drivers/staging/comedi/proc.c

   1 /*
   2  * /proc interface for comedi
   3  *
   4  * COMEDI - Linux Control and Measurement Device Interface
   5  * Copyright (C) 1998 David A. Schleef <ds@schleef.org>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  */
  17
  18 /*
  19  * This is some serious bloatware.
  20  *
  21  * Taken from Dave A.'s PCL-711 driver, 'cuz I thought it
  22  * was cool.
  23  */
  24
  25 #include "comedidev.h"
  26 #include "comedi_internal.h"
  27 #include <linux/proc_fs.h>
  28 #include <linux/seq_file.h>
  29
  30 static int comedi_read(struct seq_file *m, void *v)
  31 {
  32         int i;
  33         int devices_q = 0;
  34         struct comedi_driver *driv;
  35
  36         seq_printf(m, "comedi version " COMEDI_RELEASE "\nformat string: %s\n",
  37                    "\"%2d: %-20s %-20s %4d\", i, driver_name, board_name, n_subdevices");
  38
  39         for (i = 0; i < COMEDI_NUM_BOARD_MINORS; i++) {
  40                 struct comedi_device *dev = comedi_dev_get_from_minor(i);
  41
  42                 if (!dev)
  43                         continue;
  44
  45                 down_read(&dev->attach_lock);
  46                 if (dev->attached) {
  47                         devices_q = 1;
  48                         seq_printf(m, "%2d: %-20s %-20s %4d\n",
  49                                    i, dev->driver->driver_name,
  50                                    dev->board_name, dev->n_subdevices);
  51                 }
  52                 up_read(&dev->attach_lock);
  53                 comedi_dev_put(dev);
  54         }
  55         if (!devices_q)
  56                 seq_puts(m, "no devices\n");
  57
  58         mutex_lock(&comedi_drivers_list_lock);
  59         for (driv = comedi_drivers; driv; driv = driv->next) {
  60                 seq_printf(m, "%s:\n", driv->driver_name);
  61                 for (i = 0; i < driv->num_names; i++)
  62                         seq_printf(m, " %s\n",
  63                                    *(char **)((char *)driv->board_name +
  64                                               i * driv->offset));
  65
  66                 if (!driv->num_names)
  67                         seq_printf(m, " %s\n", driv->driver_name);
  68         }
  69         mutex_unlock(&comedi_drivers_list_lock);
  70
  71         return 0;
  72 }
  73
  74 /*
  75  * seq_file wrappers for procfile show routines.
  76  */
  77 static int comedi_proc_open(struct inode *inode, struct file *file)
  78 {
  79         return single_open(file, comedi_read, NULL);
  80 }
  81
  82 static const struct file_operations comedi_proc_fops = {
  83         .owner          = THIS_MODULE,
  84         .open           = comedi_proc_open,
  85         .read           = seq_read,
  86         .llseek         = seq_lseek,
  87         .release        = single_release,
  88 };
  89
  90 void __init comedi_proc_init(void)
  91 {
  92         if (!proc_create("comedi", 0444, NULL, &comedi_proc_fops))
  93                 pr_warn("comedi: unable to create proc entry\n");
  94 }
  95
  96 void comedi_proc_cleanup(void)
  97 {
  98         remove_proc_entry("comedi", NULL);
  99 }