linux/Documentation/ABI/testing/sysfs-class-extcon

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Extcon (external connector): import Android's switch class and modify. 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: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Reviewed-by: Mark 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 - Removed out-of-date Kconfig entry Changes from v6 - Updated comment/strings - Revised "Android-compatible" mode.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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-20 13:16:22 +08:00
What: /sys/class/extcon/.../
Extcon: support multiple states at a device. 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: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Kyungmin 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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-20 13:16:25 +08:00
Date: February 2012
Extcon (external connector): import Android's switch class and modify. 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: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Reviewed-by: Mark 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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-20 13:16:22 +08:00
Contact: MyungJoo Ham <myungjoo.ham@samsung.com>
Description:
Provide a place in sysfs for the extcon objects.
This allows accessing extcon specific variables.
The name of extcon object denoted as ... is the name given
with extcon_dev_register.
Extcon: support multiple states at a device. 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: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Kyungmin 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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-20 13:16:25 +08:00
One extcon device denotes a single external connector
port. An external connector may have multiple cables
attached simultaneously. Many of docks, cradles, and
accessory cables have such capability. For example,
the 30-pin port of Nuri board (/arch/arm/mach-exynos)
may have both HDMI and Charger attached, or analog audio,
video, and USB cables attached simulteneously.
Extcon (external connector): import Android's switch class and modify. 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: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Reviewed-by: Mark 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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-20 13:16:22 +08:00
What: /sys/class/extcon/.../name
Extcon: support multiple states at a device. 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: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Kyungmin 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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-20 13:16:25 +08:00
Date: February 2012
Extcon (external connector): import Android's switch class and modify. 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: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Reviewed-by: Mark 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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-20 13:16:22 +08:00
Contact: MyungJoo Ham <myungjoo.ham@samsung.com>
Description:
The /sys/class/extcon/.../name shows the name of the extcon
object. If the extcon object has an optional callback
"show_name" defined, the callback will provide the name with
this sysfs node.
What: /sys/class/extcon/.../state
Extcon: support multiple states at a device. 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: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Kyungmin 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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-20 13:16:25 +08:00
Date: February 2012
Contact: MyungJoo Ham <myungjoo.ham@samsung.com>
Description:
The /sys/class/extcon/.../state shows and stores the cable
attach/detach information of the corresponding extcon object.
If the extcon object has an optional callback "show_state"
defined, the showing function is overriden with the optional
callback.
If the default callback for showing function is used, the
format is like this:
# cat state
USB_OTG=1
HDMI=0
TA=1
EAR_JACK=0
#
In this example, the extcon device have USB_OTG and TA
cables attached and HDMI and EAR_JACK cables detached.
In order to update the state of an extcon device, enter a hex
state number starting with 0x.
echo 0xHEX > state
This updates the whole state of the extcon dev.
Inputs of all the methods are required to meet the
mutually_exclusive contidions if they exist.
It is recommended to use this "global" state interface if
you need to enter the value atomically. The later state
interface associated with each cable cannot update
multiple cable states of an extcon device simultaneously.
What: /sys/class/extcon/.../cable.x/name
Date: February 2012
Contact: MyungJoo Ham <myungjoo.ham@samsung.com>
Description:
The /sys/class/extcon/.../cable.x/name shows the name of cable
"x" (integer between 0 and 31) of an extcon device.
What: /sys/class/extcon/.../cable.x/state
Date: February 2012
Extcon (external connector): import Android's switch class and modify. 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: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Reviewed-by: Mark 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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-20 13:16:22 +08:00
Contact: MyungJoo Ham <myungjoo.ham@samsung.com>
Description:
Extcon: support multiple states at a device. 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: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Kyungmin 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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-20 13:16:25 +08:00
The /sys/class/extcon/.../cable.x/name shows and stores the
state of cable "x" (integer between 0 and 31) of an extcon
device. The state value is either 0 (detached) or 1
(attached).