1/*
2 *  cx18 Vertical Blank Interval support functions
3 *
4 *  Derived from ivtv-vbi.c
5 *
6 *  Copyright (C) 2007  Hans Verkuil <hverkuil@xs4all.nl>
7 *
8 *  This program is free software; you can redistribute it and/or modify
9 *  it under the terms of the GNU General Public License as published by
10 *  the Free Software Foundation; either version 2 of the License, or
11 *  (at your option) any later version.
12 *
13 *  This program is distributed in the hope that it will be useful,
14 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
15 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16 *  GNU General Public License for more details.
17 *
18 *  You should have received a copy of the GNU General Public License
19 *  along with this program; if not, write to the Free Software
20 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
21 *  02111-1307  USA
22 */
23
24#include "cx18-driver.h"
25#include "cx18-vbi.h"
26#include "cx18-ioctl.h"
27#include "cx18-queue.h"
28
29/*
30 * Raster Reference/Protection (RP) bytes, used in Start/End Active
31 * Video codes emitted from the digitzer in VIP 1.x mode, that flag the start
32 * of VBI sample or VBI ancillary data regions in the digitial ratser line.
33 *
34 * Task FieldEven VerticalBlank HorizontalBlank 0 0 0 0
35 */
36static const u8 raw_vbi_sav_rp[2] = { 0x20, 0x60 };    /* __V_, _FV_ */
37static const u8 sliced_vbi_eav_rp[2] = { 0xb0, 0xf0 }; /* T_VH, TFVH */
38
39static void copy_vbi_data(struct cx18 *cx, int lines, u32 pts_stamp)
40{
41	int line = 0;
42	int i;
43	u32 linemask[2] = { 0, 0 };
44	unsigned short size;
45	static const u8 mpeg_hdr_data[] = {
46		/* MPEG-2 Program Pack */
47		0x00, 0x00, 0x01, 0xba,		    /* Prog Pack start code */
48		0x44, 0x00, 0x0c, 0x66, 0x24, 0x01, /* SCR, SCR Ext, markers */
49		0x01, 0xd1, 0xd3,		    /* Mux Rate, markers */
50		0xfa, 0xff, 0xff,		    /* Res, Suff cnt, Stuff */
51		/* MPEG-2 Private Stream 1 PES Packet */
52		0x00, 0x00, 0x01, 0xbd,		    /* Priv Stream 1 start */
53		0x00, 0x1a,			    /* length */
54		0x84, 0x80, 0x07,		    /* flags, hdr data len */
55		0x21, 0x00, 0x5d, 0x63, 0xa7, 	    /* PTS, markers */
56		0xff, 0xff			    /* stuffing */
57	};
58	const int sd = sizeof(mpeg_hdr_data);	/* start of vbi data */
59	int idx = cx->vbi.frame % CX18_VBI_FRAMES;
60	u8 *dst = &cx->vbi.sliced_mpeg_data[idx][0];
61
62	for (i = 0; i < lines; i++) {
63		struct v4l2_sliced_vbi_data *sdata = cx->vbi.sliced_data + i;
64		int f, l;
65
66		if (sdata->id == 0)
67			continue;
68
69		l = sdata->line - 6;
70		f = sdata->field;
71		if (f)
72			l += 18;
73		if (l < 32)
74			linemask[0] |= (1 << l);
75		else
76			linemask[1] |= (1 << (l - 32));
77		dst[sd + 12 + line * 43] = cx18_service2vbi(sdata->id);
78		memcpy(dst + sd + 12 + line * 43 + 1, sdata->data, 42);
79		line++;
80	}
81	memcpy(dst, mpeg_hdr_data, sizeof(mpeg_hdr_data));
82	if (line == 36) {
83		/* All lines are used, so there is no space for the linemask
84		   (the max size of the VBI data is 36 * 43 + 4 bytes).
85		   So in this case we use the magic number 'ITV0'. */
86		memcpy(dst + sd, "ITV0", 4);
87		memmove(dst + sd + 4, dst + sd + 12, line * 43);
88		size = 4 + ((43 * line + 3) & ~3);
89	} else {
90		memcpy(dst + sd, "itv0", 4);
91		cpu_to_le32s(&linemask[0]);
92		cpu_to_le32s(&linemask[1]);
93		memcpy(dst + sd + 4, &linemask[0], 8);
94		size = 12 + ((43 * line + 3) & ~3);
95	}
96	dst[4+16] = (size + 10) >> 8;
97	dst[5+16] = (size + 10) & 0xff;
98	dst[9+16] = 0x21 | ((pts_stamp >> 29) & 0x6);
99	dst[10+16] = (pts_stamp >> 22) & 0xff;
100	dst[11+16] = 1 | ((pts_stamp >> 14) & 0xff);
101	dst[12+16] = (pts_stamp >> 7) & 0xff;
102	dst[13+16] = 1 | ((pts_stamp & 0x7f) << 1);
103	cx->vbi.sliced_mpeg_size[idx] = sd + size;
104}
105
106/* Compress raw VBI format, removes leading SAV codes and surplus space
107   after the frame.  Returns new compressed size. */
108/* FIXME - this function ignores the input size. */
109static u32 compress_raw_buf(struct cx18 *cx, u8 *buf, u32 size, u32 hdr_size)
110{
111	u32 line_size = vbi_active_samples;
112	u32 lines = cx->vbi.count * 2;
113	u8 *q = buf;
114	u8 *p;
115	int i;
116
117	/* Skip the header */
118	buf += hdr_size;
119
120	for (i = 0; i < lines; i++) {
121		p = buf + i * line_size;
122
123		/* Look for SAV code */
124		if (p[0] != 0xff || p[1] || p[2] ||
125		    (p[3] != raw_vbi_sav_rp[0] &&
126		     p[3] != raw_vbi_sav_rp[1]))
127			break;
128		if (i == lines - 1) {
129			/* last line is hdr_size bytes short - extrapolate it */
130			memcpy(q, p + 4, line_size - 4 - hdr_size);
131			q += line_size - 4 - hdr_size;
132			p += line_size - hdr_size - 1;
133			memset(q, (int) *p, hdr_size);
134		} else {
135			memcpy(q, p + 4, line_size - 4);
136			q += line_size - 4;
137		}
138	}
139	return lines * (line_size - 4);
140}
141
142static u32 compress_sliced_buf(struct cx18 *cx, u8 *buf, u32 size,
143			       const u32 hdr_size)
144{
145	struct v4l2_decode_vbi_line vbi;
146	int i;
147	u32 line = 0;
148	u32 line_size = cx->is_60hz ? vbi_hblank_samples_60Hz
149				    : vbi_hblank_samples_50Hz;
150
151	/* find the first valid line */
152	for (i = hdr_size, buf += hdr_size; i < size; i++, buf++) {
153		if (buf[0] == 0xff && !buf[1] && !buf[2] &&
154		    (buf[3] == sliced_vbi_eav_rp[0] ||
155		     buf[3] == sliced_vbi_eav_rp[1]))
156			break;
157	}
158
159	/*
160	 * The last line is short by hdr_size bytes, but for the remaining
161	 * checks against size, we pretend that it is not, by counting the
162	 * header bytes we knowingly skipped
163	 */
164	size -= (i - hdr_size);
165	if (size < line_size)
166		return line;
167
168	for (i = 0; i < size / line_size; i++) {
169		u8 *p = buf + i * line_size;
170
171		/* Look for EAV code  */
172		if (p[0] != 0xff || p[1] || p[2] ||
173		    (p[3] != sliced_vbi_eav_rp[0] &&
174		     p[3] != sliced_vbi_eav_rp[1]))
175			continue;
176		vbi.p = p + 4;
177		v4l2_subdev_call(cx->sd_av, vbi, decode_vbi_line, &vbi);
178		if (vbi.type) {
179			cx->vbi.sliced_data[line].id = vbi.type;
180			cx->vbi.sliced_data[line].field = vbi.is_second_field;
181			cx->vbi.sliced_data[line].line = vbi.line;
182			memcpy(cx->vbi.sliced_data[line].data, vbi.p, 42);
183			line++;
184		}
185	}
186	return line;
187}
188
189static void _cx18_process_vbi_data(struct cx18 *cx, struct cx18_buffer *buf)
190{
191	/*
192	 * The CX23418 provides a 12 byte header in its raw VBI buffers to us:
193	 * 0x3fffffff [4 bytes of something] [4 byte presentation time stamp]
194	 */
195	struct vbi_data_hdr {
196		__be32 magic;
197		__be32 unknown;
198		__be32 pts;
199	} *hdr = (struct vbi_data_hdr *) buf->buf;
200
201	u8 *p = (u8 *) buf->buf;
202	u32 size = buf->bytesused;
203	u32 pts;
204	int lines;
205
206	/*
207	 * The CX23418 sends us data that is 32 bit little-endian swapped,
208	 * but we want the raw VBI bytes in the order they were in the raster
209	 * line.  This has a side effect of making the header big endian
210	 */
211	cx18_buf_swap(buf);
212
213	/* Raw VBI data */
214	if (cx18_raw_vbi(cx)) {
215
216		size = buf->bytesused =
217		     compress_raw_buf(cx, p, size, sizeof(struct vbi_data_hdr));
218
219		/*
220		 * Hack needed for compatibility with old VBI software.
221		 * Write the frame # at the last 4 bytes of the frame
222		 */
223		p += size - 4;
224		memcpy(p, &cx->vbi.frame, 4);
225		cx->vbi.frame++;
226		return;
227	}
228
229	/* Sliced VBI data with data insertion */
230
231	pts = (be32_to_cpu(hdr->magic) == 0x3fffffff) ? be32_to_cpu(hdr->pts)
232						      : 0;
233
234	lines = compress_sliced_buf(cx, p, size, sizeof(struct vbi_data_hdr));
235
236	/* always return at least one empty line */
237	if (lines == 0) {
238		cx->vbi.sliced_data[0].id = 0;
239		cx->vbi.sliced_data[0].line = 0;
240		cx->vbi.sliced_data[0].field = 0;
241		lines = 1;
242	}
243	buf->bytesused = size = lines * sizeof(cx->vbi.sliced_data[0]);
244	memcpy(p, &cx->vbi.sliced_data[0], size);
245
246	if (cx->vbi.insert_mpeg)
247		copy_vbi_data(cx, lines, pts);
248	cx->vbi.frame++;
249}
250
251void cx18_process_vbi_data(struct cx18 *cx, struct cx18_mdl *mdl,
252			   int streamtype)
253{
254	struct cx18_buffer *buf;
255	u32 orig_used;
256
257	if (streamtype != CX18_ENC_STREAM_TYPE_VBI)
258		return;
259
260	/*
261	 * Big assumption here:
262	 * Every buffer hooked to the MDL's buf_list is a complete VBI frame
263	 * that ends at the end of the buffer.
264	 *
265	 * To assume anything else would make the code in this file
266	 * more complex, or require extra memcpy()'s to make the
267	 * buffers satisfy the above assumption.  It's just simpler to set
268	 * up the encoder buffer transfers to make the assumption true.
269	 */
270	list_for_each_entry(buf, &mdl->buf_list, list) {
271		orig_used = buf->bytesused;
272		if (orig_used == 0)
273			break;
274		_cx18_process_vbi_data(cx, buf);
275		mdl->bytesused -= (orig_used - buf->bytesused);
276	}
277}
278