[src/trunk]: src/sys/dev set hwif_softc around midi_attach()s call to ->getin...

[mrg <mrg%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/4b656e6791ed
branches:  trunk
changeset: 771524:4b656e6791ed
user:      mrg <mrg%NetBSD.org@localhost>
date:      Thu Nov 24 02:54:32 2011 +0000

description:
set hwif_softc around midi_attach()s call to ->getinfo(), like the old
code, so that midi_register_hw_if_ext() works.  add a mutex for this
to avoid multiple midi_attach()s fighting over it.

XXX: this is an ugly interface

diffstat:

 sys/dev/midi.c |  15 +++++++++++++--
 1 files changed, 13 insertions(+), 2 deletions(-)

diffs (53 lines):

diff -r c343178db88a -r 4b656e6791ed sys/dev/midi.c
--- a/sys/dev/midi.c    Thu Nov 24 01:59:25 2011 +0000
+++ b/sys/dev/midi.c    Thu Nov 24 02:54:32 2011 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: midi.c,v 1.73 2011/11/23 23:07:31 jmcneill Exp $       */
+/*     $NetBSD: midi.c,v 1.74 2011/11/24 02:54:32 mrg Exp $    */
 
 /*
  * Copyright (c) 1998, 2008 The NetBSD Foundation, Inc.
@@ -31,7 +31,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: midi.c,v 1.73 2011/11/23 23:07:31 jmcneill Exp $");
+__KERNEL_RCSID(0, "$NetBSD: midi.c,v 1.74 2011/11/24 02:54:32 mrg Exp $");
 
 #include "midi.h"
 #include "sequencer.h"
@@ -81,6 +81,7 @@
 #endif
 
 static struct midi_softc *hwif_softc = NULL;
+static kmutex_t hwif_softc_lock;
 
 static void    midi_in(void *, int);
 static void    midi_out(void *);
@@ -242,6 +243,12 @@
 {
        struct midi_info mi;
        kmutex_t *dummy;
+       static int first = 1;
+
+       if (first) {
+               mutex_init(&hwif_softc_lock, MUTEX_DEFAULT, IPL_NONE);
+               first = 0;
+       }
 
        sc->hw_if->get_locks(sc->hw_hdl, &sc->lock, &dummy);
 
@@ -260,9 +267,13 @@
        sc->isopen = 0;
        sc->sc_dev = parent;
 
+       mutex_enter(&hwif_softc_lock);
        mutex_enter(sc->lock);
+       hwif_softc = sc;
        sc->hw_if->getinfo(sc->hw_hdl, &mi);
+       hwif_softc = NULL;
        mutex_exit(sc->lock);
+       mutex_exit(&hwif_softc_lock);
 
        sc->props = mi.props;