iwlwifi: cleanup iwl_good_plcp_health

Make iwl_good_plcp_health code easiest to read.

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Acked-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --git a/drivers/net/wireless/iwlwifi/iwl-rx.c b/drivers/net/wireless/iwlwifi/iwl-rx.c
index 8dc1294..a70f1eb 100644 (file)
--- a/drivers/net/wireless/iwlwifi/iwl-rx.c
+++ b/drivers/net/wireless/iwlwifi/iwl-rx.c
@@ -451,82 +451,57 @@ static bool iwl_good_ack_health(struct iwl_priv *priv, struct iwl_rx_packet *pkt
 static bool iwl_good_plcp_health(struct iwl_priv *priv,
                                 struct iwl_rx_packet *pkt)
 {
-       bool rc = true;
-       int combined_plcp_delta;
-       unsigned int plcp_msec;
-       unsigned long plcp_received_jiffies;
+       unsigned int msecs;
+       unsigned long stamp;
+       int delta;
+       int threshold = priv->cfg->base_params->plcp_delta_threshold;
 
-       if (priv->cfg->base_params->plcp_delta_threshold ==
-           IWL_MAX_PLCP_ERR_THRESHOLD_DISABLE) {
+       if (threshold == IWL_MAX_PLCP_ERR_THRESHOLD_DISABLE) {
                IWL_DEBUG_RADIO(priv, "plcp_err check disabled\n");
-               return rc;
+               return true;
        }
 
-       /*
-        * check for plcp_err and trigger radio reset if it exceeds
-        * the plcp error threshold plcp_delta.
-        */
-       plcp_received_jiffies = jiffies;
-       plcp_msec = jiffies_to_msecs((long) plcp_received_jiffies -
-                                       (long) priv->plcp_jiffies);
-       priv->plcp_jiffies = plcp_received_jiffies;
-       /*
-        * check to make sure plcp_msec is not 0 to prevent division
-        * by zero.
-        */
-       if (plcp_msec) {
-               struct statistics_rx_phy *ofdm;
-               struct statistics_rx_ht_phy *ofdm_ht;
-
-               if (iwl_bt_statistics(priv)) {
-                       ofdm = &pkt->u.stats_bt.rx.ofdm;
-                       ofdm_ht = &pkt->u.stats_bt.rx.ofdm_ht;
-                       combined_plcp_delta =
-                          (le32_to_cpu(ofdm->plcp_err) -
-                          le32_to_cpu(priv->_agn.statistics_bt.
-                                      rx.ofdm.plcp_err)) +
-                          (le32_to_cpu(ofdm_ht->plcp_err) -
-                          le32_to_cpu(priv->_agn.statistics_bt.
-                                      rx.ofdm_ht.plcp_err));
-               } else {
-                       ofdm = &pkt->u.stats.rx.ofdm;
-                       ofdm_ht = &pkt->u.stats.rx.ofdm_ht;
-                       combined_plcp_delta =
-                           (le32_to_cpu(ofdm->plcp_err) -
-                           le32_to_cpu(priv->_agn.statistics.
-                                       rx.ofdm.plcp_err)) +
-                           (le32_to_cpu(ofdm_ht->plcp_err) -
-                           le32_to_cpu(priv->_agn.statistics.
-                                       rx.ofdm_ht.plcp_err));
-               }
+       stamp = jiffies;
+       msecs = jiffies_to_msecs(stamp - priv->plcp_jiffies);
+       priv->plcp_jiffies = stamp;
 
-               if ((combined_plcp_delta > 0) &&
-                   ((combined_plcp_delta * 100) / plcp_msec) >
-                       priv->cfg->base_params->plcp_delta_threshold) {
-                       /*
-                        * if plcp_err exceed the threshold,
-                        * the following data is printed in csv format:
-                        *    Text: plcp_err exceeded %d,
-                        *    Received ofdm.plcp_err,
-                        *    Current ofdm.plcp_err,
-                        *    Received ofdm_ht.plcp_err,
-                        *    Current ofdm_ht.plcp_err,
-                        *    combined_plcp_delta,
-                        *    plcp_msec
-                        */
-                       IWL_DEBUG_RADIO(priv, "plcp_err exceeded %u, "
-                               "%u, %u, %u, %u, %d, %u mSecs\n",
-                               priv->cfg->base_params->plcp_delta_threshold,
-                               le32_to_cpu(ofdm->plcp_err),
-                               le32_to_cpu(ofdm->plcp_err),
-                               le32_to_cpu(ofdm_ht->plcp_err),
-                               le32_to_cpu(ofdm_ht->plcp_err),
-                               combined_plcp_delta, plcp_msec);
-
-                       rc = false;
-               }
+       if (msecs == 0)
+               return true;
+
+       if (iwl_bt_statistics(priv)) {
+               struct statistics_rx_bt *cur, *old;
+
+               cur = &pkt->u.stats_bt.rx;
+               old = &priv->_agn.statistics_bt.rx;
+
+               delta = le32_to_cpu(cur->ofdm.plcp_err) -
+                       le32_to_cpu(old->ofdm.plcp_err) +
+                       le32_to_cpu(cur->ofdm_ht.plcp_err) -
+                       le32_to_cpu(old->ofdm_ht.plcp_err);
+       } else {
+               struct statistics_rx *cur, *old;
+
+               cur = &pkt->u.stats.rx;
+               old = &priv->_agn.statistics.rx;
+
+               delta = le32_to_cpu(cur->ofdm.plcp_err) -
+                       le32_to_cpu(old->ofdm.plcp_err) +
+                       le32_to_cpu(cur->ofdm_ht.plcp_err) -
+                       le32_to_cpu(old->ofdm_ht.plcp_err);
        }
-       return rc;
+
+       /* Can be negative if firmware reseted statistics */
+       if (delta <= 0)
+               return true;
+
+       if ((delta * 100 / msecs) > threshold) {
+               IWL_DEBUG_RADIO(priv,
+                               "plcp health threshold %u delta %d msecs %u\n",
+                               threshold, delta, msecs);
+               return false;
+       }
+
+       return true;
 }
 
 static void iwl_recover_from_statistics(struct iwl_priv *priv,