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-rw-r--r--kernel/drivers/extcon/extcon.c1066
1 files changed, 1066 insertions, 0 deletions
diff --git a/kernel/drivers/extcon/extcon.c b/kernel/drivers/extcon/extcon.c
new file mode 100644
index 000000000..4c9f165e4
--- /dev/null
+++ b/kernel/drivers/extcon/extcon.c
@@ -0,0 +1,1066 @@
+/*
+ * drivers/extcon/extcon_class.c
+ *
+ * External connector (extcon) class driver
+ *
+ * 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>
+
+/*
+ * extcon_cable_name suggests the standard cable names for commonly used
+ * cable types.
+ *
+ * However, please do not use extcon_cable_name directly for extcon_dev
+ * struct's supported_cable pointer unless your device really supports
+ * every single port-type of the following cable names. Please choose cable
+ * names that are actually used in your extcon device.
+ */
+const char extcon_cable_name[][CABLE_NAME_MAX + 1] = {
+ [EXTCON_USB] = "USB",
+ [EXTCON_USB_HOST] = "USB-Host",
+ [EXTCON_TA] = "TA",
+ [EXTCON_FAST_CHARGER] = "Fast-charger",
+ [EXTCON_SLOW_CHARGER] = "Slow-charger",
+ [EXTCON_CHARGE_DOWNSTREAM] = "Charge-downstream",
+ [EXTCON_HDMI] = "HDMI",
+ [EXTCON_MHL] = "MHL",
+ [EXTCON_DVI] = "DVI",
+ [EXTCON_VGA] = "VGA",
+ [EXTCON_DOCK] = "Dock",
+ [EXTCON_LINE_IN] = "Line-in",
+ [EXTCON_LINE_OUT] = "Line-out",
+ [EXTCON_MIC_IN] = "Microphone",
+ [EXTCON_HEADPHONE_OUT] = "Headphone",
+ [EXTCON_SPDIF_IN] = "SPDIF-in",
+ [EXTCON_SPDIF_OUT] = "SPDIF-out",
+ [EXTCON_VIDEO_IN] = "Video-in",
+ [EXTCON_VIDEO_OUT] = "Video-out",
+ [EXTCON_MECHANICAL] = "Mechanical",
+};
+
+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 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->print_state) {
+ int ret = edev->print_state(edev, buf);
+
+ if (ret >= 0)
+ return ret;
+ /* Use default if failed */
+ }
+
+ if (edev->max_supported == 0)
+ return sprintf(buf, "%u\n", edev->state);
+
+ for (i = 0; i < SUPPORTED_CABLE_MAX; i++) {
+ if (!edev->supported_cable[i])
+ break;
+ count += sprintf(buf + count, "%s=%d\n",
+ 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);
+
+ /* Optional callback given by the user */
+ if (edev->print_name) {
+ int ret = edev->print_name(edev, buf);
+
+ if (ret >= 0)
+ return ret;
+ }
+
+ return sprintf(buf, "%s\n", dev_name(&edev->dev));
+}
+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);
+
+ return sprintf(buf, "%s\n",
+ cable->edev->supported_cable[cable->cable_index]);
+}
+
+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);
+
+ return sprintf(buf, "%d\n",
+ extcon_get_cable_state_(cable->edev,
+ cable->cable_index));
+}
+
+/**
+ * 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;
+ unsigned long flags;
+
+ spin_lock_irqsave(&edev->lock, flags);
+
+ if (edev->state != ((edev->state & ~mask) | (state & mask))) {
+ u32 old_state = edev->state;
+
+ if (check_mutually_exclusive(edev, (edev->state & ~mask) |
+ (state & mask))) {
+ spin_unlock_irqrestore(&edev->lock, flags);
+ return -EPERM;
+ }
+
+ edev->state &= ~mask;
+ edev->state |= state & mask;
+
+ raw_notifier_call_chain(&edev->nh, old_state, 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)
+{
+ return extcon_update_state(edev, 0xffffffff, state);
+}
+EXPORT_SYMBOL_GPL(extcon_set_state);
+
+/**
+ * extcon_find_cable_index() - Get the cable index based on the cable name.
+ * @edev: the extcon device that has the cable.
+ * @cable_name: cable name to be searched.
+ *
+ * Note that accessing a cable state based on cable_index is faster than
+ * cable_name because using cable_name induces a loop with strncmp().
+ * Thus, when get/set_cable_state is repeatedly used, using cable_index
+ * is recommended.
+ */
+int extcon_find_cable_index(struct extcon_dev *edev, const char *cable_name)
+{
+ int i;
+
+ if (edev->supported_cable) {
+ for (i = 0; edev->supported_cable[i]; i++) {
+ if (!strncmp(edev->supported_cable[i],
+ cable_name, CABLE_NAME_MAX))
+ return i;
+ }
+ }
+
+ return -EINVAL;
+}
+EXPORT_SYMBOL_GPL(extcon_find_cable_index);
+
+/**
+ * extcon_get_cable_state_() - Get the status of a specific cable.
+ * @edev: the extcon device that has the cable.
+ * @index: cable index that can be retrieved by extcon_find_cable_index().
+ */
+int extcon_get_cable_state_(struct extcon_dev *edev, int index)
+{
+ if (index < 0 || (edev->max_supported && edev->max_supported <= index))
+ return -EINVAL;
+
+ return !!(edev->state & (1 << index));
+}
+EXPORT_SYMBOL_GPL(extcon_get_cable_state_);
+
+/**
+ * extcon_get_cable_state() - Get the status of a specific cable.
+ * @edev: the extcon device that has the cable.
+ * @cable_name: cable name.
+ *
+ * Note that this is slower than extcon_get_cable_state_.
+ */
+int extcon_get_cable_state(struct extcon_dev *edev, const char *cable_name)
+{
+ return extcon_get_cable_state_(edev, extcon_find_cable_index
+ (edev, cable_name));
+}
+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.
+ * @index: cable index that can be retrieved by
+ * extcon_find_cable_index().
+ * @cable_state: the new cable status. The default semantics is
+ * true: attached / false: detached.
+ */
+int extcon_set_cable_state_(struct extcon_dev *edev,
+ int index, bool cable_state)
+{
+ u32 state;
+
+ if (index < 0 || (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_set_cable_state() - Set the status of a specific cable.
+ * @edev: the extcon device that has the cable.
+ * @cable_name: cable name.
+ * @cable_state: the new cable status. The default semantics is
+ * true: attached / false: detached.
+ *
+ * Note that this is slower than extcon_set_cable_state_.
+ */
+int extcon_set_cable_state(struct extcon_dev *edev,
+ const char *cable_name, bool cable_state)
+{
+ return extcon_set_cable_state_(edev, extcon_find_cable_index
+ (edev, cable_name), cable_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;
+
+ 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);
+
+static int _call_per_cable(struct notifier_block *nb, unsigned long val,
+ void *ptr)
+{
+ struct extcon_specific_cable_nb *obj = container_of(nb,
+ struct extcon_specific_cable_nb, internal_nb);
+ struct extcon_dev *edev = ptr;
+
+ if ((val & (1 << obj->cable_index)) !=
+ (edev->state & (1 << obj->cable_index))) {
+ bool cable_state = true;
+
+ obj->previous_value = val;
+
+ if (val & (1 << obj->cable_index))
+ cable_state = false;
+
+ return obj->user_nb->notifier_call(obj->user_nb,
+ cable_state, ptr);
+ }
+
+ return NOTIFY_OK;
+}
+
+/**
+ * extcon_register_interest() - Register a notifier for a state change of a
+ * specific cable, not an entier set of cables of a
+ * extcon device.
+ * @obj: an empty extcon_specific_cable_nb object to be returned.
+ * @extcon_name: the name of extcon device.
+ * if NULL, extcon_register_interest will register
+ * every cable with the target cable_name given.
+ * @cable_name: the target cable name.
+ * @nb: the notifier block to get notified.
+ *
+ * Provide an empty extcon_specific_cable_nb. extcon_register_interest() sets
+ * the struct for you.
+ *
+ * extcon_register_interest is a helper function for those who want to get
+ * notification for a single specific cable's status change. If a user wants
+ * to get notification for any changes of all cables of a extcon device,
+ * he/she should use the general extcon_register_notifier().
+ *
+ * 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_interest(struct extcon_specific_cable_nb *obj,
+ const char *extcon_name, const char *cable_name,
+ struct notifier_block *nb)
+{
+ unsigned long flags;
+ int ret;
+
+ if (!obj || !cable_name || !nb)
+ return -EINVAL;
+
+ if (extcon_name) {
+ obj->edev = extcon_get_extcon_dev(extcon_name);
+ if (!obj->edev)
+ return -ENODEV;
+
+ obj->cable_index = extcon_find_cable_index(obj->edev,
+ cable_name);
+ if (obj->cable_index < 0)
+ return obj->cable_index;
+
+ obj->user_nb = nb;
+
+ obj->internal_nb.notifier_call = _call_per_cable;
+
+ spin_lock_irqsave(&obj->edev->lock, flags);
+ ret = raw_notifier_chain_register(&obj->edev->nh,
+ &obj->internal_nb);
+ spin_unlock_irqrestore(&obj->edev->lock, flags);
+ return ret;
+ } else {
+ struct class_dev_iter iter;
+ struct extcon_dev *extd;
+ struct device *dev;
+
+ if (!extcon_class)
+ return -ENODEV;
+ class_dev_iter_init(&iter, extcon_class, NULL, NULL);
+ while ((dev = class_dev_iter_next(&iter))) {
+ extd = dev_get_drvdata(dev);
+
+ if (extcon_find_cable_index(extd, cable_name) < 0)
+ continue;
+
+ class_dev_iter_exit(&iter);
+ return extcon_register_interest(obj, extd->name,
+ cable_name, nb);
+ }
+
+ return -ENODEV;
+ }
+}
+EXPORT_SYMBOL_GPL(extcon_register_interest);
+
+/**
+ * extcon_unregister_interest() - Unregister the notifier registered by
+ * extcon_register_interest().
+ * @obj: the extcon_specific_cable_nb object returned by
+ * extcon_register_interest().
+ */
+int extcon_unregister_interest(struct extcon_specific_cable_nb *obj)
+{
+ unsigned long flags;
+ int ret;
+
+ if (!obj)
+ return -EINVAL;
+
+ spin_lock_irqsave(&obj->edev->lock, flags);
+ ret = raw_notifier_chain_unregister(&obj->edev->nh, &obj->internal_nb);
+ spin_unlock_irqrestore(&obj->edev->lock, flags);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(extcon_unregister_interest);
+
+/**
+ * extcon_register_notifier() - Register a notifiee to get notified by
+ * any attach status changes from the extcon.
+ * @edev: the extcon device.
+ * @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,
+ struct notifier_block *nb)
+{
+ unsigned long flags;
+ int ret;
+
+ spin_lock_irqsave(&edev->lock, flags);
+ ret = raw_notifier_chain_register(&edev->nh, nb);
+ spin_unlock_irqrestore(&edev->lock, flags);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(extcon_register_notifier);
+
+/**
+ * extcon_unregister_notifier() - Unregister a notifiee from the extcon device.
+ * @edev: the extcon device.
+ * @nb: a registered notifier block to be unregistered.
+ */
+int extcon_unregister_notifier(struct extcon_dev *edev,
+ struct notifier_block *nb)
+{
+ unsigned long flags;
+ int ret;
+
+ spin_lock_irqsave(&edev->lock, flags);
+ ret = raw_notifier_chain_unregister(&edev->nh, 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);
+
+static int create_extcon_class(void)
+{
+ if (!extcon_class) {
+ extcon_class = class_create(THIS_MODULE, "extcon");
+ if (IS_ERR(extcon_class))
+ return PTR_ERR(extcon_class);
+ extcon_class->dev_groups = extcon_groups;
+
+#if defined(CONFIG_ANDROID)
+ switch_class = class_compat_register("switch");
+ if (WARN(!switch_class, "cannot allocate"))
+ return -ENOMEM;
+#endif /* CONFIG_ANDROID */
+ }
+
+ return 0;
+}
+
+static void extcon_dev_release(struct device *dev)
+{
+}
+
+static const char *muex_name = "mutually_exclusive";
+static void dummy_sysfs_dev_release(struct device *dev)
+{
+}
+
+/*
+ * extcon_dev_allocate() - Allocate the memory of extcon device.
+ * @supported_cable: Array of supported cable names ending with NULL.
+ * If supported_cable is NULL, cable name related APIs
+ * are disabled.
+ *
+ * This function allocates the memory for extcon device without allocating
+ * memory in each extcon provider driver and initialize default setting for
+ * extcon device.
+ *
+ * Return the pointer of extcon device if success or ERR_PTR(err) if fail
+ */
+struct extcon_dev *extcon_dev_allocate(const char **supported_cable)
+{
+ struct extcon_dev *edev;
+
+ edev = kzalloc(sizeof(*edev), GFP_KERNEL);
+ if (!edev)
+ return ERR_PTR(-ENOMEM);
+
+ edev->max_supported = 0;
+ edev->supported_cable = supported_cable;
+
+ return edev;
+}
+
+/*
+ * extcon_dev_free() - Free the memory of extcon device.
+ * @edev: the extcon device to free
+ */
+void extcon_dev_free(struct extcon_dev *edev)
+{
+ kfree(edev);
+}
+EXPORT_SYMBOL_GPL(extcon_dev_free);
+
+static int devm_extcon_dev_match(struct device *dev, void *res, void *data)
+{
+ struct extcon_dev **r = res;
+
+ if (WARN_ON(!r || !*r))
+ return 0;
+
+ return *r == data;
+}
+
+static void devm_extcon_dev_release(struct device *dev, void *res)
+{
+ extcon_dev_free(*(struct extcon_dev **)res);
+}
+
+/**
+ * devm_extcon_dev_allocate - Allocate managed extcon device
+ * @dev: device owning the extcon device being created
+ * @supported_cable: Array of supported cable names ending with NULL.
+ * If supported_cable is NULL, cable name related APIs
+ * are disabled.
+ *
+ * This function manages automatically the memory of extcon device using device
+ * resource management and simplify the control of freeing the memory of extcon
+ * device.
+ *
+ * Returns the pointer memory of allocated extcon_dev if success
+ * or ERR_PTR(err) if fail
+ */
+struct extcon_dev *devm_extcon_dev_allocate(struct device *dev,
+ const char **supported_cable)
+{
+ struct extcon_dev **ptr, *edev;
+
+ ptr = devres_alloc(devm_extcon_dev_release, sizeof(*ptr), GFP_KERNEL);
+ if (!ptr)
+ return ERR_PTR(-ENOMEM);
+
+ edev = extcon_dev_allocate(supported_cable);
+ if (IS_ERR(edev)) {
+ devres_free(ptr);
+ return edev;
+ }
+
+ edev->dev.parent = dev;
+
+ *ptr = edev;
+ devres_add(dev, ptr);
+
+ return edev;
+}
+EXPORT_SYMBOL_GPL(devm_extcon_dev_allocate);
+
+void devm_extcon_dev_free(struct device *dev, struct extcon_dev *edev)
+{
+ WARN_ON(devres_release(dev, devm_extcon_dev_release,
+ devm_extcon_dev_match, edev));
+}
+EXPORT_SYMBOL_GPL(devm_extcon_dev_free);
+
+/**
+ * extcon_dev_register() - Register a new extcon device
+ * @edev : the new extcon device (should be allocated before calling)
+ *
+ * Among the members of edev struct, please set the "user initializing data"
+ * in any case and set the "optional callbacks" if required. However, please
+ * do not set the values of "internal data", which are initialized by
+ * this function.
+ */
+int extcon_dev_register(struct extcon_dev *edev)
+{
+ int ret, index = 0;
+
+ if (!extcon_class) {
+ ret = create_extcon_class();
+ if (ret < 0)
+ return ret;
+ }
+
+ if (edev->supported_cable) {
+ /* Get size of array */
+ for (index = 0; edev->supported_cable[index]; index++)
+ ;
+ edev->max_supported = index;
+ } else {
+ edev->max_supported = 0;
+ }
+
+ if (index > SUPPORTED_CABLE_MAX) {
+ dev_err(&edev->dev, "extcon: maximum number of supported cables exceeded.\n");
+ return -EINVAL;
+ }
+
+ edev->dev.class = extcon_class;
+ edev->dev.release = extcon_dev_release;
+
+ edev->name = edev->name ? edev->name : dev_name(edev->dev.parent);
+ if (IS_ERR_OR_NULL(edev->name)) {
+ dev_err(&edev->dev,
+ "extcon device name is null\n");
+ return -EINVAL;
+ }
+ dev_set_name(&edev->dev, "%s", edev->name);
+
+ if (edev->max_supported) {
+ char buf[10];
+ char *str;
+ struct extcon_cable *cable;
+
+ edev->cables = kzalloc(sizeof(struct extcon_cable) *
+ edev->max_supported, GFP_KERNEL);
+ if (!edev->cables) {
+ ret = -ENOMEM;
+ goto err_sysfs_alloc;
+ }
+ for (index = 0; index < edev->max_supported; index++) {
+ cable = &edev->cables[index];
+
+ snprintf(buf, 10, "cable.%d", index);
+ str = kzalloc(sizeof(char) * (strlen(buf) + 1),
+ GFP_KERNEL);
+ if (!str) {
+ for (index--; index >= 0; index--) {
+ cable = &edev->cables[index];
+ kfree(cable->attr_g.name);
+ }
+ ret = -ENOMEM;
+
+ goto err_alloc_cables;
+ }
+ strcpy(str, buf);
+
+ cable->edev = edev;
+ cable->cable_index = index;
+ cable->attrs[0] = &cable->attr_name.attr;
+ cable->attrs[1] = &cable->attr_state.attr;
+ cable->attrs[2] = NULL;
+ cable->attr_g.name = str;
+ cable->attr_g.attrs = cable->attrs;
+
+ sysfs_attr_init(&cable->attr_name.attr);
+ cable->attr_name.attr.name = "name";
+ cable->attr_name.attr.mode = 0444;
+ cable->attr_name.show = cable_name_show;
+
+ sysfs_attr_init(&cable->attr_state.attr);
+ cable->attr_state.attr.name = "state";
+ cable->attr_state.attr.mode = 0444;
+ cable->attr_state.show = cable_state_show;
+ }
+ }
+
+ if (edev->max_supported && edev->mutually_exclusive) {
+ char buf[80];
+ char *name;
+
+ /* Count the size of mutually_exclusive array */
+ for (index = 0; edev->mutually_exclusive[index]; index++)
+ ;
+
+ edev->attrs_muex = kzalloc(sizeof(struct attribute *) *
+ (index + 1), GFP_KERNEL);
+ if (!edev->attrs_muex) {
+ ret = -ENOMEM;
+ goto err_muex;
+ }
+
+ edev->d_attrs_muex = kzalloc(sizeof(struct device_attribute) *
+ index, GFP_KERNEL);
+ if (!edev->d_attrs_muex) {
+ ret = -ENOMEM;
+ kfree(edev->attrs_muex);
+ goto err_muex;
+ }
+
+ for (index = 0; edev->mutually_exclusive[index]; index++) {
+ sprintf(buf, "0x%x", edev->mutually_exclusive[index]);
+ name = kzalloc(sizeof(char) * (strlen(buf) + 1),
+ GFP_KERNEL);
+ if (!name) {
+ for (index--; index >= 0; index--) {
+ kfree(edev->d_attrs_muex[index].attr.
+ name);
+ }
+ kfree(edev->d_attrs_muex);
+ kfree(edev->attrs_muex);
+ ret = -ENOMEM;
+ goto err_muex;
+ }
+ strcpy(name, buf);
+ sysfs_attr_init(&edev->d_attrs_muex[index].attr);
+ edev->d_attrs_muex[index].attr.name = name;
+ edev->d_attrs_muex[index].attr.mode = 0000;
+ edev->attrs_muex[index] = &edev->d_attrs_muex[index]
+ .attr;
+ }
+ edev->attr_g_muex.name = muex_name;
+ edev->attr_g_muex.attrs = edev->attrs_muex;
+
+ }
+
+ if (edev->max_supported) {
+ edev->extcon_dev_type.groups =
+ kzalloc(sizeof(struct attribute_group *) *
+ (edev->max_supported + 2), GFP_KERNEL);
+ if (!edev->extcon_dev_type.groups) {
+ ret = -ENOMEM;
+ goto err_alloc_groups;
+ }
+
+ edev->extcon_dev_type.name = dev_name(&edev->dev);
+ edev->extcon_dev_type.release = dummy_sysfs_dev_release;
+
+ for (index = 0; index < edev->max_supported; index++)
+ edev->extcon_dev_type.groups[index] =
+ &edev->cables[index].attr_g;
+ if (edev->mutually_exclusive)
+ edev->extcon_dev_type.groups[index] =
+ &edev->attr_g_muex;
+
+ edev->dev.type = &edev->extcon_dev_type;
+ }
+
+ ret = device_register(&edev->dev);
+ if (ret) {
+ put_device(&edev->dev);
+ goto err_dev;
+ }
+#if defined(CONFIG_ANDROID)
+ if (switch_class)
+ ret = class_compat_create_link(switch_class, &edev->dev, NULL);
+#endif /* CONFIG_ANDROID */
+
+ spin_lock_init(&edev->lock);
+
+ RAW_INIT_NOTIFIER_HEAD(&edev->nh);
+
+ dev_set_drvdata(&edev->dev, edev);
+ edev->state = 0;
+
+ mutex_lock(&extcon_dev_list_lock);
+ list_add(&edev->entry, &extcon_dev_list);
+ mutex_unlock(&extcon_dev_list_lock);
+
+ return 0;
+
+err_dev:
+ if (edev->max_supported)
+ kfree(edev->extcon_dev_type.groups);
+err_alloc_groups:
+ if (edev->max_supported && edev->mutually_exclusive) {
+ for (index = 0; edev->mutually_exclusive[index]; index++)
+ kfree(edev->d_attrs_muex[index].attr.name);
+ kfree(edev->d_attrs_muex);
+ kfree(edev->attrs_muex);
+ }
+err_muex:
+ for (index = 0; index < edev->max_supported; index++)
+ kfree(edev->cables[index].attr_g.name);
+err_alloc_cables:
+ if (edev->max_supported)
+ kfree(edev->cables);
+err_sysfs_alloc:
+ return ret;
+}
+EXPORT_SYMBOL_GPL(extcon_dev_register);
+
+/**
+ * extcon_dev_unregister() - Unregister the extcon device.
+ * @edev: the extcon device instance to be unregistered.
+ *
+ * Note that this does not call kfree(edev) because edev was not allocated
+ * by this class.
+ */
+void extcon_dev_unregister(struct extcon_dev *edev)
+{
+ int index;
+
+ mutex_lock(&extcon_dev_list_lock);
+ list_del(&edev->entry);
+ mutex_unlock(&extcon_dev_list_lock);
+
+ if (IS_ERR_OR_NULL(get_device(&edev->dev))) {
+ dev_err(&edev->dev, "Failed to unregister extcon_dev (%s)\n",
+ dev_name(&edev->dev));
+ return;
+ }
+
+ device_unregister(&edev->dev);
+
+ if (edev->mutually_exclusive && edev->max_supported) {
+ for (index = 0; edev->mutually_exclusive[index];
+ index++)
+ kfree(edev->d_attrs_muex[index].attr.name);
+ kfree(edev->d_attrs_muex);
+ kfree(edev->attrs_muex);
+ }
+
+ for (index = 0; index < edev->max_supported; index++)
+ kfree(edev->cables[index].attr_g.name);
+
+ if (edev->max_supported) {
+ kfree(edev->extcon_dev_type.groups);
+ kfree(edev->cables);
+ }
+
+#if defined(CONFIG_ANDROID)
+ if (switch_class)
+ class_compat_remove_link(switch_class, &edev->dev, NULL);
+#endif
+ put_device(&edev->dev);
+}
+EXPORT_SYMBOL_GPL(extcon_dev_unregister);
+
+static void devm_extcon_dev_unreg(struct device *dev, void *res)
+{
+ extcon_dev_unregister(*(struct extcon_dev **)res);
+}
+
+/**
+ * devm_extcon_dev_register() - Resource-managed extcon_dev_register()
+ * @dev: device to allocate extcon device
+ * @edev: the new extcon device to register
+ *
+ * Managed extcon_dev_register() function. If extcon device is attached with
+ * this function, that extcon device is automatically unregistered on driver
+ * detach. Internally this function calls extcon_dev_register() function.
+ * To get more information, refer that function.
+ *
+ * If extcon device is registered with this function and the device needs to be
+ * unregistered separately, devm_extcon_dev_unregister() should be used.
+ *
+ * Returns 0 if success or negaive error number if failure.
+ */
+int devm_extcon_dev_register(struct device *dev, struct extcon_dev *edev)
+{
+ struct extcon_dev **ptr;
+ int ret;
+
+ ptr = devres_alloc(devm_extcon_dev_unreg, sizeof(*ptr), GFP_KERNEL);
+ if (!ptr)
+ return -ENOMEM;
+
+ ret = extcon_dev_register(edev);
+ if (ret) {
+ devres_free(ptr);
+ return ret;
+ }
+
+ *ptr = edev;
+ devres_add(dev, ptr);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(devm_extcon_dev_register);
+
+/**
+ * devm_extcon_dev_unregister() - Resource-managed extcon_dev_unregister()
+ * @dev: device the extcon belongs to
+ * @edev: the extcon device to unregister
+ *
+ * Unregister extcon device that is registered with devm_extcon_dev_register()
+ * function.
+ */
+void devm_extcon_dev_unregister(struct device *dev, struct extcon_dev *edev)
+{
+ WARN_ON(devres_release(dev, devm_extcon_dev_unreg,
+ devm_extcon_dev_match, edev));
+}
+EXPORT_SYMBOL_GPL(devm_extcon_dev_unregister);
+
+#ifdef CONFIG_OF
+/*
+ * extcon_get_edev_by_phandle - Get the extcon device from devicetree
+ * @dev - instance to the given device
+ * @index - index into list of extcon_dev
+ *
+ * return the instance of extcon device
+ */
+struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev, int index)
+{
+ struct device_node *node;
+ struct extcon_dev *edev;
+
+ if (!dev->of_node) {
+ dev_err(dev, "device does not have a device node entry\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ node = of_parse_phandle(dev->of_node, "extcon", index);
+ if (!node) {
+ dev_err(dev, "failed to get phandle in %s node\n",
+ dev->of_node->full_name);
+ return ERR_PTR(-ENODEV);
+ }
+
+ mutex_lock(&extcon_dev_list_lock);
+ list_for_each_entry(edev, &extcon_dev_list, entry) {
+ if (edev->dev.parent && edev->dev.parent->of_node == node) {
+ mutex_unlock(&extcon_dev_list_lock);
+ return edev;
+ }
+ }
+ mutex_unlock(&extcon_dev_list_lock);
+
+ return ERR_PTR(-EPROBE_DEFER);
+}
+#else
+struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev, int index)
+{
+ return ERR_PTR(-ENOSYS);
+}
+#endif /* CONFIG_OF */
+EXPORT_SYMBOL_GPL(extcon_get_edev_by_phandle);
+
+static int __init extcon_class_init(void)
+{
+ return create_extcon_class();
+}
+module_init(extcon_class_init);
+
+static void __exit extcon_class_exit(void)
+{
+#if defined(CONFIG_ANDROID)
+ class_compat_unregister(switch_class);
+#endif
+ class_destroy(extcon_class);
+}
+module_exit(extcon_class_exit);
+
+MODULE_AUTHOR("Mike Lockwood <lockwood@android.com>");
+MODULE_AUTHOR("Donggeun Kim <dg77.kim@samsung.com>");
+MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
+MODULE_DESCRIPTION("External connector (extcon) class driver");
+MODULE_LICENSE("GPL");