drivers/isdn/gigaset/proc.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Stuff used by all variants of the driver
   4  *
   5  * Copyright (c) 2001 by Stefan Eilers,
   6  *                       Hansjoerg Lipp <hjlipp@web.de>,
   7  *                       Tilman Schmidt <tilman@imap.cc>.
   8  *
   9  * =====================================================================
  10  * =====================================================================
  11  */
  12
  13 #include "gigaset.h"
  14
  15 static ssize_t show_cidmode(struct device *dev,
  16                             struct device_attribute *attr, char *buf)
  17 {
  18         struct cardstate *cs = dev_get_drvdata(dev);
  19
  20         return sprintf(buf, "%u\n", cs->cidmode);
  21 }
  22
  23 static ssize_t set_cidmode(struct device *dev, struct device_attribute *attr,
  24                            const char *buf, size_t count)
  25 {
  26         struct cardstate *cs = dev_get_drvdata(dev);
  27         long int value;
  28         char *end;
  29
  30         value = simple_strtol(buf, &end, 0);
  31         while (*end)
  32                 if (!isspace(*end++))
  33                         return -EINVAL;
  34         if (value < 0 || value > 1)
  35                 return -EINVAL;
  36
  37         if (mutex_lock_interruptible(&cs->mutex))
  38                 return -ERESTARTSYS;
  39
  40         cs->waiting = 1;
  41         if (!gigaset_add_event(cs, &cs->at_state, EV_PROC_CIDMODE,
  42                                NULL, value, NULL)) {
  43                 cs->waiting = 0;
  44                 mutex_unlock(&cs->mutex);
  45                 return -ENOMEM;
  46         }
  47         gigaset_schedule_event(cs);
  48
  49         wait_event(cs->waitqueue, !cs->waiting);
  50
  51         mutex_unlock(&cs->mutex);
  52
  53         return count;
  54 }
  55
  56 static DEVICE_ATTR(cidmode, S_IRUGO | S_IWUSR, show_cidmode, set_cidmode);
  57
  58 /* free sysfs for device */
  59 void gigaset_free_dev_sysfs(struct cardstate *cs)
  60 {
  61         if (!cs->tty_dev)
  62                 return;
  63
  64         gig_dbg(DEBUG_INIT, "removing sysfs entries");
  65         device_remove_file(cs->tty_dev, &dev_attr_cidmode);
  66 }
  67
  68 /* initialize sysfs for device */
  69 void gigaset_init_dev_sysfs(struct cardstate *cs)
  70 {
  71         if (!cs->tty_dev)
  72                 return;
  73
  74         gig_dbg(DEBUG_INIT, "setting up sysfs");
  75         if (device_create_file(cs->tty_dev, &dev_attr_cidmode))
  76                 pr_err("could not create sysfs attribute\n");
  77 }