diff options
Diffstat (limited to 'drivers/media/platform/vivid/vivid-vbi-gen.c')
-rw-r--r-- | drivers/media/platform/vivid/vivid-vbi-gen.c | 323 |
1 files changed, 323 insertions, 0 deletions
diff --git a/drivers/media/platform/vivid/vivid-vbi-gen.c b/drivers/media/platform/vivid/vivid-vbi-gen.c new file mode 100644 index 0000000..a2159de --- /dev/null +++ b/drivers/media/platform/vivid/vivid-vbi-gen.c @@ -0,0 +1,323 @@ +/* + * vivid-vbi-gen.c - vbi generator support functions. + * + * Copyright 2014 Cisco Systems, Inc. and/or its affiliates. All rights reserved. + * + * This program is free software; you may redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#include <linux/errno.h> +#include <linux/kernel.h> +#include <linux/ktime.h> +#include <linux/string.h> +#include <linux/videodev2.h> + +#include "vivid-vbi-gen.h" + +static void wss_insert(u8 *wss, u32 val, unsigned size) +{ + while (size--) + *wss++ = (val & (1 << size)) ? 0xc0 : 0x10; +} + +static void vivid_vbi_gen_wss_raw(const struct v4l2_sliced_vbi_data *data, + u8 *buf, unsigned sampling_rate) +{ + const unsigned rate = 5000000; /* WSS has a 5 MHz transmission rate */ + u8 wss[29 + 24 + 24 + 24 + 18 + 18] = { 0 }; + const unsigned zero = 0x07; + const unsigned one = 0x38; + unsigned bit = 0; + u16 wss_data; + int i; + + wss_insert(wss + bit, 0x1f1c71c7, 29); bit += 29; + wss_insert(wss + bit, 0x1e3c1f, 24); bit += 24; + + wss_data = (data->data[1] << 8) | data->data[0]; + for (i = 0; i <= 13; i++, bit += 6) + wss_insert(wss + bit, (wss_data & (1 << i)) ? one : zero, 6); + + for (i = 0, bit = 0; bit < sizeof(wss); bit++) { + unsigned n = ((bit + 1) * sampling_rate) / rate; + + while (i < n) + buf[i++] = wss[bit]; + } +} + +static void vivid_vbi_gen_teletext_raw(const struct v4l2_sliced_vbi_data *data, + u8 *buf, unsigned sampling_rate) +{ + const unsigned rate = 6937500 / 10; /* Teletext has a 6.9375 MHz transmission rate */ + u8 teletext[45] = { 0x55, 0x55, 0x27 }; + unsigned bit = 0; + int i; + + memcpy(teletext + 3, data->data, sizeof(teletext) - 3); + /* prevents 32 bit overflow */ + sampling_rate /= 10; + + for (i = 0, bit = 0; bit < sizeof(teletext) * 8; bit++) { + unsigned n = ((bit + 1) * sampling_rate) / rate; + u8 val = (teletext[bit / 8] & (1 << (bit & 7))) ? 0xc0 : 0x10; + + while (i < n) + buf[i++] = val; + } +} + +static void cc_insert(u8 *cc, u8 ch) +{ + unsigned tot = 0; + unsigned i; + + for (i = 0; i < 7; i++) { + cc[2 * i] = cc[2 * i + 1] = (ch & (1 << i)) ? 1 : 0; + tot += cc[2 * i]; + } + cc[14] = cc[15] = !(tot & 1); +} + +#define CC_PREAMBLE_BITS (14 + 4 + 2) + +static void vivid_vbi_gen_cc_raw(const struct v4l2_sliced_vbi_data *data, + u8 *buf, unsigned sampling_rate) +{ + const unsigned rate = 1000000; /* CC has a 1 MHz transmission rate */ + + u8 cc[CC_PREAMBLE_BITS + 2 * 16] = { + /* Clock run-in: 7 cycles */ + 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, + /* 2 cycles of 0 */ + 0, 0, 0, 0, + /* Start bit of 1 (each bit is two cycles) */ + 1, 1 + }; + unsigned bit, i; + + cc_insert(cc + CC_PREAMBLE_BITS, data->data[0]); + cc_insert(cc + CC_PREAMBLE_BITS + 16, data->data[1]); + + for (i = 0, bit = 0; bit < sizeof(cc); bit++) { + unsigned n = ((bit + 1) * sampling_rate) / rate; + + while (i < n) + buf[i++] = cc[bit] ? 0xc0 : 0x10; + } +} + +void vivid_vbi_gen_raw(const struct vivid_vbi_gen_data *vbi, + const struct v4l2_vbi_format *vbi_fmt, u8 *buf) +{ + unsigned idx; + + for (idx = 0; idx < 25; idx++) { + const struct v4l2_sliced_vbi_data *data = vbi->data + idx; + unsigned start_2nd_field; + unsigned line = data->line; + u8 *linebuf = buf; + + start_2nd_field = (data->id & V4L2_SLICED_VBI_525) ? 263 : 313; + if (data->field) + line += start_2nd_field; + line -= vbi_fmt->start[data->field]; + + if (vbi_fmt->flags & V4L2_VBI_INTERLACED) + linebuf += (line * 2 + data->field) * + vbi_fmt->samples_per_line; + else + linebuf += (line + data->field * vbi_fmt->count[0]) * + vbi_fmt->samples_per_line; + if (data->id == V4L2_SLICED_CAPTION_525) + vivid_vbi_gen_cc_raw(data, linebuf, vbi_fmt->sampling_rate); + else if (data->id == V4L2_SLICED_WSS_625) + vivid_vbi_gen_wss_raw(data, linebuf, vbi_fmt->sampling_rate); + else if (data->id == V4L2_SLICED_TELETEXT_B) + vivid_vbi_gen_teletext_raw(data, linebuf, vbi_fmt->sampling_rate); + } +} + +static const u8 vivid_cc_sequence1[30] = { + 0x14, 0x20, /* Resume Caption Loading */ + 'H', 'e', + 'l', 'l', + 'o', ' ', + 'w', 'o', + 'r', 'l', + 'd', '!', + 0x14, 0x2f, /* End of Caption */ +}; + +static const u8 vivid_cc_sequence2[30] = { + 0x14, 0x20, /* Resume Caption Loading */ + 'C', 'l', + 'o', 's', + 'e', 'd', + ' ', 'c', + 'a', 'p', + 't', 'i', + 'o', 'n', + 's', ' ', + 't', 'e', + 's', 't', + 0x14, 0x2f, /* End of Caption */ +}; + +static u8 calc_parity(u8 val) +{ + unsigned i; + unsigned tot = 0; + + for (i = 0; i < 7; i++) + tot += (val & (1 << i)) ? 1 : 0; + return val | ((tot & 1) ? 0 : 0x80); +} + +static void vivid_vbi_gen_set_time_of_day(u8 *packet) +{ + struct tm tm; + u8 checksum, i; + + time_to_tm(get_seconds(), 0, &tm); + packet[0] = calc_parity(0x07); + packet[1] = calc_parity(0x01); + packet[2] = calc_parity(0x40 | tm.tm_min); + packet[3] = calc_parity(0x40 | tm.tm_hour); + packet[4] = calc_parity(0x40 | tm.tm_mday); + if (tm.tm_mday == 1 && tm.tm_mon == 2 && + sys_tz.tz_minuteswest > tm.tm_min + tm.tm_hour * 60) + packet[4] = calc_parity(0x60 | tm.tm_mday); + packet[5] = calc_parity(0x40 | (1 + tm.tm_mon)); + packet[6] = calc_parity(0x40 | (1 + tm.tm_wday)); + packet[7] = calc_parity(0x40 | ((tm.tm_year - 90) & 0x3f)); + packet[8] = calc_parity(0x0f); + for (checksum = i = 0; i <= 8; i++) + checksum += packet[i] & 0x7f; + packet[9] = calc_parity(0x100 - checksum); + checksum = 0; + packet[10] = calc_parity(0x07); + packet[11] = calc_parity(0x04); + if (sys_tz.tz_minuteswest >= 0) + packet[12] = calc_parity(0x40 | ((sys_tz.tz_minuteswest / 60) & 0x1f)); + else + packet[12] = calc_parity(0x40 | ((24 + sys_tz.tz_minuteswest / 60) & 0x1f)); + packet[13] = calc_parity(0); + packet[14] = calc_parity(0x0f); + for (checksum = 0, i = 10; i <= 14; i++) + checksum += packet[i] & 0x7f; + packet[15] = calc_parity(0x100 - checksum); +} + +static const u8 hamming[16] = { + 0x15, 0x02, 0x49, 0x5e, 0x64, 0x73, 0x38, 0x2f, + 0xd0, 0xc7, 0x8c, 0x9b, 0xa1, 0xb6, 0xfd, 0xea +}; + +static void vivid_vbi_gen_teletext(u8 *packet, unsigned line, unsigned frame) +{ + unsigned offset = 2; + unsigned i; + + packet[0] = hamming[1 + ((line & 1) << 3)]; + packet[1] = hamming[line >> 1]; + memset(packet + 2, 0x20, 40); + if (line == 0) { + /* subcode */ + packet[2] = hamming[frame % 10]; + packet[3] = hamming[frame / 10]; + packet[4] = hamming[0]; + packet[5] = hamming[0]; + packet[6] = hamming[0]; + packet[7] = hamming[0]; + packet[8] = hamming[0]; + packet[9] = hamming[1]; + offset = 10; + } + packet += offset; + memcpy(packet, "Page: 100 Row: 10", 17); + packet[7] = '0' + frame / 10; + packet[8] = '0' + frame % 10; + packet[15] = '0' + line / 10; + packet[16] = '0' + line % 10; + for (i = 0; i < 42 - offset; i++) + packet[i] = calc_parity(packet[i]); +} + +void vivid_vbi_gen_sliced(struct vivid_vbi_gen_data *vbi, + bool is_60hz, unsigned seqnr) +{ + struct v4l2_sliced_vbi_data *data0 = vbi->data; + struct v4l2_sliced_vbi_data *data1 = vbi->data + 1; + unsigned frame = seqnr % 60; + + memset(vbi->data, 0, sizeof(vbi->data)); + + if (!is_60hz) { + unsigned i; + + for (i = 0; i <= 11; i++) { + data0->id = V4L2_SLICED_TELETEXT_B; + data0->line = 7 + i; + vivid_vbi_gen_teletext(data0->data, i, frame); + data0++; + } + data0->id = V4L2_SLICED_WSS_625; + data0->line = 23; + /* 4x3 video aspect ratio */ + data0->data[0] = 0x08; + data0++; + for (i = 0; i <= 11; i++) { + data0->id = V4L2_SLICED_TELETEXT_B; + data0->field = 1; + data0->line = 7 + i; + vivid_vbi_gen_teletext(data0->data, 12 + i, frame); + data0++; + } + return; + } + + data0->id = V4L2_SLICED_CAPTION_525; + data0->line = 21; + data1->id = V4L2_SLICED_CAPTION_525; + data1->field = 1; + data1->line = 21; + + if (frame < 15) { + data0->data[0] = calc_parity(vivid_cc_sequence1[2 * frame]); + data0->data[1] = calc_parity(vivid_cc_sequence1[2 * frame + 1]); + } else if (frame >= 30 && frame < 45) { + frame -= 30; + data0->data[0] = calc_parity(vivid_cc_sequence2[2 * frame]); + data0->data[1] = calc_parity(vivid_cc_sequence2[2 * frame + 1]); + } else { + data0->data[0] = calc_parity(0); + data0->data[1] = calc_parity(0); + } + + frame = seqnr % (30 * 60); + switch (frame) { + case 0: + vivid_vbi_gen_set_time_of_day(vbi->time_of_day_packet); + /* fall through */ + case 1 ... 7: + data1->data[0] = vbi->time_of_day_packet[frame * 2]; + data1->data[1] = vbi->time_of_day_packet[frame * 2 + 1]; + break; + default: + data1->data[0] = calc_parity(0); + data1->data[1] = calc_parity(0); + break; + } +} |