[systemd-devel] [PATCH v3 2/4] udev: Update pointingstick rules to allow setting ibm trackpoint sensitivity

[Hans de Goede]

Hi,

On 07-04-15 12:23, David Herrmann wrote:
> Hi
>
> On Tue, Apr 7, 2015 at 12:09 PM, Hans de Goede <hdegoede at redhat.com> wrote:
>> IBM / Lenovo trackpoints allow specifying a sensitivity setting through a
>> ps/2 command, which changes the range of the deltas sent when using the
>> trackpoint. On some models with normal usage only deltas of 1 or 2 are send,
>> resulting in there only being 2 mouse cursor movement speeds, rather than
>> the expected fluid scale.
>>
>> Changing the sensitivity to a higher level than the bootup default fixes this,
>> the rule additions in this commit allows specifying a new sensitivity default
>> through hwdb giving a better ootb experience.
>> ---
>>   hwdb/70-pointingstick.hwdb   | 12 ++++++++++++
>>   rules/70-pointingstick.rules |  9 +++++++--
>>   2 files changed, 19 insertions(+), 2 deletions(-)
>>
>> diff --git a/hwdb/70-pointingstick.hwdb b/hwdb/70-pointingstick.hwdb
>> index a893da6..89f4b8a 100644
>> --- a/hwdb/70-pointingstick.hwdb
>> +++ b/hwdb/70-pointingstick.hwdb
>> @@ -42,6 +42,7 @@
>>   #
>>   # Allowed properties are:
>>   #   POINTINGSTICK_CONST_ACCEL
>> +#   POINTINGSTICK_SENSITIVITY
>>   #
>>   #########################################
>>   #      POINTINGSTICK_CONST_ACCEL        #
>> @@ -54,6 +55,17 @@
>>   # by how much to multiply deltas generated by the pointingstick to get
>>   # normalized deltas.
>>   #
>> +#########################################
>> +#      POINTINGSTICK_SENSITIVITY        #
>> +#########################################
>> +#
>> +# TPPS/2 IBM TrackPoint driver sensitivity sysfs setting
>> +#    POINTINGSTICK_SENSITIVITY=<sensitivity>
>> +#
>> +# Where <sensitivity> is a number between 0 and 255, note this property
>> +# only applies to TPPS/2 IBM TrackPoint devices, see
>> +# drivers/input/mouse/trackpoint.c in the Linux kernel sources.
>> +#
>>
>>   #
>>   # Sort by by brand, model
>> diff --git a/rules/70-pointingstick.rules b/rules/70-pointingstick.rules
>> index 5a853f3..15e34a0 100644
>> --- a/rules/70-pointingstick.rules
>> +++ b/rules/70-pointingstick.rules
>> @@ -6,11 +6,16 @@ ENV{ID_INPUT_POINTINGSTICK}=="", GOTO="pointingstick_end"
>>
>>   # skip later rules when we find something for this input device
>>   IMPORT{builtin}="hwdb --subsystem=input --lookup-prefix=pointingstick:", \
>> -  GOTO="pointingstick_end"
>> +  GOTO="pointingstick_apply_settings"
>>
>>   # device matching the input device name and the machine's DMI data
>>   KERNELS=="input*", \
>>     IMPORT{builtin}="hwdb 'pointingstick:name:$attr{device/name}:$attr{[dmi/id]modalias}'", \
>> -  GOTO="pointingstick_end"
>> +  GOTO="pointingstick_apply_settings"
>> +
>> +LABEL="pointingstick_apply_settings"
>> +
>> +TEST=="../../../sensitivity", ENV{POINTINGSTICK_SENSITIVITY}!="", \
>> +  ATTR{../../../sensitivity}="$env{POINTINGSTICK_SENSITIVITY}"
>
> You can read attributes of parents, but writing to them is not that
> easy. _Writing_ to ATTR always affects the event-device, not the
> matched parent.

Right, and that is what this rule does, it writes an ATTR using the path
from the event-device.

> The series looks reasonable, but I wonder why we cannot merge it into
> 60-keyboard.rule (60-evdev.rule now) like Peter's series does? In that
> case, please make this a builtin of input_id which uses
> udev_device_get_parent_subsystem_devtype() and look for the
> serio/atkbd (?) parent device, instead of hard-coding the path.

Why would we want to merge this into keyboard rules/hwdb? Trackpoints
always have a separate driver, input device and event node.

Regards,

Hans