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authorBjorn Helgaas <bjorn.helgaas@hp.com>2009-09-21 19:30:01 +0000
committerLen Brown <len.brown@intel.com>2009-09-25 14:24:30 -0400
commit402ac53614bce0c273c73a80339556bf56dd3d39 (patch)
treeee08b782ad49532e52712c077333ee88a042019c /drivers/acpi/bus.c
parent51a85faf2d4ffecd8384b3f501f9f7ee2b05ee53 (diff)
downloadlwn-402ac53614bce0c273c73a80339556bf56dd3d39.tar.gz
lwn-402ac53614bce0c273c73a80339556bf56dd3d39.zip
ACPI: add acpi_bus_get_status_handle()
Add acpi_bus_get_status_handle() so we can get the status of a namespace object before building a struct acpi_device. This removes a use of "device->flags.dynamic_status", a cached indicator of whether _STA exists. It seems simpler and more reliable to just evaluate _STA and catch AE_NOT_FOUND errors. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Len Brown <len.brown@intel.com>
Diffstat (limited to 'drivers/acpi/bus.c')
-rw-r--r--drivers/acpi/bus.c49
1 files changed, 22 insertions, 27 deletions
diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c
index 135fbfe1825c..741191524353 100644
--- a/drivers/acpi/bus.c
+++ b/drivers/acpi/bus.c
@@ -94,36 +94,33 @@ int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
EXPORT_SYMBOL(acpi_bus_get_device);
-int acpi_bus_get_status(struct acpi_device *device)
+acpi_status acpi_bus_get_status_handle(acpi_handle handle,
+ unsigned long long *sta)
{
- acpi_status status = AE_OK;
- unsigned long long sta = 0;
-
+ acpi_status status;
- if (!device)
- return -EINVAL;
+ status = acpi_evaluate_integer(handle, "_STA", NULL, sta);
+ if (ACPI_SUCCESS(status))
+ return AE_OK;
- /*
- * Evaluate _STA if present.
- */
- if (device->flags.dynamic_status) {
- status =
- acpi_evaluate_integer(device->handle, "_STA", NULL, &sta);
- if (ACPI_FAILURE(status))
- return -ENODEV;
- STRUCT_TO_INT(device->status) = (int)sta;
+ if (status == AE_NOT_FOUND) {
+ *sta = ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED |
+ ACPI_STA_DEVICE_UI | ACPI_STA_DEVICE_FUNCTIONING;
+ return AE_OK;
}
+ return status;
+}
- /*
- * According to ACPI spec some device can be present and functional
- * even if the parent is not present but functional.
- * In such conditions the child device should not inherit the status
- * from the parent.
- */
- else
- STRUCT_TO_INT(device->status) =
- ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED |
- ACPI_STA_DEVICE_UI | ACPI_STA_DEVICE_FUNCTIONING;
+int acpi_bus_get_status(struct acpi_device *device)
+{
+ acpi_status status;
+ unsigned long long sta;
+
+ status = acpi_bus_get_status_handle(device->handle, &sta);
+ if (ACPI_FAILURE(status))
+ return -ENODEV;
+
+ STRUCT_TO_INT(device->status) = (int) sta;
if (device->status.functional && !device->status.present) {
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] status [%08x]: "
@@ -135,10 +132,8 @@ int acpi_bus_get_status(struct acpi_device *device)
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] status [%08x]\n",
device->pnp.bus_id,
(u32) STRUCT_TO_INT(device->status)));
-
return 0;
}
-
EXPORT_SYMBOL(acpi_bus_get_status);
void acpi_bus_private_data_handler(acpi_handle handle,