usb.c

linux 安装程序

/*
 * usb.c - usb probing/module loading functionality
 *
 * Erik Troan <[e-mail]>
 * Matt Wilson <[e-mail]>
 * Michael Fulbright <[e-mail]>
 * Jeremy Katz <[e-mail]>
 *
 * Copyright 1999 - 2003 Red Hat, Inc.
 *
 * This software may be freely redistributed under the terms of the GNU
 * General Public License.
 *
 * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <alloca.h>
#include <errno.h>
#include <fcntl.h>
#include <kudzu/kudzu.h>
#include <sys/stat.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "loader.h"
#include "log.h"
#include "modules.h"
#include "moduledeps.h"

#include "../isys/imount.h"

/* boot flags */
extern int flags;

/* This forces a pause between initializing usb and trusting the /proc 
   stuff */
void sleepUntilUsbIsStable(void) {
    struct stat sb;
    time_t last = 0;
    int i, count = 0;

    /* sleep for a maximum of 20 seconds, minimum of 2 seconds */
    logMessage(DEBUGLVL, "waiting for usb to become stable...");
    for (i = 0; i < 20; i++) {
	stat("/proc/bus/usb/devices", &sb);
	if (last == sb.st_mtime) {
	    count++;
	    /* if we get the same mtime twice in a row, should be
	       good enough to use now */
	    if (count > 1)
		break;
	} else {
	    /* if we didn't match mtimes, reset the stability counter */
	    count = 0;
	}
	last = sb.st_mtime;
	sleep(1);
    }
    logMessage(DEBUGLVL, "%d seconds.", i);
}

int usbInitialize(moduleList modLoaded, moduleDeps modDeps,
			 moduleInfoSet modInfo) {
    struct device ** devices;
    char * buf;
    int i;
    char * loadUsbStorage = NULL;

    if (FL_NOUSB(flags)) return 0;

    logMessage(INFO, "looking for usb controllers");

    devices = probeDevices(CLASS_USB, BUS_PCI | BUS_PS3, 0);

    if (!devices) {
        logMessage(DEBUGLVL, "no usb controller found");
        return 0;
    }

    /* JKFIXME: if we looked for all of them, we could batch this up and it
     * would be faster */
    for (i=0; devices[i]; i++) {
        if (!devices[i]->driver) continue;
        logMessage(INFO, "found USB controller %s", devices[i]->driver);

        if (mlLoadModuleSet(devices[i]->driver, modLoaded, modDeps, modInfo)) {
            /* dont return, just keep going. */
            /* may have USB built into kernel */
            /* return 1; */
        }

    }
    free(devices);


    if (FL_TESTING(flags)) return 0;

    if (doPwMount("/proc/bus/usb", "/proc/bus/usb", "usbfs", 0, NULL))
	logMessage(ERROR, "failed to mount device usbfs: %s", strerror(errno));

    /* sleep so we make sure usb devices get properly enumerated.
       that way we should block when initializing each usb driver until
       the device is ready for use */
    sleepUntilUsbIsStable();

    if (!FL_NOUSBSTORAGE(flags)) {
        devices = probeDevices(CLASS_HD | CLASS_FLOPPY | CLASS_CDROM, 
                               BUS_USB, PROBE_ALL);
        if (devices) {
            /*            if (FL_UB(flags))
                loadUsbStorage = ":ub";
                else */
                loadUsbStorage = ":usb-storage";
            free(devices);
        }
    }

    buf = alloca(40);
    sprintf(buf, "hid:keybdev%s", (loadUsbStorage ? loadUsbStorage : ""));
    mlLoadModuleSet(buf, modLoaded, modDeps, modInfo);
    sleep(1);

    return 0;
}

void usbInitializeMouse(moduleList modLoaded, moduleDeps modDeps,
                        moduleInfoSet modInfo) {
    if (FL_NOUSB(flags)) return;

    logMessage(INFO, "looking for USB mouse...");
    if (probeDevices(CLASS_MOUSE, BUS_USB, PROBE_ALL)) {
        logMessage(INFO, "USB mouse found, loading mousedev module");
        if (mlLoadModuleSet("mousedev:appletouch", modLoaded, modDeps, modInfo)) {
            logMessage (DEBUGLVL, "failed to loading mousedev module");
            return;
        }
    }
}