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linux/drivers/extcon/extcon.c
Colin Ian King 1fa80f1827 extcon: remove redundant assignment to variable idx 
The variable idx is being initialized with a value that is never read
and it is being updated later with a new value.  The initialization is
redundant and can be removed.

Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2020-05-29 17:36:01 +09:00

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// SPDX-License-Identifier: GPL-2.0-only
/*
* drivers/extcon/extcon.c - External Connector (extcon) framework.
*
* 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>
*/
#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/of.h>
#include <linux/slab.h>
#include <linux/sysfs.h>
#include "extcon.h"
#define SUPPORTED_CABLE_MAX 32
static const struct __extcon_info {
unsigned int type;
unsigned int id;
const char *name;
} extcon_info[] = {
[EXTCON_NONE] = {
.type = EXTCON_TYPE_MISC,
.id = EXTCON_NONE,
.name = "NONE",
},
/* USB external connector */
[EXTCON_USB] = {
.type = EXTCON_TYPE_USB,
.id = EXTCON_USB,
.name = "USB",
},
[EXTCON_USB_HOST] = {
.type = EXTCON_TYPE_USB,
.id = EXTCON_USB_HOST,
.name = "USB-HOST",
},
/* Charging external connector */
[EXTCON_CHG_USB_SDP] = {
.type = EXTCON_TYPE_CHG | EXTCON_TYPE_USB,
.id = EXTCON_CHG_USB_SDP,
.name = "SDP",
},
[EXTCON_CHG_USB_DCP] = {
.type = EXTCON_TYPE_CHG | EXTCON_TYPE_USB,
.id = EXTCON_CHG_USB_DCP,
.name = "DCP",
},
[EXTCON_CHG_USB_CDP] = {
.type = EXTCON_TYPE_CHG | EXTCON_TYPE_USB,
.id = EXTCON_CHG_USB_CDP,
.name = "CDP",
},
[EXTCON_CHG_USB_ACA] = {
.type = EXTCON_TYPE_CHG | EXTCON_TYPE_USB,
.id = EXTCON_CHG_USB_ACA,
.name = "ACA",
},
[EXTCON_CHG_USB_FAST] = {
.type = EXTCON_TYPE_CHG | EXTCON_TYPE_USB,
.id = EXTCON_CHG_USB_FAST,
.name = "FAST-CHARGER",
},
[EXTCON_CHG_USB_SLOW] = {
.type = EXTCON_TYPE_CHG | EXTCON_TYPE_USB,
.id = EXTCON_CHG_USB_SLOW,
.name = "SLOW-CHARGER",
},
[EXTCON_CHG_WPT] = {
.type = EXTCON_TYPE_CHG,
.id = EXTCON_CHG_WPT,
.name = "WPT",
},
[EXTCON_CHG_USB_PD] = {
.type = EXTCON_TYPE_CHG | EXTCON_TYPE_USB,
.id = EXTCON_CHG_USB_PD,
.name = "PD",
},
/* Jack external connector */
[EXTCON_JACK_MICROPHONE] = {
.type = EXTCON_TYPE_JACK,
.id = EXTCON_JACK_MICROPHONE,
.name = "MICROPHONE",
},
[EXTCON_JACK_HEADPHONE] = {
.type = EXTCON_TYPE_JACK,
.id = EXTCON_JACK_HEADPHONE,
.name = "HEADPHONE",
},
[EXTCON_JACK_LINE_IN] = {
.type = EXTCON_TYPE_JACK,
.id = EXTCON_JACK_LINE_IN,
.name = "LINE-IN",
},
[EXTCON_JACK_LINE_OUT] = {
.type = EXTCON_TYPE_JACK,
.id = EXTCON_JACK_LINE_OUT,
.name = "LINE-OUT",
},
[EXTCON_JACK_VIDEO_IN] = {
.type = EXTCON_TYPE_JACK,
.id = EXTCON_JACK_VIDEO_IN,
.name = "VIDEO-IN",
},
[EXTCON_JACK_VIDEO_OUT] = {
.type = EXTCON_TYPE_JACK,
.id = EXTCON_JACK_VIDEO_OUT,
.name = "VIDEO-OUT",
},
[EXTCON_JACK_SPDIF_IN] = {
.type = EXTCON_TYPE_JACK,
.id = EXTCON_JACK_SPDIF_IN,
.name = "SPDIF-IN",
},
[EXTCON_JACK_SPDIF_OUT] = {
.type = EXTCON_TYPE_JACK,
.id = EXTCON_JACK_SPDIF_OUT,
.name = "SPDIF-OUT",
},
/* Display external connector */
[EXTCON_DISP_HDMI] = {
.type = EXTCON_TYPE_DISP,
.id = EXTCON_DISP_HDMI,
.name = "HDMI",
},
[EXTCON_DISP_MHL] = {
.type = EXTCON_TYPE_DISP,
.id = EXTCON_DISP_MHL,
.name = "MHL",
},
[EXTCON_DISP_DVI] = {
.type = EXTCON_TYPE_DISP,
.id = EXTCON_DISP_DVI,
.name = "DVI",
},
[EXTCON_DISP_VGA] = {
.type = EXTCON_TYPE_DISP,
.id = EXTCON_DISP_VGA,
.name = "VGA",
},
[EXTCON_DISP_DP] = {
.type = EXTCON_TYPE_DISP | EXTCON_TYPE_USB,
.id = EXTCON_DISP_DP,
.name = "DP",
},
[EXTCON_DISP_HMD] = {
.type = EXTCON_TYPE_DISP | EXTCON_TYPE_USB,
.id = EXTCON_DISP_HMD,
.name = "HMD",
},
/* Miscellaneous external connector */
[EXTCON_DOCK] = {
.type = EXTCON_TYPE_MISC,
.id = EXTCON_DOCK,
.name = "DOCK",
},
[EXTCON_JIG] = {
.type = EXTCON_TYPE_MISC,
.id = EXTCON_JIG,
.name = "JIG",
},
[EXTCON_MECHANICAL] = {
.type = EXTCON_TYPE_MISC,
.id = EXTCON_MECHANICAL,
.name = "MECHANICAL",
},
{ /* sentinel */ }
};
/**
* struct extcon_cable - An internal data for an external connector.
* @edev: the extcon device
* @cable_index: the index of this cable in the edev
* @attr_g: the attribute group for the cable
* @attr_name: "name" sysfs entry
* @attr_state: "state" sysfs entry
* @attrs: the 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 */
union extcon_property_value usb_propval[EXTCON_PROP_USB_CNT];
union extcon_property_value chg_propval[EXTCON_PROP_CHG_CNT];
union extcon_property_value jack_propval[EXTCON_PROP_JACK_CNT];
union extcon_property_value disp_propval[EXTCON_PROP_DISP_CNT];
unsigned long usb_bits[BITS_TO_LONGS(EXTCON_PROP_USB_CNT)];
unsigned long chg_bits[BITS_TO_LONGS(EXTCON_PROP_CHG_CNT)];
unsigned long jack_bits[BITS_TO_LONGS(EXTCON_PROP_JACK_CNT)];
unsigned long disp_bits[BITS_TO_LONGS(EXTCON_PROP_DISP_CNT)];
};
static struct class *extcon_class;
static LIST_HEAD(extcon_dev_list);
static DEFINE_MUTEX(extcon_dev_list_lock);
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 get_extcon_type(unsigned int prop)
{
switch (prop) {
case EXTCON_PROP_USB_MIN ... EXTCON_PROP_USB_MAX:
return EXTCON_TYPE_USB;
case EXTCON_PROP_CHG_MIN ... EXTCON_PROP_CHG_MAX:
return EXTCON_TYPE_CHG;
case EXTCON_PROP_JACK_MIN ... EXTCON_PROP_JACK_MAX:
return EXTCON_TYPE_JACK;
case EXTCON_PROP_DISP_MIN ... EXTCON_PROP_DISP_MAX:
return EXTCON_TYPE_DISP;
default:
return -EINVAL;
}
}
static bool is_extcon_attached(struct extcon_dev *edev, unsigned int index)
{
return !!(edev->state & BIT(index));
}
static bool is_extcon_changed(struct extcon_dev *edev, int index,
bool new_state)
{
int state = !!(edev->state & BIT(index));
return (state != new_state);
}
static bool is_extcon_property_supported(unsigned int id, unsigned int prop)
{
int type;
/* Check whether the property is supported or not. */
type = get_extcon_type(prop);
if (type < 0)
return false;
/* Check whether a specific extcon id supports the property or not. */
return !!(extcon_info[id].type & type);
}
static int is_extcon_property_capability(struct extcon_dev *edev,
unsigned int id, int index,unsigned int prop)
{
struct extcon_cable *cable;
int type, ret;
/* Check whether the property is supported or not. */
type = get_extcon_type(prop);
if (type < 0)
return type;
cable = &edev->cables[index];
switch (type) {
case EXTCON_TYPE_USB:
ret = test_bit(prop - EXTCON_PROP_USB_MIN, cable->usb_bits);
break;
case EXTCON_TYPE_CHG:
ret = test_bit(prop - EXTCON_PROP_CHG_MIN, cable->chg_bits);
break;
case EXTCON_TYPE_JACK:
ret = test_bit(prop - EXTCON_PROP_JACK_MIN, cable->jack_bits);
break;
case EXTCON_TYPE_DISP:
ret = test_bit(prop - EXTCON_PROP_DISP_MIN, cable->disp_bits);
break;
default:
ret = -EINVAL;
}
return ret;
}
static void init_property(struct extcon_dev *edev, unsigned int id, int index)
{
unsigned int type = extcon_info[id].type;
struct extcon_cable *cable = &edev->cables[index];
if (EXTCON_TYPE_USB & type)
memset(cable->usb_propval, 0, sizeof(cable->usb_propval));
if (EXTCON_TYPE_CHG & type)
memset(cable->chg_propval, 0, sizeof(cable->chg_propval));
if (EXTCON_TYPE_JACK & type)
memset(cable->jack_propval, 0, sizeof(cable->jack_propval));
if (EXTCON_TYPE_DISP & type)
memset(cable->disp_propval, 0, sizeof(cable->disp_propval));
}
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_info[edev->supported_cable[i]].name,
!!(edev->state & BIT(i)));
}
return count;
}
static DEVICE_ATTR_RO(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_info[cable->edev->supported_cable[i]].name);
}
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_state(cable->edev, cable->edev->supported_cable[i]));
}
/**
* extcon_sync() - Synchronize the state for an external connector.
* @edev: the extcon device
*
* Note that this function send a notification in order to synchronize
* the state and property of an external connector.
*
* Returns 0 if success or error number if fail.
*/
int extcon_sync(struct extcon_dev *edev, unsigned int id)
{
char name_buf[120];
char state_buf[120];
char *prop_buf;
char *envp[3];
int env_offset = 0;
int length;
int index;
int state;
unsigned long flags;
if (!edev)
return -EINVAL;
index = find_cable_index_by_id(edev, id);
if (index < 0)
return index;
spin_lock_irqsave(&edev->lock, flags);
state = !!(edev->state & BIT(index));
spin_unlock_irqrestore(&edev->lock, flags);
/*
* Call functions in a raw notifier chain for the specific one
* external connector.
*/
raw_notifier_call_chain(&edev->nh[index], state, edev);
/*
* Call functions in a raw notifier chain for the all supported
* external connectors.
*/
raw_notifier_call_chain(&edev->nh_all, state, edev);
spin_lock_irqsave(&edev->lock, flags);
/* This could be in interrupt handler */
prop_buf = (char *)get_zeroed_page(GFP_ATOMIC);
if (!prop_buf) {
/* 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);
return -ENOMEM;
}
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);
return 0;
}
EXPORT_SYMBOL_GPL(extcon_sync);
/**
* extcon_get_state() - Get the state of an external connector.
* @edev: the extcon device
* @id: the unique id indicating an external connector
*
* Returns 0 if success or error number if fail.
*/
int extcon_get_state(struct extcon_dev *edev, const unsigned int id)
{
int index, state;
unsigned long flags;
if (!edev)
return -EINVAL;
index = find_cable_index_by_id(edev, id);
if (index < 0)
return index;
spin_lock_irqsave(&edev->lock, flags);
state = is_extcon_attached(edev, index);
spin_unlock_irqrestore(&edev->lock, flags);
return state;
}
EXPORT_SYMBOL_GPL(extcon_get_state);
/**
* extcon_set_state() - Set the state of an external connector.
* @edev: the extcon device
* @id: the unique id indicating an external connector
* @state: the new state of an external connector.
* the default semantics is true: attached / false: detached.
*
* Note that this function set the state of an external connector without
* a notification. To synchronize the state of an external connector,
* have to use extcon_set_state_sync() and extcon_sync().
*
* Returns 0 if success or error number if fail.
*/
int extcon_set_state(struct extcon_dev *edev, unsigned int id, bool state)
{
unsigned long flags;
int index, ret = 0;
if (!edev)
return -EINVAL;
index = find_cable_index_by_id(edev, id);
if (index < 0)
return index;
spin_lock_irqsave(&edev->lock, flags);
/* Check whether the external connector's state is changed. */
if (!is_extcon_changed(edev, index, state))
goto out;
if (check_mutually_exclusive(edev,
(edev->state & ~BIT(index)) | (state & BIT(index)))) {
ret = -EPERM;
goto out;
}
/*
* Initialize the value of extcon property before setting
* the detached state for an external connector.
*/
if (!state)
init_property(edev, id, index);
/* Update the state for an external connector. */
if (state)
edev->state |= BIT(index);
else
edev->state &= ~(BIT(index));
out:
spin_unlock_irqrestore(&edev->lock, flags);
return ret;
}
EXPORT_SYMBOL_GPL(extcon_set_state);
/**
* extcon_set_state_sync() - Set the state of an external connector with sync.
* @edev: the extcon device
* @id: the unique id indicating an external connector
* @state: the new state of external connector.
* the default semantics is true: attached / false: detached.
*
* Note that this function set the state of external connector
* and synchronize the state by sending a notification.
*
* Returns 0 if success or error number if fail.
*/
int extcon_set_state_sync(struct extcon_dev *edev, unsigned int id, bool state)
{
int ret, index;
unsigned long flags;
index = find_cable_index_by_id(edev, id);
if (index < 0)
return index;
/* Check whether the external connector's state is changed. */
spin_lock_irqsave(&edev->lock, flags);
ret = is_extcon_changed(edev, index, state);
spin_unlock_irqrestore(&edev->lock, flags);
if (!ret)
return 0;
ret = extcon_set_state(edev, id, state);
if (ret < 0)
return ret;
return extcon_sync(edev, id);
}
EXPORT_SYMBOL_GPL(extcon_set_state_sync);
/**
* extcon_get_property() - Get the property value of an external connector.
* @edev: the extcon device
* @id: the unique id indicating an external connector
* @prop: the property id indicating an extcon property
* @prop_val: the pointer which store the value of extcon property
*
* Note that when getting the property value of external connector,
* the external connector should be attached. If detached state, function
* return 0 without property value. Also, the each property should be
* included in the list of supported properties according to extcon type.
*
* Returns 0 if success or error number if fail.
*/
int extcon_get_property(struct extcon_dev *edev, unsigned int id,
unsigned int prop,
union extcon_property_value *prop_val)
{
struct extcon_cable *cable;
unsigned long flags;
int index, ret = 0;
*prop_val = (union extcon_property_value){0};
if (!edev)
return -EINVAL;
/* Check whether the property is supported or not */
if (!is_extcon_property_supported(id, prop))
return -EINVAL;
/* Find the cable index of external connector by using id */
index = find_cable_index_by_id(edev, id);
if (index < 0)
return index;
spin_lock_irqsave(&edev->lock, flags);
/* Check whether the property is available or not. */
if (!is_extcon_property_capability(edev, id, index, prop)) {
spin_unlock_irqrestore(&edev->lock, flags);
return -EPERM;
}
/*
* Check whether the external connector is attached.
* If external connector is detached, the user can not
* get the property value.
*/
if (!is_extcon_attached(edev, index)) {
spin_unlock_irqrestore(&edev->lock, flags);
return 0;
}
cable = &edev->cables[index];
/* Get the property value according to extcon type */
switch (prop) {
case EXTCON_PROP_USB_MIN ... EXTCON_PROP_USB_MAX:
*prop_val = cable->usb_propval[prop - EXTCON_PROP_USB_MIN];
break;
case EXTCON_PROP_CHG_MIN ... EXTCON_PROP_CHG_MAX:
*prop_val = cable->chg_propval[prop - EXTCON_PROP_CHG_MIN];
break;
case EXTCON_PROP_JACK_MIN ... EXTCON_PROP_JACK_MAX:
*prop_val = cable->jack_propval[prop - EXTCON_PROP_JACK_MIN];
break;
case EXTCON_PROP_DISP_MIN ... EXTCON_PROP_DISP_MAX:
*prop_val = cable->disp_propval[prop - EXTCON_PROP_DISP_MIN];
break;
default:
ret = -EINVAL;
break;
}
spin_unlock_irqrestore(&edev->lock, flags);
return ret;
}
EXPORT_SYMBOL_GPL(extcon_get_property);
/**
* extcon_set_property() - Set the property value of an external connector.
* @edev: the extcon device
* @id: the unique id indicating an external connector
* @prop: the property id indicating an extcon property
* @prop_val: the pointer including the new value of extcon property
*
* Note that each property should be included in the list of supported
* properties according to the extcon type.
*
* Returns 0 if success or error number if fail.
*/
int extcon_set_property(struct extcon_dev *edev, unsigned int id,
unsigned int prop,
union extcon_property_value prop_val)
{
struct extcon_cable *cable;
unsigned long flags;
int index, ret = 0;
if (!edev)
return -EINVAL;
/* Check whether the property is supported or not */
if (!is_extcon_property_supported(id, prop))
return -EINVAL;
/* Find the cable index of external connector by using id */
index = find_cable_index_by_id(edev, id);
if (index < 0)
return index;
spin_lock_irqsave(&edev->lock, flags);
/* Check whether the property is available or not. */
if (!is_extcon_property_capability(edev, id, index, prop)) {
spin_unlock_irqrestore(&edev->lock, flags);
return -EPERM;
}
cable = &edev->cables[index];
/* Set the property value according to extcon type */
switch (prop) {
case EXTCON_PROP_USB_MIN ... EXTCON_PROP_USB_MAX:
cable->usb_propval[prop - EXTCON_PROP_USB_MIN] = prop_val;
break;
case EXTCON_PROP_CHG_MIN ... EXTCON_PROP_CHG_MAX:
cable->chg_propval[prop - EXTCON_PROP_CHG_MIN] = prop_val;
break;
case EXTCON_PROP_JACK_MIN ... EXTCON_PROP_JACK_MAX:
cable->jack_propval[prop - EXTCON_PROP_JACK_MIN] = prop_val;
break;
case EXTCON_PROP_DISP_MIN ... EXTCON_PROP_DISP_MAX:
cable->disp_propval[prop - EXTCON_PROP_DISP_MIN] = prop_val;
break;
default:
ret = -EINVAL;
break;
}
spin_unlock_irqrestore(&edev->lock, flags);
return ret;
}
EXPORT_SYMBOL_GPL(extcon_set_property);
/**
* extcon_set_property_sync() - Set property of an external connector with sync.
* @prop_val: the pointer including the new value of extcon property
*
* Note that when setting the property value of external connector,
* the external connector should be attached. The each property should
* be included in the list of supported properties according to extcon type.
*
* Returns 0 if success or error number if fail.
*/
int extcon_set_property_sync(struct extcon_dev *edev, unsigned int id,
unsigned int prop,
union extcon_property_value prop_val)
{
int ret;
ret = extcon_set_property(edev, id, prop, prop_val);
if (ret < 0)
return ret;
return extcon_sync(edev, id);
}
EXPORT_SYMBOL_GPL(extcon_set_property_sync);
/**
* extcon_get_property_capability() - Get the capability of the property
* for an external connector.
* @edev: the extcon device
* @id: the unique id indicating an external connector
* @prop: the property id indicating an extcon property
*
* Returns 1 if the property is available or 0 if not available.
*/
int extcon_get_property_capability(struct extcon_dev *edev, unsigned int id,
unsigned int prop)
{
int index;
if (!edev)
return -EINVAL;
/* Check whether the property is supported or not */
if (!is_extcon_property_supported(id, prop))
return -EINVAL;
/* Find the cable index of external connector by using id */
index = find_cable_index_by_id(edev, id);
if (index < 0)
return index;
return is_extcon_property_capability(edev, id, index, prop);
}
EXPORT_SYMBOL_GPL(extcon_get_property_capability);
/**
* extcon_set_property_capability() - Set the capability of the property
* for an external connector.
* @edev: the extcon device
* @id: the unique id indicating an external connector
* @prop: the property id indicating an extcon property
*
* Note that this function set the capability of the property
* for an external connector in order to mark the bit in capability
* bitmap which mean the available state of the property.
*
* Returns 0 if success or error number if fail.
*/
int extcon_set_property_capability(struct extcon_dev *edev, unsigned int id,
unsigned int prop)
{
struct extcon_cable *cable;
int index, type, ret = 0;
if (!edev)
return -EINVAL;
/* Check whether the property is supported or not. */
if (!is_extcon_property_supported(id, prop))
return -EINVAL;
/* Find the cable index of external connector by using id. */
index = find_cable_index_by_id(edev, id);
if (index < 0)
return index;
type = get_extcon_type(prop);
if (type < 0)
return type;
cable = &edev->cables[index];
switch (type) {
case EXTCON_TYPE_USB:
__set_bit(prop - EXTCON_PROP_USB_MIN, cable->usb_bits);
break;
case EXTCON_TYPE_CHG:
__set_bit(prop - EXTCON_PROP_CHG_MIN, cable->chg_bits);
break;
case EXTCON_TYPE_JACK:
__set_bit(prop - EXTCON_PROP_JACK_MIN, cable->jack_bits);
break;
case EXTCON_TYPE_DISP:
__set_bit(prop - EXTCON_PROP_DISP_MIN, cable->disp_bits);
break;
default:
ret = -EINVAL;
}
return ret;
}
EXPORT_SYMBOL_GPL(extcon_set_property_capability);
/**
* extcon_get_extcon_dev() - Get the extcon device instance from the name.
* @extcon_name: the extcon name provided with extcon_dev_register()
*
* Return the pointer of extcon device if success or ERR_PTR(err) if fail.
*/
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 notifier block to get notified by
* any state changes from the extcon.
* @edev: the extcon device
* @id: the unique id indicating an external connector
* @nb: a notifier block to be registered
*
* Note that the second parameter given to the callback of nb (val) is
* the current state of an external connector and the third pameter
* is the pointer of extcon device.
*
* Returns 0 if success or error number if fail.
*/
int extcon_register_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_register(&edev->nh[idx], nb);
spin_unlock_irqrestore(&edev->lock, flags);
return ret;
}
EXPORT_SYMBOL_GPL(extcon_register_notifier);
/**
* extcon_unregister_notifier() - Unregister a notifier block from the extcon.
* @edev: the extcon device
* @id: the unique id indicating an external connector
* @nb: a notifier block to be registered
*
* Returns 0 if success or error number if fail.
*/
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);
/**
* extcon_register_notifier_all() - Register a notifier block for all connectors.
* @edev: the extcon device
* @nb: a notifier block to be registered
*
* Note that this function registers a notifier block in order to receive
* the state change of all supported external connectors from extcon device.
* And the second parameter given to the callback of nb (val) is
* the current state and the third pameter is the pointer of extcon device.
*
* Returns 0 if success or error number if fail.
*/
int extcon_register_notifier_all(struct extcon_dev *edev,
struct notifier_block *nb)
{
unsigned long flags;
int ret;
if (!edev || !nb)
return -EINVAL;
spin_lock_irqsave(&edev->lock, flags);
ret = raw_notifier_chain_register(&edev->nh_all, nb);
spin_unlock_irqrestore(&edev->lock, flags);
return ret;
}
EXPORT_SYMBOL_GPL(extcon_register_notifier_all);
/**
* extcon_unregister_notifier_all() - Unregister a notifier block from extcon.
* @edev: the extcon device
* @nb: a notifier block to be registered
*
* Returns 0 if success or error number if fail.
*/
int extcon_unregister_notifier_all(struct extcon_dev *edev,
struct notifier_block *nb)
{
unsigned long flags;
int ret;
if (!edev || !nb)
return -EINVAL;
spin_lock_irqsave(&edev->lock, flags);
ret = raw_notifier_chain_unregister(&edev->nh_all, nb);
spin_unlock_irqrestore(&edev->lock, flags);
return ret;
}
EXPORT_SYMBOL_GPL(extcon_unregister_notifier_all);
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;
}
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: the array of the supported external connectors
* ending with EXTCON_NONE.
*
* Note that this function allocates the memory for extcon device
* and initialize default setting for the extcon device.
*
* Returns the pointer memory of allocated extcon_dev if success
* or ERR_PTR(err) if fail.
*/
struct extcon_dev *extcon_dev_allocate(const unsigned int *supported_cable)
{
struct extcon_dev *edev;
if (!supported_cable)
return ERR_PTR(-EINVAL);
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
*/
void extcon_dev_free(struct extcon_dev *edev)
{
kfree(edev);
}
EXPORT_SYMBOL_GPL(extcon_dev_free);
/**
* extcon_dev_register() - Register an new extcon device
* @edev: the extcon device to be registered
*
* Among the members of edev struct, please set the "user initializing data"
* do not set the values of "internal data", which are initialized by
* this function.
*
* Note that before calling this funciton, have to allocate the memory
* of an extcon device by using the extcon_dev_allocate(). And the extcon
* dev should include the supported_cable information.
*
* Returns 0 if success or error number if fail.
*/
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 || !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 *str;
struct extcon_cable *cable;
edev->cables = kcalloc(edev->max_supported,
sizeof(struct extcon_cable),
GFP_KERNEL);
if (!edev->cables) {
ret = -ENOMEM;
goto err_sysfs_alloc;
}
for (index = 0; index < edev->max_supported; index++) {
cable = &edev->cables[index];
str = kasprintf(GFP_KERNEL, "cable.%d", index);
if (!str) {
for (index--; index >= 0; index--) {
cable = &edev->cables[index];
kfree(cable->attr_g.name);
}
ret = -ENOMEM;
goto err_alloc_cables;
}
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 *name;
/* Count the size of mutually_exclusive array */
for (index = 0; edev->mutually_exclusive[index]; index++)
;
edev->attrs_muex = kcalloc(index + 1,
sizeof(struct attribute *),
GFP_KERNEL);
if (!edev->attrs_muex) {
ret = -ENOMEM;
goto err_muex;
}
edev->d_attrs_muex = kcalloc(index,
sizeof(struct device_attribute),
GFP_KERNEL);
if (!edev->d_attrs_muex) {
ret = -ENOMEM;
kfree(edev->attrs_muex);
goto err_muex;
}
for (index = 0; edev->mutually_exclusive[index]; index++) {
name = kasprintf(GFP_KERNEL, "0x%x",
edev->mutually_exclusive[index]);
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;
}
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 =
kcalloc(edev->max_supported + 2,
sizeof(struct attribute_group *),
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;
}
spin_lock_init(&edev->lock);
edev->nh = devm_kcalloc(&edev->dev, edev->max_supported,
sizeof(*edev->nh), 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]);
RAW_INIT_NOTIFIER_HEAD(&edev->nh_all);
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 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;
if (!edev)
return;
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);
}
put_device(&edev->dev);
}
EXPORT_SYMBOL_GPL(extcon_dev_unregister);
#ifdef CONFIG_OF
/*
* extcon_find_edev_by_node - Find the extcon device from devicetree.
* @node : OF node identifying edev
*
* Return the pointer of extcon device if success or ERR_PTR(err) if fail.
*/
struct extcon_dev *extcon_find_edev_by_node(struct device_node *node)
{
struct extcon_dev *edev;
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)
goto out;
edev = ERR_PTR(-EPROBE_DEFER);
out:
mutex_unlock(&extcon_dev_list_lock);
return edev;
}
/*
* extcon_get_edev_by_phandle - Get the extcon device from devicetree.
* @dev : the instance to the given device
* @index : the index into list of extcon_dev
*
* Return the pointer of extcon device if success or ERR_PTR(err) if fail.
*/
struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev, int index)
{
struct device_node *node;
struct extcon_dev *edev;
if (!dev)
return ERR_PTR(-EINVAL);
if (!dev->of_node) {
dev_dbg(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_dbg(dev, "failed to get phandle in %pOF node\n",
dev->of_node);
return ERR_PTR(-ENODEV);
}
edev = extcon_find_edev_by_node(node);
of_node_put(node);
return edev;
}
#else
struct extcon_dev *extcon_find_edev_by_node(struct device_node *node)
{
return ERR_PTR(-ENOSYS);
}
struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev, int index)
{
return ERR_PTR(-ENOSYS);
}
#endif /* CONFIG_OF */
EXPORT_SYMBOL_GPL(extcon_find_edev_by_node);
EXPORT_SYMBOL_GPL(extcon_get_edev_by_phandle);
/**
* extcon_get_edev_name() - Get the name of the extcon device.
* @edev: the extcon device
*/
const char *extcon_get_edev_name(struct extcon_dev *edev)
{
return !edev ? NULL : edev->name;
}
EXPORT_SYMBOL_GPL(extcon_get_edev_name);
static int __init extcon_class_init(void)
{
return create_extcon_class();
}
module_init(extcon_class_init);
static void __exit extcon_class_exit(void)
{
class_destroy(extcon_class);
}
module_exit(extcon_class_exit);
MODULE_AUTHOR("Chanwoo Choi <cw00.choi@samsung.com>");
MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
MODULE_DESCRIPTION("External Connector (extcon) framework");
MODULE_LICENSE("GPL v2");
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