1 files changed, 311 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 000000000..acc98445a
--- /dev/null
+++ b/drivers/media/platform/vivid/vivid-vbi-gen.c
@@ -0,0 +1,311 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * vivid-vbi-gen.c - vbi generator support functions.
+ *
+ * Copyright 2014 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
+ */
+
+#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;
+
+	time64_to_tm(ktime_get_real_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;
+	}
+}