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ペンドライブで読み取りおよび書き込み操作を実行しようとしています。

詳細:ベンダーID:8564および製品ID:1000。これは、トランセンドのJetFlashマスストレージデバイスです。

私はペンドライブで読み取り/書き込みを実現できるかどうかを知りたいと思っています。もしそうなら、それは私が以下に提供されたコードで試したように起こるだろうか?

デバイスID、製品ID、エンドポイントアドレスを取得する方法を学びました。これは私が実装したものです。

ここで、デバイスが確認されて開かれます。そして、インターフェースでさえ、それが成功したと主張しています。

ただし、バルク伝達関数は-1を返します。

説明は何ですか?

#include <stdio.h>
#include <sys/types.h>
#include <string.h>
#include </usr/include/libusb-1.0/libusb.h>

#define BULK_EP_OUT     0x82
#define BULK_EP_IN      0x02

int main(void)
{
    int r = 0, e = 0;
    struct libusb_device_handle *handle = NULL;
    struct libusb_device **devs;
    struct libusb_device *dev;
    struct libusb_device_descriptor desc;
    char str1[256], str2[256];

    /* Init libusb */
    r = libusb_init(NULL);
    if (r < 0)
    {
        printf("\nfailed to initialise libusb\n");
        return 1;
    }

    handle = libusb_open_device_with_vid_pid(NULL, 0x8564, 0x1000);
    if(handle == NULL)
    {
        printf("\nError in device opening!");
    }
    else
        printf("\nDevice Opened");

    // Tell libusb to use the CONFIGNUM configuration of the device

    libusb_set_configuration(handle, 1);
    if(libusb_kernel_driver_active(handle, 0) == 1)
    {
        printf("\nKernel Driver Active");
        if(libusb_detach_kernel_driver(handle, 0) == 0)
            printf("\nKernel Driver Detached!");
    }

    e = libusb_claim_interface(handle, 0);
    if(e < 0)
    {
        printf("\nCannot Claim Interface");
    }
    else
        printf("\nClaimed Interface");

      /* Communicate */

    int bytes_read;
    int nbytes = 256;
    unsigned char *my_string, *my_string1;
    int transferred = 0;
    my_string = (unsigned char *) malloc (nbytes + 1);
    my_string1 = (unsigned char *) malloc (nbytes + 1);

    strcpy(my_string, "divesd");
    printf("\nTo be sent : %s", my_string);

    e = libusb_bulk_transfer(handle, BULK_EP_OUT, my_string, bytes_read, &transferred, 5000);
    printf("\nXfer returned with %d", e);
    printf("\nSent %d bytes with string: %s\n", transferred, my_string);

    libusb_bulk_transfer(handle, BULK_EP_IN, my_string1, 256, &transferred, 5000);
    printf("\nXfer returned with %d", e);     //It returns -1... This is an error, I guess.
    printf("\nReceived %d bytes with string: %s\n", transferred, my_string1);

    e = libusb_release_interface(handle, 0);
    libusb_close(handle);
    libusb_exit(NULL);
    return 0;
}
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1 に答える 1

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以下のコードを試すと、LPC2148で動作するはずです。(ユーザー空間から) 書き込みが発生し、RTC が実行を開始した後、USB から割り込みを受信するように構成された LPC2148 でこれをテストしました。

読み取り/書き込みにカーネル ドライバーが含まれているかどうかの質問への回答: 私が調べた限りでは、カーネル ドライバーを切り離し、libusb API を使用してインターフェイスを要求する必要があります。取り外さなくてもできるかどうかはわかりませんが。

#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <string.h>
#include </usr/local/include/libusb-1.0/libusb.h>

#define BULK_EP_OUT     0x82
#define BULK_EP_IN      0x08

int interface_ref = 0;
int alt_interface, interface_number;

int print_configuration(struct libusb_device_handle *hDevice, struct libusb_config_descriptor *config)
{
    char *data;
    int index;

    data = (char *)malloc(512);
    memset(data, 0, 512);

    index = config->iConfiguration;

    libusb_get_string_descriptor_ascii(hDevice, index, data, 512);

    printf("\nInterface Descriptors: ");
    printf("\n\tNumber of Interfaces: %d", config->bNumInterfaces);
    printf("\n\tLength: %d", config->bLength);
    printf("\n\tDesc_Type: %d", config->bDescriptorType);
    printf("\n\tConfig_index: %d", config->iConfiguration);
    printf("\n\tTotal length: %lu", config->wTotalLength);
    printf("\n\tConfiguration Value: %d", config->bConfigurationValue);
    printf("\n\tConfiguration Attributes: %d", config->bmAttributes);
    printf("\n\tMaxPower(mA): %d\n", config->MaxPower);

    free(data);
    data = NULL;
    return 0;
}

struct libusb_endpoint_descriptor* active_config(struct libusb_device *dev, struct libusb_device_handle *handle)
{
    struct libusb_device_handle *hDevice_req;
    struct libusb_config_descriptor *config;
    struct libusb_endpoint_descriptor *endpoint;
    int altsetting_index, interface_index=0, ret_active;
    int i, ret_print;

    hDevice_req = handle;

    ret_active = libusb_get_active_config_descriptor(dev, &config);
    ret_print = print_configuration(hDevice_req, config);

    for (interface_index=0;interface_index<config->bNumInterfaces;interface_index++)
    {
        const struct libusb_interface *iface = &config->interface[interface_index];
        for (altsetting_index=0; altsetting_index<iface->num_altsetting; altsetting_index++)
        {
            const struct libusb_interface_descriptor *altsetting = &iface->altsetting[altsetting_index];

            int endpoint_index;
            for(endpoint_index=0; endpoint_index<altsetting->bNumEndpoints; endpoint_index++)
            {
                const struct libusb_endpoint_desriptor *ep = &altsetting->endpoint[endpoint_index];
                endpoint = ep;
                alt_interface = altsetting->bAlternateSetting;
                interface_number = altsetting->bInterfaceNumber;
            }

            printf("\nEndPoint Descriptors: ");
            printf("\n\tSize of EndPoint Descriptor: %d", endpoint->bLength);
            printf("\n\tType of Descriptor: %d", endpoint->bDescriptorType);
            printf("\n\tEndpoint Address: 0x0%x", endpoint->bEndpointAddress);
            printf("\n\tMaximum Packet Size: %x", endpoint->wMaxPacketSize);
            printf("\n\tAttributes applied to Endpoint: %d", endpoint->bmAttributes);
            printf("\n\tInterval for Polling for data Tranfer: %d\n", endpoint->bInterval);
        }
    }
    libusb_free_config_descriptor(NULL);
    return endpoint;
}

int main(void)
{
    int r = 1;
    struct libusb_device **devs;
    struct libusb_device_handle *handle = NULL, *hDevice_expected = NULL;
    struct libusb_device *dev, *dev_expected;

    struct libusb_device_descriptor desc;
    struct libusb_endpoint_descriptor *epdesc;
    struct libusb_interface_descriptor *intdesc;

    ssize_t cnt;
    int e = 0, config2;
    int i = 0, index;
    char str1[64], str2[64];
    char found = 0;

    // Init libusb
    r = libusb_init(NULL);
    if(r < 0)
    {
        printf("\nFailed to initialise libusb\n");
        return 1;
    }
    else
        printf("\nInit successful!\n");

    // Get a list of USB devices
    cnt = libusb_get_device_list(NULL, &devs);
    if (cnt < 0)
    {
        printf("\nThere are no USB devices on the bus\n");
        return -1;
    }
    printf("\nDevice count: %d\n-------------------------------\n", cnt);

    while ((dev = devs[i++]) != NULL)
    {
        r = libusb_get_device_descriptor(dev, &desc);
        if (r < 0)
            {
            printf("Failed to get device descriptor\n");
            libusb_free_device_list(devs, 1);
            libusb_close(handle);
            break;
        }

        e = libusb_open(dev, &handle);
        if (e < 0)
        {
            printf("Error opening device\n");
            libusb_free_device_list(devs, 1);
            libusb_close(handle);
            break;
        }

        printf("\nDevice Descriptors: ");
        printf("\n\tVendor ID: %x", desc.idVendor);
        printf("\n\tProduct ID: %x", desc.idProduct);
        printf("\n\tSerial Number: %x", desc.iSerialNumber);
        printf("\n\tSize of Device Descriptor: %d", desc.bLength);
        printf("\n\tType of Descriptor: %d", desc.bDescriptorType);
        printf("\n\tUSB Specification Release Number: %d", desc.bcdUSB);
        printf("\n\tDevice Release Number: %d", desc.bcdDevice);
        printf("\n\tDevice Class: %d", desc.bDeviceClass);
        printf("\n\tDevice Sub-Class: %d", desc.bDeviceSubClass);
        printf("\n\tDevice Protocol: %d", desc.bDeviceProtocol);
        printf("\n\tMax. Packet Size: %d", desc.bMaxPacketSize0);
        printf("\n\tNumber of Configurations: %d\n", desc.bNumConfigurations);

        e = libusb_get_string_descriptor_ascii(handle, desc.iManufacturer, (unsigned char*) str1, sizeof(str1));
        if (e < 0)
        {
        libusb_free_device_list(devs, 1);
            libusb_close(handle);
            break;
        }
        printf("\nManufactured: %s", str1);

        e = libusb_get_string_descriptor_ascii(handle, desc.iProduct, (unsigned char*) str2, sizeof(str2));
        if(e < 0)
        {
        libusb_free_device_list(devs, 1);
            libusb_close(handle);
            break;
        }
        printf("\nProduct: %s", str2);
        printf("\n----------------------------------------");

        if(desc.idVendor == 0xffff && desc.idProduct == 0x4)
        {
           found = 1;
        break;
        }
    }//end of while
    if(found == 0)
    {
        printf("\nDevice NOT found\n");
        libusb_free_device_list(devs, 1);
        libusb_close(handle);
        return 1;
    }
    else
    {
        printf("\nDevice found");
        dev_expected = dev;
        hDevice_expected = handle;
    }

    e = libusb_get_configuration(handle, &config2);
    if(e!=0)
    {
        printf("\n***Error in libusb_get_configuration\n");
        libusb_free_device_list(devs, 1);
        libusb_close(handle);
        return -1;
    }
    printf("\nConfigured value: %d", config2);

    if(config2 != 1)
    {
        libusb_set_configuration(handle, 1);
        if(e!=0)
        {
            printf("Error in libusb_set_configuration\n");
            libusb_free_device_list(devs, 1);
            libusb_close(handle);
            return -1;
        }
        else
            printf("\nDevice is in configured state!");
    }

    libusb_free_device_list(devs, 1);

    if(libusb_kernel_driver_active(handle, 0) == 1)
    {
        printf("\nKernel Driver Active");
        if(libusb_detach_kernel_driver(handle, 0) == 0)
            printf("\nKernel Driver Detached!");
        else
        {
            printf("\nCouldn't detach kernel driver!\n");
            libusb_free_device_list(devs, 1);
            libusb_close(handle);
            return -1;
        }
    }

    e = libusb_claim_interface(handle, 0);
    if(e < 0)
    {
        printf("\nCannot Claim Interface");
        libusb_free_device_list(devs, 1);
        libusb_close(handle);
        return -1;
    }
    else
        printf("\nClaimed Interface\n");

    active_config(dev_expected, hDevice_expected);

    //   Communicate

    char *my_string, *my_string1;
    int transferred = 0;
    int received = 0;
    int length = 0;

    my_string = (char *)malloc(nbytes + 1);
    my_string1 = (char *)malloc(nbytes + 1);

    memset(my_string, '\0', 64);
    memset(my_string1, '\0', 64);

    strcpy(my_string, "Prasad Divesd");
    length = strlen(my_string);

    printf("\nTo be sent: %s", my_string);

    e = libusb_bulk_transfer(handle, BULK_EP_IN, my_string, length, &transferred, 0);
    if(e == 0 && transferred == length)
    {
        printf("\nWrite successful!");
        printf("\nSent %d bytes with string: %s\n", transferred, my_string);
    }
    else
        printf("\nError in write! e = %d and transferred = %d\n", e, transferred);

    sleep(3);
    i = 0;

    for(i = 0; i < length; i++)
    {
        e = libusb_bulk_transfer(handle, BULK_EP_OUT, my_string1, 64, &received, 0);  //64: Max Packet Length
        if(e == 0)
        {
            printf("\nReceived: ");
            printf("%c", my_string1[i]); //Will read a string from LPC2148
            sleep(1);
        }
        else
        {
            printf("\nError in read! e = %d and received = %d\n", e, received);
            return -1;
        }
    }

    e = libusb_release_interface(handle, 0);

    libusb_close(handle);
    libusb_exit(NULL);

    printf("\n");
    return 0;
}
于 2014-07-23T14:40:09.940 に答える