4 files changed, 12 insertions, 0 deletions

diff --git a/drivers/pnp/core.c b/drivers/pnp/core.c
index d8d75541552c..3e20b1cc7778 100644
--- a/drivers/pnp/core.c
+++ b/drivers/pnp/core.c
@@ -23,6 +23,14 @@ static LIST_HEAD(pnp_protocols);
 LIST_HEAD(pnp_global);
 DEFINE_SPINLOCK(pnp_lock);
 
+/*
+ * ACPI or PNPBIOS should tell us about all platform devices, so we can
+ * skip some blind probes.  ISAPNP typically enumerates only plug-in ISA
+ * devices, not built-in things like COM ports.
+ */
+int pnp_platform_devices;
+EXPORT_SYMBOL(pnp_platform_devices);
+
 void *pnp_alloc(long size)
 {
         void *result;
diff --git a/drivers/pnp/pnpacpi/core.c b/drivers/pnp/pnpacpi/core.c
index 7eb8275185b6..a00548799e98 100644
--- a/drivers/pnp/pnpacpi/core.c
+++ b/drivers/pnp/pnpacpi/core.c
@@ -285,6 +285,7 @@ static int __init pnpacpi_init(void)
         acpi_get_devices(NULL, pnpacpi_add_device_handler, NULL, NULL);
         pnp_info("PnP ACPI: found %d devices", num);
         unregister_acpi_bus_type(&acpi_pnp_bus);
+        pnp_platform_devices = 1;
         return 0;
 }
 subsys_initcall(pnpacpi_init);
diff --git a/drivers/pnp/pnpbios/core.c b/drivers/pnp/pnpbios/core.c
index b71aff21b3fc..3a201b77b963 100644
--- a/drivers/pnp/pnpbios/core.c
+++ b/drivers/pnp/pnpbios/core.c
@@ -570,6 +570,7 @@ static int __init pnpbios_init(void)
         /* scan for pnpbios devices */
         build_devlist();
 
+        pnp_platform_devices = 1;
         return 0;
 }
 
diff --git a/include/linux/pnp.h b/include/linux/pnp.h
index 00dae5ba128a..2a1897e6f937 100644
--- a/include/linux/pnp.h
+++ b/include/linux/pnp.h
@@ -364,6 +364,7 @@ int pnp_add_device(struct pnp_dev *dev);
 int pnp_device_attach(struct pnp_dev *pnp_dev);
 void pnp_device_detach(struct pnp_dev *pnp_dev);
 extern struct list_head pnp_global;
+extern int pnp_platform_devices;
 
 /* multidevice card support */
 int pnp_add_card(struct pnp_card *card);
@@ -411,6 +412,7 @@ static inline int pnp_init_device(struct pnp_dev *dev) { return -ENODEV; }
 static inline int pnp_add_device(struct pnp_dev *dev) { return -ENODEV; }
 static inline int pnp_device_attach(struct pnp_dev *pnp_dev) { return -ENODEV; }
 static inline void pnp_device_detach(struct pnp_dev *pnp_dev) { ; }
+#define pnp_platform_devices 0
 
 /* multidevice card support */
 static inline int pnp_add_card(struct pnp_card *card) { return -ENODEV; }