ipad_charge.c

#include <getopt.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <libusb-1.0/libusb.h>

#define VERSION "1.3"

#define CTRL_OUT	(LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_ENDPOINT_OUT)
#define VENDOR_APPLE		0x05ac
#define PRODUCT_IPAD1		0x129a
#define PRODUCT_IPAD2		0x129f
#define PRODUCT_IPAD2_3G	0x12a2
#define PRODUCT_IPAD3       0x12a4

int set_charging_mode(libusb_device *dev, bool enable) {
    int ret;
    struct libusb_device_handle *dev_handle;

    if ((ret = libusb_open(dev, &dev_handle)) < 0) {
        fprintf(stderr, "ipad_charge: unable to open device: error %d\n", ret);
        return ret;
    }

    if ((ret = libusb_claim_interface(dev_handle, 0)) < 0) {
        fprintf(stderr, "ipad_charge: unable to claim interface: error %d\n", ret);
        goto out_close;
    }

    if ((ret = libusb_control_transfer(dev_handle, CTRL_OUT, 0x40, 0x6400, enable ? 0x6400 : 0, NULL, 0, 2000)) < 0) {
        fprintf(stderr, "ipad_charge: unable to send command: error %d\n", ret);
        goto out_release;
    }

    ret = 0;

out_release:
    libusb_release_interface(dev_handle, 0);
out_close:
    libusb_close(dev_handle);

    return ret;
}

void help(char *progname) {
    printf("Usage: %s [OPTION]\n", progname);
    printf("iPad USB charging control utility\n\n");
    printf("Available OPTIONs:\n");
    printf("  -0, --off\t\t\tdisable charging instead of enabling it\n");
    printf("  -h, --help\t\t\tdisplay this help and exit\n");
    printf("  -V, --version\t\t\tdisplay version information and exit\n");
    printf("\nExamples:\n");
    printf("  ipad_charge\t\t\t\t\tenable charging on all connected iPads\n");
    printf("  BUSNUM=004 DEVNUM=014 ipad_charge -off\tdisable charging on iPad connected on bus 4, device 14\n");
}

void version() {
    printf("ipad_charge v%s - iPad USB charging control utility\n", VERSION);
    printf("Copyright (c) 2010 Ondrej Zary - http://www.rainbow-software.org\n");
    printf("License: GLPv2\n");
}

int main(int argc, char *argv[]) {
    int ret, devnum = 0, busnum = 0;
    bool enable = 1;

    while (1) {
        struct option long_options[] = {
            { .name = "off",	.has_arg = 0, .val = '0' },
            { .name = "help",	.has_arg = 0, .val = 'h' },
            { .name = "version",	.has_arg = 0, .val = 'V' },
            { .name = NULL },
        };
        int opt = getopt_long(argc, argv, "0hV", long_options, NULL);
        if (opt < 0)
            break;
        switch (opt) {
            case '0':
                enable = 0;
                break;
            case 'h':
                help(argv[0]);
                exit(0);
            case 'V':
                version();
                exit(0);
            default:
                fprintf(stderr, "Try '%s --help' for more information.\n", argv[0]);
                exit(100);
        }
    }

    if (getenv("BUSNUM") && getenv("DEVNUM")) {
        busnum = atoi(getenv("BUSNUM"));
        devnum = atoi(getenv("DEVNUM"));
    }

    if (libusb_init(NULL) < 0) {
        fprintf(stderr, "ipad_charge: failed to initialise libusb\n");
        exit(1);
    }

    libusb_device **devs;
    if (libusb_get_device_list(NULL, &devs) < 0) {
        fprintf(stderr, "ipad_charge: unable to enumerate USB devices\n");
        ret = 2;
        goto out_exit;
    }

    libusb_device *dev;
    int i = 0, count = 0;
    /* if BUSNUM and DEVNUM were specified (by udev), find device by address */
    if (busnum && devnum) {
        while ((dev = devs[i++]) != NULL) {
            if (libusb_get_bus_number(dev) == busnum &&
                    libusb_get_device_address(dev) == devnum) {
                if (set_charging_mode(dev, enable) < 0)
                    fprintf(stderr, "ipad_charge: error setting charge mode\n");
                else
                    count++;
                break;
            }
        }
        /* otherwise apply to all devices */
    } else {
        while ((dev = devs[i++]) != NULL) {
            struct libusb_device_descriptor desc;
            if ((ret = libusb_get_device_descriptor(dev, &desc)) < 0) {
                fprintf(stderr, "ipad_charge: failed to get device descriptor: error %d\n", ret);
                continue;
            }
            if (desc.idVendor == VENDOR_APPLE && (desc.idProduct == PRODUCT_IPAD1 || desc.idProduct == PRODUCT_IPAD2 || desc.idProduct == PRODUCT_IPAD2_3G || desc.idProduct == PRODUCT_IPAD3 )) {
                if (set_charging_mode(dev, enable) < 0)
                    fprintf(stderr, "ipad_charge: error setting charge mode\n");
                else
                    count++;
            }
        }
    }

    if (count < 1) {
        fprintf(stderr, "ipad_charge: no such device or an error occured\n");
        ret = 3;
    } else
        ret = 0;

    libusb_free_device_list(devs, 1);
out_exit:
    libusb_exit(NULL);

    return ret;
}