xref: /openbmc/linux/drivers/media/pci/ivtv/ivtv-irq.c (revision 861e10be)
1 /* interrupt handling
2     Copyright (C) 2003-2004  Kevin Thayer <nufan_wfk at yahoo.com>
3     Copyright (C) 2004  Chris Kennedy <c@groovy.org>
4     Copyright (C) 2005-2007  Hans Verkuil <hverkuil@xs4all.nl>
5 
6     This program is free software; you can redistribute it and/or modify
7     it under the terms of the GNU General Public License as published by
8     the Free Software Foundation; either version 2 of the License, or
9     (at your option) any later version.
10 
11     This program is distributed in the hope that it will be useful,
12     but WITHOUT ANY WARRANTY; without even the implied warranty of
13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14     GNU General Public License for more details.
15 
16     You should have received a copy of the GNU General Public License
17     along with this program; if not, write to the Free Software
18     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
19  */
20 
21 #include "ivtv-driver.h"
22 #include "ivtv-queue.h"
23 #include "ivtv-udma.h"
24 #include "ivtv-irq.h"
25 #include "ivtv-mailbox.h"
26 #include "ivtv-vbi.h"
27 #include "ivtv-yuv.h"
28 #include <media/v4l2-event.h>
29 
30 #define DMA_MAGIC_COOKIE 0x000001fe
31 
32 static void ivtv_dma_dec_start(struct ivtv_stream *s);
33 
34 static const int ivtv_stream_map[] = {
35 	IVTV_ENC_STREAM_TYPE_MPG,
36 	IVTV_ENC_STREAM_TYPE_YUV,
37 	IVTV_ENC_STREAM_TYPE_PCM,
38 	IVTV_ENC_STREAM_TYPE_VBI,
39 };
40 
41 static void ivtv_pcm_work_handler(struct ivtv *itv)
42 {
43 	struct ivtv_stream *s = &itv->streams[IVTV_ENC_STREAM_TYPE_PCM];
44 	struct ivtv_buffer *buf;
45 
46 	/* Pass the PCM data to ivtv-alsa */
47 
48 	while (1) {
49 		/*
50 		 * Users should not be using both the ALSA and V4L2 PCM audio
51 		 * capture interfaces at the same time.  If the user is doing
52 		 * this, there maybe a buffer in q_io to grab, use, and put
53 		 * back in rotation.
54 		 */
55 		buf = ivtv_dequeue(s, &s->q_io);
56 		if (buf == NULL)
57 			buf = ivtv_dequeue(s, &s->q_full);
58 		if (buf == NULL)
59 			break;
60 
61 		if (buf->readpos < buf->bytesused)
62 			itv->pcm_announce_callback(itv->alsa,
63 				(u8 *)(buf->buf + buf->readpos),
64 				(size_t)(buf->bytesused - buf->readpos));
65 
66 		ivtv_enqueue(s, buf, &s->q_free);
67 	}
68 }
69 
70 static void ivtv_pio_work_handler(struct ivtv *itv)
71 {
72 	struct ivtv_stream *s = &itv->streams[itv->cur_pio_stream];
73 	struct ivtv_buffer *buf;
74 	int i = 0;
75 
76 	IVTV_DEBUG_HI_DMA("ivtv_pio_work_handler\n");
77 	if (itv->cur_pio_stream < 0 || itv->cur_pio_stream >= IVTV_MAX_STREAMS ||
78 			s->vdev == NULL || !ivtv_use_pio(s)) {
79 		itv->cur_pio_stream = -1;
80 		/* trigger PIO complete user interrupt */
81 		write_reg(IVTV_IRQ_ENC_PIO_COMPLETE, 0x44);
82 		return;
83 	}
84 	IVTV_DEBUG_HI_DMA("Process PIO %s\n", s->name);
85 	list_for_each_entry(buf, &s->q_dma.list, list) {
86 		u32 size = s->sg_processing[i].size & 0x3ffff;
87 
88 		/* Copy the data from the card to the buffer */
89 		if (s->type == IVTV_DEC_STREAM_TYPE_VBI) {
90 			memcpy_fromio(buf->buf, itv->dec_mem + s->sg_processing[i].src - IVTV_DECODER_OFFSET, size);
91 		}
92 		else {
93 			memcpy_fromio(buf->buf, itv->enc_mem + s->sg_processing[i].src, size);
94 		}
95 		i++;
96 		if (i == s->sg_processing_size)
97 			break;
98 	}
99 	write_reg(IVTV_IRQ_ENC_PIO_COMPLETE, 0x44);
100 }
101 
102 void ivtv_irq_work_handler(struct kthread_work *work)
103 {
104 	struct ivtv *itv = container_of(work, struct ivtv, irq_work);
105 
106 	if (test_and_clear_bit(IVTV_F_I_WORK_HANDLER_PIO, &itv->i_flags))
107 		ivtv_pio_work_handler(itv);
108 
109 	if (test_and_clear_bit(IVTV_F_I_WORK_HANDLER_VBI, &itv->i_flags))
110 		ivtv_vbi_work_handler(itv);
111 
112 	if (test_and_clear_bit(IVTV_F_I_WORK_HANDLER_YUV, &itv->i_flags))
113 		ivtv_yuv_work_handler(itv);
114 
115 	if (test_and_clear_bit(IVTV_F_I_WORK_HANDLER_PCM, &itv->i_flags))
116 		ivtv_pcm_work_handler(itv);
117 }
118 
119 /* Determine the required DMA size, setup enough buffers in the predma queue and
120    actually copy the data from the card to the buffers in case a PIO transfer is
121    required for this stream.
122  */
123 static int stream_enc_dma_append(struct ivtv_stream *s, u32 data[CX2341X_MBOX_MAX_DATA])
124 {
125 	struct ivtv *itv = s->itv;
126 	struct ivtv_buffer *buf;
127 	u32 bytes_needed = 0;
128 	u32 offset, size;
129 	u32 UVoffset = 0, UVsize = 0;
130 	int skip_bufs = s->q_predma.buffers;
131 	int idx = s->sg_pending_size;
132 	int rc;
133 
134 	/* sanity checks */
135 	if (s->vdev == NULL) {
136 		IVTV_DEBUG_WARN("Stream %s not started\n", s->name);
137 		return -1;
138 	}
139 	if (!test_bit(IVTV_F_S_CLAIMED, &s->s_flags)) {
140 		IVTV_DEBUG_WARN("Stream %s not open\n", s->name);
141 		return -1;
142 	}
143 
144 	/* determine offset, size and PTS for the various streams */
145 	switch (s->type) {
146 		case IVTV_ENC_STREAM_TYPE_MPG:
147 			offset = data[1];
148 			size = data[2];
149 			s->pending_pts = 0;
150 			break;
151 
152 		case IVTV_ENC_STREAM_TYPE_YUV:
153 			offset = data[1];
154 			size = data[2];
155 			UVoffset = data[3];
156 			UVsize = data[4];
157 			s->pending_pts = ((u64) data[5] << 32) | data[6];
158 			break;
159 
160 		case IVTV_ENC_STREAM_TYPE_PCM:
161 			offset = data[1] + 12;
162 			size = data[2] - 12;
163 			s->pending_pts = read_dec(offset - 8) |
164 				((u64)(read_dec(offset - 12)) << 32);
165 			if (itv->has_cx23415)
166 				offset += IVTV_DECODER_OFFSET;
167 			break;
168 
169 		case IVTV_ENC_STREAM_TYPE_VBI:
170 			size = itv->vbi.enc_size * itv->vbi.fpi;
171 			offset = read_enc(itv->vbi.enc_start - 4) + 12;
172 			if (offset == 12) {
173 				IVTV_DEBUG_INFO("VBI offset == 0\n");
174 				return -1;
175 			}
176 			s->pending_pts = read_enc(offset - 4) | ((u64)read_enc(offset - 8) << 32);
177 			break;
178 
179 		case IVTV_DEC_STREAM_TYPE_VBI:
180 			size = read_dec(itv->vbi.dec_start + 4) + 8;
181 			offset = read_dec(itv->vbi.dec_start) + itv->vbi.dec_start;
182 			s->pending_pts = 0;
183 			offset += IVTV_DECODER_OFFSET;
184 			break;
185 		default:
186 			/* shouldn't happen */
187 			return -1;
188 	}
189 
190 	/* if this is the start of the DMA then fill in the magic cookie */
191 	if (s->sg_pending_size == 0 && ivtv_use_dma(s)) {
192 		if (itv->has_cx23415 && (s->type == IVTV_ENC_STREAM_TYPE_PCM ||
193 		    s->type == IVTV_DEC_STREAM_TYPE_VBI)) {
194 			s->pending_backup = read_dec(offset - IVTV_DECODER_OFFSET);
195 			write_dec_sync(cpu_to_le32(DMA_MAGIC_COOKIE), offset - IVTV_DECODER_OFFSET);
196 		}
197 		else {
198 			s->pending_backup = read_enc(offset);
199 			write_enc_sync(cpu_to_le32(DMA_MAGIC_COOKIE), offset);
200 		}
201 		s->pending_offset = offset;
202 	}
203 
204 	bytes_needed = size;
205 	if (s->type == IVTV_ENC_STREAM_TYPE_YUV) {
206 		/* The size for the Y samples needs to be rounded upwards to a
207 		   multiple of the buf_size. The UV samples then start in the
208 		   next buffer. */
209 		bytes_needed = s->buf_size * ((bytes_needed + s->buf_size - 1) / s->buf_size);
210 		bytes_needed += UVsize;
211 	}
212 
213 	IVTV_DEBUG_HI_DMA("%s %s: 0x%08x bytes at 0x%08x\n",
214 		ivtv_use_pio(s) ? "PIO" : "DMA", s->name, bytes_needed, offset);
215 
216 	rc = ivtv_queue_move(s, &s->q_free, &s->q_full, &s->q_predma, bytes_needed);
217 	if (rc < 0) { /* Insufficient buffers */
218 		IVTV_DEBUG_WARN("Cannot obtain %d bytes for %s data transfer\n",
219 				bytes_needed, s->name);
220 		return -1;
221 	}
222 	if (rc && !s->buffers_stolen && test_bit(IVTV_F_S_APPL_IO, &s->s_flags)) {
223 		IVTV_WARN("All %s stream buffers are full. Dropping data.\n", s->name);
224 		IVTV_WARN("Cause: the application is not reading fast enough.\n");
225 	}
226 	s->buffers_stolen = rc;
227 
228 	/* got the buffers, now fill in sg_pending */
229 	buf = list_entry(s->q_predma.list.next, struct ivtv_buffer, list);
230 	memset(buf->buf, 0, 128);
231 	list_for_each_entry(buf, &s->q_predma.list, list) {
232 		if (skip_bufs-- > 0)
233 			continue;
234 		s->sg_pending[idx].dst = buf->dma_handle;
235 		s->sg_pending[idx].src = offset;
236 		s->sg_pending[idx].size = s->buf_size;
237 		buf->bytesused = min(size, s->buf_size);
238 		buf->dma_xfer_cnt = s->dma_xfer_cnt;
239 
240 		s->q_predma.bytesused += buf->bytesused;
241 		size -= buf->bytesused;
242 		offset += s->buf_size;
243 
244 		/* Sync SG buffers */
245 		ivtv_buf_sync_for_device(s, buf);
246 
247 		if (size == 0) {	/* YUV */
248 			/* process the UV section */
249 			offset = UVoffset;
250 			size = UVsize;
251 		}
252 		idx++;
253 	}
254 	s->sg_pending_size = idx;
255 	return 0;
256 }
257 
258 static void dma_post(struct ivtv_stream *s)
259 {
260 	struct ivtv *itv = s->itv;
261 	struct ivtv_buffer *buf = NULL;
262 	struct list_head *p;
263 	u32 offset;
264 	__le32 *u32buf;
265 	int x = 0;
266 
267 	IVTV_DEBUG_HI_DMA("%s %s completed (%x)\n", ivtv_use_pio(s) ? "PIO" : "DMA",
268 			s->name, s->dma_offset);
269 	list_for_each(p, &s->q_dma.list) {
270 		buf = list_entry(p, struct ivtv_buffer, list);
271 		u32buf = (__le32 *)buf->buf;
272 
273 		/* Sync Buffer */
274 		ivtv_buf_sync_for_cpu(s, buf);
275 
276 		if (x == 0 && ivtv_use_dma(s)) {
277 			offset = s->dma_last_offset;
278 			if (u32buf[offset / 4] != DMA_MAGIC_COOKIE)
279 			{
280 				for (offset = 0; offset < 64; offset++) {
281 					if (u32buf[offset] == DMA_MAGIC_COOKIE) {
282 						break;
283 					}
284 				}
285 				offset *= 4;
286 				if (offset == 256) {
287 					IVTV_DEBUG_WARN("%s: Couldn't find start of buffer within the first 256 bytes\n", s->name);
288 					offset = s->dma_last_offset;
289 				}
290 				if (s->dma_last_offset != offset)
291 					IVTV_DEBUG_WARN("%s: offset %d -> %d\n", s->name, s->dma_last_offset, offset);
292 				s->dma_last_offset = offset;
293 			}
294 			if (itv->has_cx23415 && (s->type == IVTV_ENC_STREAM_TYPE_PCM ||
295 						s->type == IVTV_DEC_STREAM_TYPE_VBI)) {
296 				write_dec_sync(0, s->dma_offset - IVTV_DECODER_OFFSET);
297 			}
298 			else {
299 				write_enc_sync(0, s->dma_offset);
300 			}
301 			if (offset) {
302 				buf->bytesused -= offset;
303 				memcpy(buf->buf, buf->buf + offset, buf->bytesused + offset);
304 			}
305 			*u32buf = cpu_to_le32(s->dma_backup);
306 		}
307 		x++;
308 		/* flag byteswap ABCD -> DCBA for MPG & VBI data outside irq */
309 		if (s->type == IVTV_ENC_STREAM_TYPE_MPG ||
310 		    s->type == IVTV_ENC_STREAM_TYPE_VBI)
311 			buf->b_flags |= IVTV_F_B_NEED_BUF_SWAP;
312 	}
313 	if (buf)
314 		buf->bytesused += s->dma_last_offset;
315 	if (buf && s->type == IVTV_DEC_STREAM_TYPE_VBI) {
316 		list_for_each_entry(buf, &s->q_dma.list, list) {
317 			/* Parse and Groom VBI Data */
318 			s->q_dma.bytesused -= buf->bytesused;
319 			ivtv_process_vbi_data(itv, buf, 0, s->type);
320 			s->q_dma.bytesused += buf->bytesused;
321 		}
322 		if (s->fh == NULL) {
323 			ivtv_queue_move(s, &s->q_dma, NULL, &s->q_free, 0);
324 			return;
325 		}
326 	}
327 
328 	ivtv_queue_move(s, &s->q_dma, NULL, &s->q_full, s->q_dma.bytesused);
329 
330 	if (s->type == IVTV_ENC_STREAM_TYPE_PCM &&
331 	    itv->pcm_announce_callback != NULL) {
332 		/*
333 		 * Set up the work handler to pass the data to ivtv-alsa.
334 		 *
335 		 * We just use q_full and let the work handler race with users
336 		 * making ivtv-fileops.c calls on the PCM device node.
337 		 *
338 		 * Users should not be using both the ALSA and V4L2 PCM audio
339 		 * capture interfaces at the same time.  If the user does this,
340 		 * fragments of data will just go out each interface as they
341 		 * race for PCM data.
342 		 */
343 		set_bit(IVTV_F_I_WORK_HANDLER_PCM, &itv->i_flags);
344 		set_bit(IVTV_F_I_HAVE_WORK, &itv->i_flags);
345 	}
346 
347 	if (s->fh)
348 		wake_up(&s->waitq);
349 }
350 
351 void ivtv_dma_stream_dec_prepare(struct ivtv_stream *s, u32 offset, int lock)
352 {
353 	struct ivtv *itv = s->itv;
354 	struct yuv_playback_info *yi = &itv->yuv_info;
355 	u8 frame = yi->draw_frame;
356 	struct yuv_frame_info *f = &yi->new_frame_info[frame];
357 	struct ivtv_buffer *buf;
358 	u32 y_size = 720 * ((f->src_h + 31) & ~31);
359 	u32 uv_offset = offset + IVTV_YUV_BUFFER_UV_OFFSET;
360 	int y_done = 0;
361 	int bytes_written = 0;
362 	unsigned long flags = 0;
363 	int idx = 0;
364 
365 	IVTV_DEBUG_HI_DMA("DEC PREPARE DMA %s: %08x %08x\n", s->name, s->q_predma.bytesused, offset);
366 
367 	/* Insert buffer block for YUV if needed */
368 	if (s->type == IVTV_DEC_STREAM_TYPE_YUV && f->offset_y) {
369 		if (yi->blanking_dmaptr) {
370 			s->sg_pending[idx].src = yi->blanking_dmaptr;
371 			s->sg_pending[idx].dst = offset;
372 			s->sg_pending[idx].size = 720 * 16;
373 		}
374 		offset += 720 * 16;
375 		idx++;
376 	}
377 
378 	list_for_each_entry(buf, &s->q_predma.list, list) {
379 		/* YUV UV Offset from Y Buffer */
380 		if (s->type == IVTV_DEC_STREAM_TYPE_YUV && !y_done &&
381 				(bytes_written + buf->bytesused) >= y_size) {
382 			s->sg_pending[idx].src = buf->dma_handle;
383 			s->sg_pending[idx].dst = offset;
384 			s->sg_pending[idx].size = y_size - bytes_written;
385 			offset = uv_offset;
386 			if (s->sg_pending[idx].size != buf->bytesused) {
387 				idx++;
388 				s->sg_pending[idx].src =
389 				  buf->dma_handle + s->sg_pending[idx - 1].size;
390 				s->sg_pending[idx].dst = offset;
391 				s->sg_pending[idx].size =
392 				   buf->bytesused - s->sg_pending[idx - 1].size;
393 				offset += s->sg_pending[idx].size;
394 			}
395 			y_done = 1;
396 		} else {
397 			s->sg_pending[idx].src = buf->dma_handle;
398 			s->sg_pending[idx].dst = offset;
399 			s->sg_pending[idx].size = buf->bytesused;
400 			offset += buf->bytesused;
401 		}
402 		bytes_written += buf->bytesused;
403 
404 		/* Sync SG buffers */
405 		ivtv_buf_sync_for_device(s, buf);
406 		idx++;
407 	}
408 	s->sg_pending_size = idx;
409 
410 	/* Sync Hardware SG List of buffers */
411 	ivtv_stream_sync_for_device(s);
412 	if (lock)
413 		spin_lock_irqsave(&itv->dma_reg_lock, flags);
414 	if (!test_bit(IVTV_F_I_DMA, &itv->i_flags)) {
415 		ivtv_dma_dec_start(s);
416 	}
417 	else {
418 		set_bit(IVTV_F_S_DMA_PENDING, &s->s_flags);
419 	}
420 	if (lock)
421 		spin_unlock_irqrestore(&itv->dma_reg_lock, flags);
422 }
423 
424 static void ivtv_dma_enc_start_xfer(struct ivtv_stream *s)
425 {
426 	struct ivtv *itv = s->itv;
427 
428 	s->sg_dma->src = cpu_to_le32(s->sg_processing[s->sg_processed].src);
429 	s->sg_dma->dst = cpu_to_le32(s->sg_processing[s->sg_processed].dst);
430 	s->sg_dma->size = cpu_to_le32(s->sg_processing[s->sg_processed].size | 0x80000000);
431 	s->sg_processed++;
432 	/* Sync Hardware SG List of buffers */
433 	ivtv_stream_sync_for_device(s);
434 	write_reg(s->sg_handle, IVTV_REG_ENCDMAADDR);
435 	write_reg_sync(read_reg(IVTV_REG_DMAXFER) | 0x02, IVTV_REG_DMAXFER);
436 	itv->dma_timer.expires = jiffies + msecs_to_jiffies(300);
437 	add_timer(&itv->dma_timer);
438 }
439 
440 static void ivtv_dma_dec_start_xfer(struct ivtv_stream *s)
441 {
442 	struct ivtv *itv = s->itv;
443 
444 	s->sg_dma->src = cpu_to_le32(s->sg_processing[s->sg_processed].src);
445 	s->sg_dma->dst = cpu_to_le32(s->sg_processing[s->sg_processed].dst);
446 	s->sg_dma->size = cpu_to_le32(s->sg_processing[s->sg_processed].size | 0x80000000);
447 	s->sg_processed++;
448 	/* Sync Hardware SG List of buffers */
449 	ivtv_stream_sync_for_device(s);
450 	write_reg(s->sg_handle, IVTV_REG_DECDMAADDR);
451 	write_reg_sync(read_reg(IVTV_REG_DMAXFER) | 0x01, IVTV_REG_DMAXFER);
452 	itv->dma_timer.expires = jiffies + msecs_to_jiffies(300);
453 	add_timer(&itv->dma_timer);
454 }
455 
456 /* start the encoder DMA */
457 static void ivtv_dma_enc_start(struct ivtv_stream *s)
458 {
459 	struct ivtv *itv = s->itv;
460 	struct ivtv_stream *s_vbi = &itv->streams[IVTV_ENC_STREAM_TYPE_VBI];
461 	int i;
462 
463 	IVTV_DEBUG_HI_DMA("start %s for %s\n", ivtv_use_dma(s) ? "DMA" : "PIO", s->name);
464 
465 	if (s->q_predma.bytesused)
466 		ivtv_queue_move(s, &s->q_predma, NULL, &s->q_dma, s->q_predma.bytesused);
467 
468 	if (ivtv_use_dma(s))
469 		s->sg_pending[s->sg_pending_size - 1].size += 256;
470 
471 	/* If this is an MPEG stream, and VBI data is also pending, then append the
472 	   VBI DMA to the MPEG DMA and transfer both sets of data at once.
473 
474 	   VBI DMA is a second class citizen compared to MPEG and mixing them together
475 	   will confuse the firmware (the end of a VBI DMA is seen as the end of a
476 	   MPEG DMA, thus effectively dropping an MPEG frame). So instead we make
477 	   sure we only use the MPEG DMA to transfer the VBI DMA if both are in
478 	   use. This way no conflicts occur. */
479 	clear_bit(IVTV_F_S_DMA_HAS_VBI, &s->s_flags);
480 	if (s->type == IVTV_ENC_STREAM_TYPE_MPG && s_vbi->sg_pending_size &&
481 			s->sg_pending_size + s_vbi->sg_pending_size <= s->buffers) {
482 		ivtv_queue_move(s_vbi, &s_vbi->q_predma, NULL, &s_vbi->q_dma, s_vbi->q_predma.bytesused);
483 		if (ivtv_use_dma(s_vbi))
484 			s_vbi->sg_pending[s_vbi->sg_pending_size - 1].size += 256;
485 		for (i = 0; i < s_vbi->sg_pending_size; i++) {
486 			s->sg_pending[s->sg_pending_size++] = s_vbi->sg_pending[i];
487 		}
488 		s_vbi->dma_offset = s_vbi->pending_offset;
489 		s_vbi->sg_pending_size = 0;
490 		s_vbi->dma_xfer_cnt++;
491 		set_bit(IVTV_F_S_DMA_HAS_VBI, &s->s_flags);
492 		IVTV_DEBUG_HI_DMA("include DMA for %s\n", s_vbi->name);
493 	}
494 
495 	s->dma_xfer_cnt++;
496 	memcpy(s->sg_processing, s->sg_pending, sizeof(struct ivtv_sg_host_element) * s->sg_pending_size);
497 	s->sg_processing_size = s->sg_pending_size;
498 	s->sg_pending_size = 0;
499 	s->sg_processed = 0;
500 	s->dma_offset = s->pending_offset;
501 	s->dma_backup = s->pending_backup;
502 	s->dma_pts = s->pending_pts;
503 
504 	if (ivtv_use_pio(s)) {
505 		set_bit(IVTV_F_I_WORK_HANDLER_PIO, &itv->i_flags);
506 		set_bit(IVTV_F_I_HAVE_WORK, &itv->i_flags);
507 		set_bit(IVTV_F_I_PIO, &itv->i_flags);
508 		itv->cur_pio_stream = s->type;
509 	}
510 	else {
511 		itv->dma_retries = 0;
512 		ivtv_dma_enc_start_xfer(s);
513 		set_bit(IVTV_F_I_DMA, &itv->i_flags);
514 		itv->cur_dma_stream = s->type;
515 	}
516 }
517 
518 static void ivtv_dma_dec_start(struct ivtv_stream *s)
519 {
520 	struct ivtv *itv = s->itv;
521 
522 	if (s->q_predma.bytesused)
523 		ivtv_queue_move(s, &s->q_predma, NULL, &s->q_dma, s->q_predma.bytesused);
524 	s->dma_xfer_cnt++;
525 	memcpy(s->sg_processing, s->sg_pending, sizeof(struct ivtv_sg_host_element) * s->sg_pending_size);
526 	s->sg_processing_size = s->sg_pending_size;
527 	s->sg_pending_size = 0;
528 	s->sg_processed = 0;
529 
530 	IVTV_DEBUG_HI_DMA("start DMA for %s\n", s->name);
531 	itv->dma_retries = 0;
532 	ivtv_dma_dec_start_xfer(s);
533 	set_bit(IVTV_F_I_DMA, &itv->i_flags);
534 	itv->cur_dma_stream = s->type;
535 }
536 
537 static void ivtv_irq_dma_read(struct ivtv *itv)
538 {
539 	struct ivtv_stream *s = NULL;
540 	struct ivtv_buffer *buf;
541 	int hw_stream_type = 0;
542 
543 	IVTV_DEBUG_HI_IRQ("DEC DMA READ\n");
544 
545 	del_timer(&itv->dma_timer);
546 
547 	if (!test_bit(IVTV_F_I_UDMA, &itv->i_flags) && itv->cur_dma_stream < 0)
548 		return;
549 
550 	if (!test_bit(IVTV_F_I_UDMA, &itv->i_flags)) {
551 		s = &itv->streams[itv->cur_dma_stream];
552 		ivtv_stream_sync_for_cpu(s);
553 
554 		if (read_reg(IVTV_REG_DMASTATUS) & 0x14) {
555 			IVTV_DEBUG_WARN("DEC DMA ERROR %x (xfer %d of %d, retry %d)\n",
556 					read_reg(IVTV_REG_DMASTATUS),
557 					s->sg_processed, s->sg_processing_size, itv->dma_retries);
558 			write_reg(read_reg(IVTV_REG_DMASTATUS) & 3, IVTV_REG_DMASTATUS);
559 			if (itv->dma_retries == 3) {
560 				/* Too many retries, give up on this frame */
561 				itv->dma_retries = 0;
562 				s->sg_processed = s->sg_processing_size;
563 			}
564 			else {
565 				/* Retry, starting with the first xfer segment.
566 				   Just retrying the current segment is not sufficient. */
567 				s->sg_processed = 0;
568 				itv->dma_retries++;
569 			}
570 		}
571 		if (s->sg_processed < s->sg_processing_size) {
572 			/* DMA next buffer */
573 			ivtv_dma_dec_start_xfer(s);
574 			return;
575 		}
576 		if (s->type == IVTV_DEC_STREAM_TYPE_YUV)
577 			hw_stream_type = 2;
578 		IVTV_DEBUG_HI_DMA("DEC DATA READ %s: %d\n", s->name, s->q_dma.bytesused);
579 
580 		/* For some reason must kick the firmware, like PIO mode,
581 		   I think this tells the firmware we are done and the size
582 		   of the xfer so it can calculate what we need next.
583 		   I think we can do this part ourselves but would have to
584 		   fully calculate xfer info ourselves and not use interrupts
585 		 */
586 		ivtv_vapi(itv, CX2341X_DEC_SCHED_DMA_FROM_HOST, 3, 0, s->q_dma.bytesused,
587 				hw_stream_type);
588 
589 		/* Free last DMA call */
590 		while ((buf = ivtv_dequeue(s, &s->q_dma)) != NULL) {
591 			ivtv_buf_sync_for_cpu(s, buf);
592 			ivtv_enqueue(s, buf, &s->q_free);
593 		}
594 		wake_up(&s->waitq);
595 	}
596 	clear_bit(IVTV_F_I_UDMA, &itv->i_flags);
597 	clear_bit(IVTV_F_I_DMA, &itv->i_flags);
598 	itv->cur_dma_stream = -1;
599 	wake_up(&itv->dma_waitq);
600 }
601 
602 static void ivtv_irq_enc_dma_complete(struct ivtv *itv)
603 {
604 	u32 data[CX2341X_MBOX_MAX_DATA];
605 	struct ivtv_stream *s;
606 
607 	ivtv_api_get_data(&itv->enc_mbox, IVTV_MBOX_DMA_END, 2, data);
608 	IVTV_DEBUG_HI_IRQ("ENC DMA COMPLETE %x %d (%d)\n", data[0], data[1], itv->cur_dma_stream);
609 
610 	del_timer(&itv->dma_timer);
611 
612 	if (itv->cur_dma_stream < 0)
613 		return;
614 
615 	s = &itv->streams[itv->cur_dma_stream];
616 	ivtv_stream_sync_for_cpu(s);
617 
618 	if (data[0] & 0x18) {
619 		IVTV_DEBUG_WARN("ENC DMA ERROR %x (offset %08x, xfer %d of %d, retry %d)\n", data[0],
620 			s->dma_offset, s->sg_processed, s->sg_processing_size, itv->dma_retries);
621 		write_reg(read_reg(IVTV_REG_DMASTATUS) & 3, IVTV_REG_DMASTATUS);
622 		if (itv->dma_retries == 3) {
623 			/* Too many retries, give up on this frame */
624 			itv->dma_retries = 0;
625 			s->sg_processed = s->sg_processing_size;
626 		}
627 		else {
628 			/* Retry, starting with the first xfer segment.
629 			   Just retrying the current segment is not sufficient. */
630 			s->sg_processed = 0;
631 			itv->dma_retries++;
632 		}
633 	}
634 	if (s->sg_processed < s->sg_processing_size) {
635 		/* DMA next buffer */
636 		ivtv_dma_enc_start_xfer(s);
637 		return;
638 	}
639 	clear_bit(IVTV_F_I_DMA, &itv->i_flags);
640 	itv->cur_dma_stream = -1;
641 	dma_post(s);
642 	if (test_and_clear_bit(IVTV_F_S_DMA_HAS_VBI, &s->s_flags)) {
643 		s = &itv->streams[IVTV_ENC_STREAM_TYPE_VBI];
644 		dma_post(s);
645 	}
646 	s->sg_processing_size = 0;
647 	s->sg_processed = 0;
648 	wake_up(&itv->dma_waitq);
649 }
650 
651 static void ivtv_irq_enc_pio_complete(struct ivtv *itv)
652 {
653 	struct ivtv_stream *s;
654 
655 	if (itv->cur_pio_stream < 0 || itv->cur_pio_stream >= IVTV_MAX_STREAMS) {
656 		itv->cur_pio_stream = -1;
657 		return;
658 	}
659 	s = &itv->streams[itv->cur_pio_stream];
660 	IVTV_DEBUG_HI_IRQ("ENC PIO COMPLETE %s\n", s->name);
661 	clear_bit(IVTV_F_I_PIO, &itv->i_flags);
662 	itv->cur_pio_stream = -1;
663 	dma_post(s);
664 	if (s->type == IVTV_ENC_STREAM_TYPE_MPG)
665 		ivtv_vapi(itv, CX2341X_ENC_SCHED_DMA_TO_HOST, 3, 0, 0, 0);
666 	else if (s->type == IVTV_ENC_STREAM_TYPE_YUV)
667 		ivtv_vapi(itv, CX2341X_ENC_SCHED_DMA_TO_HOST, 3, 0, 0, 1);
668 	else if (s->type == IVTV_ENC_STREAM_TYPE_PCM)
669 		ivtv_vapi(itv, CX2341X_ENC_SCHED_DMA_TO_HOST, 3, 0, 0, 2);
670 	clear_bit(IVTV_F_I_PIO, &itv->i_flags);
671 	if (test_and_clear_bit(IVTV_F_S_DMA_HAS_VBI, &s->s_flags)) {
672 		s = &itv->streams[IVTV_ENC_STREAM_TYPE_VBI];
673 		dma_post(s);
674 	}
675 	wake_up(&itv->dma_waitq);
676 }
677 
678 static void ivtv_irq_dma_err(struct ivtv *itv)
679 {
680 	u32 data[CX2341X_MBOX_MAX_DATA];
681 	u32 status;
682 
683 	del_timer(&itv->dma_timer);
684 
685 	ivtv_api_get_data(&itv->enc_mbox, IVTV_MBOX_DMA_END, 2, data);
686 	status = read_reg(IVTV_REG_DMASTATUS);
687 	IVTV_DEBUG_WARN("DMA ERROR %08x %08x %08x %d\n", data[0], data[1],
688 				status, itv->cur_dma_stream);
689 	/*
690 	 * We do *not* write back to the IVTV_REG_DMASTATUS register to
691 	 * clear the error status, if either the encoder write (0x02) or
692 	 * decoder read (0x01) bus master DMA operation do not indicate
693 	 * completed.  We can race with the DMA engine, which may have
694 	 * transitioned to completed status *after* we read the register.
695 	 * Setting a IVTV_REG_DMASTATUS flag back to "busy" status, after the
696 	 * DMA engine has completed, will cause the DMA engine to stop working.
697 	 */
698 	status &= 0x3;
699 	if (status == 0x3)
700 		write_reg(status, IVTV_REG_DMASTATUS);
701 
702 	if (!test_bit(IVTV_F_I_UDMA, &itv->i_flags) &&
703 	    itv->cur_dma_stream >= 0 && itv->cur_dma_stream < IVTV_MAX_STREAMS) {
704 		struct ivtv_stream *s = &itv->streams[itv->cur_dma_stream];
705 
706 		if (s->type >= IVTV_DEC_STREAM_TYPE_MPG) {
707 			/* retry */
708 			/*
709 			 * FIXME - handle cases of DMA error similar to
710 			 * encoder below, except conditioned on status & 0x1
711 			 */
712 			ivtv_dma_dec_start(s);
713 			return;
714 		} else {
715 			if ((status & 0x2) == 0) {
716 				/*
717 				 * CX2341x Bus Master DMA write is ongoing.
718 				 * Reset the timer and let it complete.
719 				 */
720 				itv->dma_timer.expires =
721 						jiffies + msecs_to_jiffies(600);
722 				add_timer(&itv->dma_timer);
723 				return;
724 			}
725 
726 			if (itv->dma_retries < 3) {
727 				/*
728 				 * CX2341x Bus Master DMA write has ended.
729 				 * Retry the write, starting with the first
730 				 * xfer segment. Just retrying the current
731 				 * segment is not sufficient.
732 				 */
733 				s->sg_processed = 0;
734 				itv->dma_retries++;
735 				ivtv_dma_enc_start_xfer(s);
736 				return;
737 			}
738 			/* Too many retries, give up on this one */
739 		}
740 
741 	}
742 	if (test_bit(IVTV_F_I_UDMA, &itv->i_flags)) {
743 		ivtv_udma_start(itv);
744 		return;
745 	}
746 	clear_bit(IVTV_F_I_UDMA, &itv->i_flags);
747 	clear_bit(IVTV_F_I_DMA, &itv->i_flags);
748 	itv->cur_dma_stream = -1;
749 	wake_up(&itv->dma_waitq);
750 }
751 
752 static void ivtv_irq_enc_start_cap(struct ivtv *itv)
753 {
754 	u32 data[CX2341X_MBOX_MAX_DATA];
755 	struct ivtv_stream *s;
756 
757 	/* Get DMA destination and size arguments from card */
758 	ivtv_api_get_data(&itv->enc_mbox, IVTV_MBOX_DMA, 7, data);
759 	IVTV_DEBUG_HI_IRQ("ENC START CAP %d: %08x %08x\n", data[0], data[1], data[2]);
760 
761 	if (data[0] > 2 || data[1] == 0 || data[2] == 0) {
762 		IVTV_DEBUG_WARN("Unknown input: %08x %08x %08x\n",
763 				data[0], data[1], data[2]);
764 		return;
765 	}
766 	s = &itv->streams[ivtv_stream_map[data[0]]];
767 	if (!stream_enc_dma_append(s, data)) {
768 		set_bit(ivtv_use_pio(s) ? IVTV_F_S_PIO_PENDING : IVTV_F_S_DMA_PENDING, &s->s_flags);
769 	}
770 }
771 
772 static void ivtv_irq_enc_vbi_cap(struct ivtv *itv)
773 {
774 	u32 data[CX2341X_MBOX_MAX_DATA];
775 	struct ivtv_stream *s;
776 
777 	IVTV_DEBUG_HI_IRQ("ENC START VBI CAP\n");
778 	s = &itv->streams[IVTV_ENC_STREAM_TYPE_VBI];
779 
780 	if (!stream_enc_dma_append(s, data))
781 		set_bit(ivtv_use_pio(s) ? IVTV_F_S_PIO_PENDING : IVTV_F_S_DMA_PENDING, &s->s_flags);
782 }
783 
784 static void ivtv_irq_dec_vbi_reinsert(struct ivtv *itv)
785 {
786 	u32 data[CX2341X_MBOX_MAX_DATA];
787 	struct ivtv_stream *s = &itv->streams[IVTV_DEC_STREAM_TYPE_VBI];
788 
789 	IVTV_DEBUG_HI_IRQ("DEC VBI REINSERT\n");
790 	if (test_bit(IVTV_F_S_CLAIMED, &s->s_flags) &&
791 			!stream_enc_dma_append(s, data)) {
792 		set_bit(IVTV_F_S_PIO_PENDING, &s->s_flags);
793 	}
794 }
795 
796 static void ivtv_irq_dec_data_req(struct ivtv *itv)
797 {
798 	u32 data[CX2341X_MBOX_MAX_DATA];
799 	struct ivtv_stream *s;
800 
801 	/* YUV or MPG */
802 
803 	if (test_bit(IVTV_F_I_DEC_YUV, &itv->i_flags)) {
804 		ivtv_api_get_data(&itv->dec_mbox, IVTV_MBOX_DMA, 2, data);
805 		itv->dma_data_req_size =
806 				 1080 * ((itv->yuv_info.v4l2_src_h + 31) & ~31);
807 		itv->dma_data_req_offset = data[1];
808 		if (atomic_read(&itv->yuv_info.next_dma_frame) >= 0)
809 			ivtv_yuv_frame_complete(itv);
810 		s = &itv->streams[IVTV_DEC_STREAM_TYPE_YUV];
811 	}
812 	else {
813 		ivtv_api_get_data(&itv->dec_mbox, IVTV_MBOX_DMA, 3, data);
814 		itv->dma_data_req_size = min_t(u32, data[2], 0x10000);
815 		itv->dma_data_req_offset = data[1];
816 		s = &itv->streams[IVTV_DEC_STREAM_TYPE_MPG];
817 	}
818 	IVTV_DEBUG_HI_IRQ("DEC DATA REQ %s: %d %08x %u\n", s->name, s->q_full.bytesused,
819 		       itv->dma_data_req_offset, itv->dma_data_req_size);
820 	if (itv->dma_data_req_size == 0 || s->q_full.bytesused < itv->dma_data_req_size) {
821 		set_bit(IVTV_F_S_NEEDS_DATA, &s->s_flags);
822 	}
823 	else {
824 		if (test_bit(IVTV_F_I_DEC_YUV, &itv->i_flags))
825 			ivtv_yuv_setup_stream_frame(itv);
826 		clear_bit(IVTV_F_S_NEEDS_DATA, &s->s_flags);
827 		ivtv_queue_move(s, &s->q_full, NULL, &s->q_predma, itv->dma_data_req_size);
828 		ivtv_dma_stream_dec_prepare(s, itv->dma_data_req_offset + IVTV_DECODER_OFFSET, 0);
829 	}
830 }
831 
832 static void ivtv_irq_vsync(struct ivtv *itv)
833 {
834 	/* The vsync interrupt is unusual in that it won't clear until
835 	 * the end of the first line for the current field, at which
836 	 * point it clears itself. This can result in repeated vsync
837 	 * interrupts, or a missed vsync. Read some of the registers
838 	 * to determine the line being displayed and ensure we handle
839 	 * one vsync per frame.
840 	 */
841 	unsigned int frame = read_reg(IVTV_REG_DEC_LINE_FIELD) & 1;
842 	struct yuv_playback_info *yi = &itv->yuv_info;
843 	int last_dma_frame = atomic_read(&yi->next_dma_frame);
844 	struct yuv_frame_info *f = &yi->new_frame_info[last_dma_frame];
845 
846 	if (0) IVTV_DEBUG_IRQ("DEC VSYNC\n");
847 
848 	if (((frame ^ f->sync_field) == 0 &&
849 		((itv->last_vsync_field & 1) ^ f->sync_field)) ||
850 			(frame != (itv->last_vsync_field & 1) && !f->interlaced)) {
851 		int next_dma_frame = last_dma_frame;
852 
853 		if (!(f->interlaced && f->delay && yi->fields_lapsed < 1)) {
854 			if (next_dma_frame >= 0 && next_dma_frame != atomic_read(&yi->next_fill_frame)) {
855 				write_reg(yuv_offset[next_dma_frame] >> 4, 0x82c);
856 				write_reg((yuv_offset[next_dma_frame] + IVTV_YUV_BUFFER_UV_OFFSET) >> 4, 0x830);
857 				write_reg(yuv_offset[next_dma_frame] >> 4, 0x834);
858 				write_reg((yuv_offset[next_dma_frame] + IVTV_YUV_BUFFER_UV_OFFSET) >> 4, 0x838);
859 				next_dma_frame = (next_dma_frame + 1) % IVTV_YUV_BUFFERS;
860 				atomic_set(&yi->next_dma_frame, next_dma_frame);
861 				yi->fields_lapsed = -1;
862 				yi->running = 1;
863 			}
864 		}
865 	}
866 	if (frame != (itv->last_vsync_field & 1)) {
867 		static const struct v4l2_event evtop = {
868 			.type = V4L2_EVENT_VSYNC,
869 			.u.vsync.field = V4L2_FIELD_TOP,
870 		};
871 		static const struct v4l2_event evbottom = {
872 			.type = V4L2_EVENT_VSYNC,
873 			.u.vsync.field = V4L2_FIELD_BOTTOM,
874 		};
875 		struct ivtv_stream *s = ivtv_get_output_stream(itv);
876 
877 		itv->last_vsync_field += 1;
878 		if (frame == 0) {
879 			clear_bit(IVTV_F_I_VALID_DEC_TIMINGS, &itv->i_flags);
880 			clear_bit(IVTV_F_I_EV_VSYNC_FIELD, &itv->i_flags);
881 		}
882 		else {
883 			set_bit(IVTV_F_I_EV_VSYNC_FIELD, &itv->i_flags);
884 		}
885 		if (test_bit(IVTV_F_I_EV_VSYNC_ENABLED, &itv->i_flags)) {
886 			set_bit(IVTV_F_I_EV_VSYNC, &itv->i_flags);
887 			wake_up(&itv->event_waitq);
888 			if (s)
889 				wake_up(&s->waitq);
890 		}
891 		if (s && s->vdev)
892 			v4l2_event_queue(s->vdev, frame ? &evtop : &evbottom);
893 		wake_up(&itv->vsync_waitq);
894 
895 		/* Send VBI to saa7127 */
896 		if (frame && (itv->output_mode == OUT_PASSTHROUGH ||
897 			test_bit(IVTV_F_I_UPDATE_WSS, &itv->i_flags) ||
898 			test_bit(IVTV_F_I_UPDATE_VPS, &itv->i_flags) ||
899 			test_bit(IVTV_F_I_UPDATE_CC, &itv->i_flags))) {
900 			set_bit(IVTV_F_I_WORK_HANDLER_VBI, &itv->i_flags);
901 			set_bit(IVTV_F_I_HAVE_WORK, &itv->i_flags);
902 		}
903 
904 		/* Check if we need to update the yuv registers */
905 		if (yi->running && (yi->yuv_forced_update || f->update)) {
906 			if (!f->update) {
907 				last_dma_frame =
908 					(u8)(atomic_read(&yi->next_dma_frame) -
909 						 1) % IVTV_YUV_BUFFERS;
910 				f = &yi->new_frame_info[last_dma_frame];
911 			}
912 
913 			if (f->src_w) {
914 				yi->update_frame = last_dma_frame;
915 				f->update = 0;
916 				yi->yuv_forced_update = 0;
917 				set_bit(IVTV_F_I_WORK_HANDLER_YUV, &itv->i_flags);
918 				set_bit(IVTV_F_I_HAVE_WORK, &itv->i_flags);
919 			}
920 		}
921 
922 		yi->fields_lapsed++;
923 	}
924 }
925 
926 #define IVTV_IRQ_DMA (IVTV_IRQ_DMA_READ | IVTV_IRQ_ENC_DMA_COMPLETE | IVTV_IRQ_DMA_ERR | IVTV_IRQ_ENC_START_CAP | IVTV_IRQ_ENC_VBI_CAP | IVTV_IRQ_DEC_DATA_REQ | IVTV_IRQ_DEC_VBI_RE_INSERT)
927 
928 irqreturn_t ivtv_irq_handler(int irq, void *dev_id)
929 {
930 	struct ivtv *itv = (struct ivtv *)dev_id;
931 	u32 combo;
932 	u32 stat;
933 	int i;
934 	u8 vsync_force = 0;
935 
936 	spin_lock(&itv->dma_reg_lock);
937 	/* get contents of irq status register */
938 	stat = read_reg(IVTV_REG_IRQSTATUS);
939 
940 	combo = ~itv->irqmask & stat;
941 
942 	/* Clear out IRQ */
943 	if (combo) write_reg(combo, IVTV_REG_IRQSTATUS);
944 
945 	if (0 == combo) {
946 		/* The vsync interrupt is unusual and clears itself. If we
947 		 * took too long, we may have missed it. Do some checks
948 		 */
949 		if (~itv->irqmask & IVTV_IRQ_DEC_VSYNC) {
950 			/* vsync is enabled, see if we're in a new field */
951 			if ((itv->last_vsync_field & 1) !=
952 			    (read_reg(IVTV_REG_DEC_LINE_FIELD) & 1)) {
953 				/* New field, looks like we missed it */
954 				IVTV_DEBUG_YUV("VSync interrupt missed %d\n",
955 				       read_reg(IVTV_REG_DEC_LINE_FIELD) >> 16);
956 				vsync_force = 1;
957 			}
958 		}
959 
960 		if (!vsync_force) {
961 			/* No Vsync expected, wasn't for us */
962 			spin_unlock(&itv->dma_reg_lock);
963 			return IRQ_NONE;
964 		}
965 	}
966 
967 	/* Exclude interrupts noted below from the output, otherwise the log is flooded with
968 	   these messages */
969 	if (combo & ~0xff6d0400)
970 		IVTV_DEBUG_HI_IRQ("======= valid IRQ bits: 0x%08x ======\n", combo);
971 
972 	if (combo & IVTV_IRQ_DEC_DMA_COMPLETE) {
973 		IVTV_DEBUG_HI_IRQ("DEC DMA COMPLETE\n");
974 	}
975 
976 	if (combo & IVTV_IRQ_DMA_READ) {
977 		ivtv_irq_dma_read(itv);
978 	}
979 
980 	if (combo & IVTV_IRQ_ENC_DMA_COMPLETE) {
981 		ivtv_irq_enc_dma_complete(itv);
982 	}
983 
984 	if (combo & IVTV_IRQ_ENC_PIO_COMPLETE) {
985 		ivtv_irq_enc_pio_complete(itv);
986 	}
987 
988 	if (combo & IVTV_IRQ_DMA_ERR) {
989 		ivtv_irq_dma_err(itv);
990 	}
991 
992 	if (combo & IVTV_IRQ_ENC_START_CAP) {
993 		ivtv_irq_enc_start_cap(itv);
994 	}
995 
996 	if (combo & IVTV_IRQ_ENC_VBI_CAP) {
997 		ivtv_irq_enc_vbi_cap(itv);
998 	}
999 
1000 	if (combo & IVTV_IRQ_DEC_VBI_RE_INSERT) {
1001 		ivtv_irq_dec_vbi_reinsert(itv);
1002 	}
1003 
1004 	if (combo & IVTV_IRQ_ENC_EOS) {
1005 		IVTV_DEBUG_IRQ("ENC EOS\n");
1006 		set_bit(IVTV_F_I_EOS, &itv->i_flags);
1007 		wake_up(&itv->eos_waitq);
1008 	}
1009 
1010 	if (combo & IVTV_IRQ_DEC_DATA_REQ) {
1011 		ivtv_irq_dec_data_req(itv);
1012 	}
1013 
1014 	/* Decoder Vertical Sync - We can't rely on 'combo', so check if vsync enabled */
1015 	if (~itv->irqmask & IVTV_IRQ_DEC_VSYNC) {
1016 		ivtv_irq_vsync(itv);
1017 	}
1018 
1019 	if (combo & IVTV_IRQ_ENC_VIM_RST) {
1020 		IVTV_DEBUG_IRQ("VIM RST\n");
1021 		/*ivtv_vapi(itv, CX2341X_ENC_REFRESH_INPUT, 0); */
1022 	}
1023 
1024 	if (combo & IVTV_IRQ_DEC_AUD_MODE_CHG) {
1025 		IVTV_DEBUG_INFO("Stereo mode changed\n");
1026 	}
1027 
1028 	if ((combo & IVTV_IRQ_DMA) && !test_bit(IVTV_F_I_DMA, &itv->i_flags)) {
1029 		itv->irq_rr_idx++;
1030 		for (i = 0; i < IVTV_MAX_STREAMS; i++) {
1031 			int idx = (i + itv->irq_rr_idx) % IVTV_MAX_STREAMS;
1032 			struct ivtv_stream *s = &itv->streams[idx];
1033 
1034 			if (!test_and_clear_bit(IVTV_F_S_DMA_PENDING, &s->s_flags))
1035 				continue;
1036 			if (s->type >= IVTV_DEC_STREAM_TYPE_MPG)
1037 				ivtv_dma_dec_start(s);
1038 			else
1039 				ivtv_dma_enc_start(s);
1040 			break;
1041 		}
1042 
1043 		if (i == IVTV_MAX_STREAMS &&
1044 		    test_bit(IVTV_F_I_UDMA_PENDING, &itv->i_flags))
1045 			ivtv_udma_start(itv);
1046 	}
1047 
1048 	if ((combo & IVTV_IRQ_DMA) && !test_bit(IVTV_F_I_PIO, &itv->i_flags)) {
1049 		itv->irq_rr_idx++;
1050 		for (i = 0; i < IVTV_MAX_STREAMS; i++) {
1051 			int idx = (i + itv->irq_rr_idx) % IVTV_MAX_STREAMS;
1052 			struct ivtv_stream *s = &itv->streams[idx];
1053 
1054 			if (!test_and_clear_bit(IVTV_F_S_PIO_PENDING, &s->s_flags))
1055 				continue;
1056 			if (s->type == IVTV_DEC_STREAM_TYPE_VBI || s->type < IVTV_DEC_STREAM_TYPE_MPG)
1057 				ivtv_dma_enc_start(s);
1058 			break;
1059 		}
1060 	}
1061 
1062 	if (test_and_clear_bit(IVTV_F_I_HAVE_WORK, &itv->i_flags)) {
1063 		queue_kthread_work(&itv->irq_worker, &itv->irq_work);
1064 	}
1065 
1066 	spin_unlock(&itv->dma_reg_lock);
1067 
1068 	/* If we've just handled a 'forced' vsync, it's safest to say it
1069 	 * wasn't ours. Another device may have triggered it at just
1070 	 * the right time.
1071 	 */
1072 	return vsync_force ? IRQ_NONE : IRQ_HANDLED;
1073 }
1074 
1075 void ivtv_unfinished_dma(unsigned long arg)
1076 {
1077 	struct ivtv *itv = (struct ivtv *)arg;
1078 
1079 	if (!test_bit(IVTV_F_I_DMA, &itv->i_flags))
1080 		return;
1081 	IVTV_ERR("DMA TIMEOUT %08x %d\n", read_reg(IVTV_REG_DMASTATUS), itv->cur_dma_stream);
1082 
1083 	write_reg(read_reg(IVTV_REG_DMASTATUS) & 3, IVTV_REG_DMASTATUS);
1084 	clear_bit(IVTV_F_I_UDMA, &itv->i_flags);
1085 	clear_bit(IVTV_F_I_DMA, &itv->i_flags);
1086 	itv->cur_dma_stream = -1;
1087 	wake_up(&itv->dma_waitq);
1088 }
1089