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>

1 files changed, 20 insertions, 9 deletions

diff --git a/drivers/media/video/cx18/cx18-irq.c b/drivers/media/video/cx18/cx18-irq.c
index c306e142c1c..5fbfbd0f149 100644
--- a/drivers/media/video/cx18/cx18-irq.c
+++ b/drivers/media/video/cx18/cx18-irq.c
@@ -29,6 +29,20 @@
 #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)
 {
@@ -65,17 +79,11 @@ static void epu_dma_done(struct cx18 *cx, struct cx18_mailbox *mb)
         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 {
@@ -185,5 +193,8 @@ irqreturn_t cx18_irq_handler(int irq, void *dev_id)
         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;
 }