Disable ACPI burst mode on the 2015 Chromebook Pixel, where it freezes.

Diff from jcs@, ok pirofti@

diff --git a/sys/dev/acpi/acpidev.h b/sys/dev/acpi/acpidev.h
index e359927..077a29e 100644 (file)
--- a/sys/dev/acpi/acpidev.h
+++ b/sys/dev/acpi/acpidev.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: acpidev.h,v 1.42 2017/09/06 13:01:48 jcs Exp $ */
+/* $OpenBSD: acpidev.h,v 1.43 2018/01/17 07:40:29 bentley Exp $ */
 /*
  * Copyright (c) 2005 Marco Peereboom <marco@openbsd.org>
  * Copyright (c) 2005 Thorsten Lockert <tholo@sigmasoft.com>
@@ -374,6 +374,7 @@ struct acpiec_softc {
        struct acpiec_event     sc_events[ACPIEC_MAX_EVENTS];
        int                     sc_gotsci;
        int                     sc_glk;
+       int                     sc_cantburst;
 };
 
 void           acpibtn_disable_psw(void);

diff --git a/sys/dev/acpi/acpiec.c b/sys/dev/acpi/acpiec.c
index c39f302..ecf0f3f 100644 (file)
--- a/sys/dev/acpi/acpiec.c
+++ b/sys/dev/acpi/acpiec.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: acpiec.c,v 1.56 2017/03/11 21:46:32 jcs Exp $ */
+/* $OpenBSD: acpiec.c,v 1.57 2018/01/17 07:40:29 bentley Exp $ */
 /*
  * Copyright (c) 2006 Can Erkin Acar <canacar@openbsd.org>
  *
@@ -77,6 +77,8 @@ void          acpiec_unlock(struct acpiec_softc *);
 
 int    acpiec_reg(struct acpiec_softc *);
 
+extern char    *hw_vendor, *hw_prod;
+
 struct cfattach acpiec_ca = {
        sizeof(struct acpiec_softc), acpiec_match, acpiec_attach
 };
@@ -195,6 +197,9 @@ acpiec_write_1(struct acpiec_softc *sc, u_int8_t addr, u_int8_t data)
 void
 acpiec_burst_enable(struct acpiec_softc *sc)
 {
+       if (sc->sc_cantburst)
+               return;
+
        acpiec_write_cmd(sc, EC_CMD_BE);
        acpiec_read_data(sc);
 }
@@ -202,6 +207,9 @@ acpiec_burst_enable(struct acpiec_softc *sc)
 void
 acpiec_burst_disable(struct acpiec_softc *sc)
 {
+       if (sc->sc_cantburst)
+               return;
+
        if ((acpiec_status(sc) & EC_STAT_BURST) == EC_STAT_BURST)
                acpiec_write_cmd(sc, EC_CMD_BD);
 }
@@ -273,6 +281,7 @@ acpiec_attach(struct device *parent, struct device *self, void *aux)
 
        sc->sc_acpi = (struct acpi_softc *)parent;
        sc->sc_devnode = aa->aaa_node;
+       sc->sc_cantburst = 0;
 
        if (aml_evalinteger(sc->sc_acpi, sc->sc_devnode, "_STA", 0, NULL, &st))
                st = STA_PRESENT | STA_ENABLED | STA_DEV_OK;
@@ -294,6 +303,16 @@ acpiec_attach(struct device *parent, struct device *self, void *aux)
                return;
        }
 
+       /*
+        * Some Chromebooks using the Google EC do not support burst mode and
+        * cause us to spin forever waiting for the acknowledgment.  Don't use
+        * burst mode at all on these machines.
+        */
+       if (hw_vendor != NULL && hw_prod != NULL &&
+           strcmp(hw_vendor, "GOOGLE") == 0 &&
+           strcmp(hw_prod, "Samus") == 0)
+               sc->sc_cantburst = 1;
+
        acpiec_get_events(sc);
 
        dnprintf(10, "%s: GPE: %d\n", DEVNAME(sc), sc->sc_gpe);