Я хочу использовать библиотеку libusb для написания некоторых тестовых приложений для USB.
Кто-нибудь может подсказать, как настроить передачу управления с помощью вызова usb_control_msg?
Я получаю ошибку плохого дескриптора при выполнении следующего кода.
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include "usb.h"
static int vendor_id;
static int product_id;
typedef struct{
int requesttype;
int request;
int value;
int index;
char *bytes;
int size;
int timeout;
}ctrlmsg_param;
void print_endpoint(struct usb_endpoint_descriptor *endpoint)
{
printf("=====End point Information====\n");
printf("bEndpointAddress: %x\n", endpoint->bEndpointAddress);
printf("bmAttributes: %x\n", endpoint->bmAttributes);
printf("wMaxPacketSize: %d\n", endpoint->wMaxPacketSize);
printf("bInterval: %d\n", endpoint->bInterval);
printf("bRefresh: %d\n", endpoint->bRefresh);
printf("bSynchAddress: %d\n", endpoint->bSynchAddress);
}
void print_altsetting(struct usb_interface_descriptor *interface)
{
int i;
printf("\n=====Alternate Setting Information====\n");
printf("bInterfaceNumber: %d\n", interface->bInterfaceNumber);
printf("bAlternateSetting: %d\n", interface->bAlternateSetting);
printf("bNumEndpoints: %d\n", interface->bNumEndpoints);
printf("bInterfaceClass: %d\n", interface->bInterfaceClass);
printf("bInterfaceSubClass: %d\n", interface->bInterfaceSubClass);
printf("bInterfaceProtocol: %d\n", interface->bInterfaceProtocol);
printf("iInterface: %d\n", interface->iInterface);
for (i = 0; i < interface->bNumEndpoints; i++)
print_endpoint(&interface->endpoint[i]);
}
void print_interface(struct usb_interface *interface)
{
int i;
for (i = 0; i < interface->num_altsetting; i++)
print_altsetting(&interface->altsetting[i]);
}
void print_configuration(struct usb_config_descriptor *config)
{
int i;
printf("=====Configuration Information====\n");
printf("wTotalLength: %d\n", config->wTotalLength);
printf("bNumInterfaces: %d\n", config->bNumInterfaces);
printf("bConfigurationValue: %d\n", config->bConfigurationValue);
printf("iConfiguration: %d\n", config->iConfiguration);
printf("bmAttributes: %x\n", config->bmAttributes);
printf("MaxPower: %d\n", config->MaxPower);
for (i = 0; i < config->bNumInterfaces; i++)
print_interface(&config->interface[i]);
}
int print_device(struct usb_device *dev)
{
usb_dev_handle *udev;
char str[100];
int ret, i;
udev = usb_open(dev);
if (udev) {
if (dev->descriptor.iManufacturer) {
ret = usb_get_string_simple(udev, dev->descriptor.iManufacturer, str, sizeof(str));
if (ret > 0)
{
printf("Manufacturer is %s\n",str);
}
}
if (dev->descriptor.iProduct) {
ret = usb_get_string_simple(udev, dev->descriptor.iProduct, str, sizeof(str));
if (ret > 0)
{
printf("Product is %s\n",str);
}
}
}
if (udev)
usb_close(udev);
printf("Possible configurations are %x\n",dev->descriptor.bNumConfigurations);
sleep(2);
for (i = 0; i < dev->descriptor.bNumConfigurations; i++)
print_configuration(&dev->config[i]);
return 0;
}
int htod( const char* str )
{
int decimal;
sscanf( str, "%x", &decimal);
return decimal;
}
void set_data(struct usb_device *dev)
{
ctrlmsg_param param;
param.requesttype= 0;
param.request=0;
param.value=0;
param.index=0;
param.bytes=10;
param.size=0;
param.timeout=5000;
usb_control_msg(dev, param.requesttype, param.request, param.value, param.index, param.bytes, param.size, param.timeout);
printf("error is %s\n",strerror(errno));
return;
}
int main(int argc, char *argv[])
{
struct usb_bus *bus;
struct usb_device *dev;
if(argc != 3)
{
printf("Error in number of arguments\n");
printf("Usage:./usb_info <vendor id> <product id>\n");
exit(0);
}
vendor_id=htod(argv[1]);
product_id=htod(argv[2]);
printf("initializing USB library\n");
usb_init();
printf("Finding Buses and Devices\n");
usb_find_busses();
usb_find_devices();
for (bus = usb_get_busses(); bus; bus = bus->next) {
for (dev = bus->devices; dev; dev = dev->next) {
if ((dev->descriptor.idProduct == product_id) && (dev->descriptor.idVendor == vendor_id)){
printf("Found device with produxt id %x and vendor id %x\n",product_id,vendor_id);
print_device(dev);
set_data(dev);
print_device(dev);
}
}
}
return 0;
}
С уважением,
Sandeep