diff mbox series

[RFC,v4,1/4] alsa: jack: implement software jack injection via debugfs

Message ID 20210111130557.90208-2-hui.wang@canonical.com (mailing list archive)
State New, archived
Headers show
Series design a way to change audio Jack state by software | expand

Commit Message

Hui Wang Jan. 11, 2021, 1:05 p.m. UTC
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 root folder in the debugfs
dir, and each sound card will create a folder cardN under sound,
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
sound/
├── 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.

For the jack event report, the hw jack event will call
snd_jack_report(), it will avoid to report the events if a jack_kctl's
sw_inject is enabled, also the related input_dev's events will not be
reproted.

If users inject a event, it will call snd_jack_inject_report(), it
only reports the events for this jack_kctl and reports the related
input_dev's events.

Signed-off-by: Hui Wang <hui.wang@canonical.com>
---
 include/sound/core.h |   2 +
 sound/core/init.c    |   7 ++
 sound/core/jack.c    | 182 ++++++++++++++++++++++++++++++++++++++++++-
 sound/core/sound.c   |   8 ++
 4 files changed, 195 insertions(+), 4 deletions(-)

Comments

Takashi Iwai Jan. 20, 2021, 2:51 p.m. UTC | #1
On Mon, 11 Jan 2021 14:05:54 +0100,
Hui Wang wrote:
> +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 = kvzalloc(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);

For this size of a string buffer, you don't need to allocate via
kvmalloc().  It can be on stack.


> +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 = kvzalloc(count, GFP_KERNEL);
> +	if (!buf)
> +		return -ENOMEM;
> +
> +	ret = simple_write_to_buffer(buf, count, ppos, from, count);
> +	err = kstrtoul(buf, 0, &enable);

Ditto, it's just a single number and cannot be that big.
(Also jackin_inject_write(), too.)


thanks,

Takashi
diff mbox series

Patch

diff --git a/include/sound/core.h b/include/sound/core.h
index 0462c577d7a3..15175fd44971 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_debugfs_root;
 
 void snd_request_card(int card);
 
diff --git a/sound/core/init.c b/sound/core/init.c
index 75aec71c48a8..d5ed2580f30c 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>
@@ -161,6 +162,7 @@  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;
@@ -244,6 +246,10 @@  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_debugfs_root);
+
 	*card_ret = card;
 	return 0;
 
@@ -416,6 +422,7 @@  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..0092cb6b5b79 100644
--- a/sound/core/jack.c
+++ b/sound/core/jack.c
@@ -8,6 +8,9 @@ 
 #include <linux/input.h>
 #include <linux/slab.h>
 #include <linux/module.h>
+#include <linux/ctype.h>
+#include <linux/mm.h>
+#include <linux/debugfs.h>
 #include <sound/jack.h>
 #include <sound/core.h>
 #include <sound/control.h>
@@ -16,6 +19,9 @@  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 +115,172 @@  static int snd_jack_dev_register(struct snd_device *device)
 }
 #endif /* CONFIG_SND_JACK_INPUT_DEV */
 
+#ifdef CONFIG_DEBUG_FS
+static void snd_jack_inject_report(struct snd_jack_kctl *jack_kctl, int status)
+{
+	struct snd_jack *jack;
+#ifdef CONFIG_SND_JACK_INPUT_DEV
+	int i;
+#endif
+	if (!jack_kctl)
+		return;
+
+	jack = jack_kctl->jack;
+
+	if (jack_kctl->sw_inject_enable)
+		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) & jack_kctl->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) & jack_kctl->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 */
+}
+
+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 = kvzalloc(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);
+
+	kvfree(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 = kvzalloc(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:
+	kvfree(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 = kvzalloc(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_inject_report(jack_kctl, !!enable ? jack_kctl->mask_bits : 0);
+
+ exit:
+	kvfree(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 /* CONFIG_DEBUG_FS */
+static int snd_jack_debugfs_add_inject_node(struct snd_jack *jack,
+					    struct snd_jack_kctl *jack_kctl)
+{
+	return 0;
+}
+#endif /* CONFIG_DEBUG_FS */
+
 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 +288,10 @@  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)
@@ -340,6 +509,7 @@  EXPORT_SYMBOL(snd_jack_set_key);
 void snd_jack_report(struct snd_jack *jack, int status)
 {
 	struct snd_jack_kctl *jack_kctl;
+	unsigned int mask_bits = 0;
 #ifdef CONFIG_SND_JACK_INPUT_DEV
 	int i;
 #endif
@@ -348,15 +518,18 @@  void snd_jack_report(struct snd_jack *jack, int status)
 		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);
+		if (jack_kctl->sw_inject_enable)
+			mask_bits |= jack_kctl->mask_bits;
+		else
+			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;
+		int testbit = ((SND_JACK_BTN_0 >> i) & ~mask_bits);
 
 		if (jack->type & testbit)
 			input_report_key(jack->input_dev, jack->key[i],
@@ -364,7 +537,8 @@  void snd_jack_report(struct snd_jack *jack, int status)
 	}
 
 	for (i = 0; i < ARRAY_SIZE(jack_switch_types); i++) {
-		int testbit = 1 << i;
+		int testbit = ((1 << i) & ~mask_bits);
+
 		if (jack->type & testbit)
 			input_report_switch(jack->input_dev,
 					    jack_switch_types[i],
diff --git a/sound/core/sound.c b/sound/core/sound.c
index b75f78f2c4b8..8a80f0440455 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_debugfs_root;
+EXPORT_SYMBOL_GPL(sound_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_debugfs_root = debugfs_create_dir("sound", 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_debugfs_root);
 	snd_info_done();
 	unregister_chrdev(major, "alsa");
 }