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>

1 files changed, 45 insertions, 70 deletions

diff --git a/drivers/net/wireless/iwlwifi/iwl-rx.c b/drivers/net/wireless/iwlwifi/iwl-rx.c
index 8dc129499b90..a70f1eb08e5c 100644
--- 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,