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path: root/drivers/media/platform/vivid/vivid-vbi-gen.c
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Diffstat (limited to 'drivers/media/platform/vivid/vivid-vbi-gen.c')
-rw-r--r--drivers/media/platform/vivid/vivid-vbi-gen.c323
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;
+ }
+}

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