V4L/DVB (9516): cx18: Move DVB buffer transfer handling from irq handler to work_queue

cx18: Move DVB buffer transfer handling from irq handler to work_queue thread. In order to properly lock the epu2cpu mailbox for driver to CX23418 commands, the DVB/TS buffer handling needs to be moved from the IRQ handler and IRQ context to a work queue. This work_queue implmentation is strikingly similar to the ivtv implementation - for better or worse. Signed-off-by: Andy Walls <awalls@radix.net> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

V4L/DVB (9516): cx18: Move DVB buffer transfer handling from irq handler to work_queue
cx18: Move DVB buffer transfer handling from irq handler to work_queue thread. In order to properly lock the epu2cpu mailbox for driver to CX23418 commands, the DVB/TS buffer handling needs to be moved from the IRQ handler and IRQ context to a work queue. This work_queue implmentation is strikingly similar to the ivtv implementation - for better or worse. Signed-off-by: Andy Walls <awalls@radix.net> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Andy Walls · Mauro Carvalho Chehab
1 parent c9ff1b689a
Showing 7 changed files with 75 additions and 26 deletions Side-by-side Diff
drivers/media/video/cx18/cx18-driver.c
drivers/media/video/cx18/cx18-driver.h
drivers/media/video/cx18/cx18-dvb.c
drivers/media/video/cx18/cx18-dvb.h
drivers/media/video/cx18/cx18-irq.c
drivers/media/video/cx18/cx18-irq.h
drivers/media/video/cx18/cx18-queue.c
@@ -449,6 +449,14 @@
  
 	spin_lock_init(&cx->lock);
  
+	cx->work_queue = create_singlethread_workqueue(cx->name);
+	if (cx->work_queue == NULL) {
+		CX18_ERR("Could not create work queue\n");
+		return -1;
+	}
+
+	INIT_WORK(&cx->work, cx18_work_handler);
+
 	/* start counting open_id at 1 */
 	cx->open_id = 1;
  
@@ -831,6 +839,7 @@
 free_mem:
 	release_mem_region(cx->base_addr, CX18_MEM_SIZE);
 free_workqueue:
+	destroy_workqueue(cx->work_queue);
 err:
 	if (retval == 0)
 		retval = -ENODEV;
@@ -930,6 +939,9 @@
 	cx18_sw2_irq_disable(cx, IRQ_CPU_TO_EPU_ACK | IRQ_APU_TO_EPU_ACK);
  
 	cx18_halt_firmware(cx);
+
+	flush_workqueue(cx->work_queue);
+	destroy_workqueue(cx->work_queue);
  
 	cx18_streams_cleanup(cx, 1);
  
@@ -199,12 +199,15 @@
 #define CX18_F_S_APPL_IO        8	/* this stream is used read/written by an application */
  
 /* per-cx18, i_flags */
-#define CX18_F_I_LOADED_FW	0 	/* Loaded the firmware the first time */
-#define CX18_F_I_EOS		4 	/* End of encoder stream reached */
-#define CX18_F_I_RADIO_USER	5 	/* The radio tuner is selected */
-#define CX18_F_I_ENC_PAUSED	13 	/* the encoder is paused */
-#define CX18_F_I_INITED		21 	/* set after first open */
-#define CX18_F_I_FAILED		22 	/* set if first open failed */
+#define CX18_F_I_LOADED_FW		0 	/* Loaded firmware 1st time */
+#define CX18_F_I_EOS			4 	/* End of encoder stream */
+#define CX18_F_I_RADIO_USER		5 	/* radio tuner is selected */
+#define CX18_F_I_ENC_PAUSED		13 	/* the encoder is paused */
+#define CX18_F_I_HAVE_WORK		15   	/* there is work to be done */
+#define CX18_F_I_WORK_HANDLER_DVB	18   	/* work to be done for DVB */
+#define CX18_F_I_INITED			21 	/* set after first open */
+#define CX18_F_I_FAILED			22 	/* set if first open failed */
+#define CX18_F_I_WORK_INITED		23	/* worker thread initialized */
  
 /* These are the VBI types as they appear in the embedded VBI private packets. */
 #define CX18_SLICED_TYPE_TELETEXT_B     (1)
@@ -430,6 +433,9 @@
 	wait_queue_head_t cap_w;
 	/* when the current DMA is finished this queue is woken up */
 	wait_queue_head_t dma_waitq;
+
+	struct workqueue_struct *work_queue;
+	struct work_struct work;
  
 	/* i2c */
 	struct i2c_adapter i2c_adap[2];
@@ -23,6 +23,8 @@
 #include "cx18-dvb.h"
 #include "cx18-io.h"
 #include "cx18-streams.h"
+#include "cx18-queue.h"
+#include "cx18-scb.h"
 #include "cx18-cards.h"
 #include "s5h1409.h"
 #include "mxl5005s.h"
@@ -299,5 +301,26 @@
 	}
  
 	return ret;
+}
+
+void cx18_dvb_work_handler(struct cx18 *cx)
+{
+	struct cx18_buffer *buf;
+	struct cx18_stream *s = &cx->streams[CX18_ENC_STREAM_TYPE_TS];
+
+	while ((buf = cx18_dequeue(s, &s->q_full)) != NULL) {
+		if (s->dvb.enabled)
+			dvb_dmx_swfilter(&s->dvb.demux, buf->buf,
+					 buf->bytesused);
+
+		cx18_enqueue(s, buf, &s->q_free);
+		cx18_buf_sync_for_device(s, buf);
+		if (s->handle == CX18_INVALID_TASK_HANDLE) /* FIXME: improve */
+			continue;
+
+		cx18_vapi(cx, CX18_CPU_DE_SET_MDL, 5, s->handle,
+		       (void __iomem *)&cx->scb->cpu_mdl[buf->id] - cx->enc_mem,
+		       1, buf->id, s->buf_size);
+	}
 }
@@ -23,4 +23,5 @@
  
 int cx18_dvb_register(struct cx18_stream *stream);
 void cx18_dvb_unregister(struct cx18_stream *stream);
+void cx18_dvb_work_handler(struct cx18 *cx);
@@ -29,7 +29,21 @@
 #include "cx18-mailbox.h"
 #include "cx18-vbi.h"
 #include "cx18-scb.h"
+#include "cx18-dvb.h"
  
+void cx18_work_handler(struct work_struct *work)
+{
+	struct cx18 *cx = container_of(work, struct cx18, work);
+	if (test_and_clear_bit(CX18_F_I_WORK_INITED, &cx->i_flags)) {
+		struct sched_param param = { .sched_priority = MAX_RT_PRIO-1 };
+		/* This thread must use the FIFO scheduler as it
+		 * is realtime sensitive. */
+		sched_setscheduler(current, SCHED_FIFO, &param);
+	}
+	if (test_and_clear_bit(CX18_F_I_WORK_HANDLER_DVB, &cx->i_flags))
+		cx18_dvb_work_handler(cx);
+}
+
 static void epu_dma_done(struct cx18 *cx, struct cx18_mailbox *mb)
 {
 	u32 handle = mb->args[0];
  
@@ -65,17 +79,11 @@
 	if (buf) {
 		cx18_buf_sync_for_cpu(s, buf);
 		if (s->type == CX18_ENC_STREAM_TYPE_TS && s->dvb.enabled) {
-			/* process the buffer here */
-			CX18_DEBUG_HI_DMA("TS recv and sent bytesused=%d\n",
+			CX18_DEBUG_HI_DMA("TS recv bytesused = %d\n",
 					buf->bytesused);
  
-			dvb_dmx_swfilter(&s->dvb.demux, buf->buf,
-					buf->bytesused);
-
-			cx18_buf_sync_for_device(s, buf);
-			cx18_vapi(cx, CX18_CPU_DE_SET_MDL, 5, s->handle,
-			    (void __iomem *)&cx->scb->cpu_mdl[buf->id] - cx->enc_mem,
-			    1, buf->id, s->buf_size);
+			set_bit(CX18_F_I_WORK_HANDLER_DVB, &cx->i_flags);
+			set_bit(CX18_F_I_HAVE_WORK, &cx->i_flags);
 		} else
 			set_bit(CX18_F_B_NEED_BUF_SWAP, &buf->b_flags);
 	} else {
@@ -184,6 +192,9 @@
  
 	if (sw1)
 		epu_cmd(cx, sw1);
+
+	if (test_and_clear_bit(CX18_F_I_HAVE_WORK, &cx->i_flags))
+		queue_work(cx->work_queue, &cx->work);
  
 	return (sw1 || sw2 || hw2) ? IRQ_HANDLED : IRQ_NONE;
 }
@@ -32,7 +32,5 @@
  
 irqreturn_t cx18_irq_handler(int irq, void *dev_id);
  
-void cx18_irq_work_handler(struct work_struct *work);
-void cx18_dma_stream_dec_prepare(struct cx18_stream *s, u32 offset, int lock);
-void cx18_unfinished_dma(unsigned long arg);
+void cx18_work_handler(struct work_struct *work);
@@ -88,15 +88,13 @@
  
 		if (buf->id != id)
 			continue;
+
 		buf->bytesused = bytesused;
-		/* the transport buffers are handled differently,
-		   they are not moved to the full queue */
-		if (s->type != CX18_ENC_STREAM_TYPE_TS) {
-			atomic_dec(&s->q_free.buffers);
-			atomic_inc(&s->q_full.buffers);
-			s->q_full.bytesused += buf->bytesused;
-			list_move_tail(&buf->list, &s->q_full.list);
-		}
+		atomic_dec(&s->q_free.buffers);
+		atomic_inc(&s->q_full.buffers);
+		s->q_full.bytesused += buf->bytesused;
+		list_move_tail(&buf->list, &s->q_full.list);
+
 		spin_unlock(&s->qlock);
 		return buf;
 	}
...	...	@@ -449,6 +449,14 @@
449	449
450	450	spin_lock_init(&cx->lock);
451	451
	452	+ cx->work_queue = create_singlethread_workqueue(cx->name);
	453	+ if (cx->work_queue == NULL) {
	454	+ CX18_ERR("Could not create work queue\n");
	455	+ return -1;
	456	+ }
	457	+
	458	+ INIT_WORK(&cx->work, cx18_work_handler);
	459	+
452	460	/* start counting open_id at 1 */
453	461	cx->open_id = 1;
454	462
...	...	@@ -831,6 +839,7 @@
831	839	free_mem:
832	840	release_mem_region(cx->base_addr, CX18_MEM_SIZE);
833	841	free_workqueue:
	842	+ destroy_workqueue(cx->work_queue);
834	843	err:
835	844	if (retval == 0)
836	845	retval = -ENODEV;
...	...	@@ -930,6 +939,9 @@
930	939	cx18_sw2_irq_disable(cx, IRQ_CPU_TO_EPU_ACK \| IRQ_APU_TO_EPU_ACK);
931	940
932	941	cx18_halt_firmware(cx);
	942	+
	943	+ flush_workqueue(cx->work_queue);
	944	+ destroy_workqueue(cx->work_queue);
933	945
934	946	cx18_streams_cleanup(cx, 1);
935	947
...	...	@@ -199,12 +199,15 @@
199	199	#define CX18_F_S_APPL_IO 8 /* this stream is used read/written by an application */
200	200
201	201	/* per-cx18, i_flags */
202		-#define CX18_F_I_LOADED_FW 0 /* Loaded the firmware the first time */
203		-#define CX18_F_I_EOS 4 /* End of encoder stream reached */
204		-#define CX18_F_I_RADIO_USER 5 /* The radio tuner is selected */
205		-#define CX18_F_I_ENC_PAUSED 13 /* the encoder is paused */
206		-#define CX18_F_I_INITED 21 /* set after first open */
207		-#define CX18_F_I_FAILED 22 /* set if first open failed */
	202	+#define CX18_F_I_LOADED_FW 0 /* Loaded firmware 1st time */
	203	+#define CX18_F_I_EOS 4 /* End of encoder stream */
	204	+#define CX18_F_I_RADIO_USER 5 /* radio tuner is selected */
	205	+#define CX18_F_I_ENC_PAUSED 13 /* the encoder is paused */
	206	+#define CX18_F_I_HAVE_WORK 15 /* there is work to be done */
	207	+#define CX18_F_I_WORK_HANDLER_DVB 18 /* work to be done for DVB */
	208	+#define CX18_F_I_INITED 21 /* set after first open */
	209	+#define CX18_F_I_FAILED 22 /* set if first open failed */
	210	+#define CX18_F_I_WORK_INITED 23 /* worker thread initialized */
208	211
209	212	/* These are the VBI types as they appear in the embedded VBI private packets. */
210	213	#define CX18_SLICED_TYPE_TELETEXT_B (1)
...	...	@@ -430,6 +433,9 @@
430	433	wait_queue_head_t cap_w;
431	434	/* when the current DMA is finished this queue is woken up */
432	435	wait_queue_head_t dma_waitq;
	436	+
	437	+ struct workqueue_struct *work_queue;
	438	+ struct work_struct work;
433	439
434	440	/* i2c */
435	441	struct i2c_adapter i2c_adap[2];
...	...	@@ -23,6 +23,8 @@
23	23	#include "cx18-dvb.h"
24	24	#include "cx18-io.h"
25	25	#include "cx18-streams.h"
	26	+#include "cx18-queue.h"
	27	+#include "cx18-scb.h"
26	28	#include "cx18-cards.h"
27	29	#include "s5h1409.h"
28	30	#include "mxl5005s.h"
...	...	@@ -299,5 +301,26 @@
299	301	}
300	302
301	303	return ret;
	304	+}
	305	+
	306	+void cx18_dvb_work_handler(struct cx18 *cx)
	307	+{
	308	+ struct cx18_buffer *buf;
	309	+ struct cx18_stream *s = &cx->streams[CX18_ENC_STREAM_TYPE_TS];
	310	+
	311	+ while ((buf = cx18_dequeue(s, &s->q_full)) != NULL) {
	312	+ if (s->dvb.enabled)
	313	+ dvb_dmx_swfilter(&s->dvb.demux, buf->buf,
	314	+ buf->bytesused);
	315	+
	316	+ cx18_enqueue(s, buf, &s->q_free);
	317	+ cx18_buf_sync_for_device(s, buf);
	318	+ if (s->handle == CX18_INVALID_TASK_HANDLE) /* FIXME: improve */
	319	+ continue;
	320	+
	321	+ cx18_vapi(cx, CX18_CPU_DE_SET_MDL, 5, s->handle,
	322	+ (void __iomem *)&cx->scb->cpu_mdl[buf->id] - cx->enc_mem,
	323	+ 1, buf->id, s->buf_size);
	324	+ }
302	325	}
...	...	@@ -23,4 +23,5 @@
23	23
24	24	int cx18_dvb_register(struct cx18_stream *stream);
25	25	void cx18_dvb_unregister(struct cx18_stream *stream);
	26	+void cx18_dvb_work_handler(struct cx18 *cx);
...	...	@@ -29,7 +29,21 @@
29	29	#include "cx18-mailbox.h"
30	30	#include "cx18-vbi.h"
31	31	#include "cx18-scb.h"
	32	+#include "cx18-dvb.h"
32	33
	34	+void cx18_work_handler(struct work_struct *work)
	35	+{
	36	+ struct cx18 *cx = container_of(work, struct cx18, work);
	37	+ if (test_and_clear_bit(CX18_F_I_WORK_INITED, &cx->i_flags)) {
	38	+ struct sched_param param = { .sched_priority = MAX_RT_PRIO-1 };
	39	+ /* This thread must use the FIFO scheduler as it
	40	+ * is realtime sensitive. */
	41	+ sched_setscheduler(current, SCHED_FIFO, &param);
	42	+ }
	43	+ if (test_and_clear_bit(CX18_F_I_WORK_HANDLER_DVB, &cx->i_flags))
	44	+ cx18_dvb_work_handler(cx);
	45	+}
	46	+
33	47	static void epu_dma_done(struct cx18 cx, struct cx18_mailbox mb)
34	48	{
35	49	u32 handle = mb->args[0];
36	50
...	...	@@ -65,17 +79,11 @@
65	79	if (buf) {
66	80	cx18_buf_sync_for_cpu(s, buf);
67	81	if (s->type == CX18_ENC_STREAM_TYPE_TS && s->dvb.enabled) {
68		- /* process the buffer here */
69		- CX18_DEBUG_HI_DMA("TS recv and sent bytesused=%d\n",
	82	+ CX18_DEBUG_HI_DMA("TS recv bytesused = %d\n",
70	83	buf->bytesused);
71	84
72		- dvb_dmx_swfilter(&s->dvb.demux, buf->buf,
73		- buf->bytesused);
74		-
75		- cx18_buf_sync_for_device(s, buf);
76		- cx18_vapi(cx, CX18_CPU_DE_SET_MDL, 5, s->handle,
77		- (void __iomem *)&cx->scb->cpu_mdl[buf->id] - cx->enc_mem,
78		- 1, buf->id, s->buf_size);
	85	+ set_bit(CX18_F_I_WORK_HANDLER_DVB, &cx->i_flags);
	86	+ set_bit(CX18_F_I_HAVE_WORK, &cx->i_flags);
79	87	} else
80	88	set_bit(CX18_F_B_NEED_BUF_SWAP, &buf->b_flags);
81	89	} else {
...	...	@@ -184,6 +192,9 @@
184	192
185	193	if (sw1)
186	194	epu_cmd(cx, sw1);
	195	+
	196	+ if (test_and_clear_bit(CX18_F_I_HAVE_WORK, &cx->i_flags))
	197	+ queue_work(cx->work_queue, &cx->work);
187	198
188	199	return (sw1 \|\| sw2 \|\| hw2) ? IRQ_HANDLED : IRQ_NONE;
189	200	}
...	...	@@ -32,7 +32,5 @@
32	32
33	33	irqreturn_t cx18_irq_handler(int irq, void *dev_id);
34	34
35		-void cx18_irq_work_handler(struct work_struct *work);
36		-void cx18_dma_stream_dec_prepare(struct cx18_stream *s, u32 offset, int lock);
37		-void cx18_unfinished_dma(unsigned long arg);
	35	+void cx18_work_handler(struct work_struct *work);
...	...	@@ -88,15 +88,13 @@
88	88
89	89	if (buf->id != id)
90	90	continue;
	91	+
91	92	buf->bytesused = bytesused;
92		- /* the transport buffers are handled differently,
93		- they are not moved to the full queue */
94		- if (s->type != CX18_ENC_STREAM_TYPE_TS) {
95		- atomic_dec(&s->q_free.buffers);
96		- atomic_inc(&s->q_full.buffers);
97		- s->q_full.bytesused += buf->bytesused;
98		- list_move_tail(&buf->list, &s->q_full.list);
99		- }
	93	+ atomic_dec(&s->q_free.buffers);
	94	+ atomic_inc(&s->q_full.buffers);
	95	+ s->q_full.bytesused += buf->bytesused;
	96	+ list_move_tail(&buf->list, &s->q_full.list);
	97	+
100	98	spin_unlock(&s->qlock);
101	99	return buf;
102	100	}