On Mar 10 2017 or thereabouts, 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 can see this guards for MOUSE_PS2_SYNAPTICS_SMBUS, but not for MOUSE_PS2_SMBUS. So unless I am completely missing the point, if users disable SYNAPTICS_SMBUS but keep PS2_SMBUS there might be a problem. > > I am perfectly fine to tie psmouse to I2C *core*, we do not need to have > adapters loaded for it to work (hopefully). K. > > > > > > 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. Oh, I see. I haven't thought at the userspace issue. > > 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. Oh, yes, I do remember this. However, I think the device was i2c_hid, not SMBus. You can check if that's the case by looking at the DSDT, if it has a HID over I2C touchpad, then that the same issue. > > When your SMBus connection is dead do you see anything on the bus? At > that address? Or it is completely unresponsive? Completely unresponsive, nothing on the bus (as if there was nothing physically wired). I managed to discover that using psmouse as a module, not in bzImage allows to have the bus properly set. So I guess there is some timing issue (and that's going to be a pain to figure out). In addition to the pdata fix I just sent in reply to 6/8, I have one extra fix for rmi30 in case the pdata gets corrupted (or if f30 has been deliberately disabled). Cheers, Benjamin > > Thanks. > > -- > Dmitry -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
