/* * drivers/extcon/extcon.c - External Connector (extcon) framework. * * External connector (extcon) class driver * * Copyright (C) 2015 Samsung Electronics * Author: Chanwoo Choi <cw00.choi@samsung.com> * * Copyright (C) 2012 Samsung Electronics * Author: Donggeun Kim <dg77.kim@samsung.com> * Author: MyungJoo Ham <myungjoo.ham@samsung.com> * * based on android/drivers/switch/switch_class.c * Copyright (C) 2008 Google, Inc. * Author: Mike Lockwood <lockwood@android.com> * * This software is licensed under the terms of the GNU General Public * License version 2, as published by the Free Software Foundation, and * may be copied, distributed, and modified under those terms. * * 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. */ #include <linux/module.h>#include <linux/types.h>#include <linux/init.h>#include <linux/device.h>#include <linux/fs.h>#include <linux/err.h>#include <linux/extcon.h>#include <linux/of.h>#include <linux/slab.h>#include <linux/sysfs.h> #define SUPPORTED_CABLE_MAX 32#define CABLE_NAME_MAX 30 static const char *extcon_name[] = { [EXTCON_NONE] = "NONE", /* USB external connector */ [EXTCON_USB] = "USB", [EXTCON_USB_HOST] = "USB-HOST", /* Charging external connector */ [EXTCON_CHG_USB_SDP] = "SDP", [EXTCON_CHG_USB_DCP] = "DCP", [EXTCON_CHG_USB_CDP] = "CDP", [EXTCON_CHG_USB_ACA] = "ACA", [EXTCON_CHG_USB_FAST] = "FAST-CHARGER", [EXTCON_CHG_USB_SLOW] = "SLOW-CHARGER", /* Jack external connector */ [EXTCON_JACK_MICROPHONE] = "MICROPHONE", [EXTCON_JACK_HEADPHONE] = "HEADPHONE", [EXTCON_JACK_LINE_IN] = "LINE-IN", [EXTCON_JACK_LINE_OUT] = "LINE-OUT", [EXTCON_JACK_VIDEO_IN] = "VIDEO-IN", [EXTCON_JACK_VIDEO_OUT] = "VIDEO-OUT", [EXTCON_JACK_SPDIF_IN] = "SPDIF-IN", [EXTCON_JACK_SPDIF_OUT] = "SPDIF-OUT", /* Display external connector */ [EXTCON_DISP_HDMI] = "HDMI", [EXTCON_DISP_MHL] = "MHL", [EXTCON_DISP_DVI] = "DVI", [EXTCON_DISP_VGA] = "VGA", /* Miscellaneous external connector */ [EXTCON_DOCK] = "DOCK", [EXTCON_JIG] = "JIG", [EXTCON_MECHANICAL] = "MECHANICAL", NULL,}; /** * struct extcon_cable - An internal data for each cable of extcon device. * @edev: The extcon device * @cable_index: Index of this cable in the edev * @attr_g: Attribute group for the cable * @attr_name: "name" sysfs entry * @attr_state: "state" sysfs entry * @attrs: Array pointing to attr_name and attr_state for attr_g */struct extcon_cable { struct extcon_dev *edev; int cable_index; struct attribute_group attr_g; struct device_attribute attr_name; struct device_attribute attr_state; struct attribute *attrs[3]; /* to be fed to attr_g.attrs */}; static struct class *extcon_class;#if defined(CONFIG_ANDROID)static struct class_compat *switch_class;#endif /* CONFIG_ANDROID */ static LIST_HEAD(extcon_dev_list);static DEFINE_MUTEX(extcon_dev_list_lock); /** * check_mutually_exclusive - Check if new_state violates mutually_exclusive * condition. * @edev: the extcon device * @new_state: new cable attach status for @edev * * Returns 0 if nothing violates. Returns the index + 1 for the first * violated condition. */static int check_mutually_exclusive(struct extcon_dev *edev, u32 new_state){ int i = 0; if (!edev->mutually_exclusive) return 0; for (i = 0; edev->mutually_exclusive[i]; i++) { int weight; u32 correspondants = new_state & edev->mutually_exclusive[i]; /* calculate the total number of bits set */ weight = hweight32(correspondants); if (weight > 1) return i + 1; } return 0;} static int find_cable_index_by_id(struct extcon_dev *edev, const unsigned int id){ int i; /* Find the the index of extcon cable in edev->supported_cable */ for (i = 0; i < edev->max_supported; i++) { if (edev->supported_cable[i] == id) return i; } return -EINVAL;} static bool is_extcon_changed(u32 prev, u32 new, int idx, bool *attached){ if (((prev >> idx) & 0x1) != ((new >> idx) & 0x1)) { *attached = ((new >> idx) & 0x1) ? true : false; return true; } return false;} static ssize_t state_show(struct device *dev, struct device_attribute *attr, char *buf){ int i, count = 0; struct extcon_dev *edev = dev_get_drvdata(dev); if (edev->max_supported == 0) return sprintf(buf, "%u\n", edev->state); for (i = 0; i < edev->max_supported; i++) { count += sprintf(buf + count, "%s=%d\n", extcon_name[edev->supported_cable[i]], !!(edev->state & (1 << i))); } return count;} static ssize_t state_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count){ u32 state; ssize_t ret = 0; struct extcon_dev *edev = dev_get_drvdata(dev); ret = sscanf(buf, "0x%x", &state); if (ret == 0) ret = -EINVAL; else ret = extcon_set_state(edev, state); if (ret < 0) return ret; return count;}static DEVICE_ATTR_RW(state); static ssize_t name_show(struct device *dev, struct device_attribute *attr, char *buf){ struct extcon_dev *edev = dev_get_drvdata(dev); return sprintf(buf, "%s\n", edev->name);}static DEVICE_ATTR_RO(name); static ssize_t cable_name_show(struct device *dev, struct device_attribute *attr, char *buf){ struct extcon_cable *cable = container_of(attr, struct extcon_cable, attr_name); int i = cable->cable_index; return sprintf(buf, "%s\n", extcon_name[cable->edev->supported_cable[i]]);} static ssize_t cable_state_show(struct device *dev, struct device_attribute *attr, char *buf){ struct extcon_cable *cable = container_of(attr, struct extcon_cable, attr_state); int i = cable->cable_index; return sprintf(buf, "%d\n", extcon_get_cable_state_(cable->edev, cable->edev->supported_cable[i]));} /** * extcon_update_state() - Update the cable attach states of the extcon device * only for the masked bits. * @edev: the extcon device * @mask: the bit mask to designate updated bits. * @state: new cable attach status for @edev * * Changing the state sends uevent with environment variable containing * the name of extcon device (envp[0]) and the state output (envp[1]). * Tizen uses this format for extcon device to get events from ports. * Android uses this format as well. * * Note that the notifier provides which bits are changed in the state * variable with the val parameter (second) to the callback. */int extcon_update_state(struct extcon_dev *edev, u32 mask, u32 state){ char name_buf[120]; char state_buf[120]; char *prop_buf; char *envp[3]; int env_offset = 0; int length; int index; unsigned long flags; bool attached; if (!edev) return -EINVAL; spin_lock_irqsave(&edev->lock, flags); if (edev->state != ((edev->state & ~mask) | (state & mask))) { u32 old_state; if (check_mutually_exclusive(edev, (edev->state & ~mask) | (state & mask))) { spin_unlock_irqrestore(&edev->lock, flags); return -EPERM; } old_state = edev->state; edev->state &= ~mask; edev->state |= state & mask; for (index = 0; index < edev->max_supported; index++) { if (is_extcon_changed(old_state, edev->state, index, &attached)) raw_notifier_call_chain(&edev->nh[index], attached, edev); } /* This could be in interrupt handler */ prop_buf = (char *)get_zeroed_page(GFP_ATOMIC); if (prop_buf) { length = name_show(&edev->dev, NULL, prop_buf); if (length > 0) { if (prop_buf[length - 1] == '\n') prop_buf[length - 1] = 0; snprintf(name_buf, sizeof(name_buf), "NAME=%s", prop_buf); envp[env_offset++] = name_buf; } length = state_show(&edev->dev, NULL, prop_buf); if (length > 0) { if (prop_buf[length - 1] == '\n') prop_buf[length - 1] = 0; snprintf(state_buf, sizeof(state_buf), "STATE=%s", prop_buf); envp[env_offset++] = state_buf; } envp[env_offset] = NULL; /* Unlock early before uevent */ spin_unlock_irqrestore(&edev->lock, flags); kobject_uevent_env(&edev->dev.kobj, KOBJ_CHANGE, envp); free_page((unsigned long)prop_buf); } else { /* Unlock early before uevent */ spin_unlock_irqrestore(&edev->lock, flags); dev_err(&edev->dev, "out of memory in extcon_set_state\n"); kobject_uevent(&edev->dev.kobj, KOBJ_CHANGE); } } else { /* No changes */ spin_unlock_irqrestore(&edev->lock, flags); } return 0;}EXPORT_SYMBOL_GPL(extcon_update_state); /** * extcon_set_state() - Set the cable attach states of the extcon device. * @edev: the extcon device * @state: new cable attach status for @edev * * Note that notifier provides which bits are changed in the state * variable with the val parameter (second) to the callback. */int extcon_set_state(struct extcon_dev *edev, u32 state){ if (!edev) return -EINVAL; return extcon_update_state(edev, 0xffffffff, state);}EXPORT_SYMBOL_GPL(extcon_set_state); /** * extcon_get_cable_state_() - Get the status of a specific cable. * @edev: the extcon device that has the cable. * @id: the unique id of each external connector in extcon enumeration. */int extcon_get_cable_state_(struct extcon_dev *edev, const unsigned int id){ int index; if (!edev) return -EINVAL; index = find_cable_index_by_id(edev, id); if (index < 0) return index; if (edev->max_supported && edev->max_supported <= index) return -EINVAL; return !!(edev->state & (1 << index));}EXPORT_SYMBOL_GPL(extcon_get_cable_state_); /** * extcon_set_cable_state_() - Set the status of a specific cable. * @edev: the extcon device that has the cable. * @id: the unique id of each external connector * in extcon enumeration. * @state: the new cable status. The default semantics is * true: attached / false: detached. */int extcon_set_cable_state_(struct extcon_dev *edev, unsigned int id, bool cable_state){ u32 state; int index; if (!edev) return -EINVAL; index = find_cable_index_by_id(edev, id); if (index < 0) return index; if (edev->max_supported && edev->max_supported <= index) return -EINVAL; state = cable_state ? (1 << index) : 0; return extcon_update_state(edev, 1 << index, state);}EXPORT_SYMBOL_GPL(extcon_set_cable_state_); /** * extcon_get_extcon_dev() - Get the extcon device instance from the name * @extcon_name: The extcon name provided with extcon_dev_register() */struct extcon_dev *extcon_get_extcon_dev(const char *extcon_name){ struct extcon_dev *sd; if (!extcon_name) return ERR_PTR(-EINVAL); mutex_lock(&extcon_dev_list_lock); list_for_each_entry(sd, &extcon_dev_list, entry) { if (!strcmp(sd->name, extcon_name)) goto out; } sd = NULL;out: mutex_unlock(&extcon_dev_list_lock); return sd;}EXPORT_SYMBOL_GPL(extcon_get_extcon_dev); /** * extcon_register_notifier() - Register a notifiee to get notified by * any attach status changes from the extcon. * @edev: the extcon device that has the external connecotr. * @id: the unique id of each external connector in extcon enumeration. * @nb: a notifier block to be registered. * * Note that the second parameter given to the callback of nb (val) is * "old_state", not the current state. The current state can be retrieved * by looking at the third pameter (edev pointer)'s state value. */int extcon_register_notifier(struct extcon_dev *edev, unsigned int id, struct notifier_block *nb){ unsigned long flags; int ret, idx; if (!nb) return -EINVAL; if (edev) { idx = find_cable_index_by_id(edev, id); if (idx < 0) return idx; spin_lock_irqsave(&edev->lock, flags); ret = raw_notifier_chain_register(&edev->nh[idx], nb); spin_unlock_irqrestore(&edev->lock, flags); } else { struct extcon_dev *extd; mutex_lock(&extcon_dev_list_lock); list_for_each_entry(extd, &extcon_dev_list, entry) { idx = find_cable_index_by_id(extd, id); if (idx >= 0) break; } mutex_unlock(&extcon_dev_list_lock); if (idx >= 0) { edev = extd; return extcon_register_notifier(extd, id, nb); } else { ret = -ENODEV; } } return ret;}EXPORT_SYMBOL_GPL(extcon_register_notifier); /** * extcon_unregister_notifier() - Unregister a notifiee from the extcon device. * @edev: the extcon device that has the external connecotr. * @id: the unique id of each external connector in extcon enumeration. * @nb: a notifier block to be registered. */int extcon_unregister_notifier(struct extcon_dev *edev, unsigned int id, struct notifier_block *nb){ unsigned long flags; int ret, idx; if (!edev || !nb) return -EINVAL; idx = find_cable_index_by_id(edev, id); if (idx < 0) return idx; spin_lock_irqsave(&edev->lock, flags); ret = raw_notifier_chain_unregister(&edev->nh[idx], nb); spin_unlock_irqrestore(&edev->lock, flags); return ret;}EXPORT_SYMBOL_GPL(extcon_unregister_notifier); static struct attribute *extcon_attrs[] = { &dev_attr_state.attr, &dev_attr_name.attr, NULL,};ATTRIBUTE_GROUPS(extcon); Lines 1–500 of 910. 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/* * drivers/extcon/extcon.c - External Connector (extcon) framework. * * External connector (extcon) class driver * * Copyright (C) 2015 Samsung Electronics * Author: Chanwoo Choi <cw00.choi@samsung.com> * * Copyright (C) 2012 Samsung Electronics * Author: Donggeun Kim <dg77.kim@samsung.com> * Author: MyungJoo Ham <myungjoo.ham@samsung.com> * * based on android/drivers/switch/switch_class.c * Copyright (C) 2008 Google, Inc. * Author: Mike Lockwood <lockwood@android.com> * * This software is licensed under the terms of the GNU General Public * License version 2, as published by the Free Software Foundation, and * may be copied, distributed, and modified under those terms. * * 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. */ #include <linux/module.h> #include <linux/types.h> #include <linux/init.h> #include <linux/device.h> #include <linux/fs.h> #include <linux/err.h> #include <linux/extcon.h> #include <linux/of.h> #include <linux/slab.h> #include <linux/sysfs.h> #define SUPPORTED_CABLE_MAX 32 #define CABLE_NAME_MAX 30 static const char *extcon_name[] = { [EXTCON_NONE] = "NONE", /* USB external connector */ [EXTCON_USB] = "USB", [EXTCON_USB_HOST] = "USB-HOST", /* Charging external connector */ [EXTCON_CHG_USB_SDP] = "SDP", [EXTCON_CHG_USB_DCP] = "DCP", [EXTCON_CHG_USB_CDP] = "CDP", [EXTCON_CHG_USB_ACA] = "ACA", [EXTCON_CHG_USB_FAST] = "FAST-CHARGER", [EXTCON_CHG_USB_SLOW] = "SLOW-CHARGER", /* Jack external connector */ [EXTCON_JACK_MICROPHONE] = "MICROPHONE", [EXTCON_JACK_HEADPHONE] = "HEADPHONE", [EXTCON_JACK_LINE_IN] = "LINE-IN", [EXTCON_JACK_LINE_OUT] = "LINE-OUT", [EXTCON_JACK_VIDEO_IN] = "VIDEO-IN", [EXTCON_JACK_VIDEO_OUT] = "VIDEO-OUT", [EXTCON_JACK_SPDIF_IN] = "SPDIF-IN", [EXTCON_JACK_SPDIF_OUT] = "SPDIF-OUT", /* Display external connector */ [EXTCON_DISP_HDMI] = "HDMI", [EXTCON_DISP_MHL] = "MHL", [EXTCON_DISP_DVI] = "DVI", [EXTCON_DISP_VGA] = "VGA", /* Miscellaneous external connector */ [EXTCON_DOCK] = "DOCK", [EXTCON_JIG] = "JIG", [EXTCON_MECHANICAL] = "MECHANICAL", NULL, }; /** * struct extcon_cable - An internal data for each cable of extcon device. * @edev: The extcon device * @cable_index: Index of this cable in the edev * @attr_g: Attribute group for the cable * @attr_name: "name" sysfs entry * @attr_state: "state" sysfs entry * @attrs: Array pointing to attr_name and attr_state for attr_g */ struct extcon_cable { struct extcon_dev *edev; int cable_index; struct attribute_group attr_g; struct device_attribute attr_name; struct device_attribute attr_state; struct attribute *attrs[3]; /* to be fed to attr_g.attrs */ }; static struct class *extcon_class; #if defined(CONFIG_ANDROID) static struct class_compat *switch_class; #endif /* CONFIG_ANDROID */ static LIST_HEAD(extcon_dev_list); static DEFINE_MUTEX(extcon_dev_list_lock); /** * check_mutually_exclusive - Check if new_state violates mutually_exclusive * condition. * @edev: the extcon device * @new_state: new cable attach status for @edev * * Returns 0 if nothing violates. Returns the index + 1 for the first * violated condition. */ static int check_mutually_exclusive(struct extcon_dev *edev, u32 new_state) { int i = 0; if (!edev->mutually_exclusive) return 0; for (i = 0; edev->mutually_exclusive[i]; i++) { int weight; u32 correspondants = new_state & edev->mutually_exclusive[i]; /* calculate the total number of bits set */ weight = hweight32(correspondants); if (weight > 1) return i + 1; } return 0; } static int find_cable_index_by_id(struct extcon_dev *edev, const unsigned int id) { int i; /* Find the the index of extcon cable in edev->supported_cable */ for (i = 0; i < edev->max_supported; i++) { if (edev->supported_cable[i] == id) return i; } return -EINVAL; } static bool is_extcon_changed(u32 prev, u32 new, int idx, bool *attached) { if (((prev >> idx) & 0x1) != ((new >> idx) & 0x1)) { *attached = ((new >> idx) & 0x1) ? true : false; return true; } return false; } static ssize_t state_show(struct device *dev, struct device_attribute *attr, char *buf) { int i, count = 0; struct extcon_dev *edev = dev_get_drvdata(dev); if (edev->max_supported == 0) return sprintf(buf, "%u\n", edev->state); for (i = 0; i < edev->max_supported; i++) { count += sprintf(buf + count, "%s=%d\n", extcon_name[edev->supported_cable[i]], !!(edev->state & (1 << i))); } return count; } static ssize_t state_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { u32 state; ssize_t ret = 0; struct extcon_dev *edev = dev_get_drvdata(dev); ret = sscanf(buf, "0x%x", &state); if (ret == 0) ret = -EINVAL; else ret = extcon_set_state(edev, state); if (ret < 0) return ret; return count; } static DEVICE_ATTR_RW(state); static ssize_t name_show(struct device *dev, struct device_attribute *attr, char *buf) { struct extcon_dev *edev = dev_get_drvdata(dev); return sprintf(buf, "%s\n", edev->name); } static DEVICE_ATTR_RO(name); static ssize_t cable_name_show(struct device *dev, struct device_attribute *attr, char *buf) { struct extcon_cable *cable = container_of(attr, struct extcon_cable, attr_name); int i = cable->cable_index; return sprintf(buf, "%s\n", extcon_name[cable->edev->supported_cable[i]]); } static ssize_t cable_state_show(struct device *dev, struct device_attribute *attr, char *buf) { struct extcon_cable *cable = container_of(attr, struct extcon_cable, attr_state); int i = cable->cable_index; return sprintf(buf, "%d\n", extcon_get_cable_state_(cable->edev, cable->edev->supported_cable[i])); } /** * extcon_update_state() - Update the cable attach states of the extcon device * only for the masked bits. * @edev: the extcon device * @mask: the bit mask to designate updated bits. * @state: new cable attach status for @edev * * Changing the state sends uevent with environment variable containing * the name of extcon device (envp[0]) and the state output (envp[1]). * Tizen uses this format for extcon device to get events from ports. * Android uses this format as well. * * Note that the notifier provides which bits are changed in the state * variable with the val parameter (second) to the callback. */ int extcon_update_state(struct extcon_dev *edev, u32 mask, u32 state) { char name_buf[120]; char state_buf[120]; char *prop_buf; char *envp[3]; int env_offset = 0; int length; int index; unsigned long flags; bool attached; if (!edev) return -EINVAL; spin_lock_irqsave(&edev->lock, flags); if (edev->state != ((edev->state & ~mask) | (state & mask))) { u32 old_state; if (check_mutually_exclusive(edev, (edev->state & ~mask) | (state & mask))) { spin_unlock_irqrestore(&edev->lock, flags); return -EPERM; } old_state = edev->state; edev->state &= ~mask; edev->state |= state & mask; for (index = 0; index < edev->max_supported; index++) { if (is_extcon_changed(old_state, edev->state, index, &attached)) raw_notifier_call_chain(&edev->nh[index], attached, edev); } /* This could be in interrupt handler */ prop_buf = (char *)get_zeroed_page(GFP_ATOMIC); if (prop_buf) { length = name_show(&edev->dev, NULL, prop_buf); if (length > 0) { if (prop_buf[length - 1] == '\n') prop_buf[length - 1] = 0; snprintf(name_buf, sizeof(name_buf), "NAME=%s", prop_buf); envp[env_offset++] = name_buf; } length = state_show(&edev->dev, NULL, prop_buf); if (length > 0) { if (prop_buf[length - 1] == '\n') prop_buf[length - 1] = 0; snprintf(state_buf, sizeof(state_buf), "STATE=%s", prop_buf); envp[env_offset++] = state_buf; } envp[env_offset] = NULL; /* Unlock early before uevent */ spin_unlock_irqrestore(&edev->lock, flags); kobject_uevent_env(&edev->dev.kobj, KOBJ_CHANGE, envp); free_page((unsigned long)prop_buf); } else { /* Unlock early before uevent */ spin_unlock_irqrestore(&edev->lock, flags); dev_err(&edev->dev, "out of memory in extcon_set_state\n"); kobject_uevent(&edev->dev.kobj, KOBJ_CHANGE); } } else { /* No changes */ spin_unlock_irqrestore(&edev->lock, flags); } return 0; } EXPORT_SYMBOL_GPL(extcon_update_state); /** * extcon_set_state() - Set the cable attach states of the extcon device. * @edev: the extcon device * @state: new cable attach status for @edev * * Note that notifier provides which bits are changed in the state * variable with the val parameter (second) to the callback. */ int extcon_set_state(struct extcon_dev *edev, u32 state) { if (!edev) return -EINVAL; return extcon_update_state(edev, 0xffffffff, state); } EXPORT_SYMBOL_GPL(extcon_set_state); /** * extcon_get_cable_state_() - Get the status of a specific cable. * @edev: the extcon device that has the cable. * @id: the unique id of each external connector in extcon enumeration. */ int extcon_get_cable_state_(struct extcon_dev *edev, const unsigned int id) { int index; if (!edev) return -EINVAL; index = find_cable_index_by_id(edev, id); if (index < 0) return index; if (edev->max_supported && edev->max_supported <= index) return -EINVAL; return !!(edev->state & (1 << index)); } EXPORT_SYMBOL_GPL(extcon_get_cable_state_); /** * extcon_set_cable_state_() - Set the status of a specific cable. * @edev: the extcon device that has the cable. * @id: the unique id of each external connector * in extcon enumeration. * @state: the new cable status. The default semantics is * true: attached / false: detached. */ int extcon_set_cable_state_(struct extcon_dev *edev, unsigned int id, bool cable_state) { u32 state; int index; if (!edev) return -EINVAL; index = find_cable_index_by_id(edev, id); if (index < 0) return index; if (edev->max_supported && edev->max_supported <= index) return -EINVAL; state = cable_state ? (1 << index) : 0; return extcon_update_state(edev, 1 << index, state); } EXPORT_SYMBOL_GPL(extcon_set_cable_state_); /** * extcon_get_extcon_dev() - Get the extcon device instance from the name * @extcon_name: The extcon name provided with extcon_dev_register() */ struct extcon_dev *extcon_get_extcon_dev(const char *extcon_name) { struct extcon_dev *sd; if (!extcon_name) return ERR_PTR(-EINVAL); mutex_lock(&extcon_dev_list_lock); list_for_each_entry(sd, &extcon_dev_list, entry) { if (!strcmp(sd->name, extcon_name)) goto out; } sd = NULL; out: mutex_unlock(&extcon_dev_list_lock); return sd; } EXPORT_SYMBOL_GPL(extcon_get_extcon_dev); /** * extcon_register_notifier() - Register a notifiee to get notified by * any attach status changes from the extcon. * @edev: the extcon device that has the external connecotr. * @id: the unique id of each external connector in extcon enumeration. * @nb: a notifier block to be registered. * * Note that the second parameter given to the callback of nb (val) is * "old_state", not the current state. The current state can be retrieved * by looking at the third pameter (edev pointer)'s state value. */ int extcon_register_notifier(struct extcon_dev *edev, unsigned int id, struct notifier_block *nb) { unsigned long flags; int ret, idx; if (!nb) return -EINVAL; if (edev) { idx = find_cable_index_by_id(edev, id); if (idx < 0) return idx; spin_lock_irqsave(&edev->lock, flags); ret = raw_notifier_chain_register(&edev->nh[idx], nb); spin_unlock_irqrestore(&edev->lock, flags); } else { struct extcon_dev *extd; mutex_lock(&extcon_dev_list_lock); list_for_each_entry(extd, &extcon_dev_list, entry) { idx = find_cable_index_by_id(extd, id); if (idx >= 0) break; } mutex_unlock(&extcon_dev_list_lock); if (idx >= 0) { edev = extd; return extcon_register_notifier(extd, id, nb); } else { ret = -ENODEV; } } return ret; } EXPORT_SYMBOL_GPL(extcon_register_notifier); /** * extcon_unregister_notifier() - Unregister a notifiee from the extcon device. * @edev: the extcon device that has the external connecotr. * @id: the unique id of each external connector in extcon enumeration. * @nb: a notifier block to be registered. */ int extcon_unregister_notifier(struct extcon_dev *edev, unsigned int id, struct notifier_block *nb) { unsigned long flags; int ret, idx; if (!edev || !nb) return -EINVAL; idx = find_cable_index_by_id(edev, id); if (idx < 0) return idx; spin_lock_irqsave(&edev->lock, flags); ret = raw_notifier_chain_unregister(&edev->nh[idx], nb); spin_unlock_irqrestore(&edev->lock, flags); return ret; } EXPORT_SYMBOL_GPL(extcon_unregister_notifier); static struct attribute *extcon_attrs[] = { &dev_attr_state.attr, &dev_attr_name.attr, NULL, }; ATTRIBUTE_GROUPS(extcon);