[PATCH net-next v2 1/2] net: dsa: tag_yt921x: fix priority support

[David Yang <mmyangfl@gmail.com>]

The packet priority is embedded in 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