EXTCON_PROP_USB_SS (SuperSpeed)[1] is necessary to distinguish
between USB/USB2 and USB3 connections on USB Type-C cables.

[1] https://en.wikipedia.org/wiki/USB#Overview

Cc: Chris Zhong <zyw@rock-chips.com>
Signed-off-by: NGuenter Roeck <groeck@chromium.org>
Signed-off-by: NChanwoo Choi <cw00.choi@samsung.com>

This patchs add the new EXTCON_CHG_WPT for Wireless Power Transfer[1].
The Wireless Power Transfer is the transmission of electronical energy
from a power source. The EXTCON_CHG_WPT has the EXTCON_TYPE_CHG.

[1] https://en.wikipedia.org/wiki/Wireless_power_transferSigned-off-by: NChanwoo Choi <cw00.choi@samsung.com>

This patch adds the new EXTCON_DISP_HMD id for Head-mounted Display[1] device.
The HMD device is usually for USB connector type So, the HMD connector
has the two extcon types of both EXTCON_TYPE_DISP and EXTCON_TYPE_USB.

[1] https://en.wikipedia.org/wiki/Head-mounted_displaySigned-off-by: NChanwoo Choi <cw00.choi@samsung.com>

Add EXTCON_DISP_DP for the Display external connector. For Type-C
connector the DisplayPort can work as an Alternate Mode(VESA DisplayPort
Alt Mode on USB Type-C Standard). The Type-C support both normal
and flipped orientation, so add a property to extcon.
Signed-off-by: NChris Zhong <zyw@rock-chips.com>
Signed-off-by: NChanwoo Choi <cw00.choi@samsung.com>
Tested-by: NChris Zhong <zyw@rock-chips.com>
Tested-by: NGuenter Roeck <groeck@chromium.org>
Reviewed-by: NGuenter Roeck <groeck@chromium.org>

This patch adds the synchronization extcon APIs to support the notifications
for both state and property. When extcon_*_sync() functions is called,
the extcon informs the information from extcon provider to extcon client.

The extcon driver may need to change the both state and multiple properties
at the same time. After setting the data of a external connector,
the extcon send the notification to client driver with the extcon_*_sync().

The list of new extcon APIs as following:
- extcon_sync() : Send the notification for each external connector to
		synchronize the information between extcon provider driver
		and extcon client driver.
- extcon_set_state_sync() : Set the state of external connector with noti.
- extcon_set_property_sync() : Set the property of external connector with noti.

For example,
case 1, change the state of external connector and synchronized the data.
	extcon_set_state_sync(edev, EXTCON_USB, 1);

case 2, change both the state and property of external connector
	and synchronized the data.
	extcon_set_state(edev, EXTCON_USB, 1);
	extcon_set_property(edev, EXTCON_USB, EXTCON_PROP_USB_VBUS 1);
	extcon_sync(edev, EXTCON_USB);

case 3, change the property of external connector and synchronized the data.
	extcon_set_property(edev, EXTCON_USB, EXTCON_PROP_USB_VBUS, 0);
	extcon_sync(edev, EXTCON_USB);

case 4, change the property of external connector and synchronized the data.
	extcon_set_property_sync(edev, EXTCON_USB, EXTCON_PROP_USB_VBUS, 0);
Signed-off-by: NChanwoo Choi <cw00.choi@samsung.com>
Tested-by: NChris Zhong <zyw@rock-chips.com>
Tested-by: NGuenter Roeck <groeck@chromium.org>
Reviewed-by: NGuenter Roeck <groeck@chromium.org>

This patch just renames the existing extcon_get/set_cable_state_()
as following because of maintaining the function naming pattern
like as extcon APIs for property.
- extcon_set_cable_state_() -> extcon_set_state()
- extcon_get_cable_state_() -> extcon_get_state()

But, this patch remains the old extcon_set/get_cable_state_() functions
to prevent the build break. After altering new APIs, remove the old APIs.
Signed-off-by: NChanwoo Choi <cw00.choi@samsung.com>
Tested-by: NChris Zhong <zyw@rock-chips.com>
Tested-by: NGuenter Roeck <groeck@chromium.org>
Reviewed-by: NGuenter Roeck <groeck@chromium.org>

This patch adds the support of the property capability setting. This function
decides the supported properties of each external connector on extcon provider
driver.

Ths list of new extcon APIs to get/set the capability of property as following:
- int extcon_get_property_capability(struct extcon_dev *edev,
					unsigned int id, unsigned int prop);
- int extcon_set_property_capability(struct extcon_dev *edev,
					unsigned int id, unsigned int prop);
Signed-off-by: NChanwoo Choi <cw00.choi@samsung.com>
Tested-by: NChris Zhong <zyw@rock-chips.com>
Tested-by: NGuenter Roeck <groeck@chromium.org>
Reviewed-by: NGuenter Roeck <groeck@chromium.org>

This patch support the extcon property for the external connector
because each external connector might have the property according to
the H/W design and the specific characteristics.

- EXTCON_PROP_USB_[property name]
- EXTCON_PROP_CHG_[property name]
- EXTCON_PROP_JACK_[property name]
- EXTCON_PROP_DISP_[property name]

Add the new extcon APIs to get/set the property value as following:
- int extcon_get_property(struct extcon_dev *edev, unsigned int id,
			unsigned int prop,
			union extcon_property_value *prop_val)
- int extcon_set_property(struct extcon_dev *edev, unsigned int id,
			unsigned int prop,
			union extcon_property_value prop_val)
Signed-off-by: NChanwoo Choi <cw00.choi@samsung.com>
Tested-by: NChris Zhong <zyw@rock-chips.com>
Tested-by: NGuenter Roeck <groeck@chromium.org>
Reviewed-by: NGuenter Roeck <groeck@chromium.org>

This patch adds the new extcon type to group the each connecotr
into following five category. This type would be used to handle
the connectors as a group unit instead of a connector unit.
- EXTCON_TYPE_USB  : USB connector
- EXTCON_TYPE_CHG  : Charger connector
- EXTCON_TYPE_JACK : Jack connector
- EXTCON_TYPE_DISP : Display connector
- EXTCON_TYPE_MISC : Miscellaneous connector

Also, each external connector is possible to belong to one more extcon type.
In caes of EXTCON_CHG_USB_SDP, it have the EXTCON_TYPE_CHG and EXTCON_TYPE_USB.
Signed-off-by: NChanwoo Choi <cw00.choi@samsung.com>
Tested-by: NChris Zhong <zyw@rock-chips.com>
Tested-by: NGuenter Roeck <groeck@chromium.org>
Signed-off-by: NMyungJoo Ham <myungjoo.ham@samsung.com>
Reviewed-by: NGuenter Roeck <groeck@chromium.org>

This patch restrict the usage of extcon_update_state() in the extcon
core because the extcon_update_state() use the bit masking to change
the state of external connector. When this function is used in device drivers,
it may occur the probelm with the handling mistake of bit masking.

Also, this patch removes the extcon_get/set_state() functions because these
functions use the bit masking which is reluctant way. Instead, extcon
provides the extcon_set/get_cable_state_() functions.
Signed-off-by: NChanwoo Choi <cw00.choi@samsung.com>

This patch fixes the wrong description about extcon_set/get_cable_state_()
because they use the unique id of external connector instead of legacy name.
Signed-off-by: NChanwoo Choi <cw00.choi@samsung.com>

This patch adds the resource-managed functions for register/unregister
the extcon notifier with the id of each external connector. This function
will make it easy to handle the extcon notifier.

- int devm_extcon_register_notifier(struct device *dev,
				struct extcon_dev *edev, unsigned int id,
				struct notifier_block *nb);
- void devm_extcon_unregister_notifier(struct device *dev,
				struct extcon_dev *edev, unsigned int id,
				struct notifier_block *nb);
Signed-off-by: NChanwoo Choi <cw00.choi@samsung.com>

This patch moves the struct extcon_cable because that should
be only handled by extcon core. There are no reason to publish
the internal structure.
Signed-off-by: NChanwoo Choi <cw00.choi@samsung.com>

This patch removes the deprecated extcon functions using string type
to identify the type of external connector. The Commit 2a9de9c0
("extcon: Use the unique id for external connector instead of string)
uses the unique id to separate the type of external connector instead of
string name.
- extcon_register_interest()
- extcon_unregister_interest()
- extcon_set_cable_state()
- extcon_get_cable_state()

And, extcon_register_interest() finds the first extcon device to include the
requested external connector from extcon client device and then register the
notifier if extcon device argument is NULL. Instead, extcon_register_notifier()
supports this feature.

But, this patch remains the deprecatd function definition to prevent
the build break.
Signed-off-by: NChanwoo Choi <cw00.choi@samsung.com>

This patch modifies the id and name of external connector with the
additional prefix to clarify both attribute and meaning of external
connector as following:
- EXTCON_CHG_* mean the charger connector.
- EXTCON_JACK_* mean the jack connector.
- EXTCON_DISP_* mean the display port connector.

Following table show the new name of external connector with old name:
--------------------------------------------------
Old extcon name         | New extcon name        |
--------------------------------------------------
EXTCON_TA               | EXTCON_CHG_USB_DCP     |
EXTCON_CHARGE_DOWNSTREAM| EXTCON_CHG_USB_CDP     |
EXTCON_FAST_CHARGER     | EXTCON_CHG_USB_FAST    |
EXTCON_SLOW_CHARGER     | EXTCON_CHG_USB_SLOW    |
--------------------------------------------------
EXTCON_MICROPHONE       | EXTCON_JACK_MICROPHONE |
EXTCON_HEADPHONE        | EXTCON_JACK_HEADPHONE  |
EXTCON_LINE_IN          | EXTCON_JACK_LINE_IN    |
EXTCON_LINE_OUT         | EXTCON_JACK_LINE_OUT   |
EXTCON_VIDEO_IN         | EXTCON_JACK_VIDEO_IN   |
EXTCON_VIDEO_OUT        | EXTCON_JACK_VIDEO_OUT  |
EXTCON_SPDIF_IN         | EXTCON_JACK_SPDIF_IN   |
EXTCON_SPDIF_OUT        | EXTCON_JACK_SPDIF_OUT  |
--------------------------------------------------
EXTCON_HMDI             | EXTCON_DISP_HDMI       |
EXTCON_MHL              | EXTCON_DISP_MHL        |
EXTCON_DVI              | EXTCON_DISP_DVI        |
EXTCON_VGA              | EXTCON_DISP_VGA        |
--------------------------------------------------

And, when altering the name of USB charger connector, EXTCON refers to the
"Battery Charging v1.2 Spec and Adopters Agreement"[1] to use the standard
name of USB charging port as following. Following name of USB charging port
are already used in power_supply subsystem. We chan check it on patch[2].
- EXTCON_CHG_USB_SDP	/* Standard Downstream Port */
- EXTCON_CHG_USB_DCP	/* Dedicated Charging Port */
- EXTCON_CHG_USB_CDP	/* Charging Downstream Port */
- EXTCON_CHG_USB_ACA	/* Accessory Charger Adapter */

[1] www.usb.org/developers/docs/devclass_docs/BCv1.2_070312.zip
[2] commit 85efc8a1 ("power_supply: Add types for USB chargers")
Signed-off-by: NChanwoo Choi <cw00.choi@samsung.com>
[ckeepax: For the Arizona changes]
Acked-by: NCharles Keepax <ckeepax@opensource.wolfsonmicro.com>
Reviewed-by: NRoger Quadros <rogerq@ti.com>

This patch removes the optional print_state() function pointer which included
in 'struct extcon_dev' because the extcon must maintain the consistent name
of extcon device on sysfs instead of inconsistent state of external connectors.
Signed-off-by: NChanwoo Choi <cw00.choi@samsung.com>

This patch removes the duplicate header file in extcon.h.
Signed-off-by: NChanwoo Choi <cw00.choi@samsung.com>

This patch just redefine the unique id of supported external connectors without
'enum extcon' type. Because unique id would be used on devictree file(*.dts) to
indicate the specific external connectors like key number of input framework.
So, I have the plan to move this definitions to following header file which
includes the unique id of supported external connectors.
- include/dt-bindings/extcon/extcon.h

Fixes: 2a9de9c0 ("extcon: Use the unique id for external connector instead of string")
Signed-off-by: NChanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch removes the optional print_name() function pointer included in
'struct extcon_dev' because the extcon must maintain the consistent name of
extcon device on sysfs instead of inconsistent name. After merged patch[1],
extcon can maintain the consistent name of extcon device without any hard-coded
device name.
[1] https://lkml.org/lkml/2015/4/27/258Signed-off-by: NChanwoo Choi <cw00.choi@samsung.com>

Previously, extcon consumer driver used the extcon_register_interest()
to register the notifier chain and then to receive the notifier event
when external connector's state is changed. When registering the notifier chain
for specific external connector with extcon_register_interest(), it used the
the string name of external connector directly. There are potential problem
because of unclear, non-standard and inconsequent cable name. Namely,
it is not appropriate method to identify each external connector.

So, this patch modify the prototype of extcon_register_notifier() by using
the 'enum extcon' which are the unique id for each external connector
instead of unclear string method.

- Previously, the extcon consumer driver used the extcon_register_interest()
with 'cable_name' to point out the specific external connector. Also. it used
the un-needed structure (struct extcon_specific_cable_nb).
: int extcon_register_interest(struct extcon_specific_cable_nb *obj,
			     const char *extcon_name, const char *cable_name,
			     struct notifier_block *nb)

- Newly, the updated extcon_register_notifier() would definitely support
the same feature to detech the changed state of external connector without
any specific structure (struct extcon_specific_cable_nb).
: int extcon_register_notifier(struct extcon_dev *edev, enum extcon id,
			     struct notifier_block *nb)

This patch support the both extcon_register_interest() and new extcon_register_
notifier(). But the extcon_{register|unregister}_interest() will be deprecated
because extcon core would support the notifier event for extcon consumer driver
with only updated extcon_register_notifier() and 'extcon_specific_cable_nb'
will be removed if there are no extcon consumer driver with legacy
extcon_{register|unregister}_interest().
Signed-off-by: NChanwoo Choi <cw00.choi@samsung.com>
Reviewed-by: NKrzysztof Kozlowski <k.kozlowski@samsung.com>

This patch uses the unique id to identify the type of external connector instead
of string name. The string name have the many potential issues. So, this patch
defines the 'extcon' enumeration which includes all supported external connector
on EXTCON subsystem. If new external connector is necessary, the unique id of
new connector have to be added in 'extcon' enumeration. There are current
supported external connector in 'enum extcon' as following:

enum extcon {
	EXTCON_NONE		= 0x0,

	/* USB external connector */
	EXTCON_USB		= 0x1,
	EXTCON_USB_HOST		= 0x2,

	/* Charger external connector */
	EXTCON_TA		= 0x10,
	EXTCON_FAST_CHARGER	= 0x11,
	EXTCON_SLOW_CHARGER	= 0x12,
	EXTCON_CHARGE_DOWNSTREAM = 0x13,

	/* Audio and video external connector */
	EXTCON_LINE_IN		= 0x20,
	EXTCON_LINE_OUT		= 0x21,
	EXTCON_MICROPHONE	= 0x22,
	EXTCON_HEADPHONE	= 0x23,

	EXTCON_HDMI		= 0x30,
	EXTCON_MHL		= 0x31,
	EXTCON_DVI		= 0x32,
	EXTCON_VGA		= 0x33,
	EXTCON_SPDIF_IN		= 0x34,
	EXTCON_SPDIF_OUT	= 0x35,
	EXTCON_VIDEO_IN		= 0x36,
	EXTCON_VIDEO_OUT	= 0x37,

	/* Miscellaneous external connector */
	EXTCON_DOCK		= 0x50,
	EXTCON_JIG		= 0x51,
	EXTCON_MECHANICAL	= 0x52,

	EXTCON_END,
};

For example in extcon-arizona.c:
To use unique id removes the potential issue about handling
the inconsistent name of external connector with string.
- Previously, use the string to register the type of arizona jack connector
static const char *arizona_cable[] = {
	"Mechanical",
	"Microphone",
	"Headphone",
	"Line-out",
};
- Newly, use the unique id to register the type of arizona jack connector
static const enum extcon arizona_cable[] = {
	EXTCON_MECHANICAL,
	EXTCON_MICROPHONE,
	EXTCON_HEADPHONE,
	EXTCON_LINE_OUT,

	EXTCON_NONE,
};

And this patch modify the prototype of extcon_{get|set}_cable_state_() which
uses the 'enum extcon id' instead of 'cable_index'. Because although one more
extcon drivers support USB cable, each extcon driver might has the differnt
'cable_index' for USB cable. All extcon drivers can use the unique id number
for same external connector with modified extcon_{get|set}_cable_state_().

- Previously, use 'cable_index' on these functions:
extcon_get_cable_state_(struct extcon_dev*, int cable_index)
extcon_set_cable_state_(struct extcon_dev*, int cable_index, bool state)

-Newly, use 'enum extcon id' on these functions:
extcon_get_cable_state_(struct extcon_dev*, enum extcon id)
extcon_set_cable_state_(struct extcon_dev*, enum extcon id, bool state)

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Felipe Balbi <balbi@ti.com>
Signed-off-by: NChanwoo Choi <cw00.choi@samsung.com>
Acked-by: NRoger Quadros <rogerq@ti.com>
Acked-by: NCharles Keepax <ckeepax@opensource.wolfsonmicro.com>
Acked-by: NRamakrishna Pallala <ramakrishna.pallala@intel.com>
Reviewed-by: NKrzysztof Kozlowski <k.kozlowski@samsung.com>
[arnd: Report the build break about drivers/usb/phy/phy-tahvo.c after using the
unique id for external connector insteadf of string]
Reported-by: NArnd Bergmann <arnd@arndb.de>
[dan.carpenter: Report the build warning of extcon_{set|get}_cable_state_()]
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>

This patch clean up the extcon core driver by fixing the checkpatch warning
and minor coding style issue.
Signed-off-by: NChanwoo Choi <cw00.choi@samsung.com>

This patch adds the extcon_get_edev_name() API to get the name of extcon device
because all information inclued in the structure extcon_dev should be accessed
by extcon core API instead of directly accessing the data.
Signed-off-by: NChanwoo Choi <cw00.choi@samsung.com>

This patch add device managed devm_extcon_dev_{allocate,free} to automatically
free the memory of extcon_dev structure without handling free operation.
Signed-off-by: NChanwoo Choi <cw00.choi@samsung.com>
Reviewed-by: NFelipe Balbi <balbi@ti.com>

This patch add APIs to control the extcon device on extcon provider driver.
The extcon_dev_allocate() allocates the memory of extcon device and initializes
supported cables. And then extcon_dev_free() decrement the reference of the
device of extcon device and free the memory of the extcon device. This APIs
must need to implement devm_extcon_dev_allocate()/free() APIs.
Signed-off-by: NChanwoo Choi <cw00.choi@samsung.com>
Reviewed-by: NFelipe Balbi <balbi@ti.com>

Add resource-managed extcon device register function for convenience.
For example, if a extcon device is attached with new
devm_extcon_dev_register(), that extcon device is automatically
unregistered on driver detach.
Signed-off-by: NSangjung Woo <sangjung.woo@samsung.com>
[Fix bug about devm_extcon_dev_match/release() and code clean by Chanwoo Choi]
Signed-off-by: NChanwoo Choi <cw00.choi@samsung.com>

This patch move simply OF helper function to extcon core and change function
name as following:
- of_extcon_get_extcon_dev() -> extcon_get_edev_by_phandle()
Signed-off-by: NChanwoo Choi <cw00.choi@samsung.com>
Acked-by: NFelipe Balbi <balbi@ti.com>

This patch remove extcon_dev_register()'s second parameter which means
the pointer of parent device to simplify prototype of this function.
So, if extcon device has the parent device, it should set the pointer of
parent device to edev.dev.parent in extcon device driver instead of in
extcon_dev_register().

Cc: Graeme Gregory <gg@slimlogic.co.uk>
Cc: Kishon Vijay Abraham I <kishon@ti.com>
Cc: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Cc: Mark Brown <broonie@kernel.org>
Signed-off-by: NChanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: NMyungjoo Ham <myungjoo.ham@samsung.com>

The extcon device must always need 'struct device' so this patch change
field type of 'dev' instead of allocating memory for 'struct device' on
extcon_dev_register() function.
Signed-off-by: NChanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: NMyungjoo Ham <cw00.choi@samsung.com>

Signed-off-by: NChanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: NMyungjoo Ham <myungjoo.ham@samsung.com>

Corrected kernel_doc entries.
Signed-off-by: NMyungJoo Ham <myungjoo.ham@samsung.com>

This patch add missing header file(sysfs.h/device.h) to extcon.h
because 'struct extcon_dev' define attribute field(attr_g_muex/
attrs_muex/d_attrs_mues) and device_type field(extcon_dev_type).
Signed-off-by: NChanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: NMyungjoo Ham <myungjoo.ham@samsung.com>

With this change now individual drivers can use standard cable
names as below:
static const char *arizona_cable[] = {
    extcon_cable_name[EXTCON_USB],
    extcon_cable_name[EXTCON_USB_HOST],
    "CUSTOM_CABLE"
    NULL,
}
Signed-off-by: Nanish kumar <anish198519851985@gmail.com>
Signed-off-by: NMyungJoo Ham <myungjoo.ham@samsung.com>

Signed-off-by: NPeter Meerwald <pmeerw@pmeerw.net>
Signed-off-by: NMyungjoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Some accessory detection mechanisms are able to detect that something is
physically present in the socket separately to identifying what is present
in the socket. This information can be useful to applications, for example
allowing them to indicate that a potentially broken accessory is present,
so provide a standard way to report it to userspace.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

There could be cables that t recannot be attaches simulatenously. Extcon
device drivers may express such information via mutually_exclusive in
struct extcon_dev.

For example, for an extcon device with 16 cables (bits 0 to 15 are
available), if mutually_exclusive = { 0x7, 0xC0, 0x81, 0 }, then, the
following attachments are prohibitted.
{0, 1}
{0, 2}
{1, 2}
{6, 7}
{0, 7}
and every attachment set that are superset of one of the above.
For the detail, please refer to linux/include/linux/extcon.h.

The concept is suggested by NeilBrown <neilb@suse.de>
Signed-off-by: NMyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>

--
Changes from V5:
- Updated sysfs format
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

One switch device (e.g., MUIC(MAX8997, MAX77686, ...), and some 30-pin
devices) may have multiple cables attached. For example, one
30-pin port may inhabit a USB cable, an HDMI cable, and a mic.
Thus, one switch device requires multiple state bits each representing
a type of cable.

For such purpose, we use the 32bit state variable; thus, up to 32
different type of cables may be defined for a switch device. The list of
possible cables is defined by the array of cable names in the switch_dev
struct given to the class.
Signed-off-by: NChanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: NMyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>

--
Changes from V7
- Bugfixed in _call_per_cable() (incorrect nb) (Chanwoo Choi)
- Compiler error in header for !CONFIG_EXTCON (Chanwoo Choi)

Changes from V5
- Sysfs style reformed: subdirectory per cable.
- Updated standard cable names
- Removed unnecessary printf
- Bugfixes after testing

Changes from V4
- Bugfixes after more testing at Exynos4412 boards with userspace
  processses.

Changes from V3
- Bugfixes after more testing at Exynos4412 boards.

Changes from V2
- State can be stored by user
- Documentation updated

Changes from RFC
- Switch is renamed to extcon
- Added kerneldoc comments
- Added APIs to support "standard" cable names
- Added helper APIs to support notifier block registration with cable
  name.
- Regrouped function list in the header file.
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

State changes of extcon devices have been notified via kobjet_uevent.
This patch adds notifier interfaces in order to allow device drivers to
get notified easily. Along with notifier interface,
extcon_get_extcon_dev() function is added so that device drivers may
discover a extcon_dev easily.
Signed-off-by: NDonggeun Kim <dg77.kim@samsung.com>
Signed-off-by: NMyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

--
Changes from RFC
- Renamed switch to extcon
- Bugfix: extcon_dev_unregister()
- Bugfix: "edev->dev" is "internal" data.
- Added kerneldoc comments.
- Reworded comments.
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

External connector class (extcon) is based on and an extension of
Android kernel's switch class located at linux/drivers/switch/.

This patch provides the before-extension switch class moved to the
location where the extcon will be located (linux/drivers/extcon/) and
updates to handle class properly.

The before-extension class, switch class of Android kernel, commits
imported are:

switch: switch class and GPIO drivers. (splitted)
Author: Mike Lockwood <lockwood@android.com>

switch: Use device_create instead of device_create_drvdata.
Author: Arve Hjønnevåg <arve@android.com>

In this patch, upon the commits of Android kernel, we have added:
- Relocated and renamed for extcon.
- Comments, module name, and author information are updated
- Code clean for successing patches
- Bugfix: enabling write access without write functions
- Class/device/sysfs create/remove handling
- Added comments about uevents
- Format changes for extcon_dev_register() to have a parent dev.
Signed-off-by: NMyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

--
Changes from v7
- Compiler error fixed when it is compiled as a module.
- Removed out-of-date Kconfig entry

Changes from v6
- Updated comment/strings
- Revised "Android-compatible" mode.
   * Automatically activated if CONFIG_ANDROID && !CONFIG_ANDROID_SWITCH
   * Creates /sys/class/switch/*, which is a copy of /sys/class/extcon/*

Changes from v5
- Split the patch
- Style fixes
- "Android-compatible" mode is enabled by Kconfig option.

Changes from v2
- Updated name_show
- Sysfs entries are handled by class itself.
- Updated the method to add/remove devices for the class
- Comments on uevent send
- Able to become a module
- Compatible with Android platform

Changes from RFC
- Renamed to extcon (external connector) from multistate switch
- Added a seperated directory (drivers/extcon)
- Added kerneldoc comments
- Removed unused variables from extcon_gpio.c
- Added ABI Documentation.
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>