Not all PS/2-like controllers accept the AUXECHO command, and the test that
pckbc applies in order to check for the presence of the auxiliary interface
may yield false negatives, even on newer hardware (see
https://marc.info/?l=openbsd-misc&m=158413132831425&w=2
).
This patch adds an alternative test. It is applied if AUXECHO fails, and
attempts to toggle and reset the KC8_MDISABLE flag by issuing an AUXDISABLE
and AUXENABLE command, which should only succeed if there's an AUX interface.
(The test has a branch which makes it work regardless of the initial state
of the flag; that's unnecessary at present but might be useful in a future
version.)
OK?
Index: pckbc.c
===================================================================
RCS file: /cvs/src/sys/dev/ic/pckbc.c,v
retrieving revision 1.53
diff -u -p -r1.53 pckbc.c
--- pckbc.c 30 Nov 2019 18:18:34 -0000 1.53
+++ pckbc.c 13 Sep 2020 09:27:10 -0000
@@ -295,6 +295,32 @@ pckbc_attach_slot(struct pckbc_softc *sc
return (found);
}
+int
+pckbc_auxcheck(struct pckbc_internal *t)
+{
+ bus_space_tag_t iot = t->t_iot;
+ bus_space_handle_t ioh_c = t->t_ioh_c;
+ int res = -1;
+
+ if ((t->t_cmdbyte & KC8_MDISABLE) == 0) {
+ if (pckbc_send_cmd(iot, ioh_c, KBC_AUXDISABLE)
+ && pckbc_get8042cmd(t))
+ res = (t->t_cmdbyte & KC8_MDISABLE);
+ pckbc_send_cmd(iot, ioh_c, KBC_AUXENABLE);
+ } else {
+ if (pckbc_send_cmd(iot, ioh_c, KBC_AUXENABLE)
+ && pckbc_get8042cmd(t))
+ res = (~t->t_cmdbyte & KC8_MDISABLE);
+ pckbc_send_cmd(iot, ioh_c, KBC_AUXDISABLE);
+ }
+ if (res == -1)
+ printf("kbc: auxcheck: error\n");
+ else
+ printf("kbc: auxcheck: %d\n", (res > 0));
+ pckbc_get8042cmd(t);
+ return (res > 0);
+}
+
void
pckbc_attach(struct pckbc_softc *sc, int flags)
{
@@ -410,13 +436,17 @@ pckbc_attach(struct pckbc_softc *sc, int
*/
DPRINTF("kbc: aux echo: %x\n", res);
t->t_haveaux = 1;
- if (pckbc_attach_slot(sc, PCKBC_AUX_SLOT, 0))
- cmdbits |= KC8_MENABLE;
}
#ifdef PCKBCDEBUG
else
printf("kbc: aux echo test failed\n");
#endif
+
+ if (res == -1)
+ t->t_haveaux = pckbc_auxcheck(t);
+
+ if (t->t_haveaux && pckbc_attach_slot(sc, PCKBC_AUX_SLOT, 0))
+ cmdbits |= KC8_MENABLE;
#if defined(__i386__) || defined(__amd64__)
if (haskbd == 0 && !ISSET(flags, PCKBCF_FORCE_KEYBOARD_PRESENT)) {
