ixgbe: extract PTP clock device from ptp_init

In order to properly handle a suspend/resume cycle, we cannot destroy
the PTP clock device. As part of this, we should only re-create the
device on first initialization. After a resume, when ixgbe_ptp_init is
called, we won't create a new clock, and we will use the old clock
device. To that end, this patch extracts the clock creation out of
ptp_init, and only calls it if we don't already have a ptp_clock
pointer.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_ptp.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_ptp.c
index 9d329f5..9df7e57 100644 (file)
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_ptp.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_ptp.c
@@ -851,16 +851,23 @@ void ixgbe_ptp_reset(struct ixgbe_adapter *adapter)
 }
 
 /**
- * ixgbe_ptp_init
+ * ixgbe_ptp_create_clock
  * @adapter: the ixgbe private adapter structure
  *
- * This function performs the required steps for enabling ptp
- * support. If ptp support has already been loaded it simply calls the
- * cyclecounter init routine and exits.
+ * This function performs setup of the user entry point function table and
+ * initializes the PTP clock device, which is used to access the clock-like
+ * features of the PTP core. It will be called by ixgbe_ptp_init, only if
+ * there isn't already a clock device (such as after a suspend/resume cycle,
+ * where the clock device wasn't destroyed).
  */
-void ixgbe_ptp_init(struct ixgbe_adapter *adapter)
+static int ixgbe_ptp_create_clock(struct ixgbe_adapter *adapter)
 {
        struct net_device *netdev = adapter->netdev;
+       long err;
+
+       /* do nothing if we already have a clock device */
+       if (!IS_ERR_OR_NULL(adapter->ptp_clock))
+               return 0;
 
        switch (adapter->hw.mac.type) {
        case ixgbe_mac_X540:
@@ -897,22 +904,53 @@ void ixgbe_ptp_init(struct ixgbe_adapter *adapter)
                break;
        default:
                adapter->ptp_clock = NULL;
-               return;
+               return -EOPNOTSUPP;
        }
 
-       spin_lock_init(&adapter->tmreg_lock);
-       INIT_WORK(&adapter->ptp_tx_work, ixgbe_ptp_tx_hwtstamp_work);
-
        adapter->ptp_clock = ptp_clock_register(&adapter->ptp_caps,
                                                &adapter->pdev->dev);
        if (IS_ERR(adapter->ptp_clock)) {
+               err = PTR_ERR(adapter->ptp_clock);
                adapter->ptp_clock = NULL;
                e_dev_err("ptp_clock_register failed\n");
+               return err;
        } else
                e_dev_info("registered PHC device on %s\n", netdev->name);
 
+       /* set default timestamp mode to disabled here. We do this in
+        * create_clock instead of init, because we don't want to override the
+        * previous settings during a resume cycle.
+        */
        adapter->tstamp_config.rx_filter = HWTSTAMP_FILTER_NONE;
        adapter->tstamp_config.tx_type = HWTSTAMP_TX_OFF;
+
+       return 0;
+}
+
+/**
+ * ixgbe_ptp_init
+ * @adapter: the ixgbe private adapter structure
+ *
+ * This function performs the required steps for enabling PTP
+ * support. If PTP support has already been loaded it simply calls the
+ * cyclecounter init routine and exits.
+ */
+void ixgbe_ptp_init(struct ixgbe_adapter *adapter)
+{
+       /* initialize the spin lock first since we can't control when a user
+        * will call the entry functions once we have initialized the clock
+        * device
+        */
+       spin_lock_init(&adapter->tmreg_lock);
+
+       /* obtain a PTP device, or re-use an existing device */
+       if (ixgbe_ptp_create_clock(adapter))
+               return;
+
+       /* we have a clock so we can initialize work now */
+       INIT_WORK(&adapter->ptp_tx_work, ixgbe_ptp_tx_hwtstamp_work);
+
+       /* reset the PTP related hardware bits */
        ixgbe_ptp_reset(adapter);
 
        /* enter the IXGBE_PTP_RUNNING state */