qcacmn: Integrate tasklet flushing logic into snoc

Need to ensure that that the wakeup message gets processed
deterministically (before the return of hif_bus_suspend,
or after the message has woken up the apps.)

In another change, the driver will check for the wakeup message
after hif_bus_suspend completes and reject the suspend if it
has allready recieve the wakeup message. In conjunction with
this change the host will not be able to accidentally process
and discard the wakeup message.

Change-Id: I6d487a00dcfd40a665d3be03697f3a7cfc815203
CRs-Fixed: 1051968

hif/src/snoc/if_snoc.c

@@ -376,22 +376,107 @@ QDF_STATUS hif_snoc_setup_wakeup_sources(struct hif_softc *scn, bool enable)
 	return QDF_STATUS_SUCCESS;
 }
 
+/**
+ * __hif_snoc_irq_state_vote() - enable/disable all the ce interrupts
+ * @scn: hif context pointer
+ * @enble: true to enable the interrupts false to disable
+ *
+ * takes care of unwinding partial successes.
+ *
+ * Return: QDF_STATUS_SUCCESS on success
+ */
+
+static QDF_STATUS __hif_snoc_irq_state_vote(struct hif_softc *scn, bool enable)
+{
+	int num_ce = scn->ce_count;
+	int ce_id = 0;
+	int irq;
+
+	while (ce_id < num_ce) {
+		irq = icnss_get_irq(ce_id);
+		if (irq < 0)
+			goto error;
+
+		if (enable)
+			enable_irq(irq);
+		else
+			disable_irq(irq);
+
+		ce_id++;
+	}
+
+	return QDF_STATUS_SUCCESS;
+
+error:
+	HIF_ERROR("%s: failed to map ce to irq", __func__);
+
+	while (--ce_id >= 0) {
+		irq = icnss_get_irq(ce_id);
+		if (irq < 0)
+			continue;
+
+		if (enable)
+			disable_irq(irq);
+		else
+			enable_irq(irq);
+	}
+	return QDF_STATUS_E_FAULT;
+}
+
+/**
+ * hif_snoc_enable_irqs() - enable the ce irqs
+ * @scn: hif context
+ *
+ * Return: QDF_STATUS_SUCCESS on success
+ */
+static QDF_STATUS hif_snoc_enable_irqs(struct hif_softc *scn)
+{
+	return __hif_snoc_irq_state_vote(scn, true);
+}
 
+/**
+ * hif_snoc_enable_irqs() - enable the ce irqs
+ * @scn: hif context
+ *
+ * Return: QDF_STATUS_SUCCESS on success
+ */
+static QDF_STATUS hif_snoc_disable_irqs(struct hif_softc *scn)
+{
+	return __hif_snoc_irq_state_vote(scn, false);
+}
 
 /**
  * hif_snoc_bus_suspend() - prepare to suspend the bus
  * @scn: hif context
  *
  * Setup wakeup interrupt configuration.
+ * Disable CE interrupts (wakeup interrupt will still wake apps)
+ * Drain tasklets. - make sure that we don't suspend while processing
+ * the wakeup message.
  *
  * Return: 0 on success.
  */
 int hif_snoc_bus_suspend(struct hif_softc *scn)
 {
 	if (hif_snoc_setup_wakeup_sources(scn, true) != QDF_STATUS_SUCCESS)
-		return -EFAULT;
+		goto error;
+
+	if (hif_snoc_disable_irqs(scn) != QDF_STATUS_SUCCESS)
+		goto wakeup_sources;
 
+	if (hif_drain_tasklets(scn) != 0)
+		goto enable_irqs;
 	return 0;
+
+enable_irqs:
+	if (hif_snoc_enable_irqs(scn) != QDF_STATUS_SUCCESS)
+		QDF_BUG(0);
+wakeup_sources:
+	if (hif_snoc_setup_wakeup_sources(scn, false) != QDF_STATUS_SUCCESS)
+		QDF_BUG(0);
+error:
+	return -EFAULT;
+
 }
 
 /**
@@ -399,6 +484,7 @@ int hif_snoc_bus_suspend(struct hif_softc *scn)
  * @scn: hif context
  *
  * Clear wakeup interrupt configuration.
+ * Reenable ce interrupts
  *
  * Return: 0 on success
  */
@@ -407,5 +493,8 @@ int hif_snoc_bus_resume(struct hif_softc *scn)
 	if (hif_snoc_setup_wakeup_sources(scn, false) != QDF_STATUS_SUCCESS)
 		QDF_BUG(0);
 
+	if (hif_snoc_enable_irqs(scn) != QDF_STATUS_SUCCESS)
+		QDF_BUG(0);
+
 	return 0;
 }