libsigrok/input/chronovu_la8.c

207 lines
5.6 KiB
C

/*
* This file is part of the libsigrok project.
*
* Copyright (C) 2011 Uwe Hermann <uwe@hermann-uwe.de>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <stdlib.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/stat.h>
#include "libsigrok.h"
#include "libsigrok-internal.h"
#define LOG_PREFIX "input/chronovu-la8"
#define NUM_PACKETS 2048
#define PACKET_SIZE 4096
#define DEFAULT_NUM_CHANNELS 8
/**
* Convert the LA8 'divcount' value to the respective samplerate (in Hz).
*
* LA8 hardware: sample period = (divcount + 1) * 10ns.
* Min. value for divcount: 0x00 (10ns sample period, 100MHz samplerate).
* Max. value for divcount: 0xfe (2550ns sample period, 392.15kHz samplerate).
*
* @param divcount The divcount value as needed by the hardware.
*
* @return The samplerate in Hz, or 0xffffffffffffffff upon errors.
*/
static uint64_t divcount_to_samplerate(uint8_t divcount)
{
if (divcount == 0xff)
return 0xffffffffffffffffULL;
return SR_MHZ(100) / (divcount + 1);
}
static int format_match(const char *filename)
{
struct stat stat_buf;
int ret;
if (!filename) {
sr_err("%s: filename was NULL", __func__);
// return SR_ERR; /* FIXME */
return FALSE;
}
if (!g_file_test(filename, G_FILE_TEST_EXISTS)) {
sr_err("%s: input file '%s' does not exist",
__func__, filename);
// return SR_ERR; /* FIXME */
return FALSE;
}
if (!g_file_test(filename, G_FILE_TEST_IS_REGULAR)) {
sr_err("%s: input file '%s' not a regular file",
__func__, filename);
// return SR_ERR; /* FIXME */
return FALSE;
}
/* Only accept files of length 8MB + 5 bytes. */
ret = stat(filename, &stat_buf);
if (ret != 0) {
sr_err("%s: Error getting file size of '%s'",
__func__, filename);
return FALSE;
}
if (stat_buf.st_size != (8 * 1024 * 1024 + 5)) {
sr_dbg("%s: File size must be exactly 8388613 bytes ("
"it actually is %d bytes in size), so this is not a "
"ChronoVu LA8 file.", __func__, stat_buf.st_size);
return FALSE;
}
/* TODO: Check for divcount != 0xff. */
return TRUE;
}
static int init(struct sr_input *in, const char *filename)
{
struct sr_channel *ch;
int num_channels, i;
char name[SR_MAX_CHANNELNAME_LEN + 1];
char *param;
(void)filename;
num_channels = DEFAULT_NUM_CHANNELS;
if (in->param) {
param = g_hash_table_lookup(in->param, "numchannels");
if (param) {
num_channels = strtoul(param, NULL, 10);
if (num_channels < 1) {
sr_err("%s: strtoul failed", __func__);
return SR_ERR;
}
}
}
/* Create a virtual device. */
in->sdi = sr_dev_inst_new(0, SR_ST_ACTIVE, NULL, NULL, NULL);
for (i = 0; i < num_channels; i++) {
snprintf(name, SR_MAX_CHANNELNAME_LEN, "%d", i);
/* TODO: Check return value. */
if (!(ch = sr_channel_new(i, SR_CHANNEL_LOGIC, TRUE, name)))
return SR_ERR;
in->sdi->channels = g_slist_append(in->sdi->channels, ch);
}
return SR_OK;
}
static int loadfile(struct sr_input *in, const char *filename)
{
struct sr_datafeed_packet packet;
struct sr_datafeed_meta meta;
struct sr_datafeed_logic logic;
struct sr_config *src;
uint8_t buf[PACKET_SIZE], divcount;
int i, fd, size, num_channels;
uint64_t samplerate;
/* TODO: Use glib functions! GIOChannel, g_fopen, etc. */
if ((fd = open(filename, O_RDONLY)) == -1) {
sr_err("%s: file open failed", __func__);
return SR_ERR;
}
num_channels = g_slist_length(in->sdi->channels);
/* Seek to the end of the file, and read the divcount byte. */
divcount = 0x00; /* TODO: Don't hardcode! */
/* Convert the divcount value to a samplerate. */
samplerate = divcount_to_samplerate(divcount);
if (samplerate == 0xffffffffffffffffULL) {
close(fd); /* FIXME */
return SR_ERR;
}
sr_dbg("%s: samplerate is %" PRIu64, __func__, samplerate);
/* Send header packet to the session bus. */
std_session_send_df_header(in->sdi, LOG_PREFIX);
/* Send metadata about the SR_DF_LOGIC packets to come. */
packet.type = SR_DF_META;
packet.payload = &meta;
src = sr_config_new(SR_CONF_SAMPLERATE, g_variant_new_uint64(samplerate));
meta.config = g_slist_append(NULL, src);
sr_session_send(in->sdi, &packet);
sr_config_free(src);
/* TODO: Handle trigger point. */
/* Send data packets to the session bus. */
sr_dbg("%s: sending SR_DF_LOGIC data packets", __func__);
packet.type = SR_DF_LOGIC;
packet.payload = &logic;
logic.unitsize = (num_channels + 7) / 8;
logic.data = buf;
/* Send 8MB of total data to the session bus in small chunks. */
for (i = 0; i < NUM_PACKETS; i++) {
/* TODO: Handle errors, handle incomplete reads. */
size = read(fd, buf, PACKET_SIZE);
logic.length = size;
sr_session_send(in->sdi, &packet);
}
close(fd); /* FIXME */
/* Send end packet to the session bus. */
sr_dbg("%s: sending SR_DF_END", __func__);
packet.type = SR_DF_END;
packet.payload = NULL;
sr_session_send(in->sdi, &packet);
return SR_OK;
}
SR_PRIV struct sr_input_format input_chronovu_la8 = {
.id = "chronovu-la8",
.description = "ChronoVu LA8",
.format_match = format_match,
.init = init,
.loadfile = loadfile,
};