sound/pci/hda/hda_hwdep.c

   1 /*
   2  * HWDEP Interface for HD-audio codec
   3  *
   4  * Copyright (c) 2007 Takashi Iwai <tiwai@suse.de>
   5  *
   6  *  This driver is free software; you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation; either version 2 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  This driver is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with this program; if not, write to the Free Software
  18  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  19  */
  20
  21 #include <linux/init.h>
  22 #include <linux/slab.h>
  23 #include <linux/compat.h>
  24 #include <linux/nospec.h>
  25 #include <sound/core.h>
  26 #include "hda_codec.h"
  27 #include "hda_local.h"
  28 #include <sound/hda_hwdep.h>
  29 #include <sound/minors.h>
  30
  31 /*
  32  * write/read an out-of-bound verb
  33  */
  34 static int verb_write_ioctl(struct hda_codec *codec,
  35                             struct hda_verb_ioctl __user *arg)
  36 {
  37         u32 verb, res;
  38
  39         if (get_user(verb, &arg->verb))
  40                 return -EFAULT;
  41         res = snd_hda_codec_read(codec, verb >> 24, 0,
  42                                  (verb >> 8) & 0xffff, verb & 0xff);
  43         if (put_user(res, &arg->res))
  44                 return -EFAULT;
  45         return 0;
  46 }
  47
  48 static int get_wcap_ioctl(struct hda_codec *codec,
  49                           struct hda_verb_ioctl __user *arg)
  50 {
  51         u32 verb, res;
  52
  53         if (get_user(verb, &arg->verb))
  54                 return -EFAULT;
  55         /* open-code get_wcaps(verb>>24) with nospec */
  56         verb >>= 24;
  57         if (verb < codec->core.start_nid ||
  58             verb >= codec->core.start_nid + codec->core.num_nodes) {
  59                 res = 0;
  60         } else {
  61                 verb -= codec->core.start_nid;
  62                 verb = array_index_nospec(verb, codec->core.num_nodes);
  63                 res = codec->wcaps[verb];
  64         }
  65         if (put_user(res, &arg->res))
  66                 return -EFAULT;
  67         return 0;
  68 }
  69
  70
  71 /*
  72  */
  73 static int hda_hwdep_ioctl(struct snd_hwdep *hw, struct file *file,
  74                            unsigned int cmd, unsigned long arg)
  75 {
  76         struct hda_codec *codec = hw->private_data;
  77         void __user *argp = (void __user *)arg;
  78
  79         switch (cmd) {
  80         case HDA_IOCTL_PVERSION:
  81                 return put_user(HDA_HWDEP_VERSION, (int __user *)argp);
  82         case HDA_IOCTL_VERB_WRITE:
  83                 return verb_write_ioctl(codec, argp);
  84         case HDA_IOCTL_GET_WCAP:
  85                 return get_wcap_ioctl(codec, argp);
  86         }
  87         return -ENOIOCTLCMD;
  88 }
  89
  90 #ifdef CONFIG_COMPAT
  91 static int hda_hwdep_ioctl_compat(struct snd_hwdep *hw, struct file *file,
  92                                   unsigned int cmd, unsigned long arg)
  93 {
  94         return hda_hwdep_ioctl(hw, file, cmd, (unsigned long)compat_ptr(arg));
  95 }
  96 #endif
  97
  98 static int hda_hwdep_open(struct snd_hwdep *hw, struct file *file)
  99 {
 100 #ifndef CONFIG_SND_DEBUG_VERBOSE
 101         if (!capable(CAP_SYS_RAWIO))
 102                 return -EACCES;
 103 #endif
 104         return 0;
 105 }
 106
 107 int snd_hda_create_hwdep(struct hda_codec *codec)
 108 {
 109         char hwname[16];
 110         struct snd_hwdep *hwdep;
 111         int err;
 112
 113         sprintf(hwname, "HDA Codec %d", codec->addr);
 114         err = snd_hwdep_new(codec->card, hwname, codec->addr, &hwdep);
 115         if (err < 0)
 116                 return err;
 117         codec->hwdep = hwdep;
 118         sprintf(hwdep->name, "HDA Codec %d", codec->addr);
 119         hwdep->iface = SNDRV_HWDEP_IFACE_HDA;
 120         hwdep->private_data = codec;
 121         hwdep->exclusive = 1;
 122
 123         hwdep->ops.open = hda_hwdep_open;
 124         hwdep->ops.ioctl = hda_hwdep_ioctl;
 125 #ifdef CONFIG_COMPAT
 126         hwdep->ops.ioctl_compat = hda_hwdep_ioctl_compat;
 127 #endif
 128
 129         /* for sysfs */
 130         hwdep->dev.groups = snd_hda_dev_attr_groups;
 131         dev_set_drvdata(&hwdep->dev, codec);
 132
 133         return 0;
 134 }