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/module.h>
  18 #include <linux/kernel.h>
  19 #include <linux/proc_fs.h>
  20 #include <linux/hdpu_features.h>
  21 #include <linux/platform_device.h>
  22 #include <linux/seq_file.h>
  23 #include <asm/io.h>
  24
  25 static int hdpu_nexus_probe(struct platform_device *pdev);
  26 static int hdpu_nexus_remove(struct platform_device *pdev);
  27 static int hdpu_slot_id_open(struct inode *inode, struct file *file);
  28 static int hdpu_slot_id_read(struct seq_file *seq, void *offset);
  29 static int hdpu_chassis_id_open(struct inode *inode, struct file *file);
  30 static int hdpu_chassis_id_read(struct seq_file *seq, void *offset);
  31
  32 static struct proc_dir_entry *hdpu_slot_id;
  33 static struct proc_dir_entry *hdpu_chassis_id;
  34 static int slot_id = -1;
  35 static int chassis_id = -1;
  36
  37 static const struct file_operations proc_slot_id = {
  38         .open = hdpu_slot_id_open,
  39         .read = seq_read,
  40         .llseek = seq_lseek,
  41         .release = single_release,
  42         .owner = THIS_MODULE,
  43 };
  44
  45 static const struct file_operations proc_chassis_id = {
  46         .open = hdpu_chassis_id_open,
  47         .read = seq_read,
  48         .llseek = seq_lseek,
  49         .release = single_release,
  50         .owner = THIS_MODULE,
  51 };
  52
  53 static struct platform_driver hdpu_nexus_driver = {
  54         .probe = hdpu_nexus_probe,
  55         .remove = hdpu_nexus_remove,
  56         .driver = {
  57                 .name = HDPU_NEXUS_NAME,
  58                 .owner = THIS_MODULE,
  59         },
  60 };
  61
  62 static int hdpu_slot_id_open(struct inode *inode, struct file *file)
  63 {
  64         return single_open(file, hdpu_slot_id_read, NULL);
  65 }
  66
  67 static int hdpu_slot_id_read(struct seq_file *seq, void *offset)
  68 {
  69         seq_printf(seq, "%d\n", slot_id);
  70         return 0;
  71 }
  72
  73 static int hdpu_chassis_id_open(struct inode *inode, struct file *file)
  74 {
  75         return single_open(file, hdpu_chassis_id_read, NULL);
  76 }
  77
  78 static int hdpu_chassis_id_read(struct seq_file *seq, void *offset)
  79 {
  80         seq_printf(seq, "%d\n", chassis_id);
  81         return 0;
  82 }
  83
  84 static int hdpu_nexus_probe(struct platform_device *pdev)
  85 {
  86         struct resource *res;
  87         int *nexus_id_addr;
  88
  89         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  90         if (!res) {
  91                 printk(KERN_ERR "sky_nexus: "
  92                        "Invalid memory resource.\n");
  93                 return -EINVAL;
  94         }
  95         nexus_id_addr = ioremap(res->start,
  96                                 (unsigned long)(res->end - res->start));
  97         if (nexus_id_addr) {
  98                 slot_id = (*nexus_id_addr >> 8) & 0x1f;
  99                 chassis_id = *nexus_id_addr & 0xff;
 100                 iounmap(nexus_id_addr);
 101         } else {
 102                 printk(KERN_ERR "sky_nexus: Could not map slot id\n");
 103         }
 104
 105         hdpu_slot_id = create_proc_entry("sky_slot_id", 0666, &proc_root);
 106         if (!hdpu_slot_id) {
 107                 printk(KERN_WARNING "sky_nexus: "
 108                        "Unable to create proc dir entry: sky_slot_id\n");
 109         } else {
 110                 hdpu_slot_id->proc_fops = &proc_slot_id;
 111                 hdpu_slot_id->owner = THIS_MODULE;
 112         }
 113
 114         hdpu_chassis_id = create_proc_entry("sky_chassis_id", 0666, &proc_root);
 115         if (!hdpu_chassis_id) {
 116                 printk(KERN_WARNING "sky_nexus: "
 117                        "Unable to create proc dir entry: sky_chassis_id\n");
 118         } else {
 119                 hdpu_chassis_id->proc_fops = &proc_chassis_id;
 120                 hdpu_chassis_id->owner = THIS_MODULE;
 121         }
 122
 123         return 0;
 124 }
 125
 126 static int hdpu_nexus_remove(struct platform_device *pdev)
 127 {
 128         slot_id = -1;
 129         chassis_id = -1;
 130
 131         remove_proc_entry("sky_slot_id", &proc_root);
 132         remove_proc_entry("sky_chassis_id", &proc_root);
 133
 134         hdpu_slot_id = 0;
 135         hdpu_chassis_id = 0;
 136
 137         return 0;
 138 }
 139
 140 static int __init nexus_init(void)
 141 {
 142         return platform_driver_register(&hdpu_nexus_driver);
 143 }
 144
 145 static void __exit nexus_exit(void)
 146 {
 147         platform_driver_unregister(&hdpu_nexus_driver);
 148 }
 149
 150 module_init(nexus_init);
 151 module_exit(nexus_exit);
 152
 153 MODULE_AUTHOR("Brian Waite");
 154 MODULE_LICENSE("GPL");
 155 MODULE_ALIAS("platform:" HDPU_NEXUS_NAME);