pnp: Implement common handling for PnP config modes

Many super i/o chips only answer to PnP requests if they are in a
configuration state (sometimes also called ext func mode). To cope with
that, the code of many chips implements its own version of our default
PnP functions like pnp_set_resource(), pnp_enable_resource() etc.

To avoid this code duplication, this patch extends our PnP device
interface with optional functions to enter and exit configuration mode.

Change-Id: I9b7662a0db70ede93276764fa15020f251eb46bd
Signed-off-by: Nico Huber <nico.h@gmx.de>
Reviewed-on: http://review.coreboot.org/3481
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>

src/device/pnp_device.c

@@ -6,6 +6,7 @@
  * Copyright (C) 2004 Li-Ta Lo <ollie@lanl.gov>
  * Copyright (C) 2005 Tyan
  * (Written by Yinghai Lu <yhlu@tyan.com> for Tyan)
+ * Copyright (C) 2013 Nico Huber <nico.h@gmx.de>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -29,6 +30,20 @@
 #include <device/device.h>
 #include <device/pnp.h>
 
+/* PNP config mode wrappers */
+
+void pnp_enter_conf_mode(device_t dev)
+{
+	if (dev->ops->ops_pnp_mode)
+		dev->ops->ops_pnp_mode->enter_conf_mode(dev);
+}
+
+void pnp_exit_conf_mode(device_t dev)
+{
+	if (dev->ops->ops_pnp_mode)
+		dev->ops->ops_pnp_mode->exit_conf_mode(dev);
+}
+
 /* PNP fundamental operations */
 
 void pnp_write_config(device_t dev, u8 reg, u8 value)
@@ -133,32 +148,42 @@ void pnp_set_resources(device_t dev)
 {
 	struct resource *res;
 
+	pnp_enter_conf_mode(dev);
+
 	/* Select the logical device (LDN). */
 	pnp_set_logical_device(dev);
 
 	/* Paranoia says I should disable the device here... */
 	for (res = dev->resource_list; res; res = res->next)
 		pnp_set_resource(dev, res);
+
+	pnp_exit_conf_mode(dev);
 }
 
 void pnp_enable_resources(device_t dev)
 {
+	pnp_enter_conf_mode(dev);
 	pnp_set_logical_device(dev);
 	pnp_set_enable(dev, 1);
+	pnp_exit_conf_mode(dev);
 }
 
 void pnp_enable(device_t dev)
 {
 	if (!dev->enabled) {
+		pnp_enter_conf_mode(dev);
 		pnp_set_logical_device(dev);
 		pnp_set_enable(dev, 0);
+		pnp_exit_conf_mode(dev);
 	}
 }
 
 void pnp_alt_enable(device_t dev)
 {
+	pnp_enter_conf_mode(dev);
 	pnp_set_logical_device(dev);
 	pnp_set_enable(dev, !!dev->enabled);
+	pnp_exit_conf_mode(dev);
 }
 
 struct device_operations pnp_ops = {

src/include/device/device.h

@@ -13,6 +13,7 @@ typedef struct device * device_t;
 struct pci_operations;
 struct pci_bus_operations;
 struct smbus_bus_operations;
+struct pnp_mode_ops;
 
 /* Chip operations */
 struct chip_operations {
@@ -42,6 +43,7 @@ struct device_operations {
 	const struct pci_operations *ops_pci;
 	const struct smbus_bus_operations *ops_smbus_bus;
 	const struct pci_bus_operations *ops_pci_bus;
+	const struct pnp_mode_ops *ops_pnp_mode;
 };
 #endif
 

src/include/device/pnp.h

@@ -52,5 +52,12 @@ struct resource *pnp_get_resource(device_t dev, unsigned index);
 void pnp_enable_devices(struct device *dev, struct device_operations *ops,
 			unsigned int functions, struct pnp_info *info);
 
+struct pnp_mode_ops {
+	void (*enter_conf_mode)(device_t dev);
+	void (*exit_conf_mode)(device_t dev);
+};
+void pnp_enter_conf_mode(device_t dev);
+void pnp_exit_conf_mode(device_t dev);
+
 #endif
 #endif /* DEVICE_PNP_H */