wl12xx: prevent scheduling while suspending (WoW enabled)

When WoW is enabled, the interface will stay up and the chip will
be powered on, so we have to flush/cancel any remaining work, and
prevent the irq handler from scheduling a new work until the system
is resumed.

Add 2 new flags:
* WL1271_FLAG_SUSPENDED - the system is (about to be) suspended.
* WL1271_FLAG_PENDING_WORK - there is a pending irq work which
   should be scheduled when the system is being resumed.

In order to wake-up the system while getting an irq, we initialize
the device as wakeup device, and calling pm_wakeup_event() upon
getting the interrupt (while the system is about to be suspended)

Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Luciano Coelho <coelho@ti.com>

diff --git a/drivers/net/wireless/wl12xx/main.c b/drivers/net/wireless/wl12xx/main.c
index 4b421d8..8f9e615 100644 (file)
--- a/drivers/net/wireless/wl12xx/main.c
+++ b/drivers/net/wireless/wl12xx/main.c
@@ -1356,6 +1356,28 @@ static int wl1271_op_suspend(struct ieee80211_hw *hw,
        struct wl1271 *wl = hw->priv;
        wl1271_debug(DEBUG_MAC80211, "mac80211 suspend wow=%d", !!wow);
        wl->wow_enabled = !!wow;
+       if (wl->wow_enabled) {
+               /* flush any remaining work */
+               wl1271_debug(DEBUG_MAC80211, "flushing remaining works");
+               flush_delayed_work(&wl->scan_complete_work);
+
+               /*
+                * disable and re-enable interrupts in order to flush
+                * the threaded_irq
+                */
+               wl1271_disable_interrupts(wl);
+
+               /*
+                * set suspended flag to avoid triggering a new threaded_irq
+                * work. no need for spinlock as interrupts are disabled.
+                */
+               set_bit(WL1271_FLAG_SUSPENDED, &wl->flags);
+
+               wl1271_enable_interrupts(wl);
+               flush_work(&wl->tx_work);
+               flush_delayed_work(&wl->pspoll_work);
+               flush_delayed_work(&wl->elp_work);
+       }
        return 0;
 }
 
@@ -1364,6 +1386,30 @@ static int wl1271_op_resume(struct ieee80211_hw *hw)
        struct wl1271 *wl = hw->priv;
        wl1271_debug(DEBUG_MAC80211, "mac80211 resume wow=%d",
                     wl->wow_enabled);
+
+       /*
+        * re-enable irq_work enqueuing, and call irq_work directly if
+        * there is a pending work.
+        */
+       if (wl->wow_enabled) {
+               struct wl1271 *wl = hw->priv;
+               unsigned long flags;
+               bool run_irq_work = false;
+
+               spin_lock_irqsave(&wl->wl_lock, flags);
+               clear_bit(WL1271_FLAG_SUSPENDED, &wl->flags);
+               if (test_and_clear_bit(WL1271_FLAG_PENDING_WORK, &wl->flags))
+                       run_irq_work = true;
+               spin_unlock_irqrestore(&wl->wl_lock, flags);
+
+               if (run_irq_work) {
+                       wl1271_debug(DEBUG_MAC80211,
+                                    "run postponed irq_work directly");
+                       wl1271_irq(0, wl);
+                       wl1271_enable_interrupts(wl);
+               }
+       }
+
        return 0;
 }
 

diff --git a/drivers/net/wireless/wl12xx/sdio.c b/drivers/net/wireless/wl12xx/sdio.c
index 5b03fd5..41183db 100644 (file)
--- a/drivers/net/wireless/wl12xx/sdio.c
+++ b/drivers/net/wireless/wl12xx/sdio.c
@@ -82,6 +82,16 @@ static irqreturn_t wl1271_hardirq(int irq, void *cookie)
                complete(wl->elp_compl);
                wl->elp_compl = NULL;
        }
+
+       if (test_bit(WL1271_FLAG_SUSPENDED, &wl->flags)) {
+               /* don't enqueue a work right now. mark it as pending */
+               set_bit(WL1271_FLAG_PENDING_WORK, &wl->flags);
+               wl1271_debug(DEBUG_IRQ, "should not enqueue work");
+               disable_irq_nosync(wl->irq);
+               pm_wakeup_event(wl1271_sdio_wl_to_dev(wl), 0);
+               spin_unlock_irqrestore(&wl->wl_lock, flags);
+               return IRQ_HANDLED;
+       }
        spin_unlock_irqrestore(&wl->wl_lock, flags);
 
        return IRQ_WAKE_THREAD;
@@ -268,6 +278,7 @@ static int __devinit wl1271_probe(struct sdio_func *func,
        }
 
        enable_irq_wake(wl->irq);
+       device_init_wakeup(wl1271_sdio_wl_to_dev(wl), 1);
 
        disable_irq(wl->irq);
 
@@ -305,6 +316,7 @@ static void __devexit wl1271_remove(struct sdio_func *func)
        pm_runtime_get_noresume(&func->dev);
 
        wl1271_unregister_hw(wl);
+       device_init_wakeup(wl1271_sdio_wl_to_dev(wl), 0);
        disable_irq_wake(wl->irq);
        free_irq(wl->irq, wl);
        wl1271_free_hw(wl);
@@ -339,6 +351,9 @@ static int wl1271_suspend(struct device *dev)
                        wl1271_error("error while trying to keep power");
                        goto out;
                }
+
+               /* release host */
+               sdio_release_host(func);
        }
 out:
        return ret;
@@ -346,6 +361,15 @@ out:
 
 static int wl1271_resume(struct device *dev)
 {
+       struct sdio_func *func = dev_to_sdio_func(dev);
+       struct wl1271 *wl = sdio_get_drvdata(func);
+
+       wl1271_debug(DEBUG_MAC80211, "wl1271 resume");
+       if (wl->wow_enabled) {
+               /* claim back host */
+               sdio_claim_host(func);
+       }
+
        return 0;
 }
 

diff --git a/drivers/net/wireless/wl12xx/wl12xx.h b/drivers/net/wireless/wl12xx/wl12xx.h
index 9629e90..2218b9c 100644 (file)
--- a/drivers/net/wireless/wl12xx/wl12xx.h
+++ b/drivers/net/wireless/wl12xx/wl12xx.h
@@ -357,6 +357,8 @@ enum wl12xx_flags {
        WL1271_FLAG_AP_STARTED,
        WL1271_FLAG_IF_INITIALIZED,
        WL1271_FLAG_DUMMY_PACKET_PENDING,
+       WL1271_FLAG_SUSPENDED,
+       WL1271_FLAG_PENDING_WORK,
 };
 
 struct wl1271_link {