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/config.h>
  38 #include <linux/module.h>
  39 #include <linux/init.h>
  40 #include <linux/errno.h>
  41 #include <linux/pci.h>
  42 #include <linux/string.h>
  43 #include "cpci_hotplug.h"
  44
  45 #define DRIVER_VERSION  "0.1"
  46 #define DRIVER_AUTHOR   "Scott Murray <scottm@somanetworks.com>"
  47 #define DRIVER_DESC     "Generic port I/O CompactPCI Hot Plug Driver"
  48
  49 #if !defined(MODULE)
  50 #define MY_NAME "cpcihp_generic"
  51 #else
  52 #define MY_NAME THIS_MODULE->name
  53 #endif
  54
  55 #define dbg(format, arg...)                                     \
  56         do {                                                    \
  57                 if(debug)                                       \
  58                         printk (KERN_DEBUG "%s: " format "\n",  \
  59                                 MY_NAME , ## arg);              \
  60         } while(0)
  61 #define err(format, arg...) printk(KERN_ERR "%s: " format "\n", MY_NAME , ## arg)
  62 #define info(format, arg...) printk(KERN_INFO "%s: " format "\n", MY_NAME , ## arg)
  63 #define warn(format, arg...) printk(KERN_WARNING "%s: " format "\n", MY_NAME , ## arg)
  64
  65 /* local variables */
  66 static int debug;
  67 static char *bridge;
  68 static u8 bridge_busnr;
  69 static u8 bridge_slot;
  70 static struct pci_bus *bus;
  71 static u8 first_slot;
  72 static u8 last_slot;
  73 static u16 port;
  74 static unsigned int enum_bit;
  75 static u8 enum_mask;
  76
  77 static struct cpci_hp_controller_ops generic_hpc_ops;
  78 static struct cpci_hp_controller generic_hpc;
  79
  80 static int __init validate_parameters(void)
  81 {
  82         char* str;
  83         char* p;
  84         unsigned long tmp;
  85
  86         if(!bridge) {
  87                 info("not configured, disabling.");
  88                 return 1;
  89         }
  90         str = bridge;
  91         if(!*str)
  92                 return -EINVAL;
  93
  94         tmp = simple_strtoul(str, &p, 16);
  95         if(p == str || tmp > 0xff) {
  96                 err("Invalid hotplug bus bridge device bus number");
  97                 return -EINVAL;
  98         }
  99         bridge_busnr = (u8) tmp;
 100         dbg("bridge_busnr = 0x%02x", bridge_busnr);
 101         if(*p != ':') {
 102                 err("Invalid hotplug bus bridge device");
 103                 return -EINVAL;
 104         }
 105         str = p + 1;
 106         tmp = simple_strtoul(str, &p, 16);
 107         if(p == str || tmp > 0x1f) {
 108                 err("Invalid hotplug bus bridge device slot number");
 109                 return -EINVAL;
 110         }
 111         bridge_slot = (u8) tmp;
 112         dbg("bridge_slot = 0x%02x", bridge_slot);
 113
 114         dbg("first_slot = 0x%02x", first_slot);
 115         dbg("last_slot = 0x%02x", last_slot);
 116         if(!(first_slot && last_slot)) {
 117                 err("Need to specify first_slot and last_slot");
 118                 return -EINVAL;
 119         }
 120         if(last_slot < first_slot) {
 121                 err("first_slot must be less than last_slot");
 122                 return -EINVAL;
 123         }
 124
 125         dbg("port = 0x%04x", port);
 126         dbg("enum_bit = 0x%02x", enum_bit);
 127         if(enum_bit > 7) {
 128                 err("Invalid #ENUM bit");
 129                 return -EINVAL;
 130         }
 131         enum_mask = 1 << enum_bit;
 132         return 0;
 133 }
 134
 135 static int query_enum(void)
 136 {
 137         u8 value;
 138
 139         value = inb_p(port);
 140         return ((value & enum_mask) == enum_mask);
 141 }
 142
 143 static int __init cpcihp_generic_init(void)
 144 {
 145         int status;
 146         struct resource* r;
 147         struct pci_dev* dev;
 148
 149         info(DRIVER_DESC " version: " DRIVER_VERSION);
 150         status = validate_parameters();
 151         if(status != 0)
 152                 return status;
 153
 154         r = request_region(port, 1, "#ENUM hotswap signal register");
 155         if(!r)
 156                 return -EBUSY;
 157
 158         dev = pci_find_slot(bridge_busnr, PCI_DEVFN(bridge_slot, 0));
 159         if(!dev || dev->hdr_type != PCI_HEADER_TYPE_BRIDGE) {
 160                 err("Invalid bridge device %s", bridge);
 161                 return -EINVAL;
 162         }
 163         bus = dev->subordinate;
 164
 165         memset(&generic_hpc, 0, sizeof (struct cpci_hp_controller));
 166         generic_hpc_ops.query_enum = query_enum;
 167         generic_hpc.ops = &generic_hpc_ops;
 168
 169         status = cpci_hp_register_controller(&generic_hpc);
 170         if(status != 0) {
 171                 err("Could not register cPCI hotplug controller");
 172                 return -ENODEV;
 173         }
 174         dbg("registered controller");
 175
 176         status = cpci_hp_register_bus(bus, first_slot, last_slot);
 177         if(status != 0) {
 178                 err("Could not register cPCI hotplug bus");
 179                 goto init_bus_register_error;
 180         }
 181         dbg("registered bus");
 182
 183         status = cpci_hp_start();
 184         if(status != 0) {
 185                 err("Could not started cPCI hotplug system");
 186                 goto init_start_error;
 187         }
 188         dbg("started cpci hp system");
 189         return 0;
 190 init_start_error:
 191         cpci_hp_unregister_bus(bus);
 192 init_bus_register_error:
 193         cpci_hp_unregister_controller(&generic_hpc);
 194         err("status = %d", status);
 195         return status;
 196
 197 }
 198
 199 static void __exit cpcihp_generic_exit(void)
 200 {
 201         cpci_hp_stop();
 202         cpci_hp_unregister_bus(bus);
 203         cpci_hp_unregister_controller(&generic_hpc);
 204         release_region(port, 1);
 205 }
 206
 207 module_init(cpcihp_generic_init);
 208 module_exit(cpcihp_generic_exit);
 209
 210 MODULE_AUTHOR(DRIVER_AUTHOR);
 211 MODULE_DESCRIPTION(DRIVER_DESC);
 212 MODULE_LICENSE("GPL");
 213 module_param(debug, bool, S_IRUGO | S_IWUSR);
 214 MODULE_PARM_DESC(debug, "Debugging mode enabled or not");
 215 module_param(bridge, charp, 0);
 216 MODULE_PARM_DESC(bridge, "Hotswap bus bridge device, <bus>:<slot> (bus and slot are in hexadecimal)");
 217 module_param(first_slot, byte, 0);
 218 MODULE_PARM_DESC(first_slot, "Hotswap bus first slot number");
 219 module_param(last_slot, byte, 0);
 220 MODULE_PARM_DESC(last_slot, "Hotswap bus last slot number");
 221 module_param(port, ushort, 0);
 222 MODULE_PARM_DESC(port, "#ENUM signal I/O port");
 223 module_param(enum_bit, uint, 0);
 224 MODULE_PARM_DESC(enum_bit, "#ENUM signal bit (0-7)");