ACPI / ACPICA: Fix low-level GPE manipulation code
authorRafael J. Wysocki <rjw@sisk.pl>
Tue, 8 Jun 2010 08:49:08 +0000 (10:49 +0200)
committerLen Brown <len.brown@intel.com>
Sat, 12 Jun 2010 04:44:37 +0000 (00:44 -0400)
ACPICA uses acpi_ev_enable_gpe() for enabling GPEs at the low level,
which is incorrect, because this function only enables the GPE if the
corresponding bit in its enable register's enable_for_run mask is set.
This causes acpi_set_gpe() to work incorrectly if used for enabling
GPEs that were not previously enabled with acpi_enable_gpe().  As a
result, among other things, wakeup-only GPEs are never enabled by
acpi_enable_wakeup_device(), so the devices that use them are unable
to wake up the system.

To fix this issue remove acpi_ev_enable_gpe() and its counterpart
acpi_ev_disable_gpe() and replace acpi_hw_low_disable_gpe() with
acpi_hw_low_set_gpe() that will be used instead to manipulate GPE
enable bits at the low level.  Make the users of acpi_ev_enable_gpe()
and acpi_ev_disable_gpe() call acpi_hw_low_set_gpe() instead and
make sure that GPE enable masks are only updated by acpi_enable_gpe()
and acpi_disable_gpe() when GPE reference counters change from 0
to 1 and from 1 to 0, respectively.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>
drivers/acpi/acpica/acevents.h
drivers/acpi/acpica/achware.h
drivers/acpi/acpica/evgpe.c
drivers/acpi/acpica/evxfevnt.c
drivers/acpi/acpica/hwgpe.c
include/acpi/actypes.h

index 5e094a28cf54a27a072a9e7fca4fcb75d3063346..138bbb52193011be9b66dd46fa920df612c4a5f2 100644 (file)
@@ -78,10 +78,6 @@ acpi_ev_queue_notify_request(struct acpi_namespace_node *node,
 acpi_status
 acpi_ev_update_gpe_enable_masks(struct acpi_gpe_event_info *gpe_event_info);
 
-acpi_status acpi_ev_enable_gpe(struct acpi_gpe_event_info *gpe_event_info);
-
-acpi_status acpi_ev_disable_gpe(struct acpi_gpe_event_info *gpe_event_info);
-
 struct acpi_gpe_event_info *acpi_ev_get_gpe_event_info(acpi_handle gpe_device,
                                                       u32 gpe_number);
 
index c46277d179f006fef3208db917f8cfdec375eeb7..32391588e163c5cb650deaf6c302a97b2efae1fd 100644 (file)
@@ -93,7 +93,8 @@ acpi_status acpi_hw_write_port(acpi_io_address address, u32 value, u32 width);
 u32 acpi_hw_gpe_register_bit(struct acpi_gpe_event_info *gpe_event_info,
                             struct acpi_gpe_register_info *gpe_register_info);
 
-acpi_status acpi_hw_low_disable_gpe(struct acpi_gpe_event_info *gpe_event_info);
+acpi_status
+acpi_hw_low_set_gpe(struct acpi_gpe_event_info *gpe_event_info, u8 action);
 
 acpi_status
 acpi_hw_write_gpe_enable_reg(struct acpi_gpe_event_info *gpe_event_info);
index 57eeb3bde41ea861a8d0cd196f1155bb329276d3..66cd03835d6e79d07be4ff47d27c85ae9c3ecf30 100644 (file)
@@ -99,106 +99,6 @@ acpi_ev_update_gpe_enable_masks(struct acpi_gpe_event_info *gpe_event_info)
        return_ACPI_STATUS(AE_OK);
 }
 
-/*******************************************************************************
- *
- * FUNCTION:    acpi_ev_enable_gpe
- *
- * PARAMETERS:  gpe_event_info          - GPE to enable
- *
- * RETURN:      Status
- *
- * DESCRIPTION: Hardware-enable a GPE. Always enables the GPE, regardless
- *              of type or number of references.
- *
- * Note: The GPE lock should be already acquired when this function is called.
- *
- ******************************************************************************/
-
-acpi_status acpi_ev_enable_gpe(struct acpi_gpe_event_info *gpe_event_info)
-{
-       acpi_status status;
-
-
-       ACPI_FUNCTION_TRACE(ev_enable_gpe);
-
-
-       /*
-        * We will only allow a GPE to be enabled if it has either an
-        * associated method (_Lxx/_Exx) or a handler. Otherwise, the
-        * GPE will be immediately disabled by acpi_ev_gpe_dispatch the
-        * first time it fires.
-        */
-       if (!(gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK)) {
-               return_ACPI_STATUS(AE_NO_HANDLER);
-       }
-
-       /* Ensure the HW enable masks are current */
-
-       status = acpi_ev_update_gpe_enable_masks(gpe_event_info);
-       if (ACPI_FAILURE(status)) {
-               return_ACPI_STATUS(status);
-       }
-
-       /* Clear the GPE (of stale events) */
-
-       status = acpi_hw_clear_gpe(gpe_event_info);
-       if (ACPI_FAILURE(status)) {
-               return_ACPI_STATUS(status);
-       }
-
-       /* Enable the requested GPE */
-
-       status = acpi_hw_write_gpe_enable_reg(gpe_event_info);
-       return_ACPI_STATUS(status);
-}
-
-/*******************************************************************************
- *
- * FUNCTION:    acpi_ev_disable_gpe
- *
- * PARAMETERS:  gpe_event_info          - GPE to disable
- *
- * RETURN:      Status
- *
- * DESCRIPTION: Hardware-disable a GPE. Always disables the requested GPE,
- *              regardless of the type or number of references.
- *
- * Note: The GPE lock should be already acquired when this function is called.
- *
- ******************************************************************************/
-
-acpi_status acpi_ev_disable_gpe(struct acpi_gpe_event_info *gpe_event_info)
-{
-       acpi_status status;
-
-       ACPI_FUNCTION_TRACE(ev_disable_gpe);
-
-
-       /*
-        * Note: Always disable the GPE, even if we think that that it is already
-        * disabled. It is possible that the AML or some other code has enabled
-        * the GPE behind our back.
-        */
-
-       /* Ensure the HW enable masks are current */
-
-       status = acpi_ev_update_gpe_enable_masks(gpe_event_info);
-       if (ACPI_FAILURE(status)) {
-               return_ACPI_STATUS(status);
-       }
-
-       /*
-        * Always H/W disable this GPE, even if we don't know the GPE type.
-        * Simply clear the enable bit for this particular GPE, but do not
-        * write out the current GPE enable mask since this may inadvertently
-        * enable GPEs too early. An example is a rogue GPE that has arrived
-        * during ACPICA initialization - possibly because AML or other code
-        * has enabled the GPE.
-        */
-       status = acpi_hw_low_disable_gpe(gpe_event_info);
-       return_ACPI_STATUS(status);
-}
-
 
 /*******************************************************************************
  *
@@ -450,10 +350,6 @@ static void ACPI_SYSTEM_XFACE acpi_ev_asynch_execute_gpe_method(void *context)
                return_VOID;
        }
 
-       /* Update the GPE register masks for return to enabled state */
-
-       (void)acpi_ev_update_gpe_enable_masks(gpe_event_info);
-
        /*
         * Take a snapshot of the GPE info for this level - we copy the info to
         * prevent a race condition with remove_handler/remove_block.
@@ -606,7 +502,7 @@ acpi_ev_gpe_dispatch(struct acpi_gpe_event_info *gpe_event_info, u32 gpe_number)
                 * Disable the GPE, so it doesn't keep firing before the method has a
                 * chance to run (it runs asynchronously with interrupts enabled).
                 */
-               status = acpi_ev_disable_gpe(gpe_event_info);
+               status = acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_DISABLE);
                if (ACPI_FAILURE(status)) {
                        ACPI_EXCEPTION((AE_INFO, status,
                                        "Unable to disable GPE[0x%2X]",
@@ -643,7 +539,7 @@ acpi_ev_gpe_dispatch(struct acpi_gpe_event_info *gpe_event_info, u32 gpe_number)
                 * Disable the GPE. The GPE will remain disabled a handler
                 * is installed or ACPICA is restarted.
                 */
-               status = acpi_ev_disable_gpe(gpe_event_info);
+               status = acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_DISABLE);
                if (ACPI_FAILURE(status)) {
                        ACPI_EXCEPTION((AE_INFO, status,
                                        "Unable to disable GPE[0x%2X]",
index 7c7bbb4d402ca31a7dcbfe766e5ed2a0eb0e47b3..e3d9f5c8e53d92b5147afeccf8c764879c2ac6d2 100644 (file)
@@ -199,6 +199,44 @@ acpi_status acpi_enable_event(u32 event, u32 flags)
 
 ACPI_EXPORT_SYMBOL(acpi_enable_event)
 
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_clear_and_enable_gpe
+ *
+ * PARAMETERS:  gpe_event_info  - GPE to enable
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Clear the given GPE from stale events and enable it.
+ *
+ ******************************************************************************/
+static acpi_status
+acpi_clear_and_enable_gpe(struct acpi_gpe_event_info *gpe_event_info)
+{
+       acpi_status status;
+
+       /*
+        * We will only allow a GPE to be enabled if it has either an
+        * associated method (_Lxx/_Exx) or a handler. Otherwise, the
+        * GPE will be immediately disabled by acpi_ev_gpe_dispatch the
+        * first time it fires.
+        */
+       if (!(gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK)) {
+               return_ACPI_STATUS(AE_NO_HANDLER);
+       }
+
+       /* Clear the GPE (of stale events) */
+       status = acpi_hw_clear_gpe(gpe_event_info);
+       if (ACPI_FAILURE(status)) {
+               return_ACPI_STATUS(status);
+       }
+
+       /* Enable the requested GPE */
+       status = acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_ENABLE);
+
+       return_ACPI_STATUS(status);
+}
+
 /*******************************************************************************
  *
  * FUNCTION:    acpi_set_gpe
@@ -240,11 +278,11 @@ acpi_status acpi_set_gpe(acpi_handle gpe_device, u32 gpe_number, u8 action)
 
        switch (action) {
        case ACPI_GPE_ENABLE:
-               status = acpi_ev_enable_gpe(gpe_event_info);
+               status = acpi_clear_and_enable_gpe(gpe_event_info);
                break;
 
        case ACPI_GPE_DISABLE:
-               status = acpi_ev_disable_gpe(gpe_event_info);
+               status = acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_DISABLE);
                break;
 
        default:
@@ -307,7 +345,11 @@ acpi_status acpi_enable_gpe(acpi_handle gpe_device, u32 gpe_number, u8 gpe_type)
 
                gpe_event_info->runtime_count++;
                if (gpe_event_info->runtime_count == 1) {
-                       status = acpi_ev_enable_gpe(gpe_event_info);
+                       status = acpi_ev_update_gpe_enable_masks(gpe_event_info);
+                       if (ACPI_SUCCESS(status)) {
+                               status = acpi_clear_and_enable_gpe(gpe_event_info);
+                       }
+
                        if (ACPI_FAILURE(status)) {
                                gpe_event_info->runtime_count--;
                                goto unlock_and_exit;
@@ -334,7 +376,7 @@ acpi_status acpi_enable_gpe(acpi_handle gpe_device, u32 gpe_number, u8 gpe_type)
                 */
                gpe_event_info->wakeup_count++;
                if (gpe_event_info->wakeup_count == 1) {
-                       (void)acpi_ev_update_gpe_enable_masks(gpe_event_info);
+                       status = acpi_ev_update_gpe_enable_masks(gpe_event_info);
                }
        }
 
@@ -394,7 +436,12 @@ acpi_status acpi_disable_gpe(acpi_handle gpe_device, u32 gpe_number, u8 gpe_type
 
                gpe_event_info->runtime_count--;
                if (!gpe_event_info->runtime_count) {
-                       status = acpi_ev_disable_gpe(gpe_event_info);
+                       status = acpi_ev_update_gpe_enable_masks(gpe_event_info);
+                       if (ACPI_SUCCESS(status)) {
+                               status = acpi_hw_low_set_gpe(gpe_event_info,
+                                                            ACPI_GPE_DISABLE);
+                       }
+
                        if (ACPI_FAILURE(status)) {
                                gpe_event_info->runtime_count++;
                                goto unlock_and_exit;
@@ -415,7 +462,7 @@ acpi_status acpi_disable_gpe(acpi_handle gpe_device, u32 gpe_number, u8 gpe_type
 
                gpe_event_info->wakeup_count--;
                if (!gpe_event_info->wakeup_count) {
-                       (void)acpi_ev_update_gpe_enable_masks(gpe_event_info);
+                       status = acpi_ev_update_gpe_enable_masks(gpe_event_info);
                }
        }
 
index d989b8e786cc9839417998e545776df1c769c8e8..40388e23e103963b0eb1d56dcb2f7e305ea640d2 100644 (file)
@@ -78,23 +78,27 @@ u32 acpi_hw_gpe_register_bit(struct acpi_gpe_event_info *gpe_event_info,
 
 /******************************************************************************
  *
- * FUNCTION:   acpi_hw_low_disable_gpe
+ * FUNCTION:   acpi_hw_low_set_gpe
  *
  * PARAMETERS: gpe_event_info      - Info block for the GPE to be disabled
+ *             action              - Enable or disable
  *
  * RETURN:     Status
  *
- * DESCRIPTION: Disable a single GPE in the enable register.
+ * DESCRIPTION: Enable or disable a single GPE in its enable register.
  *
  ******************************************************************************/
 
-acpi_status acpi_hw_low_disable_gpe(struct acpi_gpe_event_info *gpe_event_info)
+acpi_status
+acpi_hw_low_set_gpe(struct acpi_gpe_event_info *gpe_event_info, u8 action)
 {
        struct acpi_gpe_register_info *gpe_register_info;
        acpi_status status;
        u32 enable_mask;
        u32 register_bit;
 
+       ACPI_FUNCTION_ENTRY();
+
        /* Get the info block for the entire GPE register */
 
        gpe_register_info = gpe_event_info->register_info;
@@ -109,11 +113,23 @@ acpi_status acpi_hw_low_disable_gpe(struct acpi_gpe_event_info *gpe_event_info)
                return (status);
        }
 
-       /* Clear just the bit that corresponds to this GPE */
+       /* Set ot clear just the bit that corresponds to this GPE */
 
        register_bit = acpi_hw_gpe_register_bit(gpe_event_info,
                                                gpe_register_info);
-       ACPI_CLEAR_BIT(enable_mask, register_bit);
+       switch (action) {
+       case ACPI_GPE_ENABLE:
+               ACPI_SET_BIT(enable_mask, register_bit);
+               break;
+
+       case ACPI_GPE_DISABLE:
+               ACPI_CLEAR_BIT(enable_mask, register_bit);
+               break;
+
+       default:
+               ACPI_ERROR((AE_INFO, "Invalid action\n"));
+               return (AE_BAD_PARAMETER);
+       }
 
        /* Write the updated enable mask */
 
index de5e99a995307f8e933adfaa8d826b7580b40d64..6881f5b7b7bea31d817aa66c66b76070a03d7d64 100644 (file)
@@ -663,7 +663,7 @@ typedef u32 acpi_event_status;
 #define ACPI_GPE_MAX                    0xFF
 #define ACPI_NUM_GPE                    256
 
-/* Actions for acpi_set_gpe */
+/* Actions for acpi_set_gpe and acpi_hw_low_set_gpe */
 
 #define ACPI_GPE_ENABLE                 0
 #define ACPI_GPE_DISABLE                1