PCI Hotplug skeleton driver

diff -Nru a/drivers/hotplug/pcihp_skeleton.c b/drivers/hotplug/pcihp_skeleton.c
@@ -0,0 +1,432 @@
+/*
+ * PCI Hot Plug Controller Skeleton Driver - 0.1
+ *
+ * Copyright (c) 2001 Greg Kroah-Hartman ([email protected])
+ * Copyright (c) 2001 IBM Corp.
+ *
+ * All rights reserved.
+ *
+ * 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
+ * the Free Software Foundation; either version 2 of the License, or (at
+ * your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ * NON INFRINGEMENT.  See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * This driver is to be used as a skeleton driver to be show how to interface
+ * with the pci hotplug core easily.
+ *
+ * Send feedback to <[email protected]>
+ *
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/pci.h>
+#include <linux/init.h>
+#include "pci_hotplug.h"
+
+
+#define SLOT_MAGIC	0x67267322
+struct slot {
+	u32 magic;
+	u8 number;
+	struct hotplug_slot *hotplug_slot;
+	struct list_head slot_list;
+};
+
+static LIST_HEAD(slot_list);
+
+#if !defined(CONFIG_HOTPLUG_PCI_SKELETON_MODULE)
+	#define MY_NAME	"pcihp_skeleton"
+#else
+	#define MY_NAME	THIS_MODULE->name
+#endif
+
+#define dbg(format, arg...)					\
+	do {							\
+		if (debug)					\
+			printk (KERN_DEBUG "%s: " format "\n",	\
+				MY_NAME , ## arg); 		\
+	} while (0)
+#define err(format, arg...) printk(KERN_ERR "%s: " format "\n", MY_NAME , ## arg)
+#define info(format, arg...) printk(KERN_INFO "%s: " format "\n", MY_NAME , ## arg)
+#define warn(format, arg...) printk(KERN_WARNING "%s: " format "\n", MY_NAME , ## arg)
+
+
+
+/* local variables */
+static int debug;
+static int num_slots;
+
+#define DRIVER_VERSION	"0.1"
+#define DRIVER_AUTHOR	"Greg Kroah-Hartman <[email protected]>"
+#define DRIVER_DESC	"Hot Plug PCI Controller Skeleton Driver"
+
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE("GPL");
+MODULE_PARM(debug, "i");
+MODULE_PARM_DESC(debug, "Debugging mode enabled or not");
+
+static int enable_slot		(struct hotplug_slot *slot);
+static int disable_slot		(struct hotplug_slot *slot);
+static int set_attention_status (struct hotplug_slot *slot, u8 value);
+static int hardware_test	(struct hotplug_slot *slot, u32 value);
+static int get_power_status	(struct hotplug_slot *slot, u8 *value);
+static int get_attention_status	(struct hotplug_slot *slot, u8 *value);
+static int get_latch_status	(struct hotplug_slot *slot, u8 *value);
+static int get_adapter_status	(struct hotplug_slot *slot, u8 *value);
+
+static struct hotplug_slot_ops skel_hotplug_slot_ops = {
+	owner:			THIS_MODULE,
+	enable_slot:		enable_slot,
+	disable_slot:		disable_slot,
+	set_attention_status:	set_attention_status,
+	hardware_test:		hardware_test,
+	get_power_status:	get_power_status,
+	get_attention_status:	get_attention_status,
+	get_latch_status:	get_latch_status,
+	get_adapter_status:	get_adapter_status,
+};
+
+
+/* Inline functions to check the sanity of a pointer that is passed to us */
+static inline int slot_paranoia_check (struct slot *slot, const char *function)
+{
+	if (!slot) {
+		dbg("%s - slot == NULL", function);
+		return -1;
+	}
+	if (slot->magic != SLOT_MAGIC) {
+		dbg("%s - bad magic number for slot", function);
+		return -1;
+	}
+	if (!slot->hotplug_slot) {
+		dbg("%s - slot->hotplug_slot == NULL!", function);
+		return -1;
+	}
+	return 0;
+}
+
+static inline struct slot *get_slot (struct hotplug_slot *hotplug_slot, const char *function)
+{ 
+	struct slot *slot;
+
+	if (!hotplug_slot) {
+		dbg("%s - hotplug_slot == NULL\n", function);
+		return NULL;
+	}
+
+	slot = (struct slot *)hotplug_slot->private;
+	if (slot_paranoia_check (slot, function))
+                return NULL;
+	return slot;
+}               
+
+
+static int enable_slot (struct hotplug_slot *hotplug_slot)
+{
+	struct slot *slot = get_slot (hotplug_slot, __FUNCTION__);
+	int retval = 0;
+	
+	if (slot == NULL)
+		return -ENODEV;
+	
+	dbg ("%s - physical_slot = %s\n", __FUNCTION__, hotplug_slot->name);
+
+	/*
+	 * Fill in code here to enable the specified slot
+	 */
+
+	return retval;
+}
+
+
+static int disable_slot (struct hotplug_slot *hotplug_slot)
+{
+	struct slot *slot = get_slot (hotplug_slot, __FUNCTION__);
+	int retval = 0;
+	
+	if (slot == NULL)
+		return -ENODEV;
+	
+	dbg ("%s - physical_slot = %s\n", __FUNCTION__, hotplug_slot->name);
+
+	/*
+	 * Fill in code here to disable the specified slot
+	 */
+
+	return retval;
+}
+
+static int set_attention_status (struct hotplug_slot *hotplug_slot, u8 status)
+{
+	struct slot *slot = get_slot (hotplug_slot, __FUNCTION__);
+	int retval = 0;
+	
+	if (slot == NULL)
+		return -ENODEV;
+	
+	dbg ("%s - physical_slot = %s\n", __FUNCTION__, hotplug_slot->name);
+
+	switch (status) {
+		case 0:
+			/*
+			 * Fill in code here to turn light off
+			 */
+			break;
+
+		case 1:
+		default:
+			/*
+			 * Fill in code here to turn light on
+			 */
+			break;
+	}
+
+	return retval;
+}
+
+static int hardware_test (struct hotplug_slot *hotplug_slot, u32 value)
+{
+	struct slot *slot = get_slot (hotplug_slot, __FUNCTION__);
+	int retval = 0;
+	
+	if (slot == NULL)
+		return -ENODEV;
+	
+	dbg ("%s - physical_slot = %s\n", __FUNCTION__, hotplug_slot->name);
+
+	err ("No hardware tests are defined for this driver");
+	retval = -ENODEV;
+
+	/* Or you can specify a test if you want to */
+	
+	return retval;
+}
+
+static int get_power_status (struct hotplug_slot *hotplug_slot, u8 *value)
+{
+	struct slot *slot = get_slot (hotplug_slot, __FUNCTION__);
+	int retval = 0;
+	
+	if (slot == NULL)
+		return -ENODEV;
+	
+	dbg(__FUNCTION__" - physical_slot = %s\n", hotplug_slot->name);
+
+	/*
+	 * Fill in logic to get the current power status of the specific
+	 * slot and store it in the *value location.
+	 */
+
+	return retval;
+}
+
+static int get_attention_status (struct hotplug_slot *hotplug_slot, u8 *value)
+{
+	struct slot *slot = get_slot (hotplug_slot, __FUNCTION__);
+	int retval = 0;
+	
+	if (slot == NULL)
+		return -ENODEV;
+	
+	dbg(__FUNCTION__" - physical_slot = %s\n", hotplug_slot->name);
+
+	/*
+	 * Fill in logic to get the current attention status of the specific
+	 * slot and store it in the *value location.
+	 */
+
+	return retval;
+}
+
+static int get_latch_status (struct hotplug_slot *hotplug_slot, u8 *value)
+{
+	struct slot *slot = get_slot (hotplug_slot, __FUNCTION__);
+	int retval = 0;
+	
+	if (slot == NULL)
+		return -ENODEV;
+	
+	dbg(__FUNCTION__" - physical_slot = %s\n", hotplug_slot->name);
+
+	/*
+	 * Fill in logic to get the current latch status of the specific
+	 * slot and store it in the *value location.
+	 */
+
+	return retval;
+}
+
+static int get_adapter_status (struct hotplug_slot *hotplug_slot, u8 *value)
+{
+	struct slot *slot = get_slot (hotplug_slot, __FUNCTION__);
+	int retval = 0;
+	
+	if (slot == NULL)
+		return -ENODEV;
+	
+	dbg(__FUNCTION__" - physical_slot = %s\n", hotplug_slot->name);
+
+	/*
+	 * Fill in logic to get the current adapter status of the specific
+	 * slot and store it in the *value location.
+	 */
+
+	return retval;
+}
+
+#define SLOT_NAME_SIZE	10
+static void make_slot_name (struct slot *slot)
+{
+	/*
+	 * Stupid way to make a filename out of the slot name.
+	 * replace this if your hardware provides a better way to name slots.
+	 */
+	snprintf (slot->hotplug_slot->name, SLOT_NAME_SIZE, "%d", slot->number);
+}
+
+static int init_slots (void)
+{
+	struct slot *slot;
+	struct hotplug_slot *hotplug_slot;
+	struct hotplug_slot_info *info;
+	char *name;
+	int retval = 0;
+	int i;
+
+	/*
+	 * Create a structure for each slot, and register that slot
+	 * with the pci_hotplug subsystem.
+	 */
+	for (i = 0; i < num_slots; ++i) {
+		slot = kmalloc (sizeof (struct slot), GFP_KERNEL);
+		if (!slot)
+			return -ENOMEM;
+		memset(slot, 0, sizeof(struct slot));
+
+		hotplug_slot = kmalloc (sizeof (struct hotplug_slot), GFP_KERNEL);
+		if (!hotplug_slot) {
+			kfree (slot);
+			return -ENOMEM;
+		}
+		memset(hotplug_slot, 0, sizeof (struct hotplug_slot));
+		slot->hotplug_slot = hotplug_slot;
+
+		info = kmalloc (sizeof (struct hotplug_slot_info), GFP_KERNEL);
+		if (!info) {
+			kfree (hotplug_slot);
+			kfree (slot);
+			return -ENOMEM;
+		}
+		memset(info, 0, sizeof (struct hotplug_slot_info));
+		hotplug_slot->info = info;
+
+		name = kmalloc (SLOT_NAME_SIZE, GFP_KERNEL);
+		if (!name) {
+			kfree (info);
+			kfree (hotplug_slot);
+			kfree (slot);
+			return -ENOMEM;
+		}
+		hotplug_slot->name = name;
+
+		slot->magic = SLOT_MAGIC;
+		slot->number = i;
+
+		hotplug_slot->private = slot;
+		make_slot_name (slot);
+		hotplug_slot->ops = &skel_hotplug_slot_ops;
+		
+		/*
+		 * Initilize the slot info structure with some known
+		 * good values.
+		 */
+		info->power_status = get_skel_power_status(slot);
+		info->attention_status = get_skel_attention_status(slot);
+		info->latch_status = get_skel_latch_status(slot);
+		info->adapter_status = get_skel_adapter_status(slot);
+		
+		dbg ("registering slot %d\n", i);
+		retval = pci_hp_register (slot->hotplug_slot);
+		if (retval) {
+			err ("pci_hp_register failed with error %d\n", retval);
+			kfree (info);
+			kfree (name);
+			kfree (hotplug_slot);
+			kfree (slot);
+			return retval;
+		}
+
+		/* add slot to our internal list */
+		list_add (&slot->slot_list, &slot_list);
+	}
+
+	return retval;
+}
+		
+static void cleanup_slots (void)
+{
+	struct list_head *tmp;
+	struct slot *slot;
+
+	/*
+	 * Unregister all of our slots with the pci_hotplug subsystem,
+	 * and free up all memory that we had allocated.
+	 */
+	list_for_each (tmp, &slot_list) {
+		slot = list_entry (tmp, struct slot, slot_list);
+		list_del (&slot->slot_list);
+		pci_hp_deregister (slot->hotplug_slot);
+		kfree (slot->hotplug_slot->info);
+		kfree (slot->hotplug_slot->name);
+		kfree (slot->hotplug_slot);
+		kfree (slot);
+	}
+
+	return;
+}
+		
+static int __init pcihp_skel_init(void)
+{
+	int retval;
+
+	/*
+	 * Do specific initialization stuff for your driver here
+	 * Like initilizing your controller hardware (if any) and
+	 * determining the number of slots you have in the system
+	 * right now.
+	 */
+	num_slots = 5;
+
+	retval = init_slots();
+	if (retval)
+		return retval;
+
+	info (DRIVER_DESC " version: " DRIVER_VERSION "\n");
+	return 0;
+}
+
+static void __exit pcihp_skel_exit(void)
+{
+	/*
+	 * Clean everything up.
+	 */
+	cleanup_slots();
+}
+
+module_init(pcihp_skel_init);
+module_exit(pcihp_skel_exit);
+