Re: [PATCH 0/8] PS

[Andrew Duggan <aduggan@synaptics.com>]

On 03/10/2017 12:12 PM, Dmitry Torokhov wrote:
> 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!
>
Cool! FYI, forcepads don't have a F30 so currently there is nothing to 
report BTN_LEFT or BUTTONPAD which will probably confuse userspace about 
what type of device it is. I have a patch which I worked on a year ago 
for F21 which is the force function for these devices. It will report a 
click when the firmware determines that a certain amount of force has 
been applied. I can take a look at that patch again and submit it when I 
get a chance now that we are closer to getting these device working in 
RMI mode.

Andrew