sound/pci/hda/hda_hwdep.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * HWDEP Interface for HD-audio codec
   4  *
   5  * Copyright (c) 2007 Takashi Iwai <tiwai@suse.de>
   6  */
   7
   8 #include <linux/init.h>
   9 #include <linux/slab.h>
  10 #include <linux/compat.h>
  11 #include <linux/nospec.h>
  12 #include <sound/core.h>
  13 #include <sound/hda_codec.h>
  14 #include "hda_local.h"
  15 #include <sound/hda_hwdep.h>
  16 #include <sound/minors.h>
  17
  18 /*
  19  * write/read an out-of-bound verb
  20  */
  21 static int verb_write_ioctl(struct hda_codec *codec,
  22                             struct hda_verb_ioctl __user *arg)
  23 {
  24         u32 verb, res;
  25
  26         if (get_user(verb, &arg->verb))
  27                 return -EFAULT;
  28         res = snd_hda_codec_read(codec, verb >> 24, 0,
  29                                  (verb >> 8) & 0xffff, verb & 0xff);
  30         if (put_user(res, &arg->res))
  31                 return -EFAULT;
  32         return 0;
  33 }
  34
  35 static int get_wcap_ioctl(struct hda_codec *codec,
  36                           struct hda_verb_ioctl __user *arg)
  37 {
  38         u32 verb, res;
  39
  40         if (get_user(verb, &arg->verb))
  41                 return -EFAULT;
  42         /* open-code get_wcaps(verb>>24) with nospec */
  43         verb >>= 24;
  44         if (verb < codec->core.start_nid ||
  45             verb >= codec->core.start_nid + codec->core.num_nodes) {
  46                 res = 0;
  47         } else {
  48                 verb -= codec->core.start_nid;
  49                 verb = array_index_nospec(verb, codec->core.num_nodes);
  50                 res = codec->wcaps[verb];
  51         }
  52         if (put_user(res, &arg->res))
  53                 return -EFAULT;
  54         return 0;
  55 }
  56
  57
  58 /*
  59  */
  60 static int hda_hwdep_ioctl(struct snd_hwdep *hw, struct file *file,
  61                            unsigned int cmd, unsigned long arg)
  62 {
  63         struct hda_codec *codec = hw->private_data;
  64         void __user *argp = (void __user *)arg;
  65
  66         switch (cmd) {
  67         case HDA_IOCTL_PVERSION:
  68                 return put_user(HDA_HWDEP_VERSION, (int __user *)argp);
  69         case HDA_IOCTL_VERB_WRITE:
  70                 return verb_write_ioctl(codec, argp);
  71         case HDA_IOCTL_GET_WCAP:
  72                 return get_wcap_ioctl(codec, argp);
  73         }
  74         return -ENOIOCTLCMD;
  75 }
  76
  77 #ifdef CONFIG_COMPAT
  78 static int hda_hwdep_ioctl_compat(struct snd_hwdep *hw, struct file *file,
  79                                   unsigned int cmd, unsigned long arg)
  80 {
  81         return hda_hwdep_ioctl(hw, file, cmd, (unsigned long)compat_ptr(arg));
  82 }
  83 #endif
  84
  85 static int hda_hwdep_open(struct snd_hwdep *hw, struct file *file)
  86 {
  87 #ifndef CONFIG_SND_DEBUG_VERBOSE
  88         if (!capable(CAP_SYS_RAWIO))
  89                 return -EACCES;
  90 #endif
  91         return 0;
  92 }
  93
  94 int snd_hda_create_hwdep(struct hda_codec *codec)
  95 {
  96         char hwname[16];
  97         struct snd_hwdep *hwdep;
  98         int err;
  99
 100         sprintf(hwname, "HDA Codec %d", codec->addr);
 101         err = snd_hwdep_new(codec->card, hwname, codec->addr, &hwdep);
 102         if (err < 0)
 103                 return err;
 104         codec->hwdep = hwdep;
 105         sprintf(hwdep->name, "HDA Codec %d", codec->addr);
 106         hwdep->iface = SNDRV_HWDEP_IFACE_HDA;
 107         hwdep->private_data = codec;
 108         hwdep->exclusive = 1;
 109
 110         hwdep->ops.open = hda_hwdep_open;
 111         hwdep->ops.ioctl = hda_hwdep_ioctl;
 112 #ifdef CONFIG_COMPAT
 113         hwdep->ops.ioctl_compat = hda_hwdep_ioctl_compat;
 114 #endif
 115
 116         /* for sysfs */
 117         hwdep->dev->groups = snd_hda_dev_attr_groups;
 118         dev_set_drvdata(hwdep->dev, codec);
 119
 120         return 0;
 121 }