text: // SPDX-License-Identifier: GPL-2.0-or-later
  /*
   *  Jack abstraction layer
   *
   *  Copyright 2008 Wolfson Microelectronics
   */
  
  #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>
  
  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 */
  #ifdef CONFIG_SND_JACK_INJECTION_DEBUG
  	struct dentry *jack_debugfs_root; /* jack_kctl debugfs root */
  #endif
  };
  
  #ifdef CONFIG_SND_JACK_INPUT_DEV
  static const 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;
  
  	down_write(&card->controls_rwsem);
  	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);
  	}
  	up_write(&card->controls_rwsem);
  
  	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 */
  
  #ifdef CONFIG_SND_JACK_INJECTION_DEBUG
  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;
  	int len, ret;
  	char buf[128];
  
  	len = scnprintf(buf, sizeof(buf), "%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);
  
  	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;
  	int ret, err;
  	unsigned long enable;
  	char buf[8] = { 0 };
  
  	ret = simple_write_to_buffer(buf, sizeof(buf) - 1, ppos, from, count);
  	err = kstrtoul(buf, 0, &enable);
  	if (err)
  		return err;
  
  	if (jack_kctl->sw_inject_enable == (!!enable))
  		return ret;
  
  	jack_kctl->sw_inject_enable = !!enable;
  
  	if (!jack_kctl->sw_inject_enable)
  		snd_jack_report(jack_kctl->jack, jack_kctl->jack->hw_status_cache);
  
  	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;
  	int ret, err;
  	unsigned long enable;
  	char buf[8] = { 0 };
  
  	if (!jack_kctl->sw_inject_enable)
  		return -EINVAL;
  
  	ret = simple_write_to_buffer(buf, sizeof(buf) - 1, ppos, from, count);
  	err = kstrtoul(buf, 0, &enable);
  	if (err)
  		return err;
  
  	snd_jack_inject_report(jack_kctl, !!enable ? jack_kctl->mask_bits : 0);
  
  	return ret;
  }
  
  static ssize_t jack_kctl_id_read(struct file *file,
  				 char __user *to, size_t count, loff_t *ppos)
  {
  	struct snd_jack_kctl *jack_kctl = file->private_data;
  	char buf[64];
  	int len, ret;
  
  	len = scnprintf(buf, sizeof(buf), "%s\n", jack_kctl->kctl->id.name);
  	ret = simple_read_from_buffer(to, count, ppos, buf, len);
  
  	return ret;
  }
  
  /* the bit definition is aligned with snd_jack_types in jack.h */
  static const char * const jack_events_name[] = {
  	"HEADPHONE(0x0001)", "MICROPHONE(0x0002)", "LINEOUT(0x0004)",
  	"MECHANICAL(0x0008)", "VIDEOOUT(0x0010)", "LINEIN(0x0020)",
  	"", "", "", "BTN_5(0x0200)", "BTN_4(0x0400)", "BTN_3(0x0800)",
  	"BTN_2(0x1000)", "BTN_1(0x2000)", "BTN_0(0x4000)", "",
  };
  
  /* the recommended buffer size is 256 */
  static int parse_mask_bits(unsigned int mask_bits, char *buf, size_t buf_size)
  {
  	int i;
  
  	scnprintf(buf, buf_size, "0x%04x", mask_bits);
  
  	for (i = 0; i < ARRAY_SIZE(jack_events_name); i++)
  		if (mask_bits & (1 << i)) {
  			strlcat(buf, " ", buf_size);
  			strlcat(buf, jack_events_name[i], buf_size);
  		}
  	strlcat(buf, "\n", buf_size);
  
  	return strlen(buf);
  }
  
  static ssize_t jack_kctl_mask_bits_read(struct file *file,
  					char __user *to, size_t count, loff_t *ppos)
  {
  	struct snd_jack_kctl *jack_kctl = file->private_data;
  	char buf[256];
  	int len, ret;
  
  	len = parse_mask_bits(jack_kctl->mask_bits, buf, sizeof(buf));
  	ret = simple_read_from_buffer(to, count, ppos, buf, len);
  
  	return ret;
  }
  
  static ssize_t jack_kctl_status_read(struct file *file,
  				     char __user *to, size_t count, loff_t *ppos)
  {
  	struct snd_jack_kctl *jack_kctl = file->private_data;
  	char buf[16];
  	int len, ret;
  
  	len = scnprintf(buf, sizeof(buf), "%s\n", jack_kctl->kctl->private_value ?
  			"Plugged" : "Unplugged");
  	ret = simple_read_from_buffer(to, count, ppos, buf, len);
  
  	return ret;
  }
  
  #ifdef CONFIG_SND_JACK_INPUT_DEV
  static ssize_t jack_type_read(struct file *file,
  			      char __user *to, size_t count, loff_t *ppos)
  {
  	struct snd_jack_kctl *jack_kctl = file->private_data;
  	char buf[256];
  	int len, ret;
  
  	len = parse_mask_bits(jack_kctl->jack->type, buf, sizeof(buf));
  	ret = simple_read_from_buffer(to, count, ppos, buf, len);
  
  	return ret;
  }
  
  static const struct file_operations jack_type_fops = {
  	.open = simple_open,
  	.read = jack_type_read,
  	.llseek = default_llseek,
  };
  #endif
  
  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 const struct file_operations jack_kctl_id_fops = {
  	.open = simple_open,
  	.read = jack_kctl_id_read,
  	.llseek = default_llseek,
  };
  
  static const struct file_operations jack_kctl_mask_bits_fops = {
  	.open = simple_open,
  	.read = jack_kctl_mask_bits_read,
  	.llseek = default_llseek,
  };
  
  static const struct file_operations jack_kctl_status_fops = {
  	.open = simple_open,
  	.read = jack_kctl_status_read,
  	.llseek = default_llseek,
  };
  
  static int snd_jack_debugfs_add_inject_node(struct snd_jack *jack,
  					    struct snd_jack_kctl *jack_kctl)
  {
  	char *tname;
  	int i;
  
  	/* Don't create injection interface for Phantom jacks */
  	if (strstr(jack_kctl->kctl->id.name, "Phantom"))
  		return 0;
  
  	tname = kstrdup(jack_kctl->kctl->id.name, GFP_KERNEL);
  	if (!tname)
  		return -ENOMEM;
  
  	/* replace the chars which are not suitable for folder's name with _ */
  	for (i = 0; tname[i]; i++)
  		if (!isalnum(tname[i]))
  			tname[i] = '_';
  
  	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);
  
  	debugfs_create_file("kctl_id", 0444, jack_kctl->jack_debugfs_root, jack_kctl,
  			    &jack_kctl_id_fops);
  
  	debugfs_create_file("mask_bits", 0444, jack_kctl->jack_debugfs_root, jack_kctl,
  			    &jack_kctl_mask_bits_fops);
  
  	debugfs_create_file("status", 0444, jack_kctl->jack_debugfs_root, jack_kctl,
  			    &jack_kctl_status_fops);
  
  #ifdef CONFIG_SND_JACK_INPUT_DEV
  	debugfs_create_file("type", 0444, jack_kctl->jack_debugfs_root, jack_kctl,
  			    &jack_type_fops);
  #endif
  	return 0;
  }
  
  static void snd_jack_debugfs_clear_inject_node(struct snd_jack_kctl *jack_kctl)
  {
  	debugfs_remove(jack_kctl->jack_debugfs_root);
  	jack_kctl->jack_debugfs_root = NULL;
  }
  #else /* CONFIG_SND_JACK_INJECTION_DEBUG */
  static int snd_jack_debugfs_add_inject_node(struct snd_jack *jack,
  					    struct snd_jack_kctl *jack_kctl)
  {
  	return 0;
  }
  
  static void snd_jack_debugfs_clear_inject_node(struct snd_jack_kctl *jack_kctl)
  {
  }
  #endif /* CONFIG_SND_JACK_INJECTION_DEBUG */
  
  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) {
  		snd_jack_debugfs_clear_inject_node(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)
  {
  	jack_kctl->jack = jack;
  	list_add_tail(&jack_kctl->list, &jack->kctl_list);
  	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)
  {
  	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 const 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);
  	if (jack->id == NULL) {
  		kfree(jack);
  		return -ENOMEM;
  	}
  
  	/* 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;
  	unsigned int mask_bits = 0;
  #ifdef CONFIG_SND_JACK_INPUT_DEV
  	int i;
  #endif
  
  	if (!jack)
  		return;
  
  	jack->hw_status_cache = status;
  
  	list_for_each_entry(jack_kctl, &jack->kctl_list, list)
  		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) & ~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) & ~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 */
  }
  EXPORT_SYMBOL(snd_jack_report);
  