xref: /openbmc/linux/drivers/media/pci/ivtv/ivtv-irq.c (revision 7f6964c5)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* interrupt handling
3     Copyright (C) 2003-2004  Kevin Thayer <nufan_wfk at yahoo.com>
4     Copyright (C) 2004  Chris Kennedy <c@groovy.org>
5     Copyright (C) 2005-2007  Hans Verkuil <hverkuil@xs4all.nl>
6 
7  */
8 
9 #include "ivtv-driver.h"
10 #include "ivtv-queue.h"
11 #include "ivtv-udma.h"
12 #include "ivtv-irq.h"
13 #include "ivtv-mailbox.h"
14 #include "ivtv-vbi.h"
15 #include "ivtv-yuv.h"
16 #include <media/v4l2-event.h>
17 
18 #define DMA_MAGIC_COOKIE 0x000001fe
19 
20 static void ivtv_dma_dec_start(struct ivtv_stream *s);
21 
22 static const int ivtv_stream_map[] = {
23 	IVTV_ENC_STREAM_TYPE_MPG,
24 	IVTV_ENC_STREAM_TYPE_YUV,
25 	IVTV_ENC_STREAM_TYPE_PCM,
26 	IVTV_ENC_STREAM_TYPE_VBI,
27 };
28 
29 static void ivtv_pcm_work_handler(struct ivtv *itv)
30 {
31 	struct ivtv_stream *s = &itv->streams[IVTV_ENC_STREAM_TYPE_PCM];
32 	struct ivtv_buffer *buf;
33 
34 	/* Pass the PCM data to ivtv-alsa */
35 
36 	while (1) {
37 		/*
38 		 * Users should not be using both the ALSA and V4L2 PCM audio
39 		 * capture interfaces at the same time.  If the user is doing
40 		 * this, there maybe a buffer in q_io to grab, use, and put
41 		 * back in rotation.
42 		 */
43 		buf = ivtv_dequeue(s, &s->q_io);
44 		if (buf == NULL)
45 			buf = ivtv_dequeue(s, &s->q_full);
46 		if (buf == NULL)
47 			break;
48 
49 		if (buf->readpos < buf->bytesused)
50 			itv->pcm_announce_callback(itv->alsa,
51 				(u8 *)(buf->buf + buf->readpos),
52 				(size_t)(buf->bytesused - buf->readpos));
53 
54 		ivtv_enqueue(s, buf, &s->q_free);
55 	}
56 }
57 
58 static void ivtv_pio_work_handler(struct ivtv *itv)
59 {
60 	struct ivtv_stream *s = &itv->streams[itv->cur_pio_stream];
61 	struct ivtv_buffer *buf;
62 	int i = 0;
63 
64 	IVTV_DEBUG_HI_DMA("ivtv_pio_work_handler\n");
65 	if (itv->cur_pio_stream < 0 || itv->cur_pio_stream >= IVTV_MAX_STREAMS ||
66 			s->vdev.v4l2_dev == NULL || !ivtv_use_pio(s)) {
67 		itv->cur_pio_stream = -1;
68 		/* trigger PIO complete user interrupt */
69 		write_reg(IVTV_IRQ_ENC_PIO_COMPLETE, 0x44);
70 		return;
71 	}
72 	IVTV_DEBUG_HI_DMA("Process PIO %s\n", s->name);
73 	list_for_each_entry(buf, &s->q_dma.list, list) {
74 		u32 size = s->sg_processing[i].size & 0x3ffff;
75 
76 		/* Copy the data from the card to the buffer */
77 		if (s->type == IVTV_DEC_STREAM_TYPE_VBI) {
78 			memcpy_fromio(buf->buf, itv->dec_mem + s->sg_processing[i].src - IVTV_DECODER_OFFSET, size);
79 		}
80 		else {
81 			memcpy_fromio(buf->buf, itv->enc_mem + s->sg_processing[i].src, size);
82 		}
83 		i++;
84 		if (i == s->sg_processing_size)
85 			break;
86 	}
87 	write_reg(IVTV_IRQ_ENC_PIO_COMPLETE, 0x44);
88 }
89 
90 void ivtv_irq_work_handler(struct kthread_work *work)
91 {
92 	struct ivtv *itv = container_of(work, struct ivtv, irq_work);
93 
94 	if (test_and_clear_bit(IVTV_F_I_WORK_HANDLER_PIO, &itv->i_flags))
95 		ivtv_pio_work_handler(itv);
96 
97 	if (test_and_clear_bit(IVTV_F_I_WORK_HANDLER_VBI, &itv->i_flags))
98 		ivtv_vbi_work_handler(itv);
99 
100 	if (test_and_clear_bit(IVTV_F_I_WORK_HANDLER_YUV, &itv->i_flags))
101 		ivtv_yuv_work_handler(itv);
102 
103 	if (test_and_clear_bit(IVTV_F_I_WORK_HANDLER_PCM, &itv->i_flags))
104 		ivtv_pcm_work_handler(itv);
105 }
106 
107 /* Determine the required DMA size, setup enough buffers in the predma queue and
108    actually copy the data from the card to the buffers in case a PIO transfer is
109    required for this stream.
110  */
111 static int stream_enc_dma_append(struct ivtv_stream *s, u32 data[CX2341X_MBOX_MAX_DATA])
112 {
113 	struct ivtv *itv = s->itv;
114 	struct ivtv_buffer *buf;
115 	u32 bytes_needed = 0;
116 	u32 offset, size;
117 	u32 UVoffset = 0, UVsize = 0;
118 	int skip_bufs = s->q_predma.buffers;
119 	int idx = s->sg_pending_size;
120 	int rc;
121 
122 	/* sanity checks */
123 	if (s->vdev.v4l2_dev == NULL) {
124 		IVTV_DEBUG_WARN("Stream %s not started\n", s->name);
125 		return -1;
126 	}
127 	if (!test_bit(IVTV_F_S_CLAIMED, &s->s_flags)) {
128 		IVTV_DEBUG_WARN("Stream %s not open\n", s->name);
129 		return -1;
130 	}
131 
132 	/* determine offset, size and PTS for the various streams */
133 	switch (s->type) {
134 		case IVTV_ENC_STREAM_TYPE_MPG:
135 			offset = data[1];
136 			size = data[2];
137 			s->pending_pts = 0;
138 			break;
139 
140 		case IVTV_ENC_STREAM_TYPE_YUV:
141 			offset = data[1];
142 			size = data[2];
143 			UVoffset = data[3];
144 			UVsize = data[4];
145 			s->pending_pts = ((u64) data[5] << 32) | data[6];
146 			break;
147 
148 		case IVTV_ENC_STREAM_TYPE_PCM:
149 			offset = data[1] + 12;
150 			size = data[2] - 12;
151 			s->pending_pts = read_dec(offset - 8) |
152 				((u64)(read_dec(offset - 12)) << 32);
153 			if (itv->has_cx23415)
154 				offset += IVTV_DECODER_OFFSET;
155 			break;
156 
157 		case IVTV_ENC_STREAM_TYPE_VBI:
158 			size = itv->vbi.enc_size * itv->vbi.fpi;
159 			offset = read_enc(itv->vbi.enc_start - 4) + 12;
160 			if (offset == 12) {
161 				IVTV_DEBUG_INFO("VBI offset == 0\n");
162 				return -1;
163 			}
164 			s->pending_pts = read_enc(offset - 4) | ((u64)read_enc(offset - 8) << 32);
165 			break;
166 
167 		case IVTV_DEC_STREAM_TYPE_VBI:
168 			size = read_dec(itv->vbi.dec_start + 4) + 8;
169 			offset = read_dec(itv->vbi.dec_start) + itv->vbi.dec_start;
170 			s->pending_pts = 0;
171 			offset += IVTV_DECODER_OFFSET;
172 			break;
173 		default:
174 			/* shouldn't happen */
175 			return -1;
176 	}
177 
178 	/* if this is the start of the DMA then fill in the magic cookie */
179 	if (s->sg_pending_size == 0 && ivtv_use_dma(s)) {
180 		if (itv->has_cx23415 && (s->type == IVTV_ENC_STREAM_TYPE_PCM ||
181 		    s->type == IVTV_DEC_STREAM_TYPE_VBI)) {
182 			s->pending_backup = read_dec(offset - IVTV_DECODER_OFFSET);
183 			write_dec_sync(DMA_MAGIC_COOKIE, offset - IVTV_DECODER_OFFSET);
184 		}
185 		else {
186 			s->pending_backup = read_enc(offset);
187 			write_enc_sync(DMA_MAGIC_COOKIE, offset);
188 		}
189 		s->pending_offset = offset;
190 	}
191 
192 	bytes_needed = size;
193 	if (s->type == IVTV_ENC_STREAM_TYPE_YUV) {
194 		/* The size for the Y samples needs to be rounded upwards to a
195 		   multiple of the buf_size. The UV samples then start in the
196 		   next buffer. */
197 		bytes_needed = s->buf_size * ((bytes_needed + s->buf_size - 1) / s->buf_size);
198 		bytes_needed += UVsize;
199 	}
200 
201 	IVTV_DEBUG_HI_DMA("%s %s: 0x%08x bytes at 0x%08x\n",
202 		ivtv_use_pio(s) ? "PIO" : "DMA", s->name, bytes_needed, offset);
203 
204 	rc = ivtv_queue_move(s, &s->q_free, &s->q_full, &s->q_predma, bytes_needed);
205 	if (rc < 0) { /* Insufficient buffers */
206 		IVTV_DEBUG_WARN("Cannot obtain %d bytes for %s data transfer\n",
207 				bytes_needed, s->name);
208 		return -1;
209 	}
210 	if (rc && !s->buffers_stolen && test_bit(IVTV_F_S_APPL_IO, &s->s_flags)) {
211 		IVTV_WARN("All %s stream buffers are full. Dropping data.\n", s->name);
212 		IVTV_WARN("Cause: the application is not reading fast enough.\n");
213 	}
214 	s->buffers_stolen = rc;
215 
216 	/* got the buffers, now fill in sg_pending */
217 	buf = list_entry(s->q_predma.list.next, struct ivtv_buffer, list);
218 	memset(buf->buf, 0, 128);
219 	list_for_each_entry(buf, &s->q_predma.list, list) {
220 		if (skip_bufs-- > 0)
221 			continue;
222 		s->sg_pending[idx].dst = buf->dma_handle;
223 		s->sg_pending[idx].src = offset;
224 		s->sg_pending[idx].size = s->buf_size;
225 		buf->bytesused = min(size, s->buf_size);
226 		buf->dma_xfer_cnt = s->dma_xfer_cnt;
227 
228 		s->q_predma.bytesused += buf->bytesused;
229 		size -= buf->bytesused;
230 		offset += s->buf_size;
231 
232 		/* Sync SG buffers */
233 		ivtv_buf_sync_for_device(s, buf);
234 
235 		if (size == 0) {	/* YUV */
236 			/* process the UV section */
237 			offset = UVoffset;
238 			size = UVsize;
239 		}
240 		idx++;
241 	}
242 	s->sg_pending_size = idx;
243 	return 0;
244 }
245 
246 static void dma_post(struct ivtv_stream *s)
247 {
248 	struct ivtv *itv = s->itv;
249 	struct ivtv_buffer *buf = NULL;
250 	struct list_head *p;
251 	u32 offset;
252 	__le32 *u32buf;
253 	int x = 0;
254 
255 	IVTV_DEBUG_HI_DMA("%s %s completed (%x)\n", ivtv_use_pio(s) ? "PIO" : "DMA",
256 			s->name, s->dma_offset);
257 	list_for_each(p, &s->q_dma.list) {
258 		buf = list_entry(p, struct ivtv_buffer, list);
259 		u32buf = (__le32 *)buf->buf;
260 
261 		/* Sync Buffer */
262 		ivtv_buf_sync_for_cpu(s, buf);
263 
264 		if (x == 0 && ivtv_use_dma(s)) {
265 			offset = s->dma_last_offset;
266 			if (le32_to_cpu(u32buf[offset / 4]) != DMA_MAGIC_COOKIE)
267 			{
268 				for (offset = 0; offset < 64; offset++)
269 					if (le32_to_cpu(u32buf[offset]) == DMA_MAGIC_COOKIE)
270 						break;
271 				offset *= 4;
272 				if (offset == 256) {
273 					IVTV_DEBUG_WARN("%s: Couldn't find start of buffer within the first 256 bytes\n", s->name);
274 					offset = s->dma_last_offset;
275 				}
276 				if (s->dma_last_offset != offset)
277 					IVTV_DEBUG_WARN("%s: offset %d -> %d\n", s->name, s->dma_last_offset, offset);
278 				s->dma_last_offset = offset;
279 			}
280 			if (itv->has_cx23415 && (s->type == IVTV_ENC_STREAM_TYPE_PCM ||
281 						s->type == IVTV_DEC_STREAM_TYPE_VBI)) {
282 				write_dec_sync(0, s->dma_offset - IVTV_DECODER_OFFSET);
283 			}
284 			else {
285 				write_enc_sync(0, s->dma_offset);
286 			}
287 			if (offset) {
288 				buf->bytesused -= offset;
289 				memcpy(buf->buf, buf->buf + offset, buf->bytesused + offset);
290 			}
291 			*u32buf = cpu_to_le32(s->dma_backup);
292 		}
293 		x++;
294 		/* flag byteswap ABCD -> DCBA for MPG & VBI data outside irq */
295 		if (s->type == IVTV_ENC_STREAM_TYPE_MPG ||
296 		    s->type == IVTV_ENC_STREAM_TYPE_VBI)
297 			buf->b_flags |= IVTV_F_B_NEED_BUF_SWAP;
298 	}
299 	if (buf)
300 		buf->bytesused += s->dma_last_offset;
301 	if (buf && s->type == IVTV_DEC_STREAM_TYPE_VBI) {
302 		list_for_each_entry(buf, &s->q_dma.list, list) {
303 			/* Parse and Groom VBI Data */
304 			s->q_dma.bytesused -= buf->bytesused;
305 			ivtv_process_vbi_data(itv, buf, 0, s->type);
306 			s->q_dma.bytesused += buf->bytesused;
307 		}
308 		if (s->fh == NULL) {
309 			ivtv_queue_move(s, &s->q_dma, NULL, &s->q_free, 0);
310 			return;
311 		}
312 	}
313 
314 	ivtv_queue_move(s, &s->q_dma, NULL, &s->q_full, s->q_dma.bytesused);
315 
316 	if (s->type == IVTV_ENC_STREAM_TYPE_PCM &&
317 	    itv->pcm_announce_callback != NULL) {
318 		/*
319 		 * Set up the work handler to pass the data to ivtv-alsa.
320 		 *
321 		 * We just use q_full and let the work handler race with users
322 		 * making ivtv-fileops.c calls on the PCM device node.
323 		 *
324 		 * Users should not be using both the ALSA and V4L2 PCM audio
325 		 * capture interfaces at the same time.  If the user does this,
326 		 * fragments of data will just go out each interface as they
327 		 * race for PCM data.
328 		 */
329 		set_bit(IVTV_F_I_WORK_HANDLER_PCM, &itv->i_flags);
330 		set_bit(IVTV_F_I_HAVE_WORK, &itv->i_flags);
331 	}
332 
333 	if (s->fh)
334 		wake_up(&s->waitq);
335 }
336 
337 void ivtv_dma_stream_dec_prepare(struct ivtv_stream *s, u32 offset, int lock)
338 {
339 	struct ivtv *itv = s->itv;
340 	struct yuv_playback_info *yi = &itv->yuv_info;
341 	u8 frame = yi->draw_frame;
342 	struct yuv_frame_info *f = &yi->new_frame_info[frame];
343 	struct ivtv_buffer *buf;
344 	u32 y_size = 720 * ((f->src_h + 31) & ~31);
345 	u32 uv_offset = offset + IVTV_YUV_BUFFER_UV_OFFSET;
346 	int y_done = 0;
347 	int bytes_written = 0;
348 	int idx = 0;
349 
350 	IVTV_DEBUG_HI_DMA("DEC PREPARE DMA %s: %08x %08x\n", s->name, s->q_predma.bytesused, offset);
351 
352 	/* Insert buffer block for YUV if needed */
353 	if (s->type == IVTV_DEC_STREAM_TYPE_YUV && f->offset_y) {
354 		if (yi->blanking_dmaptr) {
355 			s->sg_pending[idx].src = yi->blanking_dmaptr;
356 			s->sg_pending[idx].dst = offset;
357 			s->sg_pending[idx].size = 720 * 16;
358 		}
359 		offset += 720 * 16;
360 		idx++;
361 	}
362 
363 	list_for_each_entry(buf, &s->q_predma.list, list) {
364 		/* YUV UV Offset from Y Buffer */
365 		if (s->type == IVTV_DEC_STREAM_TYPE_YUV && !y_done &&
366 				(bytes_written + buf->bytesused) >= y_size) {
367 			s->sg_pending[idx].src = buf->dma_handle;
368 			s->sg_pending[idx].dst = offset;
369 			s->sg_pending[idx].size = y_size - bytes_written;
370 			offset = uv_offset;
371 			if (s->sg_pending[idx].size != buf->bytesused) {
372 				idx++;
373 				s->sg_pending[idx].src =
374 				  buf->dma_handle + s->sg_pending[idx - 1].size;
375 				s->sg_pending[idx].dst = offset;
376 				s->sg_pending[idx].size =
377 				   buf->bytesused - s->sg_pending[idx - 1].size;
378 				offset += s->sg_pending[idx].size;
379 			}
380 			y_done = 1;
381 		} else {
382 			s->sg_pending[idx].src = buf->dma_handle;
383 			s->sg_pending[idx].dst = offset;
384 			s->sg_pending[idx].size = buf->bytesused;
385 			offset += buf->bytesused;
386 		}
387 		bytes_written += buf->bytesused;
388 
389 		/* Sync SG buffers */
390 		ivtv_buf_sync_for_device(s, buf);
391 		idx++;
392 	}
393 	s->sg_pending_size = idx;
394 
395 	/* Sync Hardware SG List of buffers */
396 	ivtv_stream_sync_for_device(s);
397 	if (lock) {
398 		unsigned long flags = 0;
399 
400 		spin_lock_irqsave(&itv->dma_reg_lock, flags);
401 		if (!test_bit(IVTV_F_I_DMA, &itv->i_flags))
402 			ivtv_dma_dec_start(s);
403 		else
404 			set_bit(IVTV_F_S_DMA_PENDING, &s->s_flags);
405 		spin_unlock_irqrestore(&itv->dma_reg_lock, flags);
406 	} else {
407 		if (!test_bit(IVTV_F_I_DMA, &itv->i_flags))
408 			ivtv_dma_dec_start(s);
409 		else
410 			set_bit(IVTV_F_S_DMA_PENDING, &s->s_flags);
411 	}
412 }
413 
414 static void ivtv_dma_enc_start_xfer(struct ivtv_stream *s)
415 {
416 	struct ivtv *itv = s->itv;
417 
418 	s->sg_dma->src = cpu_to_le32(s->sg_processing[s->sg_processed].src);
419 	s->sg_dma->dst = cpu_to_le32(s->sg_processing[s->sg_processed].dst);
420 	s->sg_dma->size = cpu_to_le32(s->sg_processing[s->sg_processed].size | 0x80000000);
421 	s->sg_processed++;
422 	/* Sync Hardware SG List of buffers */
423 	ivtv_stream_sync_for_device(s);
424 	write_reg(s->sg_handle, IVTV_REG_ENCDMAADDR);
425 	write_reg_sync(read_reg(IVTV_REG_DMAXFER) | 0x02, IVTV_REG_DMAXFER);
426 	itv->dma_timer.expires = jiffies + msecs_to_jiffies(300);
427 	add_timer(&itv->dma_timer);
428 }
429 
430 static void ivtv_dma_dec_start_xfer(struct ivtv_stream *s)
431 {
432 	struct ivtv *itv = s->itv;
433 
434 	s->sg_dma->src = cpu_to_le32(s->sg_processing[s->sg_processed].src);
435 	s->sg_dma->dst = cpu_to_le32(s->sg_processing[s->sg_processed].dst);
436 	s->sg_dma->size = cpu_to_le32(s->sg_processing[s->sg_processed].size | 0x80000000);
437 	s->sg_processed++;
438 	/* Sync Hardware SG List of buffers */
439 	ivtv_stream_sync_for_device(s);
440 	write_reg(s->sg_handle, IVTV_REG_DECDMAADDR);
441 	write_reg_sync(read_reg(IVTV_REG_DMAXFER) | 0x01, IVTV_REG_DMAXFER);
442 	itv->dma_timer.expires = jiffies + msecs_to_jiffies(300);
443 	add_timer(&itv->dma_timer);
444 }
445 
446 /* start the encoder DMA */
447 static void ivtv_dma_enc_start(struct ivtv_stream *s)
448 {
449 	struct ivtv *itv = s->itv;
450 	struct ivtv_stream *s_vbi = &itv->streams[IVTV_ENC_STREAM_TYPE_VBI];
451 	int i;
452 
453 	IVTV_DEBUG_HI_DMA("start %s for %s\n", ivtv_use_dma(s) ? "DMA" : "PIO", s->name);
454 
455 	if (s->q_predma.bytesused)
456 		ivtv_queue_move(s, &s->q_predma, NULL, &s->q_dma, s->q_predma.bytesused);
457 
458 	if (ivtv_use_dma(s))
459 		s->sg_pending[s->sg_pending_size - 1].size += 256;
460 
461 	/* If this is an MPEG stream, and VBI data is also pending, then append the
462 	   VBI DMA to the MPEG DMA and transfer both sets of data at once.
463 
464 	   VBI DMA is a second class citizen compared to MPEG and mixing them together
465 	   will confuse the firmware (the end of a VBI DMA is seen as the end of a
466 	   MPEG DMA, thus effectively dropping an MPEG frame). So instead we make
467 	   sure we only use the MPEG DMA to transfer the VBI DMA if both are in
468 	   use. This way no conflicts occur. */
469 	clear_bit(IVTV_F_S_DMA_HAS_VBI, &s->s_flags);
470 	if (s->type == IVTV_ENC_STREAM_TYPE_MPG && s_vbi->sg_pending_size &&
471 			s->sg_pending_size + s_vbi->sg_pending_size <= s->buffers) {
472 		ivtv_queue_move(s_vbi, &s_vbi->q_predma, NULL, &s_vbi->q_dma, s_vbi->q_predma.bytesused);
473 		if (ivtv_use_dma(s_vbi))
474 			s_vbi->sg_pending[s_vbi->sg_pending_size - 1].size += 256;
475 		for (i = 0; i < s_vbi->sg_pending_size; i++) {
476 			s->sg_pending[s->sg_pending_size++] = s_vbi->sg_pending[i];
477 		}
478 		s_vbi->dma_offset = s_vbi->pending_offset;
479 		s_vbi->sg_pending_size = 0;
480 		s_vbi->dma_xfer_cnt++;
481 		set_bit(IVTV_F_S_DMA_HAS_VBI, &s->s_flags);
482 		IVTV_DEBUG_HI_DMA("include DMA for %s\n", s_vbi->name);
483 	}
484 
485 	s->dma_xfer_cnt++;
486 	memcpy(s->sg_processing, s->sg_pending, sizeof(struct ivtv_sg_host_element) * s->sg_pending_size);
487 	s->sg_processing_size = s->sg_pending_size;
488 	s->sg_pending_size = 0;
489 	s->sg_processed = 0;
490 	s->dma_offset = s->pending_offset;
491 	s->dma_backup = s->pending_backup;
492 	s->dma_pts = s->pending_pts;
493 
494 	if (ivtv_use_pio(s)) {
495 		set_bit(IVTV_F_I_WORK_HANDLER_PIO, &itv->i_flags);
496 		set_bit(IVTV_F_I_HAVE_WORK, &itv->i_flags);
497 		set_bit(IVTV_F_I_PIO, &itv->i_flags);
498 		itv->cur_pio_stream = s->type;
499 	}
500 	else {
501 		itv->dma_retries = 0;
502 		ivtv_dma_enc_start_xfer(s);
503 		set_bit(IVTV_F_I_DMA, &itv->i_flags);
504 		itv->cur_dma_stream = s->type;
505 	}
506 }
507 
508 static void ivtv_dma_dec_start(struct ivtv_stream *s)
509 {
510 	struct ivtv *itv = s->itv;
511 
512 	if (s->q_predma.bytesused)
513 		ivtv_queue_move(s, &s->q_predma, NULL, &s->q_dma, s->q_predma.bytesused);
514 	s->dma_xfer_cnt++;
515 	memcpy(s->sg_processing, s->sg_pending, sizeof(struct ivtv_sg_host_element) * s->sg_pending_size);
516 	s->sg_processing_size = s->sg_pending_size;
517 	s->sg_pending_size = 0;
518 	s->sg_processed = 0;
519 
520 	IVTV_DEBUG_HI_DMA("start DMA for %s\n", s->name);
521 	itv->dma_retries = 0;
522 	ivtv_dma_dec_start_xfer(s);
523 	set_bit(IVTV_F_I_DMA, &itv->i_flags);
524 	itv->cur_dma_stream = s->type;
525 }
526 
527 static void ivtv_irq_dma_read(struct ivtv *itv)
528 {
529 	struct ivtv_stream *s = NULL;
530 	struct ivtv_buffer *buf;
531 	int hw_stream_type = 0;
532 
533 	IVTV_DEBUG_HI_IRQ("DEC DMA READ\n");
534 
535 	del_timer(&itv->dma_timer);
536 
537 	if (!test_bit(IVTV_F_I_UDMA, &itv->i_flags) && itv->cur_dma_stream < 0)
538 		return;
539 
540 	if (!test_bit(IVTV_F_I_UDMA, &itv->i_flags)) {
541 		s = &itv->streams[itv->cur_dma_stream];
542 		ivtv_stream_sync_for_cpu(s);
543 
544 		if (read_reg(IVTV_REG_DMASTATUS) & 0x14) {
545 			IVTV_DEBUG_WARN("DEC DMA ERROR %x (xfer %d of %d, retry %d)\n",
546 					read_reg(IVTV_REG_DMASTATUS),
547 					s->sg_processed, s->sg_processing_size, itv->dma_retries);
548 			write_reg(read_reg(IVTV_REG_DMASTATUS) & 3, IVTV_REG_DMASTATUS);
549 			if (itv->dma_retries == 3) {
550 				/* Too many retries, give up on this frame */
551 				itv->dma_retries = 0;
552 				s->sg_processed = s->sg_processing_size;
553 			}
554 			else {
555 				/* Retry, starting with the first xfer segment.
556 				   Just retrying the current segment is not sufficient. */
557 				s->sg_processed = 0;
558 				itv->dma_retries++;
559 			}
560 		}
561 		if (s->sg_processed < s->sg_processing_size) {
562 			/* DMA next buffer */
563 			ivtv_dma_dec_start_xfer(s);
564 			return;
565 		}
566 		if (s->type == IVTV_DEC_STREAM_TYPE_YUV)
567 			hw_stream_type = 2;
568 		IVTV_DEBUG_HI_DMA("DEC DATA READ %s: %d\n", s->name, s->q_dma.bytesused);
569 
570 		/* For some reason must kick the firmware, like PIO mode,
571 		   I think this tells the firmware we are done and the size
572 		   of the xfer so it can calculate what we need next.
573 		   I think we can do this part ourselves but would have to
574 		   fully calculate xfer info ourselves and not use interrupts
575 		 */
576 		ivtv_vapi(itv, CX2341X_DEC_SCHED_DMA_FROM_HOST, 3, 0, s->q_dma.bytesused,
577 				hw_stream_type);
578 
579 		/* Free last DMA call */
580 		while ((buf = ivtv_dequeue(s, &s->q_dma)) != NULL) {
581 			ivtv_buf_sync_for_cpu(s, buf);
582 			ivtv_enqueue(s, buf, &s->q_free);
583 		}
584 		wake_up(&s->waitq);
585 	}
586 	clear_bit(IVTV_F_I_UDMA, &itv->i_flags);
587 	clear_bit(IVTV_F_I_DMA, &itv->i_flags);
588 	itv->cur_dma_stream = -1;
589 	wake_up(&itv->dma_waitq);
590 }
591 
592 static void ivtv_irq_enc_dma_complete(struct ivtv *itv)
593 {
594 	u32 data[CX2341X_MBOX_MAX_DATA];
595 	struct ivtv_stream *s;
596 
597 	ivtv_api_get_data(&itv->enc_mbox, IVTV_MBOX_DMA_END, 2, data);
598 	IVTV_DEBUG_HI_IRQ("ENC DMA COMPLETE %x %d (%d)\n", data[0], data[1], itv->cur_dma_stream);
599 
600 	del_timer(&itv->dma_timer);
601 
602 	if (itv->cur_dma_stream < 0)
603 		return;
604 
605 	s = &itv->streams[itv->cur_dma_stream];
606 	ivtv_stream_sync_for_cpu(s);
607 
608 	if (data[0] & 0x18) {
609 		IVTV_DEBUG_WARN("ENC DMA ERROR %x (offset %08x, xfer %d of %d, retry %d)\n", data[0],
610 			s->dma_offset, s->sg_processed, s->sg_processing_size, itv->dma_retries);
611 		write_reg(read_reg(IVTV_REG_DMASTATUS) & 3, IVTV_REG_DMASTATUS);
612 		if (itv->dma_retries == 3) {
613 			/* Too many retries, give up on this frame */
614 			itv->dma_retries = 0;
615 			s->sg_processed = s->sg_processing_size;
616 		}
617 		else {
618 			/* Retry, starting with the first xfer segment.
619 			   Just retrying the current segment is not sufficient. */
620 			s->sg_processed = 0;
621 			itv->dma_retries++;
622 		}
623 	}
624 	if (s->sg_processed < s->sg_processing_size) {
625 		/* DMA next buffer */
626 		ivtv_dma_enc_start_xfer(s);
627 		return;
628 	}
629 	clear_bit(IVTV_F_I_DMA, &itv->i_flags);
630 	itv->cur_dma_stream = -1;
631 	dma_post(s);
632 	if (test_and_clear_bit(IVTV_F_S_DMA_HAS_VBI, &s->s_flags)) {
633 		s = &itv->streams[IVTV_ENC_STREAM_TYPE_VBI];
634 		dma_post(s);
635 	}
636 	s->sg_processing_size = 0;
637 	s->sg_processed = 0;
638 	wake_up(&itv->dma_waitq);
639 }
640 
641 static void ivtv_irq_enc_pio_complete(struct ivtv *itv)
642 {
643 	struct ivtv_stream *s;
644 
645 	if (itv->cur_pio_stream < 0 || itv->cur_pio_stream >= IVTV_MAX_STREAMS) {
646 		itv->cur_pio_stream = -1;
647 		return;
648 	}
649 	s = &itv->streams[itv->cur_pio_stream];
650 	IVTV_DEBUG_HI_IRQ("ENC PIO COMPLETE %s\n", s->name);
651 	clear_bit(IVTV_F_I_PIO, &itv->i_flags);
652 	itv->cur_pio_stream = -1;
653 	dma_post(s);
654 	if (s->type == IVTV_ENC_STREAM_TYPE_MPG)
655 		ivtv_vapi(itv, CX2341X_ENC_SCHED_DMA_TO_HOST, 3, 0, 0, 0);
656 	else if (s->type == IVTV_ENC_STREAM_TYPE_YUV)
657 		ivtv_vapi(itv, CX2341X_ENC_SCHED_DMA_TO_HOST, 3, 0, 0, 1);
658 	else if (s->type == IVTV_ENC_STREAM_TYPE_PCM)
659 		ivtv_vapi(itv, CX2341X_ENC_SCHED_DMA_TO_HOST, 3, 0, 0, 2);
660 	clear_bit(IVTV_F_I_PIO, &itv->i_flags);
661 	if (test_and_clear_bit(IVTV_F_S_DMA_HAS_VBI, &s->s_flags)) {
662 		s = &itv->streams[IVTV_ENC_STREAM_TYPE_VBI];
663 		dma_post(s);
664 	}
665 	wake_up(&itv->dma_waitq);
666 }
667 
668 static void ivtv_irq_dma_err(struct ivtv *itv)
669 {
670 	u32 data[CX2341X_MBOX_MAX_DATA];
671 	u32 status;
672 
673 	del_timer(&itv->dma_timer);
674 
675 	ivtv_api_get_data(&itv->enc_mbox, IVTV_MBOX_DMA_END, 2, data);
676 	status = read_reg(IVTV_REG_DMASTATUS);
677 	IVTV_DEBUG_WARN("DMA ERROR %08x %08x %08x %d\n", data[0], data[1],
678 				status, itv->cur_dma_stream);
679 	/*
680 	 * We do *not* write back to the IVTV_REG_DMASTATUS register to
681 	 * clear the error status, if either the encoder write (0x02) or
682 	 * decoder read (0x01) bus master DMA operation do not indicate
683 	 * completed.  We can race with the DMA engine, which may have
684 	 * transitioned to completed status *after* we read the register.
685 	 * Setting a IVTV_REG_DMASTATUS flag back to "busy" status, after the
686 	 * DMA engine has completed, will cause the DMA engine to stop working.
687 	 */
688 	status &= 0x3;
689 	if (status == 0x3)
690 		write_reg(status, IVTV_REG_DMASTATUS);
691 
692 	if (!test_bit(IVTV_F_I_UDMA, &itv->i_flags) &&
693 	    itv->cur_dma_stream >= 0 && itv->cur_dma_stream < IVTV_MAX_STREAMS) {
694 		struct ivtv_stream *s = &itv->streams[itv->cur_dma_stream];
695 
696 		if (s->type >= IVTV_DEC_STREAM_TYPE_MPG) {
697 			/* retry */
698 			/*
699 			 * FIXME - handle cases of DMA error similar to
700 			 * encoder below, except conditioned on status & 0x1
701 			 */
702 			ivtv_dma_dec_start(s);
703 			return;
704 		} else {
705 			if ((status & 0x2) == 0) {
706 				/*
707 				 * CX2341x Bus Master DMA write is ongoing.
708 				 * Reset the timer and let it complete.
709 				 */
710 				itv->dma_timer.expires =
711 						jiffies + msecs_to_jiffies(600);
712 				add_timer(&itv->dma_timer);
713 				return;
714 			}
715 
716 			if (itv->dma_retries < 3) {
717 				/*
718 				 * CX2341x Bus Master DMA write has ended.
719 				 * Retry the write, starting with the first
720 				 * xfer segment. Just retrying the current
721 				 * segment is not sufficient.
722 				 */
723 				s->sg_processed = 0;
724 				itv->dma_retries++;
725 				ivtv_dma_enc_start_xfer(s);
726 				return;
727 			}
728 			/* Too many retries, give up on this one */
729 		}
730 
731 	}
732 	if (test_bit(IVTV_F_I_UDMA, &itv->i_flags)) {
733 		ivtv_udma_start(itv);
734 		return;
735 	}
736 	clear_bit(IVTV_F_I_UDMA, &itv->i_flags);
737 	clear_bit(IVTV_F_I_DMA, &itv->i_flags);
738 	itv->cur_dma_stream = -1;
739 	wake_up(&itv->dma_waitq);
740 }
741 
742 static void ivtv_irq_enc_start_cap(struct ivtv *itv)
743 {
744 	u32 data[CX2341X_MBOX_MAX_DATA];
745 	struct ivtv_stream *s;
746 
747 	/* Get DMA destination and size arguments from card */
748 	ivtv_api_get_data(&itv->enc_mbox, IVTV_MBOX_DMA, 7, data);
749 	IVTV_DEBUG_HI_IRQ("ENC START CAP %d: %08x %08x\n", data[0], data[1], data[2]);
750 
751 	if (data[0] > 2 || data[1] == 0 || data[2] == 0) {
752 		IVTV_DEBUG_WARN("Unknown input: %08x %08x %08x\n",
753 				data[0], data[1], data[2]);
754 		return;
755 	}
756 	s = &itv->streams[ivtv_stream_map[data[0]]];
757 	if (!stream_enc_dma_append(s, data)) {
758 		set_bit(ivtv_use_pio(s) ? IVTV_F_S_PIO_PENDING : IVTV_F_S_DMA_PENDING, &s->s_flags);
759 	}
760 }
761 
762 static void ivtv_irq_enc_vbi_cap(struct ivtv *itv)
763 {
764 	u32 data[CX2341X_MBOX_MAX_DATA];
765 	struct ivtv_stream *s;
766 
767 	IVTV_DEBUG_HI_IRQ("ENC START VBI CAP\n");
768 	s = &itv->streams[IVTV_ENC_STREAM_TYPE_VBI];
769 
770 	if (!stream_enc_dma_append(s, data))
771 		set_bit(ivtv_use_pio(s) ? IVTV_F_S_PIO_PENDING : IVTV_F_S_DMA_PENDING, &s->s_flags);
772 }
773 
774 static void ivtv_irq_dec_vbi_reinsert(struct ivtv *itv)
775 {
776 	u32 data[CX2341X_MBOX_MAX_DATA];
777 	struct ivtv_stream *s = &itv->streams[IVTV_DEC_STREAM_TYPE_VBI];
778 
779 	IVTV_DEBUG_HI_IRQ("DEC VBI REINSERT\n");
780 	if (test_bit(IVTV_F_S_CLAIMED, &s->s_flags) &&
781 			!stream_enc_dma_append(s, data)) {
782 		set_bit(IVTV_F_S_PIO_PENDING, &s->s_flags);
783 	}
784 }
785 
786 static void ivtv_irq_dec_data_req(struct ivtv *itv)
787 {
788 	u32 data[CX2341X_MBOX_MAX_DATA];
789 	struct ivtv_stream *s;
790 
791 	/* YUV or MPG */
792 
793 	if (test_bit(IVTV_F_I_DEC_YUV, &itv->i_flags)) {
794 		ivtv_api_get_data(&itv->dec_mbox, IVTV_MBOX_DMA, 2, data);
795 		itv->dma_data_req_size =
796 				 1080 * ((itv->yuv_info.v4l2_src_h + 31) & ~31);
797 		itv->dma_data_req_offset = data[1];
798 		if (atomic_read(&itv->yuv_info.next_dma_frame) >= 0)
799 			ivtv_yuv_frame_complete(itv);
800 		s = &itv->streams[IVTV_DEC_STREAM_TYPE_YUV];
801 	}
802 	else {
803 		ivtv_api_get_data(&itv->dec_mbox, IVTV_MBOX_DMA, 3, data);
804 		itv->dma_data_req_size = min_t(u32, data[2], 0x10000);
805 		itv->dma_data_req_offset = data[1];
806 		s = &itv->streams[IVTV_DEC_STREAM_TYPE_MPG];
807 	}
808 	IVTV_DEBUG_HI_IRQ("DEC DATA REQ %s: %d %08x %u\n", s->name, s->q_full.bytesused,
809 		       itv->dma_data_req_offset, itv->dma_data_req_size);
810 	if (itv->dma_data_req_size == 0 || s->q_full.bytesused < itv->dma_data_req_size) {
811 		set_bit(IVTV_F_S_NEEDS_DATA, &s->s_flags);
812 	}
813 	else {
814 		if (test_bit(IVTV_F_I_DEC_YUV, &itv->i_flags))
815 			ivtv_yuv_setup_stream_frame(itv);
816 		clear_bit(IVTV_F_S_NEEDS_DATA, &s->s_flags);
817 		ivtv_queue_move(s, &s->q_full, NULL, &s->q_predma, itv->dma_data_req_size);
818 		ivtv_dma_stream_dec_prepare(s, itv->dma_data_req_offset + IVTV_DECODER_OFFSET, 0);
819 	}
820 }
821 
822 static void ivtv_irq_vsync(struct ivtv *itv)
823 {
824 	/* The vsync interrupt is unusual in that it won't clear until
825 	 * the end of the first line for the current field, at which
826 	 * point it clears itself. This can result in repeated vsync
827 	 * interrupts, or a missed vsync. Read some of the registers
828 	 * to determine the line being displayed and ensure we handle
829 	 * one vsync per frame.
830 	 */
831 	unsigned int frame = read_reg(IVTV_REG_DEC_LINE_FIELD) & 1;
832 	struct yuv_playback_info *yi = &itv->yuv_info;
833 	int last_dma_frame = atomic_read(&yi->next_dma_frame);
834 	struct yuv_frame_info *f = &yi->new_frame_info[last_dma_frame];
835 
836 	if (0) IVTV_DEBUG_IRQ("DEC VSYNC\n");
837 
838 	if (((frame ^ f->sync_field) == 0 &&
839 		((itv->last_vsync_field & 1) ^ f->sync_field)) ||
840 			(frame != (itv->last_vsync_field & 1) && !f->interlaced)) {
841 		int next_dma_frame = last_dma_frame;
842 
843 		if (!(f->interlaced && f->delay && yi->fields_lapsed < 1)) {
844 			if (next_dma_frame >= 0 && next_dma_frame != atomic_read(&yi->next_fill_frame)) {
845 				write_reg(yuv_offset[next_dma_frame] >> 4, 0x82c);
846 				write_reg((yuv_offset[next_dma_frame] + IVTV_YUV_BUFFER_UV_OFFSET) >> 4, 0x830);
847 				write_reg(yuv_offset[next_dma_frame] >> 4, 0x834);
848 				write_reg((yuv_offset[next_dma_frame] + IVTV_YUV_BUFFER_UV_OFFSET) >> 4, 0x838);
849 				next_dma_frame = (next_dma_frame + 1) % IVTV_YUV_BUFFERS;
850 				atomic_set(&yi->next_dma_frame, next_dma_frame);
851 				yi->fields_lapsed = -1;
852 				yi->running = 1;
853 			}
854 		}
855 	}
856 	if (frame != (itv->last_vsync_field & 1)) {
857 		static const struct v4l2_event evtop = {
858 			.type = V4L2_EVENT_VSYNC,
859 			.u.vsync.field = V4L2_FIELD_TOP,
860 		};
861 		static const struct v4l2_event evbottom = {
862 			.type = V4L2_EVENT_VSYNC,
863 			.u.vsync.field = V4L2_FIELD_BOTTOM,
864 		};
865 		struct ivtv_stream *s = ivtv_get_output_stream(itv);
866 
867 		itv->last_vsync_field += 1;
868 		if (frame == 0) {
869 			clear_bit(IVTV_F_I_VALID_DEC_TIMINGS, &itv->i_flags);
870 			clear_bit(IVTV_F_I_EV_VSYNC_FIELD, &itv->i_flags);
871 		}
872 		else {
873 			set_bit(IVTV_F_I_EV_VSYNC_FIELD, &itv->i_flags);
874 		}
875 		if (test_bit(IVTV_F_I_EV_VSYNC_ENABLED, &itv->i_flags)) {
876 			set_bit(IVTV_F_I_EV_VSYNC, &itv->i_flags);
877 			wake_up(&itv->event_waitq);
878 			if (s)
879 				wake_up(&s->waitq);
880 		}
881 		if (s && s->vdev.v4l2_dev)
882 			v4l2_event_queue(&s->vdev, frame ? &evtop : &evbottom);
883 		wake_up(&itv->vsync_waitq);
884 
885 		/* Send VBI to saa7127 */
886 		if (frame && (itv->output_mode == OUT_PASSTHROUGH ||
887 			test_bit(IVTV_F_I_UPDATE_WSS, &itv->i_flags) ||
888 			test_bit(IVTV_F_I_UPDATE_VPS, &itv->i_flags) ||
889 			test_bit(IVTV_F_I_UPDATE_CC, &itv->i_flags))) {
890 			set_bit(IVTV_F_I_WORK_HANDLER_VBI, &itv->i_flags);
891 			set_bit(IVTV_F_I_HAVE_WORK, &itv->i_flags);
892 		}
893 
894 		/* Check if we need to update the yuv registers */
895 		if (yi->running && (yi->yuv_forced_update || f->update)) {
896 			if (!f->update) {
897 				last_dma_frame =
898 					(u8)(atomic_read(&yi->next_dma_frame) -
899 						 1) % IVTV_YUV_BUFFERS;
900 				f = &yi->new_frame_info[last_dma_frame];
901 			}
902 
903 			if (f->src_w) {
904 				yi->update_frame = last_dma_frame;
905 				f->update = 0;
906 				yi->yuv_forced_update = 0;
907 				set_bit(IVTV_F_I_WORK_HANDLER_YUV, &itv->i_flags);
908 				set_bit(IVTV_F_I_HAVE_WORK, &itv->i_flags);
909 			}
910 		}
911 
912 		yi->fields_lapsed++;
913 	}
914 }
915 
916 #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)
917 
918 irqreturn_t ivtv_irq_handler(int irq, void *dev_id)
919 {
920 	struct ivtv *itv = (struct ivtv *)dev_id;
921 	u32 combo;
922 	u32 stat;
923 	int i;
924 	u8 vsync_force = 0;
925 
926 	spin_lock(&itv->dma_reg_lock);
927 	/* get contents of irq status register */
928 	stat = read_reg(IVTV_REG_IRQSTATUS);
929 
930 	combo = ~itv->irqmask & stat;
931 
932 	/* Clear out IRQ */
933 	if (combo) write_reg(combo, IVTV_REG_IRQSTATUS);
934 
935 	if (0 == combo) {
936 		/* The vsync interrupt is unusual and clears itself. If we
937 		 * took too long, we may have missed it. Do some checks
938 		 */
939 		if (~itv->irqmask & IVTV_IRQ_DEC_VSYNC) {
940 			/* vsync is enabled, see if we're in a new field */
941 			if ((itv->last_vsync_field & 1) !=
942 			    (read_reg(IVTV_REG_DEC_LINE_FIELD) & 1)) {
943 				/* New field, looks like we missed it */
944 				IVTV_DEBUG_YUV("VSync interrupt missed %d\n",
945 				       read_reg(IVTV_REG_DEC_LINE_FIELD) >> 16);
946 				vsync_force = 1;
947 			}
948 		}
949 
950 		if (!vsync_force) {
951 			/* No Vsync expected, wasn't for us */
952 			spin_unlock(&itv->dma_reg_lock);
953 			return IRQ_NONE;
954 		}
955 	}
956 
957 	/* Exclude interrupts noted below from the output, otherwise the log is flooded with
958 	   these messages */
959 	if (combo & ~0xff6d0400)
960 		IVTV_DEBUG_HI_IRQ("======= valid IRQ bits: 0x%08x ======\n", combo);
961 
962 	if (combo & IVTV_IRQ_DEC_DMA_COMPLETE) {
963 		IVTV_DEBUG_HI_IRQ("DEC DMA COMPLETE\n");
964 	}
965 
966 	if (combo & IVTV_IRQ_DMA_READ) {
967 		ivtv_irq_dma_read(itv);
968 	}
969 
970 	if (combo & IVTV_IRQ_ENC_DMA_COMPLETE) {
971 		ivtv_irq_enc_dma_complete(itv);
972 	}
973 
974 	if (combo & IVTV_IRQ_ENC_PIO_COMPLETE) {
975 		ivtv_irq_enc_pio_complete(itv);
976 	}
977 
978 	if (combo & IVTV_IRQ_DMA_ERR) {
979 		ivtv_irq_dma_err(itv);
980 	}
981 
982 	if (combo & IVTV_IRQ_ENC_START_CAP) {
983 		ivtv_irq_enc_start_cap(itv);
984 	}
985 
986 	if (combo & IVTV_IRQ_ENC_VBI_CAP) {
987 		ivtv_irq_enc_vbi_cap(itv);
988 	}
989 
990 	if (combo & IVTV_IRQ_DEC_VBI_RE_INSERT) {
991 		ivtv_irq_dec_vbi_reinsert(itv);
992 	}
993 
994 	if (combo & IVTV_IRQ_ENC_EOS) {
995 		IVTV_DEBUG_IRQ("ENC EOS\n");
996 		set_bit(IVTV_F_I_EOS, &itv->i_flags);
997 		wake_up(&itv->eos_waitq);
998 	}
999 
1000 	if (combo & IVTV_IRQ_DEC_DATA_REQ) {
1001 		ivtv_irq_dec_data_req(itv);
1002 	}
1003 
1004 	/* Decoder Vertical Sync - We can't rely on 'combo', so check if vsync enabled */
1005 	if (~itv->irqmask & IVTV_IRQ_DEC_VSYNC) {
1006 		ivtv_irq_vsync(itv);
1007 	}
1008 
1009 	if (combo & IVTV_IRQ_ENC_VIM_RST) {
1010 		IVTV_DEBUG_IRQ("VIM RST\n");
1011 		/*ivtv_vapi(itv, CX2341X_ENC_REFRESH_INPUT, 0); */
1012 	}
1013 
1014 	if (combo & IVTV_IRQ_DEC_AUD_MODE_CHG) {
1015 		IVTV_DEBUG_INFO("Stereo mode changed\n");
1016 	}
1017 
1018 	if ((combo & IVTV_IRQ_DMA) && !test_bit(IVTV_F_I_DMA, &itv->i_flags)) {
1019 		itv->irq_rr_idx++;
1020 		for (i = 0; i < IVTV_MAX_STREAMS; i++) {
1021 			int idx = (i + itv->irq_rr_idx) % IVTV_MAX_STREAMS;
1022 			struct ivtv_stream *s = &itv->streams[idx];
1023 
1024 			if (!test_and_clear_bit(IVTV_F_S_DMA_PENDING, &s->s_flags))
1025 				continue;
1026 			if (s->type >= IVTV_DEC_STREAM_TYPE_MPG)
1027 				ivtv_dma_dec_start(s);
1028 			else
1029 				ivtv_dma_enc_start(s);
1030 			break;
1031 		}
1032 
1033 		if (i == IVTV_MAX_STREAMS &&
1034 		    test_bit(IVTV_F_I_UDMA_PENDING, &itv->i_flags))
1035 			ivtv_udma_start(itv);
1036 	}
1037 
1038 	if ((combo & IVTV_IRQ_DMA) && !test_bit(IVTV_F_I_PIO, &itv->i_flags)) {
1039 		itv->irq_rr_idx++;
1040 		for (i = 0; i < IVTV_MAX_STREAMS; i++) {
1041 			int idx = (i + itv->irq_rr_idx) % IVTV_MAX_STREAMS;
1042 			struct ivtv_stream *s = &itv->streams[idx];
1043 
1044 			if (!test_and_clear_bit(IVTV_F_S_PIO_PENDING, &s->s_flags))
1045 				continue;
1046 			if (s->type == IVTV_DEC_STREAM_TYPE_VBI || s->type < IVTV_DEC_STREAM_TYPE_MPG)
1047 				ivtv_dma_enc_start(s);
1048 			break;
1049 		}
1050 	}
1051 
1052 	if (test_and_clear_bit(IVTV_F_I_HAVE_WORK, &itv->i_flags)) {
1053 		kthread_queue_work(&itv->irq_worker, &itv->irq_work);
1054 	}
1055 
1056 	spin_unlock(&itv->dma_reg_lock);
1057 
1058 	/* If we've just handled a 'forced' vsync, it's safest to say it
1059 	 * wasn't ours. Another device may have triggered it at just
1060 	 * the right time.
1061 	 */
1062 	return vsync_force ? IRQ_NONE : IRQ_HANDLED;
1063 }
1064 
1065 void ivtv_unfinished_dma(struct timer_list *t)
1066 {
1067 	struct ivtv *itv = from_timer(itv, t, dma_timer);
1068 
1069 	if (!test_bit(IVTV_F_I_DMA, &itv->i_flags))
1070 		return;
1071 	IVTV_ERR("DMA TIMEOUT %08x %d\n", read_reg(IVTV_REG_DMASTATUS), itv->cur_dma_stream);
1072 
1073 	write_reg(read_reg(IVTV_REG_DMASTATUS) & 3, IVTV_REG_DMASTATUS);
1074 	clear_bit(IVTV_F_I_UDMA, &itv->i_flags);
1075 	clear_bit(IVTV_F_I_DMA, &itv->i_flags);
1076 	itv->cur_dma_stream = -1;
1077 	wake_up(&itv->dma_waitq);
1078 }
1079