linux/sound/core/jack.c
Takashi Iwai fe0d128c57 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.

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>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2016-02-23 09:03:07 +01:00

392 lines
9.9 KiB
C

/*
* Jack abstraction layer
*
* Copyright 2008 Wolfson Microelectronics
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#include <linux/input.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <sound/jack.h>
#include <sound/core.h>
#include <sound/control.h>
struct snd_jack_kctl {
struct snd_kcontrol *kctl;
struct list_head list; /* list of controls belong to the same jack */
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,
SW_LINEOUT_INSERT,
SW_JACK_PHYSICAL_INSERT,
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)
return 0;
/* If the input device is registered with the input subsystem
* then we need to use a different deallocator. */
if (jack->registered)
input_unregister_device(jack->input_dev);
else
input_free_device(jack->input_dev);
jack->input_dev = NULL;
#endif /* CONFIG_SND_JACK_INPUT_DEV */
return 0;
}
static int snd_jack_dev_free(struct snd_device *device)
{
struct snd_jack *jack = device->device_data;
struct snd_card *card = device->card;
struct snd_jack_kctl *jack_kctl, *tmp_jack_kctl;
list_for_each_entry_safe(jack_kctl, tmp_jack_kctl, &jack->kctl_list, list) {
list_del_init(&jack_kctl->list);
snd_ctl_remove(card, jack_kctl->kctl);
}
if (jack->private_free)
jack->private_free(jack);
snd_jack_dev_disconnect(device);
kfree(jack->id);
kfree(jack);
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;
struct snd_card *card = device->card;
int err, i;
snprintf(jack->name, sizeof(jack->name), "%s %s",
card->shortname, jack->id);
if (!jack->input_dev)
return 0;
jack->input_dev->name = jack->name;
/* Default to the sound card device. */
if (!jack->input_dev->dev.parent)
jack->input_dev->dev.parent = snd_card_get_device_link(card);
/* Add capabilities for any keys that are enabled */
for (i = 0; i < ARRAY_SIZE(jack->key); i++) {
int testbit = SND_JACK_BTN_0 >> i;
if (!(jack->type & testbit))
continue;
if (!jack->key[i])
jack->key[i] = BTN_0 + i;
input_set_capability(jack->input_dev, EV_KEY, jack->key[i]);
}
err = input_register_device(jack->input_dev);
if (err == 0)
jack->registered = 1;
return err;
}
#endif /* CONFIG_SND_JACK_INPUT_DEV */
static void snd_jack_kctl_private_free(struct snd_kcontrol *kctl)
{
struct snd_jack_kctl *jack_kctl;
jack_kctl = kctl->private_data;
if (jack_kctl) {
list_del(&jack_kctl->list);
kfree(jack_kctl);
}
}
static void snd_jack_kctl_add(struct snd_jack *jack, struct snd_jack_kctl *jack_kctl)
{
list_add_tail(&jack_kctl->list, &jack->kctl_list);
}
static struct snd_jack_kctl * snd_jack_kctl_new(struct snd_card *card, const char *name, unsigned int mask)
{
struct snd_kcontrol *kctl;
struct snd_jack_kctl *jack_kctl;
int err;
kctl = snd_kctl_jack_new(name, card);
if (!kctl)
return NULL;
err = snd_ctl_add(card, kctl);
if (err < 0)
return NULL;
jack_kctl = kzalloc(sizeof(*jack_kctl), GFP_KERNEL);
if (!jack_kctl)
goto error;
jack_kctl->kctl = kctl;
jack_kctl->mask_bits = mask;
kctl->private_data = jack_kctl;
kctl->private_free = snd_jack_kctl_private_free;
return jack_kctl;
error:
snd_ctl_free_one(kctl);
return NULL;
}
/**
* snd_jack_add_new_kctl - Create a new snd_jack_kctl and add it to jack
* @jack: the jack instance which the kctl will attaching to
* @name: the name for the snd_kcontrol object
* @mask: a bitmask of enum snd_jack_type values that can be detected
* by this snd_jack_kctl object.
*
* Creates a new snd_kcontrol object and adds it to the jack kctl_list.
*
* Return: Zero if successful, or a negative error code on failure.
*/
int snd_jack_add_new_kctl(struct snd_jack *jack, const char * name, int mask)
{
struct snd_jack_kctl *jack_kctl;
jack_kctl = snd_jack_kctl_new(jack->card, name, mask);
if (!jack_kctl)
return -ENOMEM;
snd_jack_kctl_add(jack, jack_kctl);
return 0;
}
EXPORT_SYMBOL(snd_jack_add_new_kctl);
/**
* snd_jack_new - Create a new jack
* @card: the card instance
* @id: an identifying string for this jack
* @type: a bitmask of enum snd_jack_type values that can be detected by
* this jack
* @jjack: Used to provide the allocated jack object to the caller.
* @initial_kctl: if true, create a kcontrol and add it to the jack list.
* @phantom_jack: Don't create a input device for phantom jacks.
*
* Creates a new jack object.
*
* Return: Zero if successful, or a negative error code on failure.
* On success @jjack will be initialised.
*/
int snd_jack_new(struct snd_card *card, const char *id, int type,
struct snd_jack **jjack, bool initial_kctl, bool phantom_jack)
{
struct snd_jack *jack;
struct snd_jack_kctl *jack_kctl = NULL;
int err;
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) {
jack_kctl = snd_jack_kctl_new(card, id, type);
if (!jack_kctl)
return -ENOMEM;
}
jack = kzalloc(sizeof(struct snd_jack), GFP_KERNEL);
if (jack == NULL)
return -ENOMEM;
jack->id = kstrdup(id, GFP_KERNEL);
/* 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;
goto fail_input;
}
jack->input_dev->phys = "ALSA";
jack->type = type;
for (i = 0; i < SND_JACK_SWITCH_TYPES; i++)
if (type & (1 << i))
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);
if (err < 0)
goto fail_input;
jack->card = card;
INIT_LIST_HEAD(&jack->kctl_list);
if (initial_kctl)
snd_jack_kctl_add(jack, jack_kctl);
*jjack = jack;
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
*
* @jack: The jack to configure
* @parent: The device to set as parent for the jack.
*
* Set the parent for the jack devices in the device tree. This
* function is only valid prior to registration of the jack. If no
* parent is configured then the parent device will be the sound card.
*/
void snd_jack_set_parent(struct snd_jack *jack, struct device *parent)
{
WARN_ON(jack->registered);
if (!jack->input_dev)
return;
jack->input_dev->dev.parent = parent;
}
EXPORT_SYMBOL(snd_jack_set_parent);
/**
* snd_jack_set_key - Set a key mapping on a jack
*
* @jack: The jack to configure
* @type: Jack report type for this key
* @keytype: Input layer key type to be reported
*
* Map a SND_JACK_BTN_ button type to an input layer key, allowing
* reporting of keys on accessories via the jack abstraction. If no
* mapping is provided but keys are enabled in the jack type then
* BTN_n numeric buttons will be reported.
*
* If jacks are not reporting via the input API this call will have no
* effect.
*
* Note that this is intended to be use by simple devices with small
* numbers of keys that can be reported. It is also possible to
* access the input device directly - devices with complex input
* capabilities on accessories should consider doing this rather than
* using this abstraction.
*
* This function may only be called prior to registration of the jack.
*
* Return: Zero if successful, or a negative error code on failure.
*/
int snd_jack_set_key(struct snd_jack *jack, enum snd_jack_types type,
int keytype)
{
int key = fls(SND_JACK_BTN_0) - fls(type);
WARN_ON(jack->registered);
if (!keytype || key >= ARRAY_SIZE(jack->key))
return -EINVAL;
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
*
* @jack: The jack to report status for
* @status: The current status of the jack
*/
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;
list_for_each_entry(jack_kctl, &jack->kctl_list, list)
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;
for (i = 0; i < ARRAY_SIZE(jack->key); i++) {
int testbit = SND_JACK_BTN_0 >> i;
if (jack->type & testbit)
input_report_key(jack->input_dev, jack->key[i],
status & testbit);
}
for (i = 0; i < ARRAY_SIZE(jack_switch_types); i++) {
int testbit = 1 << i;
if (jack->type & testbit)
input_report_switch(jack->input_dev,
jack_switch_types[i],
status & testbit);
}
input_sync(jack->input_dev);
#endif /* CONFIG_SND_JACK_INPUT_DEV */
}
EXPORT_SYMBOL(snd_jack_report);