mmc: Convert from tasklet to BH workqueue

The only generic interface to execute asynchronously in the BH context is
tasklet; however, it's marked deprecated and has some design flaws. To
replace tasklets, BH workqueue support was recently added. A BH workqueue
behaves similarly to regular workqueues except that the queued work items
are executed in the BH context.

This patch converts drivers/mmc/* from tasklet to BH workqueue.

Based on the work done by Tejun Heo <tj@kernel.org>

Tested-by: Christian Loehle <christian.loehle@arm.com>
Tested-by: Aubin Constans <aubin.constans@microchip.com>
Acked-by: Aubin Constans <aubin.constans@microchip.com>
Acked-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Reviewed-by: Christian Loehle <christian.loehle@arm.com>
Signed-off-by: Allen Pais <allen.lkml@gmail.com>
Link: https://lore.kernel.org/r/20240701100736.4001658-1-allen.lkml@gmail.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

13 files changed, 142 insertions, 135 deletions

diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c
index 8199d9620075..6490df54a6f5 100644
--- a/drivers/mmc/host/atmel-mci.c
+++ b/drivers/mmc/host/atmel-mci.c
@@ -33,6 +33,7 @@
 #include <linux/pm.h>
 #include <linux/pm_runtime.h>
 #include <linux/pinctrl/consumer.h>
+#include <linux/workqueue.h>
 
 #include <asm/cacheflush.h>
 #include <asm/io.h>
@@ -272,12 +273,12 @@ struct atmel_mci_dma {
  *	EVENT_DATA_ERROR is pending.
  * @stop_cmdr: Value to be loaded into CMDR when the stop command is
  *	to be sent.
- * @tasklet: Tasklet running the request state machine.
+ * @bh_work: Work running the request state machine.
  * @pending_events: Bitmask of events flagged by the interrupt handler
- *	to be processed by the tasklet.
+ *	to be processed by the work.
  * @completed_events: Bitmask of events which the state machine has
  *	processed.
- * @state: Tasklet state.
+ * @state: Work state.
  * @queue: List of slots waiting for access to the controller.
  * @need_clock_update: Update the clock rate before the next request.
  * @need_reset: Reset controller before next request.
@@ -352,7 +353,7 @@ struct atmel_mci {
 	u32			data_status;
 	u32			stop_cmdr;
 
-	struct tasklet_struct	tasklet;
+	struct work_struct	bh_work;
 	unsigned long		pending_events;
 	unsigned long		completed_events;
 	enum atmel_mci_state	state;
@@ -735,7 +736,7 @@ static void atmci_timeout_timer(struct timer_list *t)
 	host->need_reset = 1;
 	host->state = STATE_END_REQUEST;
 	smp_wmb();
-	tasklet_schedule(&host->tasklet);
+	queue_work(system_bh_wq, &host->bh_work);
 }
 
 static inline unsigned int atmci_ns_to_clocks(struct atmel_mci *host,
@@ -958,7 +959,7 @@ static void atmci_pdc_complete(struct atmel_mci *host)
 
 	dev_dbg(dev, "(%s) set pending xfer complete\n", __func__);
 	atmci_set_pending(host, EVENT_XFER_COMPLETE);
-	tasklet_schedule(&host->tasklet);
+	queue_work(system_bh_wq, &host->bh_work);
 }
 
 static void atmci_dma_cleanup(struct atmel_mci *host)
@@ -972,7 +973,7 @@ static void atmci_dma_cleanup(struct atmel_mci *host)
 }
 
 /*
- * This function is called by the DMA driver from tasklet context.
+ * This function is called by the DMA driver from bh context.
  */
 static void atmci_dma_complete(void *arg)
 {
@@ -995,7 +996,7 @@ static void atmci_dma_complete(void *arg)
 	if (data) {
 		dev_dbg(dev, "(%s) set pending xfer complete\n", __func__);
 		atmci_set_pending(host, EVENT_XFER_COMPLETE);
-		tasklet_schedule(&host->tasklet);
+		queue_work(system_bh_wq, &host->bh_work);
 
 		/*
 		 * Regardless of what the documentation says, we have
@@ -1008,7 +1009,7 @@ static void atmci_dma_complete(void *arg)
 		 * haven't seen all the potential error bits yet.
 		 *
 		 * The interrupt handler will schedule a different
-		 * tasklet to finish things up when the data transfer
+		 * bh work to finish things up when the data transfer
 		 * is completely done.
 		 *
 		 * We may not complete the mmc request here anyway
@@ -1745,9 +1746,9 @@ static void atmci_detect_change(struct timer_list *t)
 	}
 }
 
-static void atmci_tasklet_func(struct tasklet_struct *t)
+static void atmci_work_func(struct work_struct *t)
 {
-	struct atmel_mci        *host = from_tasklet(host, t, tasklet);
+	struct atmel_mci        *host = from_work(host, t, bh_work);
 	struct mmc_request	*mrq = host->mrq;
 	struct mmc_data		*data = host->data;
 	struct device		*dev = host->dev;
@@ -1759,7 +1760,7 @@ static void atmci_tasklet_func(struct tasklet_struct *t)
 
 	state = host->state;
 
-	dev_vdbg(dev, "tasklet: state %u pending/completed/mask %lx/%lx/%x\n",
+	dev_vdbg(dev, "bh_work: state %u pending/completed/mask %lx/%lx/%x\n",
 		state, host->pending_events, host->completed_events,
 		atmci_readl(host, ATMCI_IMR));
 
@@ -2118,7 +2119,7 @@ static irqreturn_t atmci_interrupt(int irq, void *dev_id)
 			dev_dbg(dev, "set pending data error\n");
 			smp_wmb();
 			atmci_set_pending(host, EVENT_DATA_ERROR);
-			tasklet_schedule(&host->tasklet);
+			queue_work(system_bh_wq, &host->bh_work);
 		}
 
 		if (pending & ATMCI_TXBUFE) {
@@ -2187,7 +2188,7 @@ static irqreturn_t atmci_interrupt(int irq, void *dev_id)
 			smp_wmb();
 			dev_dbg(dev, "set pending notbusy\n");
 			atmci_set_pending(host, EVENT_NOTBUSY);
-			tasklet_schedule(&host->tasklet);
+			queue_work(system_bh_wq, &host->bh_work);
 		}
 
 		if (pending & ATMCI_NOTBUSY) {
@@ -2196,7 +2197,7 @@ static irqreturn_t atmci_interrupt(int irq, void *dev_id)
 			smp_wmb();
 			dev_dbg(dev, "set pending notbusy\n");
 			atmci_set_pending(host, EVENT_NOTBUSY);
-			tasklet_schedule(&host->tasklet);
+			queue_work(system_bh_wq, &host->bh_work);
 		}
 
 		if (pending & ATMCI_RXRDY)
@@ -2211,7 +2212,7 @@ static irqreturn_t atmci_interrupt(int irq, void *dev_id)
 			smp_wmb();
 			dev_dbg(dev, "set pending cmd rdy\n");
 			atmci_set_pending(host, EVENT_CMD_RDY);
-			tasklet_schedule(&host->tasklet);
+			queue_work(system_bh_wq, &host->bh_work);
 		}
 
 		if (pending & (ATMCI_SDIOIRQA | ATMCI_SDIOIRQB))
@@ -2487,7 +2488,7 @@ static int atmci_probe(struct platform_device *pdev)
 
 	host->mapbase = regs->start;
 
-	tasklet_setup(&host->tasklet, atmci_tasklet_func);
+	INIT_WORK(&host->bh_work, atmci_work_func);
 
 	ret = request_irq(irq, atmci_interrupt, 0, dev_name(dev), host);
 	if (ret) {
diff --git a/drivers/mmc/host/au1xmmc.c b/drivers/mmc/host/au1xmmc.c
index b5a5c6a2fe8b..6e80bcb668ec 100644
--- a/drivers/mmc/host/au1xmmc.c
+++ b/drivers/mmc/host/au1xmmc.c
@@ -42,6 +42,7 @@
 #include <linux/leds.h>
 #include <linux/mmc/host.h>
 #include <linux/slab.h>
+#include <linux/workqueue.h>
 
 #include <asm/io.h>
 #include <asm/mach-au1x00/au1000.h>
@@ -113,8 +114,8 @@ struct au1xmmc_host {
 
 	int irq;
 
-	struct tasklet_struct finish_task;
-	struct tasklet_struct data_task;
+	struct work_struct finish_bh_work;
+	struct work_struct data_bh_work;
 	struct au1xmmc_platform_data *platdata;
 	struct platform_device *pdev;
 	struct resource *ioarea;
@@ -253,9 +254,9 @@ static void au1xmmc_finish_request(struct au1xmmc_host *host)
 	mmc_request_done(host->mmc, mrq);
 }
 
-static void au1xmmc_tasklet_finish(struct tasklet_struct *t)
+static void au1xmmc_finish_bh_work(struct work_struct *t)
 {
-	struct au1xmmc_host *host = from_tasklet(host, t, finish_task);
+	struct au1xmmc_host *host = from_work(host, t, finish_bh_work);
 	au1xmmc_finish_request(host);
 }
 
@@ -363,9 +364,9 @@ static void au1xmmc_data_complete(struct au1xmmc_host *host, u32 status)
 	au1xmmc_finish_request(host);
 }
 
-static void au1xmmc_tasklet_data(struct tasklet_struct *t)
+static void au1xmmc_data_bh_work(struct work_struct *t)
 {
-	struct au1xmmc_host *host = from_tasklet(host, t, data_task);
+	struct au1xmmc_host *host = from_work(host, t, data_bh_work);
 
 	u32 status = __raw_readl(HOST_STATUS(host));
 	au1xmmc_data_complete(host, status);
@@ -425,7 +426,7 @@ static void au1xmmc_send_pio(struct au1xmmc_host *host)
 		if (host->flags & HOST_F_STOP)
 			SEND_STOP(host);
 
-		tasklet_schedule(&host->data_task);
+		queue_work(system_bh_wq, &host->data_bh_work);
 	}
 }
 
@@ -505,7 +506,7 @@ static void au1xmmc_receive_pio(struct au1xmmc_host *host)
 		if (host->flags & HOST_F_STOP)
 			SEND_STOP(host);
 
-		tasklet_schedule(&host->data_task);
+		queue_work(system_bh_wq, &host->data_bh_work);
 	}
 }
 
@@ -561,7 +562,7 @@ static void au1xmmc_cmd_complete(struct au1xmmc_host *host, u32 status)
 
 	if (!trans || cmd->error) {
 		IRQ_OFF(host, SD_CONFIG_TH | SD_CONFIG_RA | SD_CONFIG_RF);
-		tasklet_schedule(&host->finish_task);
+		queue_work(system_bh_wq, &host->finish_bh_work);
 		return;
 	}
 
@@ -797,7 +798,7 @@ static irqreturn_t au1xmmc_irq(int irq, void *dev_id)
 		IRQ_OFF(host, SD_CONFIG_NE | SD_CONFIG_TH);
 
 		/* IRQ_OFF(host, SD_CONFIG_TH | SD_CONFIG_RA | SD_CONFIG_RF); */
-		tasklet_schedule(&host->finish_task);
+		queue_work(system_bh_wq, &host->finish_bh_work);
 	}
 #if 0
 	else if (status & SD_STATUS_DD) {
@@ -806,7 +807,7 @@ static irqreturn_t au1xmmc_irq(int irq, void *dev_id)
 			au1xmmc_receive_pio(host);
 		else {
 			au1xmmc_data_complete(host, status);
-			/* tasklet_schedule(&host->data_task); */
+			/* queue_work(system_bh_wq, &host->data_bh_work); */
 		}
 	}
 #endif
@@ -854,7 +855,7 @@ static void au1xmmc_dbdma_callback(int irq, void *dev_id)
 	if (host->flags & HOST_F_STOP)
 		SEND_STOP(host);
 
-	tasklet_schedule(&host->data_task);
+	queue_work(system_bh_wq, &host->data_bh_work);
 }
 
 static int au1xmmc_dbdma_init(struct au1xmmc_host *host)
@@ -1039,9 +1040,9 @@ static int au1xmmc_probe(struct platform_device *pdev)
 	if (host->platdata)
 		mmc->caps &= ~(host->platdata->mask_host_caps);
 
-	tasklet_setup(&host->data_task, au1xmmc_tasklet_data);
+	INIT_WORK(&host->data_bh_work, au1xmmc_data_bh_work);
 
-	tasklet_setup(&host->finish_task, au1xmmc_tasklet_finish);
+	INIT_WORK(&host->finish_bh_work, au1xmmc_finish_bh_work);
 
 	if (has_dbdma()) {
 		ret = au1xmmc_dbdma_init(host);
@@ -1091,8 +1092,8 @@ out5:
 	if (host->flags & HOST_F_DBDMA)
 		au1xmmc_dbdma_shutdown(host);
 
-	tasklet_kill(&host->data_task);
-	tasklet_kill(&host->finish_task);
+	cancel_work_sync(&host->data_bh_work);
+	cancel_work_sync(&host->finish_bh_work);
 
 	if (host->platdata && host->platdata->cd_setup &&
 	    !(mmc->caps & MMC_CAP_NEEDS_POLL))
@@ -1135,8 +1136,8 @@ static void au1xmmc_remove(struct platform_device *pdev)
 		__raw_writel(0, HOST_CONFIG2(host));
 		wmb(); /* drain writebuffer */
 
-		tasklet_kill(&host->data_task);
-		tasklet_kill(&host->finish_task);
+		cancel_work_sync(&host->data_bh_work);
+		cancel_work_sync(&host->finish_bh_work);
 
 		if (host->flags & HOST_F_DBDMA)
 			au1xmmc_dbdma_shutdown(host);
diff --git a/drivers/mmc/host/cb710-mmc.c b/drivers/mmc/host/cb710-mmc.c
index 0aec33b88bef..902f7f20abaa 100644
--- a/drivers/mmc/host/cb710-mmc.c
+++ b/drivers/mmc/host/cb710-mmc.c
@@ -493,7 +493,7 @@ static void cb710_mmc_request(struct mmc_host *mmc, struct mmc_request *mrq)
 	if (!cb710_mmc_command(mmc, mrq->cmd) && mrq->stop)
 		cb710_mmc_command(mmc, mrq->stop);
 
-	tasklet_schedule(&reader->finish_req_tasklet);
+	queue_work(system_bh_wq, &reader->finish_req_bh_work);
 }
 
 static int cb710_mmc_powerup(struct cb710_slot *slot)
@@ -646,10 +646,10 @@ static int cb710_mmc_irq_handler(struct cb710_slot *slot)
 	return 1;
 }
 
-static void cb710_mmc_finish_request_tasklet(struct tasklet_struct *t)
+static void cb710_mmc_finish_request_bh_work(struct work_struct *t)
 {
-	struct cb710_mmc_reader *reader = from_tasklet(reader, t,
-						       finish_req_tasklet);
+	struct cb710_mmc_reader *reader = from_work(reader, t,
+						       finish_req_bh_work);
 	struct mmc_request *mrq = reader->mrq;
 
 	reader->mrq = NULL;
@@ -718,8 +718,8 @@ static int cb710_mmc_init(struct platform_device *pdev)
 
 	reader = mmc_priv(mmc);
 
-	tasklet_setup(&reader->finish_req_tasklet,
-		      cb710_mmc_finish_request_tasklet);
+	INIT_WORK(&reader->finish_req_bh_work,
+			cb710_mmc_finish_request_bh_work);
 	spin_lock_init(&reader->irq_lock);
 	cb710_dump_regs(chip, CB710_DUMP_REGS_MMC);
 
@@ -763,7 +763,7 @@ static void cb710_mmc_exit(struct platform_device *pdev)
 	cb710_write_port_32(slot, CB710_MMC_CONFIG_PORT, 0);
 	cb710_write_port_16(slot, CB710_MMC_CONFIGB_PORT, 0);
 
-	tasklet_kill(&reader->finish_req_tasklet);
+	cancel_work_sync(&reader->finish_req_bh_work);
 
 	mmc_free_host(mmc);
 }
diff --git a/drivers/mmc/host/cb710-mmc.h b/drivers/mmc/host/cb710-mmc.h
index 5e053077dbed..59abaccaad10 100644
--- a/drivers/mmc/host/cb710-mmc.h
+++ b/drivers/mmc/host/cb710-mmc.h
@@ -8,10 +8,11 @@
 #define LINUX_CB710_MMC_H
 
 #include <linux/cb710.h>
+#include <linux/workqueue.h>
 
 /* per-MMC-reader structure */
 struct cb710_mmc_reader {
-	struct tasklet_struct finish_req_tasklet;
+	struct work_struct finish_req_bh_work;
 	struct mmc_request *mrq;
 	spinlock_t irq_lock;
 	unsigned char last_power_mode;
diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
index 8e2d676b9239..7195de2cde44 100644
--- a/drivers/mmc/host/dw_mmc.c
+++ b/drivers/mmc/host/dw_mmc.c
@@ -493,7 +493,7 @@ static void dw_mci_dmac_complete_dma(void *arg)
 	 */
 	if (data) {
 		set_bit(EVENT_XFER_COMPLETE, &host->pending_events);
-		tasklet_schedule(&host->tasklet);
+		queue_work(system_bh_wq, &host->bh_work);
 	}
 }
 
@@ -1834,7 +1834,7 @@ static enum hrtimer_restart dw_mci_fault_timer(struct hrtimer *t)
 	if (!host->data_status) {
 		host->data_status = SDMMC_INT_DCRC;
 		set_bit(EVENT_DATA_ERROR, &host->pending_events);
-		tasklet_schedule(&host->tasklet);
+		queue_work(system_bh_wq, &host->bh_work);
 	}
 
 	spin_unlock_irqrestore(&host->irq_lock, flags);
@@ -2056,9 +2056,9 @@ static bool dw_mci_clear_pending_data_complete(struct dw_mci *host)
 	return true;
 }
 
-static void dw_mci_tasklet_func(struct tasklet_struct *t)
+static void dw_mci_work_func(struct work_struct *t)
 {
-	struct dw_mci *host = from_tasklet(host, t, tasklet);
+	struct dw_mci *host = from_work(host, t, bh_work);
 	struct mmc_data	*data;
 	struct mmc_command *cmd;
 	struct mmc_request *mrq;
@@ -2113,7 +2113,7 @@ static void dw_mci_tasklet_func(struct tasklet_struct *t)
 				 * will waste a bit of time (we already know
 				 * the command was bad), it can't cause any
 				 * errors since it's possible it would have
-				 * taken place anyway if this tasklet got
+				 * taken place anyway if this bh work got
 				 * delayed. Allowing the transfer to take place
 				 * avoids races and keeps things simple.
 				 */
@@ -2706,7 +2706,7 @@ static void dw_mci_cmd_interrupt(struct dw_mci *host, u32 status)
 	smp_wmb(); /* drain writebuffer */
 
 	set_bit(EVENT_CMD_COMPLETE, &host->pending_events);
-	tasklet_schedule(&host->tasklet);
+	queue_work(system_bh_wq, &host->bh_work);
 
 	dw_mci_start_fault_timer(host);
 }
@@ -2774,7 +2774,7 @@ static irqreturn_t dw_mci_interrupt(int irq, void *dev_id)
 				set_bit(EVENT_DATA_COMPLETE,
 					&host->pending_events);
 
-			tasklet_schedule(&host->tasklet);
+			queue_work(system_bh_wq, &host->bh_work);
 
 			spin_unlock(&host->irq_lock);
 		}
@@ -2793,7 +2793,7 @@ static irqreturn_t dw_mci_interrupt(int irq, void *dev_id)
 					dw_mci_read_data_pio(host, true);
 			}
 			set_bit(EVENT_DATA_COMPLETE, &host->pending_events);
-			tasklet_schedule(&host->tasklet);
+			queue_work(system_bh_wq, &host->bh_work);
 
 			spin_unlock(&host->irq_lock);
 		}
@@ -3098,7 +3098,7 @@ static void dw_mci_cmd11_timer(struct timer_list *t)
 
 	host->cmd_status = SDMMC_INT_RTO;
 	set_bit(EVENT_CMD_COMPLETE, &host->pending_events);
-	tasklet_schedule(&host->tasklet);
+	queue_work(system_bh_wq, &host->bh_work);
 }
 
 static void dw_mci_cto_timer(struct timer_list *t)
@@ -3144,7 +3144,7 @@ static void dw_mci_cto_timer(struct timer_list *t)
 		 */
 		host->cmd_status = SDMMC_INT_RTO;
 		set_bit(EVENT_CMD_COMPLETE, &host->pending_events);
-		tasklet_schedule(&host->tasklet);
+		queue_work(system_bh_wq, &host->bh_work);
 		break;
 	default:
 		dev_warn(host->dev, "Unexpected command timeout, state %d\n",
@@ -3195,7 +3195,7 @@ static void dw_mci_dto_timer(struct timer_list *t)
 		host->data_status = SDMMC_INT_DRTO;
 		set_bit(EVENT_DATA_ERROR, &host->pending_events);
 		set_bit(EVENT_DATA_COMPLETE, &host->pending_events);
-		tasklet_schedule(&host->tasklet);
+		queue_work(system_bh_wq, &host->bh_work);
 		break;
 	default:
 		dev_warn(host->dev, "Unexpected data timeout, state %d\n",
@@ -3435,7 +3435,7 @@ int dw_mci_probe(struct dw_mci *host)
 	else
 		host->fifo_reg = host->regs + DATA_240A_OFFSET;
 
-	tasklet_setup(&host->tasklet, dw_mci_tasklet_func);
+	INIT_WORK(&host->bh_work, dw_mci_work_func);
 	ret = devm_request_irq(host->dev, host->irq, dw_mci_interrupt,
 			       host->irq_flags, "dw-mci", host);
 	if (ret)
diff --git a/drivers/mmc/host/dw_mmc.h b/drivers/mmc/host/dw_mmc.h
index 4ed81f94f7ca..b504f7ae513a 100644
--- a/drivers/mmc/host/dw_mmc.h
+++ b/drivers/mmc/host/dw_mmc.h
@@ -17,6 +17,7 @@
 #include <linux/fault-inject.h>
 #include <linux/hrtimer.h>
 #include <linux/interrupt.h>
+#include <linux/workqueue.h>
 
 enum dw_mci_state {
 	STATE_IDLE = 0,
@@ -89,12 +90,12 @@ struct dw_mci_dma_slave {
  * @stop_cmdr: Value to be loaded into CMDR when the stop command is
  *	to be sent.
  * @dir_status: Direction of current transfer.
- * @tasklet: Tasklet running the request state machine.
+ * @bh_work: Work running the request state machine.
  * @pending_events: Bitmask of events flagged by the interrupt handler
- *	to be processed by the tasklet.
+ *	to be processed by bh work.
  * @completed_events: Bitmask of events which the state machine has
  *	processed.
- * @state: Tasklet state.
+ * @state: BH work state.
  * @queue: List of slots waiting for access to the controller.
  * @bus_hz: The rate of @mck in Hz. This forms the basis for MMC bus
  *	rate and timeout calculations.
@@ -194,7 +195,7 @@ struct dw_mci {
 	u32			data_status;
 	u32			stop_cmdr;
 	u32			dir_status;
-	struct tasklet_struct	tasklet;
+	struct work_struct	bh_work;
 	unsigned long		pending_events;
 	unsigned long		completed_events;
 	enum dw_mci_state	state;
diff --git a/drivers/mmc/host/omap.c b/drivers/mmc/host/omap.c
index a8ee0df47148..335350a4e99a 100644
--- a/drivers/mmc/host/omap.c
+++ b/drivers/mmc/host/omap.c
@@ -28,6 +28,7 @@
 #include <linux/slab.h>
 #include <linux/gpio/consumer.h>
 #include <linux/platform_data/mmc-omap.h>
+#include <linux/workqueue.h>
 
 
 #define	OMAP_MMC_REG_CMD	0x00
@@ -105,7 +106,7 @@ struct mmc_omap_slot {
 	u16			power_mode;
 	unsigned int		fclk_freq;
 
-	struct tasklet_struct	cover_tasklet;
+	struct work_struct	cover_bh_work;
 	struct timer_list       cover_timer;
 	unsigned		cover_open;
 
@@ -873,18 +874,18 @@ void omap_mmc_notify_cover_event(struct device *dev, int num, int is_closed)
 		sysfs_notify(&slot->mmc->class_dev.kobj, NULL, "cover_switch");
 	}
 
-	tasklet_hi_schedule(&slot->cover_tasklet);
+	queue_work(system_bh_highpri_wq, &slot->cover_bh_work);
 }
 
 static void mmc_omap_cover_timer(struct timer_list *t)
 {
 	struct mmc_omap_slot *slot = from_timer(slot, t, cover_timer);
-	tasklet_schedule(&slot->cover_tasklet);
+	queue_work(system_bh_wq, &slot->cover_bh_work);
 }
 
-static void mmc_omap_cover_handler(struct tasklet_struct *t)
+static void mmc_omap_cover_bh_handler(struct work_struct *t)
 {
-	struct mmc_omap_slot *slot = from_tasklet(slot, t, cover_tasklet);
+	struct mmc_omap_slot *slot = from_work(slot, t, cover_bh_work);
 	int cover_open = mmc_omap_cover_is_open(slot);
 
 	mmc_detect_change(slot->mmc, 0);
@@ -1314,7 +1315,7 @@ static int mmc_omap_new_slot(struct mmc_omap_host *host, int id)
 
 	if (slot->pdata->get_cover_state != NULL) {
 		timer_setup(&slot->cover_timer, mmc_omap_cover_timer, 0);
-		tasklet_setup(&slot->cover_tasklet, mmc_omap_cover_handler);
+		INIT_WORK(&slot->cover_bh_work, mmc_omap_cover_bh_handler);
 	}
 
 	r = mmc_add_host(mmc);
@@ -1333,7 +1334,7 @@ static int mmc_omap_new_slot(struct mmc_omap_host *host, int id)
 					&dev_attr_cover_switch);
 		if (r < 0)
 			goto err_remove_slot_name;
-		tasklet_schedule(&slot->cover_tasklet);
+		queue_work(system_bh_wq, &slot->cover_bh_work);
 	}
 
 	return 0;
@@ -1356,7 +1357,7 @@ static void mmc_omap_remove_slot(struct mmc_omap_slot *slot)
 	if (slot->pdata->get_cover_state != NULL)
 		device_remove_file(&mmc->class_dev, &dev_attr_cover_switch);
 
-	tasklet_kill(&slot->cover_tasklet);
+	cancel_work_sync(&slot->cover_bh_work);
 	del_timer_sync(&slot->cover_timer);
 	flush_workqueue(slot->host->mmc_omap_wq);
 
diff --git a/drivers/mmc/host/sdhci-bcm-kona.c b/drivers/mmc/host/sdhci-bcm-kona.c
index cb9152c6a65d..e067c7f5c537 100644
--- a/drivers/mmc/host/sdhci-bcm-kona.c
+++ b/drivers/mmc/host/sdhci-bcm-kona.c
@@ -107,7 +107,7 @@ static void sdhci_bcm_kona_sd_init(struct sdhci_host *host)
  * Software emulation of the SD card insertion/removal. Set insert=1 for insert
  * and insert=0 for removal. The card detection is done by GPIO. For Broadcom
  * IP to function properly the bit 0 of CORESTAT register needs to be set/reset
- * to generate the CD IRQ handled in sdhci.c which schedules card_tasklet.
+* to generate the CD IRQ handled in sdhci.c
  */
 static int sdhci_bcm_kona_sd_card_emulate(struct sdhci_host *host, int insert)
 {
diff --git a/drivers/mmc/host/tifm_sd.c b/drivers/mmc/host/tifm_sd.c
index b5a2f2f25ad9..aea14bf3e2e8 100644
--- a/drivers/mmc/host/tifm_sd.c
+++ b/drivers/mmc/host/tifm_sd.c
@@ -13,6 +13,7 @@
 #include <linux/highmem.h>
 #include <linux/scatterlist.h>
 #include <linux/module.h>
+#include <linux/workqueue.h>
 #include <asm/io.h>
 
 #define DRIVER_NAME "tifm_sd"
@@ -97,7 +98,7 @@ struct tifm_sd {
 	unsigned int          clk_div;
 	unsigned long         timeout_jiffies;
 
-	struct tasklet_struct finish_tasklet;
+	struct work_struct    finish_bh_work;
 	struct timer_list     timer;
 	struct mmc_request    *req;
 
@@ -463,7 +464,7 @@ static void tifm_sd_check_status(struct tifm_sd *host)
 		}
 	}
 finish_request:
-	tasklet_schedule(&host->finish_tasklet);
+	queue_work(system_bh_wq, &host->finish_bh_work);
 }
 
 /* Called from interrupt handler */
@@ -723,9 +724,9 @@ err_out:
 	mmc_request_done(mmc, mrq);
 }
 
-static void tifm_sd_end_cmd(struct tasklet_struct *t)
+static void tifm_sd_end_cmd(struct work_struct *t)
 {
-	struct tifm_sd *host = from_tasklet(host, t, finish_tasklet);
+	struct tifm_sd *host = from_work(host, t, finish_bh_work);
 	struct tifm_dev *sock = host->dev;
 	struct mmc_host *mmc = tifm_get_drvdata(sock);
 	struct mmc_request *mrq;
@@ -960,7 +961,7 @@ static int tifm_sd_probe(struct tifm_dev *sock)
 	 */
 	mmc->max_busy_timeout = TIFM_MMCSD_REQ_TIMEOUT_MS;
 
-	tasklet_setup(&host->finish_tasklet, tifm_sd_end_cmd);
+	INIT_WORK(&host->finish_bh_work, tifm_sd_end_cmd);
 	timer_setup(&host->timer, tifm_sd_abort, 0);
 
 	mmc->ops = &tifm_sd_ops;
@@ -999,7 +1000,7 @@ static void tifm_sd_remove(struct tifm_dev *sock)
 	writel(0, sock->addr + SOCK_MMCSD_INT_ENABLE);
 	spin_unlock_irqrestore(&sock->lock, flags);
 
-	tasklet_kill(&host->finish_tasklet);
+	cancel_work_sync(&host->finish_bh_work);
 
 	spin_lock_irqsave(&sock->lock, flags);
 	if (host->req) {
@@ -1009,7 +1010,7 @@ static void tifm_sd_remove(struct tifm_dev *sock)
 		host->req->cmd->error = -ENOMEDIUM;
 		if (host->req->stop)
 			host->req->stop->error = -ENOMEDIUM;
-		tasklet_schedule(&host->finish_tasklet);
+		queue_work(system_bh_wq, &host->finish_bh_work);
 	}
 	spin_unlock_irqrestore(&sock->lock, flags);
 	mmc_remove_host(mmc);
diff --git a/drivers/mmc/host/uniphier-sd.c b/drivers/mmc/host/uniphier-sd.c
index 1404989e6151..417fd13efdfd 100644
--- a/drivers/mmc/host/uniphier-sd.c
+++ b/drivers/mmc/host/uniphier-sd.c
@@ -90,9 +90,9 @@ static void uniphier_sd_dma_endisable(struct tmio_mmc_host *host, int enable)
 }
 
 /* external DMA engine */
-static void uniphier_sd_external_dma_issue(struct tasklet_struct *t)
+static void uniphier_sd_external_dma_issue(struct work_struct *t)
 {
-	struct tmio_mmc_host *host = from_tasklet(host, t, dma_issue);
+	struct tmio_mmc_host *host = from_work(host, t, dma_issue);
 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
 
 	uniphier_sd_dma_endisable(host, 1);
@@ -199,7 +199,7 @@ static void uniphier_sd_external_dma_request(struct tmio_mmc_host *host,
 	host->chan_rx = chan;
 	host->chan_tx = chan;
 
-	tasklet_setup(&host->dma_issue, uniphier_sd_external_dma_issue);
+	INIT_WORK(&host->dma_issue, uniphier_sd_external_dma_issue);
 }
 
 static void uniphier_sd_external_dma_release(struct tmio_mmc_host *host)
@@ -236,9 +236,9 @@ static const struct tmio_mmc_dma_ops uniphier_sd_external_dma_ops = {
 	.dataend = uniphier_sd_external_dma_dataend,
 };
 
-static void uniphier_sd_internal_dma_issue(struct tasklet_struct *t)
+static void uniphier_sd_internal_dma_issue(struct work_struct *t)
 {
-	struct tmio_mmc_host *host = from_tasklet(host, t, dma_issue);
+	struct tmio_mmc_host *host = from_work(host, t, dma_issue);
 	unsigned long flags;
 
 	spin_lock_irqsave(&host->lock, flags);
@@ -317,7 +317,7 @@ static void uniphier_sd_internal_dma_request(struct tmio_mmc_host *host,
 
 	host->chan_tx = (void *)0xdeadbeaf;
 
-	tasklet_setup(&host->dma_issue, uniphier_sd_internal_dma_issue);
+	INIT_WORK(&host->dma_issue, uniphier_sd_internal_dma_issue);
 }
 
 static void uniphier_sd_internal_dma_release(struct tmio_mmc_host *host)
diff --git a/drivers/mmc/host/via-sdmmc.c b/drivers/mmc/host/via-sdmmc.c
index ba6044b16e07..f77457105ec3 100644
--- a/drivers/mmc/host/via-sdmmc.c
+++ b/drivers/mmc/host/via-sdmmc.c
@@ -12,6 +12,7 @@
 #include <linux/interrupt.h>
 
 #include <linux/mmc/host.h>
+#include <linux/workqueue.h>
 
 #define DRV_NAME	"via_sdmmc"
 
@@ -307,7 +308,7 @@ struct via_crdr_mmc_host {
 	struct sdhcreg pm_sdhc_reg;
 
 	struct work_struct carddet_work;
-	struct tasklet_struct finish_tasklet;
+	struct work_struct finish_bh_work;
 
 	struct timer_list timer;
 	spinlock_t lock;
@@ -643,7 +644,7 @@ static void via_sdc_finish_data(struct via_crdr_mmc_host *host)
 	if (data->stop)
 		via_sdc_send_command(host, data->stop);
 	else
-		tasklet_schedule(&host->finish_tasklet);
+		queue_work(system_bh_wq, &host->finish_bh_work);
 }
 
 static void via_sdc_finish_command(struct via_crdr_mmc_host *host)
@@ -653,7 +654,7 @@ static void via_sdc_finish_command(struct via_crdr_mmc_host *host)
 	host->cmd->error = 0;
 
 	if (!host->cmd->data)
-		tasklet_schedule(&host->finish_tasklet);
+		queue_work(system_bh_wq, &host->finish_bh_work);
 
 	host->cmd = NULL;
 }
@@ -682,7 +683,7 @@ static void via_sdc_request(struct mmc_host *mmc, struct mmc_request *mrq)
 	status = readw(host->sdhc_mmiobase + VIA_CRDR_SDSTATUS);
 	if (!(status & VIA_CRDR_SDSTS_SLOTG) || host->reject) {
 		host->mrq->cmd->error = -ENOMEDIUM;
-		tasklet_schedule(&host->finish_tasklet);
+		queue_work(system_bh_wq, &host->finish_bh_work);
 	} else {
 		via_sdc_send_command(host, mrq->cmd);
 	}
@@ -848,7 +849,7 @@ static void via_sdc_cmd_isr(struct via_crdr_mmc_host *host, u16 intmask)
 		host->cmd->error = -EILSEQ;
 
 	if (host->cmd->error)
-		tasklet_schedule(&host->finish_tasklet);
+		queue_work(system_bh_wq, &host->finish_bh_work);
 	else if (intmask & VIA_CRDR_SDSTS_CRD)
 		via_sdc_finish_command(host);
 }
@@ -955,16 +956,16 @@ static void via_sdc_timeout(struct timer_list *t)
 				sdhost->cmd->error = -ETIMEDOUT;
 			else
 				sdhost->mrq->cmd->error = -ETIMEDOUT;
-			tasklet_schedule(&sdhost->finish_tasklet);
+			queue_work(system_bh_wq, &sdhost->finish_bh_work);
 		}
 	}
 
 	spin_unlock_irqrestore(&sdhost->lock, flags);
 }
 
-static void via_sdc_tasklet_finish(struct tasklet_struct *t)
+static void via_sdc_finish_bh_work(struct work_struct *t)
 {
-	struct via_crdr_mmc_host *host = from_tasklet(host, t, finish_tasklet);
+	struct via_crdr_mmc_host *host = from_work(host, t, finish_bh_work);
 	unsigned long flags;
 	struct mmc_request *mrq;
 
@@ -1005,7 +1006,7 @@ static void via_sdc_card_detect(struct work_struct *work)
 			pr_err("%s: Card removed during transfer!\n",
 			       mmc_hostname(host->mmc));
 			host->mrq->cmd->error = -ENOMEDIUM;
-			tasklet_schedule(&host->finish_tasklet);
+			queue_work(system_bh_wq, &host->finish_bh_work);
 		}
 
 		spin_unlock_irqrestore(&host->lock, flags);
@@ -1051,7 +1052,7 @@ static void via_init_mmc_host(struct via_crdr_mmc_host *host)
 
 	INIT_WORK(&host->carddet_work, via_sdc_card_detect);
 
-	tasklet_setup(&host->finish_tasklet, via_sdc_tasklet_finish);
+	INIT_WORK(&host->finish_bh_work, via_sdc_finish_bh_work);
 
 	addrbase = host->sdhc_mmiobase;
 	writel(0x0, addrbase + VIA_CRDR_SDINTMASK);
@@ -1193,7 +1194,7 @@ static void via_sd_remove(struct pci_dev *pcidev)
 		sdhost->mrq->cmd->error = -ENOMEDIUM;
 		if (sdhost->mrq->stop)
 			sdhost->mrq->stop->error = -ENOMEDIUM;
-		tasklet_schedule(&sdhost->finish_tasklet);
+		queue_work(system_bh_wq, &sdhost->finish_bh_work);
 	}
 	spin_unlock_irqrestore(&sdhost->lock, flags);
 
@@ -1203,7 +1204,7 @@ static void via_sd_remove(struct pci_dev *pcidev)
 
 	del_timer_sync(&sdhost->timer);
 
-	tasklet_kill(&sdhost->finish_tasklet);
+	cancel_work_sync(&sdhost->finish_bh_work);
 
 	/* switch off power */
 	gatt = readb(sdhost->pcictrl_mmiobase + VIA_CRDR_PCICLKGATT);
diff --git a/drivers/mmc/host/wbsd.c b/drivers/mmc/host/wbsd.c
index f0562f712d98..6e20405d0430 100644
--- a/drivers/mmc/host/wbsd.c
+++ b/drivers/mmc/host/wbsd.c
@@ -459,7 +459,7 @@ static void wbsd_empty_fifo(struct wbsd_host *host)
 	 * FIFO threshold interrupts properly.
 	 */
 	if ((data->blocks * data->blksz - data->bytes_xfered) < 16)
-		tasklet_schedule(&host->fifo_tasklet);
+		queue_work(system_bh_wq, &host->fifo_bh_work);
 }
 
 static void wbsd_fill_fifo(struct wbsd_host *host)
@@ -524,7 +524,7 @@ static void wbsd_fill_fifo(struct wbsd_host *host)
 	 * 'FIFO empty' under certain conditions. So we
 	 * need to be a bit more pro-active.
 	 */
-	tasklet_schedule(&host->fifo_tasklet);
+	queue_work(system_bh_wq, &host->fifo_bh_work);
 }
 
 static void wbsd_prepare_data(struct wbsd_host *host, struct mmc_data *data)
@@ -746,7 +746,7 @@ static void wbsd_request(struct mmc_host *mmc, struct mmc_request *mrq)
 	struct mmc_command *cmd;
 
 	/*
-	 * Disable tasklets to avoid a deadlock.
+	 * Disable bh works to avoid a deadlock.
 	 */
 	spin_lock_bh(&host->lock);
 
@@ -821,7 +821,7 @@ static void wbsd_request(struct mmc_host *mmc, struct mmc_request *mrq)
 		 * Dirty fix for hardware bug.
 		 */
 		if (host->dma == -1)
-			tasklet_schedule(&host->fifo_tasklet);
+			queue_work(system_bh_wq, &host->fifo_bh_work);
 
 		spin_unlock_bh(&host->lock);
 
@@ -961,13 +961,13 @@ static void wbsd_reset_ignore(struct timer_list *t)
 	 * Card status might have changed during the
 	 * blackout.
 	 */
-	tasklet_schedule(&host->card_tasklet);
+	queue_work(system_bh_wq, &host->card_bh_work);
 
 	spin_unlock_bh(&host->lock);
 }
 
 /*
- * Tasklets
+ * BH Works
  */
 
 static inline struct mmc_data *wbsd_get_data(struct wbsd_host *host)
@@ -987,9 +987,9 @@ static inline struct mmc_data *wbsd_get_data(struct wbsd_host *host)
 	return host->mrq->cmd->data;
 }
 
-static void wbsd_tasklet_card(struct tasklet_struct *t)
+static void wbsd_card_bh_work(struct work_struct *t)
 {
-	struct wbsd_host *host = from_tasklet(host, t, card_tasklet);
+	struct wbsd_host *host = from_work(host, t, card_bh_work);
 	u8 csr;
 	int delay = -1;
 
@@ -1020,7 +1020,7 @@ static void wbsd_tasklet_card(struct tasklet_struct *t)
 			wbsd_reset(host);
 
 			host->mrq->cmd->error = -ENOMEDIUM;
-			tasklet_schedule(&host->finish_tasklet);
+			queue_work(system_bh_wq, &host->finish_bh_work);
 		}
 
 		delay = 0;
@@ -1036,9 +1036,9 @@ static void wbsd_tasklet_card(struct tasklet_struct *t)
 		mmc_detect_change(host->mmc, msecs_to_jiffies(delay));
 }
 
-static void wbsd_tasklet_fifo(struct tasklet_struct *t)
+static void wbsd_fifo_bh_work(struct work_struct *t)
 {
-	struct wbsd_host *host = from_tasklet(host, t, fifo_tasklet);
+	struct wbsd_host *host = from_work(host, t, fifo_bh_work);
 	struct mmc_data *data;
 
 	spin_lock(&host->lock);
@@ -1060,16 +1060,16 @@ static void wbsd_tasklet_fifo(struct tasklet_struct *t)
 	 */
 	if (host->num_sg == 0) {
 		wbsd_write_index(host, WBSD_IDX_FIFOEN, 0);
-		tasklet_schedule(&host->finish_tasklet);
+		queue_work(system_bh_wq, &host->finish_bh_work);
 	}
 
 end:
 	spin_unlock(&host->lock);
 }
 
-static void wbsd_tasklet_crc(struct tasklet_struct *t)
+static void wbsd_crc_bh_work(struct work_struct *t)
 {
-	struct wbsd_host *host = from_tasklet(host, t, crc_tasklet);
+	struct wbsd_host *host = from_work(host, t, crc_bh_work);
 	struct mmc_data *data;
 
 	spin_lock(&host->lock);
@@ -1085,15 +1085,15 @@ static void wbsd_tasklet_crc(struct tasklet_struct *t)
 
 	data->error = -EILSEQ;
 
-	tasklet_schedule(&host->finish_tasklet);
+	queue_work(system_bh_wq, &host->finish_bh_work);
 
 end:
 	spin_unlock(&host->lock);
 }
 
-static void wbsd_tasklet_timeout(struct tasklet_struct *t)
+static void wbsd_timeout_bh_work(struct work_struct *t)
 {
-	struct wbsd_host *host = from_tasklet(host, t, timeout_tasklet);
+	struct wbsd_host *host = from_work(host, t, timeout_bh_work);
 	struct mmc_data *data;
 
 	spin_lock(&host->lock);
@@ -1109,15 +1109,15 @@ static void wbsd_tasklet_timeout(struct tasklet_struct *t)
 
 	data->error = -ETIMEDOUT;
 
-	tasklet_schedule(&host->finish_tasklet);
+	queue_work(system_bh_wq, &host->finish_bh_work);
 
 end:
 	spin_unlock(&host->lock);
 }
 
-static void wbsd_tasklet_finish(struct tasklet_struct *t)
+static void wbsd_finish_bh_work(struct work_struct *t)
 {
-	struct wbsd_host *host = from_tasklet(host, t, finish_tasklet);
+	struct wbsd_host *host = from_work(host, t, finish_bh_work);
 	struct mmc_data *data;
 
 	spin_lock(&host->lock);
@@ -1156,18 +1156,18 @@ static irqreturn_t wbsd_irq(int irq, void *dev_id)
 	host->isr |= isr;
 
 	/*
-	 * Schedule tasklets as needed.
+	 * Schedule bh work as needed.
 	 */
 	if (isr & WBSD_INT_CARD)
-		tasklet_schedule(&host->card_tasklet);
+		queue_work(system_bh_wq, &host->card_bh_work);
 	if (isr & WBSD_INT_FIFO_THRE)
-		tasklet_schedule(&host->fifo_tasklet);
+		queue_work(system_bh_wq, &host->fifo_bh_work);
 	if (isr & WBSD_INT_CRC)
-		tasklet_hi_schedule(&host->crc_tasklet);
+		queue_work(system_bh_highpri_wq, &host->crc_bh_work);
 	if (isr & WBSD_INT_TIMEOUT)
-		tasklet_hi_schedule(&host->timeout_tasklet);
+		queue_work(system_bh_highpri_wq, &host->timeout_bh_work);
 	if (isr & WBSD_INT_TC)
-		tasklet_schedule(&host->finish_tasklet);
+		queue_work(system_bh_wq, &host->finish_bh_work);
 
 	return IRQ_HANDLED;
 }
@@ -1443,13 +1443,13 @@ static int wbsd_request_irq(struct wbsd_host *host, int irq)
 	int ret;
 
 	/*
-	 * Set up tasklets. Must be done before requesting interrupt.
+	 * Set up bh works. Must be done before requesting interrupt.
 	 */
-	tasklet_setup(&host->card_tasklet, wbsd_tasklet_card);
-	tasklet_setup(&host->fifo_tasklet, wbsd_tasklet_fifo);
-	tasklet_setup(&host->crc_tasklet, wbsd_tasklet_crc);
-	tasklet_setup(&host->timeout_tasklet, wbsd_tasklet_timeout);
-	tasklet_setup(&host->finish_tasklet, wbsd_tasklet_finish);
+	INIT_WORK(&host->card_bh_work, wbsd_card_bh_work);
+	INIT_WORK(&host->fifo_bh_work, wbsd_fifo_bh_work);
+	INIT_WORK(&host->crc_bh_work, wbsd_crc_bh_work);
+	INIT_WORK(&host->timeout_bh_work, wbsd_timeout_bh_work);
+	INIT_WORK(&host->finish_bh_work, wbsd_finish_bh_work);
 
 	/*
 	 * Allocate interrupt.
@@ -1472,11 +1472,11 @@ static void  wbsd_release_irq(struct wbsd_host *host)
 
 	host->irq = 0;
 
-	tasklet_kill(&host->card_tasklet);
-	tasklet_kill(&host->fifo_tasklet);
-	tasklet_kill(&host->crc_tasklet);
-	tasklet_kill(&host->timeout_tasklet);
-	tasklet_kill(&host->finish_tasklet);
+	cancel_work_sync(&host->card_bh_work);
+	cancel_work_sync(&host->fifo_bh_work);
+	cancel_work_sync(&host->crc_bh_work);
+	cancel_work_sync(&host->timeout_bh_work);
+	cancel_work_sync(&host->finish_bh_work);
 }
 
 /*
diff --git a/drivers/mmc/host/wbsd.h b/drivers/mmc/host/wbsd.h
index be30b4d8ce4c..970886831305 100644
--- a/drivers/mmc/host/wbsd.h
+++ b/drivers/mmc/host/wbsd.h
@@ -171,11 +171,11 @@ struct wbsd_host
 	int			irq;		/* Interrupt */
 	int			dma;		/* DMA channel */
 
-	struct tasklet_struct	card_tasklet;	/* Tasklet structures */
-	struct tasklet_struct	fifo_tasklet;
-	struct tasklet_struct	crc_tasklet;
-	struct tasklet_struct	timeout_tasklet;
-	struct tasklet_struct	finish_tasklet;
+	struct work_struct	card_bh_work;	/* Work structures */
+	struct work_struct	fifo_bh_work;
+	struct work_struct	crc_bh_work;
+	struct work_struct	timeout_bh_work;
+	struct work_struct	finish_bh_work;
 
 	struct timer_list	ignore_timer;	/* Ignore detection timer */
 };