GNU Linux-libre 6.7.9-gnu
[releases.git] / drivers / media / usb / cx231xx / cx231xx-vbi.c
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3    cx231xx_vbi.c - driver for Conexant Cx23100/101/102 USB video capture devices
4
5    Copyright (C) 2008 <srinivasa.deevi at conexant dot com>
6         Based on cx88 driver
7
8  */
9
10 #include "cx231xx.h"
11 #include <linux/init.h>
12 #include <linux/list.h>
13 #include <linux/module.h>
14 #include <linux/kernel.h>
15 #include <linux/bitmap.h>
16 #include <linux/i2c.h>
17 #include <linux/mm.h>
18 #include <linux/mutex.h>
19 #include <linux/slab.h>
20
21 #include <media/v4l2-common.h>
22 #include <media/v4l2-ioctl.h>
23 #include <media/drv-intf/msp3400.h>
24 #include <media/tuner.h>
25
26 #include "cx231xx-vbi.h"
27
28 static inline void print_err_status(struct cx231xx *dev, int packet, int status)
29 {
30         char *errmsg = "Unknown";
31
32         switch (status) {
33         case -ENOENT:
34                 errmsg = "unlinked synchronously";
35                 break;
36         case -ECONNRESET:
37                 errmsg = "unlinked asynchronously";
38                 break;
39         case -ENOSR:
40                 errmsg = "Buffer error (overrun)";
41                 break;
42         case -EPIPE:
43                 errmsg = "Stalled (device not responding)";
44                 break;
45         case -EOVERFLOW:
46                 errmsg = "Babble (bad cable?)";
47                 break;
48         case -EPROTO:
49                 errmsg = "Bit-stuff error (bad cable?)";
50                 break;
51         case -EILSEQ:
52                 errmsg = "CRC/Timeout (could be anything)";
53                 break;
54         case -ETIME:
55                 errmsg = "Device does not respond";
56                 break;
57         }
58         if (packet < 0) {
59                 dev_err(dev->dev,
60                         "URB status %d [%s].\n", status, errmsg);
61         } else {
62                 dev_err(dev->dev,
63                         "URB packet %d, status %d [%s].\n",
64                         packet, status, errmsg);
65         }
66 }
67
68 /*
69  * Controls the isoc copy of each urb packet
70  */
71 static inline int cx231xx_isoc_vbi_copy(struct cx231xx *dev, struct urb *urb)
72 {
73         struct cx231xx_dmaqueue *dma_q = urb->context;
74         int rc = 1;
75         unsigned char *p_buffer;
76         u32 bytes_parsed = 0, buffer_size = 0;
77         u8 sav_eav = 0;
78
79         if (!dev)
80                 return 0;
81
82         if (dev->state & DEV_DISCONNECTED)
83                 return 0;
84
85         if (urb->status < 0) {
86                 print_err_status(dev, -1, urb->status);
87                 if (urb->status == -ENOENT)
88                         return 0;
89         }
90
91         /* get buffer pointer and length */
92         p_buffer = urb->transfer_buffer;
93         buffer_size = urb->actual_length;
94
95         if (buffer_size > 0) {
96                 bytes_parsed = 0;
97
98                 if (dma_q->is_partial_line) {
99                         /* Handle the case where we were working on a partial
100                            line */
101                         sav_eav = dma_q->last_sav;
102                 } else {
103                         /* Check for a SAV/EAV overlapping the
104                            buffer boundary */
105
106                         sav_eav = cx231xx_find_boundary_SAV_EAV(p_buffer,
107                                                           dma_q->partial_buf,
108                                                           &bytes_parsed);
109                 }
110
111                 sav_eav &= 0xF0;
112                 /* Get the first line if we have some portion of an SAV/EAV from
113                    the last buffer or a partial line */
114                 if (sav_eav) {
115                         bytes_parsed += cx231xx_get_vbi_line(dev, dma_q,
116                                 sav_eav,                       /* SAV/EAV */
117                                 p_buffer + bytes_parsed,       /* p_buffer */
118                                 buffer_size - bytes_parsed);   /* buffer size */
119                 }
120
121                 /* Now parse data that is completely in this buffer */
122                 dma_q->is_partial_line = 0;
123
124                 while (bytes_parsed < buffer_size) {
125                         u32 bytes_used = 0;
126
127                         sav_eav = cx231xx_find_next_SAV_EAV(
128                                 p_buffer + bytes_parsed,        /* p_buffer */
129                                 buffer_size - bytes_parsed, /* buffer size */
130                                 &bytes_used);   /* bytes used to get SAV/EAV */
131
132                         bytes_parsed += bytes_used;
133
134                         sav_eav &= 0xF0;
135                         if (sav_eav && (bytes_parsed < buffer_size)) {
136                                 bytes_parsed += cx231xx_get_vbi_line(dev,
137                                         dma_q, sav_eav, /* SAV/EAV */
138                                         p_buffer+bytes_parsed, /* p_buffer */
139                                         buffer_size-bytes_parsed);/*buf size*/
140                         }
141                 }
142
143                 /* Save the last four bytes of the buffer so we can
144                 check the buffer boundary condition next time */
145                 memcpy(dma_q->partial_buf, p_buffer + buffer_size - 4, 4);
146                 bytes_parsed = 0;
147         }
148
149         return rc;
150 }
151
152 /* ------------------------------------------------------------------
153         Vbi buf operations
154    ------------------------------------------------------------------*/
155
156 static int vbi_queue_setup(struct vb2_queue *vq,
157                            unsigned int *nbuffers, unsigned int *nplanes,
158                            unsigned int sizes[], struct device *alloc_devs[])
159 {
160         struct cx231xx *dev = vb2_get_drv_priv(vq);
161         u32 height = 0;
162
163         height = ((dev->norm & V4L2_STD_625_50) ?
164                   PAL_VBI_LINES : NTSC_VBI_LINES);
165
166         *nplanes = 1;
167         sizes[0] = (dev->width * height * 2 * 2);
168         return 0;
169 }
170
171 /* This is called *without* dev->slock held; please keep it that way */
172 static int vbi_buf_prepare(struct vb2_buffer *vb)
173 {
174         struct cx231xx *dev = vb2_get_drv_priv(vb->vb2_queue);
175         u32 height = 0;
176         u32 size;
177
178         height = ((dev->norm & V4L2_STD_625_50) ?
179                   PAL_VBI_LINES : NTSC_VBI_LINES);
180         size = ((dev->width << 1) * height * 2);
181
182         if (vb2_plane_size(vb, 0) < size)
183                 return -EINVAL;
184         vb2_set_plane_payload(vb, 0, size);
185         return 0;
186 }
187
188 static void vbi_buf_queue(struct vb2_buffer *vb)
189 {
190         struct cx231xx *dev = vb2_get_drv_priv(vb->vb2_queue);
191         struct cx231xx_buffer *buf =
192             container_of(vb, struct cx231xx_buffer, vb.vb2_buf);
193         struct cx231xx_dmaqueue *vidq = &dev->vbi_mode.vidq;
194         unsigned long flags;
195
196         spin_lock_irqsave(&dev->vbi_mode.slock, flags);
197         list_add_tail(&buf->list, &vidq->active);
198         spin_unlock_irqrestore(&dev->vbi_mode.slock, flags);
199 }
200
201 static void return_all_buffers(struct cx231xx *dev,
202                                enum vb2_buffer_state state)
203 {
204         struct cx231xx_dmaqueue *vidq = &dev->vbi_mode.vidq;
205         struct cx231xx_buffer *buf, *node;
206         unsigned long flags;
207
208         spin_lock_irqsave(&dev->vbi_mode.slock, flags);
209         dev->vbi_mode.bulk_ctl.buf = NULL;
210         list_for_each_entry_safe(buf, node, &vidq->active, list) {
211                 list_del(&buf->list);
212                 vb2_buffer_done(&buf->vb.vb2_buf, state);
213         }
214         spin_unlock_irqrestore(&dev->vbi_mode.slock, flags);
215 }
216
217 static int vbi_start_streaming(struct vb2_queue *vq, unsigned int count)
218 {
219         struct cx231xx *dev = vb2_get_drv_priv(vq);
220         struct cx231xx_dmaqueue *vidq = &dev->vbi_mode.vidq;
221         int ret;
222
223         vidq->sequence = 0;
224         ret = cx231xx_init_vbi_isoc(dev, CX231XX_NUM_VBI_PACKETS,
225                                     CX231XX_NUM_VBI_BUFS,
226                                     dev->vbi_mode.alt_max_pkt_size[0],
227                                     cx231xx_isoc_vbi_copy);
228         if (ret)
229                 return_all_buffers(dev, VB2_BUF_STATE_QUEUED);
230         return ret;
231 }
232
233 static void vbi_stop_streaming(struct vb2_queue *vq)
234 {
235         struct cx231xx *dev = vb2_get_drv_priv(vq);
236
237         return_all_buffers(dev, VB2_BUF_STATE_ERROR);
238 }
239
240 struct vb2_ops cx231xx_vbi_qops = {
241         .queue_setup = vbi_queue_setup,
242         .buf_prepare = vbi_buf_prepare,
243         .buf_queue = vbi_buf_queue,
244         .start_streaming = vbi_start_streaming,
245         .stop_streaming = vbi_stop_streaming,
246         .wait_prepare = vb2_ops_wait_prepare,
247         .wait_finish = vb2_ops_wait_finish,
248 };
249
250 /* ------------------------------------------------------------------
251         URB control
252    ------------------------------------------------------------------*/
253
254 /*
255  * IRQ callback, called by URB callback
256  */
257 static void cx231xx_irq_vbi_callback(struct urb *urb)
258 {
259         struct cx231xx_dmaqueue *dma_q = urb->context;
260         struct cx231xx_video_mode *vmode =
261             container_of(dma_q, struct cx231xx_video_mode, vidq);
262         struct cx231xx *dev = container_of(vmode, struct cx231xx, vbi_mode);
263         unsigned long flags;
264
265         switch (urb->status) {
266         case 0:         /* success */
267         case -ETIMEDOUT:        /* NAK */
268                 break;
269         case -ECONNRESET:       /* kill */
270         case -ENOENT:
271         case -ESHUTDOWN:
272                 return;
273         default:                /* error */
274                 dev_err(dev->dev,
275                         "urb completion error %d.\n", urb->status);
276                 break;
277         }
278
279         /* Copy data from URB */
280         spin_lock_irqsave(&dev->vbi_mode.slock, flags);
281         dev->vbi_mode.bulk_ctl.bulk_copy(dev, urb);
282         spin_unlock_irqrestore(&dev->vbi_mode.slock, flags);
283
284         /* Reset status */
285         urb->status = 0;
286
287         urb->status = usb_submit_urb(urb, GFP_ATOMIC);
288         if (urb->status) {
289                 dev_err(dev->dev, "urb resubmit failed (error=%i)\n",
290                         urb->status);
291         }
292 }
293
294 /*
295  * Stop and Deallocate URBs
296  */
297 void cx231xx_uninit_vbi_isoc(struct cx231xx *dev)
298 {
299         struct urb *urb;
300         int i;
301
302         dev_dbg(dev->dev, "called cx231xx_uninit_vbi_isoc\n");
303
304         dev->vbi_mode.bulk_ctl.nfields = -1;
305         for (i = 0; i < dev->vbi_mode.bulk_ctl.num_bufs; i++) {
306                 urb = dev->vbi_mode.bulk_ctl.urb[i];
307                 if (urb) {
308                         if (!irqs_disabled())
309                                 usb_kill_urb(urb);
310                         else
311                                 usb_unlink_urb(urb);
312
313                         if (dev->vbi_mode.bulk_ctl.transfer_buffer[i]) {
314
315                                 kfree(dev->vbi_mode.bulk_ctl.
316                                       transfer_buffer[i]);
317                                 dev->vbi_mode.bulk_ctl.transfer_buffer[i] =
318                                     NULL;
319                         }
320                         usb_free_urb(urb);
321                         dev->vbi_mode.bulk_ctl.urb[i] = NULL;
322                 }
323                 dev->vbi_mode.bulk_ctl.transfer_buffer[i] = NULL;
324         }
325
326         kfree(dev->vbi_mode.bulk_ctl.urb);
327         kfree(dev->vbi_mode.bulk_ctl.transfer_buffer);
328
329         dev->vbi_mode.bulk_ctl.urb = NULL;
330         dev->vbi_mode.bulk_ctl.transfer_buffer = NULL;
331         dev->vbi_mode.bulk_ctl.num_bufs = 0;
332
333         cx231xx_capture_start(dev, 0, Vbi);
334 }
335 EXPORT_SYMBOL_GPL(cx231xx_uninit_vbi_isoc);
336
337 /*
338  * Allocate URBs and start IRQ
339  */
340 int cx231xx_init_vbi_isoc(struct cx231xx *dev, int max_packets,
341                           int num_bufs, int max_pkt_size,
342                           int (*bulk_copy) (struct cx231xx *dev,
343                                             struct urb *urb))
344 {
345         struct cx231xx_dmaqueue *dma_q = &dev->vbi_mode.vidq;
346         int i;
347         int sb_size, pipe;
348         struct urb *urb;
349         int rc;
350
351         dev_dbg(dev->dev, "called cx231xx_vbi_isoc\n");
352
353         /* De-allocates all pending stuff */
354         cx231xx_uninit_vbi_isoc(dev);
355
356         /* clear if any halt */
357         usb_clear_halt(dev->udev,
358                        usb_rcvbulkpipe(dev->udev,
359                                        dev->vbi_mode.end_point_addr));
360
361         dev->vbi_mode.bulk_ctl.bulk_copy = bulk_copy;
362         dev->vbi_mode.bulk_ctl.num_bufs = num_bufs;
363         dma_q->pos = 0;
364         dma_q->is_partial_line = 0;
365         dma_q->last_sav = 0;
366         dma_q->current_field = -1;
367         dma_q->bytes_left_in_line = dev->width << 1;
368         dma_q->lines_per_field = ((dev->norm & V4L2_STD_625_50) ?
369                                   PAL_VBI_LINES : NTSC_VBI_LINES);
370         dma_q->lines_completed = 0;
371         for (i = 0; i < 8; i++)
372                 dma_q->partial_buf[i] = 0;
373
374         dev->vbi_mode.bulk_ctl.urb = kcalloc(num_bufs, sizeof(void *),
375                                              GFP_KERNEL);
376         if (!dev->vbi_mode.bulk_ctl.urb) {
377                 dev_err(dev->dev,
378                         "cannot alloc memory for usb buffers\n");
379                 return -ENOMEM;
380         }
381
382         dev->vbi_mode.bulk_ctl.transfer_buffer =
383             kcalloc(num_bufs, sizeof(void *), GFP_KERNEL);
384         if (!dev->vbi_mode.bulk_ctl.transfer_buffer) {
385                 dev_err(dev->dev,
386                         "cannot allocate memory for usbtransfer\n");
387                 kfree(dev->vbi_mode.bulk_ctl.urb);
388                 return -ENOMEM;
389         }
390
391         dev->vbi_mode.bulk_ctl.max_pkt_size = max_pkt_size;
392         dev->vbi_mode.bulk_ctl.buf = NULL;
393
394         sb_size = max_packets * dev->vbi_mode.bulk_ctl.max_pkt_size;
395
396         /* allocate urbs and transfer buffers */
397         for (i = 0; i < dev->vbi_mode.bulk_ctl.num_bufs; i++) {
398
399                 urb = usb_alloc_urb(0, GFP_KERNEL);
400                 if (!urb) {
401                         cx231xx_uninit_vbi_isoc(dev);
402                         return -ENOMEM;
403                 }
404                 dev->vbi_mode.bulk_ctl.urb[i] = urb;
405                 urb->transfer_flags = 0;
406
407                 dev->vbi_mode.bulk_ctl.transfer_buffer[i] =
408                     kzalloc(sb_size, GFP_KERNEL);
409                 if (!dev->vbi_mode.bulk_ctl.transfer_buffer[i]) {
410                         dev_err(dev->dev,
411                                 "unable to allocate %i bytes for transfer buffer %i\n",
412                                 sb_size, i);
413                         cx231xx_uninit_vbi_isoc(dev);
414                         return -ENOMEM;
415                 }
416
417                 pipe = usb_rcvbulkpipe(dev->udev, dev->vbi_mode.end_point_addr);
418                 usb_fill_bulk_urb(urb, dev->udev, pipe,
419                                   dev->vbi_mode.bulk_ctl.transfer_buffer[i],
420                                   sb_size, cx231xx_irq_vbi_callback, dma_q);
421         }
422
423         init_waitqueue_head(&dma_q->wq);
424
425         /* submit urbs and enables IRQ */
426         for (i = 0; i < dev->vbi_mode.bulk_ctl.num_bufs; i++) {
427                 rc = usb_submit_urb(dev->vbi_mode.bulk_ctl.urb[i], GFP_ATOMIC);
428                 if (rc) {
429                         dev_err(dev->dev,
430                                 "submit of urb %i failed (error=%i)\n", i, rc);
431                         cx231xx_uninit_vbi_isoc(dev);
432                         return rc;
433                 }
434         }
435
436         cx231xx_capture_start(dev, 1, Vbi);
437
438         return 0;
439 }
440 EXPORT_SYMBOL_GPL(cx231xx_init_vbi_isoc);
441
442 u32 cx231xx_get_vbi_line(struct cx231xx *dev, struct cx231xx_dmaqueue *dma_q,
443                          u8 sav_eav, u8 *p_buffer, u32 buffer_size)
444 {
445         u32 bytes_copied = 0;
446         int current_field = -1;
447
448         switch (sav_eav) {
449
450         case SAV_VBI_FIELD1:
451                 current_field = 1;
452                 break;
453
454         case SAV_VBI_FIELD2:
455                 current_field = 2;
456                 break;
457         default:
458                 break;
459         }
460
461         if (current_field < 0)
462                 return bytes_copied;
463
464         dma_q->last_sav = sav_eav;
465
466         bytes_copied =
467             cx231xx_copy_vbi_line(dev, dma_q, p_buffer, buffer_size,
468                                   current_field);
469
470         return bytes_copied;
471 }
472
473 /*
474  * Announces that a buffer were filled and request the next
475  */
476 static inline void vbi_buffer_filled(struct cx231xx *dev,
477                                      struct cx231xx_dmaqueue *dma_q,
478                                      struct cx231xx_buffer *buf)
479 {
480         /* Advice that buffer was filled */
481         /* dev_dbg(dev->dev, "[%p/%d] wakeup\n", buf, buf->vb.index); */
482
483         buf->vb.sequence = dma_q->sequence++;
484         buf->vb.vb2_buf.timestamp = ktime_get_ns();
485
486         dev->vbi_mode.bulk_ctl.buf = NULL;
487
488         list_del(&buf->list);
489         vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_DONE);
490 }
491
492 u32 cx231xx_copy_vbi_line(struct cx231xx *dev, struct cx231xx_dmaqueue *dma_q,
493                           u8 *p_line, u32 length, int field_number)
494 {
495         u32 bytes_to_copy;
496         struct cx231xx_buffer *buf;
497         u32 _line_size = dev->width * 2;
498
499         if (dma_q->current_field == -1) {
500                 /* Just starting up */
501                 cx231xx_reset_vbi_buffer(dev, dma_q);
502         }
503
504         if (dma_q->current_field != field_number)
505                 dma_q->lines_completed = 0;
506
507         /* get the buffer pointer */
508         buf = dev->vbi_mode.bulk_ctl.buf;
509
510         /* Remember the field number for next time */
511         dma_q->current_field = field_number;
512
513         bytes_to_copy = dma_q->bytes_left_in_line;
514         if (bytes_to_copy > length)
515                 bytes_to_copy = length;
516
517         if (dma_q->lines_completed >= dma_q->lines_per_field) {
518                 dma_q->bytes_left_in_line -= bytes_to_copy;
519                 dma_q->is_partial_line =
520                     (dma_q->bytes_left_in_line == 0) ? 0 : 1;
521                 return 0;
522         }
523
524         dma_q->is_partial_line = 1;
525
526         /* If we don't have a buffer, just return the number of bytes we would
527            have copied if we had a buffer. */
528         if (!buf) {
529                 dma_q->bytes_left_in_line -= bytes_to_copy;
530                 dma_q->is_partial_line =
531                     (dma_q->bytes_left_in_line == 0) ? 0 : 1;
532                 return bytes_to_copy;
533         }
534
535         /* copy the data to video buffer */
536         cx231xx_do_vbi_copy(dev, dma_q, p_line, bytes_to_copy);
537
538         dma_q->pos += bytes_to_copy;
539         dma_q->bytes_left_in_line -= bytes_to_copy;
540
541         if (dma_q->bytes_left_in_line == 0) {
542
543                 dma_q->bytes_left_in_line = _line_size;
544                 dma_q->lines_completed++;
545                 dma_q->is_partial_line = 0;
546
547                 if (cx231xx_is_vbi_buffer_done(dev, dma_q) && buf) {
548
549                         vbi_buffer_filled(dev, dma_q, buf);
550
551                         dma_q->pos = 0;
552                         dma_q->lines_completed = 0;
553                         cx231xx_reset_vbi_buffer(dev, dma_q);
554                 }
555         }
556
557         return bytes_to_copy;
558 }
559
560 /*
561  * generic routine to get the next available buffer
562  */
563 static inline void get_next_vbi_buf(struct cx231xx_dmaqueue *dma_q,
564                                     struct cx231xx_buffer **buf)
565 {
566         struct cx231xx_video_mode *vmode =
567             container_of(dma_q, struct cx231xx_video_mode, vidq);
568         struct cx231xx *dev = container_of(vmode, struct cx231xx, vbi_mode);
569         char *outp;
570
571         if (list_empty(&dma_q->active)) {
572                 dev_err(dev->dev, "No active queue to serve\n");
573                 dev->vbi_mode.bulk_ctl.buf = NULL;
574                 *buf = NULL;
575                 return;
576         }
577
578         /* Get the next buffer */
579         *buf = list_entry(dma_q->active.next, struct cx231xx_buffer, list);
580
581         /* Cleans up buffer - Useful for testing for frame/URB loss */
582         outp = vb2_plane_vaddr(&(*buf)->vb.vb2_buf, 0);
583         memset(outp, 0, vb2_plane_size(&(*buf)->vb.vb2_buf, 0));
584
585         dev->vbi_mode.bulk_ctl.buf = *buf;
586
587         return;
588 }
589
590 void cx231xx_reset_vbi_buffer(struct cx231xx *dev,
591                               struct cx231xx_dmaqueue *dma_q)
592 {
593         struct cx231xx_buffer *buf;
594
595         buf = dev->vbi_mode.bulk_ctl.buf;
596
597         if (buf == NULL) {
598                 /* first try to get the buffer */
599                 get_next_vbi_buf(dma_q, &buf);
600
601                 dma_q->pos = 0;
602                 dma_q->current_field = -1;
603         }
604
605         dma_q->bytes_left_in_line = dev->width << 1;
606         dma_q->lines_completed = 0;
607 }
608
609 int cx231xx_do_vbi_copy(struct cx231xx *dev, struct cx231xx_dmaqueue *dma_q,
610                         u8 *p_buffer, u32 bytes_to_copy)
611 {
612         u8 *p_out_buffer = NULL;
613         u32 current_line_bytes_copied = 0;
614         struct cx231xx_buffer *buf;
615         u32 _line_size = dev->width << 1;
616         void *startwrite;
617         int offset, lencopy;
618
619         buf = dev->vbi_mode.bulk_ctl.buf;
620
621         if (buf == NULL)
622                 return -EINVAL;
623
624         p_out_buffer = vb2_plane_vaddr(&buf->vb.vb2_buf, 0);
625
626         if (dma_q->bytes_left_in_line != _line_size) {
627                 current_line_bytes_copied =
628                     _line_size - dma_q->bytes_left_in_line;
629         }
630
631         offset = (dma_q->lines_completed * _line_size) +
632                  current_line_bytes_copied;
633
634         if (dma_q->current_field == 2) {
635                 /* Populate the second half of the frame */
636                 offset += (dev->width * 2 * dma_q->lines_per_field);
637         }
638
639         /* prepare destination address */
640         startwrite = p_out_buffer + offset;
641
642         lencopy = dma_q->bytes_left_in_line > bytes_to_copy ?
643                   bytes_to_copy : dma_q->bytes_left_in_line;
644
645         memcpy(startwrite, p_buffer, lencopy);
646
647         return 0;
648 }
649
650 u8 cx231xx_is_vbi_buffer_done(struct cx231xx *dev,
651                               struct cx231xx_dmaqueue *dma_q)
652 {
653         u32 height = 0;
654
655         height = ((dev->norm & V4L2_STD_625_50) ?
656                   PAL_VBI_LINES : NTSC_VBI_LINES);
657         if (dma_q->lines_completed == height && dma_q->current_field == 2)
658                 return 1;
659         else
660                 return 0;
661 }