ACPICA: Events: Cleanup GPE dispatcher type obtaining code

ACPICA commit 7926d5ca9452c87f866938dcea8f12e1efb58f89

There is an issue in acpi_install_gpe_handler() and acpi_remove_gpe_handler().
The code to obtain the GPE dispatcher type from the Handler->original_flags
is wrong:
    if (((Handler->original_flags & ACPI_GPE_DISPATCH_METHOD) ||
         (Handler->original_flags & ACPI_GPE_DISPATCH_NOTIFY)) &&
ACPI_GPE_DISPATCH_NOTIFY is 0x03 and ACPI_GPE_DISPATCH_METHOD is 0x02, thus
this statement is TRUE for the following dispatcher types:
    0x01 (ACPI_GPE_DISPATCH_HANDLER): not expected
    0x02 (ACPI_GPE_DISPATCH_METHOD): expected
    0x03 (ACPI_GPE_DISPATCH_NOTIFY): expected

There is no functional issue due to this because Handler->original_flags is
only set in acpi_install_gpe_handler(), and an earlier checker has excluded
the ACPI_GPE_DISPATCH_HANDLER:
    if ((gpe_event_info->Flags & ACPI_GPE_DISPATCH_MASK) ==
            ACPI_GPE_DISPATCH_HANDLER)
    {
        Status = AE_ALREADY_EXISTS;
        goto free_and_exit;
    }
    ...
    Handler->original_flags = (u8) (gpe_event_info->Flags &
        (ACPI_GPE_XRUPT_TYPE_MASK | ACPI_GPE_DISPATCH_MASK));

We need to clean this up before modifying the GPE dispatcher type values.

In order to prevent such issue from happening in the future, this patch
introduces ACPI_GPE_DISPATCH_TYPE() macro to be used to obtain the GPE
dispatcher types. Lv Zheng.

Link: https://github.com/acpica/acpica/commit/7926d5ca
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: David E. Box <david.e.box@linux.intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 3 insertions, 5 deletions

diff --git a/drivers/acpi/acpica/evgpeutil.c b/drivers/acpi/acpica/evgpeutil.c
index 3f1c5aa682a5..b1978122f6a9 100644
--- a/drivers/acpi/acpica/evgpeutil.c
+++ b/drivers/acpi/acpica/evgpeutil.c
@@ -324,7 +324,7 @@ acpi_ev_delete_gpe_handlers(struct acpi_gpe_xrupt_info *gpe_xrupt_info,
                                                                  ACPI_GPE_REGISTER_WIDTH)
                                                                 + j];
 
-                        if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) ==
+                        if (ACPI_GPE_DISPATCH_TYPE(gpe_event_info->flags) ==
                             ACPI_GPE_DISPATCH_HANDLER) {
 
                                 /* Delete an installed handler block */
@@ -333,10 +333,8 @@ acpi_ev_delete_gpe_handlers(struct acpi_gpe_xrupt_info *gpe_xrupt_info,
                                 gpe_event_info->dispatch.handler = NULL;
                                 gpe_event_info->flags &=
                                     ~ACPI_GPE_DISPATCH_MASK;
-                        } else
-                            if ((gpe_event_info->
-                                 flags & ACPI_GPE_DISPATCH_MASK) ==
-                                ACPI_GPE_DISPATCH_NOTIFY) {
+                        } else if (ACPI_GPE_DISPATCH_TYPE(gpe_event_info->flags)
+                                   == ACPI_GPE_DISPATCH_NOTIFY) {
 
                                 /* Delete the implicit notification device list */