libsigrok/hardware/common/usb.c

331 lines
9.1 KiB
C

/*
* This file is part of the libsigrok project.
*
* Copyright (C) 2012 Uwe Hermann <uwe@hermann-uwe.de>
* Copyright (C) 2012 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 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 <glib.h>
#include <libusb.h>
#include "libsigrok.h"
#include "libsigrok-internal.h"
/* SR_CONF_CONN takes one of these: */
#define CONN_USB_VIDPID "^([0-9a-z]{4})\\.([0-9a-z]{4})$"
#define CONN_USB_BUSADDR "^(\\d+)\\.(\\d+)$"
/* Some USBTMC-specific enums, as defined in the USBTMC standard. */
#define SUBCLASS_USBTMC 0x03
#define USBTMC_USB488 0x01
#define LOG_PREFIX "usb"
/**
* Find USB devices according to a connection string.
*
* @param usb_ctx libusb context to use while scanning.
* @param conn Connection string specifying the device(s) to match. This
* can be of the form "<bus>.<address>", or "<vendorid>.<productid>".
*
* @return A GSList of struct sr_usb_dev_inst, with bus and address fields
* matching the device that matched the connection string. The GSList and
* its contents must be freed by the caller.
*/
SR_PRIV GSList *sr_usb_find(libusb_context *usb_ctx, const char *conn)
{
struct sr_usb_dev_inst *usb;
struct libusb_device **devlist;
struct libusb_device_descriptor des;
GSList *devices;
GRegex *reg;
GMatchInfo *match;
int vid, pid, bus, addr, b, a, ret, i;
char *mstr;
vid = pid = bus = addr = 0;
reg = g_regex_new(CONN_USB_VIDPID, 0, 0, NULL);
if (g_regex_match(reg, conn, 0, &match)) {
if ((mstr = g_match_info_fetch(match, 1)))
vid = strtoul(mstr, NULL, 16);
g_free(mstr);
if ((mstr = g_match_info_fetch(match, 2)))
pid = strtoul(mstr, NULL, 16);
g_free(mstr);
sr_dbg("Trying to find USB device with VID:PID = %04x:%04x.",
vid, pid);
} else {
g_match_info_unref(match);
g_regex_unref(reg);
reg = g_regex_new(CONN_USB_BUSADDR, 0, 0, NULL);
if (g_regex_match(reg, conn, 0, &match)) {
if ((mstr = g_match_info_fetch(match, 1)))
bus = strtoul(mstr, NULL, 10);
g_free(mstr);
if ((mstr = g_match_info_fetch(match, 2)))
addr = strtoul(mstr, NULL, 10);
g_free(mstr);
sr_dbg("Trying to find USB device with bus.address = "
"%d.%d.", bus, addr);
}
}
g_match_info_unref(match);
g_regex_unref(reg);
if (vid + pid + bus + addr == 0) {
sr_err("Neither VID:PID nor bus.address was specified.");
return NULL;
}
if (bus > 64) {
sr_err("Invalid bus specified: %d.", bus);
return NULL;
}
if (addr > 127) {
sr_err("Invalid address specified: %d.", addr);
return NULL;
}
/* Looks like a valid USB device specification, but is it connected? */
devices = NULL;
libusb_get_device_list(usb_ctx, &devlist);
for (i = 0; devlist[i]; i++) {
if ((ret = libusb_get_device_descriptor(devlist[i], &des))) {
sr_err("Failed to get device descriptor: %s.",
libusb_error_name(ret));
continue;
}
if (vid + pid && (des.idVendor != vid || des.idProduct != pid))
continue;
b = libusb_get_bus_number(devlist[i]);
a = libusb_get_device_address(devlist[i]);
if (bus + addr && (b != bus || a != addr))
continue;
sr_dbg("Found USB device (VID:PID = %04x:%04x, bus.address = "
"%d.%d).", des.idVendor, des.idProduct, b, a);
usb = sr_usb_dev_inst_new(libusb_get_bus_number(devlist[i]),
libusb_get_device_address(devlist[i]), NULL);
devices = g_slist_append(devices, usb);
}
libusb_free_device_list(devlist, 1);
sr_dbg("Found %d device(s).", g_slist_length(devices));
return devices;
}
/**
* Find USB devices supporting the USBTMC class
*
* @param usb_ctx libusb context to use while scanning.
*
* @return A GSList of struct sr_usb_dev_inst, with bus and address fields
* indicating devices with USBTMC support.
*/
SR_PRIV GSList *sr_usb_find_usbtmc(libusb_context *usb_ctx)
{
struct sr_usb_dev_inst *usb;
struct libusb_device **devlist;
struct libusb_device_descriptor des;
struct libusb_config_descriptor *confdes;
const struct libusb_interface_descriptor *intfdes;
GSList *devices;
int confidx, intfidx, ret, i;
devices = NULL;
libusb_get_device_list(usb_ctx, &devlist);
for (i = 0; devlist[i]; i++) {
if ((ret = libusb_get_device_descriptor(devlist[i], &des))) {
sr_err("Failed to get device descriptor: %s.",
libusb_error_name(ret));
continue;
}
for (confidx = 0; confidx < des.bNumConfigurations; confidx++) {
if (libusb_get_config_descriptor(devlist[i], confidx, &confdes) != 0) {
sr_err("Failed to get configuration descriptor.");
break;
}
for (intfidx = 0; intfidx < confdes->bNumInterfaces; intfidx++) {
intfdes = confdes->interface[intfidx].altsetting;
if (intfdes->bInterfaceClass != LIBUSB_CLASS_APPLICATION
|| intfdes->bInterfaceSubClass != SUBCLASS_USBTMC
|| intfdes->bInterfaceProtocol != USBTMC_USB488)
continue;
sr_dbg("Found USBTMC device (VID:PID = %04x:%04x, bus.address = "
"%d.%d).", des.idVendor, des.idProduct,
libusb_get_bus_number(devlist[i]),
libusb_get_device_address(devlist[i]));
usb = sr_usb_dev_inst_new(libusb_get_bus_number(devlist[i]),
libusb_get_device_address(devlist[i]), NULL);
devices = g_slist_append(devices, usb);
}
libusb_free_config_descriptor(confdes);
}
}
libusb_free_device_list(devlist, 1);
sr_dbg("Found %d device(s).", g_slist_length(devices));
return devices;
}
SR_PRIV int sr_usb_open(libusb_context *usb_ctx, struct sr_usb_dev_inst *usb)
{
struct libusb_device **devlist;
struct libusb_device_descriptor des;
int ret, r, cnt, i, a, b;
sr_dbg("Trying to open USB device %d.%d.", usb->bus, usb->address);
if ((cnt = libusb_get_device_list(usb_ctx, &devlist)) < 0) {
sr_err("Failed to retrieve device list: %s.",
libusb_error_name(cnt));
return SR_ERR;
}
ret = SR_ERR;
for (i = 0; i < cnt; i++) {
if ((r = libusb_get_device_descriptor(devlist[i], &des)) < 0) {
sr_err("Failed to get device descriptor: %s.",
libusb_error_name(r));
continue;
}
b = libusb_get_bus_number(devlist[i]);
a = libusb_get_device_address(devlist[i]);
if (b != usb->bus || a != usb->address)
continue;
if ((r = libusb_open(devlist[i], &usb->devhdl)) < 0) {
sr_err("Failed to open device: %s.",
libusb_error_name(r));
break;
}
sr_dbg("Opened USB device (VID:PID = %04x:%04x, bus.address = "
"%d.%d).", des.idVendor, des.idProduct, b, a);
ret = SR_OK;
break;
}
libusb_free_device_list(devlist, 1);
return ret;
}
#ifdef _WIN32
static gpointer usb_thread(gpointer data)
{
struct sr_context *ctx = data;
while (ctx->usb_thread_running) {
g_mutex_lock(&ctx->usb_mutex);
libusb_wait_for_event(ctx->libusb_ctx, NULL);
SetEvent(ctx->usb_event);
g_mutex_unlock(&ctx->usb_mutex);
g_thread_yield();
}
return NULL;
}
static int usb_callback(int fd, int revents, void *cb_data)
{
struct sr_context *ctx = cb_data;
int ret;
g_mutex_lock(&ctx->usb_mutex);
ret = ctx->usb_cb(fd, revents, ctx->usb_cb_data);
if (ctx->usb_thread_running) {
ResetEvent(ctx->usb_event);
g_mutex_unlock(&ctx->usb_mutex);
}
return ret;
}
#endif
SR_PRIV int usb_source_add(struct sr_context *ctx, int timeout,
sr_receive_data_callback_t cb, void *cb_data)
{
if (ctx->usb_source_present) {
sr_err("A USB event source is already present.");
return SR_ERR;
}
#ifdef _WIN32
ctx->usb_event = CreateEvent(NULL, TRUE, FALSE, NULL);
g_mutex_init(&ctx->usb_mutex);
ctx->usb_thread_running = TRUE;
ctx->usb_thread = g_thread_new("usb", usb_thread, ctx);
ctx->usb_pollfd.fd = ctx->usb_event;
ctx->usb_pollfd.events = G_IO_IN;
ctx->usb_cb = cb;
ctx->usb_cb_data = cb_data;
sr_session_source_add_pollfd(&ctx->usb_pollfd, timeout, usb_callback, ctx);
#else
const struct libusb_pollfd **lupfd;
unsigned int i;
lupfd = libusb_get_pollfds(ctx->libusb_ctx);
for (i = 0; lupfd[i]; i++)
sr_source_add(lupfd[i]->fd, lupfd[i]->events, timeout, cb, cb_data);
free(lupfd);
#endif
ctx->usb_source_present = TRUE;
return SR_OK;
}
SR_PRIV int usb_source_remove(struct sr_context *ctx)
{
if (!ctx->usb_source_present)
return SR_OK;
#ifdef _WIN32
ctx->usb_thread_running = FALSE;
g_mutex_unlock(&ctx->usb_mutex);
libusb_unlock_events(ctx->libusb_ctx);
g_thread_join(ctx->usb_thread);
g_mutex_clear(&ctx->usb_mutex);
sr_session_source_remove_pollfd(&ctx->usb_pollfd);
CloseHandle(ctx->usb_event);
#else
const struct libusb_pollfd **lupfd;
unsigned int i;
lupfd = libusb_get_pollfds(ctx->libusb_ctx);
for (i = 0; lupfd[i]; i++)
sr_source_remove(lupfd[i]->fd);
free(lupfd);
#endif
ctx->usb_source_present = FALSE;
return SR_OK;
}