Re: [PATCH v2 0/7] New Lenovos 2015 touchpads: party time!

From: Hans de Goede
Date: Tue Mar 10 2015 - 03:23:39 EST


On 10-03-15 07:17, Steven Noonan wrote:
Hi Benjamin,

I just got a ThinkPad X250 in today and have tried out your patches on
3.19.1. Before the patches, the top TrackPoint buttons weren't working
at all, but the clickpad was working fine. For the most part, your
patches fixed the TrackPoint.

There's something weird going on though. If I control the mouse cursor
with the trackpoint nub, it feels "slow". At first I though it was
running the video mode at half the normal refresh rate, because the
pointer was only moving at what felt like a 30Hz refresh rate. But
then I tried the trackpad, and it behaves as expected (snappy and
responsive). Note that this is a definite difference between the BDW
generation and the HSW generation, as my HSW ThinkPad Yoga feels fine.

Is there something in the driver that controls the TrackPoint nub's
sampling rate?

Actually the trackpoint sensitivity is of (less sensitive) on the t440 /
x240 generation too. There it seems slower then with previous thinkpads
as well. I was hoping this would be fixed with the t450, but given that
they've recycled the keyboard it makes sense that it is not fixed.

I still have writing a kernel patch for this on my todo list. In the
mean time you can change the sensitivity as documented here:

I plan to write a kernel patch to set a different sensitivity by default
on these newer models to fix this ootb. If you can let me know what seems
to be a good sensitivity that would be useful.



- Steven

On Mon, Mar 9, 2015 at 12:36 PM, Benjamin Tissoires
<benjamin.tissoires@xxxxxxxxx> wrote:
On Mon, Mar 9, 2015 at 4:24 AM, Hans de Goede <hdegoede@xxxxxxxxxx> wrote:

On 09-03-15 07:46, Dmitry Torokhov wrote:

On Wed, Feb 25, 2015 at 03:58:20PM +0100, Hans de Goede wrote:


On 25-02-15 15:36, Benjamin Tissoires wrote:

On Mon, Feb 16, 2015 at 10:23 PM, Benjamin Tissoires
<benjamin.tissoires@xxxxxxxxx> wrote:

On Fri, Feb 6, 2015 at 3:04 PM, Benjamin Tissoires
<benjamin.tissoires@xxxxxxxxxx> wrote:


This is the second episode of the Lenovo 2015 party :)

Thanks to Andrew, we now have an idea within the driver of what are
the extra
buttons aimed for, and the patch series looks cleaner.
Many thanks for your help.

I marked only patches 1/7, 2/7 and 3/7 as stable because they are
stable fixes. Without the rest of the series, user-space can cope with
kernel result, and so there is IMO no need to backport too many
patches in
stable. I bet distributions will cherry-pick the rest of the series


any chances we consider this for 3.20 (or whatever it will be
I'd really like to see this accepted upstream in one way or one other
so we will prevent the mess we had to deal with last year.

Hans, Dmitry,

well, it's been 3 weeks since I received the loaner I have to support
these touchpads. I will have to return it next week or the week after
at most. That means that I will not be able to conduct more tests at
that point.
Can I ask you to please review the series?

Ah, sorry I missed you did a v2 (I did review v1).

Series looks good to me and is:

Acked-by: Hans de Goede <hdegoede@xxxxxxxxxx>

I did a few edits of the patches in the 2 series so I created a separate
branch "synaptics" based on 3.19. I'd appreciate if you could give it q
quick spin before I will send it for 4.0.

I don't have access to the hardware in question, but Benjamin does, so
we'll have to wait (a bit) for him to wake up :)

It took me a little bit of time to retrieve the laptop and get it tested.
So far, so good:
- t440s (2013) shows the correct behavior
- x1 carbon 3 has the buttons properly forwarded through the
trackstick interface and are reacting as expected.

Thanks Dmitry!

I've added Daniel to the thread and asked it this morning if he could
also give a try to the series.

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