mmc: update workqueue usages

Workqueue creation API has been updated and flush_scheduled_work() is
deprecated and scheduled to be removed.

* core/core.c: Use alloc_ordered_workqueue() instead of
  create_singlethread_workqueue().  This removes an unnecessary
  rescuer.

* host/omap.c: Create, use and flush mmc_omap_wq instead of the
  system_wq.

* Flush host->mmc_carddetect_work directly on removal instead of using
  flush_scheduled_work().

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Chris Ball <cjb@laptop.org>
Cc: linux-mmc@vger.kernel.org

drivers/mmc/core/core.c

@@ -1789,7 +1789,7 @@ static int __init mmc_init(void)
 {
 	int ret;
 
-	workqueue = create_singlethread_workqueue("kmmcd");
+	workqueue = alloc_ordered_workqueue("kmmcd", 0);
 	if (!workqueue)
 		return -ENOMEM;
 

drivers/mmc/host/omap.c

@@ -173,6 +173,8 @@ struct mmc_omap_host {
 	struct omap_mmc_platform_data *pdata;
 };
 
+static struct workqueue_struct *mmc_omap_wq;
+
 static void mmc_omap_fclk_offdelay(struct mmc_omap_slot *slot)
 {
 	unsigned long tick_ns;
@@ -289,7 +291,7 @@ static void mmc_omap_release_slot(struct mmc_omap_slot *slot, int clk_enabled)
 		host->next_slot = new_slot;
 		host->mmc = new_slot->mmc;
 		spin_unlock_irqrestore(&host->slot_lock, flags);
-		schedule_work(&host->slot_release_work);
+		queue_work(mmc_omap_wq, &host->slot_release_work);
 		return;
 	}
 
@@ -457,7 +459,7 @@ mmc_omap_xfer_done(struct mmc_omap_host *host, struct mmc_data *data)
 	}
 
 	host->stop_data = data;
-	schedule_work(&host->send_stop_work);
+	queue_work(mmc_omap_wq, &host->send_stop_work);
 }
 
 static void
@@ -637,7 +639,7 @@ mmc_omap_cmd_timer(unsigned long data)
 		OMAP_MMC_WRITE(host, IE, 0);
 		disable_irq(host->irq);
 		host->abort = 1;
-		schedule_work(&host->cmd_abort_work);
+		queue_work(mmc_omap_wq, &host->cmd_abort_work);
 	}
 	spin_unlock_irqrestore(&host->slot_lock, flags);
 }
@@ -826,7 +828,7 @@ static irqreturn_t mmc_omap_irq(int irq, void *dev_id)
 		host->abort = 1;
 		OMAP_MMC_WRITE(host, IE, 0);
 		disable_irq_nosync(host->irq);
-		schedule_work(&host->cmd_abort_work);
+		queue_work(mmc_omap_wq, &host->cmd_abort_work);
 		return IRQ_HANDLED;
 	}
 
@@ -1387,7 +1389,7 @@ static void mmc_omap_remove_slot(struct mmc_omap_slot *slot)
 
 	tasklet_kill(&slot->cover_tasklet);
 	del_timer_sync(&slot->cover_timer);
-	flush_scheduled_work();
+	flush_workqueue(mmc_omap_wq);
 
 	mmc_remove_host(mmc);
 	mmc_free_host(mmc);
@@ -1608,12 +1610,22 @@ static struct platform_driver mmc_omap_driver = {
 
 static int __init mmc_omap_init(void)
 {
-	return platform_driver_probe(&mmc_omap_driver, mmc_omap_probe);
+	int ret;
+
+	mmc_omap_wq = alloc_workqueue("mmc_omap", 0, 0);
+	if (!mmc_omap_wq)
+		return -ENOMEM;
+
+	ret = platform_driver_probe(&mmc_omap_driver, mmc_omap_probe);
+	if (ret)
+		destroy_workqueue(mmc_omap_wq);
+	return ret;
 }
 
 static void __exit mmc_omap_exit(void)
 {
 	platform_driver_unregister(&mmc_omap_driver);
+	destroy_workqueue(mmc_omap_wq);
 }
 
 module_init(mmc_omap_init);

drivers/mmc/host/omap_hsmmc.c

@@ -2290,7 +2290,7 @@ static int omap_hsmmc_remove(struct platform_device *pdev)
 		free_irq(host->irq, host);
 		if (mmc_slot(host).card_detect_irq)
 			free_irq(mmc_slot(host).card_detect_irq, host);
-		flush_scheduled_work();
+		flush_work_sync(&host->mmc_carddetect_work);
 
 		mmc_host_disable(host->mmc);
 		clk_disable(host->iclk);