mmc: core: Hold a wake lock accross delayed work + mmc rescan

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>

1 files changed, 15 insertions, 0 deletions

diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index e543f85deb79..08d08e4699e7 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -22,6 +22,7 @@
 #include <linux/scatterlist.h>
 #include <linux/log2.h>
 #include <linux/regulator/consumer.h>
+#include <linux/wakelock.h>
 
 #include <linux/mmc/card.h>
 #include <linux/mmc/host.h>
@@ -38,6 +39,7 @@
 #include "sdio_ops.h"
 
 static struct workqueue_struct *workqueue;
+static struct wake_lock mmc_delayed_work_wake_lock;
 
 /*
  * Enabling software CRCs on the data blocks can be a significant (30%)
@@ -53,6 +55,7 @@ module_param(use_spi_crc, bool, 0);
 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);
 }
 
@@ -1041,6 +1044,7 @@ void mmc_rescan(struct work_struct *work)
 		container_of(work, struct mmc_host, detect.work);
 	u32 ocr;
 	int err;
+	int extend_wakelock = 0;
 
 	mmc_bus_get(host);
 
@@ -1084,6 +1088,7 @@ void mmc_rescan(struct work_struct *work)
 	if (!err) {
 		if (mmc_attach_sdio(host, ocr))
 			mmc_power_off(host);
+		extend_wakelock = 1;
 		goto out;
 	}
 
@@ -1094,6 +1099,7 @@ void mmc_rescan(struct work_struct *work)
 	if (!err) {
 		if (mmc_attach_sd(host, ocr))
 			mmc_power_off(host);
+		extend_wakelock = 1;
 		goto out;
 	}
 
@@ -1104,6 +1110,7 @@ void mmc_rescan(struct work_struct *work)
 	if (!err) {
 		if (mmc_attach_mmc(host, ocr))
 			mmc_power_off(host);
+		extend_wakelock = 1;
 		goto out;
 	}
 
@@ -1111,6 +1118,11 @@ void mmc_rescan(struct work_struct *work)
 	mmc_power_off(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);
 }
@@ -1332,6 +1344,8 @@ static int __init mmc_init(void)
 {
 	int ret;
 
+	wake_lock_init(&mmc_delayed_work_wake_lock, WAKE_LOCK_SUSPEND, "mmc_delayed_work");
+
 	workqueue = create_singlethread_workqueue("kmmcd");
 	if (!workqueue)
 		return -ENOMEM;
@@ -1366,6 +1380,7 @@ 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);