root/sys/dev/usb/uhid.c
/*      $OpenBSD: uhid.c,v 1.92 2024/12/30 02:46:00 guenther Exp $ */
/*      $NetBSD: uhid.c,v 1.57 2003/03/11 16:44:00 augustss Exp $       */

/*
 * Copyright (c) 1998 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Lennart Augustsson (lennart@augustsson.net) at
 * Carlstedt Research & Technology.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

/*
 * HID spec: https://www.usb.org/sites/default/files/hid1_11.pdf
 */

#include "fido.h"
#include "ujoy.h"

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/device.h>
#include <sys/conf.h>
#include <sys/tty.h>
#include <sys/selinfo.h>
#include <sys/vnode.h>

#include <dev/usb/usb.h>
#include <dev/usb/usbhid.h>

#include <dev/usb/usbdi.h>
#include <dev/usb/usbdi_util.h>

#include <dev/usb/uhidev.h>
#include <dev/usb/uhid.h>

#ifdef UHID_DEBUG
#define DPRINTF(x)      do { if (uhiddebug) printf x; } while (0)
#define DPRINTFN(n,x)   do { if (uhiddebug>(n)) printf x; } while (0)
int     uhiddebug = 0;
#else
#define DPRINTF(x)
#define DPRINTFN(n,x)
#endif

int uhid_match(struct device *, void *, void *);

struct cfdriver uhid_cd = { 
        NULL, "uhid", DV_DULL 
}; 

const struct cfattach uhid_ca = { 
        sizeof(struct uhid_softc), 
        uhid_match, 
        uhid_attach, 
        uhid_detach, 
};

struct uhid_softc *
uhid_lookup(dev_t dev)
{
        struct uhid_softc *sc = NULL;
        struct cdevsw *cdev;
        struct cfdriver *cd;

        cdev = &cdevsw[major(dev)];
        if (cdev->d_open == uhidopen)
                cd = &uhid_cd;
#if NFIDO > 0
        else if (cdev->d_open == fidoopen)
                cd = &fido_cd;
#endif
#if NUJOY > 0
        else if (cdev->d_open == ujoyopen)
                cd = &ujoy_cd;
#endif
        else
                return (NULL);
        if (UHIDUNIT(dev) < cd->cd_ndevs)
                sc = cd->cd_devs[UHIDUNIT(dev)];

        return (sc);
}

int
uhid_match(struct device *parent, void *match, void *aux)
{
        struct uhidev_attach_arg *uha = aux;

        if (UHIDEV_CLAIM_MULTIPLE_REPORTID(uha))
                return (UMATCH_NONE);

        return (UMATCH_IFACECLASS_GENERIC);
}

void
uhid_attach(struct device *parent, struct device *self, void *aux)
{
        struct uhid_softc *sc = (struct uhid_softc *)self;
        struct uhidev_attach_arg *uha = (struct uhidev_attach_arg *)aux;
        int size, repid;
        void *desc;

        sc->sc_hdev.sc_intr = uhid_intr;
        sc->sc_hdev.sc_parent = uha->parent;
        sc->sc_hdev.sc_udev = uha->uaa->device;
        sc->sc_hdev.sc_report_id = uha->reportid;

        uhidev_get_report_desc(uha->parent, &desc, &size);
        repid = uha->reportid;
        sc->sc_hdev.sc_isize = hid_report_size(desc, size, hid_input, repid);
        sc->sc_hdev.sc_osize = hid_report_size(desc, size, hid_output, repid);
        sc->sc_hdev.sc_fsize = hid_report_size(desc, size, hid_feature, repid);

        printf(": input=%d, output=%d, feature=%d\n",
            sc->sc_hdev.sc_isize, sc->sc_hdev.sc_osize, sc->sc_hdev.sc_fsize);
}

int
uhid_detach(struct device *self, int flags)
{
        struct uhid_softc *sc = (struct uhid_softc *)self;
        int s;
        int maj, mn;

        DPRINTF(("uhid_detach: sc=%p flags=%d\n", sc, flags));

        if (sc->sc_hdev.sc_state & UHIDEV_OPEN) {
                s = splusb();
                if (--sc->sc_refcnt >= 0) {
                        /* Wake everyone */
                        wakeup(&sc->sc_q);
                        /* Wait for processes to go away. */
                        usb_detach_wait(&sc->sc_hdev.sc_dev);
                }
                splx(s);
        }

        /* locate the major number */
        for (maj = 0; maj < nchrdev; maj++)
                if (cdevsw[maj].d_open == uhidopen)
                        break;

        /* Nuke the vnodes for any open instances (calls close). */
        mn = self->dv_unit;
        vdevgone(maj, mn, mn, VCHR);

        s = splusb();
        klist_invalidate(&sc->sc_rsel.si_note);
        splx(s);

        return (0);
}

void
uhid_intr(struct uhidev *addr, void *data, u_int len)
{
        struct uhid_softc *sc = (struct uhid_softc *)addr;

#ifdef UHID_DEBUG
        if (uhiddebug > 5) {
                u_int32_t i;

                DPRINTF(("uhid_intr: data ="));
                for (i = 0; i < len; i++)
                        DPRINTF((" %02x", ((u_char *)data)[i]));
                DPRINTF(("\n"));
        }
#endif

        (void)b_to_q(data, len, &sc->sc_q);

        if (sc->sc_state & UHID_ASLP) {
                sc->sc_state &= ~UHID_ASLP;
                DPRINTFN(5, ("uhid_intr: waking %p\n", &sc->sc_q));
                wakeup(&sc->sc_q);
        }
        selwakeup(&sc->sc_rsel);
}

int
uhidopen(dev_t dev, int flag, int mode, struct proc *p)
{
        return (uhid_do_open(dev, flag, mode, p));
}

int
uhid_do_open(dev_t dev, int flag, int mode, struct proc *p)
{
        struct uhid_softc *sc;
        int error;

        if ((sc = uhid_lookup(dev)) == NULL)
                return (ENXIO);

        DPRINTF(("uhidopen: sc=%p\n", sc));

        if (usbd_is_dying(sc->sc_hdev.sc_udev))
                return (ENXIO);

        if (sc->sc_hdev.sc_state & UHIDEV_OPEN)
                return (EBUSY);

        clalloc(&sc->sc_q, UHID_BSIZE, 0);

        error = uhidev_open(&sc->sc_hdev);
        if (error) {
                clfree(&sc->sc_q);
                return (error);
        }

        sc->sc_obuf = malloc(sc->sc_hdev.sc_osize, M_USBDEV, M_WAITOK);

        return (0);
}

int
uhidclose(dev_t dev, int flag, int mode, struct proc *p)
{
        struct uhid_softc *sc;

        if ((sc = uhid_lookup(dev)) == NULL)
                return (ENXIO);

        DPRINTF(("uhidclose: sc=%p\n", sc));

        clfree(&sc->sc_q);
        free(sc->sc_obuf, M_USBDEV, sc->sc_hdev.sc_osize);
        uhidev_close(&sc->sc_hdev);

        return (0);
}

int
uhid_do_read(struct uhid_softc *sc, struct uio *uio, int flag)
{
        int s;
        int error = 0;
        size_t length;
        u_char buffer[UHID_CHUNK];

        DPRINTFN(1, ("uhidread\n"));

        s = splusb();
        while (sc->sc_q.c_cc == 0) {
                if (flag & IO_NDELAY) {
                        splx(s);
                        return (EWOULDBLOCK);
                }
                sc->sc_state |= UHID_ASLP;
                DPRINTFN(5, ("uhidread: sleep on %p\n", &sc->sc_q));
                error = tsleep_nsec(&sc->sc_q, PZERO|PCATCH, "uhidrea", INFSLP);
                DPRINTFN(5, ("uhidread: woke, error=%d\n", error));
                if (usbd_is_dying(sc->sc_hdev.sc_udev))
                        error = EIO;
                if (error) {
                        sc->sc_state &= ~UHID_ASLP;
                        break;
                }
        }
        splx(s);

        /* Transfer as many chunks as possible. */
        while (sc->sc_q.c_cc > 0 && uio->uio_resid > 0 && !error) {
                length = ulmin(sc->sc_q.c_cc, uio->uio_resid);
                if (length > sizeof(buffer))
                        length = sizeof(buffer);

                /* Remove a small chunk from the input queue. */
                (void) q_to_b(&sc->sc_q, buffer, length);
                DPRINTFN(5, ("uhidread: got %zu chars\n", length));

                /* Copy the data to the user process. */
                if ((error = uiomove(buffer, length, uio)) != 0)
                        break;
        }

        return (error);
}

int
uhidread(dev_t dev, struct uio *uio, int flag)
{
        struct uhid_softc *sc;
        int error;

        if ((sc = uhid_lookup(dev)) == NULL)
                return (ENXIO);

        sc->sc_refcnt++;
        error = uhid_do_read(sc, uio, flag);
        if (--sc->sc_refcnt < 0)
                usb_detach_wakeup(&sc->sc_hdev.sc_dev);
        return (error);
}

int
uhid_do_write(struct uhid_softc *sc, struct uio *uio, int flag)
{
        int error;
        int size;

        DPRINTFN(1, ("uhidwrite\n"));

        if (usbd_is_dying(sc->sc_hdev.sc_udev))
                return (EIO);

        size = sc->sc_hdev.sc_osize;
        error = 0;
        if (uio->uio_resid > size)
                return (EMSGSIZE);
        else if (uio->uio_resid < size) {
                /* don't leak kernel memory to the USB device */
                memset(sc->sc_obuf + uio->uio_resid, 0, size - uio->uio_resid);
        }
        error = uiomove(sc->sc_obuf, uio->uio_resid, uio);
        if (!error) {
                if (uhidev_set_report(sc->sc_hdev.sc_parent,
                    UHID_OUTPUT_REPORT, sc->sc_hdev.sc_report_id, sc->sc_obuf,
                    size) != size)
                        error = EIO;
        }

        return (error);
}

int
uhidwrite(dev_t dev, struct uio *uio, int flag)
{
        struct uhid_softc *sc;
        int error;

        if ((sc = uhid_lookup(dev)) == NULL)
                return (ENXIO);

        sc->sc_refcnt++;
        error = uhid_do_write(sc, uio, flag);
        if (--sc->sc_refcnt < 0)
                usb_detach_wakeup(&sc->sc_hdev.sc_dev);
        return (error);
}

int
uhid_do_ioctl(struct uhid_softc *sc, u_long cmd, caddr_t addr,
              int flag, struct proc *p)
{
        int rc;

        DPRINTFN(2, ("uhidioctl: cmd=%lx\n", cmd));

        if (usbd_is_dying(sc->sc_hdev.sc_udev))
                return (EIO);

        switch (cmd) {
        case FIOASYNC:
                /* All handled in the upper FS layer. */
                break;

        case USB_GET_DEVICEINFO:
                usbd_fill_deviceinfo(sc->sc_hdev.sc_udev,
                                     (struct usb_device_info *)addr);
                break;

        case USB_GET_REPORT_DESC:
        case USB_GET_REPORT:
        case USB_SET_REPORT:
        case USB_GET_REPORT_ID:
        default:
                rc = uhidev_ioctl(&sc->sc_hdev, cmd, addr, flag, p);
                if (rc == -1)
                        rc = ENOTTY;
                return rc;
        }
        return (0);
}

int
uhidioctl(dev_t dev, u_long cmd, caddr_t addr, int flag, struct proc *p)
{
        struct uhid_softc *sc;
        int error;

        if ((sc = uhid_lookup(dev)) == NULL)
                return (ENXIO);

        sc->sc_refcnt++;
        error = uhid_do_ioctl(sc, cmd, addr, flag, p);
        if (--sc->sc_refcnt < 0)
                usb_detach_wakeup(&sc->sc_hdev.sc_dev);
        return (error);
}

void filt_uhidrdetach(struct knote *);
int filt_uhidread(struct knote *, long);
int uhidkqfilter(dev_t, struct knote *);

void
filt_uhidrdetach(struct knote *kn)
{
        struct uhid_softc *sc = (void *)kn->kn_hook;
        int s;

        s = splusb();
        klist_remove_locked(&sc->sc_rsel.si_note, kn);
        splx(s);
}

int
filt_uhidread(struct knote *kn, long hint)
{
        struct uhid_softc *sc = (void *)kn->kn_hook;

        kn->kn_data = sc->sc_q.c_cc;
        return (kn->kn_data > 0);
}

const struct filterops uhidread_filtops = {
        .f_flags        = FILTEROP_ISFD,
        .f_attach       = NULL,
        .f_detach       = filt_uhidrdetach,
        .f_event        = filt_uhidread,
};

int
uhidkqfilter(dev_t dev, struct knote *kn)
{
        struct uhid_softc *sc;
        struct klist *klist;
        int s;

        if ((sc = uhid_lookup(dev)) == NULL)
                return (ENXIO);

        if (usbd_is_dying(sc->sc_hdev.sc_udev))
                return (ENXIO);

        switch (kn->kn_filter) {
        case EVFILT_READ:
                klist = &sc->sc_rsel.si_note;
                kn->kn_fop = &uhidread_filtops;
                break;

        case EVFILT_WRITE:
                return (seltrue_kqfilter(dev, kn));

        default:
                return (EINVAL);
        }

        kn->kn_hook = (void *)sc;

        s = splusb();
        klist_insert_locked(klist, kn);
        splx(s);

        return (0);
}