Re: [PATCH v4 00/17] *** Implement simple haptic HID support ***

[Sean O'Brien <seobrien@chromium.org>]

On Fri, Oct 7, 2022 at 8:30 PM Angela Czubak <acz@semihalf.com> wrote:
> 
> This patch series introduces changes necessary to support devices
> using simple haptic HID pages.
> Implementation attempts to follow the discussion below:
> https://www.spinics.net/lists/linux-input/msg61091.html
> 
> Introduce new haptic defines as specified in HID Usage Tables.
> 
> Add new force feedback effect type in order to facilitate using
> simple haptic force feedback.
> 
> Add INPUT_PROP_HAPTIC_TOUCHPAD to mark touchpad exposing simple haptic
> support.
> 
> Add new struct hid_haptic_device so as to gather simple haptic related
> configuration and current state of the device.
> 
> Add new functions to be triggered during HID input mapping and
> configuration in order to detect simple haptic devices.
> 
> Modify HID input so that haptic output reports are parsed.
> 
> Initialize a haptic device.
> 
> Modify FF core so that effect IDs can be shared between multiple open file
> handles.
> 
> Add shared release and press effects for a simple haptic device.
> 
> Calculate pressure resolution if units are grams or newtons.
> 
> Add support for kernel-driven mode of simple haptic device.
> 
> Toggle ABS_PRESSURE generation by input-mt on request.
> 
> Implement functions allowing switching between kernel-managed mode
> and autonomous mode.
> 
> Add simple haptic support for hid-multitouch driver.
> 
> Implement EVIOCFF(TAKE|RELEASE)CONTROL ioctls so that userspace can take
> and release control of shared release and press effects.
> 
> v2:
> - Describe INPUT_PROP_HAPTIC_TOUCHPAD in
>   Documentation/input/event-codes.rst
> - Do not extract mt_get_feature(), use hid_hw_wait() instead
> - Define HID_UNIT_GRAM and HID_UNIT_NEWTON
> - Calculate pressure sum in input-mt if INPUT_MT_TOTAL_FORCE flags set
> - Use u* instead of __u* in struct hid_haptic_device
> - Solve problems with report IDS >= 0xF as Dmitry suggests
> 
> v3:
> - Get rid of INPUT_PROP_HAPTIC_TOUCHPAD property as haptic device does not
>   gave to be a touchpad
> - Introduce notion of haptic forcepads; generate haptic feedback in kernel
>   mode only for forcepads
> - Generate clicks based on maximum pressure across slots instead of the sum
> - Fix off-by-one bug in hid_haptic_upload_effect()
> - Fix resume/suspend: issue hid_haptic_resume() in mt_resume() and
>   hid_haptic_suspend() in mt_suspend()
> - Add reset callback for HID i2c devices
> - Implement reset callback for HID multitouch haptic devices
> - Implement lid handler triggering touchpad recalibration for Redrix
> 
> v4:
> - Fix mt_reset callback to end earlier if no input devices have been
>   configured yet to avoid iterating over uninitialized hid->inputs list
> 
> Angela Czubak (17):
>   HID: add haptics page defines
>   Input: add FF_HID effect type
>   HID: haptic: introduce hid_haptic_device
>   HID: input: allow mapping of haptic output
>   HID: haptic: initialize haptic device
>   Input: add shared effects
>   HID: haptic: implement release and press effects
>   HID: input: calculate resolution for pressure
>   HID: haptic: add functions handling events
>   Input: MT - add INPUT_MT_MAX_FORCE flags
>   HID: haptic: add hid_haptic_switch_mode
>   HID: multitouch: add haptic multitouch support
>   Input: introduce EVIOCFF(TAKE|RELEASE)CONTROL
>   HID: haptic: add hid_haptic_change_control
>   HID: add HID device reset callback
>   HID: haptic: implement HID haptic reset callback
>   HID: multitouch: Add lid handler for touchpad on Redrix chromebook
> 
>  drivers/hid/Kconfig                |  14 +
>  drivers/hid/Makefile               |   1 +
>  drivers/hid/hid-haptic.c           | 753 +++++++++++++++++++++++++++++
>  drivers/hid/hid-haptic.h           | 152 ++++++
>  drivers/hid/hid-input.c            |  18 +-
>  drivers/hid/hid-multitouch.c       | 313 +++++++++++-
>  drivers/hid/i2c-hid/i2c-hid-core.c |  21 +
>  drivers/input/evdev.c              |   6 +
>  drivers/input/ff-core.c            | 129 ++++-
>  drivers/input/input-mt.c           |  16 +-
>  include/linux/hid.h                |  31 ++
>  include/linux/input.h              |   5 +
>  include/linux/input/mt.h           |   1 +
>  include/uapi/linux/input.h         |  26 +-
>  14 files changed, 1469 insertions(+), 17 deletions(-)
>  create mode 100644 drivers/hid/hid-haptic.c
>  create mode 100644 drivers/hid/hid-haptic.h

Hello Jiri,

Will you be able to review this series?

Best,
Sean