diff mbox

sound: hdmi: avoid dereferencing uninitialized 'jack' pointer

Message ID s5h8u2j6749.wl-tiwai@suse.de (mailing list archive)
State New, archived
Headers show

Commit Message

Takashi Iwai Feb. 17, 2016, 9:03 a.m. UTC
On Tue, 16 Feb 2016 23:08:13 +0100,
Arnd Bergmann wrote:
> 
> On Tuesday 16 February 2016 18:26:09 Arnd Bergmann wrote:
> > >                 return err;
> > >         per_pin->acomp_jack = jack;
> > > -       jack->private_data = per_pin;
> > > -       jack->private_free = free_acomp_jack_priv;
> > > +       if (jack) {
> > > +               jack->private_data = per_pin;
> > > +               jack->private_free = free_acomp_jack_priv;
> > > +       }
> > >         return 0;
> > >  }
> > > 
> > Looks good to me.
> > 
> > Acked-by: Arnd Bergmann <arnd@arndb.de>
> > 
> 
> Actually, on second thought, there is one notable downside
> of this approach: 'jack' is guaranteed to be NULL here, so gcc
> won't produce a warning if another driver makes the same mistake:
> 
> By default, we only get a warning for uses of uninitialized
> variables, but not those that are known to be NULL. I think
> some compiler warnings are able to warn about that too, but I
> forgot the details.

Yes, that is a good point.

On third thought, we should look back how this issue came out.

Originally HD-audio driver had another jack implementation using ctl
API, and this could be unconditionally enabled.  The kctl jack was
unified into the input jack layer later, and the dependency issue came
out.  In that sense, the problem is that SND_JACK dependency is still
present although it's not needed -- namely, the jack layer itself can
be implemented in kctl even without input devices.

So, the missing piece is the conditional build of jack.c & co without
CONFIG_INPUT.  Then the dependency in the user's side can be ignored.

Below is the patch to do that.


Takashi

-- 8< --
From: Takashi Iwai <tiwai@suse.de>
Subject: [PATCH] ALSA: jack: Allow building the jack layer without input
 device

Since the recent integration of kctl jack and input jack layers, we
can basically build the jack layer even without input devices.  That
is, the jack layer itself can be built with conditional to enable the
input device support or not, while the users may enable always
CONFIG_SND_JACK unconditionally.

For achieving it, this patch changes the following:
- A new Kconfig, CONFIG_SND_JACK_INPUT_DEV, was introduced to indicate
  whether the jack layer supports the input device,
- A few items in snd_jack struct and relevant codes are conditionally
  built upon CONFIG_SND_JACK_INPUT_DEV,
- The users of CONFIG_SND_JACK drop the messy dependency on
  CONFIG_INPUT, but just select SND_JACK.

This change also automagically fixes a potential bug in HD-audio
driver Arnd reported, where the NULL or uninitialized jack instance is
dereferenced.

Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
---
 include/sound/jack.h  | 23 ++++++++++++++---------
 sound/core/Kconfig    |  9 ++++++---
 sound/core/jack.c     | 23 ++++++++++++++++++++---
 sound/pci/Kconfig     |  2 +-
 sound/pci/hda/Kconfig |  2 +-
 sound/soc/Kconfig     |  2 +-
 6 files changed, 43 insertions(+), 18 deletions(-)

Comments

kernel test robot Feb. 17, 2016, 9:24 a.m. UTC | #1
Hi Takashi,

[auto build test ERROR on sound/for-next]
[also build test ERROR on v4.5-rc4 next-20160217]
[if your patch is applied to the wrong git tree, please drop us a note to help improving the system]

url:    https://github.com/0day-ci/linux/commits/Takashi-Iwai/ALSA-jack-Allow-building-the-jack-layer-without-input/20160217-171209
base:   https://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound.git for-next
config: x86_64-randconfig-x012-201607 (attached as .config)
reproduce:
        # save the attached .config to linux build tree
        make ARCH=x86_64 

All errors (new ones prefixed by >>):

>> sound/core/jack.c:184:5: error: redefinition of 'snd_jack_add_new_kctl'
    int snd_jack_add_new_kctl(struct snd_jack *jack, const char * name, int mask)
        ^
   In file included from sound/core/jack.c:25:0:
   include/sound/jack.h:108:19: note: previous definition of 'snd_jack_add_new_kctl' was here
    static inline int snd_jack_add_new_kctl(struct snd_jack *jack, const char * name, int mask)
                      ^
>> sound/core/jack.c:212:5: error: redefinition of 'snd_jack_new'
    int snd_jack_new(struct snd_card *card, const char *id, int type,
        ^
   In file included from sound/core/jack.c:25:0:
   include/sound/jack.h:102:19: note: previous definition of 'snd_jack_new' was here
    static inline int snd_jack_new(struct snd_card *card, const char *id, int type,
                      ^
>> sound/core/jack.c:296:6: error: redefinition of 'snd_jack_set_parent'
    void snd_jack_set_parent(struct snd_jack *jack, struct device *parent)
         ^
   In file included from sound/core/jack.c:25:0:
   include/sound/jack.h:120:20: note: previous definition of 'snd_jack_set_parent' was here
    static inline void snd_jack_set_parent(struct snd_jack *jack,
                       ^
>> sound/core/jack.c:331:5: error: redefinition of 'snd_jack_set_key'
    int snd_jack_set_key(struct snd_jack *jack, enum snd_jack_types type,
        ^
   In file included from sound/core/jack.c:25:0:
   include/sound/jack.h:125:19: note: previous definition of 'snd_jack_set_key' was here
    static inline int snd_jack_set_key(struct snd_jack *jack,
                      ^
>> sound/core/jack.c:354:6: error: redefinition of 'snd_jack_report'
    void snd_jack_report(struct snd_jack *jack, int status)
         ^
   In file included from sound/core/jack.c:25:0:
   include/sound/jack.h:113:20: note: previous definition of 'snd_jack_report' was here
    static inline void snd_jack_report(struct snd_jack *jack, int status)
                       ^

vim +/snd_jack_add_new_kctl +184 sound/core/jack.c

9058cbe1e Jie Yang         2015-04-27  178   *         by this snd_jack_kctl object.
9058cbe1e Jie Yang         2015-04-27  179   *
9058cbe1e Jie Yang         2015-04-27  180   * Creates a new snd_kcontrol object and adds it to the jack kctl_list.
9058cbe1e Jie Yang         2015-04-27  181   *
9058cbe1e Jie Yang         2015-04-27  182   * Return: Zero if successful, or a negative error code on failure.
9058cbe1e Jie Yang         2015-04-27  183   */
9058cbe1e Jie Yang         2015-04-27 @184  int snd_jack_add_new_kctl(struct snd_jack *jack, const char * name, int mask)
9058cbe1e Jie Yang         2015-04-27  185  {
9058cbe1e Jie Yang         2015-04-27  186  	struct snd_jack_kctl *jack_kctl;
9058cbe1e Jie Yang         2015-04-27  187  
9058cbe1e Jie Yang         2015-04-27  188  	jack_kctl = snd_jack_kctl_new(jack->card, name, mask);
9058cbe1e Jie Yang         2015-04-27  189  	if (!jack_kctl)
9058cbe1e Jie Yang         2015-04-27  190  		return -ENOMEM;
9058cbe1e Jie Yang         2015-04-27  191  
9058cbe1e Jie Yang         2015-04-27  192  	snd_jack_kctl_add(jack, jack_kctl);
9058cbe1e Jie Yang         2015-04-27  193  	return 0;
9058cbe1e Jie Yang         2015-04-27  194  }
9058cbe1e Jie Yang         2015-04-27  195  EXPORT_SYMBOL(snd_jack_add_new_kctl);
9058cbe1e Jie Yang         2015-04-27  196  
e76d8ceaa Mark Brown       2008-07-28  197  /**
e76d8ceaa Mark Brown       2008-07-28  198   * snd_jack_new - Create a new jack
e76d8ceaa Mark Brown       2008-07-28  199   * @card:  the card instance
e76d8ceaa Mark Brown       2008-07-28  200   * @id:    an identifying string for this jack
e76d8ceaa Mark Brown       2008-07-28  201   * @type:  a bitmask of enum snd_jack_type values that can be detected by
e76d8ceaa Mark Brown       2008-07-28  202   *         this jack
e76d8ceaa Mark Brown       2008-07-28  203   * @jjack: Used to provide the allocated jack object to the caller.
4e3f0dc65 Jie Yang         2015-04-27  204   * @initial_kctl: if true, create a kcontrol and add it to the jack list.
4e3f0dc65 Jie Yang         2015-04-27  205   * @phantom_jack: Don't create a input device for phantom jacks.
e76d8ceaa Mark Brown       2008-07-28  206   *
e76d8ceaa Mark Brown       2008-07-28  207   * Creates a new jack object.
e76d8ceaa Mark Brown       2008-07-28  208   *
eb7c06e8e Yacine Belkadi   2013-03-11  209   * Return: Zero if successful, or a negative error code on failure.
eb7c06e8e Yacine Belkadi   2013-03-11  210   * On success @jjack will be initialised.
e76d8ceaa Mark Brown       2008-07-28  211   */
e76d8ceaa Mark Brown       2008-07-28 @212  int snd_jack_new(struct snd_card *card, const char *id, int type,
4e3f0dc65 Jie Yang         2015-04-27  213  		 struct snd_jack **jjack, bool initial_kctl, bool phantom_jack)
e76d8ceaa Mark Brown       2008-07-28  214  {
e76d8ceaa Mark Brown       2008-07-28  215  	struct snd_jack *jack;
4e3f0dc65 Jie Yang         2015-04-27  216  	struct snd_jack_kctl *jack_kctl = NULL;
e76d8ceaa Mark Brown       2008-07-28  217  	int err;
e76d8ceaa Mark Brown       2008-07-28  218  	static struct snd_device_ops ops = {
e76d8ceaa Mark Brown       2008-07-28  219  		.dev_free = snd_jack_dev_free,
dbe821f46 Takashi Iwai     2016-02-17  220  #ifdef CONFIG_SND_JACK_INPUT_DEV
e76d8ceaa Mark Brown       2008-07-28  221  		.dev_register = snd_jack_dev_register,
32b854429 Takashi Iwai     2013-11-14  222  		.dev_disconnect = snd_jack_dev_disconnect,
dbe821f46 Takashi Iwai     2016-02-17  223  #endif /* CONFIG_SND_JACK_INPUT_DEV */
e76d8ceaa Mark Brown       2008-07-28  224  	};
e76d8ceaa Mark Brown       2008-07-28  225  
4e3f0dc65 Jie Yang         2015-04-27  226  	if (initial_kctl) {
4e3f0dc65 Jie Yang         2015-04-27  227  		jack_kctl = snd_jack_kctl_new(card, id, type);
4e3f0dc65 Jie Yang         2015-04-27  228  		if (!jack_kctl)
4e3f0dc65 Jie Yang         2015-04-27  229  			return -ENOMEM;
4e3f0dc65 Jie Yang         2015-04-27  230  	}
4e3f0dc65 Jie Yang         2015-04-27  231  
e76d8ceaa Mark Brown       2008-07-28  232  	jack = kzalloc(sizeof(struct snd_jack), GFP_KERNEL);
e76d8ceaa Mark Brown       2008-07-28  233  	if (jack == NULL)
e76d8ceaa Mark Brown       2008-07-28  234  		return -ENOMEM;
e76d8ceaa Mark Brown       2008-07-28  235  
282cd76ff Matthew Ranostay 2008-10-25  236  	jack->id = kstrdup(id, GFP_KERNEL);
e76d8ceaa Mark Brown       2008-07-28  237  
4e3f0dc65 Jie Yang         2015-04-27  238  	/* don't creat input device for phantom jack */
4e3f0dc65 Jie Yang         2015-04-27  239  	if (!phantom_jack) {
dbe821f46 Takashi Iwai     2016-02-17  240  #ifdef CONFIG_SND_JACK_INPUT_DEV
dbe821f46 Takashi Iwai     2016-02-17  241  		int i;
dbe821f46 Takashi Iwai     2016-02-17  242  
e76d8ceaa Mark Brown       2008-07-28  243  		jack->input_dev = input_allocate_device();
e76d8ceaa Mark Brown       2008-07-28  244  		if (jack->input_dev == NULL) {
e76d8ceaa Mark Brown       2008-07-28  245  			err = -ENOMEM;
e76d8ceaa Mark Brown       2008-07-28  246  			goto fail_input;
e76d8ceaa Mark Brown       2008-07-28  247  		}
e76d8ceaa Mark Brown       2008-07-28  248  
e76d8ceaa Mark Brown       2008-07-28  249  		jack->input_dev->phys = "ALSA";
e76d8ceaa Mark Brown       2008-07-28  250  
e76d8ceaa Mark Brown       2008-07-28  251  		jack->type = type;
e76d8ceaa Mark Brown       2008-07-28  252  
53803aead Mark Brown       2012-02-07  253  		for (i = 0; i < SND_JACK_SWITCH_TYPES; i++)
bd8a71a7b Mark Brown       2009-01-03  254  			if (type & (1 << i))
e76d8ceaa Mark Brown       2008-07-28  255  				input_set_capability(jack->input_dev, EV_SW,
1c6e555c3 Mark Brown       2010-03-17  256  						     jack_switch_types[i]);
e76d8ceaa Mark Brown       2008-07-28  257  
dbe821f46 Takashi Iwai     2016-02-17  258  #endif /* CONFIG_SND_JACK_INPUT_DEV */
4e3f0dc65 Jie Yang         2015-04-27  259  	}
4e3f0dc65 Jie Yang         2015-04-27  260  
e76d8ceaa Mark Brown       2008-07-28  261  	err = snd_device_new(card, SNDRV_DEV_JACK, jack, &ops);
e76d8ceaa Mark Brown       2008-07-28  262  	if (err < 0)
e76d8ceaa Mark Brown       2008-07-28  263  		goto fail_input;
e76d8ceaa Mark Brown       2008-07-28  264  
9058cbe1e Jie Yang         2015-04-27  265  	jack->card = card;
9058cbe1e Jie Yang         2015-04-27  266  	INIT_LIST_HEAD(&jack->kctl_list);
9058cbe1e Jie Yang         2015-04-27  267  
4e3f0dc65 Jie Yang         2015-04-27  268  	if (initial_kctl)
4e3f0dc65 Jie Yang         2015-04-27  269  		snd_jack_kctl_add(jack, jack_kctl);
4e3f0dc65 Jie Yang         2015-04-27  270  
e76d8ceaa Mark Brown       2008-07-28  271  	*jjack = jack;
e76d8ceaa Mark Brown       2008-07-28  272  
e76d8ceaa Mark Brown       2008-07-28  273  	return 0;
e76d8ceaa Mark Brown       2008-07-28  274  
e76d8ceaa Mark Brown       2008-07-28  275  fail_input:
dbe821f46 Takashi Iwai     2016-02-17  276  #ifdef CONFIG_SND_JACK_INPUT_DEV
e76d8ceaa Mark Brown       2008-07-28  277  	input_free_device(jack->input_dev);
dbe821f46 Takashi Iwai     2016-02-17  278  #endif
eeda276be Lu Guanqun       2011-02-21  279  	kfree(jack->id);
e76d8ceaa Mark Brown       2008-07-28  280  	kfree(jack);
e76d8ceaa Mark Brown       2008-07-28  281  	return err;
e76d8ceaa Mark Brown       2008-07-28  282  }
e76d8ceaa Mark Brown       2008-07-28  283  EXPORT_SYMBOL(snd_jack_new);
e76d8ceaa Mark Brown       2008-07-28  284  
dbe821f46 Takashi Iwai     2016-02-17  285  #ifdef CONFIG_SND_JACK_INPUT_DEV
e76d8ceaa Mark Brown       2008-07-28  286  /**
e76d8ceaa Mark Brown       2008-07-28  287   * snd_jack_set_parent - Set the parent device for a jack
e76d8ceaa Mark Brown       2008-07-28  288   *
e76d8ceaa Mark Brown       2008-07-28  289   * @jack:   The jack to configure
e76d8ceaa Mark Brown       2008-07-28  290   * @parent: The device to set as parent for the jack.
e76d8ceaa Mark Brown       2008-07-28  291   *
a2e888f0d Mark Brown       2012-05-07  292   * Set the parent for the jack devices in the device tree.  This
e76d8ceaa Mark Brown       2008-07-28  293   * function is only valid prior to registration of the jack.  If no
e76d8ceaa Mark Brown       2008-07-28  294   * parent is configured then the parent device will be the sound card.
e76d8ceaa Mark Brown       2008-07-28  295   */
e76d8ceaa Mark Brown       2008-07-28 @296  void snd_jack_set_parent(struct snd_jack *jack, struct device *parent)
e76d8ceaa Mark Brown       2008-07-28  297  {
e76d8ceaa Mark Brown       2008-07-28  298  	WARN_ON(jack->registered);
43b2cd547 Takashi Iwai     2015-04-30  299  	if (!jack->input_dev)
43b2cd547 Takashi Iwai     2015-04-30  300  		return;
e76d8ceaa Mark Brown       2008-07-28  301  
e76d8ceaa Mark Brown       2008-07-28  302  	jack->input_dev->dev.parent = parent;
e76d8ceaa Mark Brown       2008-07-28  303  }
e76d8ceaa Mark Brown       2008-07-28  304  EXPORT_SYMBOL(snd_jack_set_parent);
e76d8ceaa Mark Brown       2008-07-28  305  
e76d8ceaa Mark Brown       2008-07-28  306  /**
ebb812cb8 Mark Brown       2010-03-17  307   * snd_jack_set_key - Set a key mapping on a jack
ebb812cb8 Mark Brown       2010-03-17  308   *
ebb812cb8 Mark Brown       2010-03-17  309   * @jack:    The jack to configure
ebb812cb8 Mark Brown       2010-03-17  310   * @type:    Jack report type for this key
ebb812cb8 Mark Brown       2010-03-17  311   * @keytype: Input layer key type to be reported
ebb812cb8 Mark Brown       2010-03-17  312   *
ebb812cb8 Mark Brown       2010-03-17  313   * Map a SND_JACK_BTN_ button type to an input layer key, allowing
ebb812cb8 Mark Brown       2010-03-17  314   * reporting of keys on accessories via the jack abstraction.  If no
ebb812cb8 Mark Brown       2010-03-17  315   * mapping is provided but keys are enabled in the jack type then
ebb812cb8 Mark Brown       2010-03-17  316   * BTN_n numeric buttons will be reported.
ebb812cb8 Mark Brown       2010-03-17  317   *
a2e888f0d Mark Brown       2012-05-07  318   * If jacks are not reporting via the input API this call will have no
a2e888f0d Mark Brown       2012-05-07  319   * effect.
a2e888f0d Mark Brown       2012-05-07  320   *
ebb812cb8 Mark Brown       2010-03-17  321   * Note that this is intended to be use by simple devices with small
ebb812cb8 Mark Brown       2010-03-17  322   * numbers of keys that can be reported.  It is also possible to
ebb812cb8 Mark Brown       2010-03-17  323   * access the input device directly - devices with complex input
ebb812cb8 Mark Brown       2010-03-17  324   * capabilities on accessories should consider doing this rather than
ebb812cb8 Mark Brown       2010-03-17  325   * using this abstraction.
ebb812cb8 Mark Brown       2010-03-17  326   *
ebb812cb8 Mark Brown       2010-03-17  327   * This function may only be called prior to registration of the jack.
eb7c06e8e Yacine Belkadi   2013-03-11  328   *
eb7c06e8e Yacine Belkadi   2013-03-11  329   * Return: Zero if successful, or a negative error code on failure.
ebb812cb8 Mark Brown       2010-03-17  330   */
ebb812cb8 Mark Brown       2010-03-17 @331  int snd_jack_set_key(struct snd_jack *jack, enum snd_jack_types type,
ebb812cb8 Mark Brown       2010-03-17  332  		     int keytype)
ebb812cb8 Mark Brown       2010-03-17  333  {
ebb812cb8 Mark Brown       2010-03-17  334  	int key = fls(SND_JACK_BTN_0) - fls(type);
ebb812cb8 Mark Brown       2010-03-17  335  
ebb812cb8 Mark Brown       2010-03-17  336  	WARN_ON(jack->registered);
ebb812cb8 Mark Brown       2010-03-17  337  
ebb812cb8 Mark Brown       2010-03-17  338  	if (!keytype || key >= ARRAY_SIZE(jack->key))
ebb812cb8 Mark Brown       2010-03-17  339  		return -EINVAL;
ebb812cb8 Mark Brown       2010-03-17  340  
ebb812cb8 Mark Brown       2010-03-17  341  	jack->type |= type;
ebb812cb8 Mark Brown       2010-03-17  342  	jack->key[key] = keytype;
ebb812cb8 Mark Brown       2010-03-17  343  	return 0;
ebb812cb8 Mark Brown       2010-03-17  344  }
ebb812cb8 Mark Brown       2010-03-17  345  EXPORT_SYMBOL(snd_jack_set_key);
dbe821f46 Takashi Iwai     2016-02-17  346  #endif /* CONFIG_SND_JACK_INPUT_DEV */
ebb812cb8 Mark Brown       2010-03-17  347  
ebb812cb8 Mark Brown       2010-03-17  348  /**
e76d8ceaa Mark Brown       2008-07-28  349   * snd_jack_report - Report the current status of a jack
e76d8ceaa Mark Brown       2008-07-28  350   *
e76d8ceaa Mark Brown       2008-07-28  351   * @jack:   The jack to report status for
e76d8ceaa Mark Brown       2008-07-28  352   * @status: The current status of the jack
e76d8ceaa Mark Brown       2008-07-28  353   */
e76d8ceaa Mark Brown       2008-07-28 @354  void snd_jack_report(struct snd_jack *jack, int status)
e76d8ceaa Mark Brown       2008-07-28  355  {
9058cbe1e Jie Yang         2015-04-27  356  	struct snd_jack_kctl *jack_kctl;
dbe821f46 Takashi Iwai     2016-02-17  357  #ifdef CONFIG_SND_JACK_INPUT_DEV

:::::: The code at line 184 was first introduced by commit
:::::: 9058cbe1eed29381f84dec9f96980f5a4ea1025f ALSA: jack: implement kctl creating for jack devices

:::::: TO: Jie Yang <yang.jie@intel.com>
:::::: CC: Takashi Iwai <tiwai@suse.de>

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation
diff mbox

Patch

diff --git a/include/sound/jack.h b/include/sound/jack.h
index 23bede121c78..1e84bfb553cf 100644
--- a/include/sound/jack.h
+++ b/include/sound/jack.h
@@ -72,14 +72,16 @@  enum snd_jack_types {
 #define SND_JACK_SWITCH_TYPES 6
 
 struct snd_jack {
-	struct input_dev *input_dev;
 	struct list_head kctl_list;
 	struct snd_card *card;
+	const char *id;
+#ifdef CONFIG_SND_JACK_INPUT_DEV
+	struct input_dev *input_dev;
 	int registered;
 	int type;
-	const char *id;
 	char name[100];
 	unsigned int key[6];   /* Keep in sync with definitions above */
+#endif /* CONFIG_SND_JACK_INPUT_DEV */
 	void *private_data;
 	void (*private_free)(struct snd_jack *);
 };
@@ -89,10 +91,11 @@  struct snd_jack {
 int snd_jack_new(struct snd_card *card, const char *id, int type,
 		 struct snd_jack **jack, bool initial_kctl, bool phantom_jack);
 int snd_jack_add_new_kctl(struct snd_jack *jack, const char * name, int mask);
+#ifdef CONFIG_SND_JACK_INPUT_DEV
 void snd_jack_set_parent(struct snd_jack *jack, struct device *parent);
 int snd_jack_set_key(struct snd_jack *jack, enum snd_jack_types type,
 		     int keytype);
-
+#endif
 void snd_jack_report(struct snd_jack *jack, int status);
 
 #else
@@ -107,6 +110,13 @@  static inline int snd_jack_add_new_kctl(struct snd_jack *jack, const char * name
 	return 0;
 }
 
+static inline void snd_jack_report(struct snd_jack *jack, int status)
+{
+}
+
+#endif
+
+#if !defined(CONFIG_SND_JACK) || !defined(CONFIG_SND_JACK_INPUT_DEV)
 static inline void snd_jack_set_parent(struct snd_jack *jack,
 				       struct device *parent)
 {
@@ -118,11 +128,6 @@  static inline int snd_jack_set_key(struct snd_jack *jack,
 {
 	return 0;
 }
-
-static inline void snd_jack_report(struct snd_jack *jack, int status)
-{
-}
-
-#endif
+#endif /* !CONFIG_SND_JACK || !CONFIG_SND_JACK_INPUT_DEV */
 
 #endif
diff --git a/sound/core/Kconfig b/sound/core/Kconfig
index a2a1e24becc6..8b71e15898cd 100644
--- a/sound/core/Kconfig
+++ b/sound/core/Kconfig
@@ -24,11 +24,14 @@  config SND_RAWMIDI
 config SND_COMPRESS_OFFLOAD
 	tristate
 
-# To be effective this also requires INPUT - users should say:
-#    select SND_JACK if INPUT=y || INPUT=SND
-# to avoid having to force INPUT on.
 config SND_JACK
+	tristate
+
+# enable input device support in jack layer
+config SND_JACK_INPUT_DEV
 	bool
+	depends on SND_JACK
+	default y if INPUT=y || INPUT=SND
 
 config SND_SEQUENCER
 	tristate "Sequencer support"
diff --git a/sound/core/jack.c b/sound/core/jack.c
index 7237acbdcbbc..f652e90efd7e 100644
--- a/sound/core/jack.c
+++ b/sound/core/jack.c
@@ -32,6 +32,7 @@  struct snd_jack_kctl {
 	unsigned int mask_bits; /* only masked status bits are reported via kctl */
 };
 
+#ifdef CONFIG_SND_JACK_INPUT_DEV
 static int jack_switch_types[SND_JACK_SWITCH_TYPES] = {
 	SW_HEADPHONE_INSERT,
 	SW_MICROPHONE_INSERT,
@@ -40,9 +41,11 @@  static int jack_switch_types[SND_JACK_SWITCH_TYPES] = {
 	SW_VIDEOOUT_INSERT,
 	SW_LINEIN_INSERT,
 };
+#endif /* CONFIG_SND_JACK_INPUT_DEV */
 
 static int snd_jack_dev_disconnect(struct snd_device *device)
 {
+#ifdef CONFIG_SND_JACK_INPUT_DEV
 	struct snd_jack *jack = device->device_data;
 
 	if (!jack->input_dev)
@@ -55,6 +58,7 @@  static int snd_jack_dev_disconnect(struct snd_device *device)
 	else
 		input_free_device(jack->input_dev);
 	jack->input_dev = NULL;
+#endif /* CONFIG_SND_JACK_INPUT_DEV */
 	return 0;
 }
 
@@ -79,6 +83,7 @@  static int snd_jack_dev_free(struct snd_device *device)
 	return 0;
 }
 
+#ifdef CONFIG_SND_JACK_INPUT_DEV
 static int snd_jack_dev_register(struct snd_device *device)
 {
 	struct snd_jack *jack = device->device_data;
@@ -116,6 +121,7 @@  static int snd_jack_dev_register(struct snd_device *device)
 
 	return err;
 }
+#endif /* CONFIG_SND_JACK_INPUT_DEV */
 
 static void snd_jack_kctl_private_free(struct snd_kcontrol *kctl)
 {
@@ -209,11 +215,12 @@  int snd_jack_new(struct snd_card *card, const char *id, int type,
 	struct snd_jack *jack;
 	struct snd_jack_kctl *jack_kctl = NULL;
 	int err;
-	int i;
 	static struct snd_device_ops ops = {
 		.dev_free = snd_jack_dev_free,
+#ifdef CONFIG_SND_JACK_INPUT_DEV
 		.dev_register = snd_jack_dev_register,
 		.dev_disconnect = snd_jack_dev_disconnect,
+#endif /* CONFIG_SND_JACK_INPUT_DEV */
 	};
 
 	if (initial_kctl) {
@@ -230,6 +237,9 @@  int snd_jack_new(struct snd_card *card, const char *id, int type,
 
 	/* don't creat input device for phantom jack */
 	if (!phantom_jack) {
+#ifdef CONFIG_SND_JACK_INPUT_DEV
+		int i;
+
 		jack->input_dev = input_allocate_device();
 		if (jack->input_dev == NULL) {
 			err = -ENOMEM;
@@ -245,6 +255,7 @@  int snd_jack_new(struct snd_card *card, const char *id, int type,
 				input_set_capability(jack->input_dev, EV_SW,
 						     jack_switch_types[i]);
 
+#endif /* CONFIG_SND_JACK_INPUT_DEV */
 	}
 
 	err = snd_device_new(card, SNDRV_DEV_JACK, jack, &ops);
@@ -262,13 +273,16 @@  int snd_jack_new(struct snd_card *card, const char *id, int type,
 	return 0;
 
 fail_input:
+#ifdef CONFIG_SND_JACK_INPUT_DEV
 	input_free_device(jack->input_dev);
+#endif
 	kfree(jack->id);
 	kfree(jack);
 	return err;
 }
 EXPORT_SYMBOL(snd_jack_new);
 
+#ifdef CONFIG_SND_JACK_INPUT_DEV
 /**
  * snd_jack_set_parent - Set the parent device for a jack
  *
@@ -326,10 +340,10 @@  int snd_jack_set_key(struct snd_jack *jack, enum snd_jack_types type,
 
 	jack->type |= type;
 	jack->key[key] = keytype;
-
 	return 0;
 }
 EXPORT_SYMBOL(snd_jack_set_key);
+#endif /* CONFIG_SND_JACK_INPUT_DEV */
 
 /**
  * snd_jack_report - Report the current status of a jack
@@ -340,7 +354,9 @@  EXPORT_SYMBOL(snd_jack_set_key);
 void snd_jack_report(struct snd_jack *jack, int status)
 {
 	struct snd_jack_kctl *jack_kctl;
+#ifdef CONFIG_SND_JACK_INPUT_DEV
 	int i;
+#endif
 
 	if (!jack)
 		return;
@@ -349,6 +365,7 @@  void snd_jack_report(struct snd_jack *jack, int status)
 		snd_kctl_jack_report(jack->card, jack_kctl->kctl,
 					    status & jack_kctl->mask_bits);
 
+#ifdef CONFIG_SND_JACK_INPUT_DEV
 	if (!jack->input_dev)
 		return;
 
@@ -369,6 +386,6 @@  void snd_jack_report(struct snd_jack *jack, int status)
 	}
 
 	input_sync(jack->input_dev);
-
+#endif /* CONFIG_SND_JACK_INPUT_DEV */
 }
 EXPORT_SYMBOL(snd_jack_report);
diff --git a/sound/pci/Kconfig b/sound/pci/Kconfig
index 8f6594a7d37f..32151d8c6bb8 100644
--- a/sound/pci/Kconfig
+++ b/sound/pci/Kconfig
@@ -866,7 +866,7 @@  config SND_VIRTUOSO
 	select SND_OXYGEN_LIB
 	select SND_PCM
 	select SND_MPU401_UART
-	select SND_JACK if INPUT=y || INPUT=SND
+	select SND_JACK
 	help
 	  Say Y here to include support for sound cards based on the
 	  Asus AV66/AV100/AV200 chips, i.e., Xonar D1, DX, D2, D2X, DS, DSX,
diff --git a/sound/pci/hda/Kconfig b/sound/pci/hda/Kconfig
index e94cfd5c69f7..bb02c2d48fd5 100644
--- a/sound/pci/hda/Kconfig
+++ b/sound/pci/hda/Kconfig
@@ -4,7 +4,7 @@  config SND_HDA
 	tristate
 	select SND_PCM
 	select SND_VMASTER
-	select SND_JACK if INPUT=y || INPUT=SND
+	select SND_JACK
 	select SND_HDA_CORE
 
 config SND_HDA_INTEL
diff --git a/sound/soc/Kconfig b/sound/soc/Kconfig
index 7ea66ee3653f..182d92efc7c8 100644
--- a/sound/soc/Kconfig
+++ b/sound/soc/Kconfig
@@ -6,7 +6,7 @@  menuconfig SND_SOC
 	tristate "ALSA for SoC audio support"
 	select SND_PCM
 	select AC97_BUS if SND_SOC_AC97_BUS
-	select SND_JACK if INPUT=y || INPUT=SND
+	select SND_JACK
 	select REGMAP_I2C if I2C
 	select REGMAP_SPI if SPI_MASTER
 	---help---