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[mpeg2] Re: Setting Audio, Video, and PCR PIDs
> > After this change, things are working, but I still have a little
> > problem: in my setup, I first run a program that opens /dev/video1, does
> > some ioctl() to configure the stream, and exits; then I run a different
> > program that opens /dev/video1 for reading. With your patch, this does
> > not work because when the second program starts to read from /dev/video1
> > saa6752hs_init() is called with params == NULL, hence it restores all
> > the parameters to the default. I think that adding a
> > i2c_set_clientdata(client, cachedParams);
> > at the end of saa6752hs_init() fixes this problem (at least, it works
> > for me, but I don't know if it is the correct thing to do -- I do not
> > know the i2c stuff well).
>
> Hmm, its supposed to be able to support that (I do something similar). When
> its called with (params!=NULL), it copies them into the cachedParams. When
> its called with (params==NULL), it just uses the cachedParams, as set by
> the previous call. Must be an annoying bug somewhere - I'll see if I can
> spot it.
Hi, found a problem - I had the check for target bitrate and max bit rate the
wrong way round.
Oh, I've also added in that printk we were talking about - moan if
MPEG_SETPARAMS fails since we send the return code to the user app.
Just tested it with a quick program - seems to be preserving the mpeg settings
across multiple open() calls now.
Common subdirectories: saa7134-0.2.12.orig/.tmp_versions and saa7134-0.2.12/.tmp_versions
Common subdirectories: saa7134-0.2.12.orig/doc and saa7134-0.2.12/doc
Common subdirectories: saa7134-0.2.12.orig/linux and saa7134-0.2.12/linux
Common subdirectories: saa7134-0.2.12.orig/media and saa7134-0.2.12/media
diff -Nau saa7134-0.2.12.orig/saa6752hs.c saa7134-0.2.12/saa6752hs.c
--- saa7134-0.2.12.orig/saa6752hs.c 2004-02-22 01:59:35.000000000 +0000
+++ saa7134-0.2.12/saa6752hs.c 2004-05-17 16:07:44.454938784 +0100
@@ -11,6 +11,7 @@
#include <linux/types.h>
#include <linux/videodev.h>
#include <linux/init.h>
+#include <linux/crc32.h>
#if LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0)
#include "i2c-compat.h"
@@ -73,9 +74,9 @@
0x00, 0x01, // program_number(1)
- 0xe0, 0x10, // PMT PID(0x10)
+ 0xe0, 0x00, // PMT PID
- 0x76, 0xf1, 0x44, 0xd1 // CRC32
+ 0x00, 0x00, 0x00, 0x00 // CRC32
};
static u8 PMT[] = {
@@ -83,7 +84,7 @@
0x01, // table number for encoder
0x47, // sync
- 0x40, 0x10, // transport_error_indicator(0), payload_unit_start(1), transport_priority(0), pid(0x10)
+ 0x40, 0x00, // transport_error_indicator(0), payload_unit_start(1), transport_priority(0), pid
0x10, // transport_scrambling_control(00), adaptation_field_control(01), continuity_counter(0)
0x00, // PSI pointer to start of table
@@ -97,22 +98,27 @@
0x00, 0x00, // section_number(0), last_section_number(0)
- 0xe1, 0x04, // PCR_PID (0x104)
+ 0xe0, 0x00, // PCR_PID
0xf0, 0x00, // program_info_length(0)
- 0x02, 0xe1, 0x00, 0xf0, 0x00, // video stream type(2), pid(0x100)
- 0x04, 0xe1, 0x03, 0xf0, 0x00, // audio stream type(4), pid(0x103)
+ 0x02, 0xe0, 0x00, 0xf0, 0x00, // video stream type(2), pid
+ 0x04, 0xe0, 0x00, 0xf0, 0x00, // audio stream type(4), pid
- 0xa1, 0xca, 0x0f, 0x82 // CRC32
+ 0x00, 0x00, 0x00, 0x00 // CRC32
};
static struct mpeg_params mpeg_params_template =
{
- .bitrate_mode = MPEG_BITRATE_MODE_CBR,
- .video_target_bitrate = 5000,
+ .video_bitrate_mode = MPEG_VIDEO_BITRATE_MODE_VBR,
+ .video_target_bitrate = 4000,
+ .video_max_bitrate = 6000,
.audio_bitrate = MPEG_AUDIO_BITRATE_256,
- .total_bitrate = 6000,
+ .total_bitrate = 7000,
+ .pmt_pid = 16,
+ .video_pid = 260,
+ .audio_pid = 256,
+ .pcr_pid = 259,
};
@@ -133,7 +139,7 @@
break;
case SAA6752HS_COMMAND_STOP:
- buf[0] = 0x03;
+ buf[0] = 0x03;
break;
case SAA6752HS_COMMAND_START:
@@ -197,11 +203,11 @@
// set the bitrate mode
buf[0] = 0x71;
- buf[1] = params->bitrate_mode;
+ buf[1] = params->video_bitrate_mode;
i2c_master_send(client, buf, 2);
// set the video bitrate
- if (params->bitrate_mode == MPEG_BITRATE_MODE_VBR) {
+ if (params->video_bitrate_mode == MPEG_VIDEO_BITRATE_MODE_VBR) {
// set the target bitrate
buf[0] = 0x80;
buf[1] = params->video_target_bitrate >> 8;
@@ -239,25 +245,73 @@
static int saa6752hs_init(struct i2c_client* client, struct mpeg_params* params)
{
unsigned char buf[3];
- void *data;
+ struct mpeg_params* cachedParams;
+ u32 crc;
+ unsigned char localPAT[256];
+ unsigned char localPMT[256];
+
+ // grab the previous set of parameters
+ cachedParams = (struct mpeg_params*) i2c_get_clientdata(client);
// check the bitrate parameters first
if (params != NULL) {
- if (params->bitrate_mode >= MPEG_BITRATE_MODE_MAX)
+ unsigned int pmt_pid = 0, pcr_pid = 0, video_pid = 0 , audio_pid = 0;
+
+ // check supplied params are valid
+ if (params->video_bitrate_mode >= MPEG_VIDEO_BITRATE_MODE_MAX)
return -EINVAL;
if (params->video_target_bitrate >= MPEG_VIDEO_TARGET_BITRATE_MAX)
return -EINVAL;
- if (params->video_max_bitrate >= MPEG_VIDEO_MAX_BITRATE_MAX)
- return -EINVAL;
if (params->audio_bitrate >= MPEG_AUDIO_BITRATE_MAX)
return -EINVAL;
if (params->total_bitrate >= MPEG_TOTAL_BITRATE_MAX)
return -EINVAL;
- if (params->bitrate_mode == MPEG_BITRATE_MODE_MAX &&
- params->video_target_bitrate <= params->video_max_bitrate)
- return -EINVAL;
+ if (params->video_bitrate_mode == MPEG_VIDEO_BITRATE_MODE_VBR) {
+ if (params->video_max_bitrate >= MPEG_VIDEO_MAX_BITRATE_MAX)
+ return -EINVAL;
+ if (params->video_target_bitrate >= params->video_max_bitrate)
+ return -EINVAL;
+ }
+ if (params->pmt_pid != 0) {
+ if (params->pmt_pid > MPEG_PID_MAX)
+ return -EINVAL;
+ pmt_pid = params->pmt_pid;
+ } else {
+ pmt_pid = cachedParams->pmt_pid;
+ }
+ if (params->pcr_pid != 0) {
+ if (params->pcr_pid > MPEG_PID_MAX)
+ return -EINVAL;
+ pcr_pid = params->pcr_pid;
+ } else {
+ pcr_pid = cachedParams->pcr_pid;
+ }
+ if (params->video_pid != 0) {
+ if (params->video_pid > MPEG_PID_MAX)
+ return -EINVAL;
+ video_pid = params->video_pid;
+ } else {
+ video_pid = cachedParams->video_pid;
+ }
+ if (params->audio_pid != 0) {
+ if (params->audio_pid > MPEG_PID_MAX)
+ return -EINVAL;
+ audio_pid = params->audio_pid;
+ } else {
+ audio_pid = cachedParams->audio_pid;
+ }
+
+ // update cache
+ memcpy(cachedParams, params, sizeof(struct mpeg_params));
+ cachedParams->pmt_pid = pmt_pid;
+ cachedParams->pcr_pid = pcr_pid;
+ cachedParams->video_pid = video_pid;
+ cachedParams->audio_pid = audio_pid;
}
-
+
+ // set bitrate
+ saa6752hs_set_bitrate(client, cachedParams);
+
// Set GOP structure {3, 13}
buf[0] = 0x72;
buf[1] = 0x03;
@@ -283,27 +337,55 @@
buf[0] = 0xB0;
buf[1] = 0x05;
i2c_master_send(client,buf,2);
-
- // Set Audio PID {0x103}
+
+ /* compute PAT */
+ memcpy(localPAT, PAT, sizeof(PAT));
+ localPAT[17] = 0xe0 | ((cachedParams->pmt_pid >> 8) & 0x0f);
+ localPAT[18] = cachedParams->pmt_pid & 0xff;
+ crc = crc32_be(~0, &localPAT[7], sizeof(PAT) - 7 - 4);
+ localPAT[sizeof(PAT) - 4] = (crc >> 24) & 0xFF;
+ localPAT[sizeof(PAT) - 3] = (crc >> 16) & 0xFF;
+ localPAT[sizeof(PAT) - 2] = (crc >> 8) & 0xFF;
+ localPAT[sizeof(PAT) - 1] = crc & 0xFF;
+
+ /* compute PMT */
+ memcpy(localPMT, PMT, sizeof(PMT));
+ localPMT[3] = 0x40 | ((cachedParams->pmt_pid >> 8) & 0x0f);
+ localPMT[4] = cachedParams->pmt_pid & 0xff;
+ localPMT[15] = 0xE0 | ((cachedParams->pcr_pid >> 8) & 0x0F);
+ localPMT[16] = cachedParams->pcr_pid & 0xFF;
+ localPMT[20] = 0xE0 | ((cachedParams->video_pid >> 8) & 0x0F);
+ localPMT[21] = cachedParams->video_pid & 0xFF;
+ localPMT[25] = 0xE0 | ((cachedParams->audio_pid >> 8) & 0x0F);
+ localPMT[26] = cachedParams->audio_pid & 0xFF;
+ crc = crc32_be(~0, &localPMT[7], sizeof(PMT) - 7 - 4);
+ localPMT[sizeof(PMT) - 4] = (crc >> 24) & 0xFF;
+ localPMT[sizeof(PMT) - 3] = (crc >> 16) & 0xFF;
+ localPMT[sizeof(PMT) - 2] = (crc >> 8) & 0xFF;
+ localPMT[sizeof(PMT) - 1] = crc & 0xFF;
+
+ // Set Audio PID
buf[0] = 0xC1;
- buf[1] = 0x01;
- buf[2] = 0x03;
+ buf[1] = (cachedParams->audio_pid >> 8) & 0xFF;
+ buf[2] = cachedParams->audio_pid & 0xFF;
i2c_master_send(client,buf,3);
-
- // setup bitrate settings
- data = i2c_get_clientdata(client);
- if (params) {
- saa6752hs_set_bitrate(client, params);
- memcpy(data, params, sizeof(struct mpeg_params));
- } else {
- // parameters were not supplied. use the previous set
- saa6752hs_set_bitrate(client, (struct mpeg_params*) data);
- }
-
+
+ // Set Video PID
+ buf[0] = 0xC0;
+ buf[1] = (cachedParams->video_pid >> 8) & 0xFF;
+ buf[2] = cachedParams->video_pid & 0xFF;
+ i2c_master_send(client,buf,3);
+
+ // Set PCR PID
+ buf[0] = 0xC4;
+ buf[1] = (cachedParams->pcr_pid >> 8) & 0xFF;
+ buf[2] = cachedParams->pcr_pid & 0xFF;
+ i2c_master_send(client,buf,3);
+
// Send SI tables
- i2c_master_send(client,PAT,sizeof(PAT));
- i2c_master_send(client,PMT,sizeof(PMT));
-
+ i2c_master_send(client,localPAT,sizeof(PAT));
+ i2c_master_send(client,localPMT,sizeof(PMT));
+
// mute then unmute audio. This removes buzzing artefacts
buf[0] = 0xa4;
buf[1] = 1;
@@ -384,10 +466,14 @@
saa6752hs_command(struct i2c_client *client, unsigned int cmd, void *arg)
{
struct mpeg_params* init_arg = arg;
+ int result;
switch (cmd) {
case MPEG_SETPARAMS:
- return saa6752hs_init(client, init_arg);
+ result = saa6752hs_init(client, init_arg);
+ if (result != 0)
+ printk("saa6752hs: MPEG_SETPARAMS failed: %i\n", result);
+ return result;
default:
/* nothing */
diff -Nau saa7134-0.2.12.orig/saa6752hs.h saa7134-0.2.12/saa6752hs.h
--- saa7134-0.2.12.orig/saa6752hs.h 2004-02-22 01:59:35.000000000 +0000
+++ saa7134-0.2.12/saa6752hs.h 2004-05-17 11:47:13.000000000 +0100
@@ -21,11 +21,11 @@
#ifndef _SAA6752HS_H
#define _SAA6752HS_H
-enum mpeg_bitrate_mode {
- MPEG_BITRATE_MODE_VBR = 0, /* Variable bitrate */
- MPEG_BITRATE_MODE_CBR = 1, /* Constant bitrate */
+enum mpeg_video_bitrate_mode {
+ MPEG_VIDEO_BITRATE_MODE_VBR = 0, /* Variable bitrate */
+ MPEG_VIDEO_BITRATE_MODE_CBR = 1, /* Constant bitrate */
- MPEG_BITRATE_MODE_MAX
+ MPEG_VIDEO_BITRATE_MODE_MAX
};
enum mpeg_audio_bitrate {
@@ -38,13 +38,19 @@
#define MPEG_VIDEO_TARGET_BITRATE_MAX 27000
#define MPEG_VIDEO_MAX_BITRATE_MAX 27000
#define MPEG_TOTAL_BITRATE_MAX 27000
-
+#define MPEG_PID_MAX ((1 << 14) - 1)
+
struct mpeg_params {
- enum mpeg_bitrate_mode bitrate_mode;
+ enum mpeg_video_bitrate_mode video_bitrate_mode;
unsigned int video_target_bitrate;
unsigned int video_max_bitrate; // only used for VBR
enum mpeg_audio_bitrate audio_bitrate;
unsigned int total_bitrate;
+
+ unsigned int pmt_pid;
+ unsigned int video_pid;
+ unsigned int audio_pid;
+ unsigned int pcr_pid;
};
#define MPEG_SETPARAMS _IOW('6',100,struct mpeg_params)
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