drivers/pci/hotplug/cpcihp_generic.c

   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 */
  65 static bool debug;
  66 static char *bridge;
  67 static u8 bridge_busnr;
  68 static u8 bridge_slot;
  69 static struct pci_bus *bus;
  70 static u8 first_slot;
  71 static u8 last_slot;
  72 static u16 port;
  73 static unsigned int enum_bit;
  74 static u8 enum_mask;
  75
  76 static struct cpci_hp_controller_ops generic_hpc_ops;
  77 static struct cpci_hp_controller generic_hpc;
  78
  79 static 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
 134 static int query_enum(void)
 135 {
 136         u8 value;
 137
 138         value = inb_p(port);
 139         return ((value & enum_mask) == enum_mask);
 140 }
 141
 142 static 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;
 192 init_start_error:
 193         cpci_hp_unregister_bus(bus);
 194 init_bus_register_error:
 195         cpci_hp_unregister_controller(&generic_hpc);
 196         err("status = %d", status);
 197         return status;
 198
 199 }
 200
 201 static 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
 209 module_init(cpcihp_generic_init);
 210 module_exit(cpcihp_generic_exit);
 211
 212 MODULE_AUTHOR(DRIVER_AUTHOR);
 213 MODULE_DESCRIPTION(DRIVER_DESC);
 214 MODULE_LICENSE("GPL");
 215 module_param(debug, bool, S_IRUGO | S_IWUSR);
 216 MODULE_PARM_DESC(debug, "Debugging mode enabled or not");
 217 module_param(bridge, charp, 0);
 218 MODULE_PARM_DESC(bridge, "Hotswap bus bridge device, <bus>:<slot> (bus and slot are in hexadecimal)");
 219 module_param(first_slot, byte, 0);
 220 MODULE_PARM_DESC(first_slot, "Hotswap bus first slot number");
 221 module_param(last_slot, byte, 0);
 222 MODULE_PARM_DESC(last_slot, "Hotswap bus last slot number");
 223 module_param(port, ushort, 0);
 224 MODULE_PARM_DESC(port, "#ENUM signal I/O port");
 225 module_param(enum_bit, uint, 0);
 226 MODULE_PARM_DESC(enum_bit, "#ENUM signal bit (0-7)");