libsigrok/hardware/chronovu-la8/protocol.c

538 lines
15 KiB
C

/*
* This file is part of the sigrok project.
*
* Copyright (C) 2011-2012 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 <ftdi.h>
#include <glib.h>
#include "libsigrok.h"
#include "libsigrok-internal.h"
#include "protocol.h"
/* Probes are numbered 0-7. */
SR_PRIV const char *probe_names[NUM_PROBES + 1] = {
"0", "1", "2", "3", "4", "5", "6", "7",
NULL,
};
/* This will be initialized via config_list()/SR_CONF_SAMPLERATE. */
SR_PRIV uint64_t supported_samplerates[255 + 1] = { 0 };
/*
* Min: 1 sample per 0.01us -> sample time is 0.084s, samplerate 100MHz
* Max: 1 sample per 2.55us -> sample time is 21.391s, samplerate 392.15kHz
*/
const struct sr_samplerates samplerates = {
.low = 0,
.high = 0,
.step = 0,
.list = supported_samplerates,
};
/* Note: Continuous sampling is not supported by the hardware. */
SR_PRIV const int hwcaps[] = {
SR_CONF_LOGIC_ANALYZER,
SR_CONF_SAMPLERATE,
SR_CONF_LIMIT_MSEC, /* TODO: Not yet implemented. */
SR_CONF_LIMIT_SAMPLES, /* TODO: Not yet implemented. */
0,
};
SR_PRIV void fill_supported_samplerates_if_needed(void)
{
int i;
/* Do nothing if supported_samplerates[] is already filled. */
if (supported_samplerates[0] != 0)
return;
/* Fill supported_samplerates[] with the proper values. */
for (i = 0; i < 255; i++)
supported_samplerates[254 - i] = SR_MHZ(100) / (i + 1);
supported_samplerates[255] = 0;
}
/**
* Check if the given samplerate is supported by the LA8 hardware.
*
* @param samplerate The samplerate (in Hz) to check.
* @return 1 if the samplerate is supported/valid, 0 otherwise.
*/
SR_PRIV int is_valid_samplerate(uint64_t samplerate)
{
int i;
fill_supported_samplerates_if_needed();
for (i = 0; i < 255; i++) {
if (supported_samplerates[i] == samplerate)
return 1;
}
sr_err("Invalid samplerate (%" PRIu64 "Hz).", samplerate);
return 0;
}
/**
* Convert a samplerate (in Hz) to the 'divcount' value the LA8 wants.
*
* 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 samplerate The samplerate in Hz.
* @return The divcount value as needed by the hardware, or 0xff upon errors.
*/
SR_PRIV uint8_t samplerate_to_divcount(uint64_t samplerate)
{
if (samplerate == 0) {
sr_err("%s: samplerate was 0.", __func__);
return 0xff;
}
if (!is_valid_samplerate(samplerate)) {
sr_err("%s: Can't get divcount, samplerate invalid.", __func__);
return 0xff;
}
return (SR_MHZ(100) / samplerate) - 1;
}
/**
* Write data of a certain length to the LA8's FTDI device.
*
* @param devc The struct containing private per-device-instance data. Must not
* be NULL. devc->ftdic must not be NULL either.
* @param buf The buffer containing the data to write. Must not be NULL.
* @param size The number of bytes to write. Must be >= 0.
* @return The number of bytes written, or a negative value upon errors.
*/
SR_PRIV int la8_write(struct dev_context *devc, uint8_t *buf, int size)
{
int bytes_written;
/* Note: Caller checked that devc and devc->ftdic != NULL. */
if (!buf) {
sr_err("%s: buf was NULL.", __func__);
return SR_ERR_ARG;
}
if (size < 0) {
sr_err("%s: size was < 0.", __func__);
return SR_ERR_ARG;
}
bytes_written = ftdi_write_data(devc->ftdic, buf, size);
if (bytes_written < 0) {
sr_err("%s: ftdi_write_data: (%d) %s.", __func__,
bytes_written, ftdi_get_error_string(devc->ftdic));
(void) la8_close_usb_reset_sequencer(devc); /* Ignore errors. */
} else if (bytes_written != size) {
sr_err("%s: bytes to write: %d, bytes written: %d.",
__func__, size, bytes_written);
(void) la8_close_usb_reset_sequencer(devc); /* Ignore errors. */
}
return bytes_written;
}
/**
* Read a certain amount of bytes from the LA8's FTDI device.
*
* @param devc The struct containing private per-device-instance data. Must not
* be NULL. devc->ftdic must not be NULL either.
* @param buf The buffer where the received data will be stored. Must not
* be NULL.
* @param size The number of bytes to read. Must be >= 1.
* @return The number of bytes read, or a negative value upon errors.
*/
SR_PRIV int la8_read(struct dev_context *devc, uint8_t *buf, int size)
{
int bytes_read;
/* Note: Caller checked that devc and devc->ftdic != NULL. */
if (!buf) {
sr_err("%s: buf was NULL.", __func__);
return SR_ERR_ARG;
}
if (size <= 0) {
sr_err("%s: size was <= 0.", __func__);
return SR_ERR_ARG;
}
bytes_read = ftdi_read_data(devc->ftdic, buf, size);
if (bytes_read < 0) {
sr_err("%s: ftdi_read_data: (%d) %s.", __func__,
bytes_read, ftdi_get_error_string(devc->ftdic));
} else if (bytes_read != size) {
// sr_err("%s: Bytes to read: %d, bytes read: %d.",
// __func__, size, bytes_read);
}
return bytes_read;
}
SR_PRIV int la8_close(struct dev_context *devc)
{
int ret;
if (!devc) {
sr_err("%s: devc was NULL.", __func__);
return SR_ERR_ARG;
}
if (!devc->ftdic) {
sr_err("%s: devc->ftdic was NULL.", __func__);
return SR_ERR_ARG;
}
if ((ret = ftdi_usb_close(devc->ftdic)) < 0) {
sr_err("%s: ftdi_usb_close: (%d) %s.",
__func__, ret, ftdi_get_error_string(devc->ftdic));
}
return ret;
}
/**
* Close the ChronoVu LA8 USB port and reset the LA8 sequencer logic.
*
* @param devc The struct containing private per-device-instance data.
* @return SR_OK upon success, SR_ERR_ARG upon invalid arguments.
*/
SR_PRIV int la8_close_usb_reset_sequencer(struct dev_context *devc)
{
/* Magic sequence of bytes for resetting the LA8 sequencer logic. */
uint8_t buf[8] = {0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01};
int ret;
if (!devc) {
sr_err("%s: devc was NULL.", __func__);
return SR_ERR_ARG;
}
if (!devc->ftdic) {
sr_err("%s: devc->ftdic was NULL.", __func__);
return SR_ERR_ARG;
}
if (devc->ftdic->usb_dev) {
/* Reset the LA8 sequencer logic, then wait 100ms. */
sr_dbg("Resetting sequencer logic.");
(void) la8_write(devc, buf, 8); /* Ignore errors. */
g_usleep(100 * 1000);
/* Purge FTDI buffers, then reset and close the FTDI device. */
sr_dbg("Purging buffers, resetting+closing FTDI device.");
/* Log errors, but ignore them (i.e., don't abort). */
if ((ret = ftdi_usb_purge_buffers(devc->ftdic)) < 0)
sr_err("%s: ftdi_usb_purge_buffers: (%d) %s.",
__func__, ret, ftdi_get_error_string(devc->ftdic));
if ((ret = ftdi_usb_reset(devc->ftdic)) < 0)
sr_err("%s: ftdi_usb_reset: (%d) %s.", __func__,
ret, ftdi_get_error_string(devc->ftdic));
if ((ret = ftdi_usb_close(devc->ftdic)) < 0)
sr_err("%s: ftdi_usb_close: (%d) %s.", __func__,
ret, ftdi_get_error_string(devc->ftdic));
}
/* Close USB device, deinitialize and free the FTDI context. */
ftdi_free(devc->ftdic); /* Returns void. */
devc->ftdic = NULL;
return SR_OK;
}
/**
* Reset the ChronoVu LA8.
*
* The LA8 must be reset after a failed read/write operation or upon timeouts.
*
* @param devc The struct containing private per-device-instance data.
* @return SR_OK upon success, SR_ERR upon failure.
*/
SR_PRIV int la8_reset(struct dev_context *devc)
{
uint8_t buf[BS];
time_t done, now;
int bytes_read;
if (!devc) {
sr_err("%s: devc was NULL.", __func__);
return SR_ERR_ARG;
}
if (!devc->ftdic) {
sr_err("%s: devc->ftdic was NULL.", __func__);
return SR_ERR_ARG;
}
sr_dbg("Resetting the device.");
/*
* Purge pending read data from the FTDI hardware FIFO until
* no more data is left, or a timeout occurs (after 20s).
*/
done = 20 + time(NULL);
do {
/* TODO: Ignore errors? Check for < 0 at least! */
bytes_read = la8_read(devc, (uint8_t *)&buf, BS);
now = time(NULL);
} while ((done > now) && (bytes_read > 0));
/* Reset the LA8 sequencer logic and close the USB port. */
(void) la8_close_usb_reset_sequencer(devc); /* Ignore errors. */
sr_dbg("Device reset finished.");
return SR_OK;
}
SR_PRIV int configure_probes(const struct sr_dev_inst *sdi)
{
struct dev_context *devc;
const struct sr_probe *probe;
const GSList *l;
uint8_t probe_bit;
char *tc;
devc = sdi->priv;
devc->trigger_pattern = 0;
devc->trigger_mask = 0; /* Default to "don't care" for all probes. */
for (l = sdi->probes; l; l = l->next) {
probe = (struct sr_probe *)l->data;
if (!probe) {
sr_err("%s: probe was NULL.", __func__);
return SR_ERR;
}
/* Skip disabled probes. */
if (!probe->enabled)
continue;
/* Skip (enabled) probes with no configured trigger. */
if (!probe->trigger)
continue;
/* Note: Must only be run if probe->trigger != NULL. */
if (probe->index < 0 || probe->index > 7) {
sr_err("%s: Invalid probe index %d, must be "
"between 0 and 7.", __func__, probe->index);
return SR_ERR;
}
probe_bit = (1 << (probe->index));
/* Configure the probe's trigger mask and trigger pattern. */
for (tc = probe->trigger; tc && *tc; tc++) {
devc->trigger_mask |= probe_bit;
/* Sanity check, LA8 only supports low/high trigger. */
if (*tc != '0' && *tc != '1') {
sr_err("%s: Invalid trigger '%c', only "
"'0'/'1' supported.", __func__, *tc);
return SR_ERR;
}
if (*tc == '1')
devc->trigger_pattern |= probe_bit;
}
}
sr_dbg("Trigger mask = 0x%x, trigger pattern = 0x%x.",
devc->trigger_mask, devc->trigger_pattern);
return SR_OK;
}
SR_PRIV int set_samplerate(const struct sr_dev_inst *sdi, uint64_t samplerate)
{
struct dev_context *devc;
/* Note: Caller checked that sdi and sdi->priv != NULL. */
devc = sdi->priv;
sr_spew("Trying to set samplerate to %" PRIu64 "Hz.", samplerate);
fill_supported_samplerates_if_needed();
/* Check if this is a samplerate supported by the hardware. */
if (!is_valid_samplerate(samplerate))
return SR_ERR;
/* Set the new samplerate. */
devc->cur_samplerate = samplerate;
sr_dbg("Samplerate set to %" PRIu64 "Hz.", devc->cur_samplerate);
return SR_OK;
}
/**
* Get a block of data from the LA8.
*
* @param devc The struct containing private per-device-instance data. Must not
* be NULL. devc->ftdic must not be NULL either.
* @return SR_OK upon success, or SR_ERR upon errors.
*/
SR_PRIV int la8_read_block(struct dev_context *devc)
{
int i, byte_offset, m, mi, p, index, bytes_read;
time_t now;
/* Note: Caller checked that devc and devc->ftdic != NULL. */
sr_spew("Reading block %d.", devc->block_counter);
bytes_read = la8_read(devc, devc->mangled_buf, BS);
/* If first block read got 0 bytes, retry until success or timeout. */
if ((bytes_read == 0) && (devc->block_counter == 0)) {
do {
sr_spew("Reading block 0 (again).");
bytes_read = la8_read(devc, devc->mangled_buf, BS);
/* TODO: How to handle read errors here? */
now = time(NULL);
} while ((devc->done > now) && (bytes_read == 0));
}
/* Check if block read was successful or a timeout occured. */
if (bytes_read != BS) {
sr_err("Trigger timed out. Bytes read: %d.", bytes_read);
(void) la8_reset(devc); /* Ignore errors. */
return SR_ERR;
}
/* De-mangle the data. */
sr_spew("Demangling block %d.", devc->block_counter);
byte_offset = devc->block_counter * BS;
m = byte_offset / (1024 * 1024);
mi = m * (1024 * 1024);
for (i = 0; i < BS; i++) {
p = i & (1 << 0);
index = m * 2 + (((byte_offset + i) - mi) / 2) * 16;
index += (devc->divcount == 0) ? p : (1 - p);
devc->final_buf[index] = devc->mangled_buf[i];
}
return SR_OK;
}
SR_PRIV void send_block_to_session_bus(struct dev_context *devc, int block)
{
int i;
uint8_t sample, expected_sample;
struct sr_datafeed_packet packet;
struct sr_datafeed_logic logic;
int trigger_point; /* Relative trigger point (in this block). */
/* Note: No sanity checks on devc/block, caller is responsible. */
/* Check if we can find the trigger condition in this block. */
trigger_point = -1;
expected_sample = devc->trigger_pattern & devc->trigger_mask;
for (i = 0; i < BS; i++) {
/* Don't continue if the trigger was found previously. */
if (devc->trigger_found)
break;
/*
* Also, don't continue if triggers are "don't care", i.e. if
* no trigger conditions were specified by the user. In that
* case we don't want to send an SR_DF_TRIGGER packet at all.
*/
if (devc->trigger_mask == 0x00)
break;
sample = *(devc->final_buf + (block * BS) + i);
if ((sample & devc->trigger_mask) == expected_sample) {
trigger_point = i;
devc->trigger_found = 1;
break;
}
}
/* If no trigger was found, send one SR_DF_LOGIC packet. */
if (trigger_point == -1) {
/* Send an SR_DF_LOGIC packet to the session bus. */
sr_spew("Sending SR_DF_LOGIC packet (%d bytes) for "
"block %d.", BS, block);
packet.type = SR_DF_LOGIC;
packet.payload = &logic;
logic.length = BS;
logic.unitsize = 1;
logic.data = devc->final_buf + (block * BS);
sr_session_send(devc->cb_data, &packet);
return;
}
/*
* We found the trigger, so some special handling is needed. We have
* to send an SR_DF_LOGIC packet with the samples before the trigger
* (if any), then the SD_DF_TRIGGER packet itself, then another
* SR_DF_LOGIC packet with the samples after the trigger (if any).
*/
/* TODO: Send SR_DF_TRIGGER packet before or after the actual sample? */
/* If at least one sample is located before the trigger... */
if (trigger_point > 0) {
/* Send pre-trigger SR_DF_LOGIC packet to the session bus. */
sr_spew("Sending pre-trigger SR_DF_LOGIC packet, "
"start = %d, length = %d.", block * BS, trigger_point);
packet.type = SR_DF_LOGIC;
packet.payload = &logic;
logic.length = trigger_point;
logic.unitsize = 1;
logic.data = devc->final_buf + (block * BS);
sr_session_send(devc->cb_data, &packet);
}
/* Send the SR_DF_TRIGGER packet to the session bus. */
sr_spew("Sending SR_DF_TRIGGER packet, sample = %d.",
(block * BS) + trigger_point);
packet.type = SR_DF_TRIGGER;
packet.payload = NULL;
sr_session_send(devc->cb_data, &packet);
/* If at least one sample is located after the trigger... */
if (trigger_point < (BS - 1)) {
/* Send post-trigger SR_DF_LOGIC packet to the session bus. */
sr_spew("Sending post-trigger SR_DF_LOGIC packet, "
"start = %d, length = %d.",
(block * BS) + trigger_point, BS - trigger_point);
packet.type = SR_DF_LOGIC;
packet.payload = &logic;
logic.length = BS - trigger_point;
logic.unitsize = 1;
logic.data = devc->final_buf + (block * BS) + trigger_point;
sr_session_send(devc->cb_data, &packet);
}
}