IB/hfi1: Check for QSFP presence before attempting reads

Attempting to read the status of a QSFP cable creates noise in the logs
and misses out on setting an appropriate Offline/Disabled Reason if the
cable is not plugged in. Check for this prior to attempting the read and
attendant retries.

Fixes: 673b975f1fba ("IB/hfi1: Add QSFP sanity pre-check")
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Easwar Hariharan <easwar.hariharan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

drivers/infiniband/hw/hfi1/chip.c

@@ -9533,8 +9533,11 @@ static int test_qsfp_read(struct hfi1_pportdata *ppd)
 	int ret;
 	u8 status;
 
-	/* report success if not a QSFP */
-	if (ppd->port_type != PORT_TYPE_QSFP)
+	/*
+	 * Report success if not a QSFP or, if it is a QSFP, but the cable is
+	 * not present
+	 */
+	if (ppd->port_type != PORT_TYPE_QSFP || !qsfp_mod_present(ppd))
 		return 0;
 
 	/* read byte 2, the status byte */