Read status register after all writes to the pcf8584 controller. Alegedly

this is what (Open)Solaris does and it makes the i2c controller on the
blade2.5k work.  From NetBSD.

Tested by sthen@, ok deraadt@

diff --git a/sys/dev/ic/pcf8584.c b/sys/dev/ic/pcf8584.c
index 949e5eb..b86f6fe 100644 (file)
--- a/sys/dev/ic/pcf8584.c
+++ b/sys/dev/ic/pcf8584.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: pcf8584.c,v 1.10 2010/04/30 15:18:29 kettenis Exp $ */
+/*     $OpenBSD: pcf8584.c,v 1.11 2010/08/01 18:48:41 kettenis Exp $ */
 
 /*
  * Copyright (c) 2006 David Gwynne <dlg@openbsd.org>
@@ -275,8 +275,9 @@ void
 pcfiic_write(struct pcfiic_softc *sc, bus_size_t r, u_int8_t v)
 {
        bus_space_write_1(sc->sc_iot, sc->sc_ioh, sc->sc_regmap[r], v);
-       bus_space_barrier(sc->sc_iot, sc->sc_ioh, sc->sc_regmap[r], 1,
-           BUS_SPACE_BARRIER_WRITE);
+       bus_space_barrier(sc->sc_iot, sc->sc_ioh, 0, 4,
+           BUS_SPACE_BARRIER_WRITE | BUS_SPACE_BARRIER_READ);
+       bus_space_read_1(sc->sc_iot, sc->sc_ioh, sc->sc_regmap[PCF_S1]);
 }
 
 void