1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * cx18 Vertical Blank Interval support functions
4 *
5 * Derived from ivtv-vbi.c
6 *
7 * Copyright (C) 2007 Hans Verkuil <hverkuil@xs4all.nl>
8 */
9
10 #include "cx18-driver.h"
11 #include "cx18-vbi.h"
12 #include "cx18-ioctl.h"
13 #include "cx18-queue.h"
14
15 /*
16 * Raster Reference/Protection (RP) bytes, used in Start/End Active
17 * Video codes emitted from the digitzer in VIP 1.x mode, that flag the start
18 * of VBI sample or VBI ancillary data regions in the digital ratser line.
19 *
20 * Task FieldEven VerticalBlank HorizontalBlank 0 0 0 0
21 */
22 static const u8 raw_vbi_sav_rp[2] = { 0x20, 0x60 }; /* __V_, _FV_ */
23 static const u8 sliced_vbi_eav_rp[2] = { 0xb0, 0xf0 }; /* T_VH, TFVH */
24
copy_vbi_data(struct cx18 * cx,int lines,u32 pts_stamp)25 static void copy_vbi_data(struct cx18 *cx, int lines, u32 pts_stamp)
26 {
27 int line = 0;
28 int i;
29 u32 linemask[2] = { 0, 0 };
30 unsigned short size;
31 static const u8 mpeg_hdr_data[] = {
32 /* MPEG-2 Program Pack */
33 0x00, 0x00, 0x01, 0xba, /* Prog Pack start code */
34 0x44, 0x00, 0x0c, 0x66, 0x24, 0x01, /* SCR, SCR Ext, markers */
35 0x01, 0xd1, 0xd3, /* Mux Rate, markers */
36 0xfa, 0xff, 0xff, /* Res, Suff cnt, Stuff */
37 /* MPEG-2 Private Stream 1 PES Packet */
38 0x00, 0x00, 0x01, 0xbd, /* Priv Stream 1 start */
39 0x00, 0x1a, /* length */
40 0x84, 0x80, 0x07, /* flags, hdr data len */
41 0x21, 0x00, 0x5d, 0x63, 0xa7, /* PTS, markers */
42 0xff, 0xff /* stuffing */
43 };
44 const int sd = sizeof(mpeg_hdr_data); /* start of vbi data */
45 int idx = cx->vbi.frame % CX18_VBI_FRAMES;
46 u8 *dst = &cx->vbi.sliced_mpeg_data[idx][0];
47
48 for (i = 0; i < lines; i++) {
49 struct v4l2_sliced_vbi_data *sdata = cx->vbi.sliced_data + i;
50 int f, l;
51
52 if (sdata->id == 0)
53 continue;
54
55 l = sdata->line - 6;
56 f = sdata->field;
57 if (f)
58 l += 18;
59 if (l < 32)
60 linemask[0] |= (1 << l);
61 else
62 linemask[1] |= (1 << (l - 32));
63 dst[sd + 12 + line * 43] = cx18_service2vbi(sdata->id);
64 memcpy(dst + sd + 12 + line * 43 + 1, sdata->data, 42);
65 line++;
66 }
67 memcpy(dst, mpeg_hdr_data, sizeof(mpeg_hdr_data));
68 if (line == 36) {
69 /* All lines are used, so there is no space for the linemask
70 (the max size of the VBI data is 36 * 43 + 4 bytes).
71 So in this case we use the magic number 'ITV0'. */
72 memcpy(dst + sd, "ITV0", 4);
73 memmove(dst + sd + 4, dst + sd + 12, line * 43);
74 size = 4 + ((43 * line + 3) & ~3);
75 } else {
76 memcpy(dst + sd, "itv0", 4);
77 cpu_to_le32s(&linemask[0]);
78 cpu_to_le32s(&linemask[1]);
79 memcpy(dst + sd + 4, &linemask[0], 8);
80 size = 12 + ((43 * line + 3) & ~3);
81 }
82 dst[4+16] = (size + 10) >> 8;
83 dst[5+16] = (size + 10) & 0xff;
84 dst[9+16] = 0x21 | ((pts_stamp >> 29) & 0x6);
85 dst[10+16] = (pts_stamp >> 22) & 0xff;
86 dst[11+16] = 1 | ((pts_stamp >> 14) & 0xff);
87 dst[12+16] = (pts_stamp >> 7) & 0xff;
88 dst[13+16] = 1 | ((pts_stamp & 0x7f) << 1);
89 cx->vbi.sliced_mpeg_size[idx] = sd + size;
90 }
91
92 /* Compress raw VBI format, removes leading SAV codes and surplus space
93 after the frame. Returns new compressed size. */
94 /* FIXME - this function ignores the input size. */
compress_raw_buf(struct cx18 * cx,u8 * buf,u32 size,u32 hdr_size)95 static u32 compress_raw_buf(struct cx18 *cx, u8 *buf, u32 size, u32 hdr_size)
96 {
97 u32 line_size = VBI_ACTIVE_SAMPLES;
98 u32 lines = cx->vbi.count * 2;
99 u8 *q = buf;
100 u8 *p;
101 int i;
102
103 /* Skip the header */
104 buf += hdr_size;
105
106 for (i = 0; i < lines; i++) {
107 p = buf + i * line_size;
108
109 /* Look for SAV code */
110 if (p[0] != 0xff || p[1] || p[2] ||
111 (p[3] != raw_vbi_sav_rp[0] &&
112 p[3] != raw_vbi_sav_rp[1]))
113 break;
114 if (i == lines - 1) {
115 /* last line is hdr_size bytes short - extrapolate it */
116 memcpy(q, p + 4, line_size - 4 - hdr_size);
117 q += line_size - 4 - hdr_size;
118 p += line_size - hdr_size - 1;
119 memset(q, (int) *p, hdr_size);
120 } else {
121 memcpy(q, p + 4, line_size - 4);
122 q += line_size - 4;
123 }
124 }
125 return lines * (line_size - 4);
126 }
127
compress_sliced_buf(struct cx18 * cx,u8 * buf,u32 size,const u32 hdr_size)128 static u32 compress_sliced_buf(struct cx18 *cx, u8 *buf, u32 size,
129 const u32 hdr_size)
130 {
131 struct v4l2_decode_vbi_line vbi;
132 int i;
133 u32 line = 0;
134 u32 line_size = cx->is_60hz ? VBI_HBLANK_SAMPLES_60HZ
135 : VBI_HBLANK_SAMPLES_50HZ;
136
137 /* find the first valid line */
138 for (i = hdr_size, buf += hdr_size; i < size; i++, buf++) {
139 if (buf[0] == 0xff && !buf[1] && !buf[2] &&
140 (buf[3] == sliced_vbi_eav_rp[0] ||
141 buf[3] == sliced_vbi_eav_rp[1]))
142 break;
143 }
144
145 /*
146 * The last line is short by hdr_size bytes, but for the remaining
147 * checks against size, we pretend that it is not, by counting the
148 * header bytes we knowingly skipped
149 */
150 size -= (i - hdr_size);
151 if (size < line_size)
152 return line;
153
154 for (i = 0; i < size / line_size; i++) {
155 u8 *p = buf + i * line_size;
156
157 /* Look for EAV code */
158 if (p[0] != 0xff || p[1] || p[2] ||
159 (p[3] != sliced_vbi_eav_rp[0] &&
160 p[3] != sliced_vbi_eav_rp[1]))
161 continue;
162 vbi.p = p + 4;
163 v4l2_subdev_call(cx->sd_av, vbi, decode_vbi_line, &vbi);
164 if (vbi.type) {
165 cx->vbi.sliced_data[line].id = vbi.type;
166 cx->vbi.sliced_data[line].field = vbi.is_second_field;
167 cx->vbi.sliced_data[line].line = vbi.line;
168 memcpy(cx->vbi.sliced_data[line].data, vbi.p, 42);
169 line++;
170 }
171 }
172 return line;
173 }
174
_cx18_process_vbi_data(struct cx18 * cx,struct cx18_buffer * buf)175 static void _cx18_process_vbi_data(struct cx18 *cx, struct cx18_buffer *buf)
176 {
177 /*
178 * The CX23418 provides a 12 byte header in its raw VBI buffers to us:
179 * 0x3fffffff [4 bytes of something] [4 byte presentation time stamp]
180 */
181 struct vbi_data_hdr {
182 __be32 magic;
183 __be32 unknown;
184 __be32 pts;
185 } *hdr = (struct vbi_data_hdr *) buf->buf;
186
187 u8 *p = (u8 *) buf->buf;
188 u32 size = buf->bytesused;
189 u32 pts;
190 int lines;
191
192 /*
193 * The CX23418 sends us data that is 32 bit little-endian swapped,
194 * but we want the raw VBI bytes in the order they were in the raster
195 * line. This has a side effect of making the header big endian
196 */
197 cx18_buf_swap(buf);
198
199 /* Raw VBI data */
200 if (cx18_raw_vbi(cx)) {
201
202 size = buf->bytesused =
203 compress_raw_buf(cx, p, size, sizeof(struct vbi_data_hdr));
204
205 /*
206 * Hack needed for compatibility with old VBI software.
207 * Write the frame # at the last 4 bytes of the frame
208 */
209 p += size - 4;
210 memcpy(p, &cx->vbi.frame, 4);
211 cx->vbi.frame++;
212 return;
213 }
214
215 /* Sliced VBI data with data insertion */
216
217 pts = (be32_to_cpu(hdr->magic) == 0x3fffffff) ? be32_to_cpu(hdr->pts)
218 : 0;
219
220 lines = compress_sliced_buf(cx, p, size, sizeof(struct vbi_data_hdr));
221
222 /* always return at least one empty line */
223 if (lines == 0) {
224 cx->vbi.sliced_data[0].id = 0;
225 cx->vbi.sliced_data[0].line = 0;
226 cx->vbi.sliced_data[0].field = 0;
227 lines = 1;
228 }
229 buf->bytesused = size = lines * sizeof(cx->vbi.sliced_data[0]);
230 memcpy(p, &cx->vbi.sliced_data[0], size);
231
232 if (cx->vbi.insert_mpeg)
233 copy_vbi_data(cx, lines, pts);
234 cx->vbi.frame++;
235 }
236
cx18_process_vbi_data(struct cx18 * cx,struct cx18_mdl * mdl,int streamtype)237 void cx18_process_vbi_data(struct cx18 *cx, struct cx18_mdl *mdl,
238 int streamtype)
239 {
240 struct cx18_buffer *buf;
241 u32 orig_used;
242
243 if (streamtype != CX18_ENC_STREAM_TYPE_VBI)
244 return;
245
246 /*
247 * Big assumption here:
248 * Every buffer hooked to the MDL's buf_list is a complete VBI frame
249 * that ends at the end of the buffer.
250 *
251 * To assume anything else would make the code in this file
252 * more complex, or require extra memcpy()'s to make the
253 * buffers satisfy the above assumption. It's just simpler to set
254 * up the encoder buffer transfers to make the assumption true.
255 */
256 list_for_each_entry(buf, &mdl->buf_list, list) {
257 orig_used = buf->bytesused;
258 if (orig_used == 0)
259 break;
260 _cx18_process_vbi_data(cx, buf);
261 mdl->bytesused -= (orig_used - buf->bytesused);
262 }
263 }
264