media: 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/media/* from tasklet to BH workqueue.

Based on the work done by Tejun Heo <[e-mail]>

Signed-off-by: Allen Pais <[e-mail]>
Signed-off-by: Hans Verkuil <[e-mail]>

drivers/media/pci/bt8xx/bt878.c

···
 		}
 		if (astat & BT878_ARISCI) {
 			bt->finished_block = (stat & BT878_ARISCS) >> 28;
-			if (bt->tasklet.callback)
-				tasklet_schedule(&bt->tasklet);
+			if (bt->bh_work.func)
+				queue_work(system_bh_wq, &bt->bh_work);
 			break;
 		}
 		count++;
···
 	btwrite(0, BT878_AINT_MASK);
 	bt878_num++;
 
-	if (!bt->tasklet.func)
-		tasklet_disable(&bt->tasklet);
+	if (!bt->bh_work.func)
+		disable_work_sync(&bt->bh_work);
 
 	return 0;
 

drivers/media/pci/bt8xx/bt878.h

···
 #include <linux/sched.h>
 #include <linux/spinlock.h>
 #include <linux/mutex.h>
+#include <linux/workqueue.h>
 
 #include "bt848.h"
 #include "bttv.h"
···
 	dma_addr_t risc_dma;
 	u32 risc_pos;
 
-	struct tasklet_struct tasklet;
+	struct work_struct bh_work;
 	int shutdown;
 };
 

drivers/media/pci/bt8xx/dvb-bt8xx.c

···
 
 #define IF_FREQUENCYx6 217    /* 6 * 36.16666666667MHz */
 
-static void dvb_bt8xx_task(struct tasklet_struct *t)
+static void dvb_bt8xx_work(struct work_struct *t)
 {
-	struct bt878 *bt = from_tasklet(bt, t, tasklet);
+	struct bt878 *bt = from_work(bt, t, bh_work);
 	struct dvb_bt8xx_card *card = dev_get_drvdata(&bt->adapter->dev);
 
 	dprintk("%d\n", card->bt->finished_block);
···
 		goto err_disconnect_frontend;
 	}
 
-	tasklet_setup(&card->bt->tasklet, dvb_bt8xx_task);
+	INIT_WORK(&card->bt->bh_work, dvb_bt8xx_work);
 
 	frontend_init(card, type);
 
···
 	dprintk("dvb_bt8xx: unloading card%d\n", card->bttv_nr);
 
 	bt878_stop(card->bt);
-	tasklet_kill(&card->bt->tasklet);
+	cancel_work_sync(&card->bt->bh_work);
 	dvb_net_release(&card->dvbnet);
 	card->demux.dmx.remove_frontend(&card->demux.dmx, &card->fe_mem);
 	card->demux.dmx.remove_frontend(&card->demux.dmx, &card->fe_hw);

drivers/media/pci/ddbridge/ddbridge.h

···
 	spinlock_t             lock; /* lock link access */
 	struct mutex           flash_mutex; /* lock flash access */
 	struct ddb_lnb         lnb;
-	struct tasklet_struct  tasklet;
+	struct work_struct     bh_work;
 	struct ddb_ids         ids;
 
 	spinlock_t             temp_lock; /* lock temp chip access */

drivers/media/pci/mantis/hopper_cards.c

···
 	if (stat & MANTIS_INT_RISCI) {
 		dprintk(MANTIS_DEBUG, 0, "<%s>", label[8]);
 		mantis->busy_block = (stat & MANTIS_INT_RISCSTAT) >> 28;
-		tasklet_schedule(&mantis->tasklet);
+		queue_work(system_bh_wq, &mantis->bh_work);
 	}
 	if (stat & MANTIS_INT_I2CDONE) {
 		dprintk(MANTIS_DEBUG, 0, "<%s>", label[9]);

drivers/media/pci/mantis/mantis_cards.c

···
 	if (stat & MANTIS_INT_RISCI) {
 		dprintk(MANTIS_DEBUG, 0, "<%s>", label[8]);
 		mantis->busy_block = (stat & MANTIS_INT_RISCSTAT) >> 28;
-		tasklet_schedule(&mantis->tasklet);
+		queue_work(system_bh_wq, &mantis->bh_work);
 	}
 	if (stat & MANTIS_INT_I2CDONE) {
 		dprintk(MANTIS_DEBUG, 0, "<%s>", label[9]);

drivers/media/pci/mantis/mantis_common.h

···
 	__le32			*risc_cpu;
 	dma_addr_t		risc_dma;
 
-	struct tasklet_struct	tasklet;
+	struct work_struct	bh_work;
 	spinlock_t		intmask_lock;
 
 	struct i2c_adapter	adapter;

drivers/media/pci/mantis/mantis_dma.c

···
 }
 
 
-void mantis_dma_xfer(struct tasklet_struct *t)
+void mantis_dma_xfer(struct work_struct *t)
 {
-	struct mantis_pci *mantis = from_tasklet(mantis, t, tasklet);
+	struct mantis_pci *mantis = from_work(mantis, t, bh_work);
 	struct mantis_hwconfig *config = mantis->hwconfig;
 
 	while (mantis->last_block != mantis->busy_block) {

drivers/media/pci/mantis/mantis_dma.h

···
 extern int mantis_dma_exit(struct mantis_pci *mantis);
 extern void mantis_dma_start(struct mantis_pci *mantis);
 extern void mantis_dma_stop(struct mantis_pci *mantis);
-extern void mantis_dma_xfer(struct tasklet_struct *t);
+extern void mantis_dma_xfer(struct work_struct *t);
 
 #endif /* __MANTIS_DMA_H */

drivers/media/pci/mantis/mantis_dvb.c

···
 	if (mantis->feeds == 1)	 {
 		dprintk(MANTIS_DEBUG, 1, "mantis start feed & dma");
 		mantis_dma_start(mantis);
-		tasklet_enable(&mantis->tasklet);
+		enable_and_queue_work(system_bh_wq, &mantis->bh_work);
 	}
 
 	return mantis->feeds;
···
 	mantis->feeds--;
 	if (mantis->feeds == 0) {
 		dprintk(MANTIS_DEBUG, 1, "mantis stop feed and dma");
-		tasklet_disable(&mantis->tasklet);
+		disable_work_sync(&mantis->bh_work);
 		mantis_dma_stop(mantis);
 	}
 
···
 	}
 
 	dvb_net_init(&mantis->dvb_adapter, &mantis->dvbnet, &mantis->demux.dmx);
-	tasklet_setup(&mantis->tasklet, mantis_dma_xfer);
-	tasklet_disable(&mantis->tasklet);
+	INIT_WORK(&mantis->bh_work, mantis_dma_xfer);
+	disable_work_sync(&mantis->bh_work);
 	if (mantis->hwconfig) {
 		result = config->frontend_init(mantis, mantis->fe);
 		if (result < 0) {
···
 
 	/* Error conditions ..	*/
 err5:
-	tasklet_kill(&mantis->tasklet);
+	cancel_work_sync(&mantis->bh_work);
 	dvb_net_release(&mantis->dvbnet);
 	if (mantis->fe) {
 		dvb_unregister_frontend(mantis->fe);
···
 		dvb_frontend_detach(mantis->fe);
 	}
 
-	tasklet_kill(&mantis->tasklet);
+	cancel_work_sync(&mantis->bh_work);
 	dvb_net_release(&mantis->dvbnet);
 
 	mantis->demux.dmx.remove_frontend(&mantis->demux.dmx, &mantis->fe_mem);

drivers/media/pci/ngene/ngene-core.c

···
 /* nGene interrupt handler **************************************************/
 /****************************************************************************/
 
-static void event_tasklet(struct tasklet_struct *t)
+static void event_bh_work(struct work_struct *t)
 {
-	struct ngene *dev = from_tasklet(dev, t, event_tasklet);
+	struct ngene *dev = from_work(dev, t, event_bh_work);
 
 	while (dev->EventQueueReadIndex != dev->EventQueueWriteIndex) {
 		struct EVENT_BUFFER Event =
···
 	}
 }
 
-static void demux_tasklet(struct tasklet_struct *t)
+static void demux_bh_work(struct work_struct *t)
 {
-	struct ngene_channel *chan = from_tasklet(chan, t, demux_tasklet);
+	struct ngene_channel *chan = from_work(chan, t, demux_bh_work);
 	struct device *pdev = &chan->dev->pci_dev->dev;
 	struct SBufferHeader *Cur = chan->nextBuffer;
 
···
 			dev->EventQueueOverflowFlag = 1;
 		}
 		dev->EventBuffer->EventStatus &= ~0x80;
-		tasklet_schedule(&dev->event_tasklet);
+		queue_work(system_bh_wq, &dev->event_bh_work);
 		rc = IRQ_HANDLED;
 	}
 
···
 			     ngeneBuffer.SR.Flags & 0xC0) == 0x80) {
 				dev->channel[i].nextBuffer->
 					ngeneBuffer.SR.Flags |= 0x40;
-				tasklet_schedule(
-					&dev->channel[i].demux_tasklet);
+				queue_work(system_bh_wq,
+					   &dev->channel[i].demux_bh_work);
 				rc = IRQ_HANDLED;
 			}
 		}
···
 	struct device *pdev = &dev->pci_dev->dev;
 	int i;
 
-	tasklet_setup(&dev->event_tasklet, event_tasklet);
+	INIT_WORK(&dev->event_bh_work, event_bh_work);
 
 	memset_io(dev->iomem + 0xc000, 0x00, 0x220);
 	memset_io(dev->iomem + 0xc400, 0x00, 0x100);
···
 	if (chan->running)
 		set_transfer(chan, 0);
 
-	tasklet_kill(&chan->demux_tasklet);
+	cancel_work_sync(&chan->demux_bh_work);
 
 	if (chan->ci_dev) {
 		dvb_unregister_device(chan->ci_dev);
···
 	struct ngene_info *ni = dev->card_info;
 	int io = ni->io_type[nr];
 
-	tasklet_setup(&chan->demux_tasklet, demux_tasklet);
+	INIT_WORK(&chan->demux_bh_work, demux_bh_work);
 	chan->users = 0;
 	chan->type = io;
 	chan->mode = chan->type;	/* for now only one mode */
···
 	struct ngene *dev = pci_get_drvdata(pdev);
 	int i;
 
-	tasklet_kill(&dev->event_tasklet);
+	cancel_work_sync(&dev->event_bh_work);
 	for (i = MAX_STREAM - 1; i >= 0; i--)
 		release_channel(&dev->channel[i]);
 	if (dev->ci.en)

drivers/media/pci/ngene/ngene.h

···
 #include <linux/scatterlist.h>
 
 #include <linux/dvb/frontend.h>
+#include <linux/workqueue.h>
 
 #include <media/dmxdev.h>
 #include <media/dvbdev.h>
···
 	int                   users;
 	struct video_device  *v4l_dev;
 	struct dvb_device    *ci_dev;
-	struct tasklet_struct demux_tasklet;
+	struct work_struct    demux_bh_work;
 
 	struct SBufferHeader *nextBuffer;
 	enum KSSTATE          State;
···
 	struct EVENT_BUFFER   EventQueue[EVENT_QUEUE_SIZE];
 	int                   EventQueueOverflowCount;
 	int                   EventQueueOverflowFlag;
-	struct tasklet_struct event_tasklet;
+	struct work_struct    event_bh_work;
 	struct EVENT_BUFFER  *EventBuffer;
 	int                   EventQueueWriteIndex;
 	int                   EventQueueReadIndex;

drivers/media/pci/smipcie/smipcie-main.c

···
 		(port->_dmaInterruptCH0 | port->_dmaInterruptCH1));
 }
 
-/* tasklet handler: DMA data to dmx.*/
-static void smi_dma_xfer(struct tasklet_struct *t)
+/* BH work handler: DMA data to dmx.*/
+static void smi_dma_xfer(struct work_struct *t)
 {
-	struct smi_port *port = from_tasklet(port, t, tasklet);
+	struct smi_port *port = from_work(port, t, bh_work);
 	struct smi_dev *dev = port->dev;
 	u32 intr_status, finishedData, dmaManagement;
 	u8 dmaChan0State, dmaChan1State;
···
 	}
 
 	smi_port_disableInterrupt(port);
-	tasklet_setup(&port->tasklet, smi_dma_xfer);
-	tasklet_disable(&port->tasklet);
+	INIT_WORK(&port->bh_work, smi_dma_xfer);
+	disable_work_sync(&port->bh_work);
 	port->enable = 1;
 	return 0;
 err:
···
 static void smi_port_exit(struct smi_port *port)
 {
 	smi_port_disableInterrupt(port);
-	tasklet_kill(&port->tasklet);
+	cancel_work_sync(&port->bh_work);
 	smi_port_dma_free(port);
 	port->enable = 0;
 }
···
 		smi_port_disableInterrupt(port);
 		port->_int_status = int_status;
 		smi_port_clearInterrupt(port);
-		tasklet_schedule(&port->tasklet);
+		queue_work(system_bh_wq, &port->bh_work);
 		handled = 1;
 	}
 	return handled;
···
 		smi_port_clearInterrupt(port);
 		smi_port_enableInterrupt(port);
 		smi_write(port->DMA_MANAGEMENT, dmaManagement);
-		tasklet_enable(&port->tasklet);
+		enable_and_queue_work(system_bh_wq, &port->bh_work);
 	}
 	return port->users;
 }
···
 	if (--port->users)
 		return port->users;
 
-	tasklet_disable(&port->tasklet);
+	disable_work_sync(&port->bh_work);
 	smi_port_disableInterrupt(port);
 	smi_clear(port->DMA_MANAGEMENT, 0x30003);
 	return 0;

drivers/media/pci/smipcie/smipcie.h

···
 #include <linux/pci.h>
 #include <linux/dma-mapping.h>
 #include <linux/slab.h>
+#include <linux/workqueue.h>
 #include <media/rc-core.h>
 
 #include <media/demux.h>
···
 	u32 _dmaInterruptCH0;
 	u32 _dmaInterruptCH1;
 	u32 _int_status;
-	struct tasklet_struct tasklet;
+	struct work_struct bh_work;
 	/* dvb */
 	struct dmx_frontend hw_frontend;
 	struct dmx_frontend mem_frontend;

drivers/media/pci/ttpci/budget-av.c

···
 #include <linux/interrupt.h>
 #include <linux/input.h>
 #include <linux/spinlock.h>
+#include <linux/workqueue.h>
 
 #include <media/dvb_ca_en50221.h>
 
···
 	struct video_device vd;
 	int cur_input;
 	int has_saa7113;
-	struct tasklet_struct ciintf_irq_tasklet;
+	struct work_struct ciintf_irq_bh_work;
 	int slot_status;
 	struct dvb_ca_en50221 ca;
 	u8 reinitialise_demod:1;

drivers/media/pci/ttpci/budget-ci.c

···
 #include <linux/slab.h>
 #include <linux/interrupt.h>
 #include <linux/spinlock.h>
+#include <linux/workqueue.h>
 #include <media/rc-core.h>
 
 #include "budget.h"
···
 
 struct budget_ci_ir {
 	struct rc_dev *dev;
-	struct tasklet_struct msp430_irq_tasklet;
+	struct work_struct msp430_irq_bh_work;
 	char name[72]; /* 40 + 32 for (struct saa7146_dev).name */
 	char phys[32];
 	int rc5_device;
···
 
 struct budget_ci {
 	struct budget budget;
-	struct tasklet_struct ciintf_irq_tasklet;
+	struct work_struct ciintf_irq_bh_work;
 	int slot_status;
 	int ci_irq;
 	struct dvb_ca_en50221 ca;
···
 	u8 tuner_pll_address; /* used for philips_tdm1316l configs */
 };
 
-static void msp430_ir_interrupt(struct tasklet_struct *t)
+static void msp430_ir_interrupt(struct work_struct *t)
 {
-	struct budget_ci_ir *ir = from_tasklet(ir, t, msp430_irq_tasklet);
+	struct budget_ci_ir *ir = from_work(ir, t, msp430_irq_bh_work);
 	struct budget_ci *budget_ci = container_of(ir, typeof(*budget_ci), ir);
 	struct rc_dev *dev = budget_ci->ir.dev;
 	u32 command = ttpci_budget_debiread(&budget_ci->budget, DEBINOSWAP, DEBIADDR_IR, 2, 1, 0) >> 8;
···
 
 	budget_ci->ir.dev = dev;
 
-	tasklet_setup(&budget_ci->ir.msp430_irq_tasklet, msp430_ir_interrupt);
+	INIT_WORK(&budget_ci->ir.msp430_irq_bh_work, msp430_ir_interrupt);
 
 	SAA7146_IER_ENABLE(saa, MASK_06);
 	saa7146_setgpio(saa, 3, SAA7146_GPIO_IRQHI);
···
 
 	SAA7146_IER_DISABLE(saa, MASK_06);
 	saa7146_setgpio(saa, 3, SAA7146_GPIO_INPUT);
-	tasklet_kill(&budget_ci->ir.msp430_irq_tasklet);
+	cancel_work_sync(&budget_ci->ir.msp430_irq_bh_work);
 
 	rc_unregister_device(budget_ci->ir.dev);
 }
···
 	return 0;
 }
 
-static void ciintf_interrupt(struct tasklet_struct *t)
+static void ciintf_interrupt(struct work_struct *t)
 {
-	struct budget_ci *budget_ci = from_tasklet(budget_ci, t,
-						   ciintf_irq_tasklet);
+	struct budget_ci *budget_ci = from_work(budget_ci, t,
+						   ciintf_irq_bh_work);
 	struct saa7146_dev *saa = budget_ci->budget.dev;
 	unsigned int flags;
 
···
 
 	// Setup CI slot IRQ
 	if (budget_ci->ci_irq) {
-		tasklet_setup(&budget_ci->ciintf_irq_tasklet, ciintf_interrupt);
+		INIT_WORK(&budget_ci->ciintf_irq_bh_work, ciintf_interrupt);
 		if (budget_ci->slot_status != SLOTSTATUS_NONE)
 			saa7146_setgpio(saa, 0, SAA7146_GPIO_IRQLO);
 		else
···
 	if (budget_ci->ci_irq) {
 		SAA7146_IER_DISABLE(saa, MASK_03);
 		saa7146_setgpio(saa, 0, SAA7146_GPIO_INPUT);
-		tasklet_kill(&budget_ci->ciintf_irq_tasklet);
+		cancel_work_sync(&budget_ci->ciintf_irq_bh_work);
 	}
 
 	// reset interface
···
 	dprintk(8, "dev: %p, budget_ci: %p\n", dev, budget_ci);
 
 	if (*isr & MASK_06)
-		tasklet_schedule(&budget_ci->ir.msp430_irq_tasklet);
+		queue_work(system_bh_wq, &budget_ci->ir.msp430_irq_bh_work);
 
 	if (*isr & MASK_10)
 		ttpci_budget_irq10_handler(dev, isr);
 
 	if ((*isr & MASK_03) && (budget_ci->budget.ci_present) && (budget_ci->ci_irq))
-		tasklet_schedule(&budget_ci->ciintf_irq_tasklet);
+		queue_work(system_bh_wq, &budget_ci->ciintf_irq_bh_work);
 }
 
 static u8 philips_su1278_tt_inittab[] = {

drivers/media/pci/ttpci/budget-core.c

···
 	return ret;
 }
 
-static void vpeirq(struct tasklet_struct *t)
+static void vpeirq(struct work_struct *t)
 {
-	struct budget *budget = from_tasklet(budget, t, vpe_tasklet);
+	struct budget *budget = from_work(budget, t, vpe_bh_work);
 	u8 *mem = (u8 *) (budget->grabbing);
 	u32 olddma = budget->ttbp;
 	u32 newdma = saa7146_read(budget->dev, PCI_VDP3);
···
 	/* upload all */
 	saa7146_write(dev, GPIO_CTRL, 0x000000);
 
-	tasklet_setup(&budget->vpe_tasklet, vpeirq);
+	INIT_WORK(&budget->vpe_bh_work, vpeirq);
 
 	/* frontend power on */
 	if (bi->type != BUDGET_FS_ACTIVY)
···
 
 	budget_unregister(budget);
 
-	tasklet_kill(&budget->vpe_tasklet);
+	cancel_work_sync(&budget->vpe_bh_work);
 
 	saa7146_vfree_destroy_pgtable(dev->pci, budget->grabbing, &budget->pt);
 
···
 	dprintk(8, "dev: %p, budget: %p\n", dev, budget);
 
 	if (*isr & MASK_10)
-		tasklet_schedule(&budget->vpe_tasklet);
+		queue_work(system_bh_wq, &budget->vpe_bh_work);
 }
 EXPORT_SYMBOL_GPL(ttpci_budget_irq10_handler);
 

drivers/media/pci/ttpci/budget.h

···
 
 #include <linux/module.h>
 #include <linux/mutex.h>
+#include <linux/workqueue.h>
 
 #include <media/drv-intf/saa7146.h>
 
···
 	unsigned char *grabbing;
 	struct saa7146_pgtable pt;
 
-	struct tasklet_struct fidb_tasklet;
-	struct tasklet_struct vpe_tasklet;
+	struct work_struct fidb_bh_work;
+	struct work_struct vpe_bh_work;
 
 	struct dmxdev dmxdev;
 	struct dvb_demux demux;

drivers/media/pci/tw5864/tw5864-core.c

···
 		cur_frame->gop_seqno = input->frame_gop_seqno;
 
 		dev->h264_buf_w_index = next_frame_index;
-		tasklet_schedule(&dev->tasklet);
+		queue_work(system_bh_wq, &dev->bh_work);
 
 		cur_frame = next_frame;
 

drivers/media/pci/tw5864/tw5864-video.c

···
  */
 
 #include <linux/module.h>
+#include <linux/workqueue.h>
 #include <media/v4l2-common.h>
 #include <media/v4l2-event.h>
 #include <media/videobuf2-dma-contig.h>
···
 static v4l2_std_id tw5864_get_v4l2_std(enum tw5864_vid_std std);
 static enum tw5864_vid_std tw5864_from_v4l2_std(v4l2_std_id v4l2_std);
 
-static void tw5864_handle_frame_task(struct tasklet_struct *t);
+static void tw5864_handle_frame_work(struct work_struct *t);
 static void tw5864_handle_frame(struct tw5864_h264_frame *frame);
 static void tw5864_frame_interval_set(struct tw5864_input *input);
 
···
 	dev->irqmask |= TW5864_INTR_VLC_DONE | TW5864_INTR_TIMER;
 	tw5864_irqmask_apply(dev);
 
-	tasklet_setup(&dev->tasklet, tw5864_handle_frame_task);
+	INIT_WORK(&dev->bh_work, tw5864_handle_frame_work);
 
 	for (i = 0; i < TW5864_INPUTS; i++) {
 		dev->inputs[i].root = dev;
···
 	for (i = last_input_nr_registered; i >= 0; i--)
 		tw5864_video_input_fini(&dev->inputs[i]);
 
-	tasklet_kill(&dev->tasklet);
+	cancel_work_sync(&dev->bh_work);
 
 free_dma:
 	for (i = last_dma_allocated; i >= 0; i--) {
···
 {
 	int i;
 
-	tasklet_kill(&dev->tasklet);
+	cancel_work_sync(&dev->bh_work);
 
 	for (i = 0; i < TW5864_INPUTS; i++)
 		tw5864_video_input_fini(&dev->inputs[i]);
···
 	return detected;
 }
 
-static void tw5864_handle_frame_task(struct tasklet_struct *t)
+static void tw5864_handle_frame_work(struct work_struct *t)
 {
-	struct tw5864_dev *dev = from_tasklet(dev, t, tasklet);
+	struct tw5864_dev *dev = from_work(dev, t, bh_work);
 	unsigned long flags;
 	int batch_size = H264_BUF_CNT;
 

drivers/media/pci/tw5864/tw5864.h

···
 #include <linux/mutex.h>
 #include <linux/io.h>
 #include <linux/interrupt.h>
+#include <linux/workqueue.h>
 
 #include <media/v4l2-common.h>
 #include <media/v4l2-ioctl.h>
···
 	int nr; /* input number */
 	struct tw5864_dev *root;
 	struct mutex lock; /* used for vidq and vdev */
-	spinlock_t slock; /* used for sync between ISR, tasklet & V4L2 API */
+	spinlock_t slock; /* used for sync between ISR, bh_work & V4L2 API */
 	struct video_device vdev;
 	struct v4l2_ctrl_handler hdl;
 	struct vb2_queue vidq;
···
 
 /* global device status */
 struct tw5864_dev {
-	spinlock_t slock; /* used for sync between ISR, tasklet & V4L2 API */
+	spinlock_t slock; /* used for sync between ISR, bh_work & V4L2 API */
 	struct v4l2_device v4l2_dev;
 	struct tw5864_input inputs[TW5864_INPUTS];
 #define H264_BUF_CNT 4
···
 	int h264_buf_r_index;
 	int h264_buf_w_index;
 
-	struct tasklet_struct tasklet;
+	struct work_struct bh_work;
 
 	int encoder_busy;
 	/* Input number to check next for ready raw picture (in RR fashion) */

drivers/media/platform/intel/pxa_camera.c

···
 #include <linux/videodev2.h>
 
 #include <linux/platform_data/media/camera-pxa.h>
+#include <linux/workqueue.h>
 
 #define PXA_CAM_VERSION "0.0.6"
 #define PXA_CAM_DRV_NAME "pxa27x-camera"
···
 	unsigned int		buf_sequence;
 
 	struct pxa_buffer	*active;
-	struct tasklet_struct	task_eof;
+	struct work_struct	eof_bh_work;
 
 	u32			save_cicr[5];
 };
···
 	clk_disable_unprepare(pcdev->clk);
 }
 
-static void pxa_camera_eof(struct tasklet_struct *t)
+static void pxa_camera_eof_bh_work(struct work_struct *t)
 {
-	struct pxa_camera_dev *pcdev = from_tasklet(pcdev, t, task_eof);
+	struct pxa_camera_dev *pcdev = from_work(pcdev, t, eof_bh_work);
 	unsigned long cifr;
 	struct pxa_buffer *buf;
 
···
 	if (status & CISR_EOF) {
 		cicr0 = __raw_readl(pcdev->base + CICR0) | CICR0_EOFM;
 		__raw_writel(cicr0, pcdev->base + CICR0);
-		tasklet_schedule(&pcdev->task_eof);
+		queue_work(system_bh_wq, &pcdev->eof_bh_work);
 	}
 
 	return IRQ_HANDLED;
···
 		}
 	}
 
-	tasklet_setup(&pcdev->task_eof, pxa_camera_eof);
+	INIT_WORK(&pcdev->eof_bh_work, pxa_camera_eof_bh_work);
 
 	pxa_camera_activate(pcdev);
 
···
 	return 0;
 exit_deactivate:
 	pxa_camera_deactivate(pcdev);
-	tasklet_kill(&pcdev->task_eof);
+	cancel_work_sync(&pcdev->eof_bh_work);
 exit_free_dma:
 	dma_release_channel(pcdev->dma_chans[2]);
 exit_free_dma_u:
···
 	struct pxa_camera_dev *pcdev = platform_get_drvdata(pdev);
 
 	pxa_camera_deactivate(pcdev);
-	tasklet_kill(&pcdev->task_eof);
+	cancel_work_sync(&pcdev->eof_bh_work);
 	dma_release_channel(pcdev->dma_chans[0]);
 	dma_release_channel(pcdev->dma_chans[1]);
 	dma_release_channel(pcdev->dma_chans[2]);

drivers/media/platform/marvell/mcam-core.c

···
 /*
  * Copy data out to user space in the vmalloc case
  */
-static void mcam_frame_tasklet(struct tasklet_struct *t)
+static void mcam_frame_work(struct work_struct *t)
 {
-	struct mcam_camera *cam = from_tasklet(cam, t, s_tasklet);
+	struct mcam_camera *cam = from_work(cam, t, s_bh_work);
 	int i;
 	unsigned long flags;
 	struct mcam_vb_buffer *buf;
···
 
 static void mcam_vmalloc_done(struct mcam_camera *cam, int frame)
 {
-	tasklet_schedule(&cam->s_tasklet);
+	queue_work(system_bh_wq, &cam->s_bh_work);
 }
 
 #else /* MCAM_MODE_VMALLOC */
···
 		break;
 	case B_vmalloc:
 #ifdef MCAM_MODE_VMALLOC
-		tasklet_setup(&cam->s_tasklet, mcam_frame_tasklet);
+		INIT_WORK(&cam->s_bh_work, mcam_frame_work);
 		vq->ops = &mcam_vb2_ops;
 		vq->mem_ops = &vb2_vmalloc_memops;
 		cam->dma_setup = mcam_ctlr_dma_vmalloc;

drivers/media/platform/marvell/mcam-core.h

···
 
 #include <linux/list.h>
 #include <linux/clk-provider.h>
+#include <linux/workqueue.h>
 #include <media/v4l2-common.h>
 #include <media/v4l2-ctrls.h>
 #include <media/v4l2-dev.h>
···
 	unsigned int dma_buf_size;	/* allocated size */
 	void *dma_bufs[MAX_DMA_BUFS];	/* Internal buffer addresses */
 	dma_addr_t dma_handles[MAX_DMA_BUFS]; /* Buffer bus addresses */
-	struct tasklet_struct s_tasklet;
+	struct work_struct s_bh_work;
 #endif
 	unsigned int sequence;		/* Frame sequence number */
 	unsigned int buf_seq[MAX_DMA_BUFS]; /* Sequence for individual bufs */

drivers/media/platform/st/sti/c8sectpfe/c8sectpfe-core.c

···
 
 		/* is this descriptor initialised and TP enabled */
 		if (channel->irec && readl(channel->irec + DMA_PRDS_TPENABLE))
-			tasklet_schedule(&channel->tsklet);
+			queue_work(system_bh_wq, &channel->bh_work);
 	}
 
 	fei->timer.expires = jiffies +	msecs_to_jiffies(POLL_MSECS);
 	add_timer(&fei->timer);
 }
 
-static void channel_swdemux_tsklet(struct tasklet_struct *t)
+static void channel_swdemux_bh_work(struct work_struct *t)
 {
-	struct channel_info *channel = from_tasklet(channel, t, tsklet);
+	struct channel_info *channel = from_work(channel, t, bh_work);
 	struct c8sectpfei *fei;
 	unsigned long wp, rp;
 	int pos, num_packets, n, size;
···
 
 		dev_dbg(fei->dev, "Starting channel=%p\n", channel);
 
-		tasklet_setup(&channel->tsklet, channel_swdemux_tsklet);
+		INIT_WORK(&channel->bh_work, channel_swdemux_bh_work);
 
 		/* Reset the internal inputblock sram pointers */
 		writel(channel->fifo,
···
 		/* disable this channels descriptor */
 		writel(0,  channel->irec + DMA_PRDS_TPENABLE);
 
-		tasklet_disable(&channel->tsklet);
+		disable_work_sync(&channel->bh_work);
 
 		/* now request memdma channel goes idle */
 		idlereq = (1 << channel->tsin_id) | IDLEREQ;
···
 	writel(tsin->back_buffer_busaddr, tsin->irec + DMA_PRDS_BUSWP_TP(0));
 	writel(tsin->back_buffer_busaddr, tsin->irec + DMA_PRDS_BUSRP_TP(0));
 
-	/* initialize tasklet */
-	tasklet_setup(&tsin->tsklet, channel_swdemux_tsklet);
+	/* initialize bh work */
+	INIT_WORK(&tsin->bh_work, channel_swdemux_bh_work);
 
 	return 0;
 

drivers/media/platform/st/sti/c8sectpfe/c8sectpfe-core.h

···
 	unsigned long  fifo;
 
 	struct completion idle_completion;
-	struct tasklet_struct tsklet;
+	struct work_struct bh_work;
 
 	struct c8sectpfei *fei;
 	void __iomem *irec;

drivers/media/radio/wl128x/fmdrv.h

···
 #include <sound/core.h>
 #include <sound/initval.h>
 #include <linux/timer.h>
+#include <linux/workqueue.h>
 #include <media/v4l2-ioctl.h>
 #include <media/v4l2-common.h>
 #include <media/v4l2-device.h>
···
 	int streg_cbdata; /* status of ST registration */
 
 	struct sk_buff_head rx_q;	/* RX queue */
-	struct tasklet_struct rx_task;	/* RX Tasklet */
+	struct work_struct rx_bh_work;	/* RX BH Work */
 
 	struct sk_buff_head tx_q;	/* TX queue */
-	struct tasklet_struct tx_task;	/* TX Tasklet */
+	struct work_struct tx_bh_work;	/* TX BH Work */
 	unsigned long last_tx_jiffies;	/* Timestamp of last pkt sent */
 	atomic_t tx_cnt;	/* Number of packets can send at a time */
 

drivers/media/radio/wl128x/fmdrv_common.c

···
  *     one Channel-8 command to be sent to the chip).
  *  2) Sending each Channel-8 command to the chip and reading
  *     response back over Shared Transport.
- *  3) Managing TX and RX Queues and Tasklets.
+ *  3) Managing TX and RX Queues and BH bh Works.
  *  4) Handling FM Interrupt packet and taking appropriate action.
  *  5) Loading FM firmware to the chip (common, FM TX, and FM RX
  *     firmware files based on mode selection)
···
 }
 
 /*
- * FM common sub-module will schedule this tasklet whenever it receives
+ * FM common sub-module will queue this bh work whenever it receives
  * FM packet from ST driver.
  */
-static void recv_tasklet(struct tasklet_struct *t)
+static void recv_bh_work(struct work_struct *t)
 {
 	struct fmdev *fmdev;
 	struct fm_irq *irq_info;
···
 	u8 num_fm_hci_cmds;
 	unsigned long flags;
 
-	fmdev = from_tasklet(fmdev, t, tx_task);
+	fmdev = from_work(fmdev, t, tx_bh_work);
 	irq_info = &fmdev->irq_info;
 	/* Process all packets in the RX queue */
 	while ((skb = skb_dequeue(&fmdev->rx_q))) {
···
 
 		/*
 		 * Check flow control field. If Num_FM_HCI_Commands field is
-		 * not zero, schedule FM TX tasklet.
+		 * not zero, queue FM TX bh work.
 		 */
 		if (num_fm_hci_cmds && atomic_read(&fmdev->tx_cnt))
 			if (!skb_queue_empty(&fmdev->tx_q))
-				tasklet_schedule(&fmdev->tx_task);
+				queue_work(system_bh_wq, &fmdev->tx_bh_work);
 	}
 }
 
-/* FM send tasklet: is scheduled when FM packet has to be sent to chip */
-static void send_tasklet(struct tasklet_struct *t)
+/* FM send_bh_work: is scheduled when FM packet has to be sent to chip */
+static void send_bh_work(struct work_struct *t)
 {
 	struct fmdev *fmdev;
 	struct sk_buff *skb;
 	int len;
 
-	fmdev = from_tasklet(fmdev, t, tx_task);
+	fmdev = from_work(fmdev, t, tx_bh_work);
 
 	if (!atomic_read(&fmdev->tx_cnt))
 		return;
···
 	if (len < 0) {
 		kfree_skb(skb);
 		fmdev->resp_comp = NULL;
-		fmerr("TX tasklet failed to send skb(%p)\n", skb);
+		fmerr("TX bh work failed to send skb(%p)\n", skb);
 		atomic_set(&fmdev->tx_cnt, 1);
 	} else {
 		fmdev->last_tx_jiffies = jiffies;
···
 }
 
 /*
- * Queues FM Channel-8 packet to FM TX queue and schedules FM TX tasklet for
+ * Queues FM Channel-8 packet to FM TX queue and schedules FM TX bh work for
  * transmission
  */
 static int fm_send_cmd(struct fmdev *fmdev, u8 fm_op, u16 type,	void *payload,
···
 
 	fm_cb(skb)->completion = wait_completion;
 	skb_queue_tail(&fmdev->tx_q, skb);
-	tasklet_schedule(&fmdev->tx_task);
+	queue_work(system_bh_wq, &fmdev->tx_bh_work);
 
 	return 0;
 }
···
 
 	if (!wait_for_completion_timeout(&fmdev->maintask_comp,
 					 FM_DRV_TX_TIMEOUT)) {
-		fmerr("Timeout(%d sec),didn't get regcompletion signal from RX tasklet\n",
+		fmerr("Timeout(%d sec),didn't get regcompletion signal from RX bh work\n",
 			   jiffies_to_msecs(FM_DRV_TX_TIMEOUT) / 1000);
 		return -ETIMEDOUT;
 	}
···
 
 	memcpy(skb_push(skb, 1), &skb->cb[0], 1);
 	skb_queue_tail(&fmdev->rx_q, skb);
-	tasklet_schedule(&fmdev->rx_task);
+	queue_work(system_bh_wq, &fmdev->rx_bh_work);
 
 	return 0;
 }
···
 	spin_lock_init(&fmdev->rds_buff_lock);
 	spin_lock_init(&fmdev->resp_skb_lock);
 
-	/* Initialize TX queue and TX tasklet */
+	/* Initialize TX queue and TX bh work */
 	skb_queue_head_init(&fmdev->tx_q);
-	tasklet_setup(&fmdev->tx_task, send_tasklet);
+	INIT_WORK(&fmdev->tx_bh_work, send_bh_work);
 
-	/* Initialize RX Queue and RX tasklet */
+	/* Initialize RX Queue and RX bh work */
 	skb_queue_head_init(&fmdev->rx_q);
-	tasklet_setup(&fmdev->rx_task, recv_tasklet);
+	INIT_WORK(&fmdev->rx_bh_work, recv_bh_work);
 
 	fmdev->irq_info.stage = 0;
 	atomic_set(&fmdev->tx_cnt, 1);
···
 	/* Service pending read */
 	wake_up_interruptible(&fmdev->rx.rds.read_queue);
 
-	tasklet_kill(&fmdev->tx_task);
-	tasklet_kill(&fmdev->rx_task);
+	cancel_work_sync(&fmdev->tx_bh_work);
+	cancel_work_sync(&fmdev->rx_bh_work);
 
 	skb_queue_purge(&fmdev->tx_q);
 	skb_queue_purge(&fmdev->rx_q);

drivers/media/rc/mceusb.c

···
 
 /*
  * Schedule work that can't be done in interrupt handlers
- * (mceusb_dev_recv() and mce_write_callback()) nor tasklets.
+ * (mceusb_dev_recv() and mce_write_callback()) nor BH work.
  * Invokes mceusb_deferred_kevent() for recovering from
  * error events specified by the kevent bit field.
  */

drivers/media/usb/ttusb-dec/ttusb_dec.c

···
 #include <linux/input.h>
 
 #include <linux/mutex.h>
+#include <linux/workqueue.h>
 
 #include <media/dmxdev.h>
 #include <media/dvb_demux.h>
···
 	int			v_pes_postbytes;
 
 	struct list_head	urb_frame_list;
-	struct tasklet_struct	urb_tasklet;
+	struct work_struct	urb_bh_work;
 	spinlock_t		urb_frame_list_lock;
 
 	struct dvb_demux_filter	*audio_filter;
···
 	}
 }
 
-static void ttusb_dec_process_urb_frame_list(struct tasklet_struct *t)
+static void ttusb_dec_process_urb_frame_list(struct work_struct *t)
 {
-	struct ttusb_dec *dec = from_tasklet(dec, t, urb_tasklet);
+	struct ttusb_dec *dec = from_work(dec, t, urb_bh_work);
 	struct list_head *item;
 	struct urb_frame *frame;
 	unsigned long flags;
···
 				spin_unlock_irqrestore(&dec->urb_frame_list_lock,
 						       flags);
 
-				tasklet_schedule(&dec->urb_tasklet);
+				queue_work(system_bh_wq, &dec->urb_bh_work);
 			}
 		}
 	} else {
···
 	return 0;
 }
 
-static void ttusb_dec_init_tasklet(struct ttusb_dec *dec)
+static void ttusb_dec_init_bh_work(struct ttusb_dec *dec)
 {
 	spin_lock_init(&dec->urb_frame_list_lock);
 	INIT_LIST_HEAD(&dec->urb_frame_list);
-	tasklet_setup(&dec->urb_tasklet, ttusb_dec_process_urb_frame_list);
+	INIT_WORK(&dec->urb_bh_work, ttusb_dec_process_urb_frame_list);
 }
 
 static int ttusb_init_rc( struct ttusb_dec *dec)
···
 	ttusb_dec_free_iso_urbs(dec);
 }
 
-static void ttusb_dec_exit_tasklet(struct ttusb_dec *dec)
+static void ttusb_dec_exit_bh_work(struct ttusb_dec *dec)
 {
 	struct list_head *item;
 	struct urb_frame *frame;
 
-	tasklet_kill(&dec->urb_tasklet);
+	cancel_work_sync(&dec->urb_bh_work);
 
 	while ((item = dec->urb_frame_list.next) != &dec->urb_frame_list) {
 		frame = list_entry(item, struct urb_frame, urb_frame_list);
···
 
 	ttusb_dec_init_v_pes(dec);
 	ttusb_dec_init_filters(dec);
-	ttusb_dec_init_tasklet(dec);
+	ttusb_dec_init_bh_work(dec);
 
 	dec->active = 1;
 
···
 	dprintk("%s\n", __func__);
 
 	if (dec->active) {
-		ttusb_dec_exit_tasklet(dec);
+		ttusb_dec_exit_bh_work(dec);
 		ttusb_dec_exit_filters(dec);
 		if(enable_rc)
 			ttusb_dec_exit_rc(dec);