sfc: cope with ENOSYS from efx_mcdi_get_workarounds()

GET_WORKAROUNDS was only introduced in May 2014, not all firmware
 will have it.  So call sites need to handle ENOSYS.
In this case we're probing the bug26807 workaround, which is not
 implemented in any firmware that doesn't have GET_WORKAROUNDS.
 So interpret ENOSYS as 'false'.

Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/sfc/ef10.c b/drivers/net/ethernet/sfc/ef10.c
index 119301769ddabdd09959622e5e02cee2d4bbda49..44071176859d1b99a248a99a005a47542ea68427 100644 (file)
--- a/drivers/net/ethernet/sfc/ef10.c
+++ b/drivers/net/ethernet/sfc/ef10.c
@@ -2277,20 +2277,27 @@ static int efx_ef10_ev_init(struct efx_channel *channel)
 
        /* Successfully created event queue on channel 0 */
        rc = efx_mcdi_get_workarounds(efx, &implemented, &enabled);
-       if (rc)
+       if (rc == -ENOSYS) {
+               /* GET_WORKAROUNDS was implemented before the bug26807
+                * workaround, thus the latter must be unavailable in this fw
+                */
+               nic_data->workaround_26807 = false;
+               rc = 0;
+       } else if (rc) {
                goto fail;
-
-       nic_data->workaround_26807 =
-               !!(enabled & MC_CMD_GET_WORKAROUNDS_OUT_BUG26807);
-
-       if (implemented & MC_CMD_GET_WORKAROUNDS_OUT_BUG26807 &&
-           !nic_data->workaround_26807) {
-               rc = efx_mcdi_set_workaround(efx, MC_CMD_WORKAROUND_BUG26807,
-                                            true);
-               if (!rc)
-                       nic_data->workaround_26807 = true;
-               else if (rc == -EPERM)
-                       rc = 0;
+       } else {
+               nic_data->workaround_26807 =
+                       !!(enabled & MC_CMD_GET_WORKAROUNDS_OUT_BUG26807);
+
+               if (implemented & MC_CMD_GET_WORKAROUNDS_OUT_BUG26807 &&
+                   !nic_data->workaround_26807) {
+                       rc = efx_mcdi_set_workaround(efx, MC_CMD_WORKAROUND_BUG26807,
+                                                    true);
+                       if (!rc)
+                               nic_data->workaround_26807 = true;
+                       else if (rc == -EPERM)
+                               rc = 0;
+               }
        }
 
        if (!rc)

diff --cc drivers/net/ethernet/sfc/mcdi.c
Simple merge