Date:   Fri, 10 Mar 2017 12:12:40 -0800
From:   Dmitry Torokhov <dmitry.torokhov@...il.com>
To:     Andrew Duggan <aduggan@...aptics.com>
Cc:     Benjamin Tissoires <benjamin.tissoires@...hat.com>,
        linux-kernel@...r.kernel.org, linux-input@...r.kernel.org
Subject: Re: [PATCH 0/8] PS

On Fri, Mar 10, 2017 at 10:56:33AM -0800, Andrew Duggan wrote:
> On 03/10/2017 09:52 AM, Dmitry Torokhov wrote:
> >On Fri, Mar 10, 2017 at 04:57:35PM +0100, Benjamin Tissoires wrote:
> >>Hi Dmitry,
> >>
> >>On Mar 09 2017 or thereabouts, Dmitry Torokhov wrote:
> >>>Hi,
> >>>
> >>>This is refresh of Benjamin's patches trying to bridge PS/2 and SMbus
> >>>devices for better support of Synaptics RMI4 touchpads (and Elans later).
> >>Thanks!
> >>
> >>I have some issues/comments and am still working on those. Here are some
> >>general comments:
> >>
> >>>The main difference is that we do not have platform device, as it only
> >>>adds another indirection level, and have psmouse create SMBus companion
> >>The purpose of having the platform device was to not have dependency
> >>between psmouse and I2C. Right now I think that patch 6/8 will fail to
> >>compile if I2C=m and PSMOUSE=y (I may be wrong).
> >This is taken care by the following guards in users if MOUSE_PS2_SMBUS:
> >
> >depends on I2C=y || I2C=MOUSE_PS2
> >
> >I am perfectly fine to tie psmouse to I2C *core*, we do not need to have
> >adapters loaded for it to work (hopefully).
> >
> >>>directly. Because serio ports complete registration asynchronously, we do
> >>>not deadlock on psmouse_mutex when even if we have a pass-through port.
> >>>(Frankly we need to revisit this whole serio and psmouse thing, use of
> >>>global serio_mutex and psmouse_mutex is hurting us; they were needed when
> >>>driver core could not recursively iterate over device and driver lists).
> >>Agree, this is a giant PITA.
> >>
> >>>We also do not allow overriding serio driver, instead we teach psmouse
> >>>about "special" devices and let it continue own the serio port and make
> >>>sure nobody else touches it.
> >>>
> >>>To work around issue with psmouse_reconnect() running sometimes too late,
> >>>we add "fast reconnect" option to serio. Not too pretty, but gets the job
> >>>done. We may need to revisit whole serio PM story later and stop "cheating"
> >>>and pretending that device is resumed when it is not, but for that we need
> >>>to teach PM core about devices that are OK not to wait for before resuming
> >>>userspace. Anyway, much bigger topic for later.
> >>I thought there was already the ability to say that a driver needs to be
> >>run in a different thread for PM functions (IIRC i2c-hid uses
> >>device_enable_async_suspend(&client->dev); and this "should" do the
> >>trick).
> >The issue is that currently asynchronous resume still has to complete
> >before we start resuming userspace, as PS/2 is way too slow. So the
> >current solution marks device as resumed right away, and mouse may
> >become responsive 2 seconds later, but that is good as we do not idly
> >sit and wait but have userspace start turning on the screen and do other
> >useful stuff. Maybe user can already start typing their password into
> >screen locker.
> >
> >We would need to give a way to drivers to indicate to PM core just how
> >asynchronous our resume can be.
> >
> >>>This seems to be working on X1 Carbon and also not breaking my HP 1040 with
> >>>forcepad (unfortunately it seems to be using some other SMBus controller
> >>>for connecting Synaptics, as I see nothing at 0x2c when loading i2c-i801).
> >>Well, on my T450, the SMBus connection is dead too. I can't seem to talk
> >>to the device at all. This happens when the firmware believes it needs
> >>to stay on PS/2 and gets completely deaf to I2C. I solved this by
> >>calling psmouse_deactivate(), but this time, it looks like some other
> >>function needs to be called.
> >>
> >>I'll keep investigating and report back.
> >I've heard a rumors that HP 1020 uses a Microtech SMbus controller for
> >its touchpad, it could be that 1040 is similar.
> >
> >When your SMBus connection is dead do you see anything on the bus? At
> >that address? Or it is completely unresponsive?
> 
> Try the I2C address 0x20 for the HP forcepad. I have gotten previous
> versions of Benjamin's SMBus patches working on a similar system. It
> is a HP Elitebook Folio 940 and the forcepad was at address 0x20 and
> it was on the i801 bus. The HP 1020 does have a microchip I2C
> controller, but thats connected to a HID / I2C touchpad. The 1020
> was a one off so the 1040 should be the more common SMBus
> implementation.
> 
> I also have not been able to get this patch series to successfully
> switch over to SMBus mode. But, I have not had a chance to do
> anything besides apply the patches and build. This is the output
> from a Lenovo W541:
> 
> [    9.674826] psmouse serio1: synaptics: queried max coordinates: x
> [..5676], y [..4758]
> [    9.705273] psmouse serio1: synaptics: queried min coordinates: x
> [1266..], y [1096..]
> [    9.705276] psmouse serio1: synaptics: Trying to set up SMBus access
> [    9.707946] psmouse serio1: synaptics: SMbus companion is not ready yet
> [    9.764848] psmouse serio1: synaptics: Touchpad model: 1, fw:
> 8.1, id: 0x1e2b1, caps: 0xf003a3/0x943300/0x12e800/0x10000, board
> id: 3053, fw id: 2560
> [    9.764853] psmouse serio1: synaptics: serio: Synaptics
> pass-through port at isa0060/serio1/input0
> [   10.418268] psmouse serio2: trackpoint: IBM TrackPoint firmware:
> 0x0e, buttons: 3/3
> ...
> [   27.112954] psmouse serio1: synaptics: queried max coordinates: x
> [..5676], y [..4758]
> [   27.142555] psmouse serio1: synaptics: queried min coordinates: x
> [1266..], y [1096..]
> [   27.142559] psmouse serio1: synaptics: Trying to set up SMBus access
> [   27.169776] psmouse serio1: synaptics: SMbus companion is not ready yet
> [   27.226071] psmouse serio1: synaptics: Touchpad model: 1, fw:
> 8.1, id: 0x1e2b1, caps: 0xf003a3/0x943300/0x12e800/0x10000, board
> id: 3053, fw id: 2560
> [   27.226087] psmouse serio1: synaptics: serio: Synaptics
> pass-through port at isa0060/serio1/input0
> [   27.880282] psmouse serio3: trackpoint: IBM TrackPoint firmware:
> 0x0e, buttons: 3/3

Yay, that works:

[  980.124573] psmouse serio3: synaptics: queried max coordinates: x [..5676], y [..4690]
[  980.155902] psmouse serio3: synaptics: queried min coordinates: x [1266..], y [1162..]
[  980.155915] psmouse serio3: synaptics: Trying to set up SMBus access
[  980.229405] rmi4_f01 rmi4-00.fn01: found RMI device, manufacturer: Synaptics, product: TM2685-009, fw id: 1608298
[  980.293225] input: Synaptics TM2685-009 as /devices/rmi4-00/input/input42
[  980.305824] rmi4_smbus 9-0020: registered rmi smb driver at 0x20.

Thanks Andrew!

-- 
Dmitry

Powered by blists - more mailing lists