Rather than re-inventing the wheel we can use the hamming function
to calculate the number of bits set to check for violation of
exclusivity.
Signed-off-by: Nanish kumar <anish198519851985@gmail.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>

The operation of lockdep requires that all dynamically allocated sysfs
nodes are initialised using sysfs_attr_init() otherwise lots of warnings
are generated. Ensure that all the dynamically allocated attributes that
extcon generates have this done.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Replaced '_' with '-' in the extcon file names, which has been bogging
since new drivers have been using the standard naming.
Signed-off-by: NMyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

We can't create a link from the device to the compatibility switch class
since we already create a link from the device to to the extcon class
object and we try to use the same name for both links. This causes a loud
complaint from sysfs on boot.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

It's not referenced outside the core file.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.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>

This patch inform the state of only one cable instead of previous data
including the state of 32 cables to notifee which use
extcon_register_interest()
function to monitor whether the specific cable is attachd or detached.
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>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Return -ENOMEM if the kmalloc() fails.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Acked-by: NMyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Because extcon can also be a switch class for legacy userspace (Android)
and is a superset of switch class in drivers/staging/android/switch,
switch class may be removed.

- Remove switch class
- Remove switch class consideration in extcon class
Signed-off-by: NMyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.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>