LXR linux/drivers/staging/comedi/proc.c

   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * /proc interface for comedi
   4 *
   5 * COMEDI - Linux Control and Measurement Device Interface
   6 * Copyright (C) 1998 David A. Schleef <ds@schleef.org>
   7 */
   8
   9/*
  10 * This is some serious bloatware.
  11 *
  12 * Taken from Dave A.'s PCL-711 driver, 'cuz I thought it
  13 * was cool.
  14 */
  15
  16#include "comedidev.h"
  17#include "comedi_internal.h"
  18#include <linux/proc_fs.h>
  19#include <linux/seq_file.h>
  20
  21static int comedi_read(struct seq_file *m, void *v)
  22{
  23        int i;
  24        int devices_q = 0;
  25        struct comedi_driver *driv;
  26
  27        seq_printf(m, "comedi version " COMEDI_RELEASE "\nformat string: %s\n",
  28                   "\"%2d: %-20s %-20s %4d\", i, driver_name, board_name, n_subdevices");
  29
  30        for (i = 0; i < COMEDI_NUM_BOARD_MINORS; i++) {
  31                struct comedi_device *dev = comedi_dev_get_from_minor(i);
  32
  33                if (!dev)
  34                        continue;
  35
  36                down_read(&dev->attach_lock);
  37                if (dev->attached) {
  38                        devices_q = 1;
  39                        seq_printf(m, "%2d: %-20s %-20s %4d\n",
  40                                   i, dev->driver->driver_name,
  41                                   dev->board_name, dev->n_subdevices);
  42                }
  43                up_read(&dev->attach_lock);
  44                comedi_dev_put(dev);
  45        }
  46        if (!devices_q)
  47                seq_puts(m, "no devices\n");
  48
  49        mutex_lock(&comedi_drivers_list_lock);
  50        for (driv = comedi_drivers; driv; driv = driv->next) {
  51                seq_printf(m, "%s:\n", driv->driver_name);
  52                for (i = 0; i < driv->num_names; i++)
  53                        seq_printf(m, " %s\n",
  54                                   *(char **)((char *)driv->board_name +
  55                                              i * driv->offset));
  56
  57                if (!driv->num_names)
  58                        seq_printf(m, " %s\n", driv->driver_name);
  59        }
  60        mutex_unlock(&comedi_drivers_list_lock);
  61
  62        return 0;
  63}
  64
  65/*
  66 * seq_file wrappers for procfile show routines.
  67 */
  68static int comedi_proc_open(struct inode *inode, struct file *file)
  69{
  70        return single_open(file, comedi_read, NULL);
  71}
  72
  73static const struct file_operations comedi_proc_fops = {
  74        .owner          = THIS_MODULE,
  75        .open           = comedi_proc_open,
  76        .read           = seq_read,
  77        .llseek         = seq_lseek,
  78        .release        = single_release,
  79};
  80
  81void __init comedi_proc_init(void)
  82{
  83        if (!proc_create("comedi", 0444, NULL, &comedi_proc_fops))
  84                pr_warn("comedi: unable to create proc entry\n");
  85}
  86
  87void comedi_proc_cleanup(void)
  88{
  89        remove_proc_entry("comedi", NULL);
  90}
  91