1/*
2 * cpcihp_generic.c
3 *
4 * Generic port I/O CompactPCI driver
5 *
6 * Copyright 2002 SOMA Networks, Inc.
7 * Copyright 2001 Intel San Luis Obispo
8 * Copyright 2000,2001 MontaVista Software Inc.
9 *
10 * This program is free software; you can redistribute it and/or modify it
11 * under the terms of the GNU General Public License as published by the
12 * Free Software Foundation; either version 2 of the License, or (at your
13 * option) any later version.
14 *
15 * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
16 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
17 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
18 * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
19 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
20 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
21 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
22 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
23 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
24 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 *
26 * You should have received a copy of the GNU General Public License along
27 * with this program; if not, write to the Free Software Foundation, Inc.,
28 * 675 Mass Ave, Cambridge, MA 02139, USA.
29 *
30 * This generic CompactPCI hotplug driver should allow using the PCI hotplug
31 * mechanism on any CompactPCI board that exposes the #ENUM signal as a bit
32 * in a system register that can be read through standard port I/O.
33 *
34 * Send feedback to <scottm@somanetworks.com>
35 */
36
37#include <linux/module.h>
38#include <linux/init.h>
39#include <linux/errno.h>
40#include <linux/pci.h>
41#include <linux/string.h>
42#include "cpci_hotplug.h"
43
44#define DRIVER_VERSION	"0.1"
45#define DRIVER_AUTHOR	"Scott Murray <scottm@somanetworks.com>"
46#define DRIVER_DESC	"Generic port I/O CompactPCI Hot Plug Driver"
47
48#if !defined(MODULE)
49#define MY_NAME	"cpcihp_generic"
50#else
51#define MY_NAME	THIS_MODULE->name
52#endif
53
54#define dbg(format, arg...)					\
55	do {							\
56		if (debug)					\
57			printk (KERN_DEBUG "%s: " format "\n",	\
58				MY_NAME , ## arg);		\
59	} while (0)
60#define err(format, arg...) printk(KERN_ERR "%s: " format "\n", MY_NAME , ## arg)
61#define info(format, arg...) printk(KERN_INFO "%s: " format "\n", MY_NAME , ## arg)
62#define warn(format, arg...) printk(KERN_WARNING "%s: " format "\n", MY_NAME , ## arg)
63
64/* local variables */
65static bool debug;
66static char *bridge;
67static u8 bridge_busnr;
68static u8 bridge_slot;
69static struct pci_bus *bus;
70static u8 first_slot;
71static u8 last_slot;
72static u16 port;
73static unsigned int enum_bit;
74static u8 enum_mask;
75
76static struct cpci_hp_controller_ops generic_hpc_ops;
77static struct cpci_hp_controller generic_hpc;
78
79static int __init validate_parameters(void)
80{
81	char *str;
82	char *p;
83	unsigned long tmp;
84
85	if (!bridge) {
86		info("not configured, disabling.");
87		return -EINVAL;
88	}
89	str = bridge;
90	if (!*str)
91		return -EINVAL;
92
93	tmp = simple_strtoul(str, &p, 16);
94	if (p == str || tmp > 0xff) {
95		err("Invalid hotplug bus bridge device bus number");
96		return -EINVAL;
97	}
98	bridge_busnr = (u8) tmp;
99	dbg("bridge_busnr = 0x%02x", bridge_busnr);
100	if (*p != ':') {
101		err("Invalid hotplug bus bridge device");
102		return -EINVAL;
103	}
104	str = p + 1;
105	tmp = simple_strtoul(str, &p, 16);
106	if (p == str || tmp > 0x1f) {
107		err("Invalid hotplug bus bridge device slot number");
108		return -EINVAL;
109	}
110	bridge_slot = (u8) tmp;
111	dbg("bridge_slot = 0x%02x", bridge_slot);
112
113	dbg("first_slot = 0x%02x", first_slot);
114	dbg("last_slot = 0x%02x", last_slot);
115	if (!(first_slot && last_slot)) {
116		err("Need to specify first_slot and last_slot");
117		return -EINVAL;
118	}
119	if (last_slot < first_slot) {
120		err("first_slot must be less than last_slot");
121		return -EINVAL;
122	}
123
124	dbg("port = 0x%04x", port);
125	dbg("enum_bit = 0x%02x", enum_bit);
126	if (enum_bit > 7) {
127		err("Invalid #ENUM bit");
128		return -EINVAL;
129	}
130	enum_mask = 1 << enum_bit;
131	return 0;
132}
133
134static int query_enum(void)
135{
136	u8 value;
137
138	value = inb_p(port);
139	return ((value & enum_mask) == enum_mask);
140}
141
142static int __init cpcihp_generic_init(void)
143{
144	int status;
145	struct resource *r;
146	struct pci_dev *dev;
147
148	info(DRIVER_DESC " version: " DRIVER_VERSION);
149	status = validate_parameters();
150	if (status)
151		return status;
152
153	r = request_region(port, 1, "#ENUM hotswap signal register");
154	if (!r)
155		return -EBUSY;
156
157	dev = pci_get_domain_bus_and_slot(0, bridge_busnr,
158					  PCI_DEVFN(bridge_slot, 0));
159	if (!dev || dev->hdr_type != PCI_HEADER_TYPE_BRIDGE) {
160		err("Invalid bridge device %s", bridge);
161		pci_dev_put(dev);
162		return -EINVAL;
163	}
164	bus = dev->subordinate;
165	pci_dev_put(dev);
166
167	memset(&generic_hpc, 0, sizeof (struct cpci_hp_controller));
168	generic_hpc_ops.query_enum = query_enum;
169	generic_hpc.ops = &generic_hpc_ops;
170
171	status = cpci_hp_register_controller(&generic_hpc);
172	if (status != 0) {
173		err("Could not register cPCI hotplug controller");
174		return -ENODEV;
175	}
176	dbg("registered controller");
177
178	status = cpci_hp_register_bus(bus, first_slot, last_slot);
179	if (status != 0) {
180		err("Could not register cPCI hotplug bus");
181		goto init_bus_register_error;
182	}
183	dbg("registered bus");
184
185	status = cpci_hp_start();
186	if (status != 0) {
187		err("Could not started cPCI hotplug system");
188		goto init_start_error;
189	}
190	dbg("started cpci hp system");
191	return 0;
192init_start_error:
193	cpci_hp_unregister_bus(bus);
194init_bus_register_error:
195	cpci_hp_unregister_controller(&generic_hpc);
196	err("status = %d", status);
197	return status;
198
199}
200
201static void __exit cpcihp_generic_exit(void)
202{
203	cpci_hp_stop();
204	cpci_hp_unregister_bus(bus);
205	cpci_hp_unregister_controller(&generic_hpc);
206	release_region(port, 1);
207}
208
209module_init(cpcihp_generic_init);
210module_exit(cpcihp_generic_exit);
211
212MODULE_AUTHOR(DRIVER_AUTHOR);
213MODULE_DESCRIPTION(DRIVER_DESC);
214MODULE_LICENSE("GPL");
215module_param(debug, bool, S_IRUGO | S_IWUSR);
216MODULE_PARM_DESC(debug, "Debugging mode enabled or not");
217module_param(bridge, charp, 0);
218MODULE_PARM_DESC(bridge, "Hotswap bus bridge device, <bus>:<slot> (bus and slot are in hexadecimal)");
219module_param(first_slot, byte, 0);
220MODULE_PARM_DESC(first_slot, "Hotswap bus first slot number");
221module_param(last_slot, byte, 0);
222MODULE_PARM_DESC(last_slot, "Hotswap bus last slot number");
223module_param(port, ushort, 0);
224MODULE_PARM_DESC(port, "#ENUM signal I/O port");
225module_param(enum_bit, uint, 0);
226MODULE_PARM_DESC(enum_bit, "#ENUM signal bit (0-7)");
227