PCI hotplug: introduce functions for ACPI slot detection

[linux-2.6-omap-h63xx.git] / drivers / pci / hotplug / acpi_pcihp.c

diff --git a/drivers/pci/hotplug/acpi_pcihp.c b/drivers/pci/hotplug/acpi_pcihp.c
index e17ef54f0efced2d0173a9f5af250c2f0fa93517..c62ab8d240aa42b787d4632605dd1166fc9aebf9 100644 (file)
--- a/drivers/pci/hotplug/acpi_pcihp.c
+++ b/drivers/pci/hotplug/acpi_pcihp.c
@@ -501,5 +501,74 @@ int acpi_root_bridge(acpi_handle handle)
 }
 EXPORT_SYMBOL_GPL(acpi_root_bridge);
 
+
+static int is_ejectable(acpi_handle handle)
+{
+       acpi_status status;
+       acpi_handle tmp;
+       unsigned long long removable;
+       status = acpi_get_handle(handle, "_ADR", &tmp);
+       if (ACPI_FAILURE(status))
+               return 0;
+       status = acpi_get_handle(handle, "_EJ0", &tmp);
+       if (ACPI_SUCCESS(status))
+               return 1;
+       status = acpi_evaluate_integer(handle, "_RMV", NULL, &removable);
+       if (ACPI_SUCCESS(status) && removable)
+               return 1;
+       return 0;
+}
+
+/**
+ * acpi_pcihp_check_ejectable - check if handle is ejectable ACPI PCI slot
+ * @pbus: the PCI bus of the PCI slot corresponding to 'handle'
+ * @handle: ACPI handle to check
+ *
+ * Return 1 if handle is ejectable PCI slot, 0 otherwise.
+ */
+int acpi_pci_check_ejectable(struct pci_bus *pbus, acpi_handle handle)
+{
+       acpi_handle bridge_handle, parent_handle;
+
+       if (!(bridge_handle = acpi_pci_get_bridge_handle(pbus)))
+               return 0;
+       if ((ACPI_FAILURE(acpi_get_parent(handle, &parent_handle))))
+               return 0;
+       if (bridge_handle != parent_handle)
+               return 0;
+       return is_ejectable(handle);
+}
+EXPORT_SYMBOL_GPL(acpi_pci_check_ejectable);
+
+static acpi_status
+check_hotplug(acpi_handle handle, u32 lvl, void *context, void **rv)
+{
+       int *found = (int *)context;
+       if (is_ejectable(handle)) {
+               *found = 1;
+               return AE_CTRL_TERMINATE;
+       }
+       return AE_OK;
+}
+
+/**
+ * acpi_pci_detect_ejectable - check if the PCI bus has ejectable slots
+ * @pbus - PCI bus to scan
+ *
+ * Returns 1 if the PCI bus has ACPI based ejectable slots, 0 otherwise.
+ */
+int acpi_pci_detect_ejectable(struct pci_bus *pbus)
+{
+       acpi_handle handle;
+       int found = 0;
+
+       if (!(handle = acpi_pci_get_bridge_handle(pbus)))
+               return 0;
+       acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, (u32)1,
+                           check_hotplug, (void *)&found, NULL);
+       return found;
+}
+EXPORT_SYMBOL_GPL(acpi_pci_detect_ejectable);
+
 module_param(debug_acpi, bool, 0644);
 MODULE_PARM_DESC(debug_acpi, "Debugging mode for ACPI enabled or not");