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author | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-04-10 15:42:15 +0200 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-04-10 15:42:15 +0200 |
commit | 073a457d9ef46b34127f0bdcb879aaf8674819a5 (patch) | |
tree | d60939affb9de5cbab0068d2c7e89f3070e3f5e7 /Documentation | |
parent | 615cdd7cb475ede36642c5af65e8e32122445370 (diff) | |
parent | 70641a0a84e1ae3c6eee3d47ed5a482f85b11e3e (diff) | |
download | linux-073a457d9ef46b34127f0bdcb879aaf8674819a5.tar.gz linux-073a457d9ef46b34127f0bdcb879aaf8674819a5.tar.bz2 linux-073a457d9ef46b34127f0bdcb879aaf8674819a5.zip |
Merge tag 'extcon-next-for-4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/chanwoo/extcon into char-misc-next
Update extcon for 4.12
Detailed description for this pull request:
1. Add new 'extcon-intel-cht-wc.c' driver
- Intel Cherrytrail Whiskey Cove PMIC extcon driver supports
the detection of the charger connectors and the control.
2. Add new extcon API to monitor the all external connectors.
- The extcon consumer might need to monitor the all supported external
connectors from the extcon device. Before, the extcon consumer
should have each notifier_block structure for each external connector.
In order to support the requirement, the extcon adds new
extcon_register_notifier_all() API. The extcon consumer is able
to monitor the state change of all supported external connectors
from the extcon device by using only one notifier_block.
- extcon_(register|unregister)_notifier_all(struct extcon_dev *edev
struct notifier_block *nb)
- devm_extcon_(register|unregister)_notifier_all(struct device *dev,
struct extcon_dev *edev
struct notifier_block *nb)
3. Remove porting compatibility of old switch class
- The extcon removes the porting compatibility of old switch class
because there are no any use-case and requirement of switch class.
4. Update the extcon drivers and Fix the minor issues
- Revert the ACPI gpio interface on the extcon-usb-gpioc.c.
- Fix the issues related to the suspend-to-ram for both extcon-usb-gpio.c
and extcon-palmas.c.
- Add warning message for extcon-arizona.c when headphone detection is not
finished.
Diffstat (limited to 'Documentation')
-rw-r--r-- | Documentation/extcon/porting-android-switch-class | 123 |
1 files changed, 0 insertions, 123 deletions
diff --git a/Documentation/extcon/porting-android-switch-class b/Documentation/extcon/porting-android-switch-class deleted file mode 100644 index 49c81caef84d..000000000000 --- a/Documentation/extcon/porting-android-switch-class +++ /dev/null @@ -1,123 +0,0 @@ - - Staging/Android Switch Class Porting Guide - (linux/drivers/staging/android/switch) - (c) Copyright 2012 Samsung Electronics - -AUTHORS -MyungJoo Ham <myungjoo.ham@samsung.com> - -/***************************************************************** - * CHAPTER 1. * - * PORTING SWITCH CLASS DEVICE DRIVERS * - *****************************************************************/ - -****** STEP 1. Basic Functionality - No extcon extended feature, but switch features only. - -- struct switch_dev (fed to switch_dev_register/unregister) - @name: no change - @dev: no change - @index: drop (not used in switch device driver side anyway) - @state: no change - If you have used @state with magic numbers, keep it - at this step. - @print_name: no change but type change (switch_dev->extcon_dev) - @print_state: no change but type change (switch_dev->extcon_dev) - -- switch_dev_register(sdev, dev) - => extcon_dev_register(edev) - : type change (sdev->edev) - : remove second param('dev'). if edev has parent device, should store - 'dev' to 'edev.dev.parent' before registering extcon device -- switch_dev_unregister(sdev) - => extcon_dev_unregister(edev) - : no change but type change (sdev->edev) -- switch_get_state(sdev) - => extcon_get_state(edev) - : no change but type change (sdev->edev) and (return: int->u32) -- switch_set_state(sdev, state) - => extcon_set_state(edev, state) - : no change but type change (sdev->edev) and (state: int->u32) - -With this changes, the ex-switch extcon class device works as it once -worked as switch class device. However, it will now have additional -interfaces (both ABI and in-kernel API) and different ABI locations. -However, if CONFIG_ANDROID is enabled without CONFIG_ANDROID_SWITCH, -/sys/class/switch/* will be symbolically linked to /sys/class/extcon/ -so that they are still compatible with legacy userspace processes. - -****** STEP 2. Multistate (no more magic numbers in state value) - Extcon's extended features for switch device drivers with - complex features usually required magic numbers in state - value of switch_dev. With extcon, such magic numbers that - support multiple cables are no more required or supported. - - 1. Define cable names at edev->supported_cable. - 2. (Recommended) remove print_state callback. - 3. Use extcon_get_cable_state_(edev, index) or - extcon_get_cable_state(edev, cable_name) instead of - extcon_get_state(edev) if you intend to get a state of a specific - cable. Same for set_state. This way, you can remove the usage of - magic numbers in state value. - 4. Use extcon_update_state() if you are updating specific bits of - the state value. - -Example: a switch device driver w/ magic numbers for two cables. - "0x00": no cables connected. - "0x01": cable 1 connected - "0x02": cable 2 connected - "0x03": cable 1 and 2 connected - 1. edev->supported_cable = {"1", "2", NULL}; - 2. edev->print_state = NULL; - 3. extcon_get_cable_state_(edev, 0) shows cable 1's state. - extcon_get_cable_state(edev, "1") shows cable 1's state. - extcon_set_cable_state_(edev, 1) sets cable 2's state. - extcon_set_cable_state(edev, "2") sets cable 2's state - 4. extcon_update_state(edev, 0x01, 0) sets the least bit's 0. - -****** STEP 3. Notify other device drivers - - You can notify others of the cable attach/detach events with -notifier chains. - - At the side of other device drivers (the extcon device itself -does not need to get notified of its own events), there are two -methods to register notifier_block for cable events: -(a) for a specific cable or (b) for every cable. - - (a) extcon_register_interest(obj, extcon_name, cable_name, nb) - Example: want to get news of "MAX8997_MUIC"'s "USB" cable - - obj = kzalloc(sizeof(struct extcon_specific_cable_nb), - GFP_KERNEL); - nb->notifier_call = the_callback_to_handle_usb; - - extcon_register_intereset(obj, "MAX8997_MUIC", "USB", nb); - - (b) extcon_register_notifier(edev, nb) - Call nb for any changes in edev. - - Please note that in order to properly behave with method (a), -the extcon device driver should support multistate feature (STEP 2). - -****** STEP 4. Inter-cable relation (mutually exclusive) - - You can provide inter-cable mutually exclusiveness information -for an extcon device. When cables A and B are declared to be mutually -exclusive, the two cables cannot be in ATTACHED state simulteneously. - - -/***************************************************************** - * CHAPTER 2. * - * PORTING USERSPACE w/ SWITCH CLASS DEVICE SUPPORT * - *****************************************************************/ - -****** ABI Location - - If "CONFIG_ANDROID" is enabled, /sys/class/switch/* are created -as symbolic links to /sys/class/extcon/*. - - The two files of switch class, name and state, are provided with -extcon, too. When the multistate support (STEP 2 of CHAPTER 1.) is -not enabled or print_state callback is supplied, the output of -state ABI is same with switch class. |