drivers/misc/hdpuftrs/hdpu_nexus.c

   1 /*
   2  *      Sky Nexus Register Driver
   3  *
   4  *      Copyright (C) 2002 Brian Waite
   5  *
   6  *      This driver allows reading the Nexus register
   7  *      It exports the /proc/sky_chassis_id and also
   8  *      /proc/sky_slot_id pseudo-file for status information.
   9  *
  10  *      This program is free software; you can redistribute it and/or
  11  *      modify it under the terms of the GNU General Public License
  12  *      as published by the Free Software Foundation; either version
  13  *      2 of the License, or (at your option) any later version.
  14  *
  15  */
  16
  17 #include <linux/version.h>
  18 #include <linux/module.h>
  19 #include <linux/kernel.h>
  20 #include <linux/proc_fs.h>
  21 #include <linux/hdpu_features.h>
  22 #include <linux/pci.h>
  23
  24 #include <linux/device.h>
  25
  26 static int hdpu_nexus_probe(struct device *ddev);
  27 static int hdpu_nexus_remove(struct device *ddev);
  28
  29 static struct proc_dir_entry *hdpu_slot_id;
  30 static struct proc_dir_entry *hdpu_chassis_id;
  31 static int slot_id = -1;
  32 static int chassis_id = -1;
  33
  34 static struct device_driver hdpu_nexus_driver = {
  35         .name = HDPU_NEXUS_NAME,
  36         .bus = &platform_bus_type,
  37         .probe = hdpu_nexus_probe,
  38         .remove = hdpu_nexus_remove,
  39 };
  40
  41 int hdpu_slot_id_read(char *buffer, char **buffer_location, off_t offset,
  42                       int buffer_length, int *zero, void *ptr)
  43 {
  44
  45         if (offset > 0)
  46                 return 0;
  47         return sprintf(buffer, "%d\n", slot_id);
  48 }
  49
  50 int hdpu_chassis_id_read(char *buffer, char **buffer_location, off_t offset,
  51                          int buffer_length, int *zero, void *ptr)
  52 {
  53
  54         if (offset > 0)
  55                 return 0;
  56         return sprintf(buffer, "%d\n", chassis_id);
  57 }
  58
  59 static int hdpu_nexus_probe(struct device *ddev)
  60 {
  61         struct platform_device *pdev = to_platform_device(ddev);
  62         struct resource *res;
  63
  64         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  65         int *nexus_id_addr;
  66         nexus_id_addr =
  67             ioremap(res->start, (unsigned long)(res->end - res->start));
  68         if (nexus_id_addr) {
  69                 slot_id = (*nexus_id_addr >> 8) & 0x1f;
  70                 chassis_id = *nexus_id_addr & 0xff;
  71                 iounmap(nexus_id_addr);
  72         } else
  73                 printk("Could not map slot id\n");
  74         hdpu_slot_id = create_proc_entry("sky_slot_id", 0666, &proc_root);
  75         hdpu_slot_id->read_proc = hdpu_slot_id_read;
  76         hdpu_slot_id->nlink = 1;
  77
  78         hdpu_chassis_id = create_proc_entry("sky_chassis_id", 0666, &proc_root);
  79         hdpu_chassis_id->read_proc = hdpu_chassis_id_read;
  80         hdpu_chassis_id->nlink = 1;
  81         return 0;
  82 }
  83
  84 static int hdpu_nexus_remove(struct device *ddev)
  85 {
  86         slot_id = -1;
  87         chassis_id = -1;
  88         remove_proc_entry("sky_slot_id", &proc_root);
  89         remove_proc_entry("sky_chassis_id", &proc_root);
  90         hdpu_slot_id = 0;
  91         hdpu_chassis_id = 0;
  92         return 0;
  93 }
  94
  95 static int __init nexus_init(void)
  96 {
  97         int rc;
  98         rc = driver_register(&hdpu_nexus_driver);
  99         return rc;
 100 }
 101
 102 static void __exit nexus_exit(void)
 103 {
 104         driver_unregister(&hdpu_nexus_driver);
 105 }
 106
 107 module_init(nexus_init);
 108 module_exit(nexus_exit);
 109
 110 MODULE_AUTHOR("Brian Waite");
 111 MODULE_LICENSE("GPL");