[PATCH 3/3] toshiba_acpi: Refuse to load on machines with buggy INFO implementations

From: Seth Forshee
Date: Mon Mar 05 2012 - 22:30:43 EST


Several Satellite models have a buggy implementation of the INFO method
that causes ACPI exceptions when executed:

ACPI Error: Result stack is empty! State=ffff88012d70f800 (20110413/dswstate-98)
ACPI Exception: AE_AML_NO_RETURN_VALUE, Missing or null operand (20110413/dsutils-646)
ACPI Exception: AE_AML_NO_RETURN_VALUE, While creating Arg 0 (20110413/dsutils-763)
ACPI Error: Method parse/execution failed [\_SB_.VALZ.GETE] (Node ffff880131175eb0), AE_AML_NO_RETURN_VALUE (20110413/psparse-536)
ACPI Error: Method parse/execution failed [\_SB_.VALZ.INFO] (Node ffff880131175ed8), AE_AML_NO_RETURN_VALUE (20110413/psparse-536)
toshiba_acpi: ACPI INFO method execution failed
toshiba_acpi: Failed to query hotkey event

All known machines with this implementation also have a WMI interface
with event GUID 59142400-C6A3-40FA-BADB-8A2652834100 which is not seen
on any other models. Refuse to load toshiba_acpi on machines with this
guid.

Signed-off-by: Seth Forshee <seth.forshee@xxxxxxxxxxxxx>
---
drivers/platform/x86/Kconfig | 1 +
drivers/platform/x86/Makefile | 4 ++++
drivers/platform/x86/toshiba_acpi.c | 10 ++++++++++
3 files changed, 15 insertions(+), 0 deletions(-)

diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
index f995e6e..b420389f 100644
--- a/drivers/platform/x86/Kconfig
+++ b/drivers/platform/x86/Kconfig
@@ -580,6 +580,7 @@ config TOPSTAR_LAPTOP
config ACPI_TOSHIBA
tristate "Toshiba Laptop Extras"
depends on ACPI
+ depends on ACPI_WMI
select LEDS_CLASS
select NEW_LEDS
depends on BACKLIGHT_CLASS_DEVICE
diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile
index 293a320..95ce3a1 100644
--- a/drivers/platform/x86/Makefile
+++ b/drivers/platform/x86/Makefile
@@ -29,7 +29,11 @@ obj-$(CONFIG_ACPI_WMI) += wmi.o
obj-$(CONFIG_MSI_WMI) += msi-wmi.o
obj-$(CONFIG_ACPI_ASUS) += asus_acpi.o
obj-$(CONFIG_TOPSTAR_LAPTOP) += topstar-laptop.o
+
+# toshiba_acpi must link after wmi to ensure that wmi devices are found
+# before toshiba_acpi initializes
obj-$(CONFIG_ACPI_TOSHIBA) += toshiba_acpi.o
+
obj-$(CONFIG_TOSHIBA_BT_RFKILL) += toshiba_bluetooth.o
obj-$(CONFIG_INTEL_SCU_IPC) += intel_scu_ipc.o
obj-$(CONFIG_INTEL_SCU_IPC_UTIL) += intel_scu_ipcutil.o
diff --git a/drivers/platform/x86/toshiba_acpi.c b/drivers/platform/x86/toshiba_acpi.c
index 621b207..b6d0566 100644
--- a/drivers/platform/x86/toshiba_acpi.c
+++ b/drivers/platform/x86/toshiba_acpi.c
@@ -63,6 +63,8 @@ MODULE_AUTHOR("John Belmonte");
MODULE_DESCRIPTION("Toshiba Laptop ACPI Extras Driver");
MODULE_LICENSE("GPL");

+#define TOSHIBA_WMI_EVENT_GUID "59142400-C6A3-40FA-BADB-8A2652834100"
+
/* Scan code for Fn key on TOS1900 models */
#define TOS1900_FN_SCAN 0x6e

@@ -1263,6 +1265,14 @@ static int __init toshiba_acpi_init(void)
{
int ret;

+ /*
+ * Machines with this WMI guid aren't supported due to bugs in
+ * their AML. This check relies on wmi initializing before
+ * toshiba_acpi to guarantee guids have been identified.
+ */
+ if (wmi_has_guid(TOSHIBA_WMI_EVENT_GUID))
+ return -ENODEV;
+
toshiba_proc_dir = proc_mkdir(PROC_TOSHIBA, acpi_root_dir);
if (!toshiba_proc_dir) {
pr_err("Unable to create proc dir " PROC_TOSHIBA "\n");
--
1.7.9

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/