mmc: core: Hold a wake lock accross delayed work + mmc rescan
San Mehat [Mon, 23 Mar 2009 19:20:37 +0000 (12:20 -0700)]
Signed-off-by: San Mehat <san@android.com>

mmc: core: Rework mmc_delayed_work wakelock so that the wakelock is only extended if a card is added or removed.

Signed-off-by: San Mehat <san@google.com>

drivers/mmc/core/core.c

index c57a283..5db69d8 100644 (file)
@@ -27,6 +27,7 @@
 #include <linux/fault-inject.h>
 #include <linux/random.h>
 #include <linux/slab.h>
+#include <linux/wakelock.h>
 
 #include <linux/mmc/card.h>
 #include <linux/mmc/host.h>
@@ -52,6 +53,7 @@
 #define MMC_BKOPS_MAX_TIMEOUT  (4 * 60 * 1000) /* max time to wait in ms */
 
 static struct workqueue_struct *workqueue;
+static struct wake_lock mmc_delayed_work_wake_lock;
 static const unsigned freqs[] = { 400000, 300000, 200000, 100000 };
 
 /*
@@ -85,6 +87,7 @@ MODULE_PARM_DESC(
 static int mmc_schedule_delayed_work(struct delayed_work *work,
                                     unsigned long delay)
 {
+       wake_lock(&mmc_delayed_work_wake_lock);
        return queue_delayed_work(workqueue, work, delay);
 }
 
@@ -2351,6 +2354,7 @@ void mmc_rescan(struct work_struct *work)
        struct mmc_host *host =
                container_of(work, struct mmc_host, detect.work);
        int i;
+       bool extend_wakelock = false;
 
        if (host->rescan_disable)
                return;
@@ -2400,14 +2404,20 @@ void mmc_rescan(struct work_struct *work)
 
        mmc_claim_host(host);
        for (i = 0; i < ARRAY_SIZE(freqs); i++) {
-               if (!mmc_rescan_try_freq(host, max(freqs[i], host->f_min)))
+               if (!mmc_rescan_try_freq(host, max(freqs[i], host->f_min))) {
+                       extend_wakelock = true;
                        break;
+               }
                if (freqs[i] <= host->f_min)
                        break;
        }
        mmc_release_host(host);
 
  out:
+       if (extend_wakelock)
+               wake_lock_timeout(&mmc_delayed_work_wake_lock, HZ / 2);
+       else
+               wake_unlock(&mmc_delayed_work_wake_lock);
        if (host->caps & MMC_CAP_NEEDS_POLL)
                mmc_schedule_delayed_work(&host->detect, HZ);
 }
@@ -2813,6 +2823,9 @@ static int __init mmc_init(void)
        if (!workqueue)
                return -ENOMEM;
 
+       wake_lock_init(&mmc_delayed_work_wake_lock, WAKE_LOCK_SUSPEND,
+                      "mmc_delayed_work");
+
        ret = mmc_register_bus();
        if (ret)
                goto destroy_workqueue;
@@ -2833,6 +2846,7 @@ unregister_bus:
        mmc_unregister_bus();
 destroy_workqueue:
        destroy_workqueue(workqueue);
+       wake_lock_destroy(&mmc_delayed_work_wake_lock);
 
        return ret;
 }
@@ -2843,6 +2857,7 @@ static void __exit mmc_exit(void)
        mmc_unregister_host_class();
        mmc_unregister_bus();
        destroy_workqueue(workqueue);
+       wake_lock_destroy(&mmc_delayed_work_wake_lock);
 }
 
 subsys_initcall(mmc_init);