ACPI/PCI: Change pci_osc_control_set() to query control bits first

Current pci_osc_control_set() evaluates _OSC without query for control
bits, unless __pci_osc_support_set() is called beforehand. But as
strongly recommended in PCI firmware specification, it should query
control bits first.

This patch changes pci_osc_control_set() to query control bits first
even if __pci_osc_support_set() is not called beforehand.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

1 files changed, 31 insertions, 16 deletions

diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c
index 14848bf95e82..7d33fc0ec2fc 100644
--- a/drivers/pci/pci-acpi.c
+++ b/drivers/pci/pci-acpi.c
@@ -120,14 +120,35 @@ out_kfree:
         return status;
 }
 
+static acpi_status __acpi_query_osc(u32 flags, struct acpi_osc_data *osc_data)
+{
+        acpi_status status;
+        u32 support_set;
+        struct acpi_osc_args osc_args;
+
+        /* do _OSC query for all possible controls */
+        support_set = osc_data->support_set | (flags & OSC_SUPPORT_MASKS);
+        osc_args.capbuf[OSC_QUERY_TYPE] = OSC_QUERY_ENABLE;
+        osc_args.capbuf[OSC_SUPPORT_TYPE] = support_set;
+        osc_args.capbuf[OSC_CONTROL_TYPE] = OSC_CONTROL_MASKS;
+
+        status = acpi_run_osc(osc_data->handle, &osc_args);
+        if (ACPI_SUCCESS(status)) {
+                osc_data->support_set = support_set;
+                osc_data->query_result = osc_args.query_result;
+                osc_data->is_queried = 1;
+        }
+
+        return status;
+}
+
 static acpi_status acpi_query_osc(acpi_handle handle,
                                   u32 level, void *context, void **retval)
 {
         acpi_status status;
         struct acpi_osc_data *osc_data;
-        u32 flags = (unsigned long)context, support_set;
+        u32 flags = (unsigned long)context;
         acpi_handle tmp;
-        struct acpi_osc_args osc_args;
 
         status = acpi_get_handle(handle, "_OSC", &tmp);
         if (ACPI_FAILURE(status))
@@ -141,18 +162,7 @@ static acpi_status acpi_query_osc(acpi_handle handle,
                 goto out;
         }
 
-        /* do _OSC query for all possible controls */
-        support_set = osc_data->support_set | (flags & OSC_SUPPORT_MASKS);
-        osc_args.capbuf[OSC_QUERY_TYPE] = OSC_QUERY_ENABLE;
-        osc_args.capbuf[OSC_SUPPORT_TYPE] = support_set;
-        osc_args.capbuf[OSC_CONTROL_TYPE] = OSC_CONTROL_MASKS;
-
-        status = acpi_run_osc(handle, &osc_args);
-        if (ACPI_SUCCESS(status)) {
-                osc_data->support_set = support_set;
-                osc_data->query_result = osc_args.query_result;
-                osc_data->is_queried = 1;
-        }
+        status = __acpi_query_osc(flags, osc_data);
 out:
         mutex_unlock(&pci_acpi_lock);
         return status;
@@ -209,8 +219,13 @@ acpi_status pci_osc_control_set(acpi_handle handle, u32 flags)
                 goto out;
         }
 
-        if (osc_data->is_queried &&
-            ((osc_data->query_result & ctrlset) != ctrlset)) {
+        if (!osc_data->is_queried) {
+                status = __acpi_query_osc(osc_data->support_set, osc_data);
+                if (ACPI_FAILURE(status))
+                        goto out;
+        }
+
+        if ((osc_data->query_result & ctrlset) != ctrlset) {
                 status = AE_SUPPORT;
                 goto out;
         }