Linux Audio

Check our new training course

Loading...
Note: File does not exist in v5.4.
  1/*
  2 * PCI Hot Plug Controller Skeleton Driver - 0.3
  3 *
  4 * Copyright (C) 2001,2003 Greg Kroah-Hartman (greg@kroah.com)
  5 * Copyright (C) 2001,2003 IBM Corp.
  6 *
  7 * All rights reserved.
  8 *
  9 * This program is free software; you can redistribute it and/or modify
 10 * it under the terms of the GNU General Public License as published by
 11 * the Free Software Foundation; either version 2 of the License, or (at
 12 * your option) any later version.
 13 *
 14 * This program is distributed in the hope that it will be useful, but
 15 * WITHOUT ANY WARRANTY; without even the implied warranty of
 16 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
 17 * NON INFRINGEMENT.  See the GNU General Public License for more
 18 * details.
 19 *
 20 * You should have received a copy of the GNU General Public License
 21 * along with this program; if not, write to the Free Software
 22 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 23 *
 24 * This driver is to be used as a skeleton driver to show how to interface
 25 * with the pci hotplug core easily.
 26 *
 27 * Send feedback to <greg@kroah.com>
 28 *
 29 */
 30
 31#include <linux/module.h>
 32#include <linux/moduleparam.h>
 33#include <linux/kernel.h>
 34#include <linux/slab.h>
 35#include <linux/pci.h>
 36#include <linux/pci_hotplug.h>
 37#include <linux/init.h>
 38
 39#define SLOT_NAME_SIZE	10
 40struct slot {
 41	u8 number;
 42	struct hotplug_slot *hotplug_slot;
 43	struct list_head slot_list;
 44	char name[SLOT_NAME_SIZE];
 45};
 46
 47static LIST_HEAD(slot_list);
 48
 49#define MY_NAME	"pcihp_skeleton"
 50
 51#define dbg(format, arg...)					\
 52	do {							\
 53		if (debug)					\
 54			printk(KERN_DEBUG "%s: " format "\n",	\
 55				MY_NAME, ## arg);		\
 56	} while (0)
 57#define err(format, arg...) printk(KERN_ERR "%s: " format "\n", MY_NAME, ## arg)
 58#define info(format, arg...) printk(KERN_INFO "%s: " format "\n", MY_NAME, ## arg)
 59#define warn(format, arg...) printk(KERN_WARNING "%s: " format "\n", MY_NAME, ## arg)
 60
 61/* local variables */
 62static bool debug;
 63static int num_slots;
 64
 65#define DRIVER_VERSION	"0.3"
 66#define DRIVER_AUTHOR	"Greg Kroah-Hartman <greg@kroah.com>"
 67#define DRIVER_DESC	"Hot Plug PCI Controller Skeleton Driver"
 68
 69MODULE_AUTHOR(DRIVER_AUTHOR);
 70MODULE_DESCRIPTION(DRIVER_DESC);
 71MODULE_LICENSE("GPL");
 72module_param(debug, bool, 0644);
 73MODULE_PARM_DESC(debug, "Debugging mode enabled or not");
 74
 75static int enable_slot(struct hotplug_slot *slot);
 76static int disable_slot(struct hotplug_slot *slot);
 77static int set_attention_status(struct hotplug_slot *slot, u8 value);
 78static int hardware_test(struct hotplug_slot *slot, u32 value);
 79static int get_power_status(struct hotplug_slot *slot, u8 *value);
 80static int get_attention_status(struct hotplug_slot *slot, u8 *value);
 81static int get_latch_status(struct hotplug_slot *slot, u8 *value);
 82static int get_adapter_status(struct hotplug_slot *slot, u8 *value);
 83
 84static struct hotplug_slot_ops skel_hotplug_slot_ops = {
 85	.enable_slot =		enable_slot,
 86	.disable_slot =		disable_slot,
 87	.set_attention_status =	set_attention_status,
 88	.hardware_test =	hardware_test,
 89	.get_power_status =	get_power_status,
 90	.get_attention_status =	get_attention_status,
 91	.get_latch_status =	get_latch_status,
 92	.get_adapter_status =	get_adapter_status,
 93};
 94
 95static int enable_slot(struct hotplug_slot *hotplug_slot)
 96{
 97	struct slot *slot = hotplug_slot->private;
 98	int retval = 0;
 99
100	dbg("%s - physical_slot = %s\n", __func__, hotplug_slot->name);
101
102	/*
103	 * Fill in code here to enable the specified slot
104	 */
105
106	return retval;
107}
108
109static int disable_slot(struct hotplug_slot *hotplug_slot)
110{
111	struct slot *slot = hotplug_slot->private;
112	int retval = 0;
113
114	dbg("%s - physical_slot = %s\n", __func__, hotplug_slot->name);
115
116	/*
117	 * Fill in code here to disable the specified slot
118	 */
119
120	return retval;
121}
122
123static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 status)
124{
125	struct slot *slot = hotplug_slot->private;
126	int retval = 0;
127
128	dbg("%s - physical_slot = %s\n", __func__, hotplug_slot->name);
129
130	switch (status) {
131	case 0:
132		/*
133		 * Fill in code here to turn light off
134		 */
135		break;
136
137	case 1:
138	default:
139		/*
140		 * Fill in code here to turn light on
141		 */
142		break;
143	}
144
145	return retval;
146}
147
148static int hardware_test(struct hotplug_slot *hotplug_slot, u32 value)
149{
150	struct slot *slot = hotplug_slot->private;
151	int retval = 0;
152
153	dbg("%s - physical_slot = %s\n", __func__, hotplug_slot->name);
154
155	switch (value) {
156	case 0:
157		/* Specify a test here */
158		break;
159	case 1:
160		/* Specify another test here */
161		break;
162	}
163
164	return retval;
165}
166
167static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
168{
169	struct slot *slot = hotplug_slot->private;
170	int retval = 0;
171
172	dbg("%s - physical_slot = %s\n", __func__, hotplug_slot->name);
173
174	/*
175	 * Fill in logic to get the current power status of the specific
176	 * slot and store it in the *value location.
177	 */
178
179	return retval;
180}
181
182static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 *value)
183{
184	struct slot *slot = hotplug_slot->private;
185	int retval = 0;
186
187	dbg("%s - physical_slot = %s\n", __func__, hotplug_slot->name);
188
189	/*
190	 * Fill in logic to get the current attention status of the specific
191	 * slot and store it in the *value location.
192	 */
193
194	return retval;
195}
196
197static int get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value)
198{
199	struct slot *slot = hotplug_slot->private;
200	int retval = 0;
201
202	dbg("%s - physical_slot = %s\n", __func__, hotplug_slot->name);
203
204	/*
205	 * Fill in logic to get the current latch status of the specific
206	 * slot and store it in the *value location.
207	 */
208
209	return retval;
210}
211
212static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
213{
214	struct slot *slot = hotplug_slot->private;
215	int retval = 0;
216
217	dbg("%s - physical_slot = %s\n", __func__, hotplug_slot->name);
218
219	/*
220	 * Fill in logic to get the current adapter status of the specific
221	 * slot and store it in the *value location.
222	 */
223
224	return retval;
225}
226
227static void release_slot(struct hotplug_slot *hotplug_slot)
228{
229	struct slot *slot = hotplug_slot->private;
230
231	dbg("%s - physical_slot = %s\n", __func__, hotplug_slot->name);
232	kfree(slot->hotplug_slot->info);
233	kfree(slot->hotplug_slot);
234	kfree(slot);
235}
236
237static void make_slot_name(struct slot *slot)
238{
239	/*
240	 * Stupid way to make a filename out of the slot name.
241	 * replace this if your hardware provides a better way to name slots.
242	 */
243	snprintf(slot->hotplug_slot->name, SLOT_NAME_SIZE, "%d", slot->number);
244}
245
246/**
247 * init_slots - initialize 'struct slot' structures for each slot
248 *
249 */
250static int __init init_slots(void)
251{
252	struct slot *slot;
253	struct hotplug_slot *hotplug_slot;
254	struct hotplug_slot_info *info;
255	int retval;
256	int i;
257
258	/*
259	 * Create a structure for each slot, and register that slot
260	 * with the pci_hotplug subsystem.
261	 */
262	for (i = 0; i < num_slots; ++i) {
263		slot = kzalloc(sizeof(*slot), GFP_KERNEL);
264		if (!slot) {
265			retval = -ENOMEM;
266			goto error;
267		}
268
269		hotplug_slot = kzalloc(sizeof(*hotplug_slot), GFP_KERNEL);
270		if (!hotplug_slot) {
271			retval = -ENOMEM;
272			goto error_slot;
273		}
274		slot->hotplug_slot = hotplug_slot;
275
276		info = kzalloc(sizeof(*info), GFP_KERNEL);
277		if (!info) {
278			retval = -ENOMEM;
279			goto error_hpslot;
280		}
281		hotplug_slot->info = info;
282
283		slot->number = i;
284
285		hotplug_slot->name = slot->name;
286		hotplug_slot->private = slot;
287		hotplug_slot->release = &release_slot;
288		make_slot_name(slot);
289		hotplug_slot->ops = &skel_hotplug_slot_ops;
290
291		/*
292		 * Initialize the slot info structure with some known
293		 * good values.
294		 */
295		get_power_status(hotplug_slot, &info->power_status);
296		get_attention_status(hotplug_slot, &info->attention_status);
297		get_latch_status(hotplug_slot, &info->latch_status);
298		get_adapter_status(hotplug_slot, &info->adapter_status);
299
300		dbg("registering slot %d\n", i);
301		retval = pci_hp_register(slot->hotplug_slot);
302		if (retval) {
303			err("pci_hp_register failed with error %d\n", retval);
304			goto error_info;
305		}
306
307		/* add slot to our internal list */
308		list_add(&slot->slot_list, &slot_list);
309	}
310
311	return 0;
312error_info:
313	kfree(info);
314error_hpslot:
315	kfree(hotplug_slot);
316error_slot:
317	kfree(slot);
318error:
319	return retval;
320}
321
322static void __exit cleanup_slots(void)
323{
324	struct slot *slot, *next;
325
326	/*
327	 * Unregister all of our slots with the pci_hotplug subsystem.
328	 * Memory will be freed in release_slot() callback after slot's
329	 * lifespan is finished.
330	 */
331	list_for_each_entry_safe(slot, next, &slot_list, slot_list) {
332		list_del(&slot->slot_list);
333		pci_hp_deregister(slot->hotplug_slot);
334	}
335}
336
337static int __init pcihp_skel_init(void)
338{
339	int retval;
340
341	info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
342	/*
343	 * Do specific initialization stuff for your driver here
344	 * like initializing your controller hardware (if any) and
345	 * determining the number of slots you have in the system
346	 * right now.
347	 */
348	num_slots = 5;
349
350	return init_slots();
351}
352
353static void __exit pcihp_skel_exit(void)
354{
355	/*
356	 * Clean everything up.
357	 */
358	cleanup_slots();
359}
360
361module_init(pcihp_skel_init);
362module_exit(pcihp_skel_exit);