usb-net/pegasus: fix pegasus carrier detection
Broken by 4a1728a28a193aa388900714bbb1f375e08a6d8e which switched the
return semantics of read_mii_word() but didn't fix usage of
read_mii_word() to conform to the new semantics.
Setting carrier to off based on the NO_CARRIER flag is also incorrect as
that flag only triggers on TX failure and therefore isn't correct when
no frames are being transmitted. Since there is already a 2*HZ MII
carrier check going on, defer to that.
Add a TRUST_LINK_STATUS feature flag for adapters where the LINK_STATUS
flag is actually correct, and use that rather than the NO_CARRIER flag.
Signed-off-by: Dan Williams <dcbw@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/usb/net/pegasus.c b/drivers/usb/net/pegasus.c
index d48c024..6d12961 100644
--- a/drivers/usb/net/pegasus.c
+++ b/drivers/usb/net/pegasus.c
@@ -316,6 +316,7 @@
return ret;
}
+/* Returns 0 on success, error on failure */
static int read_mii_word(pegasus_t * pegasus, __u8 phy, __u8 indx, __u16 * regd)
{
int i;
@@ -847,10 +848,16 @@
* d[0].NO_CARRIER kicks in only with failed TX.
* ... so monitoring with MII may be safest.
*/
- if (d[0] & NO_CARRIER)
- netif_carrier_off(net);
- else
- netif_carrier_on(net);
+ if (pegasus->features & TRUST_LINK_STATUS) {
+ if (d[5] & LINK_STATUS)
+ netif_carrier_on(net);
+ else
+ netif_carrier_off(net);
+ } else {
+ /* Never set carrier _on_ based on ! NO_CARRIER */
+ if (d[0] & NO_CARRIER)
+ netif_carrier_off(net);
+ }
/* bytes 3-4 == rx_lostpkt, reg 2E/2F */
pegasus->stats.rx_missed_errors += ((d[3] & 0x7f) << 8) | d[4];
@@ -950,7 +957,7 @@
pegasus_t *pegasus = netdev_priv(net);
u16 tmp;
- if (!read_mii_word(pegasus, pegasus->phy, MII_BMSR, &tmp))
+ if (read_mii_word(pegasus, pegasus->phy, MII_BMSR, &tmp))
return;
if (tmp & BMSR_LSTATUS)