summaryrefslogtreecommitdiff
path: root/drivers/pci/hotplug/pcihp_skeleton.c
blob: ac69094e4b2089804ce41b00730d81c487adebf7 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
/*
 * PCI Hot Plug Controller Skeleton Driver - 0.3
 *
 * Copyright (C) 2001,2003 Greg Kroah-Hartman (greg@kroah.com)
 * Copyright (C) 2001,2003 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 show how to interface
 * with the pci hotplug core easily.
 *
 * Send feedback to <greg@kroah.com>
 *
 */

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/pci.h>
#include <linux/pci_hotplug.h>
#include <linux/init.h>

#define SLOT_NAME_SIZE	10
struct slot {
	u8 number;
	struct hotplug_slot *hotplug_slot;
	struct list_head slot_list;
	char name[SLOT_NAME_SIZE];
};

static LIST_HEAD(slot_list);

#define MY_NAME	"pcihp_skeleton"

#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 bool debug;
static int num_slots;

#define DRIVER_VERSION	"0.3"
#define DRIVER_AUTHOR	"Greg Kroah-Hartman <greg@kroah.com>"
#define DRIVER_DESC	"Hot Plug PCI Controller Skeleton Driver"

MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");
module_param(debug, bool, 0644);
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 = {
	.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,
};

static int enable_slot(struct hotplug_slot *hotplug_slot)
{
	struct slot *slot = hotplug_slot->private;
	int retval = 0;

	dbg("%s - physical_slot = %s\n", __func__, 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 = hotplug_slot->private;
	int retval = 0;

	dbg("%s - physical_slot = %s\n", __func__, 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 = hotplug_slot->private;
	int retval = 0;

	dbg("%s - physical_slot = %s\n", __func__, 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 = hotplug_slot->private;
	int retval = 0;

	dbg("%s - physical_slot = %s\n", __func__, hotplug_slot->name);

	switch (value) {
		case 0:
			/* Specify a test here */
			break;
		case 1:
			/* Specify another test here */
			break;
	}

	return retval;
}

static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
{
	struct slot *slot = hotplug_slot->private;
	int retval = 0;

	dbg("%s - physical_slot = %s\n", __func__, 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 = hotplug_slot->private;
	int retval = 0;

	dbg("%s - physical_slot = %s\n", __func__, 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 = hotplug_slot->private;
	int retval = 0;

	dbg("%s - physical_slot = %s\n", __func__, 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 = hotplug_slot->private;
	int retval = 0;

	dbg("%s - physical_slot = %s\n", __func__, 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;
}

static void release_slot(struct hotplug_slot *hotplug_slot)
{
	struct slot *slot = hotplug_slot->private;

	dbg("%s - physical_slot = %s\n", __func__, hotplug_slot->name);
	kfree(slot->hotplug_slot->info);
	kfree(slot->hotplug_slot);
	kfree(slot);
}

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);
}

/**
 * init_slots - initialize 'struct slot' structures for each slot
 *
 */
static int __init init_slots(void)
{
	struct slot *slot;
	struct hotplug_slot *hotplug_slot;
	struct hotplug_slot_info *info;
	int retval;
	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 = kzalloc(sizeof(*slot), GFP_KERNEL);
		if (!slot) {
			retval = -ENOMEM;
			goto error;
		}

		hotplug_slot = kzalloc(sizeof(*hotplug_slot), GFP_KERNEL);
		if (!hotplug_slot) {
			retval = -ENOMEM;
			goto error_slot;
		}
		slot->hotplug_slot = hotplug_slot;

		info = kzalloc(sizeof(*info), GFP_KERNEL);
		if (!info) {
			retval = -ENOMEM;
			goto error_hpslot;
		}
		hotplug_slot->info = info;

		slot->number = i;

		hotplug_slot->name = slot->name;
		hotplug_slot->private = slot;
		hotplug_slot->release = &release_slot;
		make_slot_name(slot);
		hotplug_slot->ops = &skel_hotplug_slot_ops;

		/*
		 * Initialize the slot info structure with some known
		 * good values.
		 */
		get_power_status(hotplug_slot, &info->power_status);
		get_attention_status(hotplug_slot, &info->attention_status);
		get_latch_status(hotplug_slot, &info->latch_status);
		get_adapter_status(hotplug_slot, &info->adapter_status);

		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);
			goto error_info;
		}

		/* add slot to our internal list */
		list_add(&slot->slot_list, &slot_list);
	}

	return 0;
error_info:
	kfree(info);
error_hpslot:
	kfree(hotplug_slot);
error_slot:
	kfree(slot);
error:
	return retval;
}

static void __exit cleanup_slots(void)
{
	struct list_head *tmp;
	struct list_head *next;
	struct slot *slot;

	/*
	 * Unregister all of our slots with the pci_hotplug subsystem.
	 * Memory will be freed in release_slot() callback after slot's
	 * lifespan is finished.
	 */
	list_for_each_safe(tmp, next, &slot_list) {
		slot = list_entry(tmp, struct slot, slot_list);
		list_del(&slot->slot_list);
		pci_hp_deregister(slot->hotplug_slot);
	}
}

static int __init pcihp_skel_init(void)
{
	int retval;

	info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
	/*
	 * Do specific initialization stuff for your driver here
	 * like initializing your controller hardware (if any) and
	 * determining the number of slots you have in the system
	 * right now.
	 */
	num_slots = 5;

	return init_slots();
}

static void __exit pcihp_skel_exit(void)
{
	/*
	 * Clean everything up.
	 */
	cleanup_slots();
}

module_init(pcihp_skel_init);
module_exit(pcihp_skel_exit);