Remember the error of ucomreadcb() for the next ucomread() call and returns an

EIO.  Thus the userland notices the error and closes the device.  We forget the
error on reopen and the device works again.

Ok mbuhl

diff --git a/sys/dev/usb/ucom.c b/sys/dev/usb/ucom.c
index ed3a2a4..e2e41ce 100644 (file)
--- a/sys/dev/usb/ucom.c
+++ b/sys/dev/usb/ucom.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: ucom.c,v 1.72 2022/04/09 20:07:44 naddy Exp $ */
+/*     $OpenBSD: ucom.c,v 1.73 2022/06/27 13:14:49 jan Exp $ */
 /*     $NetBSD: ucom.c,v 1.49 2003/01/01 00:10:25 thorpej Exp $        */
 
 /*
@@ -114,6 +114,7 @@ struct ucom_softc {
        int                     sc_swflags;
 
        u_char                  sc_cua;
+       int                     sc_error;
 
        struct rwlock           sc_lock;        /* lock during open */
        int                     sc_open;
@@ -307,6 +308,8 @@ ucomopen(dev_t dev, int flag, int mode, struct proc *p)
        if (sc == NULL)
                return (ENXIO);
 
+       sc->sc_error = 0;
+
        if (usbd_is_dying(sc->sc_uparent))
                return (EIO);
 
@@ -606,6 +609,9 @@ ucomread(dev_t dev, struct uio *uio, int flag)
        if (sc == NULL || usbd_is_dying(sc->sc_uparent))
                return (EIO);
 
+       if (sc->sc_error)
+               return (sc->sc_error);
+
        sc->sc_refcnt++;
        tp = sc->sc_tty;
        error = (*LINESW(tp, l_read))(tp, uio, flag);
@@ -1144,6 +1150,7 @@ ucomreadcb(struct usbd_xfer *xfer, void *p, usbd_status status)
            usbd_is_dying(sc->sc_uparent)) {
                DPRINTF(("ucomreadcb: dying\n"));
                /* Send something to wake upper layer */
+               sc->sc_error = EIO;
                s = spltty();
                (*rint)('\n', tp);
                ttwakeup(tp);