[go: nahoru, domu]

1/*
2
3    bttv - Bt848 frame grabber driver
4    vbi interface
5
6    (c) 2002 Gerd Knorr <kraxel@bytesex.org>
7
8    Copyright (C) 2005, 2006 Michael H. Schimek <mschimek@gmx.at>
9    Sponsored by OPQ Systems AB
10
11    This program is free software; you can redistribute it and/or modify
12    it under the terms of the GNU General Public License as published by
13    the Free Software Foundation; either version 2 of the License, or
14    (at your option) any later version.
15
16    This program is distributed in the hope that it will be useful,
17    but WITHOUT ANY WARRANTY; without even the implied warranty of
18    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
19    GNU General Public License for more details.
20
21    You should have received a copy of the GNU General Public License
22    along with this program; if not, write to the Free Software
23    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24*/
25
26#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
27
28#include <linux/module.h>
29#include <linux/errno.h>
30#include <linux/fs.h>
31#include <linux/kernel.h>
32#include <linux/interrupt.h>
33#include <linux/kdev_t.h>
34#include <media/v4l2-ioctl.h>
35#include <asm/io.h>
36#include "bttvp.h"
37
38/* Offset from line sync pulse leading edge (0H) to start of VBI capture,
39   in fCLKx2 pixels.  According to the datasheet, VBI capture starts
40   VBI_HDELAY fCLKx1 pixels from the tailing edgeof /HRESET, and /HRESET
41   is 64 fCLKx1 pixels wide.  VBI_HDELAY is set to 0, so this should be
42   (64 + 0) * 2 = 128 fCLKx2 pixels.  But it's not!  The datasheet is
43   Just Plain Wrong.  The real value appears to be different for
44   different revisions of the bt8x8 chips, and to be affected by the
45   horizontal scaling factor.  Experimentally, the value is measured
46   to be about 244.  */
47#define VBI_OFFSET 244
48
49/* 2048 for compatibility with earlier driver versions. The driver
50   really stores 1024 + tvnorm->vbipack * 4 samples per line in the
51   buffer. Note tvnorm->vbipack is <= 0xFF (limit of VBIPACK_LO + HI
52   is 0x1FF DWORDs) and VBI read()s store a frame counter in the last
53   four bytes of the VBI image. */
54#define VBI_BPL 2048
55
56/* Compatibility. */
57#define VBI_DEFLINES 16
58
59static unsigned int vbibufs = 4;
60static unsigned int vbi_debug;
61
62module_param(vbibufs,   int, 0444);
63module_param(vbi_debug, int, 0644);
64MODULE_PARM_DESC(vbibufs,"number of vbi buffers, range 2-32, default 4");
65MODULE_PARM_DESC(vbi_debug,"vbi code debug messages, default is 0 (no)");
66
67#ifdef dprintk
68# undef dprintk
69#endif
70#define dprintk(fmt, ...)						\
71do {									\
72	if (vbi_debug)							\
73		pr_debug("%d: " fmt, btv->c.nr, ##__VA_ARGS__);		\
74} while (0)
75
76#define IMAGE_SIZE(fmt) \
77	(((fmt)->count[0] + (fmt)->count[1]) * (fmt)->samples_per_line)
78
79/* ----------------------------------------------------------------------- */
80/* vbi risc code + mm                                                      */
81
82static int vbi_buffer_setup(struct videobuf_queue *q,
83			    unsigned int *count, unsigned int *size)
84{
85	struct bttv_fh *fh = q->priv_data;
86	struct bttv *btv = fh->btv;
87
88	if (0 == *count)
89		*count = vbibufs;
90
91	*size = IMAGE_SIZE(&fh->vbi_fmt.fmt);
92
93	dprintk("setup: samples=%u start=%d,%d count=%u,%u\n",
94		fh->vbi_fmt.fmt.samples_per_line,
95		fh->vbi_fmt.fmt.start[0],
96		fh->vbi_fmt.fmt.start[1],
97		fh->vbi_fmt.fmt.count[0],
98		fh->vbi_fmt.fmt.count[1]);
99
100	return 0;
101}
102
103static int vbi_buffer_prepare(struct videobuf_queue *q,
104			      struct videobuf_buffer *vb,
105			      enum v4l2_field field)
106{
107	struct bttv_fh *fh = q->priv_data;
108	struct bttv *btv = fh->btv;
109	struct bttv_buffer *buf = container_of(vb,struct bttv_buffer,vb);
110	const struct bttv_tvnorm *tvnorm;
111	unsigned int skip_lines0, skip_lines1, min_vdelay;
112	int redo_dma_risc;
113	int rc;
114
115	buf->vb.size = IMAGE_SIZE(&fh->vbi_fmt.fmt);
116	if (0 != buf->vb.baddr  &&  buf->vb.bsize < buf->vb.size)
117		return -EINVAL;
118
119	tvnorm = fh->vbi_fmt.tvnorm;
120
121	/* There's no VBI_VDELAY register, RISC must skip the lines
122	   we don't want. With default parameters we skip zero lines
123	   as earlier driver versions did. The driver permits video
124	   standard changes while capturing, so we use vbi_fmt.tvnorm
125	   instead of btv->tvnorm to skip zero lines after video
126	   standard changes as well. */
127
128	skip_lines0 = 0;
129	skip_lines1 = 0;
130
131	if (fh->vbi_fmt.fmt.count[0] > 0)
132		skip_lines0 = max(0, (fh->vbi_fmt.fmt.start[0]
133				      - tvnorm->vbistart[0]));
134	if (fh->vbi_fmt.fmt.count[1] > 0)
135		skip_lines1 = max(0, (fh->vbi_fmt.fmt.start[1]
136				      - tvnorm->vbistart[1]));
137
138	redo_dma_risc = 0;
139
140	if (buf->vbi_skip[0] != skip_lines0 ||
141	    buf->vbi_skip[1] != skip_lines1 ||
142	    buf->vbi_count[0] != fh->vbi_fmt.fmt.count[0] ||
143	    buf->vbi_count[1] != fh->vbi_fmt.fmt.count[1]) {
144		buf->vbi_skip[0] = skip_lines0;
145		buf->vbi_skip[1] = skip_lines1;
146		buf->vbi_count[0] = fh->vbi_fmt.fmt.count[0];
147		buf->vbi_count[1] = fh->vbi_fmt.fmt.count[1];
148		redo_dma_risc = 1;
149	}
150
151	if (VIDEOBUF_NEEDS_INIT == buf->vb.state) {
152		redo_dma_risc = 1;
153		if (0 != (rc = videobuf_iolock(q, &buf->vb, NULL)))
154			goto fail;
155	}
156
157	if (redo_dma_risc) {
158		unsigned int bpl, padding, offset;
159		struct videobuf_dmabuf *dma=videobuf_to_dma(&buf->vb);
160
161		bpl = 2044; /* max. vbipack */
162		padding = VBI_BPL - bpl;
163
164		if (fh->vbi_fmt.fmt.count[0] > 0) {
165			rc = bttv_risc_packed(btv, &buf->top,
166					      dma->sglist,
167					      /* offset */ 0, bpl,
168					      padding, skip_lines0,
169					      fh->vbi_fmt.fmt.count[0]);
170			if (0 != rc)
171				goto fail;
172		}
173
174		if (fh->vbi_fmt.fmt.count[1] > 0) {
175			offset = fh->vbi_fmt.fmt.count[0] * VBI_BPL;
176
177			rc = bttv_risc_packed(btv, &buf->bottom,
178					      dma->sglist,
179					      offset, bpl,
180					      padding, skip_lines1,
181					      fh->vbi_fmt.fmt.count[1]);
182			if (0 != rc)
183				goto fail;
184		}
185	}
186
187	/* VBI capturing ends at VDELAY, start of video capturing,
188	   no matter where the RISC program ends. VDELAY minimum is 2,
189	   bounds.top is the corresponding first field line number
190	   times two. VDELAY counts half field lines. */
191	min_vdelay = MIN_VDELAY;
192	if (fh->vbi_fmt.end >= tvnorm->cropcap.bounds.top)
193		min_vdelay += fh->vbi_fmt.end - tvnorm->cropcap.bounds.top;
194
195	/* For bttv_buffer_activate_vbi(). */
196	buf->geo.vdelay = min_vdelay;
197
198	buf->vb.state = VIDEOBUF_PREPARED;
199	buf->vb.field = field;
200	dprintk("buf prepare %p: top=%p bottom=%p field=%s\n",
201		vb, &buf->top, &buf->bottom,
202		v4l2_field_names[buf->vb.field]);
203	return 0;
204
205 fail:
206	bttv_dma_free(q,btv,buf);
207	return rc;
208}
209
210static void
211vbi_buffer_queue(struct videobuf_queue *q, struct videobuf_buffer *vb)
212{
213	struct bttv_fh *fh = q->priv_data;
214	struct bttv *btv = fh->btv;
215	struct bttv_buffer *buf = container_of(vb,struct bttv_buffer,vb);
216
217	dprintk("queue %p\n",vb);
218	buf->vb.state = VIDEOBUF_QUEUED;
219	list_add_tail(&buf->vb.queue,&btv->vcapture);
220	if (NULL == btv->cvbi) {
221		fh->btv->loop_irq |= 4;
222		bttv_set_dma(btv,0x0c);
223	}
224}
225
226static void vbi_buffer_release(struct videobuf_queue *q, struct videobuf_buffer *vb)
227{
228	struct bttv_fh *fh = q->priv_data;
229	struct bttv *btv = fh->btv;
230	struct bttv_buffer *buf = container_of(vb,struct bttv_buffer,vb);
231
232	dprintk("free %p\n",vb);
233	bttv_dma_free(q,fh->btv,buf);
234}
235
236struct videobuf_queue_ops bttv_vbi_qops = {
237	.buf_setup    = vbi_buffer_setup,
238	.buf_prepare  = vbi_buffer_prepare,
239	.buf_queue    = vbi_buffer_queue,
240	.buf_release  = vbi_buffer_release,
241};
242
243/* ----------------------------------------------------------------------- */
244
245static int try_fmt(struct v4l2_vbi_format *f, const struct bttv_tvnorm *tvnorm,
246			__s32 crop_start)
247{
248	__s32 min_start, max_start, max_end, f2_offset;
249	unsigned int i;
250
251	/* For compatibility with earlier driver versions we must pretend
252	   the VBI and video capture window may overlap. In reality RISC
253	   magic aborts VBI capturing at the first line of video capturing,
254	   leaving the rest of the buffer unchanged, usually all zero.
255	   VBI capturing must always start before video capturing. >> 1
256	   because cropping counts field lines times two. */
257	min_start = tvnorm->vbistart[0];
258	max_start = (crop_start >> 1) - 1;
259	max_end = (tvnorm->cropcap.bounds.top
260		   + tvnorm->cropcap.bounds.height) >> 1;
261
262	if (min_start > max_start)
263		return -EBUSY;
264
265	BUG_ON(max_start >= max_end);
266
267	f->sampling_rate    = tvnorm->Fsc;
268	f->samples_per_line = VBI_BPL;
269	f->sample_format    = V4L2_PIX_FMT_GREY;
270	f->offset           = VBI_OFFSET;
271
272	f2_offset = tvnorm->vbistart[1] - tvnorm->vbistart[0];
273
274	for (i = 0; i < 2; ++i) {
275		if (0 == f->count[i]) {
276			/* No data from this field. We leave f->start[i]
277			   alone because VIDIOCSVBIFMT is w/o and EINVALs
278			   when a driver does not support exactly the
279			   requested parameters. */
280		} else {
281			s64 start, count;
282
283			start = clamp(f->start[i], min_start, max_start);
284			/* s64 to prevent overflow. */
285			count = (s64) f->start[i] + f->count[i] - start;
286			f->start[i] = start;
287			f->count[i] = clamp(count, (s64) 1,
288					    max_end - start);
289		}
290
291		min_start += f2_offset;
292		max_start += f2_offset;
293		max_end += f2_offset;
294	}
295
296	if (0 == (f->count[0] | f->count[1])) {
297		/* As in earlier driver versions. */
298		f->start[0] = tvnorm->vbistart[0];
299		f->start[1] = tvnorm->vbistart[1];
300		f->count[0] = 1;
301		f->count[1] = 1;
302	}
303
304	f->flags = 0;
305
306	f->reserved[0] = 0;
307	f->reserved[1] = 0;
308
309	return 0;
310}
311
312int bttv_try_fmt_vbi_cap(struct file *file, void *f, struct v4l2_format *frt)
313{
314	struct bttv_fh *fh = f;
315	struct bttv *btv = fh->btv;
316	const struct bttv_tvnorm *tvnorm;
317	__s32 crop_start;
318
319	mutex_lock(&btv->lock);
320
321	tvnorm = &bttv_tvnorms[btv->tvnorm];
322	crop_start = btv->crop_start;
323
324	mutex_unlock(&btv->lock);
325
326	return try_fmt(&frt->fmt.vbi, tvnorm, crop_start);
327}
328
329
330int bttv_s_fmt_vbi_cap(struct file *file, void *f, struct v4l2_format *frt)
331{
332	struct bttv_fh *fh = f;
333	struct bttv *btv = fh->btv;
334	const struct bttv_tvnorm *tvnorm;
335	__s32 start1, end;
336	int rc;
337
338	mutex_lock(&btv->lock);
339
340	rc = -EBUSY;
341	if (fh->resources & RESOURCE_VBI)
342		goto fail;
343
344	tvnorm = &bttv_tvnorms[btv->tvnorm];
345
346	rc = try_fmt(&frt->fmt.vbi, tvnorm, btv->crop_start);
347	if (0 != rc)
348		goto fail;
349
350	start1 = frt->fmt.vbi.start[1] - tvnorm->vbistart[1] +
351		tvnorm->vbistart[0];
352
353	/* First possible line of video capturing. Should be
354	   max(f->start[0] + f->count[0], start1 + f->count[1]) * 2
355	   when capturing both fields. But for compatibility we must
356	   pretend the VBI and video capture window may overlap,
357	   so end = start + 1, the lowest possible value, times two
358	   because vbi_fmt.end counts field lines times two. */
359	end = max(frt->fmt.vbi.start[0], start1) * 2 + 2;
360
361	mutex_lock(&fh->vbi.vb_lock);
362
363	fh->vbi_fmt.fmt    = frt->fmt.vbi;
364	fh->vbi_fmt.tvnorm = tvnorm;
365	fh->vbi_fmt.end    = end;
366
367	mutex_unlock(&fh->vbi.vb_lock);
368
369	rc = 0;
370
371 fail:
372	mutex_unlock(&btv->lock);
373
374	return rc;
375}
376
377
378int bttv_g_fmt_vbi_cap(struct file *file, void *f, struct v4l2_format *frt)
379{
380	struct bttv_fh *fh = f;
381	const struct bttv_tvnorm *tvnorm;
382
383	frt->fmt.vbi = fh->vbi_fmt.fmt;
384
385	tvnorm = &bttv_tvnorms[fh->btv->tvnorm];
386
387	if (tvnorm != fh->vbi_fmt.tvnorm) {
388		__s32 max_end;
389		unsigned int i;
390
391		/* As in vbi_buffer_prepare() this imitates the
392		   behaviour of earlier driver versions after video
393		   standard changes, with default parameters anyway. */
394
395		max_end = (tvnorm->cropcap.bounds.top
396			   + tvnorm->cropcap.bounds.height) >> 1;
397
398		frt->fmt.vbi.sampling_rate = tvnorm->Fsc;
399
400		for (i = 0; i < 2; ++i) {
401			__s32 new_start;
402
403			new_start = frt->fmt.vbi.start[i]
404				+ tvnorm->vbistart[i]
405				- fh->vbi_fmt.tvnorm->vbistart[i];
406
407			frt->fmt.vbi.start[i] = min(new_start, max_end - 1);
408			frt->fmt.vbi.count[i] =
409				min((__s32) frt->fmt.vbi.count[i],
410					  max_end - frt->fmt.vbi.start[i]);
411
412			max_end += tvnorm->vbistart[1]
413				- tvnorm->vbistart[0];
414		}
415	}
416	return 0;
417}
418
419void bttv_vbi_fmt_reset(struct bttv_vbi_fmt *f, unsigned int norm)
420{
421	const struct bttv_tvnorm *tvnorm;
422	unsigned int real_samples_per_line;
423	unsigned int real_count;
424
425	tvnorm = &bttv_tvnorms[norm];
426
427	f->fmt.sampling_rate    = tvnorm->Fsc;
428	f->fmt.samples_per_line = VBI_BPL;
429	f->fmt.sample_format    = V4L2_PIX_FMT_GREY;
430	f->fmt.offset           = VBI_OFFSET;
431	f->fmt.start[0]		= tvnorm->vbistart[0];
432	f->fmt.start[1]		= tvnorm->vbistart[1];
433	f->fmt.count[0]		= VBI_DEFLINES;
434	f->fmt.count[1]		= VBI_DEFLINES;
435	f->fmt.flags            = 0;
436	f->fmt.reserved[0]      = 0;
437	f->fmt.reserved[1]      = 0;
438
439	/* For compatibility the buffer size must be 2 * VBI_DEFLINES *
440	   VBI_BPL regardless of the current video standard. */
441	real_samples_per_line   = 1024 + tvnorm->vbipack * 4;
442	real_count              = ((tvnorm->cropcap.defrect.top >> 1)
443				   - tvnorm->vbistart[0]);
444
445	BUG_ON(real_samples_per_line > VBI_BPL);
446	BUG_ON(real_count > VBI_DEFLINES);
447
448	f->tvnorm               = tvnorm;
449
450	/* See bttv_vbi_fmt_set(). */
451	f->end                  = tvnorm->vbistart[0] * 2 + 2;
452}
453
454/* ----------------------------------------------------------------------- */
455/*
456 * Local variables:
457 * c-basic-offset: 8
458 * End:
459 */
460