[PATCH v3 15/17] ACPI: add acpi_bus_get_status_handle()

Bjorn Helgaas
2009-09-21T19:29:58Z

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>
---
drivers/acpi/bus.c | 49 +++++++++++++++++++++--------------------------
include/acpi/acpi_bus.h | 2 ++
2 files changed, 24 insertions(+), 27 deletions(-)

diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c
index 135fbfe..7411915 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,
diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
index ef1cb23..13a63a6 100644
--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h
@@ -322,6 +322,8 @@ extern void unregister_acpi_bus_notifier(struct notifier_block *nb);

int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device);
void acpi_bus_data_handler(acpi_handle handle, void *context);
+acpi_status acpi_bus_get_status_handle(acpi_handle handle,
+ unsigned long long *sta);
int acpi_bus_get_status(struct acpi_device *device);
int acpi_bus_get_power(acpi_handle handle, int *state);
int acpi_bus_set_power(acpi_handle handle, int state);