairelinux.com>
---
 drivers/net/dsa/mv88e6xxx.c | 20 +++++++++++++++++++-
 drivers/net/dsa/mv88e6xxx.h |  2 +-
 2 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/drivers/net/dsa/mv88e6xxx.c b/drivers/net/dsa/mv88e6xxx.c
index 4b3c466..366fda1 100644
--- a/drivers/net/dsa/mv88e6xxx.c
+++ b/drivers/net/dsa/mv88e6xxx.c
@@ -1355,6 +1355,17 @@ static int _mv88e6xxx_vtu_getnext(struct dsa_switch *ds,
                                return ret;
 
                        next.sid = ret & GLOBAL_VTU_SID_MASK;
+               } else if (mv88e6xxx_6185_family(ds)) {
+                       /* VTU DBNum[7:4] are located in VTU Operation 11:8, and
+                        * VTU DBNum[3:0] are located in VTU Operation 3:0
+                        */
+                       ret = _mv88e6xxx_reg_read(ds, REG_GLOBAL,
+                                                 GLOBAL_VTU_OP);
+                       if (ret < 0)
+                               return ret;
+
+                       next.fid = (ret & 0xf00) >> 4;
+                       next.fid |= ret & 0xf;
                }
        }
 
@@ -1416,6 +1427,7 @@ unlock:
 static int _mv88e6xxx_vtu_loadpurge(struct dsa_switch *ds,
                                    struct mv88e6xxx_vtu_stu_entry *entry)
 {
+       u16 op = GLOBAL_VTU_OP_VTU_LOAD_PURGE;
        u16 reg = 0;
        int ret;
 
@@ -1442,6 +1454,12 @@ static int _mv88e6xxx_vtu_loadpurge(struct dsa_switch 
*ds,
                ret = _mv88e6xxx_reg_write(ds, REG_GLOBAL, GLOBAL_VTU_FID, reg);
                if (ret < 0)
                        return ret;
+       } else if (mv88e6xxx_6185_family(ds)) {
+               /* VTU DBNum[7:4] are located in VTU Operation 11:8, and
+                * VTU DBNum[3:0] are located in VTU Operation 3:0
+                */
+               op |= (entry->fid & 0xf0) << 8;
+               op |= entry->fid & 0xf;
        }
 
        reg = GLOBAL_VTU_VID_VALID;
@@ -1451,7 +1469,7 @@ loadpurge:
        if (ret < 0)
                return ret;
 
-       return _mv88e6xxx_vtu_cmd(ds, GLOBAL_VTU_OP_VTU_LOAD_PURGE);
+       return _mv88e6xxx_vtu_cmd(ds, op);
 }
 
 static int _mv88e6xxx_stu_getnext(struct dsa_switch *ds, u8 sid,
diff --git a/drivers/net/dsa/mv88e6xxx.h b/drivers/net/dsa/mv88e6xxx.h
index 94d3cb3..b1f1269 100644
--- a/drivers/net/dsa/mv88e6xxx.h
+++ b/drivers/net/dsa/mv88e6xxx.h
@@ -376,7 +376,7 @@ struct mv88e6xxx_atu_entry {
 struct mv88e6xxx_vtu_stu_entry {
        /* VTU only */
        u16     vid;
-       u16     fid;
+       u16     fid; /* 8-bit DBNum in 88E6185 family */
 
        /* VTU and STU */
        u8      sid;
-- 
2.7.4