1 files changed, 31 insertions, 17 deletions

diff --git a/drivers/platform/mellanox/mlxreg-hotplug.c b/drivers/platform/mellanox/mlxreg-hotplug.c
index b56953ae1ab8..922913b8870f 100644
--- a/drivers/platform/mellanox/mlxreg-hotplug.c
+++ b/drivers/platform/mellanox/mlxreg-hotplug.c
@@ -55,6 +55,7 @@
 #define MLXREG_HOTPLUG_RST_CNTR		3
 
 #define MLXREG_HOTPLUG_ATTRS_MAX	24
+#define MLXREG_HOTPLUG_NOT_ASSERT	3
 
 /**
  * struct mlxreg_hotplug_priv_data - platform private data:
@@ -74,6 +75,7 @@
  * @mask: top aggregation interrupt common mask;
  * @aggr_cache: last value of aggregation register status;
  * @after_probe: flag indication probing completion;
+ * @not_asserted: number of entries in workqueue with no signal assertion;
  */
 struct mlxreg_hotplug_priv_data {
 	int irq;
@@ -93,6 +95,7 @@ struct mlxreg_hotplug_priv_data {
 	u32 mask;
 	u32 aggr_cache;
 	bool after_probe;
+	u8 not_asserted;
 };
 
 static int mlxreg_hotplug_device_create(struct mlxreg_hotplug_priv_data *priv,
@@ -410,6 +413,18 @@ static void mlxreg_hotplug_work_handler(struct work_struct *work)
 	aggr_asserted = priv->aggr_cache ^ regval;
 	priv->aggr_cache = regval;
 
+	/*
+	 * Handler is invoked, but no assertion is detected at top aggregation
+	 * status level. Set aggr_asserted to mask value to allow handler extra
+	 * run over all relevant signals to recover any missed signal.
+	 */
+	if (priv->not_asserted == MLXREG_HOTPLUG_NOT_ASSERT) {
+		priv->not_asserted = 0;
+		aggr_asserted = pdata->mask;
+	}
+	if (!aggr_asserted)
+		goto unmask_event;
+
 	/* Handle topology and health configuration changes. */
 	for (i = 0; i < pdata->counter; i++, item++) {
 		if (aggr_asserted & item->aggr_mask) {
@@ -420,27 +435,26 @@ static void mlxreg_hotplug_work_handler(struct work_struct *work)
 		}
 	}
 
-	if (aggr_asserted) {
-		spin_lock_irqsave(&priv->lock, flags);
+	spin_lock_irqsave(&priv->lock, flags);
 
-		/*
-		 * It is possible, that some signals have been inserted, while
-		 * interrupt has been masked by mlxreg_hotplug_work_handler.
-		 * In this case such signals will be missed. In order to handle
-		 * these signals delayed work is canceled and work task
-		 * re-scheduled for immediate execution. It allows to handle
-		 * missed signals, if any. In other case work handler just
-		 * validates that no new signals have been received during
-		 * masking.
-		 */
-		cancel_delayed_work(&priv->dwork_irq);
-		schedule_delayed_work(&priv->dwork_irq, 0);
+	/*
+	 * It is possible, that some signals have been inserted, while
+	 * interrupt has been masked by mlxreg_hotplug_work_handler. In this
+	 * case such signals will be missed. In order to handle these signals
+	 * delayed work is canceled and work task re-scheduled for immediate
+	 * execution. It allows to handle missed signals, if any. In other case
+	 * work handler just validates that no new signals have been received
+	 * during masking.
+	 */
+	cancel_delayed_work(&priv->dwork_irq);
+	schedule_delayed_work(&priv->dwork_irq, 0);
 
-		spin_unlock_irqrestore(&priv->lock, flags);
+	spin_unlock_irqrestore(&priv->lock, flags);
 
-		return;
-	}
+	return;
 
+unmask_event:
+	priv->not_asserted++;
 	/* Unmask aggregation event (no need acknowledge). */
 	ret = regmap_write(priv->regmap, pdata->cell +
 			   MLXREG_HOTPLUG_AGGR_MASK_OFF, pdata->mask);