Re: [BUG] i2c-hid: ELAN Touchpad does not work on ASUS X580GD

[Jarkko Nikula]

Hi

On 05/07/2018 11:07 AM, Chris Chiu wrote:

> > Besides, according to ASUS's input, they observed that after entering
> > the OS, the frequency of SCL is too fast (about 600kHz) and the SCL High
> > time is around 450ns, not following I2C spec which is 0.6us.
> > https://pasteboard.co/HjzSWXd.png
> Some update, we can make the touchpad work by simply modifying the
> clk_rate of spt_i2c_info from 120000000 to 133000000 in intel-lpss-pci.c for
> specific PCI ID 8086:a368 ~ a36a (CoffeeLake). Is the clock setting different
> for the CoffeeLake series?
Hmm.. at quick look it looks like to be 133 MHz but I want to double 
check first from other specs. I'm also wondering why it results 600 kHz 
instead of expected 133/120 * 400 kHz = 443 kHz. Need to check timing 
parameters too.

--
Jarkko