ACPI / EC: Enhance boot EC sanity check

It's reported that some buggy BIOS tables can contain 2 DSDT ECs, one of
them is invalid but acpi_ec_dsdt_probe() fails to pick the valid one.
This patch simply enhances sanity checks in ec_parse_device() as a
workaround to skip probing wrong namespace ECs.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=195651
Tested-by: Daniel Drake <drake@endlessm.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index f3ff591..b4fd026 100644 (file)
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -1363,6 +1363,8 @@ ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
                                     ec_parse_io_ports, ec);
        if (ACPI_FAILURE(status))
                return status;
+       if (ec->data_addr == 0 || ec->command_addr == 0)
+               return AE_OK;
 
        /* Get GPE bit assignment (EC events). */
        /* TODO: Add support for _GPE returning a package */