[PATCH net-next v4 1/4] net: dsa: tag_yt921x: fix priority support

[David Yang <mmyangfl@gmail.com>]

Packet priority is part of the rx tag. It defaults to 0, but adding DCB
support to the switch driver will break the tag driver by setting it to
non-zero.

Signed-off-by: David Yang <mmyangfl@gmail.com>
---
 net/dsa/tag_yt921x.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/net/dsa/tag_yt921x.c b/net/dsa/tag_yt921x.c
index 6bbfd42dc5df..b93715a057c7 100644
--- a/net/dsa/tag_yt921x.c
+++ b/net/dsa/tag_yt921x.c
@@ -17,7 +17,8 @@
  *   2: Rx Port
  *     15b: Rx Port Valid
  *     14b-11b: Rx Port
- *     10b-0b: Cmd?
+ *     10b-8b: Priority
+ *     7b-0b: Cmd
  *   2: Tx Port(s)
  *     15b: Tx Port(s) Valid
  *     10b-0b: Tx Port(s) Mask
@@ -33,7 +34,8 @@
 
 #define YT921X_TAG_PORT_EN		BIT(15)
 #define YT921X_TAG_RX_PORT_M		GENMASK(14, 11)
-#define YT921X_TAG_RX_CMD_M		GENMASK(10, 0)
+#define YT921X_TAG_RX_PRIO_M		GENMASK(10, 8)
+#define YT921X_TAG_RX_CMD_M		GENMASK(7, 0)
 #define  YT921X_TAG_RX_CMD(x)			FIELD_PREP(YT921X_TAG_RX_CMD_M, (x))
 #define  YT921X_TAG_RX_CMD_FORWARDED		0x80
 #define  YT921X_TAG_RX_CMD_UNK_UCAST		0xb2
@@ -98,6 +100,8 @@ yt921x_tag_rcv(struct sk_buff *skb, struct net_device *netdev)
 		return NULL;
 	}
 
+	skb->priority = FIELD_GET(YT921X_TAG_RX_PRIO_M, rx);
+
 	cmd = FIELD_GET(YT921X_TAG_RX_CMD_M, rx);
 	switch (cmd) {
 	case YT921X_TAG_RX_CMD_FORWARDED:
-- 
2.51.0