kernel-fxtec-pro1x/drivers/extcon/extcon.c
Chanwoo Choi 8a9dbb779f extcon: Release locking when sending the notification of connector state
Previously, extcon used the spinlock before calling the notifier_call_chain
to prevent the scheduled out of task and to prevent the notification delay.
When spinlock is locked for sending the notification, deadlock issue
occured on the side of extcon consumer device. To fix this issue,
extcon consumer device should always use the work. it is always not
reasonable to use work.

To fix this issue on extcon consumer device, release locking when sending
the notification of connector state.

Fixes: ab11af049f ("extcon: Add the synchronization extcon APIs to support the notification")
Cc: stable@vger.kernel.org
Cc: Roger Quadros <rogerq@ti.com>
Cc: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2018-07-12 09:06:31 +09:00

1440 lines
36 KiB
C

/*
* 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>
*
* 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/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 = -EINVAL;
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 buf[10];
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];
snprintf(buf, 10, "cable.%d", index);
str = kzalloc(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 = 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++) {
sprintf(buf, "0x%x", edev->mutually_exclusive[index]);
name = kzalloc(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 =
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;
}
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");