[RFC][PATCH v2 1/1] alsa: jack: implement software jack injection via debugfs
Hui Wang
hui.wang at canonical.com
Wed Dec 16 12:46:28 CET 2020
We want to perform remote audio auto test, need the audio jack to
change from plugout to plugin or vice versa by software ways.
Here the design is creating a sound-core root folder in the debugfs
dir, and each sound card will create a folder cardN under sound-core,
then the sound jack will create folders by jack_ctrl->ctrl->id.name,
and will create 2 file nodes jackin_inject and sw_inject_enable in
the folder, this is the layout of folder on a machine with 2 sound
cards:
$tree $debugfs_mount_dir/sound-core
sound-core/
├── card0
│ ├── HDMI!DP,pcm=10 Jack
│ │ ├── jackin_inject
│ │ └── sw_inject_enable
│ ├── HDMI!DP,pcm=11 Jack
│ │ ├── jackin_inject
│ │ └── sw_inject_enable
│ ├── HDMI!DP,pcm=3 Jack
│ │ ├── jackin_inject
│ │ └── sw_inject_enable
│ ├── HDMI!DP,pcm=7 Jack
│ │ ├── jackin_inject
│ │ └── sw_inject_enable
│ ├── HDMI!DP,pcm=8 Jack
│ │ ├── jackin_inject
│ │ └── sw_inject_enable
│ └── HDMI!DP,pcm=9 Jack
│ ├── jackin_inject
│ └── sw_inject_enable
└── card1
├── HDMI!DP,pcm=3 Jack
│ ├── jackin_inject
│ └── sw_inject_enable
├── HDMI!DP,pcm=4 Jack
│ ├── jackin_inject
│ └── sw_inject_enable
├── HDMI!DP,pcm=5 Jack
│ ├── jackin_inject
│ └── sw_inject_enable
├── Headphone Jack
│ ├── jackin_inject
│ └── sw_inject_enable
├── Headset Jack
│ ├── jackin_inject
│ └── sw_inject_enable
└── Mic Jack
├── jackin_inject
└── sw_inject_enable
Suppose users want to enable jack injection for Headphone, they need
to run $sudo sh -c 'echo 1 > 'Headphone Jack'/sw_inject_enable', then
users could change the Headphone Jack state through jackin_inject and
this Jack's state will not be changed by non-injection ways anymore
until users echo 0 to sw_inject_enable.
Users could run $sudo sh -c 'echo 1 > 'Headphone Jack'/jackin_inject'
to trigger the Headphone jack to plugin or echo 0 to trigger it to
plugout.
If users finish their test, they could run
$sudo sh -c 'echo 0 > 'Headphone Jack'/sw_inject_enable' to disable
injection and let non-injection ways control this Jack.
Signed-off-by: Hui Wang <hui.wang at canonical.com>
---
include/sound/core.h | 2 +
sound/core/init.c | 7 ++
sound/core/jack.c | 202 ++++++++++++++++++++++++++++++++++++-------
sound/core/sound.c | 8 ++
4 files changed, 188 insertions(+), 31 deletions(-)
diff --git a/include/sound/core.h b/include/sound/core.h
index 0462c577d7a3..11d61e4248ee 100644
--- a/include/sound/core.h
+++ b/include/sound/core.h
@@ -122,6 +122,7 @@ struct snd_card {
size_t total_pcm_alloc_bytes; /* total amount of allocated buffers */
struct mutex memory_mutex; /* protection for the above */
+ struct dentry *debugfs_root; /* debugfs root for card */
#ifdef CONFIG_PM
unsigned int power_state; /* power state */
@@ -180,6 +181,7 @@ static inline struct device *snd_card_get_device_link(struct snd_card *card)
extern int snd_major;
extern int snd_ecards_limit;
extern struct class *sound_class;
+extern struct dentry *sound_core_debugfs_root;
void snd_request_card(int card);
diff --git a/sound/core/init.c b/sound/core/init.c
index 764dbe673d48..a9ceaf788019 100644
--- a/sound/core/init.c
+++ b/sound/core/init.c
@@ -13,6 +13,7 @@
#include <linux/time.h>
#include <linux/ctype.h>
#include <linux/pm.h>
+#include <linux/debugfs.h>
#include <linux/completion.h>
#include <sound/core.h>
@@ -163,6 +164,7 @@ int snd_card_new(struct device *parent, int idx, const char *xid,
{
struct snd_card *card;
int err;
+ char name[8];
if (snd_BUG_ON(!card_ret))
return -EINVAL;
@@ -246,6 +248,10 @@ int snd_card_new(struct device *parent, int idx, const char *xid,
dev_err(parent, "unable to create card info\n");
goto __error_ctl;
}
+
+ sprintf(name, "card%d", idx);
+ card->debugfs_root = debugfs_create_dir(name, sound_core_debugfs_root);
+
*card_ret = card;
return 0;
@@ -418,6 +424,7 @@ int snd_card_disconnect(struct snd_card *card)
/* notify all devices that we are disconnected */
snd_device_disconnect_all(card);
+ debugfs_remove(card->debugfs_root);
snd_info_card_disconnect(card);
if (card->registered) {
device_del(&card->card_dev);
diff --git a/sound/core/jack.c b/sound/core/jack.c
index 503c8af79d55..fa6b3cdc0431 100644
--- a/sound/core/jack.c
+++ b/sound/core/jack.c
@@ -8,6 +8,8 @@
#include <linux/input.h>
#include <linux/slab.h>
#include <linux/module.h>
+#include <linux/ctype.h>
+#include <linux/debugfs.h>
#include <sound/jack.h>
#include <sound/core.h>
#include <sound/control.h>
@@ -16,6 +18,9 @@ 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 */
+ struct snd_jack *jack; /* pointer to struct snd_jack */
+ bool sw_inject_enable; /* allow to inject plug event via debugfs */
+ struct dentry *jack_debugfs_root; /* jack_kctl debugfs root */
};
#ifdef CONFIG_SND_JACK_INPUT_DEV
@@ -109,12 +114,174 @@ static int snd_jack_dev_register(struct snd_device *device)
}
#endif /* CONFIG_SND_JACK_INPUT_DEV */
+static void _snd_jack_report(struct snd_jack *jack, int status, bool from_inject)
+{
+ struct snd_jack_kctl *jack_kctl;
+ unsigned int mask_bits = 0;
+#ifdef CONFIG_SND_JACK_INPUT_DEV
+ int i;
+#endif
+ list_for_each_entry(jack_kctl, &jack->kctl_list, list) {
+ if (jack_kctl->sw_inject_enable == from_inject)
+ snd_kctl_jack_report(jack->card, jack_kctl->kctl,
+ status & jack_kctl->mask_bits);
+ else if (jack_kctl->sw_inject_enable)
+ mask_bits |= 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 (!from_inject)
+ testbit &= ~mask_bits;
+ 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 (!from_inject)
+ testbit &= ~mask_bits;
+ 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 */
+}
+
+#ifdef CONFIG_DEBUG_FS
+static ssize_t sw_inject_enable_read(struct file *file,
+ char __user *to, size_t count, loff_t *ppos)
+{
+ struct snd_jack_kctl *jack_kctl = file->private_data;
+ char *buf;
+ int len, ret;
+
+ buf = kzalloc(PAGE_SIZE, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ len = scnprintf(buf, PAGE_SIZE, "%s: %s\t\t%s: %i\n", "Jack", jack_kctl->kctl->id.name,
+ "Inject Enabled", jack_kctl->sw_inject_enable);
+ ret = simple_read_from_buffer(to, count, ppos, buf, len);
+
+ kfree(buf);
+ return ret;
+}
+
+static ssize_t sw_inject_enable_write(struct file *file,
+ const char __user *from, size_t count, loff_t *ppos)
+{
+ struct snd_jack_kctl *jack_kctl = file->private_data;
+ char *buf;
+ int ret, err;
+ unsigned long enable;
+
+ buf = kzalloc(count, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ ret = simple_write_to_buffer(buf, count, ppos, from, count);
+ err = kstrtoul(buf, 0, &enable);
+ if (err) {
+ ret = err;
+ goto exit;
+ }
+
+ jack_kctl->sw_inject_enable = !!enable;
+
+ exit:
+ kfree(buf);
+ return ret;
+}
+
+static ssize_t jackin_inject_write(struct file *file,
+ const char __user *from, size_t count, loff_t *ppos)
+{
+ struct snd_jack_kctl *jack_kctl = file->private_data;
+ char *buf;
+ int ret, err;
+ unsigned long enable;
+
+ if (!jack_kctl->sw_inject_enable)
+ return -EINVAL;
+
+ buf = kzalloc(count, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ ret = simple_write_to_buffer(buf, count, ppos, from, count);
+ err = kstrtoul(buf, 0, &enable);
+ if (err) {
+ ret = err;
+ goto exit;
+ }
+
+ _snd_jack_report(jack_kctl->jack, !!enable ? jack_kctl->mask_bits : 0, true);
+
+ exit:
+ kfree(buf);
+ return ret;
+}
+
+static const struct file_operations sw_inject_enable_fops = {
+ .open = simple_open,
+ .read = sw_inject_enable_read,
+ .write = sw_inject_enable_write,
+ .llseek = default_llseek,
+};
+
+static const struct file_operations jackin_inject_fops = {
+ .open = simple_open,
+ .write = jackin_inject_write,
+ .llseek = default_llseek,
+};
+
+static int snd_jack_debugfs_add_inject_node(struct snd_jack *jack,
+ struct snd_jack_kctl *jack_kctl)
+{
+ char *tname;
+
+ /* the folder's name can't contains '/', need to replace it with '!' as lib/kobject.c does */
+ tname = kstrdup(jack_kctl->kctl->id.name, GFP_KERNEL);
+ if (!tname)
+ return -ENOMEM;
+ strreplace(tname, '/', '!');
+ jack_kctl->jack_debugfs_root = debugfs_create_dir(tname, jack->card->debugfs_root);
+ kfree(tname);
+
+ debugfs_create_file("sw_inject_enable", 0644, jack_kctl->jack_debugfs_root, jack_kctl,
+ &sw_inject_enable_fops);
+
+ debugfs_create_file("jackin_inject", 0200, jack_kctl->jack_debugfs_root, jack_kctl,
+ &jackin_inject_fops);
+
+ return 0;
+}
+#else
+static int snd_jack_debugfs_add_inject_node(struct snd_jack *jack,
+ struct snd_jack_kctl *jack_kctl)
+{
+ return 0;
+}
+#endif
+
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) {
+ debugfs_remove(jack_kctl->jack_debugfs_root);
list_del(&jack_kctl->list);
kfree(jack_kctl);
}
@@ -122,7 +289,10 @@ static void snd_jack_kctl_private_free(struct snd_kcontrol *kctl)
static void snd_jack_kctl_add(struct snd_jack *jack, struct snd_jack_kctl *jack_kctl)
{
+ jack_kctl->jack = jack;
list_add_tail(&jack_kctl->list, &jack->kctl_list);
+ if (!strstr(jack_kctl->kctl->id.name, "Phantom"))
+ snd_jack_debugfs_add_inject_node(jack, jack_kctl);
}
static struct snd_jack_kctl * snd_jack_kctl_new(struct snd_card *card, const char *name, unsigned int mask)
@@ -339,39 +509,9 @@ 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;
- 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 */
+ return _snd_jack_report(jack, status, false);
}
EXPORT_SYMBOL(snd_jack_report);
diff --git a/sound/core/sound.c b/sound/core/sound.c
index b75f78f2c4b8..3039e317df93 100644
--- a/sound/core/sound.c
+++ b/sound/core/sound.c
@@ -9,6 +9,7 @@
#include <linux/time.h>
#include <linux/device.h>
#include <linux/module.h>
+#include <linux/debugfs.h>
#include <sound/core.h>
#include <sound/minors.h>
#include <sound/info.h>
@@ -39,6 +40,9 @@ MODULE_ALIAS_CHARDEV_MAJOR(CONFIG_SND_MAJOR);
int snd_ecards_limit;
EXPORT_SYMBOL(snd_ecards_limit);
+struct dentry *sound_core_debugfs_root;
+EXPORT_SYMBOL_GPL(sound_core_debugfs_root);
+
static struct snd_minor *snd_minors[SNDRV_OS_MINORS];
static DEFINE_MUTEX(sound_mutex);
@@ -395,6 +399,9 @@ static int __init alsa_sound_init(void)
unregister_chrdev(major, "alsa");
return -ENOMEM;
}
+
+ sound_core_debugfs_root = debugfs_create_dir("sound-core", NULL);
+
#ifndef MODULE
pr_info("Advanced Linux Sound Architecture Driver Initialized.\n");
#endif
@@ -403,6 +410,7 @@ static int __init alsa_sound_init(void)
static void __exit alsa_sound_exit(void)
{
+ debugfs_remove(sound_core_debugfs_root);
snd_info_done();
unregister_chrdev(major, "alsa");
}
--
2.25.1
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