Staging: sxg: Add watchdog timer for managing Link states for SXG driver

Add a watchdog timer to take care of link change notifications.
Link changes would now be handled asynchronously as they involve large delays.

Signed-off-by: LinSysSoft Sahara Team <saharaproj@linsyssoft.com>
Signed-off-by: Mithlesh Thukral <mithlesh@linsyssoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

2 files changed, 59 insertions, 16 deletions

diff --git a/drivers/staging/sxg/sxg.c b/drivers/staging/sxg/sxg.c
index c41dea0013b..dbda031d405 100644
--- a/drivers/staging/sxg/sxg.c
+++ b/drivers/staging/sxg/sxg.c
@@ -136,6 +136,9 @@ static int sxg_register_interrupt(struct adapter_t *adapter);
 static void sxg_remove_isr(struct adapter_t *adapter);
 static irqreturn_t sxg_isr(int irq, void *dev_id);
 
+static void sxg_watchdog(unsigned long data);
+static void sxg_update_link_status (struct work_struct *work);
+
 #define XXXTODO 0
 
 #if XXXTODO
@@ -1122,6 +1125,12 @@ static int sxg_entry_probe(struct pci_dev *pcidev,
 
         netif_napi_add(netdev, &adapter->napi,
                 sxg_poll, SXG_NETDEV_WEIGHT);
+        netdev->watchdog_timeo = 2 * HZ;
+        init_timer(&adapter->watchdog_timer);
+        adapter->watchdog_timer.function = &sxg_watchdog;
+        adapter->watchdog_timer.data = (unsigned long) adapter;
+        INIT_WORK(&adapter->update_link_status, sxg_update_link_status);
+
         DBG_ERROR
             ("sxg: %s addr 0x%lx, irq %d, MAC addr \
                 %02X:%02X:%02X:%02X:%02X:%02X\n",
@@ -1441,7 +1450,10 @@ static int sxg_process_isr(struct adapter_t *adapter, u32 MessageId)
         }
         /* Link event */
         if (Isr & SXG_ISR_LINK) {
-                sxg_link_event(adapter);
+                if (adapter->state != ADAPT_DOWN) {
+                        adapter->link_status_changed = 1;
+                        schedule_work(&adapter->update_link_status);
+                }
         }
         /* Debug - breakpoint hit */
         if (Isr & SXG_ISR_BREAK) {
@@ -2260,6 +2272,7 @@ int sxg_second_open(struct net_device * dev)
 
         sxg_register_intr(adapter);
         spin_unlock_irqrestore(&sxg_global.driver_lock, sxg_global.flags);
+        mod_timer(&adapter->watchdog_timer, jiffies);
         return (STATUS_SUCCESS);
 
 }
@@ -2312,27 +2325,28 @@ static int sxg_entry_halt(struct net_device *dev)
 
         RssIds = SXG_RSS_CPU_COUNT(adapter);
         IsrCount = adapter->msi_enabled ? RssIds : 1;
-
-        napi_disable(&adapter->napi);
+        /* Disable interrupts */
         spin_lock_irqsave(&sxg_global.driver_lock, sxg_global.flags);
-        DBG_ERROR("sxg: %s (%s) ENTER\n", __func__, dev->name);
-
-        WRITE_REG(adapter->UcodeRegs[0].RcvCmd, 0, true);
-        netif_stop_queue(adapter->netdev);
+        SXG_DISABLE_ALL_INTERRUPTS(adapter);
         adapter->state = ADAPT_DOWN;
         adapter->linkstate = LINK_DOWN;
-        adapter->devflags_prev = 0;
-        DBG_ERROR("sxg: %s (%s) set adapter[%p] state to ADAPT_DOWN(%d)\n",
-                  __func__, dev->name, adapter, adapter->state);
-
-        /* Disable interrupts */
-        SXG_DISABLE_ALL_INTERRUPTS(adapter);
 
         spin_unlock_irqrestore(&sxg_global.driver_lock, sxg_global.flags);
-
         sxg_deregister_interrupt(adapter);
         WRITE_REG(HwRegs->Reset, 0xDEAD, FLUSH);
         mdelay(5000);
+
+        del_timer_sync(&adapter->watchdog_timer);
+        netif_stop_queue(dev);
+        netif_carrier_off(dev);
+
+        napi_disable(&adapter->napi);
+
+        WRITE_REG(adapter->UcodeRegs[0].RcvCmd, 0, true);
+        adapter->devflags_prev = 0;
+        DBG_ERROR("sxg: %s (%s) set adapter[%p] state to ADAPT_DOWN(%d)\n",
+                  __func__, dev->name, adapter, adapter->state);
+
         spin_lock(&adapter->RcvQLock);
         /* Free all the blocks and the buffers, moved from remove() routine */
         if (!(IsListEmpty(&adapter->AllRcvBlocks))) {
@@ -3013,6 +3027,8 @@ static void sxg_link_event(struct adapter_t *adapter)
         int status;
         u32 Value;
 
+        if (adapter->state == ADAPT_DOWN)
+                return;
         SXG_TRACE(TRACE_SXG, SxgTraceBuffer, TRACE_NOISY, "LinkEvnt",
                   adapter, 0, 0, 0);
         DBG_ERROR("ENTER %s\n", __func__);
@@ -3053,10 +3069,13 @@ static void sxg_link_event(struct adapter_t *adapter)
                 sxg_link_state(adapter, LinkState);
                 DBG_ERROR("SXG: Link Alarm occurred.  Link is %s\n",
                           ((LinkState == SXG_LINK_UP) ? "UP" : "DOWN"));
-                if (LinkState == SXG_LINK_UP)
+                if (LinkState == SXG_LINK_UP) {
                         netif_carrier_on(netdev);
-                else
+                        netif_tx_start_all_queues(netdev);
+                } else {
+                        netif_tx_stop_all_queues(netdev);
                         netif_carrier_off(netdev);
+                }
         } else {
                 /*
                  * XXXTODO - Assuming Link Attention is only being generated
@@ -4435,6 +4454,27 @@ static struct net_device_stats *sxg_get_stats(struct net_device * dev)
         return (&adapter->stats);
 }
 
+static void sxg_watchdog(unsigned long data)
+{
+        struct adapter_t *adapter = (struct adapter_t *) data;
+
+        if (adapter->state != ADAPT_DOWN) {
+                sxg_link_event(adapter);
+                /* Reset the timer */
+                mod_timer(&adapter->watchdog_timer, round_jiffies(jiffies + 2 * HZ));
+        }
+}
+
+static void sxg_update_link_status (struct work_struct *work)
+{
+        struct adapter_t *adapter = (struct adapter_t *)container_of
+                                (work, struct adapter_t, update_link_status);
+        if (likely(adapter->link_status_changed)) {
+                sxg_link_event(adapter);
+                adapter->link_status_changed = 0;
+        }
+}
+
 static struct pci_driver sxg_driver = {
         .name = sxg_driver_name,
         .id_table = sxg_pci_tbl,
diff --git a/drivers/staging/sxg/sxg.h b/drivers/staging/sxg/sxg.h
index 899cf1510f9..f07aa708d86 100644
--- a/drivers/staging/sxg/sxg.h
+++ b/drivers/staging/sxg/sxg.h
@@ -715,6 +715,9 @@ struct adapter_t {
         /*MSI-X related data elements*/
         u32 nr_msix_entries;
         struct msix_entry *msi_entries;
+        struct timer_list watchdog_timer;
+        struct work_struct update_link_status;
+        u32     link_status_changed;
 };
 
 #if SLIC_DUMP_ENABLED