libsigrok/device.c

490 lines
14 KiB
C

/*
* This file is part of the sigrok project.
*
* Copyright (C) 2010 Bert Vermeulen <bert@biot.com>
*
* 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 3 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, see <http://www.gnu.org/licenses/>.
*/
#include <stdio.h>
#include <glib.h>
#include "sigrok.h"
#include "sigrok-internal.h"
static GSList *devices = NULL;
/**
* Scan the system for attached logic analyzers / devices.
*
* This will try to autodetect all supported logic analyzer devices:
*
* - Those attached via USB (can be reliably detected via USB VID/PID).
*
* - Those using a (real or virtual) serial port (detected by sending
* device-specific commands to all OS-specific serial port devices such
* as /dev/ttyS*, /dev/ttyUSB*, /dev/ttyACM*, and others).
* The autodetection for this kind of devices can potentially be unreliable.
*
* Also, sending various bytes/commands to (all!) devices which happen to
* be attached to the system via a (real or virtual) serial port can be
* problematic. There is no way for libsigrok to know how unknown devices
* react to the bytes libsigrok sends. Potentially they could lead to the
* device getting into invalid/error states, losing/overwriting data, or...
*
* In addition to the detection, the devices that are found are also
* initialized automatically. On some devices, this involves a firmware upload,
* or other such measures.
*
* The order in which the system is scanned for devices is not specified. The
* caller should not assume or rely on any specific order.
*
* After the system has been scanned for devices, the list of detected (and
* supported) devices can be acquired via sr_device_list().
*
* TODO: Error checks?
* TODO: Option to only scan for specific devices or device classes.
*
* @return SR_OK upon success, SR_ERR upon errors.
*/
int sr_device_scan(void)
{
GSList *plugins, *l;
struct sr_device_plugin *plugin;
if (!(plugins = sr_list_hwplugins())) {
sr_err("dev: %s: no supported devices/hwplugins", __func__);
return SR_ERR; /* TODO: More specific error? */
}
/*
* Initialize all plugins first. Since the init() call may involve
* a firmware upload and associated delay, we may as well get all
* of these out of the way first.
*/
for (l = plugins; l; l = l->next) {
plugin = l->data;
/* TODO: Handle 'plugin' being NULL. */
sr_init_hwplugins(plugin);
}
return SR_OK;
}
/**
* Return the list of logic analyzer devices libsigrok has detected.
*
* If the libsigrok-internal device list is empty, a scan for attached
* devices -- via a call to sr_device_scan() -- is performed first.
*
* TODO: Error handling?
*
* @return The list (GSList) of detected devices, or NULL if none were found.
*/
GSList *sr_device_list(void)
{
if (!devices)
sr_device_scan();
return devices;
}
/**
* Create a new device.
*
* The device is added to the (libsigrok-internal) list of devices, but
* additionally a pointer to the newly created device is also returned.
*
* The device has no probes attached to it yet after this call. You can
* use sr_device_probe_add() to add one or more probes.
*
* TODO: Should return int, so that we can return SR_OK, SR_ERR_* etc.
*
* It is the caller's responsibility to g_free() the allocated memory when
* no longer needed. TODO: Using which API function?
*
* @param plugin TODO.
* If 'plugin' is NULL, the created device is a "virtual" one.
* @param plugin_index TODO
*
* @return Pointer to the newly allocated device, or NULL upon errors.
*/
struct sr_device *sr_device_new(const struct sr_device_plugin *plugin,
int plugin_index)
{
struct sr_device *device;
/* TODO: Check if plugin_index valid? */
if (!(device = g_try_malloc0(sizeof(struct sr_device)))) {
sr_err("dev: %s: device malloc failed", __func__);
return NULL;
}
device->plugin = (struct sr_device_plugin *)plugin;
device->plugin_index = plugin_index;
devices = g_slist_append(devices, device);
return device;
}
/**
* Clear all probes of the specified device.
*
* This removes/clears the 'name' and 'trigger' fields of all probes of
* the device.
*
* The order in which the probes are cleared is not specified. The caller
* should not assume or rely on a specific order.
*
* TODO: Rename to sr_device_clear_probes() or sr_device_probe_clear_all().
*
* @param device The device whose probes to clear. Must not be NULL.
* Note: device->probes is allowed to be NULL (in that case,
* there are no probes, thus none have to be cleared).
*
* @return SR_OK upon success, SR_ERR_ARG upon invalid arguments.
* If something other than SR_OK is returned, 'device' is unchanged.
*/
int sr_device_clear(struct sr_device *device)
{
unsigned int pnum;
if (!device) {
sr_err("dev: %s: device was NULL", __func__);
return SR_ERR_ARG;
}
/* Note: device->probes can be NULL, this is handled correctly. */
for (pnum = 1; pnum <= g_slist_length(device->probes); pnum++)
sr_device_probe_clear(device, pnum);
return SR_OK;
}
/**
* Clear the specified probe in the specified device.
*
* The probe itself still exists afterwards, but its 'name' and 'trigger'
* fields are g_free()'d and set to NULL.
*
* @param device The device in which the specified (to be cleared) probe
* resides. Must not be NULL.
* @param probenum The number of the probe to clear.
* Note that the probe numbers start at 1 (not 0!).
*
* @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or SR_ERR
* upon other errors.
* If something other than SR_OK is returned, 'device' is unchanged.
*/
int sr_device_probe_clear(struct sr_device *device, int probenum)
{
struct sr_probe *p;
if (!device) {
sr_err("dev: %s: device was NULL", __func__);
return SR_ERR_ARG;
}
/* TODO: Sanity check on 'probenum'. */
if (!(p = sr_device_probe_find(device, probenum))) {
sr_err("dev: %s: probe %d not found", __func__, probenum);
return SR_ERR; /* TODO: More specific error? */
}
/* If the probe has a name, remove it. */
if (p->name) {
g_free(p->name);
p->name = NULL;
}
/* If the probe has a trigger, remove it. */
if (p->trigger) {
g_free(p->trigger);
p->trigger = NULL;
}
return SR_OK;
}
/**
* Add a probe with the specified name to the specified device.
*
* The added probe is automatically enabled (the 'enabled' field is TRUE).
*
* The 'trigger' field of the added probe is set to NULL. A trigger can be
* added via sr_device_trigger_set().
*
* TODO: Are duplicate names allowed?
* TODO: Do we enforce a maximum probe number for a device?
* TODO: Error if the max. probe number for the specific LA is reached, e.g.
* if the caller tries to add more probes than the device actually has.
*
* @param device The device to which to add a probe with the specified name.
* Must not be NULL.
* @param name The name of the probe to add to this device. Must not be NULL.
* TODO: Maximum length, allowed characters, etc.
*
* @return SR_OK upon success, SR_ERR_MALLOC upon memory allocation errors,
* or SR_ERR_ARG upon invalid arguments.
* If something other than SR_OK is returned, 'device' is unchanged.
*/
int sr_device_probe_add(struct sr_device *device, const char *name)
{
struct sr_probe *p;
int probenum;
if (!device) {
sr_err("dev: %s: device was NULL", __func__);
return SR_ERR_ARG;
}
if (!name) {
sr_err("dev: %s: name was NULL", __func__);
return SR_ERR_ARG;
}
/* TODO: Further checks to ensure name is valid. */
probenum = g_slist_length(device->probes) + 1;
if (!(p = g_try_malloc0(sizeof(struct sr_probe)))) {
sr_err("dev: %s: p malloc failed", __func__);
return SR_ERR_MALLOC;
}
p->index = probenum;
p->enabled = TRUE;
p->name = g_strdup(name);
p->trigger = NULL;
device->probes = g_slist_append(device->probes, p);
return SR_OK;
}
/**
* Find the probe with the specified number in the specified device.
*
* TODO
*
* @param device TODO. Must not be NULL.
* @param probenum The number of the probe whose 'struct sr_probe' we want.
* Note that the probe numbers start at 1 (not 0!).
*
* TODO: Should return int.
* TODO: probenum should be unsigned.
*
* @return A pointer to the requested probe's 'struct sr_probe', or NULL
* if the probe could not be found.
*/
struct sr_probe *sr_device_probe_find(const struct sr_device *device,
int probenum)
{
GSList *l;
struct sr_probe *p, *found_probe;
if (!device) {
sr_err("dev: %s: device was NULL", __func__);
return NULL; /* TODO: SR_ERR_ARG */
}
/* TODO: Sanity check on probenum. */
found_probe = NULL;
for (l = device->probes; l; l = l->next) {
p = l->data;
/* TODO: Check for p != NULL. */
if (p->index == probenum) {
found_probe = p;
break;
}
}
return found_probe;
}
/**
* Set the name of the specified probe in the specified device.
*
* If the probe already has a different name assigned to it, it will be
* removed, and the new name will be saved instead.
*
* TODO: Rename to sr_device_set_probe_name().
*
* @param device TODO
* @param probenum The number of the probe whose name to set.
* Note that the probe numbers start at 1 (not 0!).
* @param name The new name that the specified probe should get.
*
* @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or SR_ERR
* upon other errors.
* If something other than SR_OK is returned, 'device' is unchanged.
*/
int sr_device_probe_name(struct sr_device *device, int probenum,
const char *name)
{
struct sr_probe *p;
if (!device) {
sr_err("dev: %s: device was NULL", __func__);
return SR_ERR_ARG;
}
p = sr_device_probe_find(device, probenum);
if (!p) {
sr_err("dev: %s: probe %d not found", __func__, probenum);
return SR_ERR; /* TODO: More specific error? */
}
/* TODO: Sanity check on 'name'. */
/* If the probe already has a name, kill it first. */
if (p->name)
g_free(p->name);
p->name = g_strdup(name);
return SR_OK;
}
/**
* Remove all triggers set up for the specified device.
*
* TODO: Better description.
*
* @param device TODO
*
* @return SR_OK upon success, SR_ERR_ARG upon invalid arguments.
* If something other than SR_OK is returned, 'device' is unchanged.
*/
int sr_device_trigger_clear(struct sr_device *device)
{
struct sr_probe *p;
unsigned int pnum; /* TODO: uint16_t? */
if (!device) {
sr_err("dev: %s: device was NULL", __func__);
return SR_ERR_ARG;
}
if (!device->probes) {
sr_err("dev: %s: device->probes was NULL", __func__);
return SR_ERR_ARG;
}
for (pnum = 1; pnum <= g_slist_length(device->probes); pnum++) {
p = sr_device_probe_find(device, pnum);
/* TODO: Silently ignore probes which cannot be found? */
if (p && p->trigger) {
g_free(p->trigger);
p->trigger = NULL;
}
}
return SR_OK;
}
/**
* Add a trigger to the specified device.
*
* TODO: Better description.
* TODO: Describe valid format of the 'trigger' string.
*
* @param device TODO. Must not be NULL.
* @param probenum The number of the probe. TODO.
* Note that the probe numbers start at 1 (not 0!).
* @param trigger TODO.
* TODO: Is NULL allowed?
*
* @return SR_OK upon success, SR_ERR_ARG upon invalid arguments, or SR_ERR
* upon other errors.
* If something other than SR_OK is returned, 'device' is unchanged.
*/
int sr_device_trigger_set(struct sr_device *device, int probenum,
const char *trigger)
{
struct sr_probe *p;
if (!device) {
sr_err("dev: %s: device was NULL", __func__);
return SR_ERR_ARG;
}
/* TODO: Sanity check on 'probenum'. */
/* TODO: Sanity check on 'trigger'. */
p = sr_device_probe_find(device, probenum);
if (!p) {
sr_err("dev: %s: probe %d not found", __func__, probenum);
return SR_ERR; /* TODO: More specific error? */
}
/* If the probe already has a trigger, kill it first. */
if (p->trigger)
g_free(p->trigger);
p->trigger = g_strdup(trigger);
return SR_OK;
}
/**
* Determine whether the specified device has the specified capability.
*
* TODO: Should return int?
*
* @param device Pointer to the device to be checked. Must not be NULL.
* The device's 'plugin' field must not be NULL either.
* @param hwcap The capability that should be checked (whether it's supported
* by the specified device).
*
* @return TRUE, if the device has the specified capability, FALSE otherwise.
* FALSE is also returned upon invalid input parameters or other
* error conditions.
*/
gboolean sr_device_has_hwcap(const struct sr_device *device, int hwcap)
{
int *capabilities, i;
if (!device) {
sr_err("dev: %s: device was NULL", __func__);
return FALSE; /* TODO: SR_ERR_ARG. */
}
if (!device->plugin) {
sr_err("dev: %s: device->plugin was NULL", __func__);
return FALSE; /* TODO: SR_ERR_ARG. */
}
/* TODO: Sanity check on 'hwcap'. */
if (!(capabilities = device->plugin->get_capabilities())) {
sr_err("dev: %s: device has no capabilities", __func__);
return FALSE; /* TODO: SR_ERR*. */
}
for (i = 0; capabilities[i]; i++) {
if (capabilities[i] != hwcap)
continue;
sr_spew("dev: %s: found hwcap %d", __func__, hwcap);
return TRUE;
}
sr_spew("dev: %s: hwcap %d not found", __func__, hwcap);
return FALSE;
}