I have no clue how you can look these things up in windows. Last time I used windows was 10 years ago. :-/

Have you tried it with one of the following boot parameters for the kernel in grub?

i8042.kbdreset=1 

or

i8042.nomux=1 i8042.reset

I tried themboth, without success... I also tried to compile and run the kernel 4.11, but it didn't fix it... I hope it will be fixed one day... I migth also try with kernel 4.12 but...

I don't know what to do honestly, or even if I should ship it back... 

It seems that the touchpad for the 15" version isn't recognized. Maybe the driver will come with the kernel 4.13. But there is no guarantee. You can ask maybe the people at elantech? I would ship it back. Maybe there are other manufactures that support linux better. I have a XPS 13" for work and this yoga 720 13", both work fine with linux. But I don't know about any 15" notebooks.

I got a Yoga 720 13", i5-7200u, 1080p display, 8 GB RAM, 256 GB SSD model from bestbuy. I can run Ubuntu 17.04, Mate desktop out of the box with almost everything working as expected. I first tried it in a LIVE USB session and then installed it to the SSD. I created a Win10/Ubuntu dual boot setup as follows.

(1) After booting into Windows for the first time, download and install all updates.. The pre-installed Lenovo service utility prompts to update the firmware.  I went ahead with it.

(2) It is necessary to change the storage setting in the BIOS from RAID to AHCI, in order for linux to recognize the internal SSD. As the pre-installed Win10 was installed in the RAID mode, chaning the mode as above will break Win10. In order to prevent this, before changing the mode, follow the steps outlined here to switch Win10 from RAID to AHCI without reinstallation.

http://triplescomputers.com/blog/uncategorized/solution-switch-windows-10-from-raidide-to-ahci-operation/

Alternatively, you might make a fresh installation of Win10 in the AHCI.

(3)  After switching Win10 to AHCI shrink the single windows partition using Disk Management utility to the desired capacity and make space for linux.

http://www.everydaylinuxuser.com/2015/11/how-to-shrink-windows-10-to-make-space.html

(4) Boot with Ubuntu Live-USB from USB 3.1 port. I installed Ubuntu in the UEFI mode.

(5) Using gparted, create desired partitions. I created 3 partitions. (root installation, /home and swap) and perform Ubuntu installation.

(6) The dual boot setup is now ready! Upon rebooting,  the UEFI boot menu shows options to boot into linux or windows. With Kernel 4.10 in Ubuntu 17.04, most of the things works out of the box as a laptop. (Wifi, sound, mic, suspend/resume, touch screen) I haven't yet fiddeled around to see if it correctly works in the tablet mode. 

(7) Update Ubuntu using the standard commands,

sudo apt update

sudo apt upgrade

I am yet to test this setup thoroughly, but the command,

acpi -b

estimates the battery life  >7 hours, in the idle mode.(medium screen brightness, wifi on, browsing in Google chrome/editing documents,no videos or cpu intensive tasks) Normally I keep the AC supply plugged in while working indoors.

(8) It seems that the battery is discharging faster than expected in the suspend mode. 2% discharge after 10 hours of suspend. I am investigating this.

I hope these instructions help someone to setup dual boot in this laptop!

I ended up returning it, since the Lenovo rep said it was the one shown on the USB bus

For xinput --list, it didn't show up there at all, which I'm chalking up to it not being recognized by any of the kernel drivers. I attempted to echo the other ID into /sys/module/usbhid/drivers/usb:usbhid/new_id, which can often enable support for newer devices whose IDs might not have made it into the kernel modules yet. I2c_hid doesn't seem to have the same device node at least on the system I'm on now, so it might be just a matter of finding a patch in 4.10.13-1-ARCH that introduces support. I've got a BZ open about it at https://bugzilla.redhat.com/show_bug.cgi?id=1446365 but since I lack the device now, it'd be difficult to continue to troubleshoot.

Best of luck to all fellow Linux users, it's such excellent hardware it was a shame to have to return it

I've been researching a lot, and I think I have something that might work. I don't have the laptop yet. I'm hoping someone can try this.

Windows reports this as an Elantech device with the following ids

HID\VEN_ELAN&DEV_0651&Col01
HID\ELAN0651&Col01
HID*ELAN0651&Col01

If it is a i12c device there is a driver for that.

http://elixir.free-electrons.com/linux/latest/source/drivers/input/mouse/elan_i2c_core.c

You can see at the bottom the MODULE_DEVICE_TABLE variables. This is what is used to match a device with a driver.

There is a variable that looks like this:

static const struct acpi_device_id elan_acpi_id[] = {
	{ "ELAN0000", 0 },
	{ "ELAN0100", 0 },
	{ "ELAN0600", 0 },
	{ "ELAN0605", 0 },
	{ "ELAN1000", 0 },
	{ }
};

Those numbers are really similar to 0651. I'm wondering if

    { "ELAN0651", 0 },

(Which is exactly what shows up in the Windows devices ID) was added to that list, would the elan_i12c driver load and work for this device. I really hope someone can try this and report if it works.

I have ordered this model as well as it seems it has good Linux support. A new firmware has been released but unfortunately its Windows install only

https://download.lenovo.com/consumer/mobiles/4mcn20ww.exe

and no option of USB/ISO.

Will alternate BIOS update options be added at a later point in time? I am not willing to setup / retain Windows just to update the BIOS!!!

Hello,

i also bought the 15" Lenovo Yoga 720 so i try it with building the elan_i2c driver with the sugessted changes ( add the id to the list in the .c file ) but nothing happens. What i did:

Change the source in the file.

Compile ther kernel

Install Kernel and restart.

Check the used kerlen with uname -r ( its my cusotm kernel )

Check with lsmod if elan_i2c is loaded ( yes but nothing use it )

That was my best guess. Mines coming in Monday. Maybe if we can dump the i12c data on windows we would see something.

I did this firmware udpate before install linux, i cant find any options for the trackpad. Its so saidly that 13" model works and 15" model doenst. It would be great if lenovo would tell us whats the differents of the devices.