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extcon.c
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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 <[email protected]>
*
* Copyright (C) 2012 Samsung Electronics
* Author: Donggeun Kim <[email protected]>
* Author: MyungJoo Ham <[email protected]>
*
* based on android/drivers/switch/switch_class.c
* Copyright (C) 2008 Google, Inc.
* Author: Mike Lockwood <[email protected]>
*
* 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",
/* Charger external connector */
[EXTCON_TA] = "TA",
[EXTCON_FAST_CHARGER] = "FAST-CHARGER",
[EXTCON_SLOW_CHARGER] = "SLOW-CHARGER",
[EXTCON_CHARGE_DOWNSTREAM] = "CHARGE-DOWNSTREAM",
/* Audio/Video external connector */
[EXTCON_LINE_IN] = "LINE-IN",
[EXTCON_LINE_OUT] = "LINE-OUT",
[EXTCON_MICROPHONE] = "MICROPHONE",
[EXTCON_HEADPHONE] = "HEADPHONE",
[EXTCON_HDMI] = "HDMI",
[EXTCON_MHL] = "MHL",
[EXTCON_DVI] = "DVI",
[EXTCON_VGA] = "VGA",
[EXTCON_SPDIF_IN] = "SPDIF-IN",
[EXTCON_SPDIF_OUT] = "SPDIF-OUT",
[EXTCON_VIDEO_IN] = "VIDEO-IN",
[EXTCON_VIDEO_OUT] = "VIDEO-OUT",
/* Etc external connector */
[EXTCON_DOCK] = "DOCK",
[EXTCON_JIG] = "JIG",
[EXTCON_MECHANICAL] = "MECHANICAL",
NULL,
};
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 int find_cable_index_by_name(struct extcon_dev *edev, const char *name)
{
unsigned int id = EXTCON_NONE;
int i = 0;
if (edev->max_supported == 0)
return -EINVAL;
/* Find the the number of extcon cable */
while (extcon_name[i]) {
if (!strncmp(extcon_name[i], name, CABLE_NAME_MAX)) {
id = i;
break;
}
}
if (id == EXTCON_NONE)
return -EINVAL;
return find_cable_index_by_id(edev, id);
}
static bool is_extcon_changed(u32 prev, u32 new, int idx, bool *attached)
{
if (((prev >> idx) & 0x1) != ((new >> idx) & 0x1)) {
*attached = new ? 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->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 < 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);
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;
int index;
unsigned long flags;
bool attached;
spin_lock_irqsave(&edev->lock, flags);
if (edev->state != ((edev->state & ~mask) | (state & mask))) {
if (check_mutually_exclusive(edev, (edev->state & ~mask) |
(state & mask))) {
spin_unlock_irqrestore(&edev->lock, flags);
return -EPERM;
}
for (index = 0; index < edev->max_supported; index++) {
if (is_extcon_changed(edev->state, state, index, &attached))
raw_notifier_call_chain(&edev->nh[index], attached, edev);
}
edev->state &= ~mask;
edev->state |= state & mask;
/* 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_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;
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_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, find_cable_index_by_name
(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.
* @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;
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_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, find_cable_index_by_name
(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);
/**
* 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 = find_cable_index_by_name(obj->edev,
cable_name);
if (obj->cable_index < 0)
return obj->cable_index;
obj->user_nb = nb;
spin_lock_irqsave(&obj->edev->lock, flags);
ret = raw_notifier_chain_register(
&obj->edev->nh[obj->cable_index],
obj->user_nb);
spin_unlock_irqrestore(&obj->edev->lock, flags);
} 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 (find_cable_index_by_name(extd, cable_name) < 0)
continue;
class_dev_iter_exit(&iter);
return extcon_register_interest(obj, extd->name,
cable_name, nb);
}
ret = -ENODEV;
}
return ret;
}
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->cable_index], obj->user_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 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;
idx = find_cable_index_by_id(edev, id);
spin_lock_irqsave(&edev->lock, flags);
ret = raw_notifier_chain_register(&edev->nh[idx], 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 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;
idx = find_cable_index_by_id(edev, id);
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);
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 extcon ending with EXTCON_NONE.
* 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 unsigned int *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 extcon ending with EXTCON_NONE.
* 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 unsigned int *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;
static atomic_t edev_no = ATOMIC_INIT(-1);
if (!extcon_class) {
ret = create_extcon_class();
if (ret < 0)
return ret;
}
if (!edev->supported_cable)
return -EINVAL;
for (; edev->supported_cable[index] != EXTCON_NONE; index++);
edev->max_supported = index;
if (index > SUPPORTED_CABLE_MAX) {
dev_err(&edev->dev,
"exceed the maximum number of supported cables\n");
return -EINVAL;
}
edev->dev.class = extcon_class;
edev->dev.release = extcon_dev_release;
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, "extcon%lu",
(unsigned long)atomic_inc_return(&edev_no));
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);
edev->nh = devm_kzalloc(&edev->dev,
sizeof(*edev->nh) * edev->max_supported, GFP_KERNEL);
if (!edev->nh) {
ret = -ENOMEM;
goto err_dev;
}
for (index = 0; index < edev->max_supported; index++)
RAW_INIT_NOTIFIER_HEAD(&edev->nh[index]);
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;